@article {pmid31621248,
year = {2019},
author = {Feng, H and Meng, PP and Dou, Q and Zhang, SX and Wang, HH and Wang, CY},
title = {[Advances in mechanisms of nutrient exchange between mycorrhizal fungi and host plants].},
journal = {Ying yong sheng tai xue bao = The journal of applied ecology},
volume = {30},
number = {10},
pages = {3596-3604},
doi = {10.13287/j.1001-9332.201910.034},
pmid = {31621248},
issn = {1001-9332},
abstract = {Mycorrhizae, formed through the colonization of soil mycorrhizal fungi into the roots of host plants, are common symbiosis in the terrestrial ecosystems. The establishment of mycorrhizae is mainly based on the bidirectional nutrient exchanges between the symbiotic partners. Mycorrhizal fungi can absorb mineral nutrients, such as nitrogen and phosphorus, from soil and transport them to the host plants for their growth. As an exchange, host plants supply mycorrhizal fungi with the carbohydrates in the form of lipids or sugars, which are essential for fungal growth. In recent years, the mechanism of nutrient exchange between the mycorrhizal fungi and host plants has been a hot research topic. Important progresses have been achieved in mechanisms of host plants nutrient uptake and transport mediated by the mycorrhizal fungi. In this review, recent advances in nutrient exchange between arbuscular mycorrhizal fungi, ectomycorrhizal fungi and host plants were summarized, especially in the absorption and bidirectional transfer mechanisms of important nutrients, such as carbon, nitrogen and phosphorus. The potential regulatory effects of nutrient exchange in the mycorrhizal development were also reviewed. In addition, key problems and prospects of related researches were analyzed. This paper would be meaningful for the establishment of mycorrhizal model and the optimization of mycorrhizal effects.},
}
@article {pmid31621153,
year = {2019},
author = {Hill, PW and Broughton, R and Bougoure, J and Havelange, W and Newsham, KK and Grant, H and Murphy, DV and Clode, P and Ramayah, S and Marsden, KA and Quilliam, RS and Roberts, P and Brown, C and Read, DJ and Deluca, TH and Bardgett, RD and Hopkins, DW and Jones, DL},
title = {Angiosperm symbioses with non-mycorrhizal fungal partners enhance N acquisition from ancient organic matter in a warming maritime Antarctic.},
journal = {Ecology letters},
volume = {},
number = {},
pages = {},
doi = {10.1111/ele.13399},
pmid = {31621153},
issn = {1461-0248},
support = {//British Antarctic Survey/ ; //University of Western Australia/ ; NE/I012303/1//Natural Environment Research Council/ ; },
abstract = {In contrast to the situation in plants inhabiting most of the world's ecosystems, mycorrhizal fungi are usually absent from roots of the only two native vascular plant species of maritime Antarctica, Deschampsia antarctica and Colobanthus quitensis. Instead, a range of ascomycete fungi, termed dark septate endophytes (DSEs), frequently colonise the roots of these plant species. We demonstrate that colonisation of Antarctic vascular plants by DSEs facilitates not only the acquisition of organic nitrogen as early protein breakdown products, but also as non-proteinaceous d-amino acids and their short peptides, accumulated in slowly-decomposing organic matter, such as moss peat. Our findings suggest that, in a warming maritime Antarctic, this symbiosis has a key role in accelerating the replacement of formerly dominant moss communities by vascular plants, and in increasing the rate at which ancient carbon stores laid down as moss peat over centuries or millennia are returned to the atmosphere as CO2 .},
}
@article {pmid31619728,
year = {2019},
author = {Nguyen, TD and Cavagnaro, TR and Watts-Williams, SJ},
title = {The effects of soil phosphorus and zinc availability on plant responses to mycorrhizal fungi: a physiological and molecular assessment.},
journal = {Scientific reports},
volume = {9},
number = {1},
pages = {14880},
doi = {10.1038/s41598-019-51369-5},
pmid = {31619728},
issn = {2045-2322},
abstract = {The positive effects of arbuscular mycorrhizal fungi (AMF) have been demonstrated for plant biomass, and zinc (Zn) and phosphorus (P) uptake, under soil nutrient deficiency. Additionally, a number of Zn and P transporter genes are affected by mycorrhizal colonisation or implicated in the mycorrhizal pathway of uptake. However, a comprehensive study of plant physiology and gene expression simultaneously, remains to be undertaken. Medicago truncatula was grown at different soil P and Zn availabilities, with or without inoculation of Rhizophagus irregularis. Measures of biomass, shoot elemental concentrations, mycorrhizal colonisation, and expression of Zn transporter (ZIP) and phosphate transporter (PT) genes in the roots, were taken. Mycorrhizal plants had a greater tolerance of both P and Zn soil deficiency; there was also evidence of AMF protecting plants against excessive Zn accumulation at high soil Zn. The expression of all PT genes was interactive with both P availability and mycorrhizal colonisation. MtZIP5 expression was induced both by AMF and soil Zn deficiency, while MtZIP2 was down-regulated in mycorrhizal plants, and up-regulated with increasing soil Zn concentration. These findings provide the first comprehensive physiological and molecular picture of plant-mycorrhizal fungal symbiosis with regard to soil P and Zn availability. Mycorrhizal fungi conferred tolerance to soil Zn and P deficiency and this could be linked to the induction of the ZIP transporter gene MtZIP5, and the PT gene MtPT4.},
}
@article {pmid31530279,
year = {2019},
author = {Daza, FFF and Roman, GR and Rodriguez, MV and Vargas, IAG and Heano, HC and Cereda, MP and Mulet, RAC},
title = {Spores of Beauveria bassiana and Trichoderma lignorum as a bioinsecticide for the control of Atta cephalotes.},
journal = {Biological research},
volume = {52},
number = {1},
pages = {51},
doi = {10.1186/s40659-019-0259-y},
pmid = {31530279},
issn = {0717-6287},
support = {025-2016//Colciencias/ ; },
mesh = {Animals ; Ants/*microbiology ; Beauveria/growth & development/*pathogenicity ; *Biological Control Agents ; Colombia ; Pest Control, Biological/*methods ; Spores, Fungal ; Symbiosis ; Trichoderma/growth & development/*pathogenicity ; Universities ; },
abstract = {BACKGROUND: The leafcutter ant (Atta cephalotes) is associated with losses in the agricultural sector, due to its defoliating activity; for its control, biological, mechanical and chemical methods have been developed, the latter associated with adverse effects on human and environmental health. This research validated in the field for the control of the leafcutter ant (A. cephalotes) using a mixture of Beauveria bassiana and Trichoderma lignorum spores.<br><br>METHODS: The effectiveness from the combination of spores of B. bassiana and T. lignorum with an initial concentration of 2 × 109 spores/ml, in the following proportions of B. bassiana and T. lignorum, A (1:1), of each fungus. It was evaluated within the university campus, comparing it with two commercial formulations, Mycotrol (B. bassiana) and Mycobac (T. lignorum). Additionally, this formulation was evaluated in 49 nests distributed 16 in 14 locations in Colombia. The formulation application was carried out by direct application, using a pump at a speed of 10 ml/m2. The effectiveness was estimated from the reduction of the flow of ants, evaluating the statistically significant differences using the ANOVA and Tukey-test.<br><br>RESULTS: Effective control of 90% of the nests was observed in the field phase in 60 days, except in nests with areas > 50 m2 that were located in regions with high rainfall (annual average precipitation above 7000 mm), such as Buenaventura.<br><br>CONCLUSIONS: In this work, it was demonstrated that the combination of B. bassiana and T. lignorum spores represent a viable alternative for the control of the leafcutter ant, in which the effectiveness is related to several factors, including the size of the nest and the rainfall in the area.},
}
@article {pmid31370098,
year = {2019},
author = {Riley, RC and Cavagnaro, TR and Brien, C and Smith, FA and Smith, SE and Berger, B and Garnett, T and Stonor, R and Schilling, RK and Chen, ZH and Powell, JR},
title = {Resource allocation to growth or luxury consumption drives mycorrhizal responses.},
journal = {Ecology letters},
volume = {22},
number = {11},
pages = {1757-1766},
doi = {10.1111/ele.13353},
pmid = {31370098},
issn = {1461-0248},
support = {DP140103936//Australian Research Council/ ; },
mesh = {*Mycorrhizae ; Nitrogen ; Phosphorus ; Resource Allocation ; Symbiosis ; },
abstract = {Highly variable phenotypic responses in mycorrhizal plants challenge our functional understanding of plant-fungal mutualisms. Using non-invasive high-throughput phenotyping, we observed that arbuscular mycorrhizal (AM) fungi relieved phosphorus (P) limitation and enhanced growth of Brachypodium distachyon under P-limited conditions, while photosynthetic limitation under low nitrogen (N) was exacerbated by the fungus. However, these responses were strongly dependent on host genotype: only the faster growing genotype (Bd3-1) utilised P transferred from the fungus to achieve improved growth under P-limited conditions. Under low N, the slower growing genotype (Bd21) had a carbon and N surplus that was linked to a less negative growth response compared with the faster growing genotype. These responses were linked to the regulation of N : P stoichiometry, couples resource allocation to growth or luxury consumption in diverse plant lineages. Our results attest strongly to a mechanism in plants by which plant genotype-specific resource economics drive phenotypic outcomes during AM symbioses.},
}
@article {pmid30532066,
year = {2018},
author = {Vďačný, P and Érseková, E and Šoltys, K and Budiš, J and Pecina, L and Rurik, I},
title = {Co-existence of multiple bacterivorous clevelandellid ciliate species in hindgut of wood-feeding cockroaches in light of their prokaryotic consortium.},
journal = {Scientific reports},
volume = {8},
number = {1},
pages = {17749},
doi = {10.1038/s41598-018-36245-y},
pmid = {30532066},
issn = {2045-2322},
mesh = {Animals ; Bacteria/*classification/genetics ; Bacteroidetes/physiology ; Biodiversity ; Cockroaches/*microbiology ; Digestive System/*microbiology ; Euryarchaeota/physiology ; Firmicutes/physiology ; Prokaryotic Cells/microbiology ; Proteobacteria/physiology ; Symbiosis/physiology ; Wood ; },
abstract = {The hindgut of wood-feeding Panesthia cockroaches harbours a diverse microbial community, whose most morphologically prominent members are bacterivorous clevelandellid ciliates. Co-occurrence and correlation patterns of prokaryotes associated with these endosymbiotic ciliates were investigated. Multidimensional scaling based on taxa interaction-adjusted index showed a very clear separation of the hindgut ciliate samples from the ciliate-free hindgut samples. This division was corroborated also by SparCC analysis which revealed strong negative associations between prokaryotic taxa that were relatively more abundant in the ciliate-free hindgut samples and prokaryotic taxa that were more abundant in the ciliate samples. This very likely reflects the grazing behaviour of hindgut ciliates which prefer Proteobacteria, Firmicutes and Actinobacteria, causing their abundances to be increased in the ciliate samples at the expense of abundances of Euryarchaeota and Bacteroidetes which prevail in the hindgut content. Ciliate species do not distinctly differ in the associated prokaryotes, indicating that minute variations in the proportion of associated bacteria might be sufficient to avoid competition between bacterivorous ciliate species and hence enable their co-occurrence in the same host. The nearest free-living relatives of hindgut ciliates have a different pattern of associations with prokaryotes, i.e., alphaproteobacteria are predominantly associated with free-living ciliates while gammaproteobacteria with hindgut ciliates.},
}
@article {pmid29701804,
year = {2018},
author = {Calvo-Begueria, L and Rubio, MC and Martínez, JI and Pérez-Rontomé, C and Delgado, MJ and Bedmar, EJ and Becana, M},
title = {Redefining nitric oxide production in legume nodules through complementary insights from electron paramagnetic resonance spectroscopy and specific fluorescent probes.},
journal = {Journal of experimental botany},
volume = {69},
number = {15},
pages = {3703-3714},
pmid = {29701804},
issn = {1460-2431},
mesh = {Electron Spin Resonance Spectroscopy ; Fabaceae/*metabolism ; Fluorescent Dyes ; Leghemoglobin/*metabolism ; Nitric Oxide/*metabolism ; *Nitrogen Fixation ; Root Nodules, Plant/metabolism ; Symbiosis ; },
abstract = {Nitric oxide (NO) is a signaling molecule with multiple functions in plants. Given its critical importance and reactivity as a gaseous free radical, we have examined NO production in legume nodules using electron paramagnetic resonance (EPR) spectroscopy and the specific fluorescent dye 4,5-diaminofluorescein diacetate. Also, in this context, we critically assess previous and current views of NO production and detection in nodules. EPR of intact nodules revealed that nitrosyl-leghemoglobin (Lb2+NO) was absent from bean or soybean nodules regardless of nitrate supply, but accumulated in soybean nodules treated with nitrate that were defective in nitrite or nitric oxide reductases or that were exposed to ambient temperature. Consequently, bacteroids are a major source of NO, denitrification enzymes are required for NO homeostasis, and Lb2+NO is not responsible for the inhibition of nitrogen fixation by nitrate. Further, we noted that Lb2+NO is artifactually generated in nodule extracts or in intact nodules not analyzed immediately after detachment. The fluorescent probe detected NO formation in bean and soybean nodule infected cells and in soybean nodule parenchyma. The NO signal was slightly decreased by inhibitors of nitrate reductase but not by those of nitric oxide synthase, which could indicate a minor contribution of plant nitrate reductase and supports the existence of nitrate- and arginine-independent pathways for NO production. Together, our data indicate that EPR and fluorometric methods are complementary to draw reliable conclusions about NO production in plants.},
}
@article {pmid29700820,
year = {2018},
author = {Kremer, JMM and Nooten, SS and Cook, JM and Ryalls, JMW and Barton, CVM and Johnson, SN},
title = {Elevated atmospheric carbon dioxide concentrations promote ant tending of aphids.},
journal = {The Journal of animal ecology},
volume = {87},
number = {5},
pages = {1475-1483},
doi = {10.1111/1365-2656.12842},
pmid = {29700820},
issn = {1365-2656},
mesh = {Animals ; *Ants ; *Aphids ; Carbon Dioxide ; Plants ; Symbiosis ; },
abstract = {Animal mutualisms, which involve beneficial interactions between individuals of different species, are common in nature. Insect-insect mutualism, for example, is widely regarded as a keystone ecological interaction. Some mutualisms are anticipated to be modified by climate change, but the focus has largely been on plant-microbe and plant-animal mutualisms rather than those between animals. Ant-aphid mutualisms, whereby ants tend aphids to harvest their honeydew excretions and, in return, provide protection for the aphids, are widespread. The mutualism is heavily influenced by the quality and quantity of honeydew produced by aphids, which is directly affected by host plant quality. As predicted increases in concentrations of atmospheric carbon dioxide (eCO2) are widely reported to affect plant nutritional chemistry, this may also alter honeydew quality and hence the nature of ant-aphid mutualisms. Using glasshouse chambers and field-based open-top chambers, we determined the effect of eCO2 on the growth and nutritional quality (foliar amino acids) of lucerne (Medicago sativa). We determined how cowpea aphid (Aphis craccivora) populations and honeydew production were impacted when feeding on such plants and how this affected the tending behaviour of ants (Iridomyrmex sp.). eCO2 stimulated plant growth but decreased concentrations of foliar amino acids by 29% and 14% on aphid-infested plants and aphid-free plants, respectively. Despite the deterioration in host plant quality under eCO2 , aphids maintained performance and populations were unchanged by eCO2 . Aphids induced higher concentrations of amino acids (glutamine, asparagine, glutamic acid and aspartic acid) important for endosymbiont-mediated synthesis of essential amino acids. Aphids feeding under eCO2 also produced over three times more honeydew than aphids feeding under ambient CO2 , suggesting they were imbibing more phloem sap at eCO2 . The frequency of ant tending of aphids more than doubled in response to eCO2 . To our knowledge, this is the first study to demonstrate the effects of atmospheric change on an ant-aphid mutualism. In particular, these results highlight how impending changes to concentrations of atmospheric CO2 may alter mutualistic behaviour between animals. These could include positive impacts, as reported here, shifts from mutualism to antagonism, partner switches and mutualism abandonment.},
}
@article {pmid29590405,
year = {2018},
author = {Sinclair, TR and Nogueira, MA},
title = {Selection of host-plant genotype: the next step to increase grain legume N2 fixation activity.},
journal = {Journal of experimental botany},
volume = {69},
number = {15},
pages = {3523-3530},
doi = {10.1093/jxb/ery115},
pmid = {29590405},
issn = {1460-2431},
mesh = {Agriculture ; *Bacteria ; *Bacterial Physiological Phenomena ; Fabaceae/cytology/*genetics/physiology ; Genotype ; Models, Biological ; Nitrogen Fixation/*genetics ; Plant Shoots/genetics/physiology ; Root Nodules, Plant/genetics/physiology ; Soil Microbiology ; Stress, Physiological ; Symbiosis ; Water/*metabolism ; },
abstract = {Symbiotic N2 fixation research thus far has been primarily focused on selection of bacteria. However, little progress in impacting crop yields has resulted from this approach. Bacteria introduced in field soils rarely compete well with indigenous bacteria, including mutated lines selected for high nitrogen fixation capacity. Consequently, introduction of 'elite' bacteria in fields commonly does not result in crop yield increase. This review highlights that the primary regulation of N2 fixation is a result of response of integrated physiological activity at the plant level. Nitrogen feedback from the host plant plays an important role in regulating the N2 fixation rate. Rapid sequestration of fixed nitrogen by the plant is especially important for high N2 fixation activity. In addition, water cycling in the plant between the shoot and nodules plays a key role in sustaining high N2 fixation activity. Therefore, attention in selecting the host-plant genotype is suggested to be the next step to increasing N2 fixation activity of grain legumes.},
}
@article {pmid31618269,
year = {2019},
author = {Moonjely, S and Zhang, X and Fang, W and Bidochka, MJ},
title = {Metarhizium robertsii ammonium permeases (MepC and Mep2) contribute to rhizoplane colonization and modulates the transfer of insect derived nitrogen to plants.},
journal = {PloS one},
volume = {14},
number = {10},
pages = {e0223718},
doi = {10.1371/journal.pone.0223718},
pmid = {31618269},
issn = {1932-6203},
abstract = {The endophytic insect pathogenic fungi (EIPF) Metarhizium promotes plant growth through symbiotic association and the transfer of insect-derived nitrogen. However, little is known about the genes involved in this association and the transfer of nitrogen. In this study, we assessed the involvement of six Metarhizium robertsii genes in endophytic, rhizoplane and rhizospheric colonization with barley roots. Two ammonium permeases (MepC and Mep2) and a urease, were selected since homologous genes in arbuscular mycorrhizal fungi were reported to play a pivotal role in nitrogen mobilization during plant root colonization. Three other genes were selected on the basis on RNA-Seq data that showed high expression levels on bean roots, and these encoded a hydrophobin (Hyd3), a subtilisin-like serine protease (Pr1A) and a hypothetical protein. The root colonization assays revealed that the deletion of urease, hydrophobin, subtilisin-like serine protease and hypothetical protein genes had no impact on endophytic, rhizoplane and rhizospheric colonization at 10 or 20 days. However, the deletion of MepC resulted in significantly increased rhizoplane colonization at 10 days whereas ΔMep2 showed increased rhizoplane colonization at 20 days. In addition, the nitrogen transporter mutants also showed significantly higher 15N incorporation of insect derived nitrogen in barley leaves in the presence of nutrients. Insect pathogenesis assay revealed that disruption of MepC, Mep2, urease did not reduce virulence toward insects. The enhanced rhizoplane colonization of ΔMep2 and ΔMepC and insect derived nitrogen transfer to plant hosts suggests the role of MepC and Mep2 in Metarhizium-plant symbiosis.},
}
@article {pmid31617792,
year = {2019},
author = {Daubech, B and Poinsot, V and Klonowska, A and Capela, D and Chaintreuil, C and Moulin, L and Marchetti, M and Masson-Boivin, C},
title = {noeM, a New Nodulation Gene Involved in the Biosynthesis of Nod Factors with an Open-Chain Oxidized Terminal Residue and in the Symbiosis with Mimosa pudica.},
journal = {Molecular plant-microbe interactions : MPMI},
volume = {},
number = {},
pages = {MPMI06190168R},
doi = {10.1094/MPMI-06-19-0168-R},
pmid = {31617792},
issn = {0894-0282},
abstract = {The β-rhizobium Cupriavidus taiwanensis is a nitrogen-fixing symbiont of Mimosa pudica. Nod factors produced by this species were previously found to be pentameric chitin-oligomers carrying common C18:1 or C16:0 fatty acyl chains, N-methylated and C-6 carbamoylated on the nonreducing terminal N-acetylglucosamine and sulfated on the reducing terminal residue. Here, we report that, in addition, C. taiwanensis LMG19424 produces molecules where the reducing sugar is open and oxidized. We identified a novel nodulation gene located on the symbiotic plasmid pRalta, called noeM, which is involved in this atypical Nod factor structure. noeM encodes a transmembrane protein bearing a fatty acid hydroxylase domain. This gene is expressed during symbiosis with M. pudica and requires NodD and luteolin for optimal expression. The closest noeM homologs formed a separate phylogenetic clade containing rhizobial genes only, which are located on symbiosis plasmids downstream from a nod box. Corresponding proteins, referred to as NoeM, may have specialized in symbiosis via the connection to the nodulation pathway and the spread in rhizobia. noeM was mostly found in isolates of the Mimoseae tribe, and specifically detected in all tested strains able to nodulate M. pudica. A noeM deletion mutant of C. taiwanensis was affected for the nodulation of M. pudica, confirming the role of noeM in the symbiosis with this legume.},
}
@article {pmid31614693,
year = {2019},
author = {Deo, D and Davray, D and Kulkarni, R},
title = {A Diverse Repertoire of Exopolysaccharide Biosynthesis Gene Clusters in Lactobacillus Revealed by Comparative Analysis in 106 Sequenced Genomes.},
journal = {Microorganisms},
volume = {7},
number = {10},
pages = {},
doi = {10.3390/microorganisms7100444},
pmid = {31614693},
issn = {2076-2607},
abstract = {Production of exopolysaccharides (EPS) is one of the unique features of Lactobacillus genus. EPS not only have many physiological roles such as in stress tolerance, quorum sensing and biofilm formation, but also have numerous applications in the food and pharmaceutical industries. In this study, we identified and compared EPS biosynthesis gene clusters in 106 sequenced Lactobacillus genomes representing 27 species. Of the 146 identified clusters, only 41 showed the typical generic organization of genes as reported earlier. Hierarchical clustering showed highly varied nature of the clusters in terms of the gene composition; nonetheless, habitat-wise grouping was observed for the gene clusters from host-adapted and nomadic strains. Of the core genes required for EPS biosynthesis, epsA, B, C, D and E showed higher conservation, whereas gt, wzx and wzy showed high variability in terms of the number and composition of the protein families. Analysis of the distribution pattern of the protein families indicated a higher proportion of mutually exclusive families in clusters from host-adapted and nomadic strains, whereas those from the free-living group had very few unique families. Taken together, this analysis highlights high variability in the EPS gene clusters amongst Lactobacillus with some of their properties correlated to the habitats.},
}
@article {pmid31250035,
year = {2019},
author = {Wang, G and Huang, S and Wang, Y and Cai, S and Yu, H and Liu, H and Zeng, X and Zhang, G and Qiao, S},
title = {Bridging intestinal immunity and gut microbiota by metabolites.},
journal = {Cellular and molecular life sciences : CMLS},
volume = {76},
number = {20},
pages = {3917-3937},
doi = {10.1007/s00018-019-03190-6},
pmid = {31250035},
issn = {1420-9071},
support = {31420103908//National Natural Science Foundation of China/ ; 2017YFD0500506//Key Technologies Research and Development Program/ ; },
mesh = {*Adaptive Immunity ; Amino Acids/immunology/metabolism ; Animals ; Bile Acids and Salts/immunology/metabolism ; Dysbiosis/immunology/*metabolism/microbiology/therapy ; Fatty Acids/immunology/metabolism ; Fecal Microbiota Transplantation ; Gastrointestinal Microbiome/*immunology ; Germ-Free Life/immunology ; Homeostasis/immunology ; Humans ; *Immunity, Innate ; Intestinal Mucosa/immunology/*metabolism/microbiology ; Lymphocytes/immunology/metabolism/microbiology ; Metabolome/*immunology ; Myeloid Cells/immunology/metabolism/microbiology ; Symbiosis/immunology ; },
abstract = {The gastrointestinal tract is the site of nutrient digestion and absorption and is also colonized by diverse, highly mutualistic microbes. The intestinal microbiota has diverse effects on the development and function of the gut-specific immune system, and provides some protection from infectious pathogens. However, interactions between intestinal immunity and microorganisms are very complex, and recent studies have revealed that this intimate crosstalk may depend on the production and sensing abilities of multiple bioactive small molecule metabolites originating from direct produced by the gut microbiota or by the metabolism of dietary components. Here, we review the interplay between the host immune system and the microbiota, how commensal bacteria regulate the production of metabolites, and how these microbiota-derived products influence the function of several major innate and adaptive immune cells involved in modulating host immune homeostasis.},
}
@article {pmid31095275,
year = {2019},
author = {Karimi, S and Askari Seyahooei, M and Izadi, H and Bagheri, A and Khodaygan, P},
title = {Effect of Arsenophonus Endosymbiont Elimination on Fitness of the Date Palm Hopper, Ommatissus lybicus (Hemiptera: Tropiduchidae).},
journal = {Environmental entomology},
volume = {48},
number = {3},
pages = {614-622},
doi = {10.1093/ee/nvz047},
pmid = {31095275},
issn = {1938-2936},
mesh = {Animals ; Enterobacteriaceae ; *Hemiptera ; Insecta ; *Phoeniceae ; Phylogeny ; Symbiosis ; },
abstract = {The date palm hopper, Ommatissus lybicus de Bergevin, is one of the most important pests of the date palm in the Middle East and North Africa. This insect uses its needle-like sucking mouthparts to feed on phloem, which is devoid of most essential amino acids and many vitamins. The absence of essential nutrient in its diet is suggested to be ameliorated by endosymbionts in O. lybicus. Arsenophonus is one of the main bacterial endosymbionts widely prevalent in O. lybicus. In this study, we used antibiotics to eliminate Arsenophonus from O. lybicus originating from three populations (Fin, Qale'e Qazi, and Roodan) and studied the effects on the fitness of the pest. Our results revealed that the removal of Arsenophonus increased the developmental time of the immature stages and reduced the values of different life-history parameters including nymphal survival rate and adult longevity in the host. Furthermore, elimination of Arsenophonus completely obliterated offspring production in all O. lybicus populations investigated. These results confirm the dependency of O. lybicus on Arsenophonus for fitness and give a new insight regarding the possibility of symbiotic control of O. lybicus.},
}
@article {pmid31022695,
year = {2018},
author = {Powell, DA and Ma, M and So, M and Frelinger, JA},
title = {The Commensal Neisseria musculi Modulates Host Innate Immunity To Promote Oral Colonization.},
journal = {ImmunoHorizons},
volume = {2},
number = {9},
pages = {305-313},
doi = {10.4049/immunohorizons.1800070},
pmid = {31022695},
issn = {2573-7732},
support = {R56 AI124665/AI/NIAID NIH HHS/United States ; },
mesh = {Adaptive Immunity ; Animals ; Escherichia coli ; Gram-Negative Bacterial Infections/*immunology ; Host Microbial Interactions ; Immunity, Innate ; Interleukin-6/deficiency/immunology ; Macrophages/immunology ; Mice ; Mice, Inbred C57BL ; Mice, Inbred Strains ; Mice, Knockout ; Neisseria/*immunology ; Symbiosis/immunology ; Toll-Like Receptor 4 ; },
abstract = {Neisseria musculi, isolated from the oral cavity of wild-caught mice, does not colonize most inbred mouse strains. N. musculi does weakly (50%) colonize C57BL/6J (B6) mice but readily colonizes CAST/EiJ (CAST) mice. In this study, we examined whether differences in the CAST and B6 host response could elucidate mechanisms governing N. musculi colonization. In vivo stimulation of B6 or CAST splenocytes with wild type (WT) Neisseria or Escherichia coli LPS showed that CAST mice had a blunted inflammatory response, producing significantly lower levels of IL-6 than B6 mice. The use of specific genetic knockouts highlighted a need for an intact innate immune system to prevent colonization. B6-RAG-1-/- mice were colonized at a similar rate as WT B6 mice, whereas B6-MyD88-/- and TLR4-/- mice were readily colonized like CAST (100%) mice. Sequence analysis revealed a unique point mutation in TLR4 in CAST mice. However, crosses to TLR4-/- mice and analysis of recombinant inbred Collaborative Cross mice showed that TLR4 from CAST mice was not sufficient to allow Neisseria colonization. In vitro stimulation of B6 bone marrow-derived macrophages or splenocytes with WT Neisseria yielded low levels of IL-6 compared with LPS stimulation. Surprisingly, UV-inactivated Neisseria induced high levels of IL-6, suggesting suppression of IL-6 production is an active bacterial process. Consistent with a critical role for IL-6 in preventing colonization, mice deficient for the IL-6 receptor were efficiently colonized, indicating host IL-6 production plays a critical role in determining host colonization susceptibility.},
}
@article {pmid31613012,
year = {2019},
author = {Panneerselvam, P and Sahoo, S and Senapati, A and Kumar, U and Mitra, D and Parameswaran, C and Anandan, A and Kumar, A and Jahan, A and Nayak, AK},
title = {Understanding interaction effect of arbuscular mycorrhizal fungi in rice under elevated carbon dioxide conditions.},
journal = {Journal of basic microbiology},
volume = {},
number = {},
pages = {},
doi = {10.1002/jobm.201900294},
pmid = {31613012},
issn = {1521-4028},
abstract = {Arbuscular mycorrhizal fungi (AMF), particularly the Glomerales group, play a paramount role in plant nutrient uptake, and abiotic and biotic stress management in rice, but recent evidence revealed that elevated CO2 concentration considerably reduces the Glomerales group in soil. In view of this, the present study was initiated to understand the interaction effect of native Glomerales species application in rice plants (cv. Naveen) under elevated CO2 concentrations (400 ± 10, 550 ± 20, and 700 ± 20 ppm) in open-top chambers. Three different modes of application of the AMF inoculum were evaluated, of which, combined application of AMF at the seedling production and transplanting stages showed increased AMF colonization, which significantly improved grain yield by 25.08% and also increased uptake of phosphorus by 18.2% and nitrogen by 49.5%, as observed at 700-ppm CO2 concentration. Organic acids secretion in rice root increased in AMF-inoculated plants exposed to 700-ppm CO2 concentration. To understand the overall effect of CO2 elevation on AMF interaction with the rice plant, principal component and partial least square regression analysis were performed, which found both positive and negative responses under elevated CO2 concentration.},
}
@article {pmid31612356,
year = {2019},
author = {Singh, MP and Saxena, M and Saimbi, CS and Siddiqui, MH and Roy, R},
title = {Post-periodontal surgery propounds early repair salivary biomarkers by 1H NMR based metabolomics.},
journal = {Metabolomics : Official journal of the Metabolomic Society},
volume = {15},
number = {11},
pages = {141},
doi = {10.1007/s11306-019-1593-3},
pmid = {31612356},
issn = {1573-3890},
support = {5/4/2-7-12-NCD-II//Indian Council of Medical Research/ ; },
abstract = {INTRODUCTION: Oral microflora is a well-orchestrated and acts as a sequential defense mechanism for any infection related to oral disease. Chronic periodontitis is a disease of a microbial challenge to symbiosis and homeostasis. Periodontal surgery is the most promising cure with repair process during periodontal regeneration. It has an encouraging outcome in terms of early recovery biomarkers.<br><br>OBJECTIVE: Saliva of periodontal surgery subjects with the chronic periodontitis have been evaluated by 1H NMR spectroscopy in search of possible early metabolic differences that could be obtained in order to see the eradication of disease which favours the symbiotic condition.<br><br>METHOD: The study employed 1H NMR spectroscopy on 176 human saliva samples in search of distinctive differences and their spectral data were further subjected to multivariate and quantitative analysis.<br><br>RESULT: The 1H NMR study of periodontal surgery samples shows clear demarcation and profound metabolic differences when compared with the diseased condition. Several metabolites such as lactate, ethanol, succinate, and glutamate were found to be of higher significance in periodontal surgery in contrast to chronic periodontitis subjects. The PLS-DA model of the studied group resulted in R2 of 0.83 and Q2 of 0.70.<br><br>CONCLUSION: Significant metabolites could be considered as early repair markers for chronic periodontitis disease as they are being restored to achieve symbiosis. The study, therefore, concluded the early recovery process of the diseased subjects with the restoration of possible metabolomic profile similar to the healthy controls.},
}
@article {pmid31611899,
year = {2019},
author = {Fiorilli, V and Wang, JY and Bonfante, P and Lanfranco, L and Al-Babili, S},
title = {Apocarotenoids: Old and New Mediators of the Arbuscular Mycorrhizal Symbiosis.},
journal = {Frontiers in plant science},
volume = {10},
number = {},
pages = {1186},
doi = {10.3389/fpls.2019.01186},
pmid = {31611899},
issn = {1664-462X},
abstract = {Plants utilize hormones and other small molecules to trigger and coordinate their growth and developmental processes, adapt and respond to environmental cues, and communicate with surrounding organisms. Some of these molecules originate from carotenoids that act as universal precursors of bioactive metabolites arising through oxidation of the carotenoid backbone. This metabolic conversion produces a large set of compounds known as apocarotenoids, which includes the plant hormones abscisic acid (ABA) and strigolactones (SLs) and different signaling molecules. An increasing body of evidence suggests a crucial role of previously identified and recently discovered carotenoid-derived metabolites in the communication with arbuscular mycorrhizal (AM) fungi and the establishment of the corresponding symbiosis, which is one of the most relevant plant-fungus mutualistic interactions in nature. In this review, we provide an update on the function of apocarotenoid hormones and regulatory metabolites in AM symbiosis, highlighting their effect on both partners.},
}
@article {pmid29934603,
year = {2018},
author = {Oron, S and Abramovich, S and Almogi-Labin, A and Woeger, J and Erez, J},
title = {Depth related adaptations in symbiont bearing benthic foraminifera: New insights from a field experiment on Operculina ammonoides.},
journal = {Scientific reports},
volume = {8},
number = {1},
pages = {9560},
pmid = {29934603},
issn = {2045-2322},
mesh = {*Adaptation, Physiological ; Chlorophyll/metabolism ; Convolvulaceae/metabolism/*microbiology ; Foraminifera/*physiology ; Fossils ; Laboratories ; Light ; *Symbiosis ; Temperature ; },
abstract = {Large benthic foraminifera (LBF) are marine calcifying protists that commonly harbor algae as symbionts. These organisms are major calcium carbonate producers and important contributors to primary production in the photic zones. Light is one of the main known factors limiting their distribution, and species of this group developed specific mechanisms that allow them to occupy different habitats across the light gradient. Operculina ammonoides (Gronovius, 1781) is a planispiral LBF that has two main shell morphotypes, thick involute and flat evolute. Earlier studies suggested morphologic changes with variation in water depth and presumably light. In this study, specimens of the two morphotypes were placed in the laboratory under artificial low light and near the sea floor at depths of 15 m, 30 m, and 45 m in the Gulf of Aqaba-Eilat for 23 days. Differences in growth and symbionts content were evaluated using weight, size, and chlorophyll a. Our results show that O. ammonoides exhibit morphological plasticity when constructing thinner chambers after relocation to low light conditions, and adding more weight per area after relocation to high light conditions. In addition, O. ammonoides exhibited chlorophyll content adaptation to a certain range of light conditions, and evolute specimens that were acclimatized to very low light did not survive relocation to a high light environment, possibly due to photo-oxidative stress.},
}
@article {pmid29844498,
year = {2018},
author = {Förderer, M and Rödder, D and Langer, MR},
title = {Patterns of species richness and the center of diversity in modern Indo-Pacific larger foraminifera.},
journal = {Scientific reports},
volume = {8},
number = {1},
pages = {8189},
pmid = {29844498},
issn = {2045-2322},
mesh = {Animals ; Anthozoa/*physiology ; *Biodiversity ; Carbonates/metabolism ; Climate Change ; *Coral Reefs ; Ecosystem ; Foraminifera/*physiology ; Indian Ocean ; Models, Biological ; Pacific Ocean ; Symbiosis ; Tropical Climate ; },
abstract = {Symbiont-bearing Larger Benthic Foraminifera (LBF) are ubiquitous components of shallow tropical and subtropical environments and contribute substantially to carbonaceous reef and shelf sediments. Climate change is dramatically affecting carbonate producing organisms and threatens the diversity and structural integrity of coral reef ecosystems. Recent invertebrate and vertebrate surveys have identified the Coral Triangle as the planet's richest center of marine life delineating the region as a top priority for conservation. We compiled and analyzed extensive occurrence records for 68 validly recognized species of LBF from the Indian and Pacific Ocean, established individual range maps and applied Minimum Convex Polygon (MCP) and Species Distribution Model (SDM) methodologies to create the first ocean-wide species richness maps. SDM output was further used for visualizing latitudinal and longitudinal diversity gradients. Our findings provide strong support for assigning the tropical Central Indo-Pacific as the world's species-richest marine region with the Central Philippines emerging as the bullseye of LBF diversity. Sea surface temperature and nutrient content were identified as the most influential environmental constraints exerting control over the distribution of LBF. Our findings contribute to the completion of worldwide research on tropical marine biodiversity patterns and the identification of targeting centers for conservation efforts.},
}
@article {pmid29648609,
year = {2018},
author = {Osborne, SJ and McMillan, VE and White, R and Hammond-Kosack, KE},
title = {Elite UK winter wheat cultivars differ in their ability to support the colonization of beneficial root-infecting fungi.},
journal = {Journal of experimental botany},
volume = {69},
number = {12},
pages = {3103-3115},
pmid = {29648609},
issn = {1460-2431},
support = {BB/J/00426X/1/BB_/Biotechnology and Biological Sciences Research Council/United Kingdom ; BB/P016855/1/BB_/Biotechnology and Biological Sciences Research Council/United Kingdom ; BB/J014508/1/BB_/Biotechnology and Biological Sciences Research Council/United Kingdom ; BB/I002545/1/BB_/Biotechnology and Biological Sciences Research Council/United Kingdom ; },
mesh = {Ascomycota/*physiology ; England ; *Soil Microbiology ; *Symbiosis ; Triticum/*microbiology/physiology ; },
abstract = {In numerous countries, Gaeumannomyces species, within the Magnaporthaceae family, have previously been implicated in the suppression of take-all root disease in wheat. A UK arable isolate collection (n=47) was gathered and shown to contain Gaeumannomyces hyphopodioides and an unnamed Magnaporthaceae species. A novel seedling pot bioassay revealed that both species had a similar ability to colonize cereal roots; however, rye (Secale cereale) was only poorly colonized by the Magnaporthaceae species. To evaluate the ability of 40 elite UK winter wheat cultivars to support soil inoculum of beneficial soil-dwelling fungi, two field experiments were carried out using a naturally infested arable site in south-east England. The elite cultivars grown in the first wheat situation differed in their ability to support G. hyphopodioides inoculum, measured by colonization on Hereward as the subsequent wheat in a seedling soil core bioassay. In addition, the root colonization ability of G. hyphopodioides was influenced by the choice of the second wheat cultivar. Nine cultivars supported the colonization of the beneficial root fungus. Our findings provide evidence of complex host genotype-G. hyphopodioides interactions occurring under field conditions. This new knowledge could provide an additional soil-based crop genetic management strategy to help combat take-all root disease.},
}
@article {pmid31610133,
year = {2019},
author = {Biedermann, PHW and Vega, FE},
title = {Ecology and Evolution of Insect-Fungus Mutualisms.},
journal = {Annual review of entomology},
volume = {},
number = {},
pages = {},
doi = {10.1146/annurev-ento-011019-024910},
pmid = {31610133},
issn = {1545-4487},
abstract = {The evolution of a mutualism requires reciprocal interactions whereby one species provides a service that the other species cannot perform or performs less efficiently. Services exchanged in insect-fungus mutualisms include nutrition, protection, and dispersal. In ectosymbioses, which are the focus of this review, fungi can be consumed by insects or can degrade plant polymers or defensive compounds, thereby making a substrate available to insects. They can also protect against environmental factors and produce compounds antagonistic to microbial competitors. Insects disperse fungi and can also provide fungal growth substrates and protection. Insect-fungus mutualisms can transition from facultative to obligate, whereby each partner is no longer viable on its own. Obligate dependency has (a) resulted in the evolution of morphological adaptations in insects and fungi, (b) driven the evolution of social behaviors in some groups of insects, and (c) led to the loss of sexuality in some fungal mutualists. Expected final online publication date for the Annual Review of Entomology, Volume 65 is January 7, 2020. Please see http://www.annualreviews.org/page/journal/pubdates for revised estimates.},
}
@article {pmid31610071,
year = {2019},
author = {Benezech, C and Doudement, M and Gourion, B},
title = {Legumes tolerance to Rhizobia is not always observed and not always deserved.},
journal = {Cellular microbiology},
volume = {},
number = {},
pages = {e13124},
doi = {10.1111/cmi.13124},
pmid = {31610071},
issn = {1462-5822},
abstract = {Rhizobia display dual lifestyle. These bacteria are soil inhabitants but can also elicit the formation of a special niche on the root of legume plants, the nodules. In such organs, rhizobia can promote the growth of their host by providing them nitrogen they captured from atmosphere. All along the infection process, the plant innate immunity has to be controlled to maintain compatible interaction. However, nodulation does not always result in profit for the plant as compatible interactions include both nitrogen-fixing and non-fixing associations. In recent years, our knowledge on the mechanisms involved in the control of plant innate immunity during rhizobia-legume interactions has greatly improved notably by the identification of bacterial and plant genes activating or suppressing the plant defenses. Surprisingly results also demonstrated that in some cases plant defense reactions result in abortion of the nodulation process despite that the rhizobial strain has all the genetic potential to establish mutualism. In such situation, experimental evolution approaches highlighted possible rapid switches of incompatible rhizobia either to mutualistic or parasitic behavior. Here we review this recent literature.},
}
@article {pmid31608994,
year = {2019},
author = {Desai, D and Pethe, P},
title = {Polycomb repressive complex 1: Regulators of neurogenesis from embryonic to adult stage.},
journal = {Journal of cellular physiology},
volume = {},
number = {},
pages = {},
doi = {10.1002/jcp.29299},
pmid = {31608994},
issn = {1097-4652},
support = {//SVKM's NMIMS (deemed-to-be) University/ ; },
abstract = {Development of vertebrate nervous system is a complex process which involves differential gene expression and disruptions in this process or in the mature brain, may lead to neurological disorders and diseases. Extensive work that spanned several decades using rodent models and recent work on stem cells have helped uncover the intricate process of neuronal differentiation and maturation. There are various morphological changes, genetic and epigenetic modifications which occur during normal mammalian neural development, one of the chromatin modifications that controls vital gene expression are the posttranslational modifications on histone proteins, that controls accessibility of translational machinery. Among the histone modifiers, polycomb group proteins (PcGs), such as Ezh2, Eed and Suz12 form large protein complexes-polycomb repressive complex 2 (PRC2); while Ring1b and Bmi1 proteins form core of PRC1 along with accessory proteins such as Cbx, Hph, Rybp and Pcgfs catalyse histone modifications such as H3K27me3 and H2AK119ub1. PRC1 proteins are known to play critical role in X chromosome inactivation in females but they also repress the expression of key developmental genes and tightly regulate the mammalian neuronal development. In this review we have discussed the signalling pathways, morphogens and nuclear factors that initiate, regulate and maintain cells of the nervous system. Further, we have extensively reviewed the recent literature on the role of Ring1b and Bmi1 in mammalian neuronal development and differentiation; as well as highlighted questions that are still unanswered.},
}
@article {pmid31608569,
year = {2019},
author = {Feng, Z and Liu, X and Feng, G and Zhu, H and Yao, Q},
title = {Linking lipid transfer with reduced arbuscule formation in tomato roots colonized by arbuscular mycorrhizal fungus under low pH stress.},
journal = {Environmental microbiology},
volume = {},
number = {},
pages = {},
doi = {10.1111/1462-2920.14810},
pmid = {31608569},
issn = {1462-2920},
abstract = {Arbuscules are the core structures of arbuscular mycorrhizae (AM), and arbuscule development is regulated by environmental stress, e.g., low pH. Recent studies indicate that lipid transfer from plants is essential for AM fungal colonization; however, the role of lipid transfer in arbuscule formation and the dynamics of lipid accumulation in arbuscules under low pH stress are far from well understood. In the symbiosis of tomato and Rhizophagus intraradices under contrasting pH conditions (pH 4.5 vs. pH 6.5), we investigated arbuscule formation, nutrient uptake, alkaline phosphatase activity, and lipid accumulation; examined the gene expression involved in phosphate transport, lipid biosynthesis and transfer, and sugar metabolism; and visualized the lipid dynamics in arbuscules. Low pH greatly inhibited arbuscule formation, in parallel with reduced phospholipid fatty acids (PLFAs) accumulation in AM fungus and decreased P uptake. This reduction was supported by the decreased expression of plant genes encoding lipid biosynthesis and transfer. More degenerating arbuscules were observed under low pH conditions, and neutral lipid fatty acids (NLFAs) accumulated only in degenerating arbuscules. These data reveal that, under low pH stress, reduced lipid transfer from hosts to AM fungi is responsible for the inhibited arbuscule formation. This article is protected by copyright. All rights reserved.},
}
@article {pmid31608089,
year = {2019},
author = {King, E and Wallner, A and Rimbault, I and Barrachina, C and Klonowska, A and Moulin, L and Czernic, P},
title = {Monitoring of Rice Transcriptional Responses to Contrasted Colonizing Patterns of Phytobeneficial Burkholderia s.l. Reveals a Temporal Shift in JA Systemic Response.},
journal = {Frontiers in plant science},
volume = {10},
number = {},
pages = {1141},
doi = {10.3389/fpls.2019.01141},
pmid = {31608089},
issn = {1664-462X},
abstract = {In the context of plant-pathogen and plant-mutualist interactions, the underlying molecular bases associated with host colonization have been extensively studied. However, it is not the case for non-mutualistic beneficial interactions or associative symbiosis with plants. Particularly, little is known about the transcriptional regulations associated with the immune tolerance of plants towards beneficial microbes. In this context, the study of the Burkholderia rice model is very promising to describe the molecular mechanisms involved in associative symbiosis. Indeed, several species of the Burkholderia sensu lato (s.l.) genus can colonize rice tissues and have beneficial effects; particularly, two species have been thoroughly studied: Burkholderia vietnamiensis and Paraburkholderia kururiensis. This study aims to compare the interaction of these species with rice and especially to identify common or specific plant responses. Therefore, we analyzed root colonization of the rice cultivar Nipponbare using DsRed-tagged bacterial strains and produced the transcriptomes of both roots and leaves 7 days after root inoculation. This led us to the identification of a co-expression jasmonic acid (JA)-related network exhibiting opposite regulation in response to the two strains in the leaves of inoculated plants. We then monitored by quantitative polymerase chain reaction (qPCR) the expression of JA-related genes during time course colonization by each strain. Our results reveal a temporal shift in this JA systemic response, which can be related to different colonization strategies of both strains.},
}
@article {pmid31608044,
year = {2019},
author = {Romero-Contreras, YJ and Ramírez-Valdespino, CA and Guzmán-Guzmán, P and Macías-Segoviano, JI and Villagómez-Castro, JC and Olmedo-Monfil, V},
title = {Tal6 From Trichoderma atroviride Is a LysM Effector Involved in Mycoparasitism and Plant Association.},
journal = {Frontiers in microbiology},
volume = {10},
number = {},
pages = {2231},
doi = {10.3389/fmicb.2019.02231},
pmid = {31608044},
issn = {1664-302X},
abstract = {LysM effectors play a relevant role during the plant colonization by successful phytopathogenic fungi, since they enable them to avoid either the triggering of plant defense mechanisms or their attack effects. Tal6, a LysM protein from Trichoderma atroviride, is capable of binding to complex chitin. However, until now its biological function is not completely known, particularly its participation in plant-Trichoderma interactions. We obtained T. atroviride Tal6 null mutant and Tal6 overexpressing strains and determined the role played by this protein during Trichoderma-plant interaction and mycoparasitism. LysM effector Tal6 from T. atroviride protects the hyphae from chitinases by binding to chitin of the fungal cell wall, increases the fungus mycoparasitic capacity, and modulates the activation of the plant defense system. These results show that beneficial fungi also employ LysM effectors to improve their association with plants.},
}
@article {pmid31608043,
year = {2019},
author = {Gifford, I and Vance, S and Nguyen, G and Berry, AM},
title = {A Stable Genetic Transformation System and Implications of the Type IV Restriction System in the Nitrogen-Fixing Plant Endosymbiont Frankia alni ACN14a.},
journal = {Frontiers in microbiology},
volume = {10},
number = {},
pages = {2230},
doi = {10.3389/fmicb.2019.02230},
pmid = {31608043},
issn = {1664-302X},
abstract = {Genus Frankia is comprised primarily of nitrogen-fixing actinobacteria that form root nodule symbioses with a group of hosts known as the actinorhizal plants. These plants are evolutionarily closely related to the legumes that are nodulated by the rhizobia. Both host groups utilize homologs of nodulation genes for root-nodule symbiosis, derived from common plant ancestors. The corresponding endosymbionts, Frankia and the rhizobia, however, are distantly related groups of bacteria, leading to questions about their symbiotic mechanisms and evolutionary history. To date, a stable system of electrotransformation has been lacking in Frankia despite numerous attempts by research groups worldwide. We have identified type IV methyl-directed restriction systems, highly-expressed in a range of actinobacteria, as a likely barrier to Frankia transformation. Here we report the successful electrotransformation of the model strain F. alni ACN14a with an unmethylated, broad host-range replicating plasmid, expressing chloramphenicol-resistance for selection and GFP as a marker of gene expression. This system circumvented the type IV restriction barrier and allowed the stable maintenance of the plasmid. During nitrogen limitation, Frankia differentiates into two cell types: the vegetative hyphae and nitrogen-fixing vesicles. When the expression of egfp under the control of the nif gene cluster promoter was localized using fluorescence imaging, the expression of nitrogen fixation in nitrogen-limited culture was localized in Frankia vesicles but not in hyphae. The ability to separate gene expression patterns between Frankia hyphae and vesicles will enable deeper comparisons of molecular signaling and metabolic exchange between Frankia-actinorhizal and rhizobia-legume symbioses to be made, and may broaden potential applications in agriculture. Further downstream applications are possible, including gene knock-outs and complementation, to open up a range of experiments in Frankia and its symbioses. Additionally, in the transcriptome of F. alni ACN14a, type IV restriction enzymes were highly expressed in nitrogen-replete culture but their expression strongly decreased during symbiosis. The down-regulation of type IV restriction enzymes in symbiosis suggests that horizontal gene transfer may occur more frequently inside the nodule, with possible new implications for the evolution of Frankia.},
}
@article {pmid31608037,
year = {2019},
author = {Antoine, R and Rivera-Millot, A and Roy, G and Jacob-Dubuisson, F},
title = {Relationships Between Copper-Related Proteomes and Lifestyles in β Proteobacteria.},
journal = {Frontiers in microbiology},
volume = {10},
number = {},
pages = {2217},
doi = {10.3389/fmicb.2019.02217},
pmid = {31608037},
issn = {1664-302X},
abstract = {Copper is an essential transition metal whose redox properties are used for a variety of enzymatic oxido-reductions and in electron transfer chains. It is also toxic to living beings, and therefore its cellular concentration must be strictly controlled. We have performed in silico analyses of the predicted proteomes of more than one hundred species of β proteobacteria to characterize their copper-related proteomes, including cuproproteins, i.e., proteins with active-site copper ions, copper chaperones, and copper-homeostasis systems. Copper-related proteomes represent between 0 and 1.48% of the total proteomes of β proteobacteria. The numbers of cuproproteins are globally proportional to the proteome sizes in all phylogenetic groups and strongly linked to aerobic respiration. In contrast, environmental bacteria have considerably larger proportions of copper-homeostasis systems than the other groups of bacteria, irrespective of their proteome sizes. Evolution toward commensalism, obligate, host-restricted pathogenesis or symbiosis is globally reflected in the loss of copper-homeostasis systems. In endosymbionts, defense systems and copper chaperones have disappeared, whereas residual cuproenzymes are electron transfer proteins for aerobic respiration. Lifestyle is thus a major determinant of the size and composition of the copper-related proteome, and it is particularly reflected in systems involved in copper homeostasis. Analyses of the copper-related proteomes of a number of species belonging to the Burkholderia, Bordetella, and Neisseria genera indicates that commensals are in the process of shedding their copper-homeostasis systems and chaperones to greater extents yet than pathogens.},
}
@article {pmid31607710,
year = {2019},
author = {Kavadi, SN},
title = {V. R. Khanolkar and the Indian Cancer Research Centre, 1952-1962.},
journal = {Indian journal of cancer},
volume = {56},
number = {4},
pages = {364-367},
doi = {10.4103/ijc.IJC_14_19},
pmid = {31607710},
issn = {1998-4774},
abstract = {This note presents a brief account of the ideas and efforts of V.R. Khanolkar in the period 1952-1962 to develop the Indian Cancer Research Centre into a &quot;center of excellence&quot;. Khanolkar, who is recognized as a pioneer in cancer research in India, focused on developing multidisciplinary medical research and mentored and trained young medical researchers. He sought and received aid from the Rockefeller Foundation, which was keen to support him in this task.},
}
@article {pmid30418562,
year = {2019},
author = {Knobloch, S and Jóhannsson, R and Marteinsson, V},
title = {Bacterial diversity in the marine sponge Halichondria panicea from Icelandic waters and host-specificity of its dominant symbiont &quot;Candidatus Halichondribacter symbioticus&quot;.},
journal = {FEMS microbiology ecology},
volume = {95},
number = {1},
pages = {},
doi = {10.1093/femsec/fiy220},
pmid = {30418562},
issn = {1574-6941},
mesh = {Animals ; Bacteria/classification/genetics/*isolation &amp; purification ; Bacterial Physiological Phenomena ; *Biodiversity ; DNA, Bacterial/genetics ; *Host Specificity ; Iceland ; Phylogeny ; Porifera/*microbiology ; RNA, Ribosomal, 16S/genetics ; Seawater/*microbiology ; Sequence Analysis, DNA ; *Symbiosis ; },
abstract = {Marine sponges can harbour diverse bacteria that contribute to host metabolism and defence. Identifying these stable members of sponge bacterial communities remains a necessary step in understanding their ecological roles and underlying co-evolutionary processes. In this study, we applied high-throughput sequencing of 16S rRNA gene amplicons, ribosomal nucleotide variant analysis and fluorescence in situ hybridisation to characterise the core members of the bacterial community in the marine sponge Halichondria panicea from Icelandic waters. We show that the core bacterial community across all samples consisted of a single, dominant bacterial taxon, for which we propose a candidate status 'Candidatus Halichondribacter symbioticus'. Comparison against public databases showed that 'Ca. H. symbioticus' is both a highly abundant specialist in H. panicea and a low abundant opportunist in other sponge species. Additionally, H. panicea with and without 'Ca. H. symbioticus' co-exist in similar locations in the North Atlantic. This dichotomy paired with the presence of geographically distinct ribosomal sequence variants of the symbiont make H. panicea an interesting sponge species for studying sponge-symbiont co-evolution and functional interactions.},
}
@article {pmid29891919,
year = {2018},
author = {Balvín, O and Roth, S and Talbot, B and Reinhardt, K},
title = {Co-speciation in bedbug Wolbachia parallel the pattern in nematode hosts.},
journal = {Scientific reports},
volume = {8},
number = {1},
pages = {8797},
pmid = {29891919},
issn = {2045-2322},
mesh = {Animals ; Bedbugs/*microbiology ; Biosynthetic Pathways/genetics ; Biotin/biosynthesis ; *Genetic Speciation ; *Symbiosis ; Wolbachia/*classification/genetics/*isolation &amp; purification/metabolism ; },
abstract = {Wolbachia bacteria, vertically transmitted intracellular endosymbionts, are associated with two major host taxa in which they show strikingly different symbiotic modes. In some taxa of filarial nematodes, where Wolbachia are strictly obligately beneficial to the host, they show complete within- and among-species prevalence as well as co-phylogeny with their hosts. In arthropods, Wolbachia usually are parasitic; if beneficial effects occurs, they can be facultative or obligate, related to host reproduction. In arthropods, the prevalence of Wolbachia varies within and among taxa, and no co-speciation events are known. However, one arthropod species, the common bedbug Cimex lectularius was recently found to be dependent on the provision of biotin and riboflavin by Wolbachia, representing a unique case of Wolbachia providing nutritional and obligate benefits to an arthropod host, perhaps even in a mutualistic manner. Using the presence of presumably functional biotin gene copies, our study demonstrates that the obligate relationship is maintained at least in 10 out of 15 species of the genera Cimex and Paracimex. The remaining five species harboured Wolbachia as well, demonstrating the first known case of 100% prevalence of Wolbachia among higher arthropod taxa. Moreover, we show the predicted co-cladogenesis between Wolbachia and their bedbug hosts, also as the first described case of Wolbachia co-speciation in arthropods.},
}
@article {pmid29700426,
year = {2018},
author = {Aira, M and Pérez-Losada, M and Domínguez, J},
title = {Diversity, structure and sources of bacterial communities in earthworm cocoons.},
journal = {Scientific reports},
volume = {8},
number = {1},
pages = {6632},
pmid = {29700426},
issn = {2045-2322},
mesh = {Animals ; *Bacteria/classification/genetics ; *Biodiversity ; *Microbiota ; Oligochaeta/*microbiology ; Symbiosis ; },
abstract = {Animals start interactions with the bacteria that will constitute their microbiomes at embryonic stage. After mating, earthworms produce cocoons externally which will be colonized with bacteria from their parents and the environment. Due to the key role bacterial symbionts play on earthworm fitness, it is important to study bacterial colonization during cocoon formation. Here we describe the cocoon microbiome of the earthworms Eisenia andrei and E. fetida, which included 275 and 176 bacterial species, respectively. They were dominated by three vertically-transmitted symbionts, Microbacteriaceae, Verminephrobacter and Ca. Nephrothrix, which accounted for 88% and 66% of the sequences respectively. Verminephrobacter and Ca. Nephrothrix showed a high rate of sequence variation, suggesting that they could be biparentally acquired during mating. The other bacterial species inhabiting the cocoons came from the bedding, where they accounted for a small fraction of the diversity (27% and 7% of bacterial species for E. andrei and E. fetida bedding). Hence, earthworm cocoon microbiome includes a large fraction of the vertically-transmitted symbionts and a minor fraction, but more diverse, horizontally and non-randomly acquired from the environment. These data suggest that horizontally-transmitted bacteria to cocoons may play an important role in the adaptation of earthworms to new environments or diets.},
}
@article {pmid29588209,
year = {2018},
author = {Goerzen, DW and Erlandson, MA},
title = {Infection of the chalcid parasitoid Pteromalus venustus Walker (Hymenoptera: Pteromalidae) with the male-killing symbiont Arsenophonus nasoniae (Gamma-Proteobacteria: Enterobacteriaceae).},
journal = {Journal of invertebrate pathology},
volume = {154},
number = {},
pages = {24-28},
doi = {10.1016/j.jip.2018.03.013},
pmid = {29588209},
issn = {1096-0805},
mesh = {Animals ; Bees/microbiology ; Biological Control Agents ; Enterobacteriaceae/*physiology ; Female ; Host-Pathogen Interactions ; Hymenoptera/*microbiology ; Male ; Sex Ratio ; Symbiosis ; },
abstract = {The male-killing symbiont Arsenophonus nasoniae is a gamma-proteobacterium that infects parasitic wasps; the male progeny of infected females exhibit increased embryonic death. In this study, we examined methods to horizontally infect Pteromalus venustus (a parasitoid infesting populations of the alfalfa leafcutting bee Megachile rotundata) with A. nasoniae. We then tested the success of these methods via semi-quantitative PCR and quantitative digital PCR, using a molecular marker specific to A. nasoniae. Controlled parasitoid mating experiments were then undertaken to determine whether infections of A. nasoniae in P. venustus induce the male-killing phenotype as has been reported for other host species; evidence of this male-killing phenotype was observed in the current study. Over the course of the eight parasitoid generations following introduction of A. nasoniae infection in P. venustus, the male component of the parasitoid sex ratio was substantially reduced in the infected population (1.05 ♂: 1.00 ♀) compared to the control population (2.46 ♂: 1.00 ♀). Establishment of stable A. nasoniae infections in P. venustus populations could lower the proportion of male progeny, thus negatively impacting the mating success of females, and reducing overall populations of the parasitoid in alfalfa leafcutting bee populations.},
}
@article {pmid31605615,
year = {2019},
author = {Carrère, S and Verdenaud, M and Gough, C and Gouzy, J and Gamas, P},
title = {LeGOO: An Expertized Knowledge Database for the Model Legume Medicago truncatula.},
journal = {Plant &amp; cell physiology},
volume = {},
number = {},
pages = {},
doi = {10.1093/pcp/pcz177},
pmid = {31605615},
issn = {1471-9053},
abstract = {Medicago truncatula was proposed, about three decades ago, as a model legume to study the Rhizobium-legume symbiosis. It has now been adopted to study a wide range of biological questions, including various developmental processes (in particular root, symbiotic nodule and seed development), symbiotic (nitrogen-fixing and arbuscular mycorrhizal endosymbioses) and pathogenic interactions, as well as responses to abiotic stress. With a number of tools and resources set up in M. truncatula for omics, genetics and reverse genetics approaches, massive amounts of data have been produced, as well as four genome sequence releases. Many of these data were generated with heterogeneous tools, notably for transcriptomics studies, and are consequently difficult to integrate. This issue is addressed by the LeGOO (for Legume Graph-Oriented Organizer) knowledge base (https://www.legoo.org), which finds the correspondence between the multiple identifiers of the same gene. Furthermore, an important goal of LeGOO is to collect and represent biological information from peer-reviewed publications, whatever the technical approaches used to obtain this information. The information is modeled in a graph-oriented database, which enables flexible representation, with currently over 200,000 relations retrieved from 298 publications. LeGOO also provides the user with mining tools, including links to the Mt5.0 genome browser and associated information (on gene functional annotation, expression, methylome, natural diversity and available insertion mutants), as well as tools to navigate through different model species. LeGOO is, therefore, an innovative database that will be useful to the Medicago and legume community to better exploit the wealth of data produced on this model species.},
}
@article {pmid31603616,
year = {2019},
author = {Chen, B and Xie, S and Zhang, X and Zhang, N and Feng, H and Sun, C and Lu, X and Shao, Y},
title = {Gut microbiota metabolic potential correlates with body size between mulberry-feeding lepidopteran pest species.},
journal = {Pest management science},
volume = {},
number = {},
pages = {},
doi = {10.1002/ps.5642},
pmid = {31603616},
issn = {1526-4998},
abstract = {BACKGROUND: Many insect pests rely on microbial symbionts to obtain nutrients or for defence, thereby allowing them to exploit novel food sources and degrade environmental xenobiotics including pesticides. Although Lepidoptera is one of the most diverse insect taxa and includes important agricultural pests, their microbiotas have not been studied much, particularly functional traits. Here, we provide a comprehensive characterization of the gut microbiota across multiple mulberry-feeding lepidopteran species, resolving both community structure and metabolic potential.<br><br>RESULTS: Our results indicate abundant bacteria inside the gut of larval Lepidoptera. However, even though they were fed the same diet, the structures of the bacterial communities differed in four major mulberry pest species, suggesting host-specific effects on microbial associations. Community-level metabolic reconstructions further showed that despite taxonomic composition varied greatly, carbohydrate and amino acid metabolism and membrane transporter were key functional capabilities of gut bacteria in all samples, which may play basic roles in the larval gut. In addition, principal coordinate analysis (PCoA) of gut bacterial predicted gene ontologies revealed specialized features of the microbiotas associated with these mulberry pests, which were divided into two distinct clusters (macrolepidopterans vs. microlepidopterans). This pattern became even more prominent when more Lepidoptera species involved.<br><br>CONCLUSIONS: A suite of gut microbiota metabolic functions significantly correlated with larval size; the metabolism of terpenoids and polyketides, xenobiotics biodegradation and metabolism were specifically enriched in large species, while small larvae had enhanced nucleotide metabolism. Our report paves the way for uncovering the correlation between host phenotype and microbial symbiosis in this notorious insect pest group. This article is protected by copyright. All rights reserved.},
}
@article {pmid31602111,
year = {2019},
author = {Konwar, P and Vyas, N and Hossain, SS and Gore, MN and Choudhury, M},
title = {Nutritional Status of Adolescent Girls Belonging to the Tea Garden Estates of Sivasagar District, Assam, India.},
journal = {Indian journal of community medicine : official publication of Indian Association of Preventive &amp; Social Medicine},
volume = {44},
number = {3},
pages = {238-242},
doi = {10.4103/ijcm.IJCM_357_18},
pmid = {31602111},
issn = {0970-0218},
abstract = {Background: Any deficiency or inadequate dietary pattern can lead to poor nutrition which can further influence both growth and development throughout from infancy to adolescence. Since adolescents represent the next generation of parents, it is important to monitor their nutritional status at this crucial stage. Thus, this study aimed to explore the factors associated with nutritional status among adolescent girls belonging to these tea gardens.<br><br>Objective: The objective of this community-based cross-sectional study was to assess the nutritional status of adolescent girls belonging to the tea garden community and the association of the sociodemographic factors with it.<br><br>Materials and Methods: Anthropometric measurement was taken among adolescent girls in the tea estates of Nazira subdivision of Sivasagar district, Assam. The pattern of dietary intake among adolescents was also studied. The statistical analysis was done using SPSS version 15.<br><br>Results: The prevalence of thinness and stunting across 265 adolescent girls was 49.4% and 50.6%, respectively. Calorie and protein deficits were found to be 76.60% and 65%, respectively. Majority of the respondents, i.e., 66.80% of the participants, had a poor intake of essential food constituents. Moreover, 76.21% of the respondents were anemic. The association of different sociodemographic factors with thinness, inadequate protein intake, and anemia were found during the study.<br><br>Conclusion: Thinness and stunting along with protein-energy malnutrition and inadequate intake of important food groups were prevalent in adolescent tea community girls. Overall, the public health burden of malnutrition is still a persisting health problem in the tea gardens of Assam.},
}
@article {pmid31600926,
year = {2019},
author = {Marangoni, LFB and Mies, M and Güth, AZ and Banha, TNS and Inague, A and Fonseca, JDS and Dalmolin, C and Faria, SC and Ferrier-Pagès, C and Bianchini, A},
title = {Peroxynitrite Generation and Increased Heterotrophic Capacity Are Linked to the Disruption of the Coral-Dinoflagellate Symbiosis in a Scleractinian and Hydrocoral Species.},
journal = {Microorganisms},
volume = {7},
number = {10},
pages = {},
doi = {10.3390/microorganisms7100426},
pmid = {31600926},
issn = {2076-2607},
support = {23038.004300/2014-40//Coordenação de Aperfeiçoamento de Pessoal de Nível Superior/ ; 573949/2008-5//Conselho Nacional de Desenvolvimento Científico e Tecnológico/ ; 84/2010//Coordenação de Aperfeiçoamento de Pessoal de Nível Superior/ ; 104519-003//International Development Research Centre, IDRC, Ottawa, Canada/ ; },
abstract = {Ocean warming is one of the greatest global threats to coral reef ecosystems; it leads to the disruption of the coral-dinoflagellate symbiosis (bleaching) and to nutrient starvation, because corals mostly rely on autotrophy (i.e., the supply of photosynthates from the dinoflagellate symbionts) for their energy requirements. Although coral bleaching has been well studied, the early warning signs of bleaching, as well as the capacity of corals to shift from autotrophy to heterotrophy, are still under investigation. In this study, we evaluated the bleaching occurrence of the scleractinian coral Mussismillia harttii and the hydrocoral Millepora alcicornis during a natural thermal stress event, under the 2015-2016 El Niño influence in three reef sites of the South Atlantic. We focused on the link between peroxynitrite (ONOO-) generation and coral bleaching, as ONOO- has been very poorly investigated in corals and never during a natural bleaching event. We also investigated the natural trophic plasticity of the two corals through the use of new lipid biomarkers. The results obtained first demonstrate that ONOO- is linked to the onset and intensity of bleaching in both scleractinian corals and hydrocorals. Indeed, ONOO- concentrations were correlated with bleaching intensity, with the highest levels preceding the highest bleaching intensity. The time lag between bleaching and ONOO- peak was, however, species-specific. In addition, we observed that elevated temperatures forced heterotrophy in scleractinian corals, as Mu. harttii presented high heterotrophic activity 15 to 30 days prior bleaching occurrence. On the contrary, a lower heterotrophic activity was monitored for the hydrocoral Mi. alicornis, which also experienced higher bleaching levels compared to Mu. hartii. Overall, we showed that the levels of ONOO- in coral tissue, combined to the heterotrophic capacity, are two good proxies explaining the intensity of coral bleaching.},
}
@article {pmid31240798,
year = {2019},
author = {Greenler, SM and Estrada, LA and Kellner, KF and Saunders, MR and Swihart, RK},
title = {Prescribed fire and partial overstory removal alter an acorn-rodent conditional mutualism.},
journal = {Ecological applications : a publication of the Ecological Society of America},
volume = {29},
number = {7},
pages = {e01958},
doi = {10.1002/eap.1958},
pmid = {31240798},
issn = {1051-0761},
mesh = {Animals ; *Fires ; Forests ; *Quercus ; Rodentia ; Symbiosis ; },
abstract = {In eastern North America, oak (Quercus) regeneration failure has spurred management using silvicultural approaches better aligned with the autecology of oaks. In particular, shelterwood harvests can create favorable intermediate light conditions for oak establishment and prescribed fire is predicted (by the oak-fire hypothesis) to favor oak regeneration. These approaches substantially modify forest structure and may affect crucial trophic interactions including the conditional mutualism between oaks and granivorous rodents that scatterhoard acorns, which shifts along a continuum from antagonistic to mutualistic depending on external factors. We investigated how overwinter survival and dispersal of northern red oak (Quercus rubra) acorns were influenced by location within or outside of group shelterwood harvests (small canopy gaps created throughout an intact forest stand) with and without prescribed fire. We conducted two concurrent experiments to test (1) dispersal and survival of acorns presented on the forest floor and (2) acorn pilferage rates from caches that mimic squirrel scatterhoards in shelterwood gap/group interiors, edges, and the uncut forest matrix in burned and unburned forest stands. In both experiments, acorn survival was generally higher in burned than unburned stands. Acorn survival from forest floor presentations was higher in the unharvested forest matrix than harvest gap interiors; however, there was no effect of proximity to harvest gaps on survival of cached acorns. Survival of cached acorns was associated with understory vegetative cover (-), coarse woody debris cover (-), and distance to nearest tree (+), but uncorrelated with canopy cover above the cache. Our results suggest that reduced understory cover following prescribed fire may increase perceived habitat riskiness for granivores resulting in higher acorn survival up to 2 yr post-fire. These findings unify the oak-fire and oak-granivore conditional mutualism hypotheses, and suggest that the environmental conditions following prescribed fire and group shelterwood harvests may shift the oak-granivore conditional mutualism in a direction beneficial for oak regeneration.},
}
@article {pmid29849034,
year = {2018},
author = {Glasl, B and Smith, CE and Bourne, DG and Webster, NS},
title = {Exploring the diversity-stability paradigm using sponge microbial communities.},
journal = {Scientific reports},
volume = {8},
number = {1},
pages = {8425},
pmid = {29849034},
issn = {2045-2322},
mesh = {Animals ; *Biodiversity ; Host-Pathogen Interactions ; *Microbiota/genetics ; Pigmentation ; Porifera/metabolism/*microbiology/physiology ; RNA, Ribosomal, 16S/genetics ; Salinity ; Symbiosis ; },
abstract = {A key concept in theoretical ecology is the positive correlation between biodiversity and ecosystem stability. When applying this diversity-stability concept to host-associated microbiomes, the following questions emerge: (1) Does microbial diversity influence the stability of microbiomes upon environmental fluctuations? (2) Do hosts that harbor high versus low microbial diversity differ in their stress response? To test the diversity-stability concept in host-associated microbiomes, we exposed six marine sponge species with varying levels of microbial diversity to non-lethal salinity disturbances and followed their microbial composition over time using 16S rRNA gene amplicon sequencing. No signs of sponge stress were evident following salinity amendment and microbiomes exhibited compositional resistance irrespective of their microbial diversity. Compositional stability of the sponge microbiome manifests itself at distinct host taxonomic and host microbial diversity groups, with (1) stable host genotype-specific microbiomes at oligotype-level; (2) stable host species-specific microbiomes at genus-level; and (3) stable and specific microbiomes at phylum-level for hosts with high versus low microbial diversity. The resistance of sponge microbiomes together with the overall stability of sponge holobionts upon salinity fluctuations suggest that the stability-diversity concept does not appear to hold for sponge microbiomes and provides further evidence for the widely recognized environmental tolerance of sponges.},
}
@article {pmid31600710,
year = {2019},
author = {Zou, YN and Wu, HH and Giri, B and Wu, QS and Kuča, K},
title = {Mycorrhizal symbiosis down-regulates or does not change root aquaporin expression in trifoliate orange under drought stress.},
journal = {Plant physiology and biochemistry : PPB},
volume = {144},
number = {},
pages = {292-299},
doi = {10.1016/j.plaphy.2019.10.001},
pmid = {31600710},
issn = {1873-2690},
abstract = {Arbuscular mycorrhizas absorb water from soil to host plants, while the relationship between mycorrhizas and aquaporins (AQPs, membrane water channel proteins, which function in water transport) in mycorrhizal plants is unclear. In this study, Funneliformis mosseae-colonized trifoliate orange (Poncirus trifoliata) seedlings were grown in pots fitted with 37-μm nylon meshes at the bottom of each pot to allow mycorrhizal hyphae absorb water from an outer beaker. The expression of seven plasma membrane intrinsic proteins (PIPs) genes, six tonoplast intrinsic proteins (TIPs) genes, and four nodulin-26 like intrinsic proteins (NIPs) genes were analyzed in roots of both well-watered (WW) and drought stressed (DS) plants. The six-week DS plants dramatically increased hyphal water absorption rate by 1.4 times, as compared with WW plants. Mycorrhizal plants exhibited greater plant growth performance, leaf water status (water potential and relative water content), and gas exchange under both WW and DS conditions. Mycorrhizal inoculation induced diverse expression patterns in these AQPs under WW: up-regulation of PtNIP1;1, PtPIP2;1, and PtPIP2;5, down-regulation of PtNIP1;2, PtNIP6;1, PtPIP1;2, PtPIP1;5, PtPIP2;8, PtTIP1;1, PtTIP1;2, PtTIP1;3, and PtTIP5;1, and no changes in other AQPs. However, the expression of PtPIPs and PtNIPs was down-regulated by mycorrhizal inoculation under DS, and PtTIPs was not induced by mycorrhizal colonization under DS. The expression pattern of AQPs in response to mycorrhizas under DS is a way of mycorrhizal plants to minimize water loss.},
}
@article {pmid31600251,
year = {2019},
author = {Chabaud, M and Fournier, J and Brichet, L and Abdou-Pavy, I and Imanishi, L and Brottier, L and Pirolles, E and Hocher, V and Franche, C and Bogusz, D and Wall, LG and Svistoonoff, S and Gherbi, H and Barker, DG},
title = {Chitotetraose activates the fungal-dependent endosymbiotic signaling pathway in actinorhizal plant species.},
journal = {PloS one},
volume = {14},
number = {10},
pages = {e0223149},
doi = {10.1371/journal.pone.0223149},
pmid = {31600251},
issn = {1932-6203},
abstract = {Mutualistic plant-microbe associations are widespread in natural ecosystems and have made major contributions throughout the evolutionary history of terrestrial plants. Amongst the most remarkable of these are the so-called root endosymbioses, resulting from the intracellular colonization of host tissues by either arbuscular mycorrhizal (AM) fungi or nitrogen-fixing bacteria that both provide key nutrients to the host in exchange for energy-rich photosynthates. Actinorhizal host plants, members of the Eurosid 1 clade, are able to associate with both AM fungi and nitrogen-fixing actinomycetes known as Frankia. Currently, little is known about the molecular signaling that allows these plants to recognize their fungal and bacterial partners. In this article, we describe the use of an in vivo Ca2+ reporter to identify symbiotic signaling responses to AM fungi in roots of both Casuarina glauca and Discaria trinervis, actinorhizal species with contrasting modes of Frankia colonization. This approach has revealed that, for both actinorhizal hosts, the short-chain chitin oligomer chitotetraose is able to mimic AM fungal exudates in activating the conserved symbiosis signaling pathway (CSSP) in epidermal root cells targeted by AM fungi. These results mirror findings in other AM host plants including legumes and the monocot rice. In addition, we show that chitotetraose is a more efficient elicitor of CSSP activation compared to AM fungal lipo-chitooligosaccharides. These findings reinforce the likely role of short-chain chitin oligomers during the initial stages of the AM association, and are discussed in relation to both our current knowledge about molecular signaling during Frankia recognition as well as the different microsymbiont root colonization mechanisms employed by actinorhizal hosts.},
}
@article {pmid31600190,
year = {2019},
author = {Becking, T and Chebbi, MA and Giraud, I and Moumen, B and Laverré, T and Caubet, Y and Peccoud, J and Gilbert, C and Cordaux, R},
title = {Sex chromosomes control vertical transmission of feminizing Wolbachia symbionts in an isopod.},
journal = {PLoS biology},
volume = {17},
number = {10},
pages = {e3000438},
doi = {10.1371/journal.pbio.3000438},
pmid = {31600190},
issn = {1545-7885},
abstract = {Microbial endosymbiosis is widespread in animals, with major ecological and evolutionary implications. Successful symbiosis relies on efficient vertical transmission through host generations. However, when symbionts negatively affect host fitness, hosts are expected to evolve suppression of symbiont effects or transmission. Here, we show that sex chromosomes control vertical transmission of feminizing Wolbachia endosymbionts in the isopod Armadillidium nasatum. Theory predicts that the invasion of an XY/XX species by cytoplasmic sex ratio distorters is unlikely because it leads to fixation of the unusual (and often lethal or infertile) YY genotype. We demonstrate that A. nasatum X and Y sex chromosomes are genetically highly similar and that YY individuals are viable and fertile, thereby enabling Wolbachia spread in this XY-XX species. Nevertheless, we show that Wolbachia cannot drive fixation of YY individuals, because infected YY females do not transmit Wolbachia to their offspring, unlike XX and XY females. The genetic basis fits the model of a Y-linked recessive allele (associated with an X-linked dominant allele), in which the homozygous state suppresses Wolbachia transmission. Moreover, production of all-male progenies by infected YY females restores a balanced sex ratio at the host population level. This suggests that blocking of Wolbachia transmission by YY females may have evolved to suppress feminization, thereby offering a whole new perspective on the evolutionary interplay between microbial symbionts and host sex chromosomes.},
}
@article {pmid31598235,
year = {2019},
author = {Jono, T and Kojima, Y and Mizuno, T},
title = {Novel cooperative antipredator tactics of an ant specialized against a snake.},
journal = {Royal Society open science},
volume = {6},
number = {8},
pages = {190283},
doi = {10.1098/rsos.190283},
pmid = {31598235},
issn = {2054-5703},
abstract = {Eusocial insects can express surprisingly complex cooperative defence of the colony. Brood and reproductive castes typically remain in the nest and are protected by workers' various antipredator tactics against intruders. In Madagascar, a myrmicine ant, Aphaenogaster swammerdami, occurs sympatrically with a large blindsnake, Madatyphlops decorsei. As blindsnakes generally specialize on feeding on termites and ants brood by intruding into the nest, these snakes are presumably a serious predator on the ant. Conversely, a lamprophiid snake, Madagascarophis colubrinus, is considered to occur often in active A. swammerdami nests without being attacked. By presenting M. colubrinus, M. decorsei and a control snake, Thamnosophis lateralis, at the entrance of the nest, we observed two highly specialized interactions between ants and snakes: the acceptance of M. colubrinus into the nest and the cooperative evacuation of the brood from the nest for protection against the ant-eating M. decorsei. Given that M. colubrinus is one of the few known predators of blindsnakes in this area, A. swammerdami may protect their colonies against this blindsnake by two antipredator tactics, symbiosis with M. colubrinus and evacuation in response to intrusion by blindsnakes. These findings demonstrate that specialized predators can drive evolution of complex cooperative defence in eusocial species.},
}
@article {pmid31597890,
year = {2019},
author = {Hashimoto, S and Wongdee, J and Songwattana, P and Greetatorn, T and Goto, K and Tittabutr, P and Boonkerd, N and Teaumroong, N and Uchiumi, T},
title = {Homocitrate Synthase Genes of Two Wide-Host-Range Bradyrhizobium Strains are Differently Required for Symbiosis Depending on Host Plants.},
journal = {Microbes and environments},
volume = {},
number = {},
pages = {},
doi = {10.1264/jsme2.ME19078},
pmid = {31597890},
issn = {1347-4405},
abstract = {The nifV gene encodes homocitrate synthase, the enzyme that catalyzes the formation of homocitrate, which is essential for arranging the FeMo-cofactor in the catalytic center of nitrogenase. Some host plants, such as Lotus japonicus, supply homocitrate to their symbionts, in this case, Mesorhizobium loti, which lacks nifV. In contrast, Bradyrhizobium ORS285, a symbiont of Aeschynomene cross-inoculation (CI) groups 2 and 3, requires nifV for symbiosis with Aeschynomene species that belong to CI group 3, and some species belonging to CI group 2. However, it currently remains unclear whether rhizobial nifV is required for symbiosis with Aeschynomene species belonging to CI group 1 or with other legumes. We generated nifV-disruption (ΔnifV) mutants of two wide-host-range rhizobia, Bradyrhizobium SUTN9-2 and DOA9, to investigate whether they require nifV for symbiosis. Both ΔnifV mutant strains showed significantly less nitrogenase activity in a free-living state than the respective wild-type strains. The symbiotic phenotypes of SUTN9-2, DOA9, and their ΔnifV mutants were examined with four legumes, Aeschynomene americana, Stylosanthes hamata, Indigofera tinctoria, and Desmodium tortuosum. nifV was required for the efficient symbiosis of SUTN9-2 with A. americana (CI group 1), but not for that of DOA9. SUTN9-2 established symbiosis with all three other legumes; nifV was required for symbiosis with I. tinctoria and D. tortuosum. These results suggest that, in addition to Aeschynomene CI groups 2 and 3, CI group 1 and several other legumes require the rhizobial nifV for symbiosis.},
}
@article {pmid31597352,
year = {2019},
author = {Torres, N and Hilbert, G and Antolín, MC and Goicoechea, N},
title = {Aminoacids and Flavonoids Profiling in Tempranillo Berries Can Be Modulated by the Arbuscular Mycorrhizal Fungi.},
journal = {Plants (Basel, Switzerland)},
volume = {8},
number = {10},
pages = {},
doi = {10.3390/plants8100400},
pmid = {31597352},
issn = {2223-7747},
support = {AGL2014-56075-C2-1-R//SPANISH MINISTRY OF ECONOMY AND COMPETENCY/ ; INNOVINE 311775//INNOVINE European project/ ; FPU Grant//SPANISH MINISTRY OF EDUCATION, CULTURE AND SPORT/ ; },
abstract = {(1) Background: Vitisvinifera L. cv. Tempranillo is cultivated over the world for its wine of high quality. The association of Tempranillo with arbuscular mycorrhizal fungi (AMF) induced the accumulation of phenolics and carotenoids in leaves, affected the metabolism of abscisic acid (ABA) during berry ripening, and modulated some characteristics and quality aspects of grapes. The objective of this study was to elucidate if AMF influenced the profiles and the content of primary and secondary metabolites determinants for berry quality in Tempranillo. (2) Methods: Fruit-bearing cuttings inoculated with AMF or uninoculated were cultivated under controlled conditions. (3) Results: Mycorrhizal symbiosis modified the profile of metabolites in Tempranillo berries, especially those of the primary compounds. The levels of glucose and amino acids clearly increased in berries of mycorrhized Tempranillo grapevines, including those of the aromatic precursor amino acids. However, mycorrhizal inoculation barely influenced the total amount and the profiles of anthocyanins and flavonols in berries. (4) Conclusions: Mycorrhizal inoculation of Tempranillo grapevines may be an alternative to the exogenous application of nitrogen compounds in order to enhance the contents of amino acids in grapes, which may affect the aromatic characteristics of wines.},
}
@article {pmid30444650,
year = {2018},
author = {O'Brien, AM and Sawers, RJH and Ross-Ibarra, J and Strauss, SY},
title = {Evolutionary Responses to Conditionality in Species Interactions across Environmental Gradients.},
journal = {The American naturalist},
volume = {192},
number = {6},
pages = {715-730},
doi = {10.1086/700118},
pmid = {30444650},
issn = {1537-5323},
mesh = {Adaptation, Physiological ; *Biological Coevolution ; Biological Evolution ; Computer Simulation ; Ecosystem ; Geography ; Models, Genetic ; Mutation ; *Symbiosis ; },
abstract = {The outcomes of many species interactions are conditional on the environments in which they occur. Often, interactions grade from being more positive under stressful or low-resource conditions to more antagonistic or neutral under benign conditions. Here, we take predictions about two well-supported ecological theories on conditionality-limiting resource models and the stress-gradient hypothesis-and combine them with those from the geographic mosaic theory of coevolution (GMTC) to generate predictions for systematic patterns of adaptation and coadaptation between partners along abiotic gradients. When interactions become more positive in stressful environments, mutations that increase fitness in one partner may also increase fitness in the other; because fitnesses are aligned, selection should favor greater mutualistic adaptation and coadaptation between interacting species in stressful ends of environmental gradients. As a corollary, in benign environments antagonistic coadaptation could result in Red Queen or arms-race dynamics or the reduction of antagonism through character displacement and niche partitioning. Here, we distinguish between generally mutualistic or antagonistic adaptation (i.e., mutations in one partner that have similar effects across multiple populations of the other) and specific adaptations to sympatric partners (local adaptation), which can occur either alone or simultaneously. We then outline the kinds of data required to test these predictions, develop experimental designs and statistical methods, and demonstrate these using simulations based on GMTC models. Our methods can be applied to a range of conditional outcomes and may also be useful in assisted translocation approaches in the face of climate change.},
}
@article {pmid30054358,
year = {2018},
author = {Qin, S and Feng, WW and Zhang, YJ and Wang, TT and Xiong, YW and Xing, K},
title = {Diversity of Bacterial Microbiota of Coastal Halophyte Limonium sinense and Amelioration of Salinity Stress Damage by Symbiotic Plant Growth-Promoting Actinobacterium Glutamicibacter halophytocola KLBMP 5180.},
journal = {Applied and environmental microbiology},
volume = {84},
number = {19},
pages = {},
pmid = {30054358},
issn = {1098-5336},
mesh = {Actinobacteria/genetics/*physiology ; Bacteria/classification/genetics/*isolation &amp; purification ; China ; Endophytes/genetics/physiology ; Microbiota ; Phylogeny ; Plant Leaves/growth &amp; development/metabolism/microbiology ; Plumbaginaceae/growth &amp; development/metabolism/*microbiology ; Salt Stress ; Salt-Tolerant Plants/growth &amp; development/metabolism/*microbiology ; Sodium Chloride/metabolism ; *Symbiosis ; },
abstract = {Plant-associated microorganisms are considered a key determinant of plant health and growth. However, little information is available regarding the composition and ecological function of the roots' and leaves' bacterial microbiota of halophytes. Here, using both culture-dependent and culture-independent techniques, we characterized the bacterial communities of the roots and leaves as well as the rhizosphere and bulk soils of the coastal halophyte Limonium sinense in Jiangsu Province, China. We identified 49 representative bacterial strains belonging to 17 genera across all samples, with Glutamicibacter as the most dominant genus. All Glutamicibacter isolates showed multiple potential plant growth promotion traits and tolerated a high concentration of NaCl and a wide pH range. Interestingly, further inoculation experiments showed that the Glutamicibacter halophytocola strain KLBMP 5180 isolated from root tissue significantly promoted host growth under NaCl stress. Indeed, KLBMP 5180 inoculation increased the concentrations of total chlorophyll, proline, antioxidative enzymes, flavonoids, K+, and Ca2+ in the leaves; the concentrations of malondialdehyde (MDA) and Na+ were reduced. A transcriptome analysis identified 1,359 and 328 differentially expressed genes (DEGs) in inoculated seedlings treated with 0 and 250 mM NaCl, respectively. We found that pathways related to phenylpropanoid and flavonoid biosynthesis and ion transport and metabolism might play more important roles in host salt stress tolerance induced by KLBMP 5180 inoculation compared to that in noninoculated leaves. Our results provide novel insights into the complex composition and function of the bacterial microbiota of the coastal halophyte L. sinense and suggest that halophytes might recruit specific bacteria to enhance their tolerance of harsh environments.IMPORTANCE Halophytes are important coastal plants often used for the remediation of saline coastal soils. Limonium sinense is well known for its medical properties and phytoremediation of saline soils. However, excessive exploitation and utilization have made the wild resource endangered. The use of endophytic and rhizosphere bacteria may be one of the suitable ways to solve the problem. This study was undertaken to develop approaches to improve the growth of L. sinense using endophytes. The application of actinobacterial endophytes ameliorated salt stress damage of the host via complex physiological and molecular mechanisms. The results also highlight the potential of using habitat-adapted, symbiotic, indigenous endophytic bacteria to enhance the growth and ameliorate abiotic stress damage of host plants growing in special habitats.},
}
@article {pmid31596956,
year = {2019},
author = {Zeng, T and Rodriguez-Moreno, L and Mansurkhodzaev, A and Wang, P and van den Berg, W and Gasciolli, V and Cottaz, S and Fort, S and Thomma, BPHJ and Bono, JJ and Bisseling, T and Limpens, E},
title = {A LysM effector subverts chitin-triggered immunity to facilitate arbuscular mycorrhizal symbiosis.},
journal = {The New phytologist},
volume = {},
number = {},
pages = {},
doi = {10.1111/nph.16245},
pmid = {31596956},
issn = {1469-8137},
abstract = {Arbuscular mycorrhizal (AM) fungi greatly improve mineral uptake by host plants in nutrient-depleted soil and can intracellularly colonize root cortex cells in the vast majority of higher plants. However, AM fungi possess common fungal cell wall components such as chitin which can be recognized by plant chitin receptors to trigger immune responses, raising the question how AM fungi effectively evade chitin-triggered immune responses during symbiosis. In this study, we characterize a secreted LysM (Lysin motif) effector identified from the model AM fungal species Rhizophagus irregularis, called RiSLM. RiSLM is one of the highest expressed effector proteins in intraradical mycelium during the symbiosis. In vitro binding assays show that RiSLM binds chitin-oligosaccharides and can protect fungal cell walls from chitinases. Moreover, RiSLM efficiently interferes with chitin-triggered immune responses, such as defence gene induction and reactive oxygen species production in Medicago truncatula. Although RiSLM also binds to symbiotic (lipo-)chitooligosaccharides it does not interfere significantly with symbiotic signalling in Medicago. Host-induced gene silencing of RiSLM greatly reduces fungal colonization levels. Taken together, our results reveal a key role for AM fungal LysM effectors to subvert chitin-triggered immunity in symbiosis, pointing to a common role for LysM effectors in both symbiotic and pathogenic fungi.},
}
@article {pmid31596856,
year = {2019},
author = {Payelleville, A and Blackburn, D and Lanois, A and Pagès, S and Cambon, MC and Ginibre, N and Clarke, DJ and Givaudan, A and Brillard, J},
title = {Role of the Photorhabdus Dam methyltransferase during interactions with its invertebrate hosts.},
journal = {PloS one},
volume = {14},
number = {10},
pages = {e0212655},
doi = {10.1371/journal.pone.0212655},
pmid = {31596856},
issn = {1932-6203},
abstract = {Photorhabdus luminescens is an entomopathogenic bacterium found in symbiosis with the nematode Heterorhabditis. Dam DNA methylation is involved in the pathogenicity of many bacteria, including P. luminescens, whereas studies about the role of bacterial DNA methylation during symbiosis are scarce. The aim of this study was to determine the role of Dam DNA methylation in P. luminescens during the whole bacterial life cycle including during symbiosis with H. bacteriophora. We constructed a strain overexpressing dam by inserting an additional copy of the dam gene under the control of a constitutive promoter in the chromosome of P. luminescens and then achieved association between this recombinant strain and nematodes. The dam overexpressing strain was able to feed the nematode in vitro and in vivo similarly as a control strain, and to re-associate with Infective Juvenile (IJ) stages in the insect. No difference in the amount of emerging IJs from the cadaver was observed between the two strains. Compared to the nematode in symbiosis with the control strain, a significant increase in LT50 was observed during insect infestation with the nematode associated with the dam overexpressing strain. These results suggest that during the life cycle of P. luminescens, Dam is not involved the bacterial symbiosis with the nematode H. bacteriophora, but it contributes to the pathogenicity of the nemato-bacterial complex.},
}
@article {pmid31595476,
year = {2020},
author = {Tak, N and Bissa, G and Gehlot, HS},
title = {Methods for Isolation and Characterization of Nitrogen-Fixing Legume-Nodulating Bacteria.},
journal = {Methods in molecular biology (Clifton, N.J.)},
volume = {2057},
number = {},
pages = {119-143},
doi = {10.1007/978-1-4939-9790-9_12},
pmid = {31595476},
issn = {1940-6029},
abstract = {Symbiotic nitrogen fixation (SNF) is a characteristic feature of nodulating legumes. The wild legumes are comparatively less explored for their SNF ability; hence, it is essential to study nodulation and identify the microsymbiont diversity associated with them. This chapter aims to describe the methodology for nodule hunting; trapping, isolation, and characterization of root nodule bacteria (RNB) at phenotypic, genotypic, and symbiotic levels. The documentation of nodulating native legume species and the rhizobial diversity associated with them in various parts of world has gained attention as this symbiotic association provides fixed nitrogen, improves productivity of plants in an ecofriendly manner. Before field-based applications the symbiotic bacteria need to be assessed for their N fixing ability as well as characterized at molecular level. The phylogeny based on symbiosis-essential genes supplemented with the host-range studies helps in better understanding of the symbiotaxonomy of rhizobia. More efficient symbiotic couples need to be screened by cross-nodulation studies for their application in agricultural practices.},
}
@article {pmid31595051,
year = {2019},
author = {Yang, Y and Sun, J and Sun, Y and Kwan, YH and Wong, WC and Zhang, Y and Xu, T and Feng, D and Zhang, Y and Qiu, JW and Qian, PY},
title = {Genomic, transcriptomic, and proteomic insights into the symbiosis of deep-sea tubeworm holobionts.},
journal = {The ISME journal},
volume = {},
number = {},
pages = {},
doi = {10.1038/s41396-019-0520-y},
pmid = {31595051},
issn = {1751-7370},
support = {DY135-E2-1-03//China Ocean Mineral Resources Research and Development Association (China Ocean Mineral Resources R&amp;D Association)/ ; },
abstract = {Deep-sea hydrothermal vents and methane seeps are often densely populated by animals that host chemosynthetic symbiotic bacteria, but the molecular mechanisms of such host-symbiont relationship remain largely unclear. We characterized the symbiont genome of the seep-living siboglinid Paraescarpia echinospica and compared seven siboglinid-symbiont genomes. Our comparative analyses indicate that seep-living siboglinid endosymbionts have more virulence traits for establishing infections and modulating host-bacterium interaction than the vent-dwelling species, and have a high potential to resist environmental hazards. Metatranscriptome and metaproteome analyses of the Paraescarpia holobiont reveal that the symbiont is highly versatile in its energy use and efficient in carbon fixation. There is close cooperation within the holobiont in production and supply of nutrients, and the symbiont may be able to obtain nutrients from host cells using virulence factors. Moreover, the symbiont is speculated to have evolved strategies to mediate host protective immunity, resulting in weak expression of host innate immunity genes in the trophosome. Overall, our results reveal the interdependence of the tubeworm holobiont through mutual nutrient supply, a pathogen-type regulatory mechanism, and host-symbiont cooperation in energy utilization and nutrient production, which is a key adaptation allowing the tubeworm to thrive in deep-sea chemosynthetic environments.},
}
@article {pmid31594815,
year = {2019},
author = {Thiergart, T and Zgadzaj, R and Bozsóki, Z and Garrido-Oter, R and Radutoiu, S and Schulze-Lefert, P},
title = {Lotus japonicus Symbiosis Genes Impact Microbial Interactions between Symbionts and Multikingdom Commensal Communities.},
journal = {mBio},
volume = {10},
number = {5},
pages = {},
doi = {10.1128/mBio.01833-19},
pmid = {31594815},
issn = {2150-7511},
abstract = {The wild legume Lotus japonicus engages in mutualistic symbiotic relationships with arbuscular mycorrhiza (AM) fungi and nitrogen-fixing rhizobia. Using plants grown in natural soil and community profiling of bacterial 16S rRNA genes and fungal internal transcribed spacers (ITSs), we examined the role of the Lotus symbiosis genes RAM1, NFR5, SYMRK, and CCaMK in structuring bacterial and fungal root-associated communities. We found host genotype-dependent community shifts in the root and rhizosphere compartments that were mainly confined to bacteria in nfr5 or fungi in ram1 mutants, while symrk and ccamk plants displayed major changes across both microbial kingdoms. We observed in all AM mutant roots an almost complete depletion of a large number of Glomeromycota taxa that was accompanied by a concomitant enrichment of Helotiales and Nectriaceae fungi, suggesting compensatory niche replacement within the fungal community. A subset of Glomeromycota whose colonization is strictly dependent on the common symbiosis pathway was retained in ram1 mutants, indicating that RAM1 is dispensable for intraradical colonization by some Glomeromycota fungi. However, intraradical colonization by bacteria belonging to the Burkholderiaceae and Anaeroplasmataceae is dependent on AM root infection, revealing a microbial interkingdom interaction. Despite the overall robustness of the bacterial root microbiota against major changes in the composition of root-associated fungal assemblages, bacterial and fungal cooccurrence network analysis demonstrates that simultaneous disruption of AM and rhizobium symbiosis increases the connectivity among taxa of the bacterial root microbiota. Our findings imply a broad role for Lotus symbiosis genes in structuring the root microbiota and identify unexpected microbial interkingdom interactions between root symbionts and commensal communities.IMPORTANCE Studies on symbiosis genes in plants typically focus on binary interactions between roots and soilborne nitrogen-fixing rhizobia or mycorrhizal fungi in laboratory environments. We utilized wild type and symbiosis mutants of a model legume, grown in natural soil, in which bacterial, fungal, or both symbioses are impaired to examine potential interactions between the symbionts and commensal microorganisms of the root microbiota when grown in natural soil. This revealed microbial interkingdom interactions between the root symbionts and fungal as well as bacterial commensal communities. Nevertheless, the bacterial root microbiota remains largely robust when fungal symbiosis is impaired. Our work implies a broad role for host symbiosis genes in structuring the root microbiota of legumes.},
}
@article {pmid31593868,
year = {2019},
author = {Bongrand, C and Ruby, EG},
title = {The impact of Vibrio fischeri strain variation on host colonization.},
journal = {Current opinion in microbiology},
volume = {50},
number = {},
pages = {15-19},
doi = {10.1016/j.mib.2019.09.002},
pmid = {31593868},
issn = {1879-0364},
abstract = {Strain-level epidemiology is a key approach to understanding the mechanisms underlying establishment of any host-microbe association. The squid-vibrio light organ symbiosis has proven to be an informative and tractable experimental model in which to discover these mechanisms because it involves only one bacterial species, Vibrio fischeri. In this horizontally transmitted symbiosis, the squid presents nutrients to the bacteria located in a bilobed light-emitting organ, while the symbionts provide bioluminescence to their host. To initiate this association, V. fischeri cells go through several distinct stages: from free-living in the bacterioplankton, to forming a multicellular aggregation near pores on the light organ's surface, to migrating through the pores and into crypts deep in the light organ, where the symbiont population grows and luminesces. Because individual cells must successfully navigate these distinct regions, phenotypic differences between strains will have a strong impact on the composition of the population finally colonizing the squid. Here we review recent advances in our understanding of behavioral characteristics that differentially drive a strain's success, including its effectiveness of aggregation, the rapidity with which it reaches the deep crypts, and its deployment of type VI secretion.},
}
@article {pmid31592190,
year = {2019},
author = {Reynolds, LA and Hornett, EA and Jiggins, CD and Hurst, GDD},
title = {Suppression of Wolbachia-mediated male-killing in the butterfly Hypolimnas bolina involves a single genomic region.},
journal = {PeerJ},
volume = {7},
number = {},
pages = {e7677},
doi = {10.7717/peerj.7677},
pmid = {31592190},
issn = {2167-8359},
abstract = {Background: Sex ratio distorting agents (maternally inherited symbionts and meiotically-driving sex chromosomes) are common in insects. When these agents rise to high frequencies they create strong population sex ratio bias and selection then favours mutations that act to restore the rare sex. Despite this strong selection pressure, the evolution of mutations that suppress sex ratio distorting elements appears to be constrained in many cases, where sex-biased populations persist for many generations. This scenario has been observed in the butterfly Hypolimnas bolina, where Wolbachia-mediated male killing endured for 800-1,000 generations across multiple populations before the evolution of suppression. Here we test the hypothesis that this evolutionary lag is the result of suppression being a multilocus trait requiring multiple mutations.<br><br>Methods: We developed genetic markers, based on conservation of synteny, for each H. bolina chromosome and verified coverage using recombinational mapping. We then used a Wolbachia-infected mapping family to assess each chromosome for the presence of loci required for male survival, as determined by the presence of markers in all surviving sons.<br><br>Results: Informative markers were obtained for each of the 31 chromosomes in H. bolina. The only marker that cosegregated with suppression was located on chromosome 25. A genomic region necessary for suppression has previously been located on this chromosome. We therefore conclude that a single genomic region of the H. bolina genome is necessary for male-killing suppression.<br><br>Discussion: The evolutionary lag observed in our system is not caused by a need for changes at multiple genomic locations. The findings favour hypotheses in which either multiple mutations are required within a single genomic region, or the suppressor mutation is a singularly rare event.},
}
@article {pmid31591568,
year = {2019},
author = {Ichikawa, T and Hirahara, K and Kokubo, K and Kiuchi, M and Aoki, A and Morimoto, Y and Kumagai, J and Onodera, A and Mato, N and Tumes, DJ and Goto, Y and Hagiwara, K and Inagaki, Y and Sparwasser, T and Tobe, K and Nakayama, T},
title = {CD103hi Treg cells constrain lung fibrosis induced by CD103lo tissue-resident pathogenic CD4 T cells.},
journal = {Nature immunology},
volume = {},
number = {},
pages = {},
doi = {10.1038/s41590-019-0494-y},
pmid = {31591568},
issn = {1529-2916},
support = {JP19gm1210003//Japan Agency for Medical Research and Development (AMED)/ ; JP19ek0410060//Japan Agency for Medical Research and Development (AMED)/ ; JP19gm6110005//Japan Agency for Medical Research and Development (AMED)/ ; JP19ek0410045//Japan Agency for Medical Research and Development (AMED)/ ; (S) 26221305//Ministry of Education, Culture, Sports, Science and Technology (MEXT)/ ; JP19H05650//Ministry of Education, Culture, Sports, Science and Technology (MEXT)/ ; (C) 19K16683//Ministry of Education, Culture, Sports, Science and Technology (MEXT)/ ; (C) 18K07164//Ministry of Education, Culture, Sports, Science and Technology (MEXT)/ ; },
abstract = {Tissue-resident memory T cells (TRM cells) are crucial mediators of adaptive immunity in nonlymphoid tissues. However, the functional heterogeneity and pathogenic roles of CD4+ TRM cells that reside within chronic inflammatory lesions remain unknown. We found that CD69hiCD103lo CD4+ TRM cells produced effector cytokines and promoted the inflammation and fibrotic responses induced by chronic exposure to Aspergillus fumigatus. Simultaneously, immunosuppressive CD69hiCD103hiFoxp3+ CD4+ regulatory T cells were induced and constrained the ability of pathogenic CD103lo TRM cells to cause fibrosis. Thus, lung tissue-resident CD4+ T cells play crucial roles in the pathology of chronic lung inflammation, and CD103 expression defines pathogenic effector and immunosuppressive tissue-resident cell subpopulations in the inflamed lung.},
}
@article {pmid31591240,
year = {2019},
author = {Teulet, A and Busset, N and Fardoux, J and Gully, D and Chaintreuil, C and Cartieaux, F and Jauneau, A and Comorge, V and Okazaki, S and Kaneko, T and Gressent, F and Nouwen, N and Arrighi, JF and Koebnik, R and Mergaert, P and Deslandes, L and Giraud, E},
title = {The rhizobial type III effector ErnA confers the ability to form nodules in legumes.},
journal = {Proceedings of the National Academy of Sciences of the United States of America},
volume = {},
number = {},
pages = {},
doi = {10.1073/pnas.1904456116},
pmid = {31591240},
issn = {1091-6490},
abstract = {Several Bradyrhizobium species nodulate the leguminous plant Aeschynomene indica in a type III secretion system-dependent manner, independently of Nod factors. To date, the underlying molecular determinants involved in this symbiotic process remain unknown. To identify the rhizobial effectors involved in nodulation, we mutated 23 out of the 27 effector genes predicted in Bradyrhizobium strain ORS3257. The mutation of nopAO increased nodulation and nitrogenase activity, whereas mutation of 5 other effector genes led to various symbiotic defects. The nopM1 and nopP1 mutants induced a reduced number of nodules, some of which displayed large necrotic zones. The nopT and nopAB mutants induced uninfected nodules, and a mutant in a yet-undescribed effector gene lost the capacity for nodule formation. This effector gene, widely conserved among bradyrhizobia, was named ernA for &quot;effector required for nodulation-A.&quot; Remarkably, expressing ernA in a strain unable to nodulate A. indica conferred nodulation ability. Upon its delivery by Pseudomonas fluorescens into plant cells, ErnA was specifically targeted to the nucleus, and a fluorescence resonance energy transfer-fluorescence lifetime imaging microscopy approach supports the possibility that ErnA binds nucleic acids in the plant nuclei. Ectopic expression of ernA in A. indica roots activated organogenesis of root- and nodule-like structures. Collectively, this study unravels the symbiotic functions of rhizobial type III effectors playing distinct and complementary roles in suppression of host immune functions, infection, and nodule organogenesis, and suggests that ErnA triggers organ development in plants by a mechanism that remains to be elucidated.},
}
@article {pmid31591150,
year = {2019},
author = {Deng, J and Zhu, F and Liu, J and Zhao, Y and Wen, J and Wang, T and Dong, J},
title = {Transcription factor bHLH2 represses CYSTEINE PROTEASE 77 to negatively regulate nodule senescence.},
journal = {Plant physiology},
volume = {},
number = {},
pages = {},
doi = {10.1104/pp.19.00574},
pmid = {31591150},
issn = {1532-2548},
abstract = {Legume-rhizobia symbiosis is a time-limited process due to the onset of senescence, which results in the degradation of host plant cells and symbiosomes. A number of transcription factors, proteases, and functional genes have been associated with nodule senescence; however, whether other proteases or transcription factors are involved in nodule senescence remains poorly understood. In this study, we identified an early nodule senescence mutant in Medicago truncatula, denoted bhlh2 (basic helix-loop-helix transcription factor 2), that exhibits decreased nitrogenase activity, acceleration of plant programmed cell death (PCD), and accumulation of reactive oxygen species (ROS). The results suggest that MtbHLH2 plays a negative role in nodule senescence. Nodules of wild-type and bhlh2-TALEN mutant plants at 28 days post inoculation were used for transcriptome sequencing. The transcriptome data analysis identified a papain-like cysteine protease gene, denoted MtCP77, that could serve as a potential target of MtbHLH2. Electrophoretic mobility shift assays and chromatin immunoprecipitation analysis demonstrated that MtbHLH2 directly binds to the promoter of MtCP77 to inhibit its expression. MtCP77 positively regulates nodule senescence by accelerating plant PCD and ROS accumulation. In addition, the expression of MtbHLH2 in the nodules gradually decreased from the meristematic zone to the nitrogen fixation zone, whereas the expression of MtCP77 showed enhancement. These results indicate that MtbHLH2 and MtCP77 have opposite functions in the regulation of nodule senescence. These results reveal significant roles for MtbHLH2 and MtCP77 in plant PCD, ROS accumulation, and nodule senescence, and improve our understanding of the regulation of the nodule senescence process.},
}
@article {pmid31591000,
year = {2019},
author = {Msaddak, A and Rejili, M and Durán, D and Mars, M and Palacios, JM and Ruiz-Argüeso, T and Rey, L and Imperial, J},
title = {Microvirga tunisiensis sp. nov., a root nodule symbiotic bacterium isolated from Lupinus micranthus and L. luteus grown in Northern Tunisia.},
journal = {Systematic and applied microbiology},
volume = {},
number = {},
pages = {126015},
doi = {10.1016/j.syapm.2019.126015},
pmid = {31591000},
issn = {1618-0984},
abstract = {Three bacterial strains, LmiM8T, LmiE10 and LluTb3, isolated from nitrogen-fixing nodules of Lupinus micranthus (Lmi strains) and L. luteus (Llu strain) growing in Northern Tunisia were analysed using genetic, phenotypic and symbiotic approaches. Phylogenetic analyses based on rrs and concatenated gyrB and dnaK genes suggested that these Lupinus strains constitute a new Microvirga species with identities ranging from 95 to 83% to its closest relatives Microvirga makkahensis, M. vignae, M. zambiensis, M. ossetica, and M. lotononidis. The genome sequences of strains LmiM8T and LmiE10 exhibited pairwise Average Nucleotide Identities (ANIb) above 99.5%, significantly distant (73-89% pairwise ANIb) from other Microvirga species sequenced (M. zambiensis and M. ossetica). A phylogenetic analysis based on the symbiosis-related gene nodA placed the sequences of the new species in a divergent clade close to Mesorhizobium, Microvirga and Bradyrhizobium strains, suggesting that the M. tunisiensis strains represent a new symbiovar different from the Bradyrhizobium symbiovars defined to date. In contrast, the phylogeny derived from another symbiosis-related gene, nifH, reproduced the housekeeping genes phylogenies. The study of morphological, phenotypical and physiological features, including cellular fatty acid composition of the novel isolates demonstrated their unique profile regarding close reference Microvirga strains. Strains LmiM8T, LmiE10 and LluTb3 were able to nodulate several Lupinus spp. Based on genetic, genomic and phenotypic data presented in this study, these strains should be grouped within a new species for which the name Microvirga tunisiensis sp. nov. is proposed (type strain LmiM8T=CECT 9163T, LMG 29689T).},
}
@article {pmid31175441,
year = {2019},
author = {Pietras, M},
title = {First record of North American fungus Rhizopogon pseudoroseolus in Australia and prediction of its occurrence based on climatic niche and symbiotic partner preferences.},
journal = {Mycorrhiza},
volume = {29},
number = {4},
pages = {397-401},
doi = {10.1007/s00572-019-00899-x},
pmid = {31175441},
issn = {1432-1890},
support = {DEC-2015/16/S/NZ9/00370//Narodowe Centrum Nauki/ ; },
mesh = {Australia ; Basidiomycota/classification/genetics/*isolation &amp; purification/*physiology ; Climate ; New Zealand ; North America ; Phylogeny ; Pinus/*microbiology/physiology ; *Symbiosis ; Tasmania ; },
abstract = {In 2017 a North American fungus, Rhizopogon pseudoroseolus (Boletales, Basidiomycota), formerly known in Oceania as only occurring in New Zealand, was found for the first time in South Australia. The morphological identification of collected specimens was confirmed using an internal transcribed spacer barcoding approach. In this study, the biogeography of R. pseudoroseolus is also presented, based on sporocarp and ectomycorrhiza records. Species distribution modeling implemented in MaxEnt was used to estimate the distribution of the potential range of R. pseudoroseolus in Australia and New Zealand. The obtained model illustrates, in the background of climatic variables and distribution of a symbiotic partner, its wide range of suitable habitats in New Zealand, South-East Australia, and Tasmania. Precipitation of the coldest quarters and annual mean temperature are important factors influencing the potential distribution of the fungus. The occurrence of Pinus radiata, the ectomycorrhizal partner of R. pseudoroseolus, is also an important factor limiting expansion of the fungus' invasion range.},
}
@article {pmid29563606,
year = {2018},
author = {Ertz, D and Guzow-Krzemińska, B and Thor, G and Łubek, A and Kukwa, M},
title = {Photobiont switching causes changes in the reproduction strategy and phenotypic dimorphism in the Arthoniomycetes.},
journal = {Scientific reports},
volume = {8},
number = {1},
pages = {4952},
pmid = {29563606},
issn = {2045-2322},
mesh = {Adaptation, Physiological ; Ascomycota/*genetics ; Chloroplasts/genetics ; DNA, Plant/genetics ; Host Microbial Interactions/*physiology ; Lichens/classification/*microbiology/physiology ; Photosynthesis/physiology ; *Phylogeny ; Ribulose-Bisphosphate Carboxylase/genetics ; Symbiosis/*physiology ; },
abstract = {Phylogenetic analyses using mtSSU and nuITS sequences of Buellia violaceofusca (previously placed in Lecanoromycetes), a sterile, sorediate lichen having a trebouxioid photobiont, surprisingly prove that the species is conspecific with Lecanographa amylacea (Arthoniomycetes), a fertile, esorediate species with a trentepohlioid photobiont. These results suggest that L. amylacea and B. violaceofusca are photomorphs of the same mycobiont species, which, depending on the photobiont type, changes the morphology and the reproduction strategy. This is the first example of a lichenized fungus that can select between Trebouxia (Trebouxiophyceae) and trentepohlioid (Ulvophyceae) photobionts. Trebouxia photobionts from the sorediate morphotype belong to at least three different phylogenetic clades, and the results suggest that Lecanographa amylacea can capture the photobiont of other lichens such as Chrysothrix candelaris to form the sorediate morphotype. Phylogenetic analyses based on rbcL DNA data suggest that the trentepohlioid photobiont of L. amylacea is closely related to Trentepohlia isolated from fruticose lichens. The flexibility in the photobiont choice enables L. amylacea to use a larger range of tree hosts. This strategy helps the lichen to withstand changes of environmental conditions, to widen its distribution range and to increase its population size, which is particularly important for the survival of this rare species.},
}
@article {pmid29526588,
year = {2018},
author = {Turelli, M and Cooper, BS and Richardson, KM and Ginsberg, PS and Peckenpaugh, B and Antelope, CX and Kim, KJ and May, MR and Abrieux, A and Wilson, DA and Bronski, MJ and Moore, BR and Gao, JJ and Eisen, MB and Chiu, JC and Conner, WR and Hoffmann, AA},
title = {Rapid Global Spread of wRi-like Wolbachia across Multiple Drosophila.},
journal = {Current biology : CB},
volume = {28},
number = {6},
pages = {963-971.e8},
pmid = {29526588},
issn = {1879-0445},
support = {R01 GM104325/GM/NIGMS NIH HHS/United States ; R35 GM124701/GM/NIGMS NIH HHS/United States ; S10 RR027303/RR/NCRR NIH HHS/United States ; S10 RR029668/RR/NCRR NIH HHS/United States ; /HHMI/Howard Hughes Medical Institute/United States ; },
mesh = {Animals ; Biological Evolution ; DNA, Mitochondrial/analysis/genetics ; Disease Transmission, Infectious/veterinary ; Drosophila/*genetics/microbiology ; Evolution, Molecular ; Genome/genetics ; Infectious Disease Transmission, Vertical/veterinary ; Introduced Species ; Phylogeny ; Symbiosis/genetics ; Wolbachia/*genetics/pathogenicity ; },
abstract = {Maternally transmitted Wolbachia, Spiroplasma, and Cardinium bacteria are common in insects [1], but their interspecific spread is poorly understood. Endosymbionts can spread rapidly within host species by manipulating host reproduction, as typified by the global spread of wRi Wolbachia observed in Drosophila simulans [2, 3]. However, because Wolbachia cannot survive outside host cells, spread between distantly related host species requires horizontal transfers that are presumably rare [4-7]. Here, we document spread of wRi-like Wolbachia among eight highly diverged Drosophila hosts (10-50 million years) over only about 14,000 years (5,000-27,000). Comparing 110 wRi-like genomes, we find ≤0.02% divergence from the wRi variant that spread rapidly through California populations of D. simulans. The hosts include both globally invasive species (D. simulans, D. suzukii, and D. ananassae) and narrowly distributed Australian endemics (D. anomalata and D. pandora) [8]. Phylogenetic analyses that include mtDNA genomes indicate introgressive transfer of wRi-like Wolbachia between closely related species D. ananassae, D. anomalata, and D. pandora but no horizontal transmission within species. Our analyses suggest D. ananassae as the Wolbachia source for the recent wRi invasion of D. simulans and D. suzukii as the source of Wolbachia in its sister species D. subpulchrella. Although six of these wRi-like variants cause strong cytoplasmic incompatibility, two cause no detectable reproductive effects, indicating that pervasive mutualistic effects [9, 10] complement the reproductive manipulations for which Wolbachia are best known. &quot;Super spreader&quot; variants like wRi may be particularly useful for controlling insect pests and vector-borne diseases with Wolbachia transinfections [11].},
}
@article {pmid29526587,
year = {2018},
author = {Nunes, CEP and Maruyama, PK and Azevedo-Silva, M and Sazima, M},
title = {Parasitoids Turn Herbivores into Mutualists in a Nursery System Involving Active Pollination.},
journal = {Current biology : CB},
volume = {28},
number = {6},
pages = {980-986.e3},
doi = {10.1016/j.cub.2018.02.013},
pmid = {29526587},
issn = {1879-0445},
mesh = {Animals ; Female ; Flowers ; Fruit ; Herbivory/physiology ; Larva ; Orchidaceae/metabolism ; Parasites ; Pollen ; Pollination/physiology ; Reproduction ; Seeds ; Symbiosis/physiology ; Wasps/metabolism/*parasitology ; Weevils/*metabolism/parasitology ; },
abstract = {Nursery pollination involves pollinators that lay eggs on the flowers they pollinate and have their brood fed on flower parts or developing ovules [1-4]. Active pollination, a ritualistic behavioral sequence shown by nursery pollinators when transferring pollen from anthers to stigmas, is known in only four plant lineages [5-8], including the classical examples of fig trees-fig wasps and yuccas-yucca moths [5, 6]. We report in detail a system in which weevils actively pollinate orchids prior to having their larvae fed on the developing fruits. Sampling over five years revealed that although weevils trigger fruit set, this interaction is negative for the plant as weevil larvae often consume all contents of infested fruits. However, part of weevil-infested fruits is often &quot;rescued&quot; by parasitoid wasps, which kill the weevil larvae before all fruit content is consumed (Figure 1). &quot;Rescued&quot; fruits present high seed viability and biomass similar to that of non-infested fruits, much higher than that of fruits with weevils only. Hence, parasitoids mediate the fitness consequences of the interaction between the plant and its parasitic pollinator. Weevils constitute a megadiverse group of herbivores commonly reported as florivores [9] but are also appreciated as flower-ovipositing pollinators of cycads and palms [4, 10-13] and were previously recorded carrying orchid pollinaria [14-16]. The orchid-weevil system presented here shows that plant-floral visitor interaction outcome can be mediated by a third party (parasitoids) and illustrates a way by which the biological context may allow the emergence and persistence of active nursery pollination behavior in nature.},
}
@article {pmid31587644,
year = {2019},
author = {Richards, TA and Massana, R and Pagliara, S and Hall, N},
title = {Single cell ecology.},
journal = {Philosophical transactions of the Royal Society of London. Series B, Biological sciences},
volume = {374},
number = {1786},
pages = {20190076},
doi = {10.1098/rstb.2019.0076},
pmid = {31587644},
issn = {1471-2970},
abstract = {Cells are the building blocks of life, from single-celled microbes through to multi-cellular organisms. To understand a multitude of biological processes we need to understand how cells behave, how they interact with each other and how they respond to their environment. The use of new methodologies is changing the way we study cells allowing us to study them on minute scales and in unprecedented detail. These same methods are allowing researchers to begin to sample the vast diversity of microbes that dominate natural environments. The aim of this special issue is to bring together research and perspectives on the application of new approaches to understand the biological properties of cells, including how they interact with other biological entities. This article is part of a discussion meeting issue 'Single cell ecology'.},
}
@article {pmid31347757,
year = {2019},
author = {Clark, RE and Gutierrez Illan, J and Comerford, MS and Singer, MS},
title = {Keystone mutualism influences forest tree growth at a landscape scale.},
journal = {Ecology letters},
volume = {22},
number = {10},
pages = {1599-1607},
doi = {10.1111/ele.13352},
pmid = {31347757},
issn = {1461-0248},
support = {DEB-1404177//NSF Doctoral Dissertation Improvement/ ; },
mesh = {Animals ; *Ants ; *Forests ; *Herbivory ; Symbiosis ; Trees/*growth &amp; development ; },
abstract = {Interactions between ants and phloem-feeding herbivores are characterised as a keystone mutualism because they restructure arthropod communities and generate trophic cascades. Keystone interactions in terrestrial food webs are hypothesised to depend on herbivore community structure and bottom-up effects on plant growth. Here, we tested this prediction at a landscape scale with a long-term ant-exclusion experiment on hickory saplings in the context of spatial variation in herbivore community structure and habitat quality. We quantified top-down effects of ants, herbivore communities as well as abiotic factors impacting hickory shoot growth. We found that ants influenced shoot growth via strong, context-dependent, compensatory effects, with clear cascading benefits only when phloem-feeders were present and chewing herbivore abundance was high. By contrast, while several landscape variables predicted hickory growth, they did not mediate the strength of cascading effects of ants. These results suggest that ant/sap-feeder mutualisms may regulate forest productivity by mediating effects of multiple herbivore guilds.},
}
@article {pmid31243858,
year = {2019},
author = {Valdovinos, FS},
title = {Mutualistic networks: moving closer to a predictive theory.},
journal = {Ecology letters},
volume = {22},
number = {9},
pages = {1517-1534},
doi = {10.1111/ele.13279},
pmid = {31243858},
issn = {1461-0248},
support = {DEB-1834497//US NSF/ ; U061182//University of Michigan MICDE/ ; U061182//University of Michigan/ ; },
mesh = {Animals ; Appetitive Behavior ; Biodiversity ; *Models, Biological ; *Plants ; Pollination ; Population Dynamics ; Reproduction ; *Symbiosis ; },
abstract = {Plant-animal mutualistic networks sustain terrestrial biodiversity and human food security. Global environmental changes threaten these networks, underscoring the urgency for developing a predictive theory on how networks respond to perturbations. Here, I synthesise theoretical advances towards predicting network structure, dynamics, interaction strengths and responses to perturbations. I find that mathematical models incorporating biological mechanisms of mutualistic interactions provide better predictions of network dynamics. Those mechanisms include trait matching, adaptive foraging, and the dynamic consumption and production of both resources and services provided by mutualisms. Models incorporating species traits better predict the potential structure of networks (fundamental niche), while theory based on the dynamics of species abundances, rewards, foraging preferences and reproductive services can predict the extremely dynamic realised structures of networks, and may successfully predict network responses to perturbations. From a theoretician's standpoint, model development must more realistically represent empirical data on interaction strengths, population dynamics and how these vary with perturbations from global change. From an empiricist's standpoint, theory needs to make specific predictions that can be tested by observation or experiments. Developing models using short-term empirical data allows models to make longer term predictions of community dynamics. As more longer term data become available, rigorous tests of model predictions will improve.},
}
@article {pmid30963197,
year = {2019},
author = {Xu, J and Koyanagi, Y and Isogai, E and Nakamura, S},
title = {Effects of fermentation products of the commensal bacterium Clostridium ramosum on motility, intracellular pH, and flagellar synthesis of enterohemorrhagic Escherichia coli.},
journal = {Archives of microbiology},
volume = {201},
number = {6},
pages = {841-846},
doi = {10.1007/s00203-019-01656-6},
pmid = {30963197},
issn = {1432-072X},
support = {18J10834//Japan Society for the Promotion of Science/ ; },
mesh = {Clostridium/*chemistry/metabolism ; Enterohemorrhagic Escherichia coli/chemistry/*cytology/genetics/metabolism ; Escherichia coli Proteins/genetics/*metabolism ; Fatty Acids, Volatile/metabolism ; Fermentation ; Flagella/genetics/*metabolism ; Humans ; Hydrogen-Ion Concentration ; Intestines/microbiology ; Symbiosis ; },
abstract = {The flagellum and motility are crucial virulence factors for many pathogenic bacteria. In general, pathogens invade and translocate through motility and adhere to specific tissue via flagella. Therefore, the motility and flagella of pathogens are effectual targets for attenuation. Here, we show that the fermentation products of Clostridium ramosum, a commensal intestinal bacterium, decrease the intracellular pH of enterohemorrhagic Escherichia coli (EHEC) and influence its swimming motility. Quantifications of flagellar rotation in individual EHEC cells showed an increase in reversal frequency and a decrease in rotation rate in the presence of C. ramosum fermentation products. Furthermore, the C. ramosum fermentation products affected synthesis of flagellar filaments. The results were reproduced by a combination of organic acids under acidic conditions. Short-chain fatty acids produced by microbes in the gut flora are beneficial for the host, e.g. they prevent infection. Thus, C. ramosum could affect the physiologies of other enteric microbes and host tissues.},
}
@article {pmid30953092,
year = {2019},
author = {Liu, X and Qiu, W and Rao, B and Cao, Y and Fang, X and Yang, J and Jiang, G and Zhong, Z and Zhu, J},
title = {Bacterioferritin comigratory protein is important in hydrogen peroxide resistance, nodulation, and nitrogen fixation in Azorhizobium caulinodans.},
journal = {Archives of microbiology},
volume = {201},
number = {6},
pages = {823-831},
doi = {10.1007/s00203-019-01654-8},
pmid = {30953092},
issn = {1432-072X},
support = {2015CB150600//973 project/ ; 31770096//National Natural Science Foundation of China/ ; 31470202//National Natural Science Foundation of China/ ; },
mesh = {Azorhizobium caulinodans/drug effects/genetics/*physiology ; Bacterial Proteins/genetics/*metabolism ; Cytochrome b Group/genetics/*metabolism ; Fabaceae/microbiology/physiology ; Ferritins/genetics/*metabolism ; Hydrogen Peroxide/*pharmacology ; *Nitrogen Fixation ; Plant Root Nodulation ; Root Nodules, Plant/microbiology ; Symbiosis ; },
abstract = {Reactive oxygen species are not only harmful for rhizobia but also required for the establishment of symbiotic interactions between rhizobia and their legume hosts. In this work, we first investigated the preliminary role of the bacterioferritin comigratory protein (BCP), a member of the peroxiredoxin family, in the nitrogen-fixing bacterium Azorhizobium caulinodans. Our data revealed that the bcp-deficient strain of A. caulinodans displayed an increased sensitivity to inorganic hydrogen peroxide (H2O2) but not to two organic peroxides in a growth-phase-dependent manner. Meanwhile, BCP was found to be involved in catalase activity under relatively low H2O2 conditions. Furthermore, nodulation and N2 fixation were significantly impaired by mutation of the bcp gene in A. caulinodans. Our work initially documented the importance of BCP in the bacterial defence against H2O2 in the free-living stage of rhizobia and during their symbiotic interactions with legumes. Molecular signalling in vivo is required to decipher the holistic functions of BCP in A. caulinodans as well as in other rhizobia.},
}
@article {pmid29897399,
year = {2018},
author = {Reiter, N and Lawrie, AC and Linde, CC},
title = {Matching symbiotic associations of an endangered orchid to habitat to improve conservation outcomes.},
journal = {Annals of botany},
volume = {122},
number = {6},
pages = {947-959},
pmid = {29897399},
issn = {1095-8290},
mesh = {Basidiomycota/*physiology ; *Conservation of Natural Resources ; *Ecosystem ; Endangered Species ; Orchidaceae/*microbiology/*physiology ; *Symbiosis ; Victoria ; },
abstract = {Background and Aims: An understanding of mycorrhizal variation, orchid seed germination temperature and the effect of co-occurring plant species could be critical for optimizing conservation translocations of endangered plants with specialized mycorrhizal associations.<br><br>Methods: Focusing on the orchid Thelymitra epipactoides, we isolated mycorrhizal fungi from ten plants within each of three sites; Shallow Sands Woodland (SSW), Damp Heathland (DH) and Coastal Heathland Scrub (CHS). Twenty-seven fungal isolates were tested for symbiotic germination under three 24 h temperature cycles: 12 °C for 16 h-16 °C for 8 h, 16 °C for 16 h-24 °C for 8 h or 27 °C constant. Fungi were sequenced using the internal transcribed spacer (ITS), nuclear large subunit 1 (nLSU1), nLSU2 and mitochondrial large rRNA gene (mtLSU). Orchids were grown to maturity and co-planted with each of ten associated plant species in a glasshouse experiment with tuber width measured at 12 months after co-planting.<br><br>Key Results: Two Tulasnella fungal lineages were isolated and identified by phylogenetic analyses, operational taxonomic unit 1 (OTU1) and 'T. asymmetrica'. Fungal lineages were specific to sites and did not co-occur. OTU1 (from the SSW site) germinated seed predominantly at 12-16 °C (typical of autumn-winter temperature) whereas 'T. asymmetrica' (from the DH and CHS sites) germinated seed across all three temperature ranges. There was no difference in the growth of adult orchids germinated with different OTUs. There was a significant reduction in tuber size of T. epipactoides when co-planted with six of the commonly co-occurring plant species.<br><br>Conclusions: We found that orchid fungal lineages and their germination temperature can change with habitat, and established that translocation sites can be optimized with knowledge of co-occurring plant interactions. For conservation translocations, particularly under a changing climate, we recommend that plants should be grown with mycorrhizal fungi tailored to the recipient site.},
}
@article {pmid29884754,
year = {2018},
author = {Lugli, GA and Mancino, W and Milani, C and Duranti, S and Turroni, F and van Sinderen, D and Ventura, M},
title = {Reconstruction of the Bifidobacterial Pan-Secretome Reveals the Network of Extracellular Interactions between Bifidobacteria and the Infant Gut.},
journal = {Applied and environmental microbiology},
volume = {84},
number = {16},
pages = {},
pmid = {29884754},
issn = {1098-5336},
mesh = {Bifidobacterium/*genetics/*metabolism ; Bifidobacterium longum/genetics/metabolism ; Feces/microbiology ; Gastrointestinal Microbiome/*genetics ; Glycomics ; Humans ; Infant ; Intestines/*microbiology ; *Metabolome ; Metagenome ; Milk, Human/metabolism ; Oligosaccharides/metabolism ; Proteome ; Symbiosis ; },
abstract = {The repertoire of secreted proteins decoded by a microorganism represents proteins released from or associated with the cell surface. In gut commensals, such as bifidobacteria, these proteins are perceived to be functionally relevant, as they regulate the interaction with the gut environment. In the current study, we screened the predicted proteome of over 300 bifidobacterial strains among the currently recognized bifidobacterial species to generate a comprehensive database encompassing bifidobacterial extracellular proteins. A glycobiome analysis of this predicted bifidobacterial secretome revealed that a correlation exists between particular bifidobacterial species and their capability to hydrolyze human milk oligosaccharides (HMOs) and intestinal glycoconjugates, such as mucin. Furthermore, an exploration of metatranscriptomic data sets of the infant gut microbiota allowed the evaluation of the expression of bifidobacterial genes encoding extracellular proteins, represented by ABC transporter substrate-binding proteins and glycoside hydrolases enzymes involved in the degradation of human milk oligosaccharides and mucin. Overall, this study provides insights into how bifidobacteria interact with their natural yet highly complex environment, the infant gut.IMPORTANCE The ecological success of bifidobacteria relies on the activity of extracellular proteins that are involved in the metabolism of nutrients and the interaction with the environment. To date, information on secreted proteins encoded by bifidobacteria is incomplete and just related to few species. In this study, we reconstructed the bifidobacterial pan-secretome, revealing extracellular proteins that modulate the interaction of bifidobacteria with their natural environment. Furthermore, a survey of the secretion systems between bifidobacterial genomes allowed the identification of a conserved Sec-dependent secretion machinery in all the analyzed genomes and the Tat protein translocation system in the chromosomes of 23 strains belonging to Bifidobacterium longum subsp. longum and Bifidobacterium aesculapii.},
}
@article {pmid29878049,
year = {2018},
author = {Izzo, TJ and Fernandez Piedade, MT and Dáttilo, W},
title = {Postponing the production of ant domatia as a strategy promoting an escape from flooding in an Amazonian myrmecophyte.},
journal = {Annals of botany},
volume = {122},
number = {6},
pages = {985-991},
pmid = {29878049},
issn = {1095-8290},
mesh = {Animals ; Ants/*physiology ; Brazil ; *Floods ; Herbivory ; Melastomataceae/anatomy &amp; histology/*physiology ; Plant Leaves/anatomy &amp; histology/physiology ; *Symbiosis ; },
abstract = {Background and Aims: Even when adapted to flooding environments, the spatial distribution, growing strategies and anti-herbivore defences of plants face stressful conditions. Here we describe the effects of flooding on carbon allocation on growth, domatia and leaf production, and the herbivory on the myrmecophyte domatia-bearing Tococa coronata Benth. (Melastomataceae) growing along river banks in the Amazon region.<br><br>Methods: In an area of 80 000 m2 of riparian forest along the Juruena River we actively searched for individuals of T. coronata. In each plant we evaluated the size of the plant when producing the first domatium and determined its best predictor: (1) plant total height; (2) size of plants above flood level; or (3) length of time each plant spent underwater. We also compared the herbivory, internode elongation, foliar asymmetry and specific leaf weight between T. coronata individuals growing above and below the maximum flooding level. The distance to the river and the height of the first domatium produced were compared between T. coronata and its sympatric congener, T. bulifera.<br><br>Key Results: We found that T. coronata invests in rapid growth in the early ontogenetic stages through an elongation of internodes rather than in constitutive anti-herbivore defences to leaves or domatia to exceed the maximum flooding level. Consequently, its leaf herbivory was higher when compared with those produced above the flooding level. Individuals with leaves above flood levels produce coriaceous leaves and ant-domatias. Thus, flooding seems to trigger changes in growth strategies of the species. Furthermore, T. coronata occurs within the flood level, whereas its congener T. bullifera invariably occurs at sites unreachable by floods.<br><br>Conclusion: Even in conditions of high stress, T. coronata presents both physiological and adaptive strategies that allow for colonization and establishment within flooded regions. These mechanisms involve an extreme trade-off of postponing adult plant characteristics to rapid growth to escape flooding while minimizing carbon allocation to defence.},
}
@article {pmid29803476,
year = {2018},
author = {González-Escobar, JL and Grajales-Lagunes, A and Smoliński, A and Chagolla-López, A and De Léon-Rodríguez, A and Barba de la Rosa, AP},
title = {Microbiota of edible Liometopum apiculatum ant larvae reveals potential functions related to their nutritional value.},
journal = {Food research international (Ottawa, Ont.)},
volume = {109},
number = {},
pages = {497-505},
doi = {10.1016/j.foodres.2018.04.049},
pmid = {29803476},
issn = {1873-7145},
mesh = {Animals ; Ants/*microbiology ; Bacteria/classification/genetics/*isolation &amp; purification ; Female ; Food Analysis/methods ; Host-Pathogen Interactions ; Larva/microbiology ; Male ; Metagenomics ; *Microbiota ; *Nutritive Value ; Ribotyping ; Symbiosis ; },
abstract = {Edible insects, due to their high nutritive value, are currently considered as a potential renewable source for food and feed production. Liometopum apiculatum ants are widely distributed in arid and semi-arid ecosystems and their larvae (escamoles) are considered as a delicacy, however the microbial importance in L. apiculatum nutritional ecology is unknown. The aim of this research was to characterize the microorganisms associated with both L. apiculatum larvae and the reproductive adult ants using the 16S rRNA gene sequencing and culturomics approaches. The obligate endosymbionts were also investigated through microscopic analysis. The most abundant Phylum identified by sequencing in the larvae was Firmicutes while in adult ants was Proteobacteria. Interestingly, the culturomics results showed 15 genera corresponding to the bacteria identified by sequencing analysis. Particularly, it was observed a large population of nitrogen-fixing bacteria, which could be linked with the high protein content in escamoles. Endosymbionts were detected in bacteoriocytes, these bacteria are related with vitamins and essential amino acids biosynthesis, and both compounds contributing to the high nutritional value of escamoles. This is the first report of the microorganisms present in the escamolera ant ensuring their safety as food and opening new areas of nutritional ecological and food processing.},
}
@article {pmid29752265,
year = {2018},
author = {Stoudenmire, JL and Essock-Burns, T and Weathers, EN and Solaimanpour, S and Mrázek, J and Stabb, EV},
title = {An Iterative, Synthetic Approach To Engineer a High-Performance PhoB-Specific Reporter.},
journal = {Applied and environmental microbiology},
volume = {84},
number = {14},
pages = {},
pmid = {29752265},
issn = {1098-5336},
mesh = {Aliivibrio/genetics ; Aliivibrio fischeri/*genetics/metabolism ; Animals ; Bacterial Proteins/*genetics ; Base Sequence ; Binding Sites ; Decapodiformes/microbiology ; Escherichia coli/genetics ; *Gene Expression Regulation, Bacterial ; Photobacterium/genetics ; *Promoter Regions, Genetic ; Salmonella enterica/genetics ; Sequence Analysis ; Symbiosis ; Synthetic Biology ; },
abstract = {Transcriptional reporters are common tools for analyzing either the transcription of a gene of interest or the activity of a specific transcriptional regulator. Unfortunately, the latter application has the shortcoming that native promoters did not evolve as optimal readouts for the activity of a particular regulator. We sought to synthesize an optimized transcriptional reporter for assessing PhoB activity, aiming for maximal &quot;on&quot; expression when PhoB is active, minimal background in the &quot;off&quot; state, and no control elements for other regulators. We designed specific sequences for promoter elements with appropriately spaced PhoB-binding sites, and at 19 additional intervening nucleotide positions for which we did not predict sequence-specific effects, the bases were randomized. Eighty-three such constructs were screened in Vibrio fischeri, enabling us to identify bases at particular randomized positions that significantly correlated with high-level &quot;on&quot; or low-level &quot;off&quot; expression. A second round of promoter design rationally constrained 13 additional positions, leading to a reporter with high-level PhoB-dependent expression, essentially no background, and no other known regulatory elements. As expressed reporters, we used both stable and destabilized variants of green fluorescent protein (GFP), the latter of which has a half-life of 81 min in V. fischeri In culture, PhoB induced the reporter when phosphate was depleted to a concentration below 10 μM. During symbiotic colonization of its host squid, Euprymna scolopes, the reporter indicated heterogeneous phosphate availability in different light-organ microenvironments. Finally, testing this construct in other members of the Proteobacteria demonstrated its broader utility. The results illustrate how a limited ability to predict synthetic promoter-reporter performance can be overcome through iterative screening and reengineering.IMPORTANCE Transcriptional reporters can be powerful tools for assessing when a particular regulator is active; however, native promoters may not be ideal for this purpose. Optimal reporters should be specific to the regulator being examined and should maximize the difference between the &quot;on&quot; and &quot;off&quot; states; however, these properties are distinct from the selective pressures driving the evolution of natural promoters. Synthetic promoters offer a promising alternative, but our understanding often does not enable fully predictive promoter design, and the large number of alternative sequence possibilities can be intractable. In a synthetic promoter region with over 34 billion sequence variants, we identified bases correlated with favorable performance by screening only 83 candidates, allowing us to rationally constrain our design. We thereby generated an optimized reporter that is induced by PhoB and used it to explore the low-phosphate response of V. fischeri This promoter design strategy will facilitate the engineering of other regulator-specific reporters.},
}
@article {pmid29728387,
year = {2018},
author = {McCully, AL and Behringer, MG and Gliessman, JR and Pilipenko, EV and Mazny, JL and Lynch, M and Drummond, DA and McKinlay, JB},
title = {An Escherichia coli Nitrogen Starvation Response Is Important for Mutualistic Coexistence with Rhodopseudomonas palustris.},
journal = {Applied and environmental microbiology},
volume = {84},
number = {14},
pages = {},
pmid = {29728387},
issn = {1098-5336},
support = {F32 GM123703/GM/NIGMS NIH HHS/United States ; },
mesh = {Ammonium Compounds/metabolism ; Carbon/metabolism ; Cation Transport Proteins/genetics/metabolism ; Coculture Techniques ; Culture Media/chemistry ; Escherichia coli/*genetics/metabolism ; Escherichia coli Proteins/genetics/metabolism ; Fermentation ; Gene Expression Regulation, Bacterial ; Nitrogen/*metabolism ; PII Nitrogen Regulatory Proteins/genetics/metabolism ; Proteomics ; Rhodopseudomonas/*genetics/metabolism ; Sequence Analysis, RNA ; *Symbiosis ; Transcription Factors/genetics/metabolism ; Transcriptome ; },
abstract = {Microbial mutualistic cross-feeding interactions are ubiquitous and can drive important community functions. Engaging in cross-feeding undoubtedly affects the physiology and metabolism of individual species involved. However, the nature in which an individual species' physiology is influenced by cross-feeding and the importance of those physiological changes for the mutualism have received little attention. We previously developed a genetically tractable coculture to study bacterial mutualisms. The coculture consists of fermentative Escherichia coli and phototrophic Rhodopseudomonas palustris In this coculture, E. coli anaerobically ferments sugars into excreted organic acids as a carbon source for R. palustris In return, a genetically engineered R. palustris strain constitutively converts N2 into NH4+, providing E. coli with essential nitrogen. Using transcriptome sequencing (RNA-seq) and proteomics, we identified transcript and protein levels that differ in each partner when grown in coculture versus monoculture. When in coculture with R. palustris, E. coli gene expression changes resembled a nitrogen starvation response under the control of the transcriptional regulator NtrC. By genetically disrupting E. coli NtrC, we determined that a nitrogen starvation response is important for a stable coexistence, especially at low R. palustris NH4+ excretion levels. Destabilization of the nitrogen starvation regulatory network resulted in variable growth trends and, in some cases, extinction. Our results highlight that alternative physiological states can be important for survival within cooperative cross-feeding relationships.IMPORTANCE Mutualistic cross-feeding between microbes within multispecies communities is widespread. Studying how mutualistic interactions influence the physiology of each species involved is important for understanding how mutualisms function and persist in both natural and applied settings. Using a bacterial mutualism consisting of Rhodopseudomonas palustris and Escherichia coli growing cooperatively through bidirectional nutrient exchange, we determined that an E. coli nitrogen starvation response is important for maintaining a stable coexistence. The lack of an E. coli nitrogen starvation response ultimately destabilized the mutualism and, in some cases, led to community collapse after serial transfers. Our findings thus inform on the potential necessity of an alternative physiological state for mutualistic coexistence with another species compared to the physiology of species grown in isolation.},
}
@article {pmid29728381,
year = {2018},
author = {Høj, L and Levy, N and Baillie, BK and Clode, PL and Strohmaier, RC and Siboni, N and Webster, NS and Uthicke, S and Bourne, DG},
title = {Crown-of-Thorns Sea Star Acanthaster cf. solaris Has Tissue-Characteristic Microbiomes with Potential Roles in Health and Reproduction.},
journal = {Applied and environmental microbiology},
volume = {84},
number = {13},
pages = {},
pmid = {29728381},
issn = {1098-5336},
mesh = {Animal Diseases ; Animals ; Australia ; Bacteria/*classification ; Coral Reefs ; Dysbiosis ; Host Microbial Interactions/*physiology ; Male ; Microbiota/*physiology ; Phylogeny ; *Reproduction ; Seawater/microbiology ; Spiroplasma ; Starfish/*microbiology ; Symbiosis ; Tenericutes ; },
abstract = {Outbreaks of coral-eating crown-of-thorns sea stars (CoTS; Acanthaster species complex) cause substantial coral loss; hence, there is considerable interest in developing prevention and control strategies. We characterized the microbiome of captive CoTS and assessed whether dysbiosis was evident in sea stars during a disease event. Most tissue types had a distinct microbiome. The exception was female gonads, in which the microbiomes were highly variable among individuals. Male gonads were dominated (>97% of reads) by a single Mollicutes-related operational taxonomic unit (OTU). Detailed phylogenetic and microscopy analysis demonstrated the presence of a novel Spiroplasma-related bacterium in the spermatogenic layer. Body wall samples had high relative abundance (43 to 64% of reads) of spirochetes, likely corresponding to subcuticular symbionts reported from many echinoderms. Tube feet were characterized by Hyphomonadaceae (24 to 55% of reads). Pyloric cecal microbiomes had high alpha diversity, comprising many taxa commonly found in gastrointestinal systems. The order Oceanospirillales (genera Endozoicomonas and Kistimonas) was detected in all tissues. A microbiome shift occurred in diseased individuals although differences between tissue types were retained. The relative abundance of spirochetes was significantly reduced in diseased individuals. Kistimonas was present in all diseased individuals and significantly associated with diseased tube feet, but its role in disease causation is unknown. While Arcobacter was significantly associated with diseased tissues and Vibrionaceae increased in diversity, no single OTU was detected in all diseased individuals, suggesting opportunistic proliferation of these taxa in this case. This study shows that CoTS have tissue-characteristic bacterial communities and identifies taxa that could play a role in reproduction and host health.IMPORTANCE Coral-eating crown-of-thorns sea stars (CoTS; Acanthaster species complex) are native to the Indo-Pacific, but during periodic population outbreaks they can reach extreme densities (>1,000 starfish per hectare) and function as a pest species. On the Great Barrier Reef, Australia, CoTS have long been considered one of the major contributors to coral loss. There has been significant investment in a targeted control program using lethal injection, and there is interest in developing additional and complementary technologies that can increase culling efficiencies. The biology of CoTS has been studied extensively, but little is known about their associated microbiome. This cultivation-independent analysis of the CoTS microbiome provides a baseline for future analyses targeting the functional role of symbionts, the identification of pathogens, or the development of reproduction manipulators.},
}
@article {pmid29720714,
year = {2018},
author = {Pereira, TN and Rocha, MN and Sucupira, PHF and Carvalho, FD and Moreira, LA},
title = {Wolbachia significantly impacts the vector competence of Aedes aegypti for Mayaro virus.},
journal = {Scientific reports},
volume = {8},
number = {1},
pages = {6889},
pmid = {29720714},
issn = {2045-2322},
mesh = {Aedes/microbiology/*virology ; Animals ; Cell Line ; Cells, Cultured ; Female ; Humans ; Mosquito Vectors/microbiology/*virology ; Symbiosis ; Togaviridae/pathogenicity/*physiology ; Togaviridae Infections/transmission ; *Virus Replication ; Wolbachia/*pathogenicity ; },
abstract = {Wolbachia, an intracellular endosymbiont present in up to 70% of all insect species, has been suggested as a sustainable strategy for the control of arboviruses such as Dengue, Zika and Chikungunya. As Mayaro virus outbreaks have also been reported in Latin American countries, the objective of this study was to evaluate the vector competence of Brazilian field-collected Ae. aegypti and the impact of Wolbachia (wMel strain) upon this virus. Our in vitro studies with Aag2 cells showed that Mayaro virus can rapidly multiply, whereas in wMel-infected Aag2 cells, viral growth was significantly impaired. In addition, C6/36 cells seem to have alterations when infected by Mayaro virus. In vivo experiments showed that field-collected Ae. aegypti mosquitoes are highly permissive to Mayaro virus infection, and high viral prevalence was observed in the saliva. On the other hand, Wolbachia-harboring mosquitoes showed significantly impaired capability to transmit Mayaro virus. Our results suggest that the use of Wolbachia-harboring mosquitoes may represent an effective mechanism for the reduction of Mayaro virus transmission throughout Latin America.},
}
@article {pmid29689202,
year = {2018},
author = {de Vries, J and Archibald, JM},
title = {Plastid genomes.},
journal = {Current biology : CB},
volume = {28},
number = {8},
pages = {R336-R337},
doi = {10.1016/j.cub.2018.01.027},
pmid = {29689202},
issn = {1879-0445},
mesh = {Cyanobacteria/genetics ; Evolution, Molecular ; Genome, Plastid/*genetics/physiology ; Phylogeny ; Plants/genetics ; Plastids/*genetics/*metabolism ; Symbiosis/genetics/physiology ; },
abstract = {de Vries and Archibald introduce the topic of plastid genomes - prokaryotic genomes housed within eukaryotic algae and plants.},
}
@article {pmid29615668,
year = {2018},
author = {Pandey, SS and Singh, S and Pandey, H and Srivastava, M and Ray, T and Soni, S and Pandey, A and Shanker, K and Babu, CSV and Banerjee, S and Gupta, MM and Kalra, A},
title = {Endophytes of Withania somnifera modulate in planta content and the site of withanolide biosynthesis.},
journal = {Scientific reports},
volume = {8},
number = {1},
pages = {5450},
pmid = {29615668},
issn = {2045-2322},
mesh = {Biomass ; Endophytes/*physiology ; Photosynthesis ; Pigments, Biological/metabolism ; Plant Leaves/metabolism ; Plant Roots/metabolism ; Symbiosis ; Withania/genetics/*metabolism/*microbiology ; Withanolides/*metabolism ; },
abstract = {Tissue specific biosynthesis of secondary metabolites is a distinguished feature of medicinal plants. Withania somnifera, source of pharmaceutically important withanolides biosynthesizes withaferin-A in leaves and withanolide-A in roots. To increase the in planta withanolides production, a sustainable approach needs to be explored. Here, we isolated endophytes from different parts of W. somnifera plants and their promising role in in planta withanolide biosynthesis was established in both in-vivo grown as well in in-vitro raised composite W. somnifera plants. Overall, the fungal endophytes improved photosynthesis, plant growth and biomass, and the root-associated bacterial endophytes enhanced the withanolide content in both in-vivo and in-vitro grown plants by modulating the expression of withanolide biosynthesis genes in leaves and roots. Surprisingly, a few indole-3-acetic acid (IAA)-producing and nitrogen-fixing root-associated endophytes could induce the biosynthesis of withaferin-A in roots by inducing in planta IAA-production and upregulating the expression of withanolide biosynthesis genes especially MEP-pathway genes (DXS and DXR) in roots as well. Results indicate the role of endophytes in modulating the synthesis and site of withanolides production and the selected endophytes can be used for enhancing the in planta withanolide production and enriching roots with pharmaceutically important withaferin-A which is generally absent in roots.},
}
@article {pmid29581066,
year = {2018},
author = {Slullitel, PA and Buttaro, MA and Greco, G and Oñativia, JI and Sánchez, ML and Mc Loughlin, S and García-Ávila, C and Comba, F and Zanotti, G and Piccaluga, F},
title = {No lower bacterial adhesion for ceramics compared to other biomaterials: An in vitro analysis.},
journal = {Orthopaedics &amp; traumatology, surgery &amp; research : OTSR},
volume = {104},
number = {4},
pages = {439-443},
doi = {10.1016/j.otsr.2018.03.003},
pmid = {29581066},
issn = {1877-0568},
mesh = {Antibiosis ; *Bacterial Adhesion ; *Biocompatible Materials ; *Ceramics ; Chromium ; Cobalt ; Escherichia coli/physiology ; Joint Prosthesis/microbiology ; *Metals ; *Polyethylene ; Pseudomonas aeruginosa/physiology ; Staphylococcus aureus/physiology ; Staphylococcus epidermidis/physiology ; Symbiosis ; Titanium ; },
abstract = {BACKGROUND: Although there is some clinical evidence of ceramic bearings being associated with a lower infection rate after total hip arthroplasty (THA), available data remains controversial since this surface is usually reserved for young, healthy patients. Therefore, we investigated the influence of five commonly used biomaterials on the adhesion potential of four biofilm-producing bacteria usually detected in infected THAs.<br><br>HYPOTHESIS: Ceramic biomaterials exhibit less bacterial adherence than other biomaterials.<br><br>MATERIAL AND METHODS: In this in vitro research, we evaluated the ability of Staphylococcus aureus, Staphylococcus epidermidis ATCC 35984, Escherichia coli ATCC 25922 and Pseudomonas aeruginosa to adhere to the surface of a cobalt-chromium metal head, a fourth-generation ceramic head, a fourth-generation ceramic insert, a highly-crossed linked polyethylene insert and a titanium porous-coated acetabular component. After an initial washing step, bacterial separation from the surface of each specimen was done with a vortex agitator. The colony-forming units were counted to determine the number of viable adherent bacteria.<br><br>RESULTS: We found no differences on global bacterial adhesion between the different surfaces (p=0.5). E. coli presented the least adherence potential among the analysed pathogens (p<0.001). The combination of E. coli and S. epidermidis generated an antagonist effect over the adherence potential of S. epidermidis individually (58±4% vs. 48±5%; p=0.007). The combination of P. aeruginosa and S. aureus presented a trend to an increased adherence of P. aeruginosa independently, suggesting an agonist effect (71% vs. 62%; p=0.07).<br><br>DISCUSSION: Ceramic bearings appeared not to be related to a lower bacterial adhesion than other biomaterials. However, different adhesive potentials among bacteria may play a major role on infection's inception.<br><br>LEVEL OF EVIDENCE: IV, in vitro study.},
}
@article {pmid31585988,
year = {2019},
author = {Takeshita, K and Yamada, T and Kawahara, Y and Narihiro, T and Ito, M and Kamagata, Y and Shinzato, N},
title = {Tripartite Symbiosis of an Anaerobic Scuticociliate with two Hydrogenosome-Associated Endosymbionts, a Holospora-related Alphaproteobacterium and a Methanogenic Archaeon.},
journal = {Applied and environmental microbiology},
volume = {},
number = {},
pages = {},
doi = {10.1128/AEM.00854-19},
pmid = {31585988},
issn = {1098-5336},
abstract = {A number of anaerobic ciliates, unicellular eukaryote, intracellularly possess methanogenic archaea and bacteria as symbiotic partners. Although this tripartite relationship is of interest in terms of the fact that each participant is from three different domains, the difficulty in culture and maintenance of those host species with symbiotic partners has disturbed both ecological and functional studies so far. In this study, we obtained a stable culture of a small anaerobic scuticociliate, strain GW7. By transmission electron microscopic observation and fluorescent in situ hybridization with domain-specific probes, we demonstrated that GW7 possessed both archaeal and bacterial endosymbionts in its cytoplasm. These endosymbionts were independently associated with hydrogenosomes, which are organelle producing hydrogen and ATP in anaerobic condition. Clone library analyses targeting prokaryotic 16S rRNA genes, fluorescent in situ hybridization with endosymbiont-specific probes, and molecular phylogenetic analyses revealed phylogenetic affiliation and intracellular localization of these endosymbionts. The endosymbiotic archaeon is a methanogen belonging to the genus Methanoregula (order Methanomicrobiales); a member of this genus has been previously described as the endosymbiont of an anaerobic ciliate from the genus Metopus (class Armophorea), which is only distantly related to strain GW7 (class Oligohymenophorea). The endosymbiotic bacterium belongs to the family Holosporaceae of the class Alphaproteobacteria, which also comprises several endosymbionts of various aerobic ciliates. For this endosymbiotic bacterium, we proposed the novel candidate species in the novel candidate genus &quot;Candidatus Hydrogenosomobacter endosymbioticus.&quot;Importance Tripartite symbioses between anaerobic ciliated protists and their intracellular archaeal and bacterial symbionts are not uncommon, but most reports have been based mainly on microscopic observations. Deeper insights into the function, ecology, and evolution of these fascinating symbioses involving partners from all three domains of life have been hampered by the difficulties of culturing anaerobic ciliates in the laboratory and the frequent loss of their prokaryotic partners during long-term cultivation. In the present study, we report the isolation of an anaerobic scuticociliate, strain GW7, which has been stably maintained in our laboratory for more than three years without losing either of its endosymbionts. Unexpectedly, molecular characterization of the endosymbionts revealed that bacterial partner of GW7 is phylogenetically related to intranuclear endosymbionts of aerobic ciliates. This strain will enable future genomic, transcriptomic, and proteomic analyses of the interactions in this tripartite symbiosis and a comparison with the endosymbioses in aerobic ciliates.},
}
@article {pmid31585231,
year = {2019},
author = {Kudryavtsev, A and Volkova, E and Plotnikov, A},
title = {Vannella samoroda n. sp. (Amoebozoa) - First member of the genus from a continental saline habitat placed in a molecular tree.},
journal = {European journal of protistology},
volume = {71},
number = {},
pages = {125634},
doi = {10.1016/j.ejop.2019.125634},
pmid = {31585231},
issn = {1618-0429},
abstract = {Vannella samoroda n. sp. (Amoebozoa, Vannellida) was isolated from the mouth of the Malaya Samoroda river flowing into Elton, the largest European hypersaline lake (Russia). Among all rivers of the area, it has the highest salt content (ca. 110‰). Amoebae maintained in seawater medium with ca. 77‰ salts concentration had a set of morphological characters typical of Vannella spp.: rounded, fan-shaped, or spatulate locomotive form, floating form with bent, blunt-ended hyaline pseudopodia, and a cell coat consisting of regularly packed palisade elements and scarce simple filaments. Phylogenetic analyses based on SSU rRNA and cytochrome C oxidase subunit 1 genes show that the amoeba is most closely related to Vannella ebro Smirnov, 2001, but represents a distinct species. The clade of V. ebro and V. samoroda branches among marine species of Vannella. The studied species is the first member of the genus Vannella from a continental saline habitat described using molecular data. Interestingly, it has a broad range of salinity tolerance: cells reproduce above 18‰, while survival of a few cells regularly occurs even in highly diluted Prescott and James medium. The normal culture restores itself when PJ medium is substituted with 77‰ seawater medium even after months of experimental incubation.},
}
@article {pmid31583109,
year = {2019},
author = {La Carpia, F and Wojczyk, BS and Annavajhala, MK and Rebbaa, A and Culp-Hill, R and D'Alessandro, A and Freedberg, DE and Uhlemann, AC and Hod, EA},
title = {Transfusional iron overload and intravenous iron infusions modify the mouse gut microbiota similarly to dietary iron.},
journal = {NPJ biofilms and microbiomes},
volume = {5},
number = {},
pages = {26},
doi = {10.1038/s41522-019-0097-2},
pmid = {31583109},
issn = {2055-5008},
abstract = {Iron is essential for both microorganisms and their hosts. Although effects of dietary iron on gut microbiota have been described, the effect of systemic iron administration has yet to be explored. Here, we show that dietary iron, intravenous iron administration, and chronic transfusion in mice increase the availability of iron in the gut. These iron interventions have consistent and reproducible effects on the murine gut microbiota; specifically, relative abundance of the Parabacteroides and Lactobacillus genera negatively correlate with increased iron stores, whereas members of the Clostridia class positively correlate with iron stores regardless of the route of iron administration. Iron levels also affected microbial metabolites, in general, and indoles, in particular, circulating in host plasma and in stool pellets. Taken together, these results suggest that by shifting the balance of the microbiota, clinical interventions that affect iron status have the potential to alter biologically relevant microbial metabolites in the host.},
}
@article {pmid31582561,
year = {2019},
author = {Su, Z and Kuscu, C and Malik, A and Shibata, E and Dutta, A},
title = {Angiogenin generates specific stress-induced tRNA halves and is not involved in tRF-3-mediated gene silencing.},
journal = {The Journal of biological chemistry},
volume = {},
number = {},
pages = {},
doi = {10.1074/jbc.RA119.009272},
pmid = {31582561},
issn = {1083-351X},
abstract = {tRNA fragments (tRFs) and tRNA halves have been implicated in various cellular processes, including gene silencing, translation, stress granule assembly, cell differentiation, retrotransposon activity, symbiosis, apoptosis and more. Overexpressed angiogenin (ANG) cleaves tRNA anticodons and produces tRNA halves similar to those produced in response to stress. However, it is not clear whether endogenous ANG is essential for producing the stress-induced tRNA halves. It is also not clear whether smaller tRFs are generated from the tRNA halves. Here, using global short RNA-Seq approach, we found that ANG overexpression selectively cleaves a subset of tRNAs, including tRNAGlu, tRNAGly, tRNALys, tRNAVal, tRNAHis, tRNAAsp, and tRNASeC to produce tRNA halves and tRF-5s that are 26-30 bases long. Surprisingly, ANG knockout revealed that the majority of stress-induced tRNA halves, except for the 5' half from tRNAHisGTG and the 3' half from tRNAAspGTC, are ANG independent, suggesting there are other RNases that produce tRNA halves. We also found that the 17-25-bases-long tRF-3s and tRF-5s that could enter into Argonaute complexes are not induced by ANG overexpression, suggesting that they are generated independently from tRNA halves. Consistent with this, ANG knockout did not decrease tRF-3 levels or gene-silencing activity. We conclude that ANG cleaves specific tRNAs and is not the only RNAse that creates tRNA halves and that the shorter tRFs are not generated from the tRNA halves or from independent tRNA cleavage by ANG.},
}
@article {pmid31581628,
year = {2019},
author = {Mazzocca, A},
title = {The Systemic-Evolutionary Theory of the Origin of Cancer (SETOC): A New Interpretative Model of Cancer as a Complex Biological System.},
journal = {International journal of molecular sciences},
volume = {20},
number = {19},
pages = {},
doi = {10.3390/ijms20194885},
pmid = {31581628},
issn = {1422-0067},
abstract = {The Systemic-Evolutionary Theory of Cancer (SETOC) is a recently proposed theory based on two important concepts: (i) Evolution, understood as a process of cooperation and symbiosis (Margulian-like), and (ii) The system, in terms of the integration of the various cellular components, so that the whole is greater than the sum of the parts, as in any complex system. The SETOC posits that cancer is generated by the de-emergence of the &quot;eukaryotic cell system&quot; and by the re-emergence of cellular subsystems such as archaea-like (genetic information) and/or prokaryotic-like (mitochondria) subsystems, featuring uncoordinated behaviors. One of the consequences is a sort of &quot;cellular regression&quot; towards ancestral or atavistic biological functions or behaviors similar to those of protists or unicellular organisms in general. This de-emergence is caused by the progressive breakdown of the endosymbiotic cellular subsystem integration (mainly, information = nucleus and energy = mitochondria) as a consequence of long-term injuries. Known cancer-promoting factors, including inflammation, chronic fibrosis, and chronic degenerative processes, cause prolonged damage that leads to the breakdown or failure of this form of integration/endosymbiosis. In normal cells, the cellular &quot;subsystems&quot; must be fully integrated in order to maintain the differentiated state, and this integration is ensured by a constant energy intake. In contrast, when organ or tissue damage occurs, the constant energy intake declines, leading, over time, to energy shortage, failure of endosymbiosis, and the de-differentiated state observed in dysplasia and cancer.},
}
@article {pmid31581056,
year = {2019},
author = {Dias, AS and Almeida, CR and Helguero, LA and Duarte, IF},
title = {Metabolic crosstalk in the breast cancer microenvironment.},
journal = {European journal of cancer (Oxford, England : 1990)},
volume = {121},
number = {},
pages = {154-171},
doi = {10.1016/j.ejca.2019.09.002},
pmid = {31581056},
issn = {1879-0852},
abstract = {During tumorigenesis, breast tumour cells undergo metabolic reprogramming, which generally includes enhanced glycolysis, tricarboxylic acid cycle activity, glutaminolysis and fatty acid biosynthesis. However, the extension and functional importance of these metabolic alterations may diverge not only according to breast cancer subtypes, but also depending on the interaction of cancer cells with the complex surrounding microenvironment. This microenvironment comprises a variety of non-cancerous cells, such as immune cells (e.g. macrophages, lymphocytes, natural killer cells), fibroblasts, adipocytes and endothelial cells, together with extracellular matrix components and soluble factors, which influence cancer progression and are predictive of clinical outcome. The continuous interaction between cancer and stromal cells results in metabolic competition and symbiosis, with oncogenic-driven metabolic reprogramming of cancer cells shaping the metabolism of neighbouring cells and vice versa. This review addresses current knowledge on this metabolic crosstalk within the breast tumour microenvironment (TME). Improved understanding of how metabolism in the TME modulates cancer development and evasion of tumour-suppressive mechanisms may provide clues for novel anticancer therapeutics directed to metabolic targets.},
}
@article {pmid31574908,
year = {2019},
author = {Xi, P and Wang, D and Liu, W and Shi, C},
title = {DFT Study into the Influence of Carbon Material on the Hydrophobicity of a Coal Pyrite Surface.},
journal = {Molecules (Basel, Switzerland)},
volume = {24},
number = {19},
pages = {},
doi = {10.3390/molecules24193534},
pmid = {31574908},
issn = {1420-3049},
support = {3142017102//the Fundamental Research Funds for the Central Universities of China/ ; },
abstract = {From the macroscopic point of view, the hydrophilicity of symbiotic carbon pyrite is weakened overall compared to that of pure pyrite. It is very important to explain the impact of elemental carbon accreted on a pyrite surface on the surface's hydrophobicity from the perspective of quantum chemistry. To study the influence of adsorbed carbon atoms on the hydrophilicity of a coal pyrite surface versus a pyrite surface, the adsorption of a single water molecule at an adjacent Fe site of a one-carbon-atom-covered pyrite surface and a carbon atom monolayer were simulated and calculated with the first-principles method of density functional theory (DFT). The water molecules can be stably adsorbed at the adjacent Fe site of the carbon-atom-covered pyrite surface. The hybridization of the O 2p (H2O) and Fe 3d (pyrite surface) orbitals was the main interaction between the water molecule and the pyrite surface, forming a strong Fe-O covalent bond. The water molecule only slightly adsorbs above a C atom on the carbon-atom-covered pyrite and the carbon atom monolayer surfaces. The valence bond between the water molecule and the pyrite surface changed from an Fe-O bond to an Fe-C-O bond, in which the C-O bond is very weak, resulting in a weaker interaction between water and the surface.},
}
@article {pmid31571583,
year = {2019},
author = {Baker, LJ and Freed, LL and Easson, CG and Lopez, JV and Fenolio, D and Sutton, TT and Nyholm, SV and Hendry, TA},
title = {Diverse deep-sea anglerfishes share a genetically reduced luminous symbiont that is acquired from the environment.},
journal = {eLife},
volume = {8},
number = {},
pages = {},
doi = {10.7554/eLife.47606},
pmid = {31571583},
issn = {2050-084X},
abstract = {Deep-sea anglerfishes are relatively abundant and diverse, but their luminescent bacterial symbionts remain enigmatic. The genomes of two symbiont species have qualities common to vertically transmitted, host-dependent bacteria. However, a number of traits suggest that these symbionts may be environmentally acquired. To determine how anglerfish symbionts are transmitted, we analyzed bacteria-host codivergence across six diverse anglerfish genera. Most of the anglerfish species surveyed shared a common species of symbiont. Only one other symbiont species was found, which had a specific relationship with one anglerfish species, Cryptopsaras couesii. Host and symbiont phylogenies lacked congruence, and there was no statistical support for codivergence broadly. We also recovered symbiont-specific gene sequences from water collected near hosts, suggesting environmental persistence of symbionts. Based on these results we conclude that diverse anglerfishes share symbionts that are acquired from the environment, and that these bacteria have undergone extreme genome reduction although they are not vertically transmitted.},
}
@article {pmid30904352,
year = {2019},
author = {Zhang, YJ and Han, Y and Sun, YZ and Jiang, HH and Liu, M and Qi, RQ and Gao, XH},
title = {Extracellular vesicles derived from Malassezia furfur stimulate IL-6 production in keratinocytes as demonstrated in in vitro and in vivo models.},
journal = {Journal of dermatological science},
volume = {93},
number = {3},
pages = {168-175},
doi = {10.1016/j.jdermsci.2019.03.001},
pmid = {30904352},
issn = {1873-569X},
mesh = {Animals ; Cell Line ; Dermatitis/*immunology/microbiology/pathology ; Disease Models, Animal ; Extracellular Vesicles/*immunology ; Female ; Humans ; Interleukin-6/immunology/*metabolism ; Keratinocytes/*immunology/metabolism ; Malassezia/cytology/*immunology ; Mice ; Mice, Inbred BALB C ; NF-kappa B/immunology/metabolism ; Skin/cytology/immunology/microbiology ; Symbiosis ; },
abstract = {BACKGROUND: Malassezia is one of the commensal microorganisms colonized on human skin and has been shown to be related to several inflammatory cutaneous disorders. Previous studies indicated that Malassezia. sympodialis (M. sympodialis) can produce extracellular vesicles, however, the immunoregulatory function of Malassezia extracellular vesicles on keratinocytes has not been studied.<br><br>OBJECTIVE: To investigate the extracellular vesicular production capability of Malassezia. furfur (M. furfur) and examine their immunoregulatory effects both in vitro and in vivo.<br><br>METHODS: Extracellular vesicles derived from M. furfur were isolated by sequential ultracentrifugation procedure. Their structure and diameter were determined by negative stain TEM and NTA, respectively. Confocal microscopy was used to visualize the internalization of these nanoparticles into HaCaT cells and mice epidermal keratinocytes. The expressions of inflammatory cytokines were screened using PCR Array assay and validated in vitro by qPCR and ELISA assays. In vivo cytokine production was measured by the IHC method. The role of NF-κB in such process was evaluated in HaCaT cells by western blot assay.<br><br>RESULTS: Our results showed that M. furfur produced ovoid-shaped nanoparticles, which could be then internalized into HaCaT cells, as well as mice epidermal keratinocytes. IL-6 expression was significantly enhanced in response to extracellular vesicular stimulation both in vitro and in vivo, in which process the activation of NF-κB was involved.<br><br>CONCLUSION: M. furfur has the ability to release extracellular vesicles, which can be internalized into keratinocytes and promote the production of IL-6 with the involvement of NF-κB dependent pathway. Such findings reveal some important new insights into Malassezia pathogenesis and therapy.},
}
@article {pmid30205029,
year = {2018},
author = {Nuismer, SL and Week, B and Aizen, MA},
title = {Coevolution Slows the Disassembly of Mutualistic Networks.},
journal = {The American naturalist},
volume = {192},
number = {4},
pages = {490-502},
doi = {10.1086/699218},
pmid = {30205029},
issn = {1537-5323},
mesh = {Animals ; *Biological Evolution ; Biota ; Computer Simulation ; Human Activities ; Models, Theoretical ; Plants ; *Symbiosis ; },
abstract = {Important groups of mutualistic species are threatened worldwide, and identifying factors that make them more or less fragile in the face of disturbance is becoming increasingly critical. Although much research has focused on identifying the ecological factors that favor the stability of communities rich in mutualists, much less has been devoted to understanding the role played by historical and contemporary evolution. Here we develop mathematical models and computer simulations of coevolving mutualistic communities that allow us to explore the importance of coevolution in stabilizing communities against anthropogenic disturbance. Our results demonstrate that communities with a long history of coevolution are substantially more robust to disturbance, losing individual species and interactions at lower rates. In addition, our results identify a novel phenomenon-coevolutionary rescue-that mitigates the impacts of ongoing anthropogenic disturbance by rewiring the network structure of the community in a way that compensates for the extinction of individual species and interactions.},
}
@article {pmid30146006,
year = {2018},
author = {Huang, C and Wang, J and Zheng, X and Chen, Y and Zhou, R and Wei, H and Sun, R and Tian, Z},
title = {Commensal bacteria aggravate allergic asthma via NLRP3/IL-1β signaling in post-weaning mice.},
journal = {Journal of autoimmunity},
volume = {93},
number = {},
pages = {104-113},
doi = {10.1016/j.jaut.2018.07.003},
pmid = {30146006},
issn = {1095-9157},
mesh = {Animals ; Animals, Newborn ; Anti-Bacterial Agents/pharmacology ; Asthma/chemically induced/genetics/immunology/*microbiology ; Bronchoalveolar Lavage Fluid/chemistry/cytology/immunology ; Disease Models, Animal ; Epithelial Cells/drug effects/immunology/pathology ; Gene Expression ; Interleukin-1beta/genetics/*immunology ; Lung/drug effects/*immunology/microbiology ; Macrophages, Peritoneal/drug effects/immunology/pathology ; Metronidazole/pharmacology ; Mice ; Mice, Inbred C57BL ; Mice, Knockout ; Microbiota/immunology ; NLR Family, Pyrin Domain-Containing 3 Protein/genetics/*immunology ; Ovalbumin/administration &amp; dosage ; Signal Transduction/*immunology ; Symbiosis/*immunology ; Vancomycin/pharmacology ; Weaning ; },
abstract = {Perturbation of commensal bacteria by antibiotic exposure aggravates ovalbumin (OVA)-induced allergic asthma in pre-weaning mice. However, the influence of dysbiosis of commensal bacteria on asthma development in post-weaning mice is still limited. Here, we treated 3-week-old post-weaning mice with antibiotics to disrupt commensal bacteria and then established OVA-induced allergic asthma by peritoneal sensitization using OVA/alum and intranasal challenge with OVA. Contrary to the protective function in pre-weaning mice, commensal bacteria in post-weaning mice aggravated OVA-induced asthma. Commensal bacteria in post-weaning mice promoted OVA-induced allergic asthma through maintenance of NLRP3/IL-1β expression in peritoneal macrophages (pMφ), which promoted recruitment of inflammatory cells, especially inflammatory monocytes, into the peritoneal cavity after OVA/alum sensitization. Further study showed that metronidazole- and vancomycin-sensitive bacteria are involved in maintenance of NLRP3/IL-1β signal in pMφ. Our results suggest that certain species of commensal bacteria in post-weaning mice aggravate OVA-induced allergic asthma through NLRP3/IL-1β signal pathway.},
}
@article {pmid29934134,
year = {2018},
author = {Zaheer, M and Wang, C and Bian, F and Yu, Z and Hernandez, H and de Souza, RG and Simmons, KT and Schady, D and Swennes, AG and Pflugfelder, SC and Britton, RA and de Paiva, CS},
title = {Protective role of commensal bacteria in Sjögren Syndrome.},
journal = {Journal of autoimmunity},
volume = {93},
number = {},
pages = {45-56},
pmid = {29934134},
issn = {1095-9157},
support = {P30 CA125123/CA/NCI NIH HHS/United States ; P30 DK056338/DK/NIDDK NIH HHS/United States ; T32 AI053831/AI/NIAID NIH HHS/United States ; S10 RR024574/RR/NCRR NIH HHS/United States ; P30 AI036211/AI/NIAID NIH HHS/United States ; R01 EY026893/EY/NEI NIH HHS/United States ; },
mesh = {Animals ; CD4-Positive T-Lymphocytes/immunology/pathology ; Cornea/*immunology/pathology ; Dacryocystitis/genetics/immunology/*microbiology/pathology ; Disease Models, Animal ; Fecal Microbiota Transplantation ; Female ; Gastrointestinal Microbiome/immunology ; Gene Expression Regulation ; Germ-Free Life ; Goblet Cells/immunology/pathology ; Homeodomain Proteins/genetics/*immunology ; Interferon-gamma/genetics/immunology ; Interleukin-12/genetics/immunology ; Interleukin-2 Receptor alpha Subunit/deficiency/genetics/*immunology ; Lacrimal Apparatus/*immunology/pathology ; Mice ; Mice, Inbred C57BL ; Mice, Knockout ; Permeability ; Sjogren's Syndrome/genetics/immunology/*microbiology/pathology ; Symbiosis/*immunology ; },
abstract = {CD25 knock-out (CD25KO) mice spontaneously develop Sjögren Syndrome (SS)-like inflammation. We investigated the role of commensal bacteria by comparing CD25KO mice housed in conventional or germ-free conditions. Germ-free CD25KO mice have greater corneal barrier dysfunction, lower goblet cell density, increased total lymphocytic infiltration score, increased expression of IFN-γ, IL-12 and higher a frequency of CD4+IFN-γ+ cells than conventional mice. CD4+ T cells isolated from female germ-free CD25KO mice adoptively transferred to naive immunodeficient RAG1KO recipients caused more severe Sjögren-like disease than CD4+ T cells transferred from conventional CD25KO mice. Fecal transplant in germ-free CD25KO mice reversed the spontaneous dry eye phenotype and decreased the generation of pathogenic CD4+IFN-γ+ cells. Our studies indicate that lack of commensal bacteria accelerates the onset and severity of dacryoadenitis and generates autoreactive CD4+T cells with greater pathogenicity in the CD25KO model, suggesting that the commensal bacteria or their metabolites products have immunoregulatory properties that protect exocrine glands in the CD25KO SS model.},
}
@article {pmid29675831,
year = {2018},
author = {Kauko, A and Lehto, K},
title = {Eukaryote specific folds: Part of the whole.},
journal = {Proteins},
volume = {86},
number = {8},
pages = {868-881},
doi = {10.1002/prot.25517},
pmid = {29675831},
issn = {1097-0134},
mesh = {Archaea/genetics ; Bacteria/classification ; Biological Evolution ; Databases, Protein ; Eukaryota/*classification ; Eukaryotic Cells/classification ; Evolution, Molecular ; Genes, Bacterial ; Genes, Mitochondrial ; Mitochondria/genetics ; Phylogeny ; Proteins/genetics ; Symbiosis/*genetics ; },
abstract = {The origin of eukaryotes is one of the central transitions in the history of life; without eukaryotes there would be no complex multicellular life. The most accepted scenarios suggest the endosymbiosis of a mitochondrial ancestor with a complex archaeon, even though the details regarding the host and the triggering factors are still being discussed. Accordingly, phylogenetic analyses have demonstrated archaeal affiliations with key informational systems, while metabolic genes are often related to bacteria, mostly to the mitochondrial ancestor. Despite of this, there exists a large number of protein families and folds found only in eukaryotes. In this study, we have analyzed structural superfamilies and folds that probably appeared during eukaryogenesis. These folds typically represent relatively small binding domains of larger multidomain proteins. They are commonly involved in biological processes that are particularly complex in eukaryotes, such as signaling, trafficking/cytoskeleton, ubiquitination, transcription and RNA processing, but according to recent studies, these processes also have prokaryotic roots. Thus the folds originating from an eukaryotic stem seem to represent accessory parts that have contributed in the expansion of several prokaryotic processes to a new level of complexity. This might have taken place as a co-evolutionary process where increasing complexity and fold innovations have supported each other.},
}
@article {pmid29574753,
year = {2018},
author = {Lu, KJ and Danila, FR and Cho, Y and Faulkner, C},
title = {Peeking at a plant through the holes in the wall - exploring the roles of plasmodesmata.},
journal = {The New phytologist},
volume = {218},
number = {4},
pages = {1310-1314},
doi = {10.1111/nph.15130},
pmid = {29574753},
issn = {1469-8137},
mesh = {Calcium Signaling ; Cell Wall/*physiology ; Circadian Clocks ; Genome, Plant ; Plasmodesmata/*physiology ; Symbiosis ; },
abstract = {Plasmodesmata (PD) are membrane-lined pores that connect neighbouring plant cells and allow molecular exchange via the symplast. Past studies have revealed the basic structure of PD, some of the transport mechanisms for molecules through PD, and a variety of physiological processes in which they function. Recently, with the help of newly developed technologies, several exciting new features of PD have been revealed. New PD structures were observed during early formation of PD and between phloem sieve elements and phloem pole pericycle cells in roots. Both observations challenge our current understanding of PD structure and function. Research into novel physiological responses, which are regulated by PD, indicates that we have not yet fully explored the potential contribution of PD to overall plant function. In this Viewpoint article, we summarize some of the recent advances in understanding the structure and function of PD and propose the challenges ahead for the community.},
}
@article {pmid31568958,
year = {2019},
author = {Sebastiana, M and Duarte, B and Monteiro, F and Malhó, R and Caçador, I and Matos, AR},
title = {The leaf lipid composition of ectomycorrhizal oak plants shows a drought-tolerance signature.},
journal = {Plant physiology and biochemistry : PPB},
volume = {144},
number = {},
pages = {157-165},
doi = {10.1016/j.plaphy.2019.09.032},
pmid = {31568958},
issn = {1873-2690},
abstract = {Ectomycorrhizas have been reported to increase plant tolerance to drought. However, the mechanisms involved are not yet fully understood. Membranes are the first targets of degradation during drought, and growing evidences support a role for membrane lipids in plant tolerance and adaptation to drought. We have previously shown that improved tolerance of ectomycorrhizal oak plants to drought could be related to leaf membrane lipid metabolism, namely through an increased ability to sustain fatty acid content and composition, indicative of a higher membrane stability under stress. Here, we analysed in deeper detail the modulation of leaf lipid metabolism in oak plants mycorrhized with Pisolithus tinctorius and subjected to drought stress. Results show that mycorrhizal plants show patterns associated with water deficit tolerance, like a higher content of chloroplast lipids, whose levels are maintained upon drought stress. Likewise, mycorrhizal plants show increased levels of unsaturated fatty acids in the chloroplast phosphatidylglycerol lipid fraction. As a common response to drought, the digalactosyldiacyloglycerol/monogalactosyldiacyloglycerol ratio increased in the non-mycorrhizal plants, but not in the mycorrhizal plants, associated to smaller alterations in the expression of galactolipid metabolism genes, indicative of a higher drought tolerance. Under drought, inoculated plants showed increased expression of genes involved in neutral lipids biosynthesis, which could be related to an increased ability to tolerate drought stress. Overall, results from this study provide evidences of the involvement of lipid metabolism in the response of ectomycorrhizal plants to water deficit and point to an increased ability to maintain a stable chloroplast membrane functional integrity under stress.},
}
@article {pmid31568486,
year = {2019},
author = {Voronin, D and Schnall, E and Grote, A and Jawahar, S and Ali, W and Unnasch, TR and Ghedin, E and Lustigman, S},
title = {Pyruvate produced by Brugia spp. via glycolysis is essential for maintaining the mutualistic association between the parasite and its endosymbiont, Wolbachia.},
journal = {PLoS pathogens},
volume = {15},
number = {9},
pages = {e1008085},
doi = {10.1371/journal.ppat.1008085},
pmid = {31568486},
issn = {1553-7374},
abstract = {Human parasitic nematodes are the causative agents of lymphatic filariasis (elephantiasis) and onchocerciasis (river blindness), diseases that are endemic to more than 80 countries and that consistently rank in the top ten for the highest number of years lived with disability. These filarial nematodes have evolved an obligate mutualistic association with an intracellular bacterium, Wolbachia, a symbiont that is essential for the successful development, reproduction, and survival of adult filarial worms. Elimination of the bacteria causes adult worms to die, making Wolbachia a primary target for developing new interventional tools to combat filariases. To further explore Wolbachia as a promising indirect macrofilaricidal drug target, the essential cellular processes that define the symbiotic Wolbachia-host interactions need to be identified. Genomic analyses revealed that while filarial nematodes encode all the enzymes necessary for glycolysis, Wolbachia does not encode the genes for three glycolytic enzymes: hexokinase, 6-phosphofructokinase, and pyruvate kinase. These enzymes are necessary for converting glucose into pyruvate. Wolbachia, however, has the full complement of genes required for gluconeogenesis starting with pyruvate, and for energy metabolism via the tricarboxylic acid cycle. Therefore, we hypothesized that Wolbachia might depend on host glycolysis to maintain a mutualistic association with their parasitic host. We did conditional experiments in vitro that confirmed that glycolysis and its end-product, pyruvate, sustain this symbiotic relationship. Analysis of alternative sources of pyruvate within the worm indicated that the filarial lactate dehydrogenase could also regulate the local intracellular concentration of pyruvate in proximity to Wolbachia and thus help control bacterial growth via molecular interactions with the bacteria. Lastly, we have shown that the parasite's pyruvate kinase, the enzyme that performs the last step in glycolysis, could be a potential novel anti-filarial drug target. Establishing that glycolysis is an essential component of symbiosis in filarial worms could have a broader impact on research focused on other intracellular bacteria-host interactions where the role of glycolysis in supporting intracellular survival of bacteria has been reported.},
}
@article {pmid31565856,
year = {2019},
author = {Gilbert, SF},
title = {Evolutionary transitions revisited: Holobiont evo-devo.},
journal = {Journal of experimental zoology. Part B, Molecular and developmental evolution},
volume = {},
number = {},
pages = {},
doi = {10.1002/jez.b.22903},
pmid = {31565856},
issn = {1552-5015},
support = {//Swarthmore College Faculty Research Grant/ ; },
abstract = {John T. Bonner lists four essential transformations in the evolution of life: the emergence of the eukaryotic cell, meiosis, multicellularity, and the nervous system. This paper analyses the mechanisms for those transitions in light of three of Dr. Bonner's earlier hypotheses: (a) that the organism is its life cycle, (b) that evolution consists of alterations of the life cycle, and (c) that development extends beyond the body and into interactions with other organisms. Using the notion of the holobiont life cycle, this paper attempts to show that these evolutionary transitions can be accomplished through various means of symbiosis. Perceiving the organism both as an interspecies consortium and as a life cycle supports a twofold redefinition of the organism as a holobiont constructed by integrating together the life cycles of several species. These findings highlight the importance of symbiosis and the holobiont development in analyses of evolution.},
}
@article {pmid31564246,
year = {2019},
author = {Feng, H and Park, JS and Zhai, RG and Wilson, ACC},
title = {microRNA-92a regulates the expression of aphid bacteriocyte-specific secreted protein 1.},
journal = {BMC research notes},
volume = {12},
number = {1},
pages = {638},
doi = {10.1186/s13104-019-4665-6},
pmid = {31564246},
issn = {1756-0500},
support = {IOS-1121847//National Science Foundation/ ; IOS-354154//National Science Foundation/ ; R56NS095893//Foundation for the National Institutes of Health/ ; },
abstract = {OBJECTIVE: Aphids harbor a nutritional obligate endosymbiont in specialized cells called bacteriocytes, which aggregate to form an organ known as the bacteriome. Aphid bacteriomes display distinct gene expression profiles that facilitate the symbiotic relationship. Currently, the mechanisms that regulate these patterns of gene expression are unknown. Recently using computational pipelines, we identified miRNAs that are conserved in expression in the bacteriomes of two aphid species and proposed that they function as important regulators of bacteriocyte gene expression. Here using a dual luciferase assay in mouse NIH/3T3 cell culture, we aimed to experimentally validate the computationally predicted interaction between Myzus persicae miR-92a and the predicted target region of M. persicae bacteriocyte-specific secreted protein 1 (SP1) mRNA.<br><br>RESULTS: In the dual luciferase assay, miR-92a interacted with the SP1 target region resulting in a significant downregulation of the luciferase signal. Our results demonstrate that miR-92a interacts with SP1 to alter expression in a heterologous expression system, thereby supporting our earlier assertion that miRNAs are regulators of the aphid/Buchnera symbiotic interaction.},
}
@article {pmid30356736,
year = {2018},
author = {Vitetta, L and Vitetta, G and Hall, S},
title = {Immunological Tolerance and Function: Associations Between Intestinal Bacteria, Probiotics, Prebiotics, and Phages.},
journal = {Frontiers in immunology},
volume = {9},
number = {},
pages = {2240},
pmid = {30356736},
issn = {1664-3224},
mesh = {Bacteria/classification/*immunology ; Bacteriophages/classification/*immunology ; Gastrointestinal Microbiome/*immunology ; Humans ; Immune Tolerance/*immunology ; Intestines/*immunology/microbiology/virology ; Prebiotics/administration &amp; dosage ; Probiotics/administration &amp; dosage ; Symbiosis/immunology ; },
abstract = {Post-birth there is a bacterial assault on all mucosal surfaces. The intestinal microbiome is an important participant in health and disease. The pattern of composition and concentration of the intestinal microbiome varies greatly. Therefore, achieving immunological tolerance in the first 3-4 years of life is critical for maintaining health throughout a lifetime. Probiotic bacteria are organisms that afford beneficial health effects to the host and in certain instances may protect against the development of disease. The potential benefits of modifying the composition of the intestinal microbial cohort for therapeutic benefit is evident in the use in high risks groups such as premature infants, children receiving antibiotics, rotavirus infections in non-vaccinated children and traveler's diarrhea in adults. Probiotics and prebiotics are postulated to have immunomodulating capabilities by influencing the intestinal microbial cohort and dampening the activity of pathobiont intestinal microbes, such as Klebsiella pneumonia and Clostridia perfringens. Lactobacilli and Bifidobacteria are examples of probiotics found in the large intestine and so far, the benefits afforded to probiotics have varied in efficacy. Most likely the efficacy of probiotic bacteria has a multifactorial dependency, namely on a number of factors that include agents used, the dose, the pattern of dosing, and the characteristics of the host and the underlying luminal microbial environment and the activity of bacteriophages. Bacteriophages, are small viruses that infect and lyse intestinal bacteria. As such it can be posited that these viruses display an effective local protective control mechanism for the intestinal barrier against commensal pathobionts that indirectly may assist the host in controlling bacterial concentrations in the gut. A co-operative activity may be envisaged between the intestinal epithelia, mucosal immunity and the activity of bacteriophages to eliminate pathobiots, highlighting the potential role of bacteriophages in assisting with maintaining intestinal homeostasis. Hence bacteriophage local control of inflammation and immune responses may be an additional immunological defense mechanism that exploits bacteriophage-mucin glycoprotein interactions that controls bacterial diversity and abundance in the mucin layers of the gut. Moreover, and importantly the efficacy of probiotics may be dependent on the symbiotic incorporation of prebiotics, and the abundance and diversity of the intestinal microbiome encountered. The virome may be an important factor that determines the efficacy of some probiotic formulations.},
}
@article {pmid30283451,
year = {2018},
author = {Lange, A and Schäfer, A and Bender, A and Steimle, A and Beier, S and Parusel, R and Frick, JS},
title = {Galleria mellonella: A Novel Invertebrate Model to Distinguish Intestinal Symbionts From Pathobionts.},
journal = {Frontiers in immunology},
volume = {9},
number = {},
pages = {2114},
pmid = {30283451},
issn = {1664-3224},
mesh = {Animals ; Bacteria/immunology/pathogenicity ; Host-Pathogen Interactions/immunology ; Humans ; Immunity, Innate/*immunology ; Intestines/*immunology/parasitology ; Invertebrates/*immunology/physiology ; Mice ; Moths/*immunology/physiology ; Phylogeny ; Receptors, Pattern Recognition/immunology/metabolism ; Symbiosis/*immunology ; Virulence/immunology ; beta-Defensins/classification/genetics/immunology ; },
abstract = {Insects and mammals share evolutionary conserved innate immune responses to maintain intestinal homeostasis. We investigated whether the larvae of the greater wax moth Galleria mellonella may be used as an experimental organism to distinguish between symbiotic Bacteroides vulgatus and pathobiotic Escherichia coli, which are mammalian intestinal commensals. Oral application of the symbiont or pathobiont to G. mellonella resulted in clearly distinguishable innate immune responses that could be verified by analyzing similar innate immune components in mice in vivo and in vitro. The differential innate immune responses were initiated by the recognition of bacterial components via pattern recognition receptors. The pathobiont detection resulted in increased expression of reactive oxygen and nitrogen species related genes as well as antimicrobial peptide gene expression. In contrast, the treatment/application with symbiotic bacteria led to weakened immune responses in both mammalian and insect models. As symbionts and pathobionts play a crucial role in development of inflammatory bowel diseases, we hence suggest G. mellonella as a future replacement organism in inflammatory bowel disease research.},
}
@article {pmid30113119,
year = {2018},
author = {Niehs, SP and Dose, B and Scherlach, K and Roth, M and Hertweck, C},
title = {Genomics-Driven Discovery of a Symbiont-Specific Cyclopeptide from Bacteria Residing in the Rice Seedling Blight Fungus.},
journal = {Chembiochem : a European journal of chemical biology},
volume = {19},
number = {20},
pages = {2167-2172},
doi = {10.1002/cbic.201800400},
pmid = {30113119},
issn = {1439-7633},
mesh = {Burkholderia/classification/genetics/*metabolism ; Oryza/*microbiology ; Peptide Synthases/metabolism ; *Peptides, Cyclic/chemistry/genetics/metabolism ; Plant Diseases/*microbiology ; Rhizopus/*metabolism ; Seedlings/*microbiology ; Symbiosis ; },
abstract = {The rice seedling blight fungus Rhizopus microsporus harbors endosymbiotic bacteria (Burkholderia rhizoxinica) that produce the virulence factor rhizoxin and control host development. Genome mining indicated a massive inventory of cryptic nonribosomal peptide synthetase (NRPS) genes, which have not yet been linked to any natural products. The discovery and full characterization of a novel cyclopeptide from endofungal bacteria is reported. In silico analysis of an orphan, symbiont-specific NRPS predicted the structure of a nonribosomal peptide, which was targeted by LC-MS/MS profiling of wild-type and engineered null mutants. NMR spectroscopy and chemical derivatization elucidated the structure of the bacterial cyclopeptide. Phylogenetic analyses revealed the relationship of starter C domains for rare N-acetyl-capped peptides. Heptarhizin is produced under symbiotic conditions in geographically constrained strains from the Pacific clade; this indicates a potential ecological role of the peptide.},
}
@article {pmid29981324,
year = {2018},
author = {Arenas, A and Roces, F},
title = {Appetitive and aversive learning of plants odors inside different nest compartments by foraging leaf-cutting ants.},
journal = {Journal of insect physiology},
volume = {109},
number = {},
pages = {85-92},
doi = {10.1016/j.jinsphys.2018.07.001},
pmid = {29981324},
issn = {1879-1611},
mesh = {Animals ; Ants/*physiology ; Appetitive Behavior/*physiology ; Basidiomycota ; Learning/*physiology ; Nesting Behavior/physiology ; *Odorants ; Plants/chemistry ; Smell/physiology ; Symbiosis ; },
abstract = {Cues inside the nest provide social insect foragers with information about resources currently exploited that may influence their decisions outside. Leaf-cutting ants harvest leaf fragments that are either further processed as substrate for their symbiotic fungus, or disposed of if unsuitable. We investigated whether Acromyrmex ambiguus foragers develop learned preferences for olfactory cues they experienced either in the fungus or in the waste chamber of the nest. Foragers' olfactory preferences were quantified as a choice between sugared papers disks scented with a novel odor and with the odor experienced in one of the nest compartments, before and after odor addition. Odors incorporated in the fungus chamber led to preferences towards paper disks smelling of them. Conversely, odors experienced in the waste chambers led to avoidance of similarly-scented disks. To investigate context-specificity of responses, we quantified learned preferences towards an odor that occurred first in the fungus chamber, and 14 h later in the waste chamber. Foragers initially developed a preference for the odor added in the fungus chamber that turned into avoidance when the same odor solely occurred later in the waste chamber. Avoidance of plants could also be induced in a more natural context, when fresh leaf disks of novel plants, privet or firethorn, were presented in the waste chamber. We conclude that learned acceptance or rejection of suitable plants by foragers depend on the learning context: smells can lead to appetitive learning when present in the fungus garden, or to avoidance learning when they occur at the dump.},
}
@article {pmid29535321,
year = {2018},
author = {Onuț-Brännström, I and Benjamin, M and Scofield, DG and Heiðmarsson, S and Andersson, MGI and Lindström, ES and Johannesson, H},
title = {Sharing of photobionts in sympatric populations of Thamnolia and Cetraria lichens: evidence from high-throughput sequencing.},
journal = {Scientific reports},
volume = {8},
number = {1},
pages = {4406},
pmid = {29535321},
issn = {2045-2322},
mesh = {Ascomycota/classification/*physiology ; Biodiversity ; DNA, Ribosomal Spacer ; Ecosystem ; High-Throughput Nucleotide Sequencing ; Lichens/physiology ; Parmeliaceae/classification/*physiology ; Photosynthesis ; Phylogeny ; *Symbiosis ; },
abstract = {In this study, we explored the diversity of green algal symbionts (photobionts) in sympatric populations of the cosmopolitan lichen-forming fungi Thamnolia and Cetraria. We sequenced with both Sanger and Ion Torrent High-Throughput Sequencing technologies the photobiont ITS-region of 30 lichen thalli from two islands: Iceland and Öland. While Sanger recovered just one photobiont genotype from each thallus, the Ion Torrent data recovered 10-18 OTUs for each pool of 5 lichen thalli, suggesting that individual lichens can contain heterogeneous photobiont populations. Both methods showed evidence for photobiont sharing between Thamnolia and Cetraria on Iceland. In contrast, our data suggest that on Öland the two mycobionts associate with distinct photobiont communities, with few shared OTUs revealed by Ion Torrent sequencing. Furthermore, by comparing our sequences with public data, we identified closely related photobionts from geographically distant localities. Taken together, we suggest that the photobiont composition in Thamnolia and Cetraria results from both photobiont-mycobiont codispersal and local acquisition during mycobiont establishment and/or lichen growth. We hypothesize that this is a successful strategy for lichens to be flexible in the use of the most adapted photobiont for the environment.},
}
@article {pmid29377140,
year = {2018},
author = {Pozzi, AC and Roy, M and Nagati, M and Schwob, G and Manzi, S and Gardes, M and Moreau, PA and Fernandez, MP},
title = {Patterns of diversity, endemism and specialization in the root symbiont communities of alder species on the island of Corsica.},
journal = {The New phytologist},
volume = {219},
number = {1},
pages = {336-349},
doi = {10.1111/nph.14996},
pmid = {29377140},
issn = {1469-8137},
mesh = {Alnus/*microbiology ; *Biodiversity ; France ; Frankia/genetics/physiology ; Italy ; Mycorrhizae/physiology ; Phylogeny ; Plant Roots/*microbiology ; Root Nodules, Plant/microbiology ; Soil Microbiology ; Symbiosis/physiology ; },
abstract = {We investigated whether the diversity, endemicity and specificity of alder symbionts could be changed by isolation in a Mediterranean glacial refugium. We studied both ectomycorrhizal (EM) fungi and nitrogen-fixing actinobacteria associated with alders, and compared their communities in Corsica and on the European continent. Nodules and root tips were sampled on the three alder species present in Corsica and continental France and Italy. Phylogenies based on internal transcribed spacer (ITS) and a multilocus sequence analysis approach were used to characterize fungal and Frankia species, respectively. Patterns of diversity, endemism and specialization were compared between hosts and regions for each symbiont community. In Corsica, communities were not generally richer than on the mainland. The species richness per site depended mainly on host identity: Alnus glutinosa and Alnus cordata hosted richer Frankia and EM communities, respectively. Half of the Frankia species were endemic to Corsica against only 4% of EM species. Corsica is not a hotspot of diversity for all alder symbionts but sustains an increased frequency of poor-dispersers such as hypogeous fungi. Generalist EM fungi and host-dependent profusely sporulating (Sp+) Frankia were abundantly associated with Corsican A. cordata, a pattern related to a more thermophilic and xerophylic climate and to the co-occurrence with other host trees.},
}
@article {pmid31563584,
year = {2019},
author = {Cao, C and Li, H and Jones, MGK and Wylie, SJ},
title = {Challenges to elucidating how endornaviruses influence fungal hosts: creating mycovirus-free isogenic fungal lines and testing them.},
journal = {Journal of virological methods},
volume = {},
number = {},
pages = {113745},
doi = {10.1016/j.jviromet.2019.113745},
pmid = {31563584},
issn = {1879-0984},
abstract = {Determining roles of mycoviruses in fungal biology is complicated, especially when fungi are co-infected with multiple viruses. Genetically identical (isogenic) fungal lines that are infected by and uninfected by viruses must be created and compared. Here, we study an isolate of Ceratobasidium sp., a fungus isolated from pelotons in roots of a wild terrestrial orchid. The fungal isolate was co-infected with three distinct endornaviruses, isolates of Ceratobasidium endonarvirus B (CbEVB), Ceratobasidium endonarvirus C (CbEVC) and Ceratobasidium endonarvirus D (CbEVD). An experiment to reveal natural distribution of the three mycoviruses within a fungal colony revealed no sectoring; they were all evenly distributed throughout the colony. Hyphal tipping and treatments with one of five antibiotics (kanamycin, streptomycin, cycloheximide, rifampicin and ampicillin) were applied in attempts to 'cure' fungal lines of one, two or three of the viruses present. Surprisingly, the three mycoviruses responded differentially to each curing approach. The isolate of CbEVC was eliminated upon treatment with cycloheximide, but not with kanamycin or streptomycin, whereas the isolate of CbEVD did not respond to cycloheximide. The isolate of CbEVB was eliminated upon all treatments. In some cases, a virus was undetectable by RT-PCR after treatment, but when the fungus was cultured for a period on non-selective medium, the virus was detected again. Effects of mycoviruses on growth characteristics of isogenic fungal lines on two media were studied. Co-infection by the three viruses reduced mycelial growth rate on both media. In contrast, some fungal lines infected with one or two mycoviruses grew more rapidly than virus-free lines.},
}
@article {pmid31562172,
year = {2019},
author = {Speck, JJ and James, EK and Sugawara, M and Sadowsky, MJ and Gyaneshwar, P},
title = {An Alkane Sulfonate Monooxygenase is Required for Symbiotic Nitrogen Fixation by Bradyrhizobium diazoefficiens (syn. Bradyrhizobium japonicum) USDA110T.},
journal = {Applied and environmental microbiology},
volume = {},
number = {},
pages = {},
doi = {10.1128/AEM.01552-19},
pmid = {31562172},
issn = {1098-5336},
abstract = {Sulfur (S) containing molecules play an important role in symbiotic nitrogen fixation, and are critical components of nitrogenase and other iron-S proteins. S deficiency inhibits symbiotic nitrogen fixation by rhizobia. However, despite its importance, little is known about the sources of S that rhizobia utilize during symbiosis. We previously showed that Bradyrhizobium diazoefficiens USDA110T can assimilate both inorganic and organic S and that genes involved in organic S utilization are expressed during symbiosis. Here we show that a B. diazoefficiens USDA110 T insertion mutant in sulfonate monooxygenase (ssuD) is defective in nitrogen fixation. Microscopy analyses revealed that the ssuD- was defective in root hair infection and that bacteroids of the ssuD- showed degradation as compared to the wild type strain. Moreover, the ssuD- was significantly more sensitive to hydrogen peroxide-mediated oxidative stress than was the wild type strain. Taken together, these results show that the ability of rhizobia to utilize organic S plays an important role in symbiotic nitrogen fixation. Since nodules have been reported to be an important source of reduced S used during symbiosis and nitrogen fixation, further research will be needed to determine the mechanisms involved in regulation of S assimilation by rhizobia.IMPORTANCE Rhizobia form symbiotic association with legumes that lead to formation of nitrogen-fixing nodules. Sulfur-containing molecules play crucial role in nitrogen fixation and thus the rhizobia inside nodules require high amounts of sulfur. Rhizobia can assimilate both inorganic (sulfate) and organic (sulfonates) sources of sulfur. However, very little is known about rhizobial sulfur metabolism during symbiosis. In this report, we show that sulfonate utilization by Bradyrhizobium diazoefficiens is important for symbiotic nitrogen fixation in both soybean and cowpea. The symbiotic defect is probably due to increased sensitivity to oxidative stress from sulfur deficiency in the mutant strain defective for sulfonate utilization. The results of this study can be extended to other rhizobia-legume symbioses as sulfonate utilization genes are widespread in these bacteria.},
}
@article {pmid31561965,
year = {2019},
author = {Jahn, MT and Arkhipova, K and Markert, SM and Stigloher, C and Lachnit, T and Pita, L and Kupczok, A and Ribes, M and Stengel, ST and Rosenstiel, P and Dutilh, BE and Hentschel, U},
title = {A Phage Protein Aids Bacterial Symbionts in Eukaryote Immune Evasion.},
journal = {Cell host &amp; microbe},
volume = {},
number = {},
pages = {},
doi = {10.1016/j.chom.2019.08.019},
pmid = {31561965},
issn = {1934-6069},
abstract = {Phages are increasingly recognized as important members of host-associated microbiomes, with a vast genomic diversity. The new frontier is to understand how phages may affect higher order processes, such as in the context of host-microbe interactions. Here, we use marine sponges as a model to investigate the interplay between phages, bacterial symbionts, and eukaryotic hosts. Using viral metagenomics, we find that sponges, although massively filtering seawater, harbor species-specific and even individually unique viral signatures that are taxonomically distinct from other environments. We further discover a symbiont phage-encoded ankyrin-domain-containing protein, which is widely spread in phages of many host-associated contexts including human. We confirm in macrophage infection assays that the ankyrin protein (ANKp) modulates the eukaryotic host immune response against bacteria. We predict that the role of ANKp in nature is to facilitate coexistence in the tripartite interplay between phages, symbionts, and sponges and possibly many other host-microbe associations.},
}
@article {pmid31561208,
year = {2019},
author = {Brisbois, BW and Spiegel, JM and Harris, L},
title = {Health, environment and colonial legacies: Situating the science of pesticides, bananas and bodies in Ecuador.},
journal = {Social science &amp; medicine (1982)},
volume = {239},
number = {},
pages = {112529},
doi = {10.1016/j.socscimed.2019.112529},
pmid = {31561208},
issn = {1873-5347},
abstract = {Pesticide-related health impacts in Ecuador's banana industry illustrate the need to understand science's social production in the context of major North-South inequities. This paper explores colonialism's ongoing context-specific relationships to science, and what these imply for population health inquiry and praxis. Themes in postcolonial science and technology studies and critical Latin American scholarship guide this exploration, oriented around an ethnographic case study of bananas, pesticides and health in Ecuador. The challenge of explaining these impacts prompts us to explore discursive and contextual dynamics of pesticide toxicology and phytopathology, two disciplines integral to understanding pesticide-health linkages. The evolution of banana phytopathology reflects patterns of banana production and plant science in settings made accessible to scientists by European colonialism and American military interventions. Similarly, American foreign policy in Cold War-era Latin America created conditions for widespread pesticide exposures and accompanying health science research. Neocolonial representations of the global South interacted with these material realities in fostering generation of scientific knowledge. Implications for health praxis include troubling celebratory portrayals of global interconnectedness in the field of global health, motivating critical political economy and radical community-based approaches in their place. Another implication is a challenge to conciliatory corporate engagement approaches in health research, given banana production's symbiosis of scientifically 'productive' military and corporate initiatives. Similarly, the origins and evolution of toxicology should promote humility and precautionary approaches in addressing environmental injustices such as pesticide toxicity, given the role of corporate actors in promoting systematic underestimation of risk to vulnerable populations. Perhaps most unsettlingly, the very structures and processes that drive health inequities in Ecuador's banana industry simultaneously shape production of knowledge about those inequities. Public health scholars should thus move beyond simply carrying out more, or better, studies, and pursue the structural changes needed to redress historical and ongoing injustices.},
}
@article {pmid31560813,
year = {2019},
author = {Mee, ED and Gaylor, MG and Jasso-Selles, DE and Mizumoto, N and Gile, GH},
title = {Molecular phylogenetic position of Hoplonympha natator (Trichonymphea, Parabasalia).},
journal = {The Journal of eukaryotic microbiology},
volume = {},
number = {},
pages = {},
doi = {10.1111/jeu.12765},
pmid = {31560813},
issn = {1550-7408},
abstract = {Hoplonympha natator is an obligate symbiont of Paraneotermes simplicicornis (Kalotermitidae), from southwestern North America. Another Hoplonympha species inhabits Hodotermopsis sjostedti (Archotermopsidae), from montane Southeast Asia. The large phylogenetic and geographical distance between the hosts makes the distribution of Hoplonympha puzzling. Here we report the phylogenetic position of H. natator from P. simplicicornis through maximum likelihood and Bayesian analysis of 18S rRNA genes. The two Hoplonympha species form a clade with a deep node, making a recent symbiont transfer unlikely. The distribution of Hoplonympha may be due to an ancient transfer or strict vertical inheritance with differential loss from other hosts.},
}
@article {pmid31560603,
year = {2019},
author = {Aoki, T and Smith, JA and Kasson, MT and Freeman, S and Geiser, DM and Geering, ADW and O'Donnell, K},
title = {Three novel Ambrosia Fusarium Clade species producing clavate macroconidia known (F. floridanum and F. obliquiseptatum) or predicted (F. tuaranense) to be farmed by Euwallacea spp. (Coleoptera: Scolytinae) on woody hosts.},
journal = {Mycologia},
volume = {},
number = {},
pages = {1-17},
doi = {10.1080/00275514.2019.1647074},
pmid = {31560603},
issn = {1557-2536},
abstract = {The Ambrosia Fusarium Clade (AFC) comprises at least 16 genealogically exclusive species-level lineages within clade 3 of the Fusarium solani species complex (FSSC). These fungi are either known or predicted to be farmed by Asian Euwallacea ambrosia beetles (Coleoptera: Curculionidae: Scolytinae) in the tribe Xyleborini as a source of nutrition. To date, only 4 of the 16 AFC lineages have been described formally. In the absence of Latin binomials, an ad hoc nomenclature was developed to distinguish the 16 species lineages as AF-1 to AF-16. Herein, Fusarium species AF-3, AF-5, and AF-7 were formally described as F. floridanum, F. tuaranense, and F. obliquiseptatum, respectively. Fusarium floridanum farmed by E. interjectus on box elder (Acer negundo) in Gainesville, Florida, was distinguished morphologically by the production of sporodochial conidia that were highly variable in size and shape together with greenish-pigmented chlamydospores. Fusarium tuaranense was isolated from a beetle-damaged Paŕa rubber tree (Hevea brasiliense) in North Borneo, Malaysia, and was diagnosed by production of the smallest sporodochial conidia of any species within the AFC. Lastly, F. obliquiseptatum was farmed by an unnamed ambrosia beetle designated Euwallacea sp. 3 (E. fornicatus species complex) on avocado (Persea americana) in Queensland, Australia. It uniquely produces some clavate sporodochial conidia with oblique septa. Maximum likelihood analysis of a multilocus data set resolved these three novel AFC taxa as phylogenetically distinct species based on genealogical concordance. Particularly where introduced into exotic environments, these exotic mutualists pose a serious threat to the avocado industry, native forests, and urban landscapes in diverse regions throughout the world.},
}
@article {pmid31560378,
year = {2019},
author = {, and Fitzmaurice, C and Abate, D and Abbasi, N and Abbastabar, H and Abd-Allah, F and Abdel-Rahman, O and Abdelalim, A and Abdoli, A and Abdollahpour, I and Abdulle, ASM and Abebe, ND and Abraha, HN and Abu-Raddad, LJ and Abualhasan, A and Adedeji, IA and Advani, SM and Afarideh, M and Afshari, M and Aghaali, M and Agius, D and Agrawal, S and Ahmadi, A and Ahmadian, E and Ahmadpour, E and Ahmed, MB and Akbari, ME and Akinyemiju, T and Al-Aly, Z and AlAbdulKader, AM and Alahdab, F and Alam, T and Alamene, GM and Alemnew, BTT and Alene, KA and Alinia, C and Alipour, V and Aljunid, SM and Bakeshei, FA and Almadi, MAH and Almasi-Hashiani, A and Alsharif, U and Alsowaidi, S and Alvis-Guzman, N and Amini, E and Amini, S and Amoako, YA and Anbari, Z and Anber, NH and Andrei, CL and Anjomshoa, M and Ansari, F and Ansariadi, A and Appiah, SCY and Arab-Zozani, M and Arabloo, J and Arefi, Z and Aremu, O and Areri, HA and Artaman, A and Asayesh, H and Asfaw, ET and Ashagre, AF and Assadi, R and Ataeinia, B and Atalay, HT and Ataro, Z and Atique, S and Ausloos, M and Avila-Burgos, L and Avokpaho, EFGA and Awasthi, A and Awoke, N and Ayala Quintanilla, BP and Ayanore, MA and Ayele, HT and Babaee, E and Bacha, U and Badawi, A and Bagherzadeh, M and Bagli, E and Balakrishnan, S and Balouchi, A and Bärnighausen, TW and Battista, RJ and Behzadifar, M and Behzadifar, M and Bekele, BB and Belay, YB and Belayneh, YM and Berfield, KKS and Berhane, A and Bernabe, E and Beuran, M and Bhakta, N and Bhattacharyya, K and Biadgo, B and Bijani, A and Bin Sayeed, MS and Birungi, C and Bisignano, C and Bitew, H and Bjørge, T and Bleyer, A and Bogale, KA and Bojia, HA and Borzì, AM and Bosetti, C and Bou-Orm, IR and Brenner, H and Brewer, JD and Briko, AN and Briko, NI and Bustamante-Teixeira, MT and Butt, ZA and Carreras, G and Carrero, JJ and Carvalho, F and Castro, C and Castro, F and Catalá-López, F and Cerin, E and Chaiah, Y and Chanie, WF and Chattu, VK and Chaturvedi, P and Chauhan, NS and Chehrazi, M and Chiang, PP and Chichiabellu, TY and Chido-Amajuoyi, OG and Chimed-Ochir, O and Choi, JJ and Christopher, DJ and Chu, DT and Constantin, MM and Costa, VM and Crocetti, E and Crowe, CS and Curado, MP and Dahlawi, SMA and Damiani, G and Darwish, AH and Daryani, A and das Neves, J and Demeke, FM and Demis, AB and Demissie, BW and Demoz, GT and Denova-Gutiérrez, E and Derakhshani, A and Deribe, KS and Desai, R and Desalegn, BB and Desta, M and Dey, S and Dharmaratne, SD and Dhimal, M and Diaz, D and Dinberu, MTT and Djalalinia, S and Doku, DT and Drake, TM and Dubey, M and Dubljanin, E and Duken, EE and Ebrahimi, H and Effiong, A and Eftekhari, A and El Sayed, I and Zaki, MES and El-Jaafary, SI and El-Khatib, Z and Elemineh, DA and Elkout, H and Ellenbogen, RG and Elsharkawy, A and Emamian, MH and Endalew, DA and Endries, AY and Eshrati, B and Fadhil, I and Fallah, V and Faramarzi, M and Farhangi, MA and Farioli, A and Farzadfar, F and Fentahun, N and Fernandes, E and Feyissa, GT and Filip, I and Fischer, F and Fisher, JL and Force, LM and Foroutan, M and Freitas, M and Fukumoto, T and Futran, ND and Gallus, S and Gankpe, FG and Gayesa, RT and Gebrehiwot, TT and Gebremeskel, GG and Gedefaw, GA and Gelaw, BK and Geta, B and Getachew, S and Gezae, KE and Ghafourifard, M and Ghajar, A and Ghashghaee, A and Gholamian, A and Gill, PS and Ginindza, TTG and Girmay, A and Gizaw, M and Gomez, RS and Gopalani, SV and Gorini, G and Goulart, BNG and Grada, A and Ribeiro Guerra, M and Guimaraes, ALS and Gupta, PC and Gupta, R and Hadkhale, K and Haj-Mirzaian, A and Haj-Mirzaian, A and Hamadeh, RR and Hamidi, S and Hanfore, LK and Haro, JM and Hasankhani, M and Hasanzadeh, A and Hassen, HY and Hay, RJ and Hay, SI and Henok, A and Henry, NJ and Herteliu, C and Hidru, HD and Hoang, CL and Hole, MK and Hoogar, P and Horita, N and Hosgood, HD and Hosseini, M and Hosseinzadeh, M and Hostiuc, M and Hostiuc, S and Househ, M and Hussen, MM and Ileanu, B and Ilic, MD and Innos, K and Irvani, SSN and Iseh, KR and Islam, SMS and Islami, F and Jafari Balalami, N and Jafarinia, M and Jahangiry, L and Jahani, MA and Jahanmehr, N and Jakovljevic, M and James, SL and Javanbakht, M and Jayaraman, S and Jee, SH and Jenabi, E and Jha, RP and Jonas, JB and Jonnagaddala, J and Joo, T and Jungari, SB and Jürisson, M and Kabir, A and Kamangar, F and Karch, A and Karimi, N and Karimian, A and Kasaeian, A and Kasahun, GG and Kassa, B and Kassa, TD and Kassaw, MW and Kaul, A and Keiyoro, PN and Kelbore, AG and Kerbo, AA and Khader, YS and Khalilarjmandi, M and Khan, EA and Khan, G and Khang, YH and Khatab, K and Khater, A and Khayamzadeh, M and Khazaee-Pool, M and Khazaei, S and Khoja, AT and Khosravi, MH and Khubchandani, J and Kianipour, N and Kim, D and Kim, YJ and Kisa, A and Kisa, S and Kissimova-Skarbek, K and Komaki, H and Koyanagi, A and Krohn, KJ and Bicer, BK and Kugbey, N and Kumar, V and Kuupiel, D and La Vecchia, C and Lad, DP and Lake, EA and Lakew, AM and Lal, DK and Lami, FH and Lan, Q and Lasrado, S and Lauriola, P and Lazarus, JV and Leigh, J and Leshargie, CT and Liao, Y and Limenih, MA and Listl, S and Lopez, AD and Lopukhov, PD and Lunevicius, R and Madadin, M and Magdeldin, S and El Razek, HMA and Majeed, A and Maleki, A and Malekzadeh, R and Manafi, A and Manafi, N and Manamo, WA and Mansourian, M and Mansournia, MA and Mantovani, LG and Maroufizadeh, S and Martini, SMS and Mashamba-Thompson, TP and Massenburg, BB and Maswabi, MT and Mathur, MR and McAlinden, C and McKee, M and Meheretu, HAA and Mehrotra, R and Mehta, V and Meier, T and Melaku, YA and Meles, GG and Meles, HG and Melese, A and Melku, M and Memiah, PTN and Mendoza, W and Menezes, RG and Merat, S and Meretoja, TJ and Mestrovic, T and Miazgowski, B and Miazgowski, T and Mihretie, KMM and Miller, TR and Mills, EJ and Mir, SM and Mirzaei, H and Mirzaei, HR and Mishra, R and Moazen, B and Mohammad, DK and Mohammad, KA and Mohammad, Y and Darwesh, AM and Mohammadbeigi, A and Mohammadi, H and Mohammadi, M and Mohammadian, M and Mohammadian-Hafshejani, A and Mohammadoo-Khorasani, M and Mohammadpourhodki, R and Mohammed, AS and Mohammed, JA and Mohammed, S and Mohebi, F and Mokdad, AH and Monasta, L and Moodley, Y and Moosazadeh, M and Moossavi, M and Moradi, G and Moradi-Joo, M and Moradi-Lakeh, M and Moradpour, F and Morawska, L and Morgado-da-Costa, J and Morisaki, N and Morrison, SD and Mosapour, A and Mousavi, SM and Muche, AA and Muhammed, OSS and Musa, J and Nabhan, AR and Naderi, M and Nagarajan, AJ and Nagel, G and Nahvijou, A and Naik, G and Najafi, F and Naldi, L and Nam, HS and Nasiri, N and Nazari, J and Negoi, I and Neupane, S and Newcomb, PA and Nggada, HA and Ngunjiri, JW and Nguyen, CT and Nikniaz, L and Ningrum, DNA and Nirayo, YL and Nixon, MR and Nnaji, CA and Nojomi, M and Nosratnejad, S and Shiadeh, MN and Obsa, MS and Ofori-Asenso, R and Ogbo, FA and Oh, IH and Olagunju, AT and Olagunju, TO and Oluwasanu, MM and Omonisi, AE and Onwujekwe, OE and Oommen, AM and Oren, E and Ortega-Altamirano, DDV and Ota, E and Otstavnov, SS and Owolabi, MO and P A, M and Padubidri, JR and Pakhale, S and Pakpour, AH and Pana, A and Park, EK and Parsian, H and Pashaei, T and Patel, S and Patil, ST and Pennini, A and Pereira, DM and Piccinelli, C and Pillay, JD and Pirestani, M and Pishgar, F and Postma, MJ and Pourjafar, H and Pourmalek, F and Pourshams, A and Prakash, S and Prasad, N and Qorbani, M and Rabiee, M and Rabiee, N and Radfar, A and Rafiei, A and Rahim, F and Rahimi, M and Rahman, MA and Rajati, F and Rana, SM and Raoofi, S and Rath, GK and Rawaf, DL and Rawaf, S and Reiner, RC and Renzaho, AMN and Rezaei, N and Rezapour, A and Ribeiro, AI and Ribeiro, D and Ronfani, L and Roro, EM and Roshandel, G and Rostami, A and Saad, RS and Sabbagh, P and Sabour, S and Saddik, B and Safiri, S and Sahebkar, A and Salahshoor, MR and Salehi, F and Salem, H and Salem, MR and Salimzadeh, H and Salomon, JA and Samy, AM and Sanabria, J and Santric Milicevic, MM and Sartorius, B and Sarveazad, A and Sathian, B and Satpathy, M and Savic, M and Sawhney, M and Sayyah, M and Schneider, IJC and Schöttker, B and Sekerija, M and Sepanlou, SG and Sepehrimanesh, M and Seyedmousavi, S and Shaahmadi, F and Shabaninejad, H and Shahbaz, M and Shaikh, MA and Shamshirian, A and Shamsizadeh, M and Sharafi, H and Sharafi, Z and Sharif, M and Sharifi, A and Sharifi, H and Sharma, R and Sheikh, A and Shirkoohi, R and Shukla, SR and Si, S and Siabani, S and Silva, DAS and Silveira, DGA and Singh, A and Singh, JA and Sisay, S and Sitas, F and Sobngwi, E and Soofi, M and Soriano, JB and Stathopoulou, V and Sufiyan, MB and Tabarés-Seisdedos, R and Tabuchi, T and Takahashi, K and Tamtaji, OR and Tarawneh, MR and Tassew, SG and Taymoori, P and Tehrani-Banihashemi, A and Temsah, MH and Temsah, O and Tesfay, BE and Tesfay, FH and Teshale, MY and Tessema, GA and Thapa, S and Tlaye, KG and Topor-Madry, R and Tovani-Palone, MR and Traini, E and Tran, BX and Tran, KB and Tsadik, AG and Ullah, I and Uthman, OA and Vacante, M and Vaezi, M and Varona Pérez, P and Veisani, Y and Vidale, S and Violante, FS and Vlassov, V and Vollset, SE and Vos, T and Vosoughi, K and Vu, GT and Vujcic, IS and Wabinga, H and Wachamo, TM and Wagnew, FS and Waheed, Y and Weldegebreal, F and Weldesamuel, GT and Wijeratne, T and Wondafrash, DZ and Wonde, TE and Wondmieneh, AB and Workie, HM and Yadav, R and Yadegar, A and Yadollahpour, A and Yaseri, M and Yazdi-Feyzabadi, V and Yeshaneh, A and Yimam, MA and Yimer, EM and Yisma, E and Yonemoto, N and Younis, MZ and Yousefi, B and Yousefifard, M and Yu, C and Zabeh, E and Zadnik, V and Moghadam, TZ and Zaidi, Z and Zamani, M and Zandian, H and Zangeneh, A and Zaki, L and Zendehdel, K and Zenebe, ZM and Zewale, TA and Ziapour, A and Zodpey, S and Murray, CJL},
title = {Global, Regional, and National Cancer Incidence, Mortality, Years of Life Lost, Years Lived With Disability, and Disability-Adjusted Life-Years for 29 Cancer Groups, 1990 to 2017: A Systematic Analysis for the Global Burden of Disease Study.},
journal = {JAMA oncology},
volume = {},
number = {},
pages = {},
doi = {10.1001/jamaoncol.2019.2996},
pmid = {31560378},
issn = {2374-2445},
abstract = {Importance: Cancer and other noncommunicable diseases (NCDs) are now widely recognized as a threat to global development. The latest United Nations high-level meeting on NCDs reaffirmed this observation and also highlighted the slow progress in meeting the 2011 Political Declaration on the Prevention and Control of Noncommunicable Diseases and the third Sustainable Development Goal. Lack of situational analyses, priority setting, and budgeting have been identified as major obstacles in achieving these goals. All of these have in common that they require information on the local cancer epidemiology. The Global Burden of Disease (GBD) study is uniquely poised to provide these crucial data.<br><br>Objective: To describe cancer burden for 29 cancer groups in 195 countries from 1990 through 2017 to provide data needed for cancer control planning.<br><br>Evidence Review: We used the GBD study estimation methods to describe cancer incidence, mortality, years lived with disability, years of life lost, and disability-adjusted life-years (DALYs). Results are presented at the national level as well as by Socio-demographic Index (SDI), a composite indicator of income, educational attainment, and total fertility rate. We also analyzed the influence of the epidemiological vs the demographic transition on cancer incidence.<br><br>Findings: In 2017, there were 24.5 million incident cancer cases worldwide (16.8 million without nonmelanoma skin cancer [NMSC]) and 9.6 million cancer deaths. The majority of cancer DALYs came from years of life lost (97%), and only 3% came from years lived with disability. The odds of developing cancer were the lowest in the low SDI quintile (1 in 7) and the highest in the high SDI quintile (1 in 2) for both sexes. In 2017, the most common incident cancers in men were NMSC (4.3 million incident cases); tracheal, bronchus, and lung (TBL) cancer (1.5 million incident cases); and prostate cancer (1.3 million incident cases). The most common causes of cancer deaths and DALYs for men were TBL cancer (1.3 million deaths and 28.4 million DALYs), liver cancer (572 000 deaths and 15.2 million DALYs), and stomach cancer (542 000 deaths and 12.2 million DALYs). For women in 2017, the most common incident cancers were NMSC (3.3 million incident cases), breast cancer (1.9 million incident cases), and colorectal cancer (819 000 incident cases). The leading causes of cancer deaths and DALYs for women were breast cancer (601 000 deaths and 17.4 million DALYs), TBL cancer (596 000 deaths and 12.6 million DALYs), and colorectal cancer (414 000 deaths and 8.3 million DALYs).<br><br>Conclusions and Relevance: The national epidemiological profiles of cancer burden in the GBD study show large heterogeneities, which are a reflection of different exposures to risk factors, economic settings, lifestyles, and access to care and screening. The GBD study can be used by policy makers and other stakeholders to develop and improve national and local cancer control in order to achieve the global targets and improve equity in cancer care.},
}
@article {pmid31559908,
year = {2019},
author = {Kale, VP},
title = {Application of &quot;primed&quot; Mesenchymal Stromal Cells in hematopoietic stem cell transplantation: Current status and Future prospects.},
journal = {Stem cells and development},
volume = {},
number = {},
pages = {},
doi = {10.1089/scd.2019.0149},
pmid = {31559908},
issn = {1557-8534},
abstract = {Regenerative potential of Mesenchymal Stem/Stromal cells (MSCs) has led to their application in various cellular therapies. Since in vivo these cells are present in very low numbers, they need expansion in culture to get clinically relevant numbers; however, such long-term ex vivo manipulation leads to loss of their regenerative capacity. Although use of naïve MSCs is still the most common approach used in various therapies, several strategies, both genetic and pharmacological, are being tried out to boost the regenerative capacity of in vitro expanded MSCs. Such manipulations are very commonly reported for regeneration of various tissues like bone, cartilage, kidney, pancreas, etc. Likewise, several efforts have been made to investigate priming of MSCs to enhance their immuno-regulatory activity, but such efforts have not been made to the same extent for enhancing the efficacy of hematopoietic stem cell transplantation (HSCT). Development of such approaches for HSCT would not only be useful for enhancing the transplantation efficacy of cord blood cells, which are fewer in numbers, and aged HSCs, which could be functionally compromised, but also for genetically modified HSCs, which are likely to be both, fewer in number and also functionally compromised. This review specifically deals with application of &quot;primed&quot; MSCs in the scenario of HSCT.},
}
@article {pmid31558429,
year = {2019},
author = {Chahar, DS and Ravindran, S and Pisal, SS},
title = {Monoclonal antibody purification and its progression to commercial scale.},
journal = {Biologicals : journal of the International Association of Biological Standardization},
volume = {},
number = {},
pages = {},
doi = {10.1016/j.biologicals.2019.09.007},
pmid = {31558429},
issn = {1095-8320},
abstract = {With the advancements in upstream technologies, the capacity for monoclonal antibody (mAb) production has transformed from a few milligrams to grams per liter. These titers lead to enormous pressure on downstream processes (DSPs), which need to be reworked to achieve higher efficiency and better utilization of available resources. Various parameters, such as column sizing, aggregate removal, filtration and volume handling, must be considered while designing a facility for commercial scale. If any of these critical parameters are not defined during the facility design stage, collapse of the process can result, further resulting in commercial loss and delaying entry of the product into the market. Therefore, during the facility design stage, the process requirements, space utilization, process efficiency and advanced manufacturing systems must be evaluated appropriately before implementation on a commercial scale.},
}
@article {pmid31557944,
year = {2019},
author = {Brígido, C and Menéndez, E and Paço, A and Glick, BR and Belo, A and Félix, MR and Oliveira, S and Carvalho, M},
title = {Mediterranean Native Leguminous Plants: A Reservoir of Endophytic Bacteria with Potential to Enhance Chickpea Growth under Stress Conditions.},
journal = {Microorganisms},
volume = {7},
number = {10},
pages = {},
doi = {10.3390/microorganisms7100392},
pmid = {31557944},
issn = {2076-2607},
support = {UID/AGR/00115/2013//Fundação para a Ciência e a Tecnologia/ ; POCI-01-0145-FEDER-016810 (PTDC/AGR-PRO/2978/2014)//Fundação para a Ciência e a Tecnologia-FEDER-COMPETE2020/ ; ALT20-03-0145-FEDER-000039//Portugal 2020/Alentejo 2020/ ; },
abstract = {Bacterial endophytes, a subset of a plant's microbiota, can facilitate plant growth by a number of different mechanisms. The aims of this study were to assess the diversity and functionality of endophytic bacterial strains from internal root tissues of native legume species grown in two distinct sites in South of Portugal and to evaluate their ability to promote plant growth. Here, 122 endophytic bacterial isolates were obtained from 12 different native legume species. Most of these bacteria possess at least one of the plant growth-promoting features tested in vitro, with indole acetic acid production being the most common feature among the isolates followed by the production of siderophores and inorganic phosphate solubilization. The results of in planta experiments revealed that co-inoculation of chickpea plants with specific endophytic bacteria along with N2-fixing symbionts significantly improved the total biomass of chickpea plants, in particular when these plants were grown under saline conditions. Altogether, this study revealed that Mediterranean native legume species are a reservoir of plant growth-promoting bacteria, that are also tolerant to salinity and to toxic levels of Mn. Thus, these bacterial endophytes are well adapted to common constraints present in soils of this region which constitutes important factors to consider in the development of bacterial inoculants for stressful conditions in the Mediterranean region.},
}
@article {pmid30650116,
year = {2019},
author = {Akami, M and Andongma, AA and Zhengzhong, C and Nan, J and Khaeso, K and Jurkevitch, E and Niu, CY and Yuval, B},
title = {Intestinal bacteria modulate the foraging behavior of the oriental fruit fly Bactrocera dorsalis (Diptera: Tephritidae).},
journal = {PloS one},
volume = {14},
number = {1},
pages = {e0210109},
doi = {10.1371/journal.pone.0210109},
pmid = {30650116},
issn = {1932-6203},
mesh = {Animals ; Behavior, Animal/*physiology ; Feeding Behavior/*physiology ; Female ; Gastrointestinal Microbiome/*physiology ; Larva/physiology ; Male ; Pupa/physiology ; Symbiosis/physiology ; Tephritidae/microbiology/*physiology ; },
abstract = {The gut microbiome of insects directly or indirectly affects the metabolism, immune status, sensory perception and feeding behavior of its host. Here, we examine the hypothesis that in the oriental fruit fly (Bactrocera dorsalis, Diptera: Tephritidae), the presence or absence of gut symbionts affects foraging behavior and nutrient ingestion. We offered protein-starved flies, symbiotic or aposymbiotic, a choice between diets containing all amino acids or only the non-essential ones. The different diets were presented in a foraging arena as drops that varied in their size and density, creating an imbalanced foraging environment. Suppressing the microbiome resulted in significant changes of the foraging behavior of both male and female flies. Aposymbiotic flies responded faster to the diets offered in experimental arenas, spent more time feeding, ingested more drops of food, and were constrained to feed on time-consuming patches (containing small drops of food), when these offered the full complement of amino acids. We discuss these results in the context of previous studies on the effect of the gut microbiome on host behavior, and suggest that these be extended to the life history dimension.},
}
@article {pmid29625978,
year = {2018},
author = {McGlynn, SE and Chadwick, GL and O'Neill, A and Mackey, M and Thor, A and Deerinck, TJ and Ellisman, MH and Orphan, VJ},
title = {Subgroup Characteristics of Marine Methane-Oxidizing ANME-2 Archaea and Their Syntrophic Partners as Revealed by Integrated Multimodal Analytical Microscopy.},
journal = {Applied and environmental microbiology},
volume = {84},
number = {11},
pages = {},
pmid = {29625978},
issn = {1098-5336},
support = {P41 GM103412/GM/NIGMS NIH HHS/United States ; },
mesh = {Anaerobiosis ; Archaea/*classification/metabolism/*ultrastructure ; Deltaproteobacteria/metabolism/ultrastructure ; Geologic Sediments/microbiology ; In Situ Hybridization, Fluorescence ; Methane/*metabolism ; Microbial Consortia ; Microscopy, Electron ; Oxidation-Reduction ; Phylogeny ; *Symbiosis ; },
abstract = {Phylogenetically diverse environmental ANME archaea and sulfate-reducing bacteria cooperatively catalyze the anaerobic oxidation of methane oxidation (AOM) in multicelled consortia within methane seep environments. To better understand these cells and their symbiotic associations, we applied a suite of electron microscopy approaches, including correlative fluorescence in situ hybridization-electron microscopy (FISH-EM), transmission electron microscopy (TEM), and serial block face scanning electron microscopy (SBEM) three-dimensional (3D) reconstructions. FISH-EM of methane seep-derived consortia revealed phylogenetic variability in terms of cell morphology, ultrastructure, and storage granules. Representatives of the ANME-2b clade, but not other ANME-2 groups, contained polyphosphate-like granules, while some bacteria associated with ANME-2a/2c contained two distinct phases of iron mineral chains resembling magnetosomes. 3D segmentation of two ANME-2 consortium types revealed cellular volumes of ANME and their symbiotic partners that were larger than previous estimates based on light microscopy. Polyphosphate-like granule-containing ANME (tentatively termed ANME-2b) were larger than both ANME with no granules and partner bacteria. This cell type was observed with up to 4 granules per cell, and the volume of the cell was larger in proportion to the number of granules inside it, but the percentage of the cell occupied by these granules did not vary with granule number. These results illuminate distinctions between ANME-2 archaeal lineages and partnering bacterial populations that are apparently unified in their ability to perform anaerobic methane oxidation.IMPORTANCE Methane oxidation in anaerobic environments can be accomplished by a number of archaeal groups, some of which live in syntrophic relationships with bacteria in structured consortia. Little is known of the distinguishing characteristics of these groups. Here, we applied imaging approaches to better understand the properties of these cells. We found unexpected morphological, structural, and volume variability of these uncultured groups by correlating fluorescence labeling of cells with electron microscopy observables.},
}
@article {pmid29205373,
year = {2018},
author = {Huang, F and Lankau, R and Peng, S},
title = {Coexistence via coevolution driven by reduced allelochemical effects and increased tolerance to competition between invasive and native plants.},
journal = {The New phytologist},
volume = {218},
number = {1},
pages = {357-369},
doi = {10.1111/nph.14937},
pmid = {29205373},
issn = {1469-8137},
mesh = {*Adaptation, Physiological ; *Biological Evolution ; Brassicaceae/physiology ; Glucosinolates/analysis ; *Introduced Species ; Linear Models ; Pheromones/*metabolism ; *Symbiosis ; Urticaceae/physiology ; },
abstract = {Coevolution can promote long-term coexistence of two competing species if selection acts to reduce the fitness inequality between competitors and/or strengthen negative frequency dependence within each population. However, clear coevolution between plant competitors has been rarely documented. Plant invasions offer opportunities to capture the process of coevolution. Here we investigated how the developing relationship between an invasive forb, Alliaria petiolata, and a native competitor, Pilea pumila, may affect their long-term coexistence, by testing the competitive effects of populations of varying lengths of co-occurrence on each other across a chronosequence of invasion history. Alliaria petiolata and P. pumila tended to develop greater tolerance to competition over invasion history. Their coexistence was promoted more by increases in stabilizing relative to equalizing processes. These changes likely stem in part from reductions in allelopathic traits in the invader and evolution of tolerance in the native. These results suggested that some native species can evolve tolerance against the competitive effects of strong invaders, which likely promoted their persistence in invaded communities. However, the potential for coevolutionary rescue of competing populations is likely to vary across native species, and evolutionary processes should not be expected to compensate for the ecological consequences of exotic invasions.},
}
@article {pmid27604856,
year = {2018},
author = {Pichersky, E and Raguso, RA},
title = {Why do plants produce so many terpenoid compounds?.},
journal = {The New phytologist},
volume = {220},
number = {3},
pages = {692-702},
doi = {10.1111/nph.14178},
pmid = {27604856},
issn = {1469-8137},
support = {IOS-1025636//National Science Foundation of the USA/International ; DEB-1342792//National Science Foundation of the USA/International ; },
mesh = {Animals ; Humans ; Phylogeny ; Plants/*metabolism ; Symbiosis ; Terpenes/chemistry/*metabolism ; },
abstract = {All plants synthesize a suite of several hundred terpenoid compounds with roles that include phytohormones, protein modification reagents, anti-oxidants, and more. Different plant lineages also synthesize hundreds of distinct terpenoids, with the total number of such specialized plant terpenoids estimated in the scores of thousands. Phylogenetically restricted terpenoids are implicated in defense or in the attraction of beneficial organisms. A popular hypothesis is that the ability of plants to synthesize new compounds arose incrementally by selection when, as a result of gradual changes in their biotic partners and enemies, the 'old' plant compounds were no longer effective, a process dubbed the 'coevolutionary arms race'. Another hypothesis posits that often the sheer diversity of such compounds provides benefits that a single compound cannot. In this article, we review the unique features of the biosynthetic apparatus of terpenes in plants that facilitate the production of large numbers of distinct terpenoids in each species and how facile genetic and biochemical changes can lead to the further diversification of terpenoids. We then discuss evidence relating to the hypotheses that given ecological functions may be enhanced by the presence of mixtures of terpenes and that the acquisition of new functions by terpenoids may favor their retention once the original functions are lost.},
}
@article {pmid31555282,
year = {2019},
author = {Goto, Y},
title = {Epithelial Cells as a Transmitter of Signals From Commensal Bacteria and Host Immune Cells.},
journal = {Frontiers in immunology},
volume = {10},
number = {},
pages = {2057},
doi = {10.3389/fimmu.2019.02057},
pmid = {31555282},
issn = {1664-3224},
abstract = {Intestinal epithelial cells (IECs) are non-hematopoietic cells that form a physical barrier against external antigens. Recent studies indicate that IECs have pleiotropic functions in the regulation of luminal microbiota and the host immune system. IECs produce various immune modulatory cytokines and chemokines in response to commensal bacteria and contribute to developing the intestinal immune system. In contrast, IECs receive cytokine signals from immune cells and produce various immunological factors against luminal bacteria. This bidirectional function of IECs is critical to regulate homeostasis of microbiota and the host immune system. Disruption of the epithelial barrier leads to detrimental host diseases such as inflammatory bowel disease, colonic cancer, and pathogenic infection. This review provides an overview of the functions and physiology of IECs and highlights their bidirectional functions against luminal bacteria and immune cells, which contribute to maintaining gut homeostasis.},
}
@article {pmid31553827,
year = {2019},
author = {Tong, CG and Wu, FH and Yuan, YH and Chen, YR and Lin, CS},
title = {High-efficiency CRISPR/Cas-based editing of Phalaenopsis orchid MADS genes.},
journal = {Plant biotechnology journal},
volume = {},
number = {},
pages = {},
doi = {10.1111/pbi.13264},
pmid = {31553827},
issn = {1467-7652},
abstract = {Phalaenopsis orchids are popular potted ornamental plants around the world due to their beauty, floral diversity, and long indoor blooming period. Orchids are also important in plant research, having tiny, dust-like seeds, crassulacean acid metabolism photosynthesis, complex deletion of the genes encoding NADH dehydrogenase subunits, and mycorrhizal symbiosis.},
}
@article {pmid31552366,
year = {2019},
author = {Silva-Junior, EA and Paludo, CR and Amaral, JG and Gallon, ME and Gobbo-Neto, L and Nascimento, FS and Lopes, NP},
title = {Chemical Diversity in a Stingless Bee-Plant Symbiosis.},
journal = {ACS omega},
volume = {4},
number = {12},
pages = {15208-15214},
doi = {10.1021/acsomega.9b02096},
pmid = {31552366},
issn = {2470-1343},
abstract = {Bees are essential pollinators on earth, supporting forest equilibrium and human agriculture. The chemistry of the stingless bee-plant symbiosis is a complex and not completely understood phenomenon. Here, we combined untargeted tandem mass spectrometry, molecular networking, and multivariate statistical analysis to investigate the chemical diversity in colonies of the stingless bee Scaptotrigona depilis. Flavonoids were the most representative and diverse group of plant metabolites detected, indicating the importance of these biologically active natural products to the bees. We unveiled the metabolome, mapped the distribution of plant metabolites in stingless bee colonies, and digitized the chemical data into a public database.},
}
@article {pmid31552222,
year = {2019},
author = {Thuan, NH and An, TT and Shrestha, A and Canh, NX and Sohng, JK and Dhakal, D},
title = {Recent Advances in Exploration and Biotechnological Production of Bioactive Compounds in Three Cyanobacterial Genera: Nostoc, Lyngbya, and Microcystis.},
journal = {Frontiers in chemistry},
volume = {7},
number = {},
pages = {604},
doi = {10.3389/fchem.2019.00604},
pmid = {31552222},
issn = {2296-2646},
abstract = {Cyanobacteria, are only Gram-negative bacteria with the capacity of oxygenic photosynthesis, so termed as &quot;Cyanophyta&quot; or &quot;blue-green algae.&quot; Their habitat is ubiquitous, which includes the diverse environments, such as soil, water, rock and other organisms (symbiosis, commensalism, or parasitism, etc.,). They are characterized as prominent producers of numerous types of important compounds with anti-microbial, anti-viral, anti-inflammatory and anti-tumor properties. Among the various cyanobacterial genera, members belonging to genera Nostoc, Lyngbya, and Microcystis possess greater attention. The major reason for that is the strains belonging to these genera produce the compounds with diverse activities/structures, including compounds in preclinical and/or clinical trials (cryptophycin and curacin), or the compounds retaining unique activities such as protease inhibitor (micropeptins and aeruginosins). Most of these compounds were tested for their efficacy and mechanism of action(MOA) through in vitro and/or in vivo studies. Recently, the advances in culture techniques of these cyanobacteria, and isolation, purification, and chromatographic analysis of their compounds have revealed insurmountable novel bioactive compounds from these cyanobacteria. This review provides comprehensive update on the origin, isolation and purification methods, chemical structures and biological activities of the major compounds from Nostoc, Lyngbya, and Microcystis. In addition, multi-omics approaches and biotechnological production of compounds from selected cyanobacterial genera have been discussed.},
}
@article {pmid31551977,
year = {2019},
author = {Bouznif, B and Guefrachi, I and Rodríguez de la Vega, RC and Hungria, M and Mars, M and Alunni, B and Shykoff, JA},
title = {Phylogeography of the Bradyrhizobium spp. Associated With Peanut, Arachis hypogaea: Fellow Travelers or New Associations?.},
journal = {Frontiers in microbiology},
volume = {10},
number = {},
pages = {2041},
doi = {10.3389/fmicb.2019.02041},
pmid = {31551977},
issn = {1664-302X},
abstract = {Legume plants have colonized almost all terrestrial biotopes. Their ecological success is partly due to the selective advantage provided by their symbiotic association with nitrogen-fixing bacteria called rhizobia, which allow legumes to thrive on marginal lands and nitrogen depleted soils where non-symbiotic plants cannot grow. Additionally, their symbiotic capacities result in a high protein content in their aerial parts and seeds. This interesting nutritional value has led to the domestication and agricultural exploitation of several legumes grown for seeds and/or fodder for human and domestic animal consumption. Several cultivated legume species are thus grown far beyond their natural geographic range. Other legume species have become invasives, spreading into new habitats. The cultivation and establishment of legume species outside of their original range requires either that they are introduced or cultivated along with their original symbiotic partner or that they find an efficient symbiotic partner in their introduced habitat. The peanut, Arachis hypogaea, a native of South America, is now cultivated throughout the world. This species forms root nodules with Bradyrhizobium, but it is unclear whether these came with the seeds from their native range or were acquired locally. Here we propose to investigate the phylogeography of Bradyrhizobium spp. associated with a number of different wild and cultivated legume species from a range of geographical areas, including numerous strains isolated from peanut roots across the areas of peanut cultivation. This will allow us to address the question of whether introduced/cultivated peanuts associate with bacteria from their original geographic range, i.e., were introduced together with their original bacterial symbionts, or whether they acquired their current associations de novo from the bacterial community within the area of introduction. We will base the phylogenetic analysis on sequence data from both housekeeping and core genes and a symbiotic gene (nif). Differences between the phylogenetic signal of symbiotic and non-symbiotic genes could result from horizontal transfer of symbiosis capacity. Thus this study will also allow us to elucidate the processes by which this symbiotic association has evolved within this group of Bradyrhizobium spp.},
}
@article {pmid31551973,
year = {2019},
author = {Scolari, F and Casiraghi, M and Bonizzoni, M},
title = {Aedes spp. and Their Microbiota: A Review.},
journal = {Frontiers in microbiology},
volume = {10},
number = {},
pages = {2036},
doi = {10.3389/fmicb.2019.02036},
pmid = {31551973},
issn = {1664-302X},
abstract = {Aedes spp. are a major public health concern due to their ability to be efficient vectors of dengue, Chikungunya, Zika, and other arboviruses. With limited vaccines available and no effective therapeutic treatments against arboviruses, the control of Aedes spp. populations is currently the only strategy to prevent disease transmission. Host-associated microbes (i.e., microbiota) recently emerged as a promising field to be explored for novel environmentally friendly vector control strategies. In particular, gut microbiota is revealing its impact on multiple aspects of Aedes spp. biology, including vector competence, thus being a promising target for manipulation. Here we describe the technological advances, which are currently expanding our understanding of microbiota composition, abundance, variability, and function in the two main arboviral vectors, the mosquitoes Aedes aegypti and Aedes albopictus. Aedes spp. microbiota is described in light of its tight connections with the environment, with which mosquitoes interact during their various developmental stages. Unraveling the dynamic interactions among the ecology of the habitat, the mosquito and the microbiota have the potential to uncover novel physiological interdependencies and provide a novel perspective for mosquito control.},
}
@article {pmid31549137,
year = {2019},
author = {Fernández-Marín, B and López-Pozo, M and Perera-Castro, AV and Irati Arzac, M and Saenz-Ceniceros, A and Colesie, C and de Los Ríos, A and Sancho, LG and Pintado, A and Laza, JM and Pérez-Ortega, S and García-Plazaola, JI},
title = {Symbiosis at its limits: ecophysiological consequences of lichenization to the genus Prasiola in Antarctica.},
journal = {Annals of botany},
volume = {},
number = {},
pages = {},
doi = {10.1093/aob/mcz149},
pmid = {31549137},
issn = {1095-8290},
abstract = {BACKGROUND AND AIMS: Lichens represent a symbiotic relationship between at least one fungal and one photosynthetic partner. The association between the lichen-forming fungus Mastodia tessellata (Verrucariaceae) and different species of Prasiola (Trebouxiophyceae) has an amphipolar distribution and represents a unique case study for the understanding of lichen symbiosis because of the macroalgal nature of the photobiont, the flexibility of the symbiotic interaction and the co-existence of free-living and lichenized forms in the same microenvironment. In this context, we aimed to (1) characterise the photosynthetic performance of co-occurring populations of free-living and lichenized Prasiola and (2) assess the effect of the symbiosis on the water relations in Prasiola, including its tolerance to desiccation and its survival and performance under sub-zero temperatures.<br><br>METHODS: Photochemical responses to irradiance, desiccation, and freezing temperature and pressure-volume curves of co-existing free-living and lichenized Prasiola thalli were measured in situ in Livingston Island (Maritime Antarctica). Analyses of photosynthetic pigment, glass transition and ice nucleation temperatures, surface hydrophobicity extent and molecular analyses were conducted in the lab.<br><br>KEY RESULTS: Free-living and lichenized forms of Prasiola were identified as two different species: P. crispa and Prasiola sp., respectively. While the lichenization appears to have no effect on the photochemical performance of the alga, or in its tolerance to desiccation (at short-term), the symbiotic lifestyle involves (1) changes in water relations, (2) a considerable decrease in the net carbon balance and (3) an enhanced freezing tolerance.<br><br>CONCLUSIONS: Our results support an improved tolerance to subzero temperature as main benefit of lichenization for the photobiont, but highlight that lichenization represents a delicate equilibrium between a mutualistic and a less reciprocal relationship. In a warmer climate scenario, the spread of the free-living Prasiola in detriment of the lichen form would be likely, with unknown consequences for the Maritime Antarctic ecosystems.},
}
@article {pmid31549018,
year = {2019},
author = {Wang, J and Hossain, MS and Lyu, Z and Schmutz, J and Stacey, G and Xu, D and Joshi, T},
title = {SoyCSN: Soybean context-specific network analysis and prediction based on tissue-specific transcriptome data.},
journal = {Plant direct},
volume = {3},
number = {9},
pages = {e00167},
doi = {10.1002/pld3.167},
pmid = {31549018},
issn = {2475-4455},
abstract = {The Soybean Gene Atlas project provides a comprehensive map for understanding gene expression patterns in major soybean tissues from flower, root, leaf, nodule, seed, and shoot and stem. The RNA-Seq data generated in the project serve as a valuable resource for discovering tissue-specific transcriptome behavior of soybean genes in different tissues. We developed a computational pipeline for Soybean context-specific network (SoyCSN) inference with a suite of prediction tools to analyze, annotate, retrieve, and visualize soybean context-specific networks at both transcriptome and interactome levels. BicMix and Cross-Conditions Cluster Detection algorithms were applied to detect modules based on co-expression relationships across all the tissues. Soybean context-specific interactomes were predicted by combining soybean tissue gene expression and protein-protein interaction data. Functional analyses of these predicted networks provide insights into soybean tissue specificities. For example, under symbiotic, nitrogen-fixing conditions, the constructed soybean leaf network highlights the connection between the photosynthesis function and rhizobium-legume symbiosis. SoyCSN data and all its results are publicly available via an interactive web service within the Soybean Knowledge Base (SoyKB) at http://soykb.org/SoyCSN. SoyCSN provides a useful web-based access for exploring context specificities systematically in gene regulatory mechanisms and gene relationships for soybean researchers and molecular breeders.},
}
@article {pmid31529895,
year = {2019},
author = {Ning, CH and Li, WB and Zhang, C and Liu, RJ},
title = {[Growth-promotion and disease control effects on chili and eggplant by arbuscular mycorrhizal fungi and plant symbiotic actinomycetes].},
journal = {Ying yong sheng tai xue bao = The journal of applied ecology},
volume = {30},
number = {9},
pages = {3195-3202},
doi = {10.13287/j.1001-9332.201909.037},
pmid = {31529895},
issn = {1001-9332},
mesh = {*Actinobacteria ; Actinomyces ; Capsicum/*microbiology ; Fungi ; *Mycorrhizae ; Plant Roots ; Solanum melongena/*microbiology ; Symbiosis ; },
abstract = {Arbuscular mycorrhizal fungi (AMF) or plant symbiotic actinomycetes (PSA) play an important role in stimulating plant growth, antagonizing pathogens, tolerating stress, and controlling plant disease. However, whether there is a synergistic effect between AMF and PSA in promoting plant growth and controlling disease is worth exploring. The aim of this study was to evaluate the effects of AMF and PSA on growth-promotion and controlling disease on Solanaceae vegetables and to obtain effective AMF+PSA combinations. Under greenhouse pot conditions, chili (Capsicum annu-um, cultivar: Yangjiaojiao) and eggplant (Solanum melongena, cultivar: Heiguanchangqie) were inoculated with or without AMF Funneliformis mosseae (Fm), Glomus versiforme (Gv), PSA Streptomyces globosus H6-1, Streptomyces rochei S2-2, Streptomyces coralus D11-4 or/and pathogenic fungi Botrytis cinerea. There were a total of 48 treatments. The growth, disease and root symbiont development of plants were determined. The results showed that Fm and PSA could promote each other's colonization, while Gv and PSA inhibited each other. Compared with the control, AMF, PSA and AMF+PSA improved the photosynthetic performance, root activity, and growth of chili and eggplant. Under the condition of inoculation with pathogenic fungi, AMF and/or PSA treatment significantly increased growth and reduced the disease index of plants, with the effects of PSA being greater than that of AMF. Fm+H6-1 combination had the best effect on the growth-promotion and controlling disease of chili plants, with the controlling effect on gray mold reaching 69.1%. Fm+ D11-4 had the best effect on the growth promotion and controlling disease of eggplant, the controlling effect of which on gray mold reached 75.5%. Fm+H6-1 andFm+D11-4 were efficient combinations of chili and eggplant for promoting growth and controlling disease under the conditions of this experiment. Further tests in field are needed.},
}
@article {pmid30408219,
year = {2018},
author = {Martin, FM and Harrison, MJ and Lennon, S and Lindahl, B and Öpik, M and Polle, A and Requena, N and Selosse, MA},
title = {Cross-scale integration of mycorrhizal function.},
journal = {The New phytologist},
volume = {220},
number = {4},
pages = {941-946},
doi = {10.1111/nph.15493},
pmid = {30408219},
issn = {1469-8137},
support = {ANR-11-LABX 0002 01//Laboratory of Excellence Advanced Research on the Biology of Tree and Forest Ecosystems/International ; IUT20-28//Estonian Research Council/International ; //European Regional Development Fund (Centre of Excellence EcolChange)/International ; //ERA-NET Cofund BiodivERsA3 (SoilMan)/International ; },
mesh = {Fungi/physiology ; Microbiota ; Mycorrhizae/*physiology ; Plants/microbiology ; Symbiosis ; },
}
@article {pmid30130506,
year = {2018},
author = {Simpson, C},
title = {Evolution: Serving Up Light.},
journal = {Current biology : CB},
volume = {28},
number = {16},
pages = {R873-R875},
doi = {10.1016/j.cub.2018.05.037},
pmid = {30130506},
issn = {1879-0445},
mesh = {Animals ; *Anthozoa ; *Dinoflagellida ; Symbiosis ; },
abstract = {Dinoflagellate algae form symbiotic partnerships with hosts from across a wide swath of the tree of life. New work shows that the genus Symbiodinium should now be considered a family, and importantly that the group is 110 million years older than previously thought. This expanded time period resolves long-standing questions about the evolution of photosymbiosis.},
}
@article {pmid30022580,
year = {2018},
author = {Samo, TJ and Kimbrel, JA and Nilson, DJ and Pett-Ridge, J and Weber, PK and Mayali, X},
title = {Attachment between heterotrophic bacteria and microalgae influences symbiotic microscale interactions.},
journal = {Environmental microbiology},
volume = {20},
number = {12},
pages = {4385-4400},
doi = {10.1111/1462-2920.14357},
pmid = {30022580},
issn = {1462-2920},
support = {SCW1039//Department of Energy's Genome Sciences Program/International ; AC52-07NA27344//Lawrence Livermore National Laboratory/International ; //Texas A&amp;M University/International ; },
mesh = {Bacteria/*metabolism ; Biofuels ; Carbon/metabolism ; Diatoms/metabolism/microbiology ; Heterotrophic Processes ; Microalgae/*metabolism/*microbiology ; Phylogeny ; *Symbiosis ; },
abstract = {The surface and surroundings of microalgal cells (phycosphere) are critical interaction zones but have been difficult to functionally interrogate due to methodological limitations. We examined effects of phycosphere-associated bacteria for two biofuel-relevant microalgal species (Phaeodactylum tricornutum and Nannochloropsis salina) using stable isotope tracing and high spatial resolution mass spectrometry imaging (NanoSIMS) to quantify elemental exchanges at the single-cell level. Each algal species responded differently to bacterial attachment. In P. tricornutum, a high percentage of cells had attached bacteria (92%-98%, up to eight bacteria per alga) and fixed 64% more carbon with attached bacteria compared to axenic cells. In contrast, N. salina cells were less commonly associated with bacteria (42%-63%), harboured fewer bacteria per alga, and fixed 10% more carbon without attached bacteria compared to axenic cells. An uncultivated bacterium related to Haliscomenobacter sp. was identified as an effective mutualist; it increased carbon fixation when attached to P. tricornutum and incorporated 71% more algal-fixed carbon relative to other bacteria. Our results illustrate how phylogenetic identity and physical location of bacteria and algae facilitate diverse metabolic responses. Phycosphere-mediated, mutualistic chemical exchanges between autotrophs and heterotrophs may be a fruitful means to increase microalgal productivity for applied engineering efforts.},
}
@article {pmid29581469,
year = {2018},
author = {Hunt, VL and Hino, A and Yoshida, A and Kikuchi, T},
title = {Comparative transcriptomics gives insights into the evolution of parasitism in Strongyloides nematodes at the genus, subclade and species level.},
journal = {Scientific reports},
volume = {8},
number = {1},
pages = {5192},
pmid = {29581469},
issn = {2045-2322},
mesh = {Animals ; Helminth Proteins/classification/genetics ; Humans ; Larva/genetics/pathogenicity ; Life Cycle Stages/genetics ; *Phylogeny ; Rats, Wistar ; Rodentia/parasitology ; Strongyloides/*genetics/pathogenicity ; Strongyloidiasis/*genetics/parasitology ; Symbiosis/genetics ; Transcriptome/*genetics ; },
abstract = {Strongyloides spp., gastrointestinal nematode parasites of humans and other animals, have genetically identical parasitic and free-living adult life cycle stages. This is an almost unique feature amongst nematodes and comparison of these two stages can provide insights into the genetic basis and evolution of Strongyloides nematode parasitism. Here, we present RNAseq data for S. venezuelensis, a parasite of rodents, and identify genes that are differentially expressed in parasitic and free-living life cycle stages. Comparison of these data with analogous RNAseq data for three other Strongyloides spp., has identified key protein-coding gene families with a putative role in parasitism including WAGO-like Argonautes (at the genus level) and speckle-type POZ-like coding genes (S. venezuelensis-S. papillosus phylogenetic subclade level). Diverse gene families are uniquely upregulated in the parasitic stage of all four Strongyloides species, including a distinct upregulation of genes encoding cytochrome P450 in S. venezuelensis, suggesting some diversification of the molecular tools used in the parasitic life cycle stage among individual species. Together, our results identify key gene families with a putative role in Strongyloides parasitism or features of the parasitic life cycle stage, and deepen our understanding of parasitism evolution among Strongyloides species.},
}
@article {pmid29499213,
year = {2018},
author = {Bi, J and Sehgal, A and Williams, JA and Wang, YF},
title = {Wolbachia affects sleep behavior in Drosophila melanogaster.},
journal = {Journal of insect physiology},
volume = {107},
number = {},
pages = {81-88},
doi = {10.1016/j.jinsphys.2018.02.011},
pmid = {29499213},
issn = {1879-1611},
mesh = {Animals ; Arousal ; Circadian Rhythm ; Drosophila melanogaster/*microbiology/*physiology ; Female ; Insect Proteins ; Male ; *Sleep ; Symbiosis ; Up-Regulation ; Wolbachia/*physiology ; },
abstract = {Wolbachia are endosymbiotic bacteria present in a wide range of insects. Although their dramatic effects on host reproductive biology have been well studied, the effects of Wolbachia on sleep behavior of insect hosts are not well documented. In this study, we report that Wolbachia infection caused an increase of total sleep time in both male and female Drosophila melanogaster. The increase in sleep was associated with an increase in the number of nighttime sleep bouts or episodes, but not in sleep bout duration. Correspondingly, Wolbachia infection also reduced the arousal threshold of their fly hosts. However, neither circadian rhythm nor sleep rebound following deprivation was influenced by Wolbachia infection. Transcriptional analysis of the dopamine biosynthesis pathway revealed that two essential genes, Pale and Ddc, were significantly upregulated in Wolbachia-infected flies. Together, these results indicate that Wolbachia mediates the expression of dopamine related genes, and decreases the sleep quality of their insect hosts. Our findings help better understand the host-endosymbiont interactions and in particular the Wolbachia's impact on behaviors, and thus on ecology and evolution in insect hosts.},
}
@article {pmid29355963,
year = {2018},
author = {Brundrett, MC and Tedersoo, L},
title = {Evolutionary history of mycorrhizal symbioses and global host plant diversity.},
journal = {The New phytologist},
volume = {220},
number = {4},
pages = {1108-1115},
doi = {10.1111/nph.14976},
pmid = {29355963},
issn = {1469-8137},
mesh = {*Biodiversity ; *Biological Evolution ; Mycorrhizae/*physiology ; Plants/*microbiology ; Symbiosis/*physiology ; },
abstract = {Contents Summary 1108 I. Introduction 1108 II. Mycorrhizal plant diversity at global and local scales 1108 III. Mycorrhizal evolution in plants: a brief update 1111 IV. Conclusions and perspectives 1114 References 1114 SUMMARY: The majority of vascular plants are mycorrhizal: 72% are arbuscular mycorrhizal (AM), 2.0% are ectomycorrhizal (EcM), 1.5% are ericoid mycorrhizal and 10% are orchid mycorrhizal. Just 8% are completely nonmycorrhizal (NM), whereas 7% have inconsistent NM-AM associations. Most NM and NM-AM plants are nutritional specialists (e.g. carnivores and parasites) or habitat specialists (e.g. hydrophytes and epiphytes). Mycorrhizal associations are consistent in most families, but there are exceptions with complex roots (e.g. both EcM and AM). We recognize three waves of mycorrhizal evolution, starting with AM in early land plants, continuing in the Cretaceous with multiple new NM or EcM linages, ericoid and orchid mycorrhizas. The third wave, which is recent and ongoing, has resulted in root complexity linked to rapid plant diversification in biodiversity hotspots.},
}
@article {pmid31544655,
year = {2019},
author = {Agtuca, B and Stopka, SA and Tuleski, TR and Amaral, FPD and Evans, S and Liu, Y and Xu, D and Adele Monteiro, R and Koppenaal, DW and Paša-Tolić, L and Anderton, CR and Vertes, A and Stacey, G},
title = {In situ metabolomic analysis of Setaria viridis roots colonized by beneficial endophytic bacteria.},
journal = {Molecular plant-microbe interactions : MPMI},
volume = {},
number = {},
pages = {},
doi = {10.1094/MPMI-06-19-0174-R},
pmid = {31544655},
issn = {0894-0282},
abstract = {Over the past decades, crop yields have risen in parallel with increasing use of fossil-fuel derived nitrogen (N) fertilizers, but with concomitant negative impacts on climate and water resources. There is a need for more sustainable agricultural practices, and biological nitrogen fixation (BNF) could be part of the solution. A variety of nitrogen-fixing, epiphytic and endophytic plant growth promoting bacteria (PGPB) are known to stimulate plant growth. However, compared to the rhizobium-legume symbiosis, little mechanistic information is available as to how PGPB affect plant metabolism. Therefore, we investigated the metabolic changes in roots of the model grass species Setaria viridis upon endophytic colonization by Herbaspirillum seropedicae SmR1 (fix+) or a fix- mutant strain (SmR54), compared to uninoculated roots. Endophytic colonization of the root is highly localized and, hence, analysis of whole root segments dilutes the metabolic signature of those few cells impacted by the bacteria. Therefore, we utilized in situ laser ablation electrospray ionization mass spectrometry (LAESI-MS) to sample only those root segments at or adjacent to the sites of bacterial colonization. Metabolites involved in purine, zeatin, and riboflavin pathways were significantly more abundant in inoculated plants while metabolites indicative of nitrogen, starch, and sucrose metabolism were reduced in roots inoculated with the fix- strain or uninoculated, presumably due to N limitation. Interestingly, compounds, involved in indole-alkaloid biosynthesis were more abundant in the roots colonized by the fix- strain, perhaps reflecting a plant defense response.},
}
@article {pmid31543639,
year = {2019},
author = {Vijayaraghavan, S and Rishipathak, P and Hinduja, A},
title = {High-Fidelity Simulation versus Case-Based Discussion for Teaching Bradyarrhythmia to Emergency Medical Services Students.},
journal = {Journal of emergencies, trauma, and shock},
volume = {12},
number = {3},
pages = {176-178},
doi = {10.4103/JETS.JETS_115_18},
pmid = {31543639},
issn = {0974-2700},
abstract = {Introduction: Bradyarrhythmias are a common clinical finding yet can be life-threatening in certain situations. Accordingly, diagnosis and prompt intervention remain the cornerstone of effective management of bradyarrhythmia. The study compares the two methods by assessing improvement in knowledge acquisition using pretest, posttest, and satisfaction survey with the teaching pedagogy.<br><br>Materials and Methods: A randomized control trial of simulation-based teaching compared with case-based discussion was conducted among Postgraduate Diploma in Emergency Medical Services students. The students anonymously filled out pretest, posttest, and a satisfaction questionnaire composed of six statements in three domains (quality of instruction, debriefing, and overall satisfaction). The statements were rated using a 10-point scale. Test results were compared using t-test for equality of means of independent samples.<br><br>Results and Discussion: All 40 students selected completed all the steps of the study. Knowledge improvement from pretest to posttest was observed in both teaching methods derived using paired sample t-test (P < 0.05). However, no significant difference was observed while comparing improvement scores of posttest versus pretest between both the groups. Mean satisfaction score of simulation group was significantly higher at 8.40 compared to case-based group which was at 7.87. Satisfaction survey showed marked significance (P = 0.03) for simulation-based teaching.<br><br>Conclusion: As a single intervention, simulation-based teaching is superior to case-based discussion in terms of student satisfaction but remains similarly effective in terms of knowledge acquisition.},
}
@article {pmid31300924,
year = {2019},
author = {Fonseca-Romero, MA and Fornoni, J and Del-Val, E and Boege, K},
title = {Ontogenetic trajectories of direct and indirect defenses of myrmecophytic plants colonized either by mutualistic or opportunistic ant species.},
journal = {Oecologia},
volume = {190},
number = {4},
pages = {857-865},
doi = {10.1007/s00442-019-04469-y},
pmid = {31300924},
issn = {1432-1939},
support = {IN211314//Programa de Apoyo a Proyectos de Investigación e Innovación Tecnológica (UNAM)/ ; },
mesh = {Animals ; *Ants ; Plant Development ; Plant Leaves ; Plants ; Symbiosis ; },
abstract = {Myrmecophytic plants are expected to produce greater direct defenses when young and switch towards indirect defenses once they reach the size and vigor to produce enough rewards for their ant mutualists. The presence of opportunistic ant species, however, is likely to promote the variation in these ontogenetic trajectories. When plants do not obtain benefits from ants, they cannot rely on this indirect defense. Hence, the expression of direct defenses is expected to remain constant or even increase during the development of plants colonized by opportunistic ants, whereas a reduction in resource allocation to indirect defenses should be observed. To assess if myrmecophytic plants adjust their ontogenetic trajectories in defense as a function of the colonizing ant species, we estimated direct and indirect defenses at four ontogenetic stages of the myrmecophytic plant Vachellia hindsii colonized by either mutualistic or opportunistic ant partners. We report that cyanogenic potential decreased while leaf thickness and the production of sugar in extrafloral nectaries increased along plant development. The magnitude of these ontogenetic changes, however, varied as a function of the identity of the colonizing ants. As expected, when colonized by opportunistic ants, plants produced more direct defenses and reduced the production of rewards. We suggest that facultative changes in the expression of ontogenetic trajectories in direct and indirect defenses could be a mechanism to reduce the fitness costs associated with opportunistic interactions.},
}
@article {pmid31154510,
year = {2019},
author = {Hemrová, L and Kotilínek, M and Konečná, M and Paulič, R and Jersáková, J and Těšitelová, T and Knappová, J and Münzbergová, Z},
title = {Identification of drivers of landscape distribution of forest orchids using germination experiment and species distribution models.},
journal = {Oecologia},
volume = {190},
number = {2},
pages = {411-423},
doi = {10.1007/s00442-019-04427-8},
pmid = {31154510},
issn = {1432-1939},
support = {31-16-05677S//Grantová Agentura České Republiky/ ; RVO 67985939//Akademie Věd České Republiky/ ; },
mesh = {Animals ; Ecosystem ; Forests ; Germination ; *Mycorrhizae ; *Orchidaceae ; Symbiosis ; },
abstract = {The family of orchids involves a number of critically endangered species. Understanding of drivers of their landscape distribution could provide a valuable insight into their decline. Our objectives were to develop models predicting distribution of selected orchid species-four co-occurring forest orchid species, Cephalanthera rubra, Epipactis atrorubens, E. helleborine, and Neottia nidus-avis-at a landscape scale using a wide range of habitat characteristics. Subsequently, we compared the model predictions with species occurrence and the results of the field germination experiment while considering two germination stages-asymbiotic (early stage) and symbiotic. And finally, we attempted to identify possible drivers of species' landscape distribution (i.e., dispersal, availability of habitat patches, or fungal associates). We have discovered that different habitat characteristics determined the distribution of different orchids. The species also differed in terms of availability of suitable habitat patches and patch occupancy (the highest being E. atrorubens with 80%). Landscape distribution of the species was primarily restricted by the availability of fungal associates (the most important factor for C. rubra) and by the availability of suitable habitat patches (the most important in case of N. nidus-avis). Despite expected easy dispersal of spores, orchid distribution seems to be limited by the availability of fungal associates in the landscape. In contrast, the availability of orchid seeds does not seem to limit their distribution. These results can provide useful guidelines for conservation of the studied species.},
}
@article {pmid31102015,
year = {2019},
author = {Rekret, P and Maherali, H},
title = {Local adaptation to mycorrhizal fungi in geographically close Lobelia siphilitica populations.},
journal = {Oecologia},
volume = {190},
number = {1},
pages = {127-138},
doi = {10.1007/s00442-019-04412-1},
pmid = {31102015},
issn = {1432-1939},
support = {261300-2013//Natural Sciences and Engineering Research Council of Canada/ ; },
mesh = {Fungi ; *Lobelia ; *Mycorrhizae ; Phosphorus ; Plant Roots ; Soil ; Soil Microbiology ; Symbiosis ; },
abstract = {Mutualism between plants and arbuscular mycorrhizal (AM) fungi is common, and plant populations are expected to have adapted to the AM fungal communities occupying their roots. Tests of this hypothesis have frequently been done with plant populations that are tens to hundreds of kilometers apart. However, because AM fungal community composition differs at scales < 1 km, local adaptation of plant populations to AM fungi may occur at small spatial scales, but this prediction has not been tested. Furthermore, prior experiments do not often experimentally identify whether adaptation is related to specific mycorrhizal functions. To test for plant adaptation to AM fungal communities at small spatial scales, and whether adaptation is associated with the nutritional benefits that AM fungi provide to plants, we grew Lobelia siphilitica plants from two geographically close populations (1.4 km apart) in a greenhouse reciprocal transplant experiment with soil biota that either included (whole soil) or excluded AM fungi (microbial wash) at both low and high soil phosphorus availability. Though both plant populations responded positively to the presence of AM fungi in the whole soil biota treatment relative to the microbial wash treatment, the average growth response of plant populations to mycorrhizal fungi was highest when local populations were grown with local AM fungi. In addition, local adaptation was only observed in the presence of AM fungi at low phosphorus levels. Thus, local adaptation of plant populations to AM fungi is present at spatial scales that are much smaller than previously demonstrated and occurred primarily to enhance phosphorus acquisition.},
}
@article {pmid31062163,
year = {2019},
author = {Leong, FWS and Lam, WN and Tan, HTW},
title = {Digestive mutualism in a pitcher plant supports the monotonic rather than hump-shaped stress-gradient hypothesis model.},
journal = {Oecologia},
volume = {190},
number = {3},
pages = {523-534},
doi = {10.1007/s00442-019-04404-1},
pmid = {31062163},
issn = {1432-1939},
mesh = {Animals ; Larva ; Plant Leaves ; *Stress, Physiological ; *Symbiosis ; },
abstract = {The stress-gradient hypothesis (SGH) predicts that the strength and frequency of facilitative interactions increase monotonically with increasing environmental stress, but some empirical studies have found this decrease at extreme stress levels, suggesting a hump-shaped SGH instead. However, empirical studies of the SGH are often hindered by confounding resource and non-resource stress gradients. Nepenthes pitcher plants trap animal prey using modified-leaf pitfall traps which are also inhabited by organisms known as inquilines. Inquilines may assist pitchers in the digestion of trapped prey. This interaction is known as a digestive mutualism and is both mutualistic and facilitative by definition. Inquiline species may also facilitate each other via processing chain commensalisms. We used in vitro experiments to examine the isolated effect of resource stress on the outcomes of two facilitative interactions: (i) digestive mutualism-facilitation of pitcher nutrient sequestration by two inquiline dipteran larvae, culicids and phorids; (ii) processing chain commensalism-facilitation between these two inquiline taxa. The net nutritional benefit of phorids on N. gracilis was found to conform more to a monotonic rather than hump-shaped SGH model. However, the effect of culicids on N. gracilis and the effects of culicids and phorids on each other were weak. These findings provide compelling evidence that changes in facilitation along an isolated resource stress gradient conform to the predictions of the monotonic SGH model rather than that of the revised hump-shaped model, and highlight the importance of isolating stress gradients in empirical tests of the SGH.},
}
@article {pmid30953167,
year = {2019},
author = {Bontrager, M and Muir, CD and Angert, AL},
title = {Geographic variation in reproductive assurance of Clarkia pulchella.},
journal = {Oecologia},
volume = {190},
number = {1},
pages = {59-67},
doi = {10.1007/s00442-019-04390-4},
pmid = {30953167},
issn = {1432-1939},
support = {Discovery Grant//Natural Sciences and Engineering Research Council of Canada/ ; },
mesh = {*Clarkia ; Flowers ; Pollination ; Reproduction ; Seeds ; Symbiosis ; },
abstract = {Climate can affect plant populations through direct effects on physiology and fitness, and through indirect effects on their relationships with pollinating mutualists. We therefore expect that geographic variation in climate might lead to variation in plant mating systems. Biogeographic processes, such as range expansion, can also contribute to geographic patterns in mating system traits. We manipulated pollinator access to plants in eight sites spanning the geographic range of Clarkia pulchella to investigate geographic and climatic drivers of fruit production and seed set in the absence of pollinators (reproductive assurance). We examined how reproductive assurance and fruit production varied with the position of sites within the range of the species and with temperature and precipitation. We found that reproductive assurance in C. pulchella was greatest in populations in the northern part of the species' range and was not well explained by any of the climate variables that we considered. In the absence of pollinators, some populations of C. pulchella have the capacity to increase fruit production, perhaps through resource reallocation, but this response is climate dependent. Pollinators are important for reproduction in this species, and recruitment is sensitive to seed input. The degree of autonomous self-pollination that is possible in populations of this mixed-mating species may be shaped by historic biogeographic processes or variation in plant and pollinator community composition rather than variation in climate.},
}
@article {pmid30790444,
year = {2019},
author = {Xia, X and Zhang, J and Song, T and Lu, Y},
title = {Stimulation of Smithella-dominating propionate oxidation in a sediment enrichment by magnetite and carbon nanotubes.},
journal = {Environmental microbiology reports},
volume = {11},
number = {2},
pages = {236-248},
doi = {10.1111/1758-2229.12737},
pmid = {30790444},
issn = {1758-2229},
mesh = {Archaea/classification/genetics/isolation &amp; purification/metabolism ; Bacteria/classification/genetics/isolation &amp; purification/metabolism ; Butyrates/metabolism ; Deltaproteobacteria/genetics/isolation &amp; purification/*metabolism ; Ferrosoferric Oxide/*analysis/pharmacology ; Formates/pharmacology ; Geologic Sediments/*chemistry/*microbiology ; Hydrogen/pharmacology ; Methane/metabolism ; Nanotubes, Carbon/*analysis ; Oxidation-Reduction/drug effects ; Phylogeny ; Propionates/*metabolism ; RNA, Ribosomal, 16S/genetics ; Symbiosis ; },
abstract = {Recent studies have shown that application of conductive materials including magnetite and carbon nanotubes (CNTs) can promote the methanogenic decomposition of short-chain fatty acids and even more complex organic matter in anaerobic digesters and natural habitats. The linkage to microbial identity and the mechanisms, however, remain poorly understood. Here, we evaluate the effects of nanoscale magnetite (nanoFe3 O4) and multiwalled CNTs on the syntrophic oxidation of propionate in an enrichment obtained from lake sediment. The microbial populations were composed mainly of Smithella, Syntrophomonas, Methanosaeta, Methanosarcina and Methanoregula. In addition to acetate, butyrate was transiently accumulated indicating that propionate was oxidized by Smithella via the dismutation pathway and part of the leaked butyrate was oxidized by Syntrophomonas. Propionate oxidation and CH4 production were significantly accelerated in the presence of nanoFe3 O4 and CNTs. While propionate oxidation was suppressed upon H2 application and suspended completely upon formate application in the control, this suppressive effect was substantially compromised in the presence of nanoFe3 O4 and CNTs. The tests on hydrogenotrophic methanogenesis of a pure culture methanogen and of the enrichment culture without propionate showed negative effect by both materials. The positive effect of nanoFe3 O4 disappeared when it was insulated by surface-coating with silica. Observations made with fluorescence in situ hybridization and scanning electron microscope indicated the extensive formation of microbial cell-conductive material mixture aggregates. Our results suggest that direct interspecies electron transfer is likely activated by the conductive materials and operates in concert with H2 /formate-dependent electron transfer for syntrophic propionate oxidation in the sediment enrichment.},
}
@article {pmid30761773,
year = {2019},
author = {Sacristán-Soriano, O and Winkler, M and Erwin, P and Weisz, J and Harriott, O and Heussler, G and Bauer, E and West Marsden, B and Hill, A and Hill, M},
title = {Ontogeny of symbiont community structure in two carotenoid-rich, viviparous marine sponges: comparison of microbiomes and analysis of culturable pigmented heterotrophic bacteria.},
journal = {Environmental microbiology reports},
volume = {11},
number = {2},
pages = {249-261},
doi = {10.1111/1758-2229.12739},
pmid = {30761773},
issn = {1758-2229},
support = {705464//Marie Curie/United Kingdom ; },
mesh = {Animals ; Bacteria/chemistry/classification/genetics/metabolism ; Biodiversity ; Carotenoids ; DNA, Bacterial/genetics ; Heterotrophic Processes ; *Microbiota ; Phylogeny ; Porifera/*microbiology ; RNA, Ribosomal, 16S/genetics ; Seawater/microbiology ; Sequence Analysis, DNA ; Species Specificity ; *Symbiosis ; },
abstract = {Marine sponges harbour diverse communities of microbes. Mechanisms used to establish microbial symbioses in sponges are poorly understood, and the relative contributions of horizontal and vertical transmission are unknown for most species. We examined microbial communities in adults and larvae of carotenoid-rich Clathria prolifera and Halichondria bowerbanki from the mid-Atlantic region of the eastern United States. We sequenced microbiomes from larvae and their mothers and seawater (16S rRNA gene sequencing), and compared microbial community characteristics between species and ambient seawater. The microbial communities in sponges were significantly different than those found in seawater, and each species harboured a distinctive microbiome. Larval microbiomes exhibited significantly lower richness compared with adults, with both sponges appearing to transfer to larvae a particular subset of the adult microbiome. We also surveyed culturable bacteria isolated from larvae of both species. Due to conspicuous coloration of adults and larvae, we focused on pigmented heterotrophic bacteria. We found that the densities of bacteria, in terms of colony-forming units and pigmented heterotrophic bacteria, were higher in larvae than in seawater. We identified a common mode of transmission (vertical and horizontal) of microbes in both sponges that might differ between species.},
}
@article {pmid30673856,
year = {2019},
author = {Schweiger, JM and Kemnade, C and Bidartondo, MI and Gebauer, G},
title = {Light limitation and partial mycoheterotrophy in rhizoctonia-associated orchids.},
journal = {Oecologia},
volume = {189},
number = {2},
pages = {375-383},
doi = {10.1007/s00442-019-04340-0},
pmid = {30673856},
issn = {1432-1939},
support = {Ge 565/7-2//Deutsche Forschungsgemeinschaft/ ; },
mesh = {Carbon Isotopes ; *Mycorrhizae ; Nitrogen Isotopes ; *Orchidaceae ; Rhizoctonia ; Symbiosis ; },
abstract = {Partially mycoheterotrophic (PMH) plants obtain organic molecules from their mycorrhizal fungi in addition to carbon (C) fixed by photosynthesis. Some PMH orchids associated with ectomycorrhizal fungi have been shown to flexibly adjust the proportion of organic molecules obtained from fungi according to the habitat's light level. We hypothesise that Neottia ovata and Ophrys insectifera, two orchids associated with saprotrophic rhizoctonia fungi, are also able to increase uptake of organic molecules from fungi as irradiance levels decrease. We continuously measured light availability for individuals of N. ovata and O. insectifera at a grassland and a forest during orchid flowering and fruiting. We repeatedly sampled leaves of N. ovata, O. insectifera and autotrophic reference species for stable isotope natural abundances (δ13C, δ15N, δ2H, δ18O) and C and N concentrations. We found significant 13C enrichment in both orchids relative to autotrophic references at the forest but not the grassland, and significant 2H enrichment at both sites. The 13C enrichment in O. insectifera was linearly correlated with the habitat's irradiance levels. We conclude that both species can be considered as PMH and at least in O. insectifera, the degree of partial mycoheterotrophy can be fine-tuned according to light availability. However, exploitation of mycorrhizal fungi appears less flexible in saprotroph-associated orchids than in orchids associated with ectomycorrhizal fungi.},
}
@article {pmid30618212,
year = {2019},
author = {Zhang, H and Cai, Y and Li, X and Christie, P and Zhang, J and Gai, J},
title = {Temperature-mediated phylogenetic assemblage of fungal communities and local adaptation in mycorrhizal symbioses.},
journal = {Environmental microbiology reports},
volume = {11},
number = {2},
pages = {215-226},
doi = {10.1111/1758-2229.12729},
pmid = {30618212},
issn = {1758-2229},
mesh = {*Adaptation, Physiological ; Biodiversity ; Biomass ; DNA, Fungal/genetics ; DNA, Ribosomal/genetics ; Ecosystem ; *Mycobiome ; Mycorrhizae/classification/*physiology ; Phylogeny ; Plant Development ; Plant Roots/microbiology ; Plants/*microbiology ; Soil Microbiology ; *Symbiosis ; Temperature ; },
abstract = {Recent work demonstrates that habitat conditions exert striking effects on symbiont performance by mediating trade-offs in plants, AM fungi and environmental interactions. However, how local temperature conditions influence the functional diversity of mycorrhizal symbioses and the genetics of coexisting AM fungi at the local scale remain unclear. In the present study, we conducted a reciprocal inoculation experiment to explore the performance of sympatric associations against allopatric associations under contrasting temperatures and the AM fungal community in colonized roots. No local adaptation of plant biomass was found under both temperature conditions investigated, but a consistent local versus foreign effect was found in AM fungal performance. The temperature and the origin of the inoculum relative to the plant origin were important in explaining symbiotic function. Correspondingly, the community structure and Nearest Relatedness Index of the AM fungal community of the root symbiont varied with inoculum source, and assemblages with more closely related taxa led to a decline in plant biomass and stronger disequilibrium among AM fungi in roots. Our findings suggest that functional divergence exists in naturally coexisting communities of AM fungi from contrasting climatic origins, and fungal relatedness is an important driver of plant growth.},
}
@article {pmid30357527,
year = {2018},
author = {Parmentier, T and De Laender, F and Wenseleers, T and Bonte, D},
title = {Contrasting indirect effects of an ant host on prey-predator interactions of symbiotic arthropods.},
journal = {Oecologia},
volume = {188},
number = {4},
pages = {1145-1153},
pmid = {30357527},
issn = {1432-1939},
support = {BOF17/PDO/084//Bijzonder Onderzoeksfonds/ ; 253 PDM/16/099//KU Leuven/ ; },
mesh = {Animals ; *Ants ; *Arthropods ; Predatory Behavior ; *Spiders ; Symbiosis ; },
abstract = {Indirect interactions occur when a species affects another species by altering the density (density-mediated interactions) or influencing traits (trait-mediated interactions) of a third species. We studied variation in these two types of indirect interactions in a network of red wood ants and symbiotic arthropods living in their nests. We tested whether the ant workers indirectly affected survival of a symbiotic prey species (Cyphoderus albinus) by changing the density and/or traits of three symbiotic predators, i.e., Mastigusa arietina, Thyreosthenius biovatus and Stenus aterrimus, provoking, respectively, low, medium and high ant aggression. An ant nest is highly heterogeneous in ant worker density and the number of aggressive interactions towards symbionts increases with worker density. We, therefore, hypothesized that varying ant density could indirectly impact prey-predator interactions of the associated symbiont community. Ants caused trait-mediated indirect effects in all three prey-predator interactions, by affecting the prey capture rate of the symbiotic predators at different worker densities. Prey capture rate of the highly and moderately aggressed spider predators M. arietina and T. biovatus decreased with ant density, whereas the prey capture rate of the weakly aggressed beetle predator S. aterrimus increased. Ants also induced density-mediated indirect interactions as high worker densities decreased the survival rate of the two predatory spider species. These results demonstrate for the first time that a host can indirectly mediate the trophic interactions between associated symbionts. In addition, we show that a single host can induce opposing indirect effects depending on its degree of aggression towards the symbionts.},
}
@article {pmid30206689,
year = {2018},
author = {Leong, FWS and Lam, WN and Tan, HTW},
title = {A dipteran larva-pitcher plant digestive mutualism is dependent on prey resource digestibility.},
journal = {Oecologia},
volume = {188},
number = {3},
pages = {813-820},
pmid = {30206689},
issn = {1432-1939},
mesh = {Animals ; Larva ; *Plant Leaves ; *Symbiosis ; },
abstract = {Positive species interactions tend to be context dependent. However, it is difficult to predict how benefit in a mutualism changes in response to changing contexts. Nepenthes pitcher plants trap animal prey using leaf pitfall traps known as pitchers. Many specialized inquiline organisms inhibit these pitchers, and are known to facilitate the digestion of prey carcasses in them. Nepenthes gracilis traps diverse arthropod prey taxa, which are likely to differ greatly in the ease with which they may be digested, independently of inquilines, by plant enzymes. In this study, we used in vitro experiments to compare the nutritional benefit provided by phorid (scuttle fly) and culicid (mosquito) dipteran larvae to their host, N. gracilis, and to each other. The effects of phorids on N. gracilis nutrient sequestration were very variable, being positive for large prey which have low digestibility, but negative for small prey which are highly digestible. However, the effect of culicids on N. gracilis and the effects of culicids and phorids on each other were not significantly altered by prey type. These results show that a digestive mutualism is highly dependent on the digestibility of the resource-a context dependency that conforms well to the predictions of the stress-gradient hypothesis in facilitation research. Our findings have significant implications for many other digestive mutualisms, and also suggest that greater insights may be gained from the synthesis of concepts between the fields of mutualism and facilitation research.},
}
@article {pmid30105580,
year = {2018},
author = {Lim, RJY and Lam, WN and Tan, HTW},
title = {Novel pitcher plant-spider mutualism is dependent upon environmental resource abundance.},
journal = {Oecologia},
volume = {188},
number = {3},
pages = {791-800},
pmid = {30105580},
issn = {1432-1939},
mesh = {Animals ; *Diptera ; Nitrogen ; *Spiders ; Symbiosis ; },
abstract = {Positive species interactions are ubiquitous and crucial components of communities, but they are still not well incorporated into established ecological theories. The definitions of facilitation and mutualism overlap, and both are often context dependent. Many interactions that are facilitative under stressful conditions become competitive under more benign ones. This is known as the stress-gradient hypothesis, which is a specific case of context dependency. Stress can be further divided into resource and non-resource categories, but a better mechanistic understanding is necessary to improve the theory's predictions. We examined if two pitcher-dwelling crab spiders (Thomisidae), Thomisus nepenthiphilus and Misumenops nepenthicola, can facilitate nitrogen sequestration in their pitcher plant host, Nepenthes gracilis, by ambushing pitcher-visiting flies and dropping their carcasses into pitchers after consumption. This relationship is, by definition, both mutualistic and facilitative. Laboratory experiments found that both crab spiders increased prey-capture rates of N. gracilis. Nutrient analyses showed that both crab spiders also decreased per unit nitrogen yield of prey. Using experiment duration as a proxy of prey-resource availability, we constructed a mechanistic conceptual model of nutritional benefit. The nutritional benefit received by N. gracilis from T. nepenthiphilus decreases with increasing levels of the limiting resource in the environment (i.e., decreasing levels of resource stress). Our findings suggest that any nutritional mutualism that increases the quantity of resource capture (e.g. number of prey individuals) but decreases the quality of the captured resource (e.g. nitrogen content of individual prey) will necessarily conform to the resource-based predictions of the stress gradient hypothesis.},
}
@article {pmid29943143,
year = {2018},
author = {terHorst, CP and Wirth, C and Lau, JA},
title = {Genetic variation in mutualistic and antagonistic interactions in an invasive legume.},
journal = {Oecologia},
volume = {188},
number = {1},
pages = {159-171},
doi = {10.1007/s00442-018-4211-6},
pmid = {29943143},
issn = {1432-1939},
support = {1312490//Division of Mathematical Sciences/ ; 1559105//Division of Ocean Sciences/ ; 0918963//Division of Environmental Biology/ ; 1257756//Division of Environmental Biology/ ; },
mesh = {*Fabaceae ; Genetic Variation ; Plant Development ; *Rhizobium ; Symbiosis ; },
abstract = {Mutualists may play an important role in invasion success. The ability to take advantage of novel mutualists or survive and reproduce despite a lack of mutualists may facilitate invasion by those individuals with such traits. Here, we used two greenhouse studies to examine how soil microbial communities in general and mutualistic rhizobia in particular affect the performance of a legume species (Medicago polymorpha) that has invaded five continents. We performed two plant growth experiments with Medicago polymorpha, inoculating them with soil slurries in one experiment or rhizobial cultures in another experiment. For both experiments, we compared the growth of Medicago in competition with conspecific or heterospecific plants and examined variation among plant genotypes collected from the native and introduced ranges. We found that all genotypes experienced similar increases in biomass and formed more nodules that house rhizobia bacteria when inoculated with soil from a previously invaded site, compared to uninoculated plants or plants inoculated with soil from uninvaded and low invasion sites. In a second experiment, plants inoculated with rhizobia generally produced more biomass, had greater tolerance to interspecific competition, and had greater effects on competitor biomass than uninoculated plants. However, plant genotypes collected from the native range benefited more from rhizobia and were less tolerant of competition relative to genotypes collected from the introduced range. In the introduced range, compatible mutualists may not be readily available but competition is intense, causing Medicago to evolve to benefit less from interactions with rhizobia mutualists, while simultaneously becoming more tolerant of competition.},
}
@article {pmid29869019,
year = {2018},
author = {Kersch-Becker, MF and Grisolia, BB and Campos, MJO and Romero, GQ},
title = {The role of spider hunting mode on the strength of spider-plant mutualisms.},
journal = {Oecologia},
volume = {188},
number = {1},
pages = {213-222},
doi = {10.1007/s00442-018-4170-y},
pmid = {29869019},
issn = {1432-1939},
support = {313955/2014-0//Conselho Nacional de Desenvolvimento Científico e Tecnológico/ ; 400892/2014-6//Conselho Nacional de Desenvolvimento Científico e Tecnológico/ ; 2016/01209-9//Fundação de Amparo à Pesquisa do Estado de São Paulo/ ; },
mesh = {Animals ; Ecosystem ; Plants ; Predatory Behavior ; *Spiders ; Symbiosis ; },
abstract = {The strength and outcome of mutualistic interactions can be highly dependent on the combination of traits of the species involved. Distinct foraging strategies (e.g., hunting mode) of mutualistic predators may cause predator-prey interactions to vary, potentially affecting the strength of trophic cascades. We evaluate the causes of variation in the strength of spider-plant mutualisms by focusing on contrasting hunting modes of two spiders: an actively hunting lynx spider (Peucetia sp.) and a sit-and-wait crab spider (Misumenops argenteus). We manipulated spider species composition by assigning each plant to one of the following treatments: (1) no spiders; (2) sit-and-wait spiders only; (3) actively hunting spiders only; (4) actively hunting + sit-and-wait spiders. We then examined the independent and interactive effects of spider species on floral herbivory and fitness of the glandular trichome-bearing plant, Trichogoniopsis adenantha (Asteraceae). Both spider species increased plant fitness by suppressing herbivores and increasing ovary fertilization, but the overall net benefit of spiders was contingent on spider hunting mode. Sit-and-wait spiders promoted stronger positive cascading effects compared to actively hunting spiders. The combination of spider species suppressed herbivores in an additive manner; their combined impact on plant fitness, however, was lower than expected, suggesting that the inter-specific interaction between spiders is slightly antagonistic. Thus, both spider species combined weakened the strength of this spider-plant mutualism. Our findings offer a general framework for understanding the critical role of predator foraging mode in trophic cascades.},
}
@article {pmid29521443,
year = {2018},
author = {Ankrah, NYD and Douglas, AE},
title = {Nutrient factories: metabolic function of beneficial microorganisms associated with insects.},
journal = {Environmental microbiology},
volume = {20},
number = {6},
pages = {2002-2011},
doi = {10.1111/1462-2920.14097},
pmid = {29521443},
issn = {1462-2920},
support = {IOS-1354743//National Science Foundation/International ; },
mesh = {Animals ; Bacteria/*metabolism ; Insecta/*microbiology ; Nutrients/*metabolism ; *Symbiosis ; },
abstract = {Many symbiotic microorganisms in animals, including insects, have parallels to microbial nutrient factories of biotechnology: just as the metabolism of individual microorganisms and microbial communities is modified by biotechnologists to produce specific nutrients, so the many insect-associated microorganisms synthesize specific nutrients that support the sustained growth and reproduction of their animal host. Three broad metabolic functions are mediated by insect-associated microorganisms: (i) fermentation of dietary constituents, releasing products that contribute to host carbon and energy metabolism; (ii) overproduction of nutrients, notably essential amino acids, required by the host and (iii) recycling of host waste metabolites. In many systems, the nutrients that are released from living microbial cells have been identified, with evidence for metabolite cross-feeding and shared metabolic pathways both among different microbial taxa and between microorganisms and the host. However, the flux of nutrients from microbial cells to host has rarely been quantified; our understanding of the processes that regulate nutrient transfer is fragmentary; and the scale and mechanism of metabolic adaptations of microorganisms to host nutritional demand are largely unknown. Recent advances in metabolic, microscopical and modelling techniques offer excellent opportunities to resolve these outstanding issues, with insights that can contribute to the effective design of nutrient factories for biotechnological applications.},
}
@article {pmid29488306,
year = {2018},
author = {López-Lara, IM and Nogales, J and Pech-Canul, Á and Calatrava-Morales, N and Bernabéu-Roda, LM and Durán, P and Cuéllar, V and Olivares, J and Alvarez, L and Palenzuela-Bretones, D and Romero, M and Heeb, S and Cámara, M and Geiger, O and Soto, MJ},
title = {2-Tridecanone impacts surface-associated bacterial behaviours and hinders plant-bacteria interactions.},
journal = {Environmental microbiology},
volume = {20},
number = {6},
pages = {2049-2065},
doi = {10.1111/1462-2920.14083},
pmid = {29488306},
issn = {1462-2920},
support = {BIO2010-18005//Spanish Ministry for Economy and Competitiveness/International ; BIO2013-42801-P//Spanish Ministry for Economy and Competitiveness/International ; CVI-03541//Consejería de Economía, Innovación Ciencia y Empleo, Junta de Andalucía/International ; //ERDF funds/International ; 153998//CONACyT-Mexico/International ; MR/N501852/1//JPI-AMR-Medical Research Council/International ; //Spanish Ministry for Education and Science/International ; MR/N501852/1//Medical Research Council/United Kingdom ; },
mesh = {Bacterial Proteins/genetics/*metabolism ; Biofilms/drug effects ; Gene Expression Profiling ; Gene Expression Regulation, Bacterial ; Ketones/*metabolism/*pharmacology ; Medicago sativa/*microbiology ; Mutation ; Phenotype ; Sinorhizobium meliloti/*drug effects/genetics/*metabolism ; Symbiosis ; },
abstract = {Surface motility and biofilm formation are behaviours which enable bacteria to infect their hosts and are controlled by different chemical signals. In the plant symbiotic alpha-proteobacterium Sinorhizobium meliloti, the lack of long-chain fatty acyl-coenzyme A synthetase activity (FadD) leads to increased surface motility, defects in biofilm development and impaired root colonization. In this study, analyses of lipid extracts and volatiles revealed that a fadD mutant accumulates 2-tridecanone (2-TDC), a methylketone (MK) known as a natural insecticide. Application of pure 2-TDC to the wild-type strain phenocopies the free-living and symbiotic behaviours of the fadD mutant. Structural features of the MK determine its ability to promote S. meliloti surface translocation, which is mainly mediated by a flagella-independent motility. Transcriptomic analyses showed that 2-TDC induces differential expression of iron uptake, redox and stress-related genes. Interestingly, this MK also influences surface motility and impairs biofilm formation in plant and animal pathogenic bacteria. Moreover, 2-TDC not only hampers alfalfa nodulation but also the development of tomato bacterial speck disease. This work assigns a new role to 2-TDC as an infochemical that affects important bacterial traits and hampers plant-bacteria interactions by interfering with microbial colonization of plant tissues.},
}
@article {pmid29305657,
year = {2018},
author = {Clark, RE and Singer, MS},
title = {Keystone mutualism strengthens top-down effects by recruiting large-bodied ants.},
journal = {Oecologia},
volume = {186},
number = {3},
pages = {601-610},
pmid = {29305657},
issn = {1432-1939},
support = {1404177//Division of Environmental Biology/International ; },
mesh = {Animals ; *Ants ; Connecticut ; Food Chain ; Herbivory ; Predatory Behavior ; Symbiosis ; },
abstract = {Determining the impacts of mutualistic interactions and predator diversity on food webs are two important goals in community ecology. In this study, we examined how predator community variation mediates the strength of top-down effects in the presence and absence of mutualistic interactions. We examined the impacts of predatory ant species that simultaneously prey on leaf-chewing herbivores (Lepidoptera) and engage in food-for-protection mutualisms with sap-feeding herbivores (Hemiptera) in the lower canopy of Connecticut forests. In this 2-year study, we examined three hypothetical mechanisms by which mutualisms can alter the top-down effects of ants: (1) sap feeders increase ant abundance, thus strengthening predatory effects; (2) sap feeders increase the relative abundance of a species that has stronger predatory effects; and (3) changes to predator diversity (species richness) are caused by sap feeders mediating top-down effects of the ant community. Experiments revealed that host plants occupied by sap feeders favored large-bodied ant species in the genus Camponotus, but there were no changes to community-wide ant abundance or ant species richness. Fitting predictions of predation strength based on the functional trait of body size, large-bodied Camponotus suppressed caterpillars and reduced leaf herbivory. This work shows that the ant-hemipteran mutualism, which has been characterized as a keystone interaction, can generate strong top-down effects on leaf-chewing herbivores and herbivory via increasing the relative abundance of species with functional traits relevant to predation, such as body size. Therefore, the emergence of specific ants as keystone predators in a community can be contingent upon their mutualism with sap-feeding Hemiptera.},
}
@article {pmid29247290,
year = {2018},
author = {Ibarra-Isassi, J and Oliveira, PS},
title = {Indirect effects of mutualism: ant-treehopper associations deter pollinators and reduce reproduction in a tropical shrub.},
journal = {Oecologia},
volume = {186},
number = {3},
pages = {691-701},
pmid = {29247290},
issn = {1432-1939},
support = {306115/2013-1//Brazilian Research Council (CNPq)/International ; 2014/23141-1//Fundação de Amparo à Pesquisa do Estado de São Paulo/International ; 2014/12486-8//Fundação de Amparo à Pesquisa do Estado de São Paulo/International ; },
mesh = {Animals ; *Ants ; Bees ; Brazil ; Flowers ; *Hemiptera ; Pollination ; Reproduction ; Symbiosis ; },
abstract = {Animal-pollinated plants can be susceptible to changes in pollinator availability. Honeydew-producing treehoppers frequently occur on inflorescences, potentially enhancing ant-mediated negative effects on pollination services. However, the effect of ant-attended, honeydew-producing insects on plant reproduction remains uncertain. We recorded the abundance of treehoppers and ants on Byrsonima intermedia (Malpighiaceae), and monitored floral visitors in a Brazilian cerrado savanna. We manipulated the presence of ants and ant-treehopper associations on inflorescences to assess their effect on pollination and fruit formation. We used dried ants pinned to inflorescences to evaluate the effect of ant presence and ant identity on potential pollinators. Results show that the presence of treehoppers increases ant abundance on flowers and disrupts pollination by oil-collecting bees, decreasing the frequency and duration of floral visits and reducing fruit and seed set. Treehopper herbivory has no direct effect on fruit or seed production, which are independent of treehopper density. Pinned ants promote avoidance by floral visitors, reducing the number of visits. Ant identity mediates visitation decisions, with Ectatomma brunneum causing greater avoidance by floral visitors than Camponotus rufipes. Field videos show that pollinating bees are harassed by ants near flowers, prompting avoidance behavior by the bees. This is the first demonstration of indirect effects by honeydew-gathering ants, via disrupted pollination, on plant reproduction in tropical cerrado savanna. Our results highlight the importance of studying other interactions near flowers, in addition to just observing pollinators, for a proper understanding of plant reproduction.},
}
@article {pmid31542229,
year = {2019},
author = {Al-Khafaji, AM and Armstrong, SD and Varotto Boccazzi, I and Gaiarsa, S and Sinha, A and Li, Z and Sassera, D and Carlow, CKS and Epis, S and Makepeace, BL},
title = {Rickettsia buchneri, symbiont of the deer tick Ixodes scapularis, can colonise the salivary glands of its host.},
journal = {Ticks and tick-borne diseases},
volume = {},
number = {},
pages = {101299},
doi = {10.1016/j.ttbdis.2019.101299},
pmid = {31542229},
issn = {1877-9603},
abstract = {Vertically-transmitted bacterial symbionts are widespread in ticks and have manifold impacts on the epidemiology of tick-borne diseases. For instance, they may provide essential nutrients to ticks, affect vector competence, induce immune responses in vertebrate hosts, or even evolve to become vertebrate pathogens. The deer or blacklegged tick Ixodes scapularis harbours the symbiont Rickettsia buchneri in its ovarian tissues. Here we show by molecular, proteomic and imaging methods that R. buchneri is also capable of colonising the salivary glands of wild I. scapularis. This finding has important implications for the diagnosis of rickettsial infections and for pathogen-symbiont interactions in this notorious vector of Lyme borreliosis.},
}
@article {pmid31541734,
year = {2019},
author = {Kolbert, Z and Barroso, JB and Brouquisse, R and Corpas, FJ and Gupta, KJ and Lindermayr, C and Loake, GJ and Palma, JM and Petřivalský, M and Wendehenne, D and Hancock, JT},
title = {A forty year journey: The generation and roles of NO in plants.},
journal = {Nitric oxide : biology and chemistry},
volume = {},
number = {},
pages = {},
doi = {10.1016/j.niox.2019.09.006},
pmid = {31541734},
issn = {1089-8611},
abstract = {In this year there is the 40th anniversary of the first publication of plant nitric oxide (NO) emission by Lowell Klepper. In the decades since then numerous milestone discoveries have revealed that NO is a multifunctional molecule in plant cells regulating both plant development and stress responses. Apropos of the anniversary, these authors aim to review and discuss the developments of past concepts in plant NO research related to NO metabolism, NO signaling, NO's action in plant growth and in stress responses and NO's interactions with other reactive compounds. Despite the long-lasting research efforts and the accumulating experimental evidences numerous questions are still needed to be answered, thus future challenges and research directions have also been drawn up.},
}
@article {pmid31541152,
year = {2019},
author = {Cheng, CY and Chang, SL and Lin, IT and Yao, MC},
title = {Abundant and diverse Tetrahymena species living in the bladder traps of aquatic carnivorous Utricularia plants.},
journal = {Scientific reports},
volume = {9},
number = {1},
pages = {13669},
doi = {10.1038/s41598-019-50123-1},
pmid = {31541152},
issn = {2045-2322},
abstract = {Ciliates are unicellular eukaryotes known for their cellular complexity and wide range of natural habitats. How they adapt to their niches and what roles they play in ecology remain largely unknown. The genus Tetrahymena is among the best-studied groups of ciliates and one particular species, Tetrahymena thermophila, is a well-known laboratory model organism in cell and molecular biology, making it an excellent candidate for study in protist ecology. Here, based on cytochrome c oxidase subunit I (COX1) gene barcoding, we identify a total of 19 different putative Tetrahymena species and two closely related Glaucoma lineages isolated from distinct natural habitats, of which 13 are new species. These latter include 11 Tetrahymena species found in the bladder traps of Utricularia plants, the most species-rich and widely distributed aquatic carnivorous plant, thus revealing a previously unknown but significant symbiosis of Tetrahymena species living among the microbial community of Utricularia bladder traps. Additional species were collected using an artificial trap method we have developed. We show that diverse Tetrahymena species may live even within the same habitat and that their populations are highly dynamic, suggesting that the diversity and biomass of species worldwide is far greater than currently appreciated.},
}
@article {pmid31537840,
year = {2019},
author = {Catanzaro, JR and Strauss, JD and Bielecka, A and Porto, AF and Lobo, FM and Urban, A and Schofield, WB and Palm, NW},
title = {IgA-deficient humans exhibit gut microbiota dysbiosis despite secretion of compensatory IgM.},
journal = {Scientific reports},
volume = {9},
number = {1},
pages = {13574},
doi = {10.1038/s41598-019-49923-2},
pmid = {31537840},
issn = {2045-2322},
abstract = {Immunoglobulin A is the dominant antibody isotype found in mucosal secretions and enforces host-microbiota symbiosis in mice, yet selective IgA-deficiency (sIgAd) in humans is often described as asymptomatic. Here, we determined the effects of IgA deficiency on human gut microbiota composition and evaluated the possibility that mucosal secretion of IgM can compensate for a lack of secretory IgA. We used 16S rRNA gene sequencing and bacterial cell sorting to evaluate gut microbiota composition and taxa-specific antibody coating of the gut microbiota in 15 sIgAd subjects and matched controls. Despite the secretion of compensatory IgM into the gut lumen, sIgAd subjects displayed an altered gut microbiota composition as compared to healthy controls. These alterations were characterized by a trend towards decreased overall microbial diversity as well as significant shifts in the relative abundances of specific microbial taxa. While secretory IgA in healthy controls targeted a defined subset of the microbiota via high-level coating, compensatory IgM in sIgAd subjects showed less specificity than IgA and bound a broader subset of the microbiota. We conclude that IgA plays a critical and non-redundant role in controlling gut microbiota composition in humans and that secretory IgA has evolved to maintain a diverse and stable gut microbial community.},
}
@article {pmid31537652,
year = {2019},
author = {Whittaker, DJ and Slowinski, SP and Greenberg, JM and Alian, O and Winters, AD and Ahmad, MM and Burrell, MJE and Soini, HA and Novotny, MV and Ketterson, ED and Theis, KR},
title = {Experimental evidence that symbiotic bacteria produce chemical cues in a songbird.},
journal = {The Journal of experimental biology},
volume = {},
number = {},
pages = {},
doi = {10.1242/jeb.202978},
pmid = {31537652},
issn = {1477-9145},
abstract = {Symbiotic microbes that inhabit animal scent glands can produce volatile compounds used as chemical signals by the host animal. Though several studies have demonstrated correlations between scent gland bacterial community structure and host animal odour profiles, none have systematically demonstrated a causal relationship. In birds, volatile compounds in preen oil secreted by the uropygial gland serve as chemical cues and signals. Here we test whether manipulating the uropygial gland microbial community affects chemical profiles in the dark-eyed junco (Junco hyemalis). We found an effect of antibiotic treatment targeting the uropygial gland on both bacterial and volatile profiles. In a second study, we cultured bacteria from junco preen oil, and found that all the cultivars produced at least one volatile compound common in junco preen oil, and that most cultivars produced multiple preen oil volatiles. In both studies, we identified experimentally generated patterns in specific volatile compounds previously shown to predict junco reproductive success. Together, our data provide experimental support for the hypothesis that symbiotic bacteria produce behaviourally relevant volatile compounds within avian chemical cues and signals.},
}
@article {pmid31534844,
year = {2019},
author = {May, A and Narayanan, S and Alcock, J and Varsani, A and Maley, C and Aktipis, A},
title = {Kombucha: a novel model system for cooperation and conflict in a complex multi-species microbial ecosystem.},
journal = {PeerJ},
volume = {7},
number = {},
pages = {e7565},
doi = {10.7717/peerj.7565},
pmid = {31534844},
issn = {2167-8359},
abstract = {Kombucha, a fermented tea beverage with an acidic and effervescent taste, is composed of a multispecies microbial ecosystem with complex interactions that are characterized by both cooperation and conflict. In kombucha, a complex community of bacteria and yeast initiates the fermentation of a starter tea (usually black or green tea with sugar), producing a biofilm that covers the liquid over several weeks. This happens through several fermentative phases that are characterized by cooperation and competition among the microbes within the kombucha solution. Yeast produce invertase as a public good that enables both yeast and bacteria to metabolize sugars. Bacteria produce a surface biofilm which may act as a public good providing protection from invaders, storage for resources, and greater access to oxygen for microbes embedded within it. The ethanol and acid produced during the fermentative process (by yeast and bacteria, respectively) may also help to protect the system from invasion by microbial competitors from the environment. Thus, kombucha can serve as a model system for addressing important questions about the evolution of cooperation and conflict in diverse multispecies systems. Further, it has the potential to be artificially selected to specialize it for particular human uses, including the development of antimicrobial ecosystems and novel materials. Finally, kombucha is easily-propagated, non-toxic, and inexpensive, making it an excellent system for scientific inquiry and citizen science.},
}
@article {pmid31534701,
year = {2019},
author = {Garcia, JR and Larsen, TJ and Queller, DC and Strassmann, JE},
title = {Fitness costs and benefits vary for two facultative Burkholderia symbionts of the social amoeba, Dictyostelium discoideum.},
journal = {Ecology and evolution},
volume = {9},
number = {17},
pages = {9878-9890},
doi = {10.1002/ece3.5529},
pmid = {31534701},
issn = {2045-7758},
abstract = {Hosts and their associated microbes can enter into different relationships, which can range from mutualism, where both partners benefit, to exploitation, where one partner benefits at the expense of the other. Many host-microbe relationships have been presumed to be mutualistic, but frequently only benefits to the host, and not the microbial symbiont, have been considered. Here, we address this issue by looking at the effect of host association on the fitness of two facultative members of the Dictyostelium discoideum microbiome (Burkholderia agricolaris and Burkholderia hayleyella). Using two indicators of bacterial fitness, growth rate and abundance, we determined the effect of D. discoideum on Burkholderia fitness. In liquid culture, we found that D. discoideum amoebas lowered the growth rate of both Burkholderia species. In soil microcosms, we tracked the abundance of Burkholderia grown with and without D. discoideum over a month and found that B. hayleyella had larger populations when associating with D. discoideum while B. agricolaris was not significantly affected. Overall, we find that both B. agricolaris and B. hayleyella pay a cost to associate with D. discoideum, but B. hayleyella can also benefit under some conditions. Understanding how fitness varies in facultative symbionts will help us understand the persistence of host-symbiont relationships.<br><br>OPEN RESEARCH BADGES: This article has earned an Open Data Badge for making publicly available the digitally-shareable data necessary to reproduce the reported results. The data is available at https://openscholarship.wustl.edu/data/15/.},
}
@article {pmid31534383,
year = {2019},
author = {Hosie, AM and Fromont, J and Munyard, K and Jones, DS},
title = {Description of a new species of Membranobalanus (Crustacea, Cirripedia) from southern Australia.},
journal = {ZooKeys},
volume = {873},
number = {},
pages = {25-42},
doi = {10.3897/zookeys.873.35421},
pmid = {31534383},
issn = {1313-2989},
abstract = {A new species of sponge-inhabiting barnacle, Membranobalanus porphyrophilussp. nov., is described herein. This species can be distinguished from all other congeners by a combination of characters, in particular by the shapes of the tergum and scutum and the armament of the cirri. COI sequence data from the type specimens have been lodged with GenBank and a morphological key to the species of Membranobalanus is provided to aid future research. The host of the new species is the southern Australian endemic demosponge Spheciospongia purpurea. The new species of barnacle is thought to be host species specific.},
}
@article {pmid31529916,
year = {2016},
author = {Titov, VN and Parchimovitch, RM},
title = {[The phylogenetic theory of general pathology. The becoming of function of at mitochondria at symbiosis of bacterial cells and archaea. Inconsistency of Randle cycle, regulation metabolism of fatty acids and glucose by insulin.].},
journal = {Klinicheskaia laboratornaia diagnostika},
volume = {61},
number = {7},
pages = {388-396},
doi = {10.18821/0860-2084-2016-61-7-388-396},
pmid = {31529916},
issn = {0869-2084},
abstract = {The implementation of Randle rule is not a cycle; fatty acids C4 - ketone bodies at interrelationships with glucose metabolite - pyruvate regulate production of mitochondria of acetyl-KoA by induction of substrate and its conversion in Krebs cycle, reactions of respiratory chain, oxidative phosphorylation and formation of ATP. In phylogenesis, the early substrate for formation of ATP by mitochondria is acetyl-KoA from C4 fatty acids 4; this is alternative A of induction by substrate adopted from archaea. The alternative B of induction in bacteria is based on synthesis of acetyl-KoA by mitohondria from pyruvate developed in cytosol from exogenous glucose. The insulin is late activator of absorption by glucose cells in phylogenesis; using induction by substrate, insulin inhibits absorption of fatty acids by cells and specifically activates absorption of glucose by them. The insulin activates absorption of glucose only by insulin-dependent cells by force of decreasing of &quot;bioavailability&quot; of fatty acids. These cells are preferred to be metabolize by mitochondria from times of archaea. The insulin, blocking lipolysis in insulin-dependent adipocytes &quot;forces&quot; mitochondria, instead of formation of acetyl-KoA from fatty acids, to produce it from pyruvate at activation of glycolysis and pyruvate-dehydrogenased complex. Under effect of insulin, mitochondria form acetyl-KoA and synthesize ATP from oleic mono-saturated fatty acids but not from palmitic saturated fatty acids. The kinetic parameters of second reaction and formation of ATP per unit of time (effectiveness) are much higher than in first reaction. The effectiveness of i9mplementation of alternative A in synthesis of ATP, kinetic parameters of production of acetyl-KoA in mitochondria in alternative A are more effective than in case of alternative B and metabolic conversion of glucose. The syndrome of resistance to insulin is, at the first place, pathology of metabolism of fatty acids and only in the second place metabolism of glucose. The incapacity of insulin to block lipolysis in the phylogenetically earlier visceral fatty cells is the basis of resistance.},
}
@article {pmid30830394,
year = {2018},
author = {Farag, MA and Maamoun, AA and Meyer, A and Wessjohann, LA},
title = {Salicylic acid and its derivatives elicit the production of diterpenes and sterols in corals and their algal symbionts: a metabolomics approach to elicitor SAR.},
journal = {Metabolomics : Official journal of the Metabolomic Society},
volume = {14},
number = {10},
pages = {127},
doi = {10.1007/s11306-018-1416-y},
pmid = {30830394},
issn = {1573-3890},
mesh = {Animals ; Anthozoa/chemistry/*metabolism ; Diterpenes/chemistry/*metabolism ; *Metabolomics ; Multivariate Analysis ; Salicylic Acid/*chemistry/*metabolism ; Sterols/*biosynthesis/chemistry ; Structure-Activity Relationship ; *Symbiosis ; },
abstract = {INTRODUCTION: The production of marine drugs in its normal habitats is often low and depends greatly on ecological conditions. Chemical synthesis of marine drugs is not economically feasible owing to their complex structures. Biotechnology application via elicitation represents a promising tool to enhance metabolites yield that has yet to be explored in soft corals.<br><br>OBJECTIVES: Study the elicitation impact of salicylic acid (SA) and six analogues in addition to a systemic acquired resistance inducer on secondary metabolites accumulation in the soft coral Sarcophyton ehrenbergi along with the symbiont zooxanthellae and if SA elicitation effect is extended to other coral species S. glaucum and Lobophyton pauciliforum.<br><br>METHODS: Post elicitation in the three corals and zooxanthella, metabolites were extracted and analyzed via UHPLC-MS coupled with chemometric tools.<br><br>RESULTS: Multivariate data analysis of the UHPLC-MS data set revealed clear segregation of SA, amino-SA, and acetyl-SA elicited samples. An increased level ca. 6- and 8-fold of the diterpenes viz., sarcophytonolide I, sarcophine and a C28-sterol, was observed in SA and amino-SA groups, respectively. Post elicitation, the level of diepoxy-cembratriene increased 1.5-fold and 2.4-fold in 1 mM SA, and acetyl-SA (aspirin) treatment groups, respectively. S. glaucum and Lobophyton pauciliforum showed a 2-fold increase of diepoxy-cembratriene levels.<br><br>CONCLUSION: These results suggest that SA could function as a general and somewhat selective diterpene inducing signaling molecule in soft corals. Structural consideration reveals initial structure-activity relationship (SAR) in SA derivatives that seem important for efficient diterpene and sterol elicitation.},
}
@article {pmid30150232,
year = {2018},
author = {Tsao, YF and Taylor, VL and Kala, S and Bondy-Denomy, J and Khan, AN and Bona, D and Cattoir, V and Lory, S and Davidson, AR and Maxwell, KL},
title = {Phage Morons Play an Important Role in Pseudomonas aeruginosa Phenotypes.},
journal = {Journal of bacteriology},
volume = {200},
number = {22},
pages = {},
pmid = {30150232},
issn = {1098-5530},
support = {MOP-136845//CIHR/Canada ; XNE-86943//CIHR/Canada ; },
mesh = {Animals ; Drosophila melanogaster/microbiology ; *Genes, Viral ; Host-Pathogen Interactions ; Lysogeny ; *Phenotype ; Prophages/*genetics ; Pseudomonas Infections/microbiology ; Pseudomonas Phages/*genetics/physiology ; Pseudomonas aeruginosa/pathogenicity/*virology ; Symbiosis ; Virulence ; Virulence Factors/*genetics ; },
abstract = {The viruses that infect bacteria, known as phages, play a critical role in controlling bacterial populations in many diverse environments, including the human body. This control stems not only from phages killing bacteria but also from the formation of lysogens. In this state, the phage replication cycle is suppressed, and the phage genome is maintained in the bacterial cell in a form known as a prophage. Prophages often carry genes that benefit the host bacterial cell, since increasing the survival of the host cell by extension also increases the fitness of the prophage. These highly diverse and beneficial phage genes, which are not required for the life cycle of the phage itself, have been referred to as &quot;morons,&quot; as their presence adds &quot;more on&quot; the phage genome in which they are found. While individual phage morons have been shown to contribute to bacterial virulence by a number of different mechanisms, there have been no systematic investigations of their activities. Using a library of phages that infect two different clinical isolates of P. aeruginosa, PAO1 and PA14, we compared the phenotypes imparted by the expression of individual phage morons. We identified morons that inhibit twitching and swimming motilities and observed an inhibition of the production of virulence factors such as rhamnolipids and elastase. This study demonstrates the scope of phage-mediated phenotypic changes and provides a framework for future studies of phage morons.IMPORTANCE Environmental and clinical isolates of the bacterium Pseudomonas aeruginosa frequently contain viruses known as prophages. These prophages can alter the virulence of their bacterial hosts through the expression of nonessential genes known as &quot;morons.&quot; In this study, we identified morons in a group of Pseudomonas aeruginosa phages and characterized the effects of their expression on bacterial behaviors. We found that many morons confer selective advantages for the bacterial host, some of which correlate with increased bacterial virulence. This work highlights the symbiotic relationship between bacteria and prophages and illustrates how phage morons can help bacteria adapt to different selective pressures and contribute to human diseases.},
}
@article {pmid29349810,
year = {2018},
author = {Senovilla, M and Castro-Rodríguez, R and Abreu, I and Escudero, V and Kryvoruchko, I and Udvardi, MK and Imperial, J and González-Guerrero, M},
title = {Medicago truncatula copper transporter 1 (MtCOPT1) delivers copper for symbiotic nitrogen fixation.},
journal = {The New phytologist},
volume = {218},
number = {2},
pages = {696-709},
doi = {10.1111/nph.14992},
pmid = {29349810},
issn = {1469-8137},
mesh = {Biological Transport/drug effects ; Cation Transport Proteins/genetics/*metabolism ; Cell Differentiation/drug effects ; Cell Membrane/drug effects/metabolism ; Copper/*metabolism/pharmacology ; Electron Transport Complex IV/metabolism ; Medicago truncatula/cytology/*metabolism ; Multigene Family ; Mutation/genetics ; *Nitrogen Fixation/drug effects ; Nitrogenase/metabolism ; Phenotype ; Plant Proteins/genetics/*metabolism ; Root Nodules, Plant/cytology/drug effects/metabolism ; Saccharomyces cerevisiae/metabolism ; *Symbiosis/drug effects ; },
abstract = {Copper is an essential nutrient for symbiotic nitrogen fixation. This element is delivered by the host plant to the nodule, where membrane copper (Cu) transporter would introduce it into the cell to synthesize cupro-proteins. COPT family members in the model legume Medicago truncatula were identified and their expression determined. Yeast complementation assays, confocal microscopy and phenotypical characterization of a Tnt1 insertional mutant line were carried out in the nodule-specific M. truncatula COPT family member. Medicago truncatula genome encodes eight COPT transporters. MtCOPT1 (Medtr4g019870) is the only nodule-specific COPT gene. It is located in the plasma membrane of the differentiation, interzone and early fixation zones. Loss of MtCOPT1 function results in a Cu-mitigated reduction of biomass production when the plant obtains its nitrogen exclusively from symbiotic nitrogen fixation. Mutation of MtCOPT1 results in diminished nitrogenase activity in nodules, likely an indirect effect from the loss of a Cu-dependent function, such as cytochrome oxidase activity in copt1-1 bacteroids. These data are consistent with a model in which MtCOPT1 transports Cu from the apoplast into nodule cells to provide Cu for essential metabolic processes associated with symbiotic nitrogen fixation.},
}
@article {pmid31530112,
year = {2019},
author = {Caves, EM and Chen, C and Johnsen, S},
title = {The cleaner shrimp Lysmata amboinensis adjusts its behaviour towards predatory versus non-predatory clients.},
journal = {Biology letters},
volume = {15},
number = {9},
pages = {20190534},
doi = {10.1098/rsbl.2019.0534},
pmid = {31530112},
issn = {1744-957X},
abstract = {In cleaning mutualisms, small cleaner organisms remove ectoparasites and dead skin from larger clients. Because cheating by predatory clients can result in cleaner death, cleaners should assess the potential risk of interacting with a given client and adjust their behaviour accordingly. Cleaner shrimp are small marine crustaceans that interact with numerous client fish species, many of which are potential predators. We use in situ observations of cleaner-client interactions to show that the cleaner shrimp Lysmata amboinensis adjusts several behaviours when interacting with predatory versus non-predatory clients. Predatory clients were cleaned in a significantly lower proportion of interactions than non-predatory clients, and cleaners also exhibited a leg rocking behaviour-potentially signalling their identity or intent to clean-almost exclusively toward predatory clients. Incidence of leg rocking was positively correlated with client size, and laboratory experiments showed that it can be elicited by dark visual stimuli and decreases in illumination level. Thus, cleaners clean less frequently when predation risk is higher, and may use leg rocking as a signal advertising cleaning services and directed specifically at predators.},
}
@article {pmid31527788,
year = {2019},
author = {Quigley, KM and Willis, BL and Kenkel, CD},
title = {Transgenerational inheritance of shuffled symbiont communities in the coral Montipora digitata.},
journal = {Scientific reports},
volume = {9},
number = {1},
pages = {13328},
doi = {10.1038/s41598-019-50045-y},
pmid = {31527788},
issn = {2045-2322},
abstract = {Adult organisms may &quot;prime&quot; their offspring for environmental change through a number of genetic and non-genetic mechanisms, termed parental effects. Some coral species may shuffle the proportions of Symbiodiniaceae within their endosymbiotic communities, subsequently altering their thermal tolerance, but it is unclear if shuffled communities are transferred to offspring. We evaluated Symbiodiniaceae community composition in tagged colonies of Montipora digitata over two successive annual spawning seasons and the 2016 bleaching event on the Great Barrier Reef. ITS2 amplicon sequencing was applied to four families (four maternal colonies and 10-12 eggs per family) previously sampled and sequenced the year before to characterize shuffling potential in these M. digitata colonies and determine if shuffled abundances were preserved in gametes. Symbiont densities and photochemical efficiencies differed significantly among adults in 2016, suggesting differential responses to increased temperatures. Low-abundance (&quot;background&quot;) sequence variants differed more among years than between maternal colonies and offspring. Results indicate that shuffling can occur in a canonically 'stable' symbiosis, and that the shuffled community is heritable. Hence, acclimatory changes like shuffling of the Symbiodiniaceae community are not limited to the lifetime of an adult coral and that shuffled communities are inherited across generations in a species with vertical symbiont transmission. Although previously hypothesized, to our knowledge, this is the first evidence that shuffled Symbiodiniaceae communities (at both the inter- and intra- genera level) can be inherited by offspring and supports the hypothesis that shuffling in microbial communities may serve as a mechanism of rapid coral acclimation to changing environmental conditions.},
}
@article {pmid31526475,
year = {2019},
author = {Ericson, CF and Eisenstein, F and Medeiros, JM and Malter, KE and Cavalcanti, GS and Zeller, RW and Newman, DK and Pilhofer, M and Shikuma, NJ},
title = {A contractile injection system stimulates tubeworm metamorphosis by translocating a proteinaceous effector.},
journal = {eLife},
volume = {8},
number = {},
pages = {},
doi = {10.7554/eLife.46845},
pmid = {31526475},
issn = {2050-084X},
support = {1R21DC013180-01A1/DC/NIDCD NIH HHS/United States ; N00014-17-1-2677//Office of Naval Research/ ; N00014-16-1-2135//Office of Naval Research/ ; N00014-14-1-0340//Office of Naval Research/ ; 679209/ERC_/European Research Council/International ; 31003A_179255/SNSF_/Swiss National Science Foundation/Switzerland ; },
abstract = {The swimming larvae of many marine animals identify a location on the sea floor to undergo metamorphosis based on the presence of specific bacteria. Although this microbe-animal interaction is critical for the life cycles of diverse marine animals, what types of biochemical cues from bacteria that induce metamorphosis has been a mystery. Metamorphosis of larvae of the tubeworm Hydroides elegans is induced by arrays of phage tail-like contractile injection systems, which are released by the bacterium Pseudoalteromonas luteoviolacea. Here we identify the novel effector protein Mif1. By cryo-electron tomography imaging and functional assays, we observe Mif1 as cargo inside the tube lumen of the contractile injection system and show that the mif1 gene is required for inducing metamorphosis. Purified Mif1 is sufficient for triggering metamorphosis when electroporated into tubeworm larvae. Our results indicate that the delivery of protein effectors by contractile injection systems may orchestrate microbe-animal interactions in diverse contexts.},
}
@article {pmid31375485,
year = {2019},
author = {Cruz, LF and Menocal, O and Mantilla, J and Ibarra-Juarez, LA and Carrillo, D},
title = {Xyleborus volvulus (Coleoptera: Curculionidae): Biology and Fungal Associates.},
journal = {Applied and environmental microbiology},
volume = {85},
number = {19},
pages = {},
doi = {10.1128/AEM.01190-19},
pmid = {31375485},
issn = {1098-5336},
abstract = {The ambrosia beetle Xyleborus volvulus Fabricius has been reported as a potential vector of the plant pathogen Raffaelea lauricola T.C. Harr., Fraedrich &amp; Aghayeva that is affecting avocado orchards in South Florida. In this study, we examined its life cycle, process of gallery formation, gallery structure, and fungal associates by rearing one generation on avocado sawdust medium under control conditions. The adult foundress excavated a vertical tunnel that constituted the main gallery with a length of 2.5 cm, followed by the construction of up to six secondary galleries with a total length of 4.4 cm. The time period for one generation (egg to adult) was 28 days. Teneral males emerged 3 days after the emergence of the first females. The F1 generation did not significantly contribute to gallery expansion. Four species of Raffaelea and nine yeast species were recovered from galleries and beetles. Raffaelea arxii and Candida berthetii were the most frequent symbionts recovered from new adults and galleries. Candida berthetii dominated during the early stages of the gallery development, whereas R. arxii was most frequent in later stages. Other Raffaelea species were inconsistently isolated from galleries, which suggests a strong association between Xyleborus volvulus and both R. arxii and C. berthetii These results suggest that R. arxii is the primary nutritional symbiont of X. volvulus and that yeast species may be pioneer colonizers that assist with the growth of fungal symbionts.IMPORTANCE Ambrosia beetles cultivate fungi in tunnels bored into weakened host trees. This obligate interaction is required for their survival as beetles feed on these symbiotic fungi, and the fungi benefit from transportation by the beetles. Xyleborus volvulus carries many nonpathogenic symbionts; however, recently the acquisition of Raffaelea lauricola (the causal agent of a lethal vascular disease of lauraceous trees) by this beetle has altered its status from wood degrader to potential pest in avocado. We conducted a study to understand the relationship of this beetle and its fungal associates. Our results show that X. volvulus has a multipartite flexible association with different Raffaelea species. The lack of fidelity in the mutualistic association may explain the acquisition of R. lauricola Knowing the beetle biology and its mutualistic interactions furthers an understanding of the beetle's role as a potential vector and in disease transmission.},
}
@article {pmid30870617,
year = {2019},
author = {Desai, JV and Lionakis, MS},
title = {Setting Up Home: Fungal Rules of Commensalism in the Mammalian Gut.},
journal = {Cell host &amp; microbe},
volume = {25},
number = {3},
pages = {347-349},
doi = {10.1016/j.chom.2019.02.012},
pmid = {30870617},
issn = {1934-6069},
mesh = {Animals ; Candida albicans ; Candidiasis/*microbiology ; Humans ; Mammals ; Symbiosis ; },
abstract = {Candida albicans is a commensal fungus of the human gut, but also causes life-threatening systemic infections. Recent studies published in Cell Host &amp; Microbe (Witchley et al., 2019) and Science (Tso et al., 2018) provide insights into the determinants of C. albicans commensal fitness within the mammalian gut.},
}
@article {pmid30137670,
year = {2018},
author = {Gong, S and Li, Z and Zhang, F and Xiao, Y and Cheng, H},
title = {Symbiochlorum hainanensis gen. et sp. nov. (Ulvophyceae, Chlorophyta) isolated from bleached corals living in the South China Sea.},
journal = {Journal of phycology},
volume = {54},
number = {6},
pages = {811-817},
doi = {10.1111/jpy.12779},
pmid = {30137670},
issn = {1529-8817},
support = {2013CB956103//Major National Scientific Research Project, China/International ; },
mesh = {Animals ; Anthozoa ; China ; Chlorophyta/*classification/cytology/enzymology/genetics ; DNA, Ribosomal Spacer/analysis ; Microalgae/*classification/cytology/enzymology/genetics ; Pacific Ocean ; *Phylogeny ; RNA, Algal/*analysis ; RNA, Ribosomal, 18S/analysis ; Ribulose-Bisphosphate Carboxylase/analysis ; Symbiosis ; },
abstract = {Light/scanning electron/transmission microscopy-based morphological analyses and multiple nucleotide sequences-based molecular phylogenetic analyses are used to identify and assess the phylogenetic position of a new unidentified green alga isolated from bleached corals living in the South China Sea. This new unidentified green alga is a unicellular marine alga and has uninucleate vegetative cells and multiple chloroplasts with a pyrenoid. It can form aplanosporangium covered by cell walls and reproduces by releasing autospore. These features differ substantially from those of the two genera Ignatius and Pseudocharacium. Those two genera have been accommodated in the Ignatius clade. Nucleotide sequences of the nuclear small subunit ribosomal RNA gene (18S rRNA), internal transcribed spacer 2 of ribosomal RNA gene (ITS2) and ribulose-1,5 bisphosphate carboxylase/oxygenase large subunit gene (rbcL, partial) are obtained and compared with published green algal sequences. The results from the morphology, ultrastructure, and multiple nucleotide sequences data support the placement of the new unidentified green alga in Ulvophyceae. This new unidentified isolate is described as Symbiochlorum hainanensis gen. et sp. nov., a new sister lineage to the Ignatius clade, Ulvophyceae, Chlorophyta.},
}
@article {pmid29791719,
year = {2018},
author = {Molins, A and Moya, P and García-Breijo, FJ and Reig-Armiñana, J and Barreno, E},
title = {Molecular and morphological diversity of Trebouxia microalgae in sphaerothallioid Circinaria spp. lichens1.},
journal = {Journal of phycology},
volume = {54},
number = {4},
pages = {494-504},
doi = {10.1111/jpy.12751},
pmid = {29791719},
issn = {1529-8817},
mesh = {Ascomycota/*physiology ; Biodiversity ; Chlorophyta/classification/genetics/*physiology/ultrastructure ; Genetic Variation ; Lichens/classification/genetics/*physiology/ultrastructure ; Microalgae/classification/genetics/*physiology/ultrastructure ; Microscopy, Electron, Transmission ; Phylogeny ; Sequence Analysis, DNA ; Spain ; *Symbiosis ; },
abstract = {Three vagrant (Circinaria hispida, Circinaria gyrosa, and Circinaria sp. 'paramerae') and one crustose (semi-vagrant, Circinaria sp. 'oromediterranea') lichens growing in very continental areas in the Iberian Peninsula were selected to study the phycobiont diversity. Mycobiont identification was checked using nrITS DNA barcoding: Circinaria sp. 'oromediterranea' and Circinaria sp. 'paramerae' formed a new clade. Phycobiont diversity was analyzed in 50 thalli of Circinaria spp. using nrITS DNA and LSU rDNA, with microalgae coexistence being found in all the species analyzed by Sanger sequencing. The survey of phycobiont diversity showed up to four different Trebouxia spp. as the primary phycobiont in 20 thalli of C. hispida, in comparison with the remaining Circinaria spp., where only one Trebouxia was the primary microalga. In lichen species showing coexistence, some complementary approaches are needed (454 pyrosequencing and/or ultrastructural analyses). Five specimens were selected for high-throughput screening (HTS) analyses: 22 Trebouxia OTUs were detected, 10 of them not previously known. TEM analyses showed three different cell morphotypes (Trebouxia sp. OTU A12, OTU S51, and T. cretacea) whose ultrastructure is described here in detail for the first time. HTS revealed a different microalgae pool in each species studied, and we cannot assume a specific pattern between these pools and the ecological and/or morphological characteristics. The mechanisms involved in the selection of the primary phycobiont and the other microalgae by the mycobiont are unknown, and require complex experimental designs. The systematics of the genus Circinaria is not yet well resolved, and more analyses are needed to establish a precise delimitation of the species.},
}
@article {pmid29696650,
year = {2018},
author = {Ziegler, M and Stone, E and Colman, D and Takacs-Vesbach, C and Shepherd, U},
title = {Patterns of Symbiodinium (Dinophyceae) diversity and assemblages among diverse hosts and the coral reef environment of Lizard Island, Australia.},
journal = {Journal of phycology},
volume = {54},
number = {4},
pages = {447-460},
pmid = {29696650},
issn = {1529-8817},
support = {P30 GM110907/GM/NIGMS NIH HHS/United States ; },
mesh = {Animals ; Anthozoa ; *Biodiversity ; Coral Reefs ; DNA, Protozoan/analysis ; DNA, Ribosomal Spacer/analysis ; Dinoflagellida/classification/*genetics/physiology ; *Genetic Variation ; Geologic Sediments/parasitology ; High-Throughput Nucleotide Sequencing ; Queensland ; Symbiosis ; },
abstract = {Large-scale environmental disturbances may impact both partners in coral host-Symbiodinium systems. Elucidation of the assembly patterns in such complex and interdependent communities may enable better prediction of environmental impacts across coral reef ecosystems. In this study, we investigated how the community composition and diversity of dinoflagellate symbionts in the genus Symbiodinium were distributed among 12 host species from six taxonomic orders (Actinaria, Alcyonacea, Miliolida, Porifera, Rhizostoma, Scleractinia) and in the reef water and sediments at Lizard Island, Great Barrier Reef before the 3rd Global Coral Bleaching Event. 454 pyrosequencing of the ITS2 region of Symbiodinium yielded 83 operational taxonomic units (OTUs) at a 97% similarity cut-off. Approximately half of the Symbiodinium OTUs from reef water or sediments were also present in symbio. OTUs belonged to six clades (A-D, F-G), but community structure was uneven. The two most abundant OTUs (100% matches to types C1 and A3) comprised 91% of reads and OTU C1 was shared by all species. However, sequence-based analysis of these dominant OTUs revealed host species specificity, suggesting that genetic similarity cut-offs of Symbiodinium ITS2 data sets need careful evaluation. Of the less abundant OTUs, roughly half occurred at only one site or in one species and the background Symbiodinium communities were distinct between individual samples. We conclude that sampling multiple host taxa with differing life history traits will be critical to fully understand the symbiont diversity of a given system and to predict coral ecosystem responses to environmental change and disturbance considering the differential stress response of the taxa within.},
}
@article {pmid29531241,
year = {2018},
author = {Chen, H and Zhang, Y and Peng, Y and Corlett, RT},
title = {Latitudinal effects on phenology near the northern limit of figs in China.},
journal = {Scientific reports},
volume = {8},
number = {1},
pages = {4320},
pmid = {29531241},
issn = {2045-2322},
mesh = {Animals ; China ; Ficus/*physiology ; *Pollination ; Seasons ; *Symbiosis ; Tropical Climate ; Wasps/*physiology ; },
abstract = {The interaction between pollinating wasps and figs is an obligate plant-insect mutualism, and the ca. 750 Ficus species are mainly tropical. Climatic constraints may limit species distributions through their phenology and this seems particularly likely for figs, where phenological mismatches can cause local extinction of the short-lived pollinators. We therefore compared the phenologies of Ficus altissima, F. racemosa and F. semicordata in tropical Xishuangbanna (21°55'N) and subtropical Liuku (25°50'N), SW China, to understand what factors limit fig distributions near their northern limits. All species produced synchronous crops of syconia in Xishuangbanna but production in Liuku was continuous, which may help maintain pollinator populations. However, in general, we found decreased fitness at the northern site: slower syconium development, so fewer crops each year; fewer seeds per syconium (two species); and fewer pollinators and more non-pollinators per syconium, so less pollen is dispersed. This is most easily explained by colder winters, although low humidities may also contribute, and suggests the northern limit is set by temperature constraints on reproductive phenology. If so, the warming predicted for future decades is expected to enhance the fitness of northern populations of figs and, in the longer term, allow them to shift their range limits northwards.},
}
@article {pmid28721523,
year = {2017},
author = {Messika, I and Garrido, M and Kedem, H and China, V and Gavish, Y and Dong, Q and Fuqua, C and Clay, K and Hawlena, H},
title = {From endosymbionts to host communities: factors determining the reproductive success of arthropod vectors.},
journal = {Oecologia},
volume = {184},
number = {4},
pages = {859-871},
pmid = {28721523},
issn = {1432-1939},
support = {2012063//United States - Israel Binational Science Foundation/International ; FP7-293713//Marie Curie Career Integration Grant/International ; 1391/15//Israel Science Foundation/International ; },
mesh = {Animals ; *Arthropod Vectors ; Female ; *Flea Infestations ; *Reproduction ; Rodentia ; Selection, Genetic ; Siphonaptera ; Symbiosis ; },
abstract = {Elucidating the factors determining reproductive success has challenged scientists since Darwin, but the exact pathways that shape the evolution of life history traits by connecting extrinsic (e.g., landscape structure) and intrinsic (e.g., female's age and endosymbionts) factors and reproductive success have rarely been studied. Here we collected female fleas from wild rodents in plots differing in their densities and proportions of the most dominant rodent species. We then combined path analysis and model selection approaches to explore the network of effects, ranging from micro to macroscales, determining the reproductive success of these fleas. Our results suggest that female reproductive success is directly and positively associated with their infection by Mycoplasma bacteria and their own body mass, and with the rodent species size and total density. In addition, we found evidence for indirect effects of rodent sex and rodent community diversity on female reproductive success. These results highlight the importance of exploring interrelated factors across organization scales while studying the reproductive success of wild organisms, and they have implications for the control of vector-borne diseases.},
}
@article {pmid28707111,
year = {2017},
author = {Furukawa, S and Kawakita, A},
title = {Limiting the cost of mutualism: the defensive role of elongated gynophore in the leafflower-moth mutualism.},
journal = {Oecologia},
volume = {184},
number = {4},
pages = {835-846},
pmid = {28707111},
issn = {1432-1939},
support = {24770018//Japan Society for the Promotion of Science/International ; },
mesh = {Animals ; Female ; *Flowers ; Fruit ; Geography ; Larva ; *Moths ; *Oviposition ; Parasites ; Pollination ; Seeds ; *Symbiosis ; },
abstract = {Mutualisms are interactions from which both partners benefit but may collapse if mutualists' costs and benefits are not aligned. Host sanctions are one mechanism whereby hosts selectively allocate resources to the more cooperative partners and thereby reduce the fitness of overexploiters; however, many mutualisms lack apparent means of host sanctions. In mutualisms between plants and pollinating seed parasites, such as those between leafflowers and leafflower moths, pollinators consume subsets of the seeds as larval food in return for their pollination service. Plants may select against overexploiters by selectively aborting flowers with a heavy egg load, but in many leafflower species, seeds are fully eaten in some fruits, suggesting that such a mechanism is not present in all species. Instead, the fruits of Breynia vitis-idaea have stalk-like structures (gynophore) through which early-instar moth larvae must bore to reach seeds. Examination of moth mortality in fruits with different gynophore lengths suggested that fruits with longer gynophore had higher moth mortality and, therefore, less seed damage. Most moth mortality occurred at the egg stage or as early larval instar before moths reached the seeds, consistent with the view that gynophore functions to prevent moth access to seeds. Gynophore length was unaffected by plant size, extent of moth oviposition, or geography; thus, it is most likely genetically controlled. Because gynophores do not elongate in related species whose pollinators oviposit directly into the ovary, the gynophore in B. vitis-idaea may have evolved as a defense to limit the cost of the mutualism.},
}
@article {pmid31523509,
year = {2019},
author = {Yeoman, CJ and Brutscher, LM and Esen, ÖC and Ibaoglu, F and Fowler, C and Eren, AM and Wanner, K and Weaver, DK},
title = {Genome-resolved insights into a novel Spiroplasma symbiont of the Wheat Stem Sawfly (Cephus cinctus).},
journal = {PeerJ},
volume = {7},
number = {},
pages = {e7548},
doi = {10.7717/peerj.7548},
pmid = {31523509},
issn = {2167-8359},
abstract = {Arthropods often have obligate relationships with symbiotic microbes, and recent investigations have demonstrated that such host-microbe relationships could be exploited to suppress natural populations of vector carrying mosquitos. Strategies that target the interplay between agricultural pests and their symbionts could decrease the burden caused by agricultural pests; however, the lack of comprehensive genomic insights into naturally occurring microbial symbionts presents a significant bottleneck. Here we employed amplicon surveys, genome-resolved metagenomics, and scanning electron microscopy to investigate symbionts of the wheat stem sawfly (Cephus cinctus), a major pest that causes an estimated $350 million dollars or more in wheat yield losses in the northwestern United States annually. Through 16S rRNA gene sequencing of two major haplotypes and life stages of wheat stem sawfly, we show a novel Spiroplasma species is ever-present and predominant, with phylogenomic analyses placing it as a member of the ixodetis clade of mollicutes. Using state-of-the-art metagenomic assembly and binning strategies we were able to reconstruct a 714 Kb, 72.7%-complete Spiroplasma genome, which represents just the second draft genome from the ixodetis clade of mollicutes. Functional annotation of the Spiroplasma genome indicated carbohydrate-metabolism involved PTS-mediated import of glucose and fructose followed by glycolysis to lactate, acetate, and propionoate. The bacterium also encoded biosynthetic pathways for essential vitamins B2, B3, and B9. We identified putative Spiroplasma virulence genes: cardiolipin and chitinase. These results identify a previously undescribed symbiosis between wheat stem sawfly and a novel Spiroplasma sp., availing insight into their molecular relationship, and may yield new opportunities for microbially-mediated pest control strategies.},
}
@article {pmid31522775,
year = {2019},
author = {Requena, T and Velasco, M},
title = {The human microbiome in sickness and in health.},
journal = {Revista clinica espanola},
volume = {},
number = {},
pages = {},
doi = {10.1016/j.rce.2019.07.004},
pmid = {31522775},
issn = {1578-1860},
abstract = {The study of the human microbiome has led to an exceptional increase in the current understanding of the importance of microbiota for health throughout all stages of life. Human microbial colonization occurs in the skin, genitourinary system and, mainly, in the oral cavity and intestinal tract. In these locations, the human microbiota establishes a symbiotic relationship with the host and helps maintain the physiological homeostasis. Lifestyle, age, diet and use of antibiotics are the main regulators of the composition and functionality of human microbiota. Recent studies have indicated the reduction in microbial diversity as one of the contributors to the development of diseases. In addition to phylogenetic diversity studies, further metagenomic studies are needed at the functional level of the human microbiome to improve our understanding of its involvement in human health.},
}
@article {pmid30787435,
year = {2019},
author = {Whiteley, AT and Eaglesham, JB and de Oliveira Mann, CC and Morehouse, BR and Lowey, B and Nieminen, EA and Danilchanka, O and King, DS and Lee, ASY and Mekalanos, JJ and Kranzusch, PJ},
title = {Bacterial cGAS-like enzymes synthesize diverse nucleotide signals.},
journal = {Nature},
volume = {567},
number = {7747},
pages = {194-199},
doi = {10.1038/s41586-019-0953-5},
pmid = {30787435},
issn = {1476-4687},
support = {S10 RR029205/RR/NCRR NIH HHS/United States ; R01 AI026289/AI/NIAID NIH HHS/United States ; R01 AI018045/AI/NIAID NIH HHS/United States ; S10 OD021527/OD/NIH HHS/United States ; S10 OD021832/OD/NIH HHS/United States ; P30 GM124165/GM/NIGMS NIH HHS/United States ; T32 CA207021/CA/NCI NIH HHS/United States ; },
mesh = {Animals ; Bacterial Proteins/*metabolism ; Crystallography, X-Ray ; Dinucleoside Phosphates/biosynthesis/metabolism ; HEK293 Cells ; Humans ; Mice ; Nucleotides/*biosynthesis/chemistry/*metabolism ; Nucleotidyltransferases/*chemistry/genetics/*metabolism ; Operon/genetics ; Symbiosis ; },
abstract = {Cyclic dinucleotides (CDNs) have central roles in bacterial homeostasis and virulence by acting as nucleotide second messengers. Bacterial CDNs also elicit immune responses during infection when they are detected by pattern-recognition receptors in animal cells. Here we perform a systematic biochemical screen for bacterial signalling nucleotides and discover a large family of cGAS/DncV-like nucleotidyltransferases (CD-NTases) that use both purine and pyrimidine nucleotides to synthesize a diverse range of CDNs. A series of crystal structures establish CD-NTases as a structurally conserved family and reveal key contacts in the enzyme active-site lid that direct purine or pyrimidine selection. CD-NTase products are not restricted to CDNs and also include an unexpected class of cyclic trinucleotide compounds. Biochemical and cellular analyses of CD-NTase signalling nucleotides demonstrate that these cyclic di- and trinucleotides activate distinct host receptors and thus may modulate the interaction of both pathogens and commensal microbiota with their animal and plant hosts.},
}
@article {pmid29963630,
year = {2018},
author = {Kitada, Y and Muramatsu, K and Toju, H and Kibe, R and Benno, Y and Kurihara, S and Matsumoto, M},
title = {Bioactive polyamine production by a novel hybrid system comprising multiple indigenous gut bacterial strategies.},
journal = {Science advances},
volume = {4},
number = {6},
pages = {eaat0062},
pmid = {29963630},
issn = {2375-2548},
mesh = {Agmatine/metabolism ; Animals ; Bacteria/metabolism ; Biosynthetic Pathways ; Escherichia coli/metabolism ; Feces/microbiology ; *Gastrointestinal Microbiome ; Humans ; Mice ; Polyamines/*metabolism ; Putrescine/biosynthesis ; Symbiosis ; Transcriptome ; },
abstract = {Metabolites of the intestinal microbiota are thought to be generated through metabolic pathways spanning multiple taxa of intestinal bacteria. We have previously shown that the level of putrescine, a polyamine found abundantly in the human intestinal lumen, is increased in the colonic lumen following administration of arginine and the probiotic Bifidobacterium sp.; however, the underlying mechanism remained poorly understood. We report a novel pathway for putrescine production from arginine through agmatine involving the collaboration of two bacterial groups, and triggered by environmental acidification (drop in pH to below 6.5 from neutral). This pathway comprises the acid tolerance system of Escherichia coli, representing bacteria that have an arginine-dependent acid resistance system; the energy production system of Enterococcus faecalis, representing bacteria that have an agmatine deiminase system; and the acid production system of the acid-producing bacteria, represented by Bifidobacterium spp. This pathway is unique in that it represents a relationship between the independent survival strategies of multiple bacteria.},
}
@article {pmid29476118,
year = {2018},
author = {Stuhr, M and Blank-Landeshammer, B and Reymond, CE and Kollipara, L and Sickmann, A and Kucera, M and Westphal, H},
title = {Disentangling thermal stress responses in a reef-calcifier and its photosymbionts by shotgun proteomics.},
journal = {Scientific reports},
volume = {8},
number = {1},
pages = {3524},
pmid = {29476118},
issn = {2045-2322},
mesh = {Aquatic Organisms ; Calcification, Physiologic/genetics ; Coral Reefs ; Diatoms/*genetics/growth &amp; development/metabolism ; Ecosystem ; Foraminifera/*genetics/growth &amp; development/metabolism ; Gene Expression Regulation ; Gene Ontology ; Hot Temperature ; Molecular Sequence Annotation ; Oceans and Seas ; Photosynthesis/genetics ; Proteome/classification/*genetics/metabolism ; Proteomics/*methods ; *Stress, Physiological ; Symbiosis ; },
abstract = {The proliferation of key marine ecological engineers and carbonate producers often relies on their association with photosymbiotic algae. Evaluating stress responses of these organisms is important to predict their fate under future climate projections. Physiological approaches are limited in their ability to resolve the involved molecular mechanisms and attribute stress effects to the host or symbiont, while probing and partitioning of proteins cannot be applied in organisms where the host and symbiont are small and cannot be physically separated. Here we apply a label-free quantitative proteomics approach to detect changes of proteome composition in the diatom-bearing benthic foraminifera Amphistegina gibbosa experimentally exposed to three thermal-stress scenarios. We developed a workflow for protein extraction from less than ten specimens and simultaneously analysed host and symbiont proteomes. Despite little genomic data for the host, 1,618 proteins could be partially assembled and assigned. The proteomes revealed identical pattern of stress response among stress scenarios as that indicated by physiological measurements, but allowed identification of compartment-specific stress reactions. In the symbiont, stress-response and proteolysis-related proteins were up regulated while photosynthesis-related proteins declined. In contrast, host homeostasis was maintained through chaperone up-regulation associated with elevated proteosynthesis and proteolysis, and the host metabolism shifted to heterotrophy.},
}
@article {pmid31521732,
year = {2019},
author = {Horiuchi, A and Kokubu, E and Warita, T and Ishihara, K},
title = {Synergistic biofilm formation by Parvimonas micra and Fusobacterium nucleatum.},
journal = {Anaerobe},
volume = {},
number = {},
pages = {102100},
doi = {10.1016/j.anaerobe.2019.102100},
pmid = {31521732},
issn = {1095-8274},
abstract = {Parvimonas micra is frequently isolated from lesions of apical periodontitis and is a major disease-related pathogen. One of the main causes of apical periodontitis is extraradicular biofilm. In this study, we investigated polymicrobial biofilm formation by P. micra and species associated with apical periodontitis. The coaggregation activity of P. micra with partner strains was investigated by visual assays. Synergistic biofilm formation was evaluated by cocultures of P. micra and partner strains. Growth of planktonic cells was measured by evaluating the absorbance at OD660, and biofilm formation was examined by staining with crystal violet. The effects of soluble components on synergistic biofilm formation and planktonic cell growth were examined after coculture of P. micra and other strains separated with a 0.4-μm pore-size porous membrane. P. micra coaggregated with Fusobacterium nucleatum, Porphyromonas gingivalis, or Capnoctyophaga ochracea. P. micra showed no coaggregation with Staphylococcus aureus, S. epidermidis, or Prevotella intermedia. In mixed cultures, biofilm formation by P. micra and F. nucleatum was greater than that by P. micra and P. gingivalis or C. ochracea. In separated cocultures, planktonic cell growth of P. micra was enhanced by each of the three species. Biofilm formation by P. micra was enhanced by F. nucleatum and C. ochracea; however, no significant enhancement was observed with P. gingivalis. These data indicated that P. micra and F. nucleatum had synergistic effects in biofilm formation and that these effects may be important for colonization by these two species in apical periodontitis lesions.},
}
@article {pmid31521050,
year = {2019},
author = {Farci, D and Sanna, C and Medda, R and Pintus, F and Kalaji, HM and Kirkpatrick, J and Piano, D},
title = {Shedding light on the presymbiontic phase of C. arietinum.},
journal = {Plant physiology and biochemistry : PPB},
volume = {143},
number = {},
pages = {224-231},
doi = {10.1016/j.plaphy.2019.09.014},
pmid = {31521050},
issn = {1873-2690},
abstract = {A complex network of symbiotic events between plants and bacteria allows the biosphere to exploit the atmospheric reservoir of molecular nitrogen. In seeds, a series of presymbiotic steps are already identified during imbibition, while interactions between the host and its symbiont begin in the early stages of germination. In the present study, a detailed analysis of the substances' complex delivered by Cicer arietinum seeds during imbibition showed a relevant presence of proteins and amino acids, which, except for cysteine, occurred with the whole proteinogenic pool. The imbibing solution was found to provide essential probiotic properties able to sustain the growth of the specific chickpea symbiont Mesorhizobium ciceri. Moreover, the imbibing solution, behaving as a complete medium, was found to be critically important for the symbiont's attraction, a fact this that is strictly related to the presence of the amino acids glycine, serine, and threonine. Here, the presence of these amino acids is constantly supported by the presence of the enzymes serine hydroxymethyltransferase and formyltetrahydrofolate deformylase, which are both involved in their biosynthesis. The reported findings are discussed in the light of the pivotal role played by the imbibing solution in attracting and sustaining symbiosis between the host and its symbiont.},
}
@article {pmid31521032,
year = {2019},
author = {Genc, O and van Capelleveen, G and Erdis, E and Yildiz, O and Yazan, DM},
title = {A socio-ecological approach to improve industrial zones towards eco-industrial parks.},
journal = {Journal of environmental management},
volume = {250},
number = {},
pages = {109507},
doi = {10.1016/j.jenvman.2019.109507},
pmid = {31521032},
issn = {1095-8630},
abstract = {One of the concrete examples of industrial symbiosis development is eco-industrial parks, which improves resource efficiency and minimizes environmental impacts by adopting models for waste exchanges between industries. Despite past efforts, many industrial zones around the world are not yet considered as eco-industrial parks because of the low number (or total lack) of symbiotic relationships among industries. A promising strategy is to develop those existing industrial zones into eco-industrial parks. However, there is a lack of studies addressing how to assess environmental improvement in relation to network sustainability. This study demonstrates such an assessment approach using an integration of food web analysis and social network analysis. These two methods can assist in assessing differences in network configurations with respect to potential implementations of industrial symbiosis, and in analysing the resilience, redundancy, connectance, and cyclicity of eco-parks. The use of the methods is illustrated in a case study of an industrial zone in Turkey. Four potential future scenarios are proposed, including potential future co-location of companies in the industrial zone in order to foster industrial symbiotic network formation. These scenarios are compared with the current configuration. The results indicate the method's ability to assess the resilience of an industrial network. Moreover, the case shows an improvement of network sustainability and follows some sustainable properties of natural ecosystems as a result of implementing the industrial symbiosis.},
}
@article {pmid31520944,
year = {2019},
author = {Noman, A and Aqeel, M and Qasim, M and Haider, I and Lou, Y},
title = {Plant-insect-microbe interaction: A love triangle between enemies in ecosystem.},
journal = {The Science of the total environment},
volume = {699},
number = {},
pages = {134181},
doi = {10.1016/j.scitotenv.2019.134181},
pmid = {31520944},
issn = {1879-1026},
abstract = {In natural ecosystems, plants interact with biotic components such as microbes, insects, animals and other plants as well. Generally, researchers have focused on each interaction separately, which condenses the significance of the interaction. This limited presentation of the facts masks the collective role of constantly interacting organisms in complex communities disturbing not only plant responses but also the response of organisms for each other in natural ecological settings. Beneficial microorganisms interact with insect herbivores, their predators and pollinators in a bidirectional way through the plant. Fascinatingly, insects employ diverse tactics to protect themselves from parasites or predators. Influences of microbial and insects attack on plants can bring changes in info-chemical frameworks and play a role in the food chain also. After insect herbivory and microbial pathogenesis, plants exhibit intense morpho-physiological and chemical reprogramming that leads to repellence/attraction of attacking organism or its natural enemy. The characterization of such interactions in different ecosystems is receiving due consideration, and underlying molecular and physiological mechanisms must be the point of concentration to unveil the evolution of multifaceted multitrophic interactions. Therefore, we have focused this phenomenon in a more realistic setting by integrating ecology and physiology to portray these multidimensional interfaces. We have shown, in this article, physiological trajectories in plant-microbe and insect relationship and their ecological relevance in nature. We focus and discuss microbial pathogenesis in plants, induced defense and the corresponding behavior of herbivore insects and vice-versa. It is hoped that this review will stimulate interest and zeal in microbes mediated plant-insect interactions along with their ecological consequences and encourage scientists to accept the challenges in this field.},
}
@article {pmid31518652,
year = {2019},
author = {Carrillo, JD and Rugman-Jones, PF and Husein, D and Stajich, JE and Kasson, MT and Carrillo, D and Stouthamer, R and Eskalen, A},
title = {Members of the Euwallacea fornicatus species complex exhibit promiscuous mutualism with ambrosia fungi in Taiwan.},
journal = {Fungal genetics and biology : FG &amp; B},
volume = {},
number = {},
pages = {103269},
doi = {10.1016/j.fgb.2019.103269},
pmid = {31518652},
issn = {1096-0937},
abstract = {Carrillo, J.D., Rugman-Jones, PF., Husein, D., Stajich, J.E., Kasson, MT., Carrillo, D., Stouthamer, R., and Eskalen, A. 2019. Members of the Euwallacea fornicatus species complex exhibit promiscuous mutualism with ambrosia fungi in Taiwan A number of ambrosia beetles have come to prominence in recent years because of the damage they inflict on a variety of trees within invaded habitats across the globe. Ambrosia beetles rely on symbiotic microorganisms, mainly fungi, as a dedicated food source and carry those microorganisms around with them within specialized organs termed mycangia. Investigation of members of the Euwallacea fornicatus species complex and their fungal symbionts in Taiwan revealed promiscuous symbioses with ambrosial Fusaria clade (AFC) members, Graphium spp., and Paracremonium spp. based on co-phylogenetic analyses. For AFC members, a novel diagnostic PCR assay targeting mating type genes MAT1-1-1 and MAT1-2-1 was developed and validated by amplicon size and sequencing. Mating types screening of AFC members revealed the isolates screened are all heterothallic (self-sterile), with both MAT types represented and recovered from fungi vectored by E. fornicatus, E. kuroshio, and E. whitfordiodendrus in Taiwan. Members of the Euwallacea fornicatus species complex and the variety of ambrosia fungi they utilize further confirms that their relationship with fungi are more likely promiscuous in native areas, as opposed to strictly obligate to a specific combination of fungi as observed in invaded areas.},
}
@article {pmid31515637,
year = {2019},
author = {Liu, B and Liu, X and Liu, F and Ma, H and Ma, B and Zhang, W and Peng, L},
title = {Growth improvement of Lolium multiflorum Lam. induced by seed inoculation with fungus suspension of Xerocomus badius and Serendipita indica.},
journal = {AMB Express},
volume = {9},
number = {1},
pages = {145},
doi = {10.1186/s13568-019-0865-7},
pmid = {31515637},
issn = {2191-0855},
support = {2019LY009//Forestry Science and Technology Innovation Project of Shandong Province/ ; 31570614//National Natural Science Foundation of China/ ; },
abstract = {In this study, a pot experiment was carried out in greenhouse to investigate the potentials of Xerocomus badius and Serendipita indica to penetrate and colonize roots of ryegrass (Lolium multiflorum Lam.) and to induce beneficial effects on seed germination and seedling growth. The results showed that X. badius and S. indica successfully colonized in the root system of L. multiflorum seedlings and the root colonization rate was 72.65% and 88.42%, respectively. By microscopy, the hyphae, chlamydospores and spores produced by S. indica were observed in roots cortex of L. multiflorum seedlings. In comparison with the non-inoculated seedlings, seedlings inoculated with X. badius and S. indica showed significant increase in growth parameters with plant height, basal diameter, biomass accumulation, relative growth rate, leaf relative water content and chlorophyll content. Also, we found that seedlings inoculated with S. indica exhibited a greater growth-promotion as compared with X. badius-inoculated seedlings. No significant influence of the two fungus application has been observed with respect to seed germination. It suggested that well establishments of mutualistic symbiosis between L. multiflorum and X. badius or S. indica were not so essential to seed germination but contributed highly to the survival and growth of the seedlings.},
}
@article {pmid30936488,
year = {2019},
author = {Spang, A and Stairs, CW and Dombrowski, N and Eme, L and Lombard, J and Caceres, EF and Greening, C and Baker, BJ and Ettema, TJG},
title = {Proposal of the reverse flow model for the origin of the eukaryotic cell based on comparative analyses of Asgard archaeal metabolism.},
journal = {Nature microbiology},
volume = {4},
number = {7},
pages = {1138-1148},
doi = {10.1038/s41564-019-0406-9},
pmid = {30936488},
issn = {2058-5276},
mesh = {Archaea/classification/*genetics/*metabolism ; Archaeal Proteins/genetics ; *Biological Evolution ; Eukaryotic Cells/metabolism/*physiology ; Genome, Archaeal/genetics ; Heterotrophic Processes ; Hydrogen/metabolism ; Metabolic Networks and Pathways ; *Models, Biological ; Oxidation-Reduction ; *Phylogeny ; Symbiosis ; },
abstract = {The origin of eukaryotes represents an unresolved puzzle in evolutionary biology. Current research suggests that eukaryotes evolved from a merger between a host of archaeal descent and an alphaproteobacterial endosymbiont. The discovery of the Asgard archaea, a proposed archaeal superphylum that includes Lokiarchaeota, Thorarchaeota, Odinarchaeota and Heimdallarchaeota suggested to comprise the closest archaeal relatives of eukaryotes, has helped to elucidate the identity of the putative archaeal host. Whereas Lokiarchaeota are assumed to employ a hydrogen-dependent metabolism, little is known about the metabolic potential of other members of the Asgard superphylum. We infer the central metabolic pathways of Asgard archaea using comparative genomics and phylogenetics to be able to refine current models for the origin of eukaryotes. Our analyses indicate that Thorarchaeota and Lokiarchaeota encode proteins necessary for carbon fixation via the Wood-Ljungdahl pathway and for obtaining reducing equivalents from organic substrates. By contrast, Heimdallarchaeum LC2 and LC3 genomes encode enzymes potentially enabling the oxidation of organic substrates using nitrate or oxygen as electron acceptors. The gene repertoire of Heimdallarchaeum AB125 and Odinarchaeum indicates that these organisms can ferment organic substrates and conserve energy by coupling ferredoxin reoxidation to respiratory proton reduction. Altogether, our genome analyses suggest that Asgard representatives are primarily organoheterotrophs with variable capacity for hydrogen consumption and production. On this basis, we propose the 'reverse flow model', an updated symbiogenetic model for the origin of eukaryotes that involves electron or hydrogen flow from an organoheterotrophic archaeal host to a bacterial symbiont.},
}
@article {pmid30332582,
year = {2018},
author = {Winbourne, JB and Harrison, MT and Sullivan, BW and Alvarez-Clare, S and Lins, SR and Martinelli, L and Nasto, M and Piotto, D and Rolim, S and Wong, M and Porder, S},
title = {A New Framework for Evaluating Estimates of Symbiotic Nitrogen Fixation in Forests.},
journal = {The American naturalist},
volume = {192},
number = {5},
pages = {618-629},
doi = {10.1086/699828},
pmid = {30332582},
issn = {1537-5323},
mesh = {Bacteria ; Brazil ; Computer Simulation ; Costa Rica ; *Nitrogen Fixation ; *Rainforest ; Root Nodules, Plant/*metabolism ; Soil/chemistry ; Symbiosis/physiology ; Tropical Climate ; },
abstract = {Symbiotic nitrogen fixation (SNF) makes atmospheric nitrogen biologically available and regulates carbon storage in many terrestrial ecosystems. Despite its global importance, estimates of SNF rates are highly uncertain, particularly in tropical forests where rates are assumed to be high. Here we provide a framework for evaluating the uncertainty of sample-based SNF estimates and discuss its implications for quantifying SNF and thus understanding of forest function. We apply this framework to field data sets from six lowland tropical rainforests (mature and secondary) in Brazil and Costa Rica. We use this data set to estimate parameters influencing SNF estimation error, notably the root nodule abundance and variation in SNF rates among soil cores containing root nodules. We then use simulations to gauge the relationship between sampling effort and SNF estimation accuracy for a combination of parameters. Field data illuminate a highly right-skewed lognormal distribution of SNF rates among soil cores containing root nodules that were rare and spanned five orders of magnitude. Consequently, simulations demonstrated that sample sizes of hundreds to even thousands of soil cores are needed to obtain estimates of SNF that are within, for example, a factor of 2 of the actual rate with 75% probability. This represents sample sizes that are larger than most studies to date. As a result of this previously undescribed uncertainty, we suggest that current estimates of SNF in tropical forests are not sufficiently constrained to elucidate forest stand-level controls of SNF, which hinders our understanding of the impact of SNF on tropical forest ecosystem processes.},
}
@article {pmid30109687,
year = {2019},
author = {Pierart, A and Maes, AQ and Dumat, C and Sejalon-Delmas, N},
title = {Vermicompost addition influences symbiotic fungi communities associated with leek cultivated in metal-rich soils.},
journal = {Environmental science and pollution research international},
volume = {26},
number = {20},
pages = {20040-20051},
doi = {10.1007/s11356-018-2803-7},
pmid = {30109687},
issn = {1614-7499},
support = {ANR-12-0011-VBDU//Agence Nationale de la Recherche/ ; },
mesh = {Agriculture/methods ; *Composting ; Metals/*pharmacokinetics ; Mycobiome/genetics/*physiology ; Mycorrhizae ; Onions/*growth &amp; development/microbiology ; Plant Roots/*microbiology ; Soil/chemistry ; Soil Microbiology ; Soil Pollutants/*pharmacokinetics ; Symbiosis ; },
abstract = {In the context of urban agriculture, where soils are frequently contaminated with metal(loid)s (TM), we studied the influence of vermicompost amendments on symbiotic fungal communities associated with plants grown in two metal-rich soils. Leek (Allium porrum L.) plants were grown with or without vermicompost in two metal-rich soils characterized by either geogenic or anthropogenic TM sources, to assess the influence of pollutant origin on soil-plant transfer. Fungal communities associated with the leek roots were identified by high throughput Illumina MiSeq and TM contents were measured using mass spectrometry. Vermicompost addition led to a dramatic change in the fungal community with a loss of diversity in the two tested soils. This effect could partially explain the changes in metal transfer at the soil-AMF-plant interface. Our results suggest being careful while using composts when growing edibles in contaminated soils. More generally, this study highlights the need for further research in the field of fungal communities to refine practical recommendations to gardeners. Graphical abstract.},
}
@article {pmid29732407,
year = {2018},
author = {Blažek, R and Polačik, M and Smith, C and Honza, M and Meyer, A and Reichard, M},
title = {Success of cuckoo catfish brood parasitism reflects coevolutionary history and individual experience of their cichlid hosts.},
journal = {Science advances},
volume = {4},
number = {5},
pages = {eaar4380},
pmid = {29732407},
issn = {2375-2548},
mesh = {Animals ; *Biological Evolution ; Catfishes/*physiology ; Cichlids/*physiology ; Reproduction ; Species Specificity ; *Symbiosis ; },
abstract = {Obligate brood parasites manipulate other species into raising their offspring. Avian and insect brood parasitic systems demonstrate how interacting species engage in reciprocal coevolutionary arms races through behavioral and morphological adaptations and counteradaptations. Mouthbrooding cichlid fishes are renowned for their remarkable evolutionary radiations and complex behaviors. In Lake Tanganyika, mouthbrooding cichlids are exploited by the only obligate nonavian vertebrate brood parasite, the cuckoo catfish Synodontis multipunctatus. We show that coevolutionary history and individual learning both have a major impact on the success of cuckoo catfish parasitism between coevolved sympatric and evolutionarily naïve allopatric cichlid species. The rate of cuckoo catfish parasitism in coevolved Tanganyikan hosts was 3 to 11 times lower than in evolutionarily naïve cichlids. Moreover, using experimental infections, we demonstrate that parasite egg rejection in sympatric hosts was much higher, leading to seven times greater parasite survival in evolutionarily naïve than sympatric hosts. However, a high rejection frequency of parasitic catfish eggs by coevolved sympatric hosts came at a cost of increased rejection of their own eggs. A significant cost of catfish parasitism was universal, except for coevolved sympatric cichlid species with previous experience of catfish parasitism, demonstrating that learning and individual experience both contribute to a successful host response.},
}
@article {pmid29462403,
year = {2018},
author = {Lebreton, F and Valentino, MD and Schaufler, K and Earl, AM and Cattoir, V and Gilmore, MS},
title = {Transferable vancomycin resistance in clade B commensal-type Enterococcus faecium.},
journal = {The Journal of antimicrobial chemotherapy},
volume = {73},
number = {6},
pages = {1479-1486},
pmid = {29462403},
issn = {1460-2091},
support = {HHSN272200900018C/AI/NIAID NIH HHS/United States ; P01 AI083214/AI/NIAID NIH HHS/United States ; R01 AI072360/AI/NIAID NIH HHS/United States ; U19 AI110818/AI/NIAID NIH HHS/United States ; },
mesh = {Anti-Bacterial Agents/pharmacology ; Bacterial Proteins/genetics ; Cross Infection/microbiology ; Enterococcus faecium/drug effects/*genetics ; Feces/microbiology ; Genome, Bacterial ; Gram-Positive Bacterial Infections/microbiology ; Humans ; Immunocompromised Host ; Microbial Sensitivity Tests ; Operon ; Phylogeny ; Plasmids/*genetics ; Symbiosis ; Vancomycin/pharmacology ; Vancomycin Resistance/*genetics ; Vancomycin-Resistant Enterococci/*genetics ; },
abstract = {Objectives: Vancomycin-resistant Enterococcus faecium is a leading cause of MDR hospital infection. Two genetically definable populations of E. faecium have been identified: hospital-adapted MDR isolates (clade A) and vancomycin-susceptible commensal strains (clade B). VanN-type vancomycin resistance was identified in two isolates of E. faecium recovered from blood and faeces of an immunocompromised patient. To understand the genomic context in which VanN occurred in the hospitalized patient, the risk it posed for transmission in the hospital and its origins, it was of interest to determine where these strains placed within the E. faecium population structure.<br><br>Methods: We obtained the genome sequence of the VanN isolates and performed comparative and functional genomics of the chromosome and plasmid content.<br><br>Results: We show that, in these strains, VanN occurs in a genetic background that clusters with clade B E. faecium, which is highly unusual. We characterized the chromosome and the conjugative plasmid that carries VanN resistance in these strains, pUV24. This plasmid exhibits signatures of in-host selection on the vanN operon regulatory system, which are associated with a constitutive expression of vancomycin resistance. VanN resistance in clade B strains may go undetected by current methods.<br><br>Conclusions: We report a case of vancomycin resistance in a commensal lineage of E. faecium responsible for an atypical bacteraemia in an immunocompromised patient. A reservoir of transferable glycopeptide resistance in the community could pose a concern for public health.},
}
@article {pmid29385453,
year = {2018},
author = {Wang, Y and Staubach, F},
title = {Individual variation of natural D.melanogaster-associated bacterial communities.},
journal = {FEMS microbiology letters},
volume = {365},
number = {6},
pages = {},
doi = {10.1093/femsle/fny017},
pmid = {29385453},
issn = {1574-6968},
mesh = {Animals ; Bacteria/classification/genetics ; Biodiversity ; Drosophila melanogaster/*microbiology ; Male ; Metagenome ; Metagenomics/methods ; *Microbiota ; RNA, Ribosomal, 16S ; Symbiosis ; },
abstract = {Drosophila melanogaster has become an important model organism to study host-microbe interaction in the laboratory. However, the natural microbial communities that are associated with D. melanogaster have received less attention. Especially, information on inter-individual variation is still lacking, because most studies so far have used pooled material from several flies. Here, we collected bacterial 16S rRNA gene community profiles from a set of 32 individuals from a single population. We simulated pools from the individual data (i) to assess how well the microbiome of a host population is represented by pools, and (ii) to compare variation of Drosophila microbiomes within and between populations. Taxon richness was increased in simulated pools, suggesting that pools paint a more comprehensive picture of the taxa associated with a host population. Furthermore, microbiome composition varied less between pools than between individuals, indicating that differences even out in pools. Variation in microbiome composition was larger between populations than between simulated pools from a single population, adding to the notion that there are population-specific effects on the Drosophila microbiome. Surprisingly, samples from individuals clustered into two groups, suggesting that there are yet unknown factors that affect the composition of natural fly-associated microbial communities and need further research.},
}
@article {pmid29292829,
year = {2018},
author = {Raven, JA and Lambers, H and Smith, SE and Westoby, M},
title = {Costs of acquiring phosphorus by vascular land plants: patterns and implications for plant coexistence.},
journal = {The New phytologist},
volume = {217},
number = {4},
pages = {1420-1427},
doi = {10.1111/nph.14967},
pmid = {29292829},
issn = {1469-8137},
mesh = {Adaptation, Physiological ; Embryophyta/*metabolism ; Phosphorus/*metabolism ; Plant Roots/physiology ; Soil/chemistry ; *Symbiosis ; },
abstract = {Content Summary 1420 I. Introduction 1421 II. Root adaptations that influence P acquisition 1422 III. Costs of P acquisition: general 1423 IV. Costs of P acquisition that are independent of soil P concentrations 1423 V. Costs of P acquisition that increase as soil P concentrations decline 1424 VI. Discussion and conclusions 1424 Acknowledgements 1425 References 1425 SUMMARY: We compare carbon (and hence energy) costs of the different modes of phosphorus (P) acquisition by vascular land plants. Phosphorus-acquisition modes are considered to be mechanisms of plants together with their root symbionts and structures such as cluster roots involved in mobilising or absorbing P. Phosphorus sources considered are soluble and insoluble inorganic and organic pools. Costs include operating the P-acquisition mechanisms, and resource requirements to construct and maintain them. For most modes, costs increase as the relevant soil P concentration declines. Costs can thus be divided into a component incurred irrespective of soil P concentration, and a component describing how quickly costs increase as the soil P concentration declines. Differences in sensitivity of costs to soil P concentration arise mainly from how economically mycorrhizal fungal hyphae or roots that explore the soil volume are constructed, and from costs of exudates that hydrolyse or mobilise insoluble P forms. In general, modes of acquisition requiring least carbon at high soil P concentrations experience a steeper increase in costs as soil P concentrations decline. The relationships between costs and concentrations suggest some reasons why different modes coexist, and why the mixture of acquisition modes differs between sites.},
}
@article {pmid29193223,
year = {2018},
author = {Waller, LP and Felten, J and Hiiesalu, I and Vogt-Schilb, H},
title = {Sharing resources for mutual benefit: crosstalk between disciplines deepens the understanding of mycorrhizal symbioses across scales.},
journal = {The New phytologist},
volume = {217},
number = {1},
pages = {29-32},
doi = {10.1111/nph.14912},
pmid = {29193223},
issn = {1469-8137},
mesh = {Biological Evolution ; Mycorrhizae/*physiology ; Plants/microbiology ; Symbiosis/*physiology ; },
}
@article {pmid31512052,
year = {2019},
author = {Gogoleva, OA and Shchuplova, EA},
title = {The influence of non-tuberculous mycobacteria on the interaction of opportunistic microorganisms with erythrocytes.},
journal = {Folia microbiologica},
volume = {},
number = {},
pages = {},
doi = {10.1007/s12223-019-00748-6},
pmid = {31512052},
issn = {1874-9356},
support = {№ 0420-2015-0005//The work wascarried out within the framework of the state task on the topic &quot;The role of the microbial factor in the functioning of the physiological systems of the human body&quot;/ ; },
abstract = {Getting into a weakened organism, non-tuberculosis mycobacteria (NTMB) contact not only with the cells of the microorganism but also with the microflora of the human body; however, these interactions are poorly understood. The purpose of this work was to study the effect of NTMB supernatants on the properties of conditionally pathogenic microorganisms in their interaction with red blood cells. We used strains of non-tuberculous mycobacteria Mycobacterium iranicum and M. rutilum, as well as strains of Staphylococcus epidermidis and Escherichia coli. Using the fluorescence in situ hybridisation (FISH) method, the processes of adhesion to the surface of erythrocytes and the intra-erythrocyte penetration of cells of S. epidermidis and E. coli under the influence of NTMB supernatants were studied. To study changes in the haemoglobin molecule under the action of the supernatants of NTMB, spectral analysis was performed. Statistical processing was performed using STATISTIKA 6.0. The results showed that the supernatants of M. iranicum and M. rutilum increased the adhesion of conditionally pathogenic bacteria with a low level of AntiHbA to the surface of erythrocytes by 3-4 times. It also increased the intra-erythrocyte penetration of cells of S. epidermidis and E. coli relative to the control values. As a result of studying the haemoglobin spectrum of erythrocytes under the influence of M. iranicum, a decrease in the optical density values of oxyhaemoglobin by a factor of 2 relative to the values in the control sample was noted. Thus, the supernatants of NTMB have a multidirectional effect on the interaction of opportunistic microorganisms with erythrocytes, increasing the adhesive activity and the penetration of cells into the erythrocytes, as well as reducing the optical density of oxyhaemoglobin.},
}
@article {pmid30777324,
year = {2019},
author = {Mellal, H and Yacine, B and Boukaous, L and Khouni, S and Benguedouar, A and Castellano-Hinojosa, A and Bedmar, EJ},
title = {Phylogenetic diversity of Bradyrhizobium strains isolated from root nodules of Lupinus angustifolius grown wild in the North East of Algeria.},
journal = {Systematic and applied microbiology},
volume = {42},
number = {3},
pages = {397-402},
doi = {10.1016/j.syapm.2019.01.003},
pmid = {30777324},
issn = {1618-0984},
mesh = {Algeria ; Bradyrhizobium/*classification/genetics/physiology ; DNA, Bacterial/genetics ; Genes, Bacterial/genetics ; Genes, Essential/genetics ; Host Specificity ; Lupinus/*microbiology ; *Phylogeny ; Plant Root Nodulation ; RNA, Ribosomal, 16S/genetics ; Random Amplified Polymorphic DNA Technique ; Root Nodules, Plant/*microbiology ; Sequence Analysis, DNA ; Symbiosis/genetics ; },
abstract = {From a total of 80 bacterial strains isolated from root nodules of Lupinus angustifolius grown wild in the North-Eastern Algerian region of El Tarf, 64 plant host-nodulating strains clustered into 17 random amplified polymorphic DNA (RAPD) fingerprinting groups. The nearly complete 16S rRNA gene sequence from the representative strain of each group revealed they were closely related to members of the genus Bradyrhizobium of the Alphaproteobacteria, but their affiliation at the species level was not clear. Sequencing of the housekeeping genes glnII and recA, and their concatenated phylogenetic analysis, showed that 12 strains belong to B. lupini, other 2 strains affiliated with B. diazoefficiens and that 1 strain was closely related to B. japonicum. The remaining two strains showed similarity values ≤95% with B. cytisi and could represent new lineages within the genus Bradyrhizobium. Sequencing of the symbiotic nodC gene from 4 selected bradyrhizobial strains showed they were all similar to those of the species included in symbiovar genistearum.},
}
@article {pmid30487259,
year = {2018},
author = {Harrison, TL and Simonsen, AK and Stinchcombe, JR and Frederickson, ME},
title = {More partners, more ranges: generalist legumes spread more easily around the globe.},
journal = {Biology letters},
volume = {14},
number = {11},
pages = {},
pmid = {30487259},
issn = {1744-957X},
mesh = {Fabaceae/microbiology/*physiology ; *Plant Dispersal ; RNA, Bacterial/analysis ; RNA, Ribosomal, 16S/analysis ; Rhizobium/genetics/*physiology ; *Symbiosis ; },
abstract = {How does mutualism affect range expansion? On the one hand, mutualists might thrive in new habitats thanks to the resources, stress tolerance or defence provided by their partners. On the other, specialized mutualists might fail to find compatible partners beyond their range margins, limiting further spread. A recent global analysis of legume ranges found that non-symbiotic legumes have been successfully introduced to more ranges than legumes that form symbioses with rhizobia, but there is still abundant unexplained variation in introduction success within symbiotic legumes. We test the hypothesis that generalist legumes have spread to more ranges than specialist legumes. We used published data and rhizobial 16S rRNA sequences from GenBank to quantify the number of rhizobia partners that associate with 159 legume species, spanning the legume phylogeny and the globe. We found that generalist legumes occur in more introduced ranges than specialist legumes, suggesting that among mutualists, specialization hinders range expansions.},
}
@article {pmid30381384,
year = {2018},
author = {Palmer-Young, EC and Raffel, TR and McFrederick, QS},
title = {Temperature-mediated inhibition of a bumblebee parasite by an intestinal symbiont.},
journal = {Proceedings. Biological sciences},
volume = {285},
number = {1890},
pages = {},
pmid = {30381384},
issn = {1471-2954},
support = {R01 GM122062/GM/NIGMS NIH HHS/United States ; },
mesh = {Animals ; Bees/microbiology/parasitology ; Coculture Techniques ; Crithidia/drug effects/*growth &amp; development ; Lactobacillus/*growth &amp; development/metabolism ; Symbiosis/physiology ; *Temperature ; },
abstract = {Competition between organisms is often mediated by environmental factors, including temperature. In animal intestines, nonpathogenic symbionts compete physically and chemically against pathogens, with consequences for host infection. We used metabolic theory-based models to characterize differential responses to temperature of a bacterial symbiont and a co-occurring trypanosomatid parasite of bumblebees, which regulate body temperature during flight and incubation. We hypothesized that inhibition of parasites by bacterial symbionts would increase with temperature, due to symbionts having higher optimal growth temperatures than parasites. We found that a temperature increase over the range measured in bumblebee colonies would favour symbionts over parasites. As predicted by our hypothesis, symbionts reduced the optimal growth temperature for parasites, both in direct competition and when parasites were exposed to symbiont spent medium. Inhibitory effects of the symbiont increased with temperature, reflecting accelerated growth and acid production by symbionts. Our results indicate that high temperatures, whether due to host endothermy or environmental factors, can enhance the inhibitory effects of symbionts on parasites. Temperature-modulated manipulation of microbiota could be one explanation for fever- and heat-induced reductions of infection in animals, with consequences for diseases of medical and conservation concern.},
}
@article {pmid29034959,
year = {2018},
author = {Helliwell, KE and Pandhal, J and Cooper, MB and Longworth, J and Kudahl, UJ and Russo, DA and Tomsett, EV and Bunbury, F and Salmon, DL and Smirnoff, N and Wright, PC and Smith, AG},
title = {Quantitative proteomics of a B12 -dependent alga grown in coculture with bacteria reveals metabolic tradeoffs required for mutualism.},
journal = {The New phytologist},
volume = {217},
number = {2},
pages = {599-612},
pmid = {29034959},
issn = {1469-8137},
support = {BB/F011652/1//Biotechnology and Biological Sciences Research Council/United Kingdom ; BB/I013164/1//Biotechnology and Biological Sciences Research Council/United Kingdom ; },
mesh = {Algal Proteins/metabolism ; Amino Acids/metabolism ; Chlorophyta/drug effects/genetics/*growth &amp; development/*metabolism ; Coculture Techniques ; Computational Biology ; Electron Transport/drug effects ; Gene Expression Regulation, Plant/drug effects ; Mesorhizobium/drug effects/*growth &amp; development ; Photosynthesis/drug effects ; *Proteomics ; RNA, Messenger/genetics/metabolism ; Symbiosis/*drug effects ; Vitamin B 12/*pharmacology ; },
abstract = {The unicellular green alga Lobomonas rostrata requires an external supply of vitamin B12 (cobalamin) for growth, which it can obtain in stable laboratory cultures from the soil bacterium Mesorhizobium loti in exchange for photosynthate. We investigated changes in protein expression in the alga that allow it to engage in this mutualism. We used quantitative isobaric tagging (iTRAQ) proteomics to determine the L. rostrata proteome grown axenically with B12 supplementation or in coculture with M. loti. Data are available via ProteomeXchange (PXD005046). Using the related Chlamydomonas reinhardtii as a reference genome, 588 algal proteins could be identified. Enzymes of amino acid biosynthesis were higher in coculture than in axenic culture, and this was reflected in increased amounts of total cellular protein and several free amino acids. A number of heat shock proteins were also elevated. Conversely, photosynthetic proteins and those of chloroplast protein synthesis were significantly lower in L. rostrata cells in coculture. These observations were confirmed by measurement of electron transfer rates in cells grown under the two conditions. The results indicate that, despite the stability of the mutualism, L. rostrata experiences stress in coculture with M. loti, and must adjust its metabolism accordingly.},
}
@article {pmid31509600,
year = {2019},
author = {Radice, VZ and Brett, MT and Fry, B and Fox, MD and Hoegh-Guldberg, O and Dove, SG},
title = {Evaluating coral trophic strategies using fatty acid composition and indices.},
journal = {PloS one},
volume = {14},
number = {9},
pages = {e0222327},
doi = {10.1371/journal.pone.0222327},
pmid = {31509600},
issn = {1932-6203},
abstract = {The ecological success of shallow water reef-building corals has been linked to the symbiosis between the coral host and its dinoflagellate symbionts (herein 'symbionts'). As mixotrophs, symbiotic corals depend on nutrients 1) transferred from their photosynthetic symbionts (autotrophy) and 2) acquired by host feeding on particulate organic resources (heterotrophy). However, coral species differ in the extent to which they depend on heterotrophy for nutrition and these differences are typically poorly defined. Here, a multi-tracer fatty acid approach was used to evaluate the trophic strategies of three species of common reef-building coral (Galaxea fascicularis, Pachyseris speciosa, and Pocillopora verrucosa) whose trophic strategies had previously been identified using carbon stable isotopes. The composition and various indices of fatty acids were compared to examine the relative contribution of symbiont autotrophy and host heterotrophy in coral energy acquisition. A linear discriminant analysis (LDA) was used to estimate the contribution of polyunsaturated fatty acids (PUFA) derived from various potential sources to the coral hosts. The total fatty acid composition and fatty acid indices revealed differences between the more heterotrophic (P. verrucosa) and more autotrophic (P. speciosa) coral hosts, with the coral host G. fascicularis showing overlap with the other two species and greater variability overall. For the more heterotrophic P. verrucosa, the fatty acid indices and LDA results both indicated a greater proportion of copepod-derived fatty acids compared to the other coral species. Overall, the LDA estimated that PUFA derived from particulate resources (e.g., copepods and diatoms) comprised a greater proportion of coral host PUFA in contrast to the lower proportion of symbiont-derived PUFA. These estimates provide insight into the importance of heterotrophy in coral nutrition, especially in productive reef systems. The study supports carbon stable isotope results and demonstrates the utility of fatty acid analyses for exploring the trophic strategies of reef-building corals.},
}
@article {pmid31508195,
year = {2019},
author = {He, S and Grasis, JA and Nicotra, ML and Juliano, CE and Schnitzler, CE},
title = {Cnidofest 2018: the future is bright for cnidarian research.},
journal = {EvoDevo},
volume = {10},
number = {},
pages = {20},
doi = {10.1186/s13227-019-0134-5},
pmid = {31508195},
issn = {2041-9139},
abstract = {The 2018 Cnidarian Model Systems Meeting (Cnidofest) was held September 6-9th at the University of Florida Whitney Laboratory for Marine Bioscience in St. Augustine, FL. Cnidofest 2018, which built upon the momentum of Hydroidfest 2016, brought together research communities working on a broad spectrum of cnidarian organisms from North America and around the world. Meeting talks covered diverse aspects of cnidarian biology, with sessions focused on genomics, development, neurobiology, immunology, symbiosis, ecology, and evolution. In addition to interesting biology, Cnidofest also emphasized the advancement of modern research techniques. Invited technology speakers showcased the power of microfluidics and single-cell transcriptomics and demonstrated their application in cnidarian models. In this report, we provide an overview of the exciting research that was presented at the meeting and discuss opportunities for future research.},
}
@article {pmid31504077,
year = {2017},
author = {Dupre, C and Grasis, JA and Steele, RE and Schnitzler, CE and Juliano, CE},
title = {Hydroidfest 2016: celebrating a renaissance in hydrozoan research.},
journal = {EvoDevo},
volume = {8},
number = {},
pages = {7},
doi = {10.1186/s13227-017-0070-1},
pmid = {31504077},
issn = {2041-9139},
abstract = {Hydroidfest 2016 took place on September 23-25 at the UC Davis Bodega Marine Laboratory in Bodega Bay, CA. The meeting brought together cnidarian researchers, with an emphasis on those studying hydrozoans, from North America and other parts of the world. The scientific topics discussed were diverse, including sessions focused on development, regeneration, aging, immunology, symbiosis, and neurobiology. Thanks to the application of modern biological technologies, hydrozoans and other cnidarians are now fertile ground for research in numerous disciplines. Moreover, their amenability to comparative approaches is a powerful asset that was repeatedly showcased during the meeting. Here, we give a brief account of the work that was presented and the opportunities that emerged from the ensuing discussions.},
}
@article {pmid31504533,
year = {2019},
author = {Havird, JC and Weaver, RJ and Milani, L and Ghiselli, F and Greenway, R and Ramsey, AJ and Jimenez, AG and Dowling, DK and Hood, WR and Montooth, KL and Estes, S and Schulte, PM and Sokolova, IM and Hill, GE},
title = {Beyond the Powerhouse: Integrating Mitonuclear Evolution, Physiology, and Theory in Comparative Biology.},
journal = {Integrative and comparative biology},
volume = {},
number = {},
pages = {},
doi = {10.1093/icb/icz132},
pmid = {31504533},
issn = {1557-7023},
abstract = {Eukaryotes are the outcome of an ancient symbiosis and as such, eukaryotic cells fundamentally possess two genomes. As a consequence, gene products encoded by both nuclear and mitochondrial genomes must interact in an intimate and precise fashion to enable aerobic respiration in eukaryotes. This genomic architecture of eukaryotes is proposed to necessitate perpetual coevolution between the nuclear and mitochondrial genomes to maintain coadaptation, but the presence of two genomes also creates the opportunity for intracellular conflict. In the collection of papers that constitute this symposium volume, scientists working in diverse organismal systems spanning vast biological scales address emerging topics in integrative, comparative biology in light of mitonuclear interactions.},
}
@article {pmid31504465,
year = {2019},
author = {Freed, LL and Easson, C and Baker, LJ and Fenolio, D and Sutton, TT and Khan, Y and Blackwelder, P and Hendry, TA and Lopez, JV},
title = {Characterization of the microbiome and bioluminescent symbionts across life stages of ceratioid anglerfishes of the gulf of mexico.},
journal = {FEMS microbiology ecology},
volume = {},
number = {},
pages = {},
doi = {10.1093/femsec/fiz146},
pmid = {31504465},
issn = {1574-6941},
abstract = {The interdependence of diverse organisms through symbiosis reaches even the deepest parts of the oceans. As part of the DEEPEND project (deependconsortium.org) research on deep Gulf of Mexico biodiversity, we profiled the bacterial communities ('microbiomes') and luminous symbionts of 36 specimens of adult and larval deep-sea anglerfishes of the suborder Ceratioidei using 16S rDNA. Transmission Electron Microscopy was used to characterize the location of symbionts in adult light organs (esca). Whole larval microbiomes, and adult skin and gut microbiomes, were dominated by bacteria in the genera Moritella and Pseudoalteromonas genera. 16S rDNA sequencing results from adult fishes corroborate the previously published identity of ceratioid bioluminescent symbionts and support findings that these symbionts do not consistently exhibit host specificity at the host family level. Bioluminescent symbiont amplicon sequence variants (ASVs) were absent from larval ceratioid samples, but were found at all depths in the seawater, with a highest abundance found at mesopelagic depths. As adults spend the majority of their lives in the meso and bathypelagic, the trend in symbiont abundance is consistent with their life history. These findings support the hypothesis that bioluminescent symbionts are not present throughout host development, and that ceratioids acquire their bioluminescent symbionts from the environment.},
}
@article {pmid31504453,
year = {2019},
author = {Barelli, L and Behie, SW and Bidochka, MJ},
title = {Availability of carbon and nitrogen in soil affects Metarhizium robertsii root colonization and transfer of insect-derived nitrogen.},
journal = {FEMS microbiology ecology},
volume = {},
number = {},
pages = {},
doi = {10.1093/femsec/fiz144},
pmid = {31504453},
issn = {1574-6941},
abstract = {The endophytic, insect pathogenic fungus, Metarhizium, exchanges insect-derived nitrogen for photosynthate as part of a symbiotic association similar to well-known mycorrhizal relationships. However, little is known about this nitrogen transfer in soils where there is an abundance of nitrogen and/or carbon. Here we applied D-glucose and ammonium nitrate to soil to examine the effect on root colonization and transfer of labelled nitrogen (15N) from an insect (injected with 15N-ammonium sulfate), to Metarhizium robertsii, into leaves of the common bean, Phaseolus vulgaris, over the course of 28 days. Application of exogenous carbon and/or nitrogen to soils significantly reduced detectable 15N in plant leaves. Metarhizium root colonization, quantified with real-time PCR, revealed colonization persisted under all conditions but was significantly greater on roots in soil supplemented with glucose and significantly lower in soil supplemented with ammonium nitrate. Fungal gene expression analysis revealed differential expression of sugar and nitrogen transporters (mrt, st3, nrr1, nit1, mep2) when Metarhizium was grown in pure broth culture or in co-culture with plant roots under various carbon and nitrogen conditions. The observation that Metarhizium maintained root colonization in the absence of nitrogen transfer, and without evidence of plant harm, is intriguing and indicates additional benefits with ecological importance.},
}
@article {pmid31500535,
year = {2019},
author = {Foster, RA and Zehr, JP},
title = {Diversity, Genomics, and Distribution of Phytoplankton-Cyanobacterium Single-Cell Symbiotic Associations.},
journal = {Annual review of microbiology},
volume = {73},
number = {},
pages = {435-456},
doi = {10.1146/annurev-micro-090817-062650},
pmid = {31500535},
issn = {1545-3251},
abstract = {Cyanobacteria are common in symbiotic relationships with diverse multicellular organisms (animals, plants, fungi) in terrestrial environments and with single-celled heterotrophic, mixotrophic, and autotrophic protists in aquatic environments. In the sunlit zones of aquatic environments, diverse cyanobacterial symbioses exist with autotrophic taxa in phytoplankton, including dinoflagellates, diatoms, and haptophytes (prymnesiophytes). Phototrophic unicellular cyanobacteria related to Synechococcus and Prochlorococcus are associated with a number of groups. N2-fixing cyanobacteria are symbiotic with diatoms and haptophytes. Extensive genome reduction is involved in the N2-fixing endosymbionts, most dramatically in the unicellular cyanobacteria associated with haptophytes, which have lost most of the photosynthetic apparatus, the ability to fix C, and the tricarboxylic acid cycle. The mechanisms involved in N2-fixing symbioses may involve more interactions beyond simple exchange of fixed C for N. N2-fixing cyanobacterial symbioses are widespread in the oceans, even more widely distributed than the best-known free-living N2-fixing cyanobacteria, suggesting they may be equally or more important in the global ocean biogeochemical cycle of N.Despite their ubiquitous nature and significance in biogeochemical cycles, cyanobacterium-phytoplankton symbioses remain understudied and poorly understood.},
}
@article {pmid31185402,
year = {2019},
author = {Parvin, S and Van Geel, M and Yeasmin, T and Lievens, B and Honnay, O},
title = {Variation in arbuscular mycorrhizal fungal communities associated with lowland rice (Oryza sativa) along a gradient of soil salinity and arsenic contamination in Bangladesh.},
journal = {The Science of the total environment},
volume = {686},
number = {},
pages = {546-554},
doi = {10.1016/j.scitotenv.2019.05.450},
pmid = {31185402},
issn = {1879-1026},
mesh = {Arsenic/*analysis ; Bangladesh ; Environmental Monitoring ; Mycobiome ; Mycorrhizae/*growth &amp; development ; Oryza/*microbiology/physiology ; Soil/chemistry ; Soil Microbiology ; Soil Pollutants/*analysis ; Symbiosis ; },
abstract = {Rice is an essential food crop that nourishes >50% of the world population. In many regions of Bangladesh rice production is constrained by high soil salinity and heavy metal contamination due to irrigation practices. Plants may naturally overcome such stress through mutualistic interactions with arbuscular mycorrhizal fungi (AMF). Yet, little is known regarding the diversity and composition of AMF communities in rice fields with high saline and arsenic concentration. Here we used high throughput Illumina sequencing to characterize AMF communities in rice roots from 45 Bangladeshi rice fields, along a large geographical gradient of soil salinity and arsenic contamination. We obtained 77 operational taxonomic units (OTUs, based on a sequence similarity threshold of 97%) from eight AMF families, and showed that high soil salinity and arsenic concentration are significantly associated with low AMF diversity in rice roots. Soil salinity and arsenic concentration also explained a large part of the variation in AMF community composition, but also soil pH, moisture, organic matter content and plant available soil phosphorus played an important role. Overall, our study showed that even at very high salinity and arsenic levels, some AMF OTUs are present in rice roots. Their potential role in mediating a reduction of rice stress and arsenic uptake remains to be investigated.},
}
@article {pmid31101011,
year = {2019},
author = {Zhang, Y and Chen, Q and Xie, JY and Yeung, YH and Xiao, B and Liao, B and Xu, J and Qiu, JW},
title = {Development of a transcriptomic database for 14 species of scleractinian corals.},
journal = {BMC genomics},
volume = {20},
number = {1},
pages = {387},
doi = {10.1186/s12864-019-5744-8},
pmid = {31101011},
issn = {1471-2164},
support = {JCYJ20170307161326613//Shenzhen Science and Technology Innovation Committee (CN)/ ; 2017-03//Environment and Conservation Fund, Hong Kong/ ; 12102018//General Research Fund of Hong Kong/ ; },
mesh = {Animals ; Anthozoa/*classification/*genetics ; Computational Biology/*methods ; *Databases, Genetic ; High-Throughput Nucleotide Sequencing ; *Molecular Sequence Annotation ; Symbiosis ; *Transcriptome ; },
abstract = {BACKGROUND: Scleractinian corals are important reef builders, but around the world they are under the threat of global climate change as well as local stressors. Molecular resources are critical for understanding a species' stress responses and resilience to the changing environment, but such resources are unavailable for most scleractinian corals, especially those distributed in the South China Sea. We therefore aimed to provide transcriptome resources for 14 common species, including a few structure forming species, in the South China Sea.<br><br>DESCRIPTION: We sequenced the transcriptome of 14 species of scleractinian corals using high-throughput RNA-seq and conducted de novo assembly. For each species, we produced 7.4 to 12.0 gigabases of reads, and assembled them into 271 to 762 thousand contigs with a N50 value of 629 to 1427 bp. These contigs included 66 to 114 thousand unigenes with a predicted open reading frame, and 74.3 to 80.5% of the unigenes were functionally annotated. In the azooxanthelate species Tubastraea coccinea, 41.5% of the unigenes had at least a best-hit sequence from corals. In the other thirteen species, 20.2 to 48.9% of the annotated unigenes had best-hit sequences from corals, and 28.3 to 51.6% from symbiotic algae belonging to the family Symbiodinaceae. With these resources, we developed a transcriptome database (CoralTBase) which features online BLAST and keyword search for unigenes/functional terms through a user friendly Internet interface.<br><br>SHORT CONCLUSION: We developed comprehensive transcriptome resources for 14 species of scleractinian corals and constructed a publicly accessible database (www.comp.hkbu.edu.hk/~db/CoralTBase). CoralTBase will facilitate not only functional studies using these corals to understand the molecular basis of stress responses and adaptation, but also comparative transcriptomic studies with other species of corals and more distantly related cnidarians.},
}
@article {pmid30857983,
year = {2019},
author = {Wu, Y and Zhou, Z and Wang, J and Luo, J and Wang, L and Zhang, Y},
title = {Temperature regulates the recognition activities of a galectin to pathogen and symbiont in the scleractinian coral Pocillopora damicornis.},
journal = {Developmental and comparative immunology},
volume = {96},
number = {},
pages = {103-110},
doi = {10.1016/j.dci.2019.03.003},
pmid = {30857983},
issn = {1879-0089},
mesh = {Amino Acid Sequence ; Animals ; Anthozoa/*immunology/microbiology ; Cloning, Molecular ; Coral Reefs ; Escherichia coli/immunology ; Galectins/genetics/*immunology/metabolism ; Host Microbial Interactions/*immunology ; Recombinant Proteins/genetics/immunology/metabolism ; Sequence Homology, Amino Acid ; Streptococcus mutans/immunology ; Symbiosis/*immunology ; *Temperature ; Vibrio/immunology ; },
abstract = {Lectins serve as essential pattern recognition receptors, and play important roles in the recognition of non-self and mediation of innate immune response in metazoans. Scleractinian corals are vulnerable to pathogen infection and endosymbiosis disruption under heat stress that can finally lead to coral bleaching. In this study, a cDNA sequence encoding one galectin was cloned in scleractinian coral Pocillopora damicornis (PdGLT-1). The deduced PdGLT-1 protein shared highest amino acid sequence similarity (99%) with galectin from Stylophora pistillata (XP_022806650.1), and was composed of one signal peptide, one Collagen domain and one Gal-Lectin domain. PdGLT-1 recombinant protein (rPdGLT-1) was expressed and purified in vitro. Binding activities of rPdGLT-1 to bacteria and symbiont were determined using western blotting method. Results showed that rPdGLT-1 was able to bind to gram-positive bacterium Streptococcus mutans, gram-negative bacteria Vibrio coralliilyticus and Escherichia coli, with the highest activity for V. coralliilyticus, and further agglutinated them. The bound rPdGLT-1 to Symbiodinium (10-104 cells mL-1) was detectable, and its binding ability was concentration-dependent. Furthermore, dual binding activities were determined under different temperatures (20, 25, 30 and 35 °C), and the optimal temperatures were found to be 25 and 30 °C for V. coralliilyticus and Symbiodinium, respectively. Results suggested that PdGLT-1 could recognize pathogenic bacteria and symbiotic dinoflagellates Symbiodinium. However, their recognition activities were repressed under high temperature (>30 °C). This study provided insights into the underlying mechanism of lectin modulation to heat bleaching through its pathogen and Symbiodinium recognition in the scleractinian coral P. damicornis.},
}
@article {pmid30719426,
year = {2018},
author = {Myles, IA and Moore, IN and Castillo, CR and Datta, SK},
title = {Differing Virulence of Healthy Skin Commensals in Mouse Models of Infection.},
journal = {Frontiers in cellular and infection microbiology},
volume = {8},
number = {},
pages = {451},
doi = {10.3389/fcimb.2018.00451},
pmid = {30719426},
issn = {2235-2988},
mesh = {Animals ; Bacterial Infections/*microbiology/pathology ; Carrier State/microbiology ; Disease Models, Animal ; Methylobacteriaceae/*growth &amp; development/pathogenicity ; Mice ; Probiotics/administration &amp; dosage/*adverse effects ; Pseudomonas aeruginosa/*growth &amp; development/pathogenicity ; Staphylococcus/*growth &amp; development/pathogenicity ; *Symbiosis ; *Virulence ; },
abstract = {Introduction: As therapies for atopic dermatitis (AD) based on live biotherapeutic products (LBP) are developed, the potential displacement of biotherapeutic strains, and species to mucosal sites where they are not naturally found is of investigative interest. However, formal assessment of the toxicity potential of healthy skin commensal organisms has not been reported in the literature. Our previous research indicates that topical application of live Roseomonas mucosa to treat AD was associated with clinical benefit on the skin, but the effects of exposure via inhalation, eye inoculation, and ingestion were unknown. Methods: Herein we report our findings from mice inoculated with commensal strains of R. mucosa, coagulase negative Staphylococci (CNS), and Pseudomonas aeruginosa. Bacterial isolates were collected under clinical trial NCT03018275, however these results do not represent an interventional clinical trial. Results: Our tested R. mucosa isolates did not display significant infection or inflammation. However, neutropenic mice inoculated with CNS had infection without major inflammation in pulmonary models. In contrast, systemic infection generated hepatic and splenic pathology for P. aeruginosa and CNS, which was worsened by the presence of neutropenia. Discussion: Our results suggest that LBP derived from bacteria without significant infectivity histories, such as R. mucosa, may represent safer options than known pathobionts like P. aeruginosa and Staphylococcus spp. Overall, these results suggest that topically applied LBP from select skin commensals are likely to present safe therapeutic options and reinforce our prior clinical findings.},
}
@article {pmid31497392,
year = {2019},
author = {Shtark, OY and Puzanskiy, RK and Avdeeva, GS and Yurkov, AP and Smolikova, GN and Yemelyanov, VV and Kliukova, MS and Shavarda, AL and Kirpichnikova, AA and Zhernakov, AI and Afonin, AM and Tikhonovich, IA and Zhukov, VA and Shishova, MF},
title = {Metabolic alterations in pea leaves during arbuscular mycorrhiza development.},
journal = {PeerJ},
volume = {7},
number = {},
pages = {e7495},
doi = {10.7717/peerj.7495},
pmid = {31497392},
issn = {2167-8359},
abstract = {Arbuscular mycorrhiza (AM) is known to be a mutually beneficial plant-fungal symbiosis; however, the effect of mycorrhization is heavily dependent on multiple biotic and abiotic factors. Therefore, for the proper employment of such plant-fungal symbiotic systems in agriculture, a detailed understanding of the molecular basis of the plant developmental response to mycorrhization is needed. The aim of this work was to uncover the physiological and metabolic alterations in pea (Pisum sativum L.) leaves associated with mycorrhization at key plant developmental stages. Plants of pea cv. Finale were grown in constant environmental conditions under phosphate deficiency. The plants were analyzed at six distinct time points, which corresponded to certain developmental stages of the pea: I: 7 days post inoculation (DPI) when the second leaf is fully unfolded with one pair of leaflets and a simple tendril; II: 21 DPI at first leaf with two pairs of leaflets and a complex tendril; III: 32 DPI when the floral bud is enclosed; IV: 42 DPI at the first open flower; V: 56 DPI when the pod is filled with green seeds; and VI: 90-110 DPI at the dry harvest stage. Inoculation with Rhizophagus irregularis had no effect on the fresh or dry shoot weight, the leaf photochemical activity, accumulation of chlorophyll a, b or carotenoids. However, at stage III (corresponding to the most active phase of mycorrhiza development), the number of internodes between cotyledons and the youngest completely developed leaf was lower in the inoculated plants than in those without inoculation. Moreover, inoculation extended the vegetation period of the host plants, and resulted in increase of the average dry weight per seed at stage VI. The leaf metabolome, as analyzed with GC-MS, included about three hundred distinct metabolites and showed a strong correlation with plant age, and, to a lesser extent, was influenced by mycorrhization. Metabolic shifts influenced the levels of sugars, amino acids and other intermediates of nitrogen and phosphorus metabolism. The use of unsupervised dimension reduction methods showed that (i) at stage II, the metabolite spectra of inoculated plants were similar to those of the control, and (ii) at stages IV and V, the leaf metabolic profiles of inoculated plants shifted towards the profiles of the control plants at earlier developmental stages. At stage IV the inoculated plants exhibited a higher level of metabolism of nitrogen, organic acids, and lipophilic compounds in comparison to control plants. Thus, mycorrhization led to the retardation of plant development, which was also associated with higher seed biomass accumulation in plants with an extended vegetation period. The symbiotic crosstalk between host plant and AM fungi leads to alterations in several biochemical pathways the details of which need to be elucidated in further studies.},
}
@article {pmid31495588,
year = {2019},
author = {Iwai, S and Fujita, K and Takanishi, Y and Fukushi, K},
title = {Photosynthetic Endosymbionts Benefit from Host's Phagotrophy, Including Predation on Potential Competitors.},
journal = {Current biology : CB},
volume = {},
number = {},
pages = {},
doi = {10.1016/j.cub.2019.07.074},
pmid = {31495588},
issn = {1879-0445},
abstract = {In many endosymbioses, hosts have been shown to benefit from symbiosis, but it remains unclear whether intracellular endosymbionts benefit from their association with hosts [1, 2]. This makes it difficult to determine evolutionary mechanisms underlying cooperative behaviors between hosts and intracellular endosymbionts, such as mutual exchange of vital resources. Here, we investigate the fitness effects of symbiosis on the ciliate host Paramecium bursaria and on the algal endosymbiont Chlorella [3, 4], using experimental microcosms that include the free-living alga Chlamydomonas reinhardtii to mimic ecologically realistic conditions. We demonstrate that both host ciliate and the endosymbiotic algae gain fitness benefits from the symbiosis when another alga C. reinhardtii is present in the system. Specifically, the endosymbiotic Chlorella can grow as the host ciliate feeds and grows on C. reinhardtii, whereas the growth of free-living Chlorella is reduced by its competitor, C. reinhardtii. Thus, we propose that the endosymbiotic algae benefit from the host's phagotrophy, which allows the endosymbiont to access particulate nutrient sources and to indirectly prey on the potential competitors competing with its free-living counterparts. Even though the ecological contexts in which each partner receives its benefits differ, both partners would gain net fitness benefits in an ecological timescale. Thus, the cooperative behaviors can evolve through fitness feedback (partner fidelity feedback) between the host and the endosymbiont, without need for special partner control mechanisms. The proposed ecological and evolutionary mechanisms provide a basis for understanding cooperative resource exchanges in endosymbioses, including many photosynthetic endosymbioses widespread in aquatic ecosystems.},
}
@article {pmid31166161,
year = {2019},
author = {Sazanova, AL and Safronova, VI and Kuznetsova, IG and Karlov, DS and Belimov, AA and Andronov, EE and Chirak, ER and Popova, JP and Verkhozina, AV and Willems, A and Tikhonovich, IA},
title = {Bosea caraganae sp. nov. a new species of slow-growing bacteria isolated from root nodules of the relict species Caragana jubata (Pall.) Poir. originating from Mongolia.},
journal = {International journal of systematic and evolutionary microbiology},
volume = {69},
number = {9},
pages = {2687-2695},
doi = {10.1099/ijsem.0.003509},
pmid = {31166161},
issn = {1466-5034},
mesh = {Bacterial Typing Techniques ; Base Composition ; Bradyrhizobiaceae/*classification/isolation &amp; purification ; Caragana/*microbiology ; DNA, Bacterial/genetics ; Fatty Acids/chemistry ; Genes, Bacterial ; Mongolia ; *Phylogeny ; RNA, Ribosomal, 16S/genetics ; Root Nodules, Plant/*microbiology ; Sequence Analysis, DNA ; Symbiosis ; },
abstract = {Two Gram-stain-negative strains, RCAM04680T and RCAM04685, were isolated from root nodules of the relict legume Caragana jubata (Pall.) Poir. originating from the south-western shore of Lake Khuvsgul (Mongolia). The 16S rRNA gene (rrs) sequencing data showed that these novel isolates belong to the genus Bosea and are phylogenetically closest to the type strains Bosea lathyri LMG 26379T, Bosea vaviloviae LMG 28367T, Bosea massiliensis LMG 26221T and Bosea lupini LMG 26383T (the rrs-similarity levels were 98.7-98.8 %). The recA gene of strain RCAM04680T showed the highest sequence similarity to the type strain B. lupini LMG 26383T (95.4 %), while its atpD gene was closest to that of B. lathyri LMG 26379T (94.4 %). The ITS, dnaK and gyrB sequences of this isolate were most similar to the B. vaviloviae LMG 28367T (86.8 % for ITS, 90.4 % for the other genes). The most abundant fatty acid was C18 : 1ω7c (40.8 %). The whole genomes of strains RCAM04680T and RCAM04685 were identical (100 % average nucleotide identity). The highest average nucleotide identity value (82.8 %) was found between the genome of strain RCAM04680T and B. vaviloviae LMG 28367T. The common nodABC genes required for legume nodulation were absent in both strains; however, some other symbiotic nol, nod, nif and fix genes were detected. Based on the genetic study, as well as analyses of the whole-cell fatty acid compositions and phenotypic properties, a new species, Boseacaraganae sp. nov. (type strain RCAM04680T (=LMG 31125T), is proposed.},
}
@article {pmid30904535,
year = {2019},
author = {Javaheri-Kermani, M and Asoodeh, A},
title = {A novel beta-1,4 glucanase produced by symbiotic Bacillus sp. CF96 isolated from termite (Anacanthotermes).},
journal = {International journal of biological macromolecules},
volume = {131},
number = {},
pages = {752-759},
doi = {10.1016/j.ijbiomac.2019.03.124},
pmid = {30904535},
issn = {1879-0003},
mesh = {Animals ; Bacillus/classification/*enzymology/genetics/isolation &amp; purification ; Chemical Phenomena ; Chromatography, Thin Layer ; Enzyme Activation ; Enzyme Stability ; Glycoside Hydrolases/*chemistry/*isolation &amp; purification/metabolism ; Hydrogen-Ion Concentration ; Hydrolysis ; Isoptera/*microbiology ; Solvents ; Substrate Specificity ; Symbiosis ; Temperature ; },
abstract = {A novel beta-1,4-glucanase was purified and characterized from symbiotic Bacillus sp. CF96 of termite. The SDS-PAGE and zymogram analyses revealed a molecular mass of 35.6 kDa. Optimal activity was at 50 °C and pH 5.5, while the enzyme was active over a wide range of temperature 20-80 °C and pH 4-10 and interestingly more than 60% of the maximum activity remained up to pH 9. The enzyme activity increased in the presence of hexane, chloroform and methanol (20% v/v). while, the enzyme activity was inhibited by metal ions such as Mn2+, Hg2+, Cu2+, Zn2+, Mg2+, Fe2+. The isolated enzyme was able to degrade carboxymethyl cellulose (CMC), avicel and cellulose. Cellobiose was the hydrolytic product of enzymatic reaction based on thin layer chromatography (TLC) analysis. Regarding beta-1,4 endo/exoglucanase activity and high temperature, pH and solvent stability, the enzyme has potential for various industrial applications especially in designing pesticide for termite.},
}
@article {pmid30246365,
year = {2018},
author = {Murakami, T and Segawa, T and Takeuchi, N and Barcaza Sepúlveda, G and Labarca, P and Kohshima, S and Hongoh, Y},
title = {Metagenomic analyses highlight the symbiotic association between the glacier stonefly Andiperla willinki and its bacterial gut community.},
journal = {Environmental microbiology},
volume = {20},
number = {11},
pages = {4170-4183},
doi = {10.1111/1462-2920.14420},
pmid = {30246365},
issn = {1462-2920},
support = {16H04840//Japan Society for the Promotion of Science/International ; 17K19423//Japan Society for the Promotion of Science/International ; 22241005//Japan Society for the Promotion of Science/International ; 23117003//Japan Society for the Promotion of Science/International ; 26241020//Japan Society for the Promotion of Science/International ; GS009//NEXT/International ; },
mesh = {Animals ; Bacteria/classification/*genetics/*isolation &amp; purification ; Bacterial Physiological Phenomena ; Ecosystem ; *Gastrointestinal Microbiome ; Gastrointestinal Tract/microbiology ; Ice Cover/*parasitology ; In Situ Hybridization, Fluorescence ; Insecta/*microbiology/physiology ; Metagenomics ; RNA, Ribosomal, 16S/genetics ; *Symbiosis ; },
abstract = {The glacier stonefly Andiperla willinki is the largest metazoan inhabiting the Patagonian glaciers. In this study, we analysed the gut microbiome of the aquatic nymphs by 16S rRNA gene amplicon and metagenomic sequencing. The bacterial gut community was consistently dominated by taxa typical of animal digestive tracts, such as Dysgonomonadaceae and Lachnospiraceae, as well as those generally indigenous to glacier environments, such as Polaromonas. Interestingly, the dominant Polaromonas phylotypes detected in the stonefly gut were almost never detected in the glacier surface habitat. Fluorescence in situ hybridization analysis revealed that the bacterial lineages typical of animal guts colonized the gut wall in a co-aggregated form, while Polaromonas cells were not included in the aggregates. Draft genomes of several dominant bacterial lineages were reconstructed from metagenomic datasets and indicated that the predominant Dysgonomonadaceae bacterium is capable of degrading various polysaccharides derived from host-ingested food, such as algae, and that other dominant bacterial lineages ferment saccharides liberated by the polysaccharide degradation. Our results suggest that the gut bacteria-host association in the glacier stonefly contributes to host nutrition as well as material cycles in the glacier environment.},
}
@article {pmid30062595,
year = {2019},
author = {Kapitan, M and Niemiec, MJ and Steimle, A and Frick, JS and Jacobsen, ID},
title = {Fungi as Part of the Microbiota and Interactions with Intestinal Bacteria.},
journal = {Current topics in microbiology and immunology},
volume = {422},
number = {},
pages = {265-301},
doi = {10.1007/82_2018_117},
pmid = {30062595},
issn = {0070-217X},
mesh = {*Bacteria ; Bacterial Infections/microbiology ; Candida albicans/pathogenicity/physiology ; Fungi/pathogenicity/*physiology ; Gastrointestinal Microbiome/*physiology ; Humans ; *Microbial Interactions ; Symbiosis ; },
abstract = {The human microbiota consists of bacteria, archaea, viruses, and fungi that build a highly complex network of interactions between each other and the host. While there are many examples for commensal bacterial influence on host health and immune modulation, little is known about the role of commensal fungi inside the gut community. Up until now, fungal research was concentrating on opportunistic diseases caused by fungal species, leaving the possible role of fungi as part of the microbiota largely unclear. Interestingly, fungal and bacterial abundance in the gut appear to be negatively correlated and disruption of the bacterial microbiota is a prerequisite for fungal overgrowth. The mechanisms behind bacterial colonization resistance are likely diverse, including direct antagonism as well as bacterial stimulation of host defense mechanisms. In this work, we will review the current knowledge of the development of the intestinal bacterial and fungal community, the influence of the microbiota on human health and disease, and the role of the opportunistic yeast C. albicans. We will furthermore discuss the possible benefits of commensal fungal colonization. Finally, we will summarize the recent findings on bacterial-fungal interactions.},
}
@article {pmid29131106,
year = {2018},
author = {Heiss, CN and Olofsson, LE},
title = {Gut Microbiota-Dependent Modulation of Energy Metabolism.},
journal = {Journal of innate immunity},
volume = {10},
number = {3},
pages = {163-171},
doi = {10.1159/000481519},
pmid = {29131106},
issn = {1662-8128},
mesh = {Animals ; *Energy Metabolism ; Gastrointestinal Microbiome/*physiology ; Humans ; Hypothalamus/metabolism/physiology ; Leptin/metabolism ; Obesity/*metabolism/*microbiology ; Signal Transduction ; Symbiosis ; },
abstract = {The gut microbiota has emerged as an environmental factor that modulates the host's energy balance. It increases the host's ability to harvest energy from the digested food, and produces metabolites and microbial products such as short-chain fatty acids, secondary bile acids, and lipopolysaccharides. These metabolites and microbial products act as signaling molecules that modulate appetite, gut motility, energy uptake and storage, and energy expenditure. Several findings suggest that the gut microbiota can affect the development of obesity. Germ-free mice are leaner than conventionally raised mice and they are protected against diet-induced obesity. Furthermore, obese humans and rodents have an altered gut microbiota composition with less phylogeneic diversity compared to lean controls, and transplantation of the gut microbiota from obese subjects to germ-free mice can transfer the obese phenotype. Taken together, these findings indicate a role for the gut microbiota in obesity and suggest that the gut microbiota could be targeted to improve metabolic diseases like obesity. This review focuses on the role of the gut microbiota in energy balance regulation and its potential role in obesity.},
}
@article {pmid31493718,
year = {2019},
author = {Hidalgo-Castellanos, J and Duque, AS and Burgueño, A and Herrera-Cervera, JA and Fevereiro, P and López-Gómez, M},
title = {Overexpression of the arginine decarboxylase gene promotes the symbiotic interaction Medicago truncatula-Sinorhizobium meliloti and induces the accumulation of proline and spermine in nodules under salt stress conditions.},
journal = {Journal of plant physiology},
volume = {241},
number = {},
pages = {153034},
doi = {10.1016/j.jplph.2019.153034},
pmid = {31493718},
issn = {1618-1328},
abstract = {Legumes have the capacity to fix nitrogen in symbiosis with soil bacteria known as rhizobia by the formation of root nodules. However, nitrogen fixation is highly sensitive to soil salinity with a concomitant reduction of the plant yield and soil fertilization. Polycationic aliphatic amines known as polyamines (PAs) have been shown to be involved in the response to a variety of stresses in plants including soil salinity. Therefore, the generation of transgenic plants overexpressing genes involved in PA biosynthesis have been proposed as a promising tool to improve salt stress tolerance in plants. In this work we tested whether the modulation of PAs in transgenic Medicago truncatula plants was advantageous for the symbiotic interaction with Sinorhizobium meliloti under salt stress conditions, when compared to wild type plants. Consequently, we characterized the symbiotic response to salt stress of the homozygous M. truncatula plant line L-108, constitutively expressing the oat adc gene, coding for the PA biosynthetic enzyme arginine decarboxylase, involved in PAs biosynthesis. In a nodulation kinetic assay, nodule number incremented in L-108 plants under salt stress. In addition, these plants at vegetative stage showed higher nitrogenase and nodule biomass and, under salt stress, accumulated proline (Pro) and spermine (Spm) in nodules, while in wt plants, the accumulation of glutamic acid (Glu), γ-amino butyric acid (GABA) and 1-aminocyclopropane carboxylic acid (ACC) (the ethylene (ET) precursor) were the metabolites involved in the salt stress response. Therefore, overexpression of oat adc gene favours the symbiotic interaction between plants of M. truncatula L-108 and S. meliloti under salt stress and the accumulation of Pro and Spm, seems to be the molecules involved in salt stress tolerance.},
}
@article {pmid31492935,
year = {2019},
author = {Chagas, PMB and Caetano, AA and Tireli, AA and Cesar, PHS and Corrêa, AD and Guimarães, IDR},
title = {Use of an Environmental Pollutant From Hexavalent Chromium Removal as a Green Catalyst in The Fenton Process.},
journal = {Scientific reports},
volume = {9},
number = {1},
pages = {12819},
doi = {10.1038/s41598-019-49196-9},
pmid = {31492935},
issn = {2045-2322},
abstract = {The present study refers to the use of an environmental pollutant generated during the removal of hexavalent chromium from aqueous media. This pollutant is a material with catalytic properties suitable for application in the oxidative degradation of problematic organic compounds. The material, initially used as an adsorbent, is a composite prepared by modifying the crystalline phases of iron oxides together with the chitosan (CT-FeCr). Chemical and morphological characterizations of the materials were performed using SEM analysis coupled with EDS, XRD and DSC. The CT-FeCr beads were used in the degradation of methylene blue dye (MB) and showed excellent degradation potential (93.6%). The presence of Cr on the surface of the catalyst was responsible for the increase in catalytic activity compared to the CT-Fe and pure magnetite materials. The product of the effluent treatment and the presence of the catalyst itself in the environment do not pose toxic effects. In addition, the CT-FeCr beads showed catalytic stability for several consecutive reaction cycles with possible technical and economic viability. The concept of &quot;industrial symbiosis&quot; may be applied to this technology, with that term relating to the reuse of a byproduct generated in one particular industrial sector by another as a raw material.},
}
@article {pmid31492817,
year = {2019},
author = {Treitli, SC and Kolisko, M and Husník, F and Keeling, PJ and Hampl, V},
title = {Revealing the metabolic capacity of Streblomastix strix and its bacterial symbionts using single-cell metagenomics.},
journal = {Proceedings of the National Academy of Sciences of the United States of America},
volume = {},
number = {},
pages = {},
doi = {10.1073/pnas.1910793116},
pmid = {31492817},
issn = {1091-6490},
abstract = {Lower termites harbor in their hindgut complex microbial communities that are involved in the digestion of cellulose. Among these are protists, which are usually associated with specific bacterial symbionts found on their surface or inside their cells. While these form the foundations of a classic system in symbiosis research, we still know little about the functional basis for most of these relationships. Here, we describe the complex functional relationship between one protist, the oxymonad Streblomastix strix, and its ectosymbiotic bacterial community using single-cell genomics. We generated partial assemblies of the host S. strix genome and Candidatus Ordinivivax streblomastigis, as well as a complex metagenome assembly of at least 8 other Bacteroidetes bacteria confirmed by ribosomal (r)RNA fluorescence in situ hybridization (FISH) to be associated with S. strix. Our data suggest that S. strix is probably not involved in the cellulose digestion, but the bacterial community on its surface secretes a complex array of glycosyl hydrolases, providing them with the ability to degrade cellulose to monomers and fueling the metabolism of S. strix In addition, some of the bacteria can fix nitrogen and can theoretically provide S. strix with essential amino acids and cofactors, which the protist cannot synthesize. On the contrary, most of the bacterial symbionts lack the essential glycolytic enzyme enolase, which may be overcome by the exchange of intermediates with S. strix This study demonstrates the value of the combined single-cell (meta)genomic and FISH approach for studies of complicated symbiotic systems.},
}
@article {pmid31492669,
year = {2019},
author = {Zhou, K and Zhang, R and Sun, J and Zhang, W and Tian, RM and Chen, C and Kawagucci, S and Xu, Y},
title = {Potential SUP05-Phage Interactions in Hydrothermal Vent Sponges.},
journal = {Applied and environmental microbiology},
volume = {},
number = {},
pages = {},
doi = {10.1128/AEM.00992-19},
pmid = {31492669},
issn = {1098-5336},
abstract = {In deep-sea hydrothermal vent environments, sulfur-oxidizing bacteria belonging to the clade SUP05 are crucial symbionts of invertebrate animals. Marine viruses, as the most abundant biological entities in the ocean, play essential roles in regulating the sulfur metabolism of the SUP05 bacteria. To date, vent-sponge-associated SUP05 and their phages have not been well documented. The current study analyzed the microbiome of Haplosclerida spp. sponges from hydrothermal vents in the Okinawa Trough and recovered the dominant SUP05 genome, designated VS-SUP05. Phylogenetic analysis showed that VS-SUP05 was closely related to endosymbiotic SUP05 strains from mussels living in deep-sea hydrothermal vent fields. Homology and metabolic pathway comparisons against free-living and symbiotic SUP05 revealed that the VS-SUP05 genome shared many features with the deep-sea mussel symbionts. Supporting a potentially-symbiotic lifestyle, the VS-SUP05 genome contained genes involved in the synthesis of essential amino acids and cofactors that are desired by the host. Analysis of sponge-associated viral sequences revealed putative VS-SUP05 phages, all of which were double-stranded viruses belonging to the families Myoviridae, Siphoviridae, Podoviridae, and Microviridae Among the phage sequences, one contig contained metabolic genes (iscR, iscS, and iscU) involved in iron-sulfur cluster formation. Interestingly, genome sequence comparison revealed horizontal transfer of the iscS gene among phages, VS-SUP05 and other symbiotic SUP05, indicating an interaction between marine phages and SUP05 symbionts. Overall, our findings confirm the presence of SUP05 bacteria and their phages in sponges from deep-sea vents, and imply a beneficial interaction that allows adaptation of the host sponge to the hydrothermal vent environment.Importance Chemosynthetic SUP05 bacteria dominate the microbial communities of deep-sea hydrothermal vents around the world,. SUP05 bacteria utilize the reduced chemical compounds in vent fluids and commonly form symbioses with invertebrate organisms. This symbiotic relationship could be key to adapting to such unique and extreme environments. Viruses are the most abundant biological entities on the planet and have been identified in hydrothermal vent environments. However, their interactions with the symbiotic microbes of the SUP05 clade, along with their role in the symbiotic system, remain unclear. Here, using metagenomic sequence-based analyses, we determined that bacteriophages may support metabolism in SUP05 bacteria and play a role in the sponge-associated symbiosis system in hydrothermal vent environments.},
}
@article {pmid31492667,
year = {2019},
author = {Eckstein, S and Dominelli, N and Brachmann, A and Heermann, R},
title = {Phenotypic heterogeneity of insect pathogenic Photorhabdus luminescens - insights into the fate of secondary cells.},
journal = {Applied and environmental microbiology},
volume = {},
number = {},
pages = {},
doi = {10.1128/AEM.01910-19},
pmid = {31492667},
issn = {1098-5336},
abstract = {Photorhabdus luminescens are Gram-negative bacteria that live in symbiosis with soil nematodes and are simultaneously highly pathogenic towards insects. The bacteria exist in two phenotypically different forms, designated as primary (1°) and secondary (2°) cells. Yet unknown environmental stimuli as well as global stress conditions induce phenotypic switching of up to 50% of 1° to 2° cells. An important difference between the two phenotypic forms is that 2° cells are unable to live in symbiosis with nematodes and are therefore believed to remain in the soil after a successful infection cycle. In this work, we performed a transcriptomic analysis to highlight and better understand the role of 2° cells and their putative ability to adapt to a life in soil. We could confirm that the major phenotypic differences between the two cell forms are mediated at transcriptional level as the corresponding genes were down-regulated in 2° cells. Furthermore, 2° cells seem to be adapted to another environment as we found several differentially expressed genes involved in the cells' metabolism, motility and chemotaxis as well as stress resistance, which are either up- or down-regulated in 2° cells. As in contrast to 1° cells 2° cells chemotactically responded to different attractants including plant root exudates there is evidence for the rhizosphere as an alternative environment for the 2° cells. Since P. luminescens is biotechnologically used as bio-insecticide, investigation of a putative interaction of 2° cells with plants is also of great interest for agriculture.Importance The biological function and the fate of P. luminescens 2° cells was unclear. Here we performed comparative transcriptomics of P. luminescens 1° and 2° cultures and found several genes that are up- or down-regulated in 2° cells compared to 1° cells not only coding for known phenotypic differences of the two cell forms. Our results suggest that when 1° cells convert to 2° cells, they drastically change their way of life. Thus, 2° cells could easily adapt to an alternative environment such as a free live in the rhizosphere putatively utilizing plant derived compounds as nutrient source. Since 2° cells are not able to re-associate with the nematodes, an alternative lifestyle in the rhizosphere would be conceivable.},
}
@article {pmid31489370,
year = {2019},
author = {Sakanaka, M and Hansen, ME and Gotoh, A and Katoh, T and Yoshida, K and Odamaki, T and Yachi, H and Sugiyama, Y and Kurihara, S and Hirose, J and Urashima, T and Xiao, JZ and Kitaoka, M and Fukiya, S and Yokota, A and Lo Leggio, L and Abou Hachem, M and Katayama, T},
title = {Evolutionary adaptation in fucosyllactose uptake systems supports bifidobacteria-infant symbiosis.},
journal = {Science advances},
volume = {5},
number = {8},
pages = {eaaw7696},
doi = {10.1126/sciadv.aaw7696},
pmid = {31489370},
issn = {2375-2548},
abstract = {The human gut microbiota established during infancy has persistent effects on health. In vitro studies have suggested that human milk oligosaccharides (HMOs) in breast milk promote the formation of a bifidobacteria-rich microbiota in infant guts; however, the underlying molecular mechanism remains elusive. Here, we characterized two functionally distinct but overlapping fucosyllactose transporters (FL transporter-1 and -2) from Bifidobacterium longum subspecies infantis. Fecal DNA and HMO consumption analyses, combined with deposited metagenome data mining, revealed that FL transporter-2 is primarily associated with the bifidobacteria-rich microbiota formation in breast-fed infant guts. Structural analyses of the solute-binding protein (SBP) of FL transporter-2 complexed with 2'-fucosyllactose and 3-fucosyllactose, together with phylogenetic analysis of SBP homologs of both FL transporters, highlight a unique adaptation strategy of Bifidobacterium to HMOs, in which the gain-of-function mutations enable FL transporter-2 to efficiently capture major fucosylated HMOs. Our results provide a molecular insight into HMO-mediated symbiosis and coevolution between bifidobacteria and humans.},
}
@article {pmid30249322,
year = {2018},
author = {Chen, PW and Lin, YL and Huang, MS},
title = {Profiles of commensal and opportunistic bacteria in human milk from healthy donors in Taiwan.},
journal = {Journal of food and drug analysis},
volume = {26},
number = {4},
pages = {1235-1244},
doi = {10.1016/j.jfda.2018.03.004},
pmid = {30249322},
issn = {1021-9498},
mesh = {Adolescent ; Adult ; Bacteria/classification/genetics/*isolation &amp; purification ; Female ; Humans ; *Microbiota ; Milk, Human/chemistry/*microbiology ; Phylogeny ; Symbiosis ; Taiwan ; Young Adult ; },
abstract = {Recent studies indicate that milk from healthy mothers may harbor potential probiotics. Nonetheless, the distribution of bacterial profiles in human milk samples in Taiwan is not fully understood. Therefore, with the aim to address this question, in this study, milk samples were collected from 33 healthy mothers (D1 to D33) visiting our hospital during a 6-month period. The milk microbiota was analyzed by a molecular approach (Illumina MiSeq sequencing). The results indicate that the milk samples have a unique profile and patterns of bacterial abundance levels. Moreover, in colostrum and transitional-milk samples, we detected 154 and 127 bacterial species, respectively, and these sets shared 42.6% of the bacterial species. The most common bacterial species among all milk samples were Staphylococcus epidermidis, Streptococcus lactarius, and Staphylococcus hominis, suggesting that the skin contamination route plays an important role in the composition of the milk microbiota. Nevertheless, four Lactobacillus species, Lactobacillus helveticus, Lactobacillus iners, Lactobacillus zeae, and Lactobacillus gasseri, were present in only 7 samples (21% prevalence), and bifidobacterial species were quite rare taxa among the present samples. The Staphylococcus aureus was detected in a total of 15 samples (45% prevalence), suggesting that this species may be commonly present in milk samples. In conclusion, each milk sample revealed a unique profile and patterns of bacterial abundance levels, and our data do not support the idea that lactobacilli and bifidobacteria are common and abundant in modern milk samples. Because none of the donors of the milk samples showed mastitis or any discomfort during the sampling process or at follow-up inspection, the microbiota of these milk samples is not likely to negatively affect its host. This study provides new information on the proportions of commensal bacteria in human milk in Taiwan.},
}
@article {pmid30165400,
year = {2018},
author = {Gavelis, GS and Gile, GH},
title = {How did cyanobacteria first embark on the path to becoming plastids?: lessons from protist symbioses.},
journal = {FEMS microbiology letters},
volume = {365},
number = {19},
pages = {},
doi = {10.1093/femsle/fny209},
pmid = {30165400},
issn = {1574-6968},
mesh = {*Biological Evolution ; Cyanobacteria/genetics/*physiology ; Directed Molecular Evolution ; Eukaryota/genetics/*physiology ; Genetic Engineering ; Humans ; Photosynthesis ; Plastids/*physiology ; *Symbiosis ; },
abstract = {Symbioses between phototrophs and heterotrophs (a.k.a 'photosymbioses') are extremely common, and range from loose and temporary associations to obligate and highly specialized forms. In the history of life, the most transformative was the 'primary endosymbiosis,' wherein a cyanobacterium was engulfed by a eukaryote and became genetically integrated as a heritable photosynthetic organelle, or plastid. By allowing the rise of algae and plants, this event dramatically altered the biosphere, but its remote origin over one billion years ago has obscured the sequence of events leading to its establishment. Here, we review the genetic, physiological and developmental hurdles involved in early primary endosymbiosis. Since we cannot travel back in time to witness these evolutionary junctures, we will draw on examples of unicellular eukaryotes (protists) spanning diverse modes of photosymbiosis. We also review experimental approaches that could be used to recreate aspects of early primary endosymbiosis on a human timescale.},
}
@article {pmid31485773,
year = {2019},
author = {Feng, Z and Zhang, L and Wu, Y and Wang, L and Xu, M and Yang, M and Li, Y and Wei, G and Chou, M},
title = {The Rpf84 gene, encoding a ribosomal large subunit protein, RPL22, regulates symbiotic nodulation in Robinia pseudoacacia.},
journal = {Planta},
volume = {},
number = {},
pages = {},
doi = {10.1007/s00425-019-03267-3},
pmid = {31485773},
issn = {1432-2048},
support = {2016YFD0800706//National Key Research and Development Program of China/ ; 31172252//National Natural Science Foundation of China (CN)/ ; 2016JM3004//Natural Science Foundation of Shaanxi Province/ ; },
abstract = {MAIN CONCLUSION: A homologue of the ribosomal protein L22e, Rpf84, regulates root nodule symbiosis by mediating the infection process of rhizobia and preventing bacteroids from degradation in Robinia pseudoacacia. Ribosomal proteins (RPs) are known to have extraribosomal functions, including developmental regulation and stress responses; however, the effects of RPs on symbiotic nodulation of legumes are still unclear. Ribosomal protein 22 of the large 60S subunit (RPL22), a non-typical RP that is only found in eukaryotes, has been shown to function as a tumour suppressor in animals. Here, a homologue of RPL22, Rpf84, was identified from the leguminous tree R. pseudoacacia. Subcellular localization assays showed that Rpf84 was expressed in the cytoplasm and nucleus. Knockdown of Rpf84 by RNA interference (RNAi) technology impaired the infection process and nodule development. Compared with the control, root and stem length, dry weight and nodule number per plant were drastically decreased in Rpf84-RNAi plants. The numbers of root hair curlings, infection threads and nodule primordia were also significantly reduced. Ultrastructure analyses showed that Rpf84-RNAi nodules contained fewer infected cells with fewer bacteria. In particular, remarkable deformation of bacteroids and fusion of multiple symbiosomes occurred in infected cells. By contrast, overexpression of Rpf84 promoted nodulation, and the overexpression nodules maintained a larger infection/differentiation region and had more infected cells filled with bacteroids than the control at 45 days post inoculation, suggesting a retarded ageing process in nodules. These results indicate for the first time that RP regulates the symbiotic nodulation of legumes and that RPL22 may function in initiating the invasion of rhizobia and preventing bacteroids from degradation in R. pseudoacacia.},
}
@article {pmid31484206,
year = {2019},
author = {Huang, R and Li, Z and Mao, C and Zhang, H and Sun, Z and Li, H and Huang, C and Feng, Y and Shen, X and Bucher, M and Zhang, Z and Lin, Y and Cao, Y and Duanmu, D},
title = {Natural variation at OsCERK1 regulates arbuscular mycorrhizal symbiosis in rice.},
journal = {The New phytologist},
volume = {},
number = {},
pages = {},
doi = {10.1111/nph.16158},
pmid = {31484206},
issn = {1469-8137},
abstract = {The symbiotic interaction between arbuscular mycorrhizal fungi (AMF) and land plants is essential for efficient nutrient acquisition and utilization. Our understanding of key processes controlling the AMF colonization in rice is still limited. Dongxiang wild rice (DY) exhibited a stronger colonization with Rhizophagus irregularis than the rice cultivar Zhongzao 35 (ZZ35). Chromosome-segment substitution lines were constructed and the OsCERK1 gene from DY was mapped. Transgenic plants in the japonica rice Zhonghua 11 (ZZ11) were constructed to compare root colonization by AMF. Chromosome single-segment substitution lines containing OsCERK1DY showed higher phosphorus content and grain yield relative to ZZ35. Four amino acids substitutions were identified among the OsCERK1 haplotypes of DY, ZZ35 and ZH11, and two of them were in the second lysin motif domain, which is essential for the differences of AMF colonization level among rice varieties. Heterologous expression of OsCERK1DY in ZH11 significantly enhanced AMF colonization and increased resistance against the pathogenic fungi Magnaporthe oryzae. Notably, the OsCERK1DY haplotype was absent from 4,660 cultivated rice varieties. We conclude that OsCERK1 is a key gene affecting the symbiotic interaction with AMF and OsCERK1DY has the biotechnological potential to increase rice phosphorus acquisition and utilization efficiency for sustainable agriculture. This article is protected by copyright. All rights reserved.},
}
@article {pmid31479939,
year = {2019},
author = {Li, J and Wang, T and Yu, S and Bai, J and Qin, S},
title = {Community characteristics and ecological roles of bacterial biofilms associated with various algal settlements on coastal reefs.},
journal = {Journal of environmental management},
volume = {250},
number = {},
pages = {109459},
doi = {10.1016/j.jenvman.2019.109459},
pmid = {31479939},
issn = {1095-8630},
abstract = {Bacterial biofilms, which are a group of bacteria attaching to and ultimately forming communities on reefs, perform essential ecological functions in coastal ecosystems. Particularly, they may attract or repulse the settling down of opportunistic algae. However, this phenomenon and the interaction mechanism are not fully understood. This study investigated reefs from the Changdao coastal zone to determine the structures and functions of bacterial biofilms symbiosing with various algae using high-throughput sequencing analysis. The Shannon diversity index of microbiota with algal symbiosis reached 5.34, which was higher than that of microbiota wherein algae were absent (4.80). The beta diversity results for 11 samples revealed that there existed a separation between bacterial communities on reefs with and without attached algae, while communities with similar algae clustered together. The taxa mostly associated with algae-symbiotic microbiota are the Actinobacteria phylum, and the Flavobacteriia and Gammaproteobacteria classes. The Cyanobacteria phylum was not associated with algae-symbiotic microbiota. As revealed by functional analysis, the bacteria mostly involved in the metabolism of sulfur were represented by brown and red algae in the biofilm symbiosis. Bacteria related to the metabolism of certain trace elements were observed only in specific groups. Moreover, phototrophy-related bacteria were less abundant in samples coexisting with algae. This study established the link between bacterial biofilms and algal settlements on costal reefs, and revealed the possible holobiont relationship between them. This may provide new technical directions toward realizing algal cultivation and management during the construction of artificial reef ecosystems.},
}
@article {pmid31479095,
year = {2019},
author = {Azevedo, GPR and Paz, PHCD and Mattsson, HK and Moreira, APB and Leomil, L and Calegário, G and Appolinario, L and Vidal, L and Silva, BS and Tonon, LAC and Tschoeke, DA and Garcia, GD and Thompson, FL and Thompson, CC},
title = {[PROVISIONAL] Genome sequence of Shewanella corallii strain A687 isolated from pufferfish (Sphoeroides spengleri).},
journal = {Genetics and molecular biology},
volume = {},
number = {},
pages = {},
doi = {10.1590/1678-4685-GMB-2018-0314},
pmid = {31479095},
issn = {1415-4757},
abstract = {We present here the genome sequence of Shewanella corallii strain A687 isolated from pufferfish Sphoeroides spengleri (Family Tetraodontidae). The assembly consists of 5,215,037 bp and contains 284 contigs, with a G+C content of 50.3%. The genus Shewanella comprises 67 recognized species. These bacteria are Gram-negative, rod-shaped, facultatively anaerobic gammaproteobacteria and frequently isolated from marine environments (MacDonell &amp; Colwell, 1985, Sugimoto et al., 2018). Shewanella species are involved in the production of antimicrobial metabolites and tetrodotoxin, a strong neurotoxin (Simidu et al., 1990, Magarlamov et al., 2017, Matsui et al., 1989). Shewanella corallii was recorded from red sea coral (Shnit-Orland, 2010). The aim of the present study was to determine the genome sequence of Shewanella corallii strain A687. S. corallii A687 was isolated from pufferfish Sphoeroides spengleri (Family Tetraodontidae), in Arraial do Cabo (Brazil) in 2016. Genomic DNA was extracted using according to Pitcher's protocol (Pitcher et al., 1989) and used for 300-bp paired-end library preparation with Nextera XT DNA Sample Preparation Kit. The genome was sequenced using MiSeq (Illumina, San Diego, CA, USA) as previously described (Walter et al., 2016). Sequences obtained were pre-processed using PRINSEQ software to remove reads smaller than 35 bp and low-score sequences (Phred 30) (Schmieder &amp; Edwards, 2011). Sequence reads were assembled using A5-Miseq (Coil et al., 2015) and CAP3 software (Huang &amp; Madan, 1999). The gene prediction and functional annotation were performed using the RAST server (Overbeek et al., 2014). Secondary metabolism was analyzed by antiSMASH (Weber et al., 2015) and clustered regularly interspaced short palindromic repeat (CRISPR) arrays were determined with CRISPRFinder (Grissa et al., 2007). The sequencing generated a total of 4,557,272 reads and 768,079,097 bp that were assembled in 284 contigs (N50=298,540 bp). The estimated genome size is 5,215,037 bp with G+C of 50.3%, and a coverage of 146-fold. RAST predicted 4,555 coding sequences, and 175 RNA sequences (147 tRNAs, 11 16S rRNAs, 6 23S rRNAs, and 11 5S rRNAs). Analyzing the genes predicted by RAST, a total of 74 genes were involved in resistance to antibiotics and toxic compounds including copper homeostasis (N=8); bile hydrolysis (N=2); cobalt-zinc-cadmium resistance (N=20); resistance to fluoroquinolones (N=4); arsenic resistance (N=4); copper homeostasis: copper tolerance (N=6); tetracycline resistance, ribosome protection type II (N=2); beta-lactamase (N=5); multidrug resistance efflux pumps (N=22); resistance to chromium compounds (N=1); 24 genes for the metabolism of aromatic compounds, including salicylate ester, chloroaromatic and quinate degradation. Phage elements sequences (N=44) were found in this genome, and CRISPRs arrays candidates were predicted in four sequences. We searched through subsystems for genes associated to symbiosis. Genes encoding type I, (lapBCDE, lapL, lapP, RTX and TolC) and type II (TadA, TadB, TadC, VirB11, RcpC, CpaB and CpaF) secretion systems were detected. We also identified 16 genes related to vitamin B12 synthesis and four LuxR gene families (Bondarev et al., 2013).},
}
@article {pmid31478269,
year = {2019},
author = {Breusing, C and Johnson, SB and Vrijenhoek, RC and Young, CR},
title = {Host hybridization as a potential mechanism of lateral symbiont transfer in deep-sea vesicomyid clams.},
journal = {Molecular ecology},
volume = {},
number = {},
pages = {},
doi = {10.1111/mec.15224},
pmid = {31478269},
issn = {1365-294X},
abstract = {Deep-sea vesicomyid clams live in mutualistic symbiosis with chemosynthetic bacteria that are inherited through the maternal germ line. On evolutionary timescales, strictly vertical transmission should lead to co-speciation of host mitochondrial and symbiont lineages; nonetheless, examples of incongruent phylogenies have been reported, suggesting that symbionts are occasionally horizontally transmitted between host species. The current paradigm for vesicomyid clams holds that direct transfers cause host shifts or mixtures of symbionts. An alternative hypothesis suggests that hybridization between host species might explain symbiont transfers. Two clam species, Archivesica gigas and Phreagena soyoae, frequently co-occur at deep-sea hydrocarbon seeps in the eastern Pacific Ocean. Although the two species typically host gammaproteobacterial symbiont lineages marked by divergent 16S rRNA phylotypes, we identified a number of clams with the A. gigas mitotype that hosted symbionts with the P. soyoae phylotype. Demographic inference models based on genome-wide SNP data and three Sanger sequenced gene markers provided evidence that A. gigas and P. soyoae hybridized in the past, supporting the hypothesis that hybridization might be a viable mechanism of inter-specific symbiont transfer. These findings provide new perspectives on the evolution of vertically transmitted symbionts and their hosts in deep-sea chemosynthetic environments. This article is protected by copyright. All rights reserved.},
}
@article {pmid31477892,
year = {2019},
author = {Müller, LM and Flokova, K and Schnabel, E and Sun, X and Fei, Z and Frugoli, J and Bouwmeester, HJ and Harrison, MJ},
title = {A CLE-SUNN module regulates strigolactone content and fungal colonization in arbuscular mycorrhiza.},
journal = {Nature plants},
volume = {},
number = {},
pages = {},
doi = {10.1038/s41477-019-0501-1},
pmid = {31477892},
issn = {2055-0278},
abstract = {During arbuscular mycorrhizal symbiosis, colonization of the root is modulated in response to the physiological status of the plant, with regulation occurring locally and systemically. Here, we identify differentially expressed genes encoding CLAVATA3/ESR-related (CLE) peptides that negatively regulate colonization levels by modulating root strigolactone content. CLE function requires a receptor-like kinase, SUNN; thus, a CLE-SUNN-strigolactone feedback loop is one avenue through which the plant modulates colonization levels.},
}
@article {pmid31477738,
year = {2019},
author = {Ibny, FYI and Jaiswal, SK and Mohammed, M and Dakora, FD},
title = {Symbiotic effectiveness and ecologically adaptive traits of native rhizobial symbionts of Bambara groundnut (Vigna subterranea L. Verdc.) in Africa and their relationship with phylogeny.},
journal = {Scientific reports},
volume = {9},
number = {1},
pages = {12666},
doi = {10.1038/s41598-019-48944-1},
pmid = {31477738},
issn = {2045-2322},
abstract = {Bambara groundnut (Vigna subterranea L. Verdc.) is an indigenous, drought-tolerant, underutilized African food legume, with the ability to fix atmospheric N2 in symbiosis with soil bacteria called rhizobia. The aim of this study was to assess the morpho-physiological, symbiotic and phylogenetic characteristics of rhizobia nodulating Bambara groundnut in Ghana, Mali and South Africa. The morpho-physiologically diverse isolates tested were also found to exhibit differences in functional efficiency and phylogenetic positions. Based on Enterobacterial Repetitive Intergenic Consensus (ERIC)-PCR banding patterns, the isolates were grouped into eight major clusters. The concentrations of Ca, Na and K in soils had a significant (p ≤ 0.01) effect on the distribution of rhizobia. Though many isolates were symbiotically very effective, the effectiveness index varied markedly (p ≤ 0.05) among them. Moreover, the isolates also exhibited tolerance to a wide range of NaCl (0.5-7%), streptomycin (50-500 µg.ml-1), and kanamycin (25-150 µg.ml-1) concentrations. Additionally, these isolates could produce 0.02 to 69.71 µg.ml-1 of indole-3-acetic acid (IAA) in tryptophan-supplemented medium, as well as solubilize tri-calcium phosphate. Phylogenetic analysis of these rhizobial isolates using 16S rRNA, atpD, glnII, gyrB, recA and symbiotic (nifH and nodC) gene sequences revealed distinct and novel evolutionary lineages related to the genus Bradyrhizobium, with some of them being very close to Bradyrhizobium vignae, B. kavangense, B. subterraneum, B. elkanii and B. pachyrhizi.},
}
@article {pmid31477173,
year = {2019},
author = {Attardo, GM and Abd-Alla, AMM and Acosta-Serrano, A and Allen, JE and Bateta, R and Benoit, JB and Bourtzis, K and Caers, J and Caljon, G and Christensen, MB and Farrow, DW and Friedrich, M and Hua-Van, A and Jennings, EC and Larkin, DM and Lawson, D and Lehane, MJ and Lenis, VP and Lowy-Gallego, E and Macharia, RW and Malacrida, AR and Marco, HG and Masiga, D and Maslen, GL and Matetovici, I and Meisel, RP and Meki, I and Michalkova, V and Miller, WJ and Minx, P and Mireji, PO and Ometto, L and Parker, AG and Rio, R and Rose, C and Rosendale, AJ and Rota-Stabelli, O and Savini, G and Schoofs, L and Scolari, F and Swain, MT and Takáč, P and Tomlinson, C and Tsiamis, G and Van Den Abbeele, J and Vigneron, A and Wang, J and Warren, WC and Waterhouse, RM and Weirauch, MT and Weiss, BL and Wilson, RK and Zhao, X and Aksoy, S},
title = {Comparative genomic analysis of six Glossina genomes, vectors of African trypanosomes.},
journal = {Genome biology},
volume = {20},
number = {1},
pages = {187},
doi = {10.1186/s13059-019-1768-2},
pmid = {31477173},
issn = {1474-760X},
support = {D43 TW007391/TW/FIC NIH HHS/United States ; U01AI115648/NH/NIH HHS/United States ; R01AI051584/NH/NIH HHS/United States ; R03TW008413/NH/NIH HHS/United States ; R03TW009444/NH/NIH HHS/United States ; R21AI109263//National Institute of Allergy and Infectious Diseases/International ; U54HG003079/HG/NHGRI NIH HHS/United States ; },
abstract = {BACKGROUND: Tsetse flies (Glossina sp.) are the vectors of human and animal trypanosomiasis throughout sub-Saharan Africa. Tsetse flies are distinguished from other Diptera by unique adaptations, including lactation and the birthing of live young (obligate viviparity), a vertebrate blood-specific diet by both sexes, and obligate bacterial symbiosis. This work describes the comparative analysis of six Glossina genomes representing three sub-genera: Morsitans (G. morsitans morsitans, G. pallidipes, G. austeni), Palpalis (G. palpalis, G. fuscipes), and Fusca (G. brevipalpis) which represent different habitats, host preferences, and vectorial capacity.<br><br>RESULTS: Genomic analyses validate established evolutionary relationships and sub-genera. Syntenic analysis of Glossina relative to Drosophila melanogaster shows reduced structural conservation across the sex-linked X chromosome. Sex-linked scaffolds show increased rates of female-specific gene expression and lower evolutionary rates relative to autosome associated genes. Tsetse-specific genes are enriched in protease, odorant-binding, and helicase activities. Lactation-associated genes are conserved across all Glossina species while male seminal proteins are rapidly evolving. Olfactory and gustatory genes are reduced across the genus relative to other insects. Vision-associated Rhodopsin genes show conservation of motion detection/tracking functions and variance in the Rhodopsin detecting colors in the blue wavelength ranges.<br><br>CONCLUSIONS: Expanded genomic discoveries reveal the genetics underlying Glossina biology and provide a rich body of knowledge for basic science and disease control. They also provide insight into the evolutionary biology underlying novel adaptations and are relevant to applied aspects of vector control such as trap design and discovery of novel pest and disease control strategies.},
}
@article {pmid31475981,
year = {2019},
author = {Wardhani, TAK and Roswanjaya, YP and Dupin, S and Li, H and Linders, S and Hartog, M and Geurts, R and van Zeijl, A},
title = {Transforming, Genome Editing and Phenotyping the Nitrogen-fixing Tropical Cannabaceae Tree Parasponia andersonii.},
journal = {Journal of visualized experiments : JoVE},
volume = {},
number = {150},
pages = {},
doi = {10.3791/59971},
pmid = {31475981},
issn = {1940-087X},
abstract = {Parasponia andersonii is a fast-growing tropical tree that belongs to the Cannabis family (Cannabaceae). Together with 4 additional species, it forms the only known non-legume lineage able to establish a nitrogen-fixing nodule symbiosis with rhizobium. Comparative studies between legumes and P. andersonii could provide valuable insight into the genetic networks underlying root nodule formation. To facilitate comparative studies, we recently sequenced the P. andersonii genome and established Agrobacterium tumefaciens-mediated stable transformation and CRISPR/Cas9-based genome editing. Here, we provide a detailed description of the transformation and genome editing procedures developed for P. andersonii. In addition, we describe procedures for the seed germination and characterization of symbiotic phenotypes. Using this protocol, stable transgenic mutant lines can be generated in a period of 2-3 months. Vegetative in vitro propagation of T0 transgenic lines allows phenotyping experiments to be initiated at 4 months after A. tumefaciens co-cultivation. Therefore, this protocol takes only marginally longer than the transient Agrobacterium rhizogenes-based root transformation method available for P. andersonii, though offers several clear advantages. Together, the procedures described here permit P. andersonii to be used as a research model for studies aimed at understanding symbiotic associations as well as potentially other aspects of the biology of this tropical tree.},
}
@article {pmid31475451,
year = {2019},
author = {Hu, Y and Linz, DM and Parker, ES and Schwab, DB and Casasa, S and Macagno, ALM and Moczek, AP},
title = {Developmental bias in horned dung beetles and its contributions to innovation, adaptation, and resilience.},
journal = {Evolution &amp; development},
volume = {},
number = {},
pages = {},
doi = {10.1111/ede.12310},
pmid = {31475451},
issn = {1525-142X},
support = {//National Science Foundation/ ; //John Templeton Foundation/ ; },
abstract = {Developmental processes transduce diverse influences during phenotype formation, thereby biasing and structuring amount and type of phenotypic variation available for evolutionary processes to act on. The causes, extent, and consequences of this bias are subject to significant debate. Here we explore the role of developmental bias in contributing to organisms' ability to innovate, to adapt to novel or stressful conditions, and to generate well integrated, resilient phenotypes in the face of perturbations. We focus our inquiry on one taxon, the horned dung beetle genus Onthophagus, and review the role developmental bias might play across several levels of biological organization: (a) gene regulatory networks that pattern specific body regions; (b) plastic developmental mechanisms that coordinate body wide responses to changing environments and; (c) developmental symbioses and niche construction that enable organisms to build teams and to actively modify their own selective environments. We posit that across all these levels developmental bias shapes the way living systems innovate, adapt, and withstand stress, in ways that can alternately limit, bias, or facilitate developmental evolution. We conclude that the structuring contribution of developmental bias in evolution deserves further study to better understand why and how developmental evolution unfolds the way it does.},
}
@article {pmid31474965,
year = {2019},
author = {Chang, ACG and Chen, T and Li, N and Duan, J},
title = {Perspectives on Endosymbiosis in Coralloid Roots: Association of Cycads and Cyanobacteria.},
journal = {Frontiers in microbiology},
volume = {10},
number = {},
pages = {1888},
doi = {10.3389/fmicb.2019.01888},
pmid = {31474965},
issn = {1664-302X},
abstract = {Past endosymbiotic events allowed photosynthetic organisms to flourish and evolve in terrestrial areas. The precursor of chloroplasts was an ancient photosynthetic cyanobacterium. Presently, cyanobacteria are still capable of establishing successful symbioses in a wide range of hosts. One particular host plant among the gymnosperms is cycads (Order Cycadales) in which a special type of root system, referred to as coralloid roots, develops to house symbiotic cyanobacteria. A number of studies have explained coralloid root formation and cyanobiont invasion but the questions on mechanisms of this host-microbe association remains vague. Most researches focus on diversity of symbionts in coralloid roots but equally important is to explore the underlying mechanisms of cycads-Nostoc symbiosis as well. Besides providing an overview of relevant areas presently known about this association and citing putative genes involved in cycad-cyanobacteria symbioses, this paper aims to identify the limitations that hamper attempts to get to the root of the matter and suggests future research directions that may prove useful.},
}
@article {pmid31474946,
year = {2019},
author = {Beinart, RA and Luo, C and Konstantinidis, KT and Stewart, FJ and Girguis, PR},
title = {The Bacterial Symbionts of Closely Related Hydrothermal Vent Snails With Distinct Geochemical Habitats Show Broad Similarity in Chemoautotrophic Gene Content.},
journal = {Frontiers in microbiology},
volume = {10},
number = {},
pages = {1818},
doi = {10.3389/fmicb.2019.01818},
pmid = {31474946},
issn = {1664-302X},
abstract = {Symbiosis has evolved between a diversity of invertebrate taxa and chemosynthetic bacterial lineages. At the broadest level, these symbioses share primary function: the bacterial symbionts use the energy harnessed from the oxidation of reduced chemicals to power the fixation of inorganic carbon and/or other nutrients, providing the bulk of host nutrition. However, it is unclear to what extent the ecological niche of the host species is influenced by differences in symbiont traits, particularly those involved in chemoautotrophic function and interaction with the geochemical environment. Hydrothermal vents in the Lau Basin (Tonga) are home to four morphologically and physiologically similar snail species from the sister genera Alviniconcha and Ifremeria. Here, we assembled nearly complete genomes from their symbionts to determine whether differences in chemoautotrophic capacity exist among these symbionts that could explain the observed distribution of these snail species into distinct geochemical habitats. Phylogenomic analyses confirmed that the symbionts have evolved from four distinct lineages in the classes γ-proteobacteria or Campylobacteria. The genomes differed with respect to genes related to motility, adhesion, secretion, and amino acid uptake or excretion, though were quite similar in chemoautotrophic function, with all four containing genes for carbon fixation, sulfur and hydrogen oxidation, and oxygen and nitrate respiration. This indicates that differences in the presence or absence of symbiont chemoautotrophic functions does not likely explain the observed geochemical habitat partitioning. Rather, differences in gene expression and regulation, biochemical differences among these chemoautotrophic pathways, and/or differences in host physiology could all influence the observed patterns of habitat partitioning.},
}
@article {pmid31474535,
year = {2019},
author = {Weber, PM and Moessel, F and Paredes, GF and Viehboeck, T and Vischer, NOE and Bulgheresi, S},
title = {A Bidimensional Segregation Mode Maintains Symbiont Chromosome Orientation toward Its Host.},
journal = {Current biology : CB},
volume = {},
number = {},
pages = {},
doi = {10.1016/j.cub.2019.07.064},
pmid = {31474535},
issn = {1879-0445},
abstract = {All living organisms require accurate segregation of their genetic material. However, in microbes, chromosome segregation is less understood than replication and cell division, which makes its decipherment a compelling research frontier. Furthermore, it has only been studied in free-living microbes so far. Here, we investigated this fundamental process in a rod-shaped symbiont, Candidatus Thiosymbion oneisti. This gammaproteobacterium divides longitudinally as to form a columnar epithelium ensheathing its nematode host. We hypothesized that uninterrupted host attachment would affect bacterial chromosome dynamics and set out to localize specific chromosomal loci and putative DNA-segregating proteins by fluorescence in situ hybridization and immunostaining, respectively. First, DNA replication origins (ori) number per cell demonstrated symbiont monoploidy. Second, we showed that sister ori segregate diagonally prior to septation onset. Moreover, the localization pattern of the centromere-binding protein ParB recapitulates that of ori, and consistently, we showed recombinant ParB to specifically bind an ori-proximal site (parS) in vitro. Third, chromosome replication ends prior to cell fission, and as the poles start to invaginate, termination of replication (ter) sites localize medially, at the leading edges of the growing septum. They then migrate to midcell, concomitantly with septation progression and until this is completed. In conclusion, we propose that symbiont ParB might drive chromosome segregation along the short axis and that tethering of sister ter regions to the growing septum mediates their migration along the long axis. Crucially, active bidimensional segregation of the chromosome allows transgenerational maintenance of its configuration, and therefore, it may represent an adaptation to symbiosis. VIDEO ABSTRACT.},
}
@article {pmid31471999,
year = {2019},
author = {Khemaissia, H and Jelassi, R and Ghemari, C and Raimond, M and Souty-Grosset, C and Nasri-Ammar, K},
title = {Evaluation of trace element contamination using Armadillo officinalis Duméril, 1816 (Crustacea, Isopoda) as a tool: An ultrastructural study.},
journal = {Microscopy research and technique},
volume = {},
number = {},
pages = {},
doi = {10.1002/jemt.23371},
pmid = {31471999},
issn = {1097-0029},
abstract = {To estimate trace element bioaccumulation in Armadillo officinalis, specimens were collected from Ghar El Melh lagoon then exposed for 3 weeks in contaminated sediments with copper, zinc, and cadmium. From the first week until the end of the experiment, a decrease in A. officinalis growth related to the increase of Cd concentration in the sediment was recorded. However, a mass gain was highlighted under Cu and Zn exposures. At the end of experiment, body metal concentrations were measured using flame atomic emission spectrometry. Results of the bioaccumulation factor showed that the species could be considered as a macroconcentrator of copper (BAF > 2) and a deconcentrator of zinc (BAF < 2). Microscopy observations of hepatopancreas cells showed morphological and histological changes even at the lowest concentration. They consisted in the microvillus border destruction, lipid droplets modifications, trace element accumulation, and the condensation of the majority of cellular organelles. The degree of these alterations was found to be dose-dependent. Through these results, the isopod A. officinalis could be used as relevant monitor organisms for soil metal contamination.},
}
@article {pmid31468195,
year = {2019},
author = {Cui, Y and Gao, J and He, Y and Jiang, L},
title = {Plant extracellular vesicles.},
journal = {Protoplasma},
volume = {},
number = {},
pages = {},
doi = {10.1007/s00709-019-01435-6},
pmid = {31468195},
issn = {1615-6102},
support = {AoE/M-05/12, CUHK14130716, 14102417, 14100818, 14104716, C4012-16E, C4002-17G, and RIF R4005-18//Chinese University of Hong Kong/ ; 31670179 and 91854201//National Natural Science Foundation of China/ ; },
abstract = {Exocytosis is a key mechanism for delivering materials into the extracellular space for cell function and communication. In plant cells, conventional protein secretion (CPS) is achieved via an ER (endoplasmic reticulum)-Golgi-TGN (trans-Golgi network)-PM (plasma membrane) pathway. Unconventional protein secretion (UPS) bypassing these secretory organelles is also in operation and can potentially lead to the formation of extracellular vesicles (EVs) in plant cells. Although multiple types of EVs have been identified and shown to play important roles in mediating intercellular communications in mammalian cells, there has been a long debate about the possible existence of EVs in plants because of the presence of the cell wall. However, increasing evidence suggests that plants also release EVs having various functions including unconventional protein secretion, RNA transport, and defense against pathogens. In this review, we present an update on the current knowledge about the nature, secretory mechanism, and function of various types of EVs in plants. The key regulators involved in EV secretion are also summarized and discussed. We pay special attention to the function of EVs in plant defense and symbiosis.},
}
@article {pmid31465455,
year = {2019},
author = {Tikhonenkov, DV and Jhin, SH and Eglit, Y and Miller, K and Plotnikov, A and Simpson, AGB and Park, JS},
title = {Ecological and evolutionary patterns in the enigmatic protist genus Percolomonas (Heterolobosea; Discoba) from diverse habitats.},
journal = {PloS one},
volume = {14},
number = {8},
pages = {e0216188},
doi = {10.1371/journal.pone.0216188},
pmid = {31465455},
issn = {1932-6203},
abstract = {The heterotrophic flagellate Percolomonas cosmopolitus (Heterolobosea) is often observed in saline habitats worldwide, from coastal waters to saturated brines. However, only two cultures assigned to this morphospecies have been examined using molecular methods, and their 18S rRNA gene sequences are extremely different. Further the salinity tolerances of individual strains are unknown. Thus, our knowledge on the autecology and diversity in this morphospecies is deficient. Here, we report 18S rRNA gene data on seven strains similar to P. cosmopolitus from seven geographically remote locations (New Zealand, Kenya, Korea, Poland, Russia, Spain, and the USA) with sample salinities ranging from 4‰ to 280‰, and compare morphology and salinity tolerance of the nine available strains. Percolomonas cosmopolitus-like strains show few-to-no consistent morphological differences, and form six clades separated by often extremely large 18S rRNA gene divergences (up to 42.4%). Some strains grow best at salinities from 75 to 125‰ and represent halophiles. All but one of these belong to two geographically heterogeneous clusters that form a robust monophyletic group in phylogenetic trees; this likely represents an ecologically specialized subclade of halophiles. Our results suggest that P. cosmopolitus is a cluster of several cryptic species (at least), which are unlikely to be distinguished by geography. Interestingly, the 9 Percolomonas strains formed a clade in 18S rRNA gene phylogenies, unlike most previous analyses based on two sequences.},
}
@article {pmid31464214,
year = {2019},
author = {Shah, S and Darekar, B and Salvi, S and Kowale, A},
title = {Quadriceps strength in patients with chronic obstructive pulmonary disease.},
journal = {Lung India : official organ of Indian Chest Society},
volume = {36},
number = {5},
pages = {417-421},
doi = {10.4103/lungindia.lungindia_27_19},
pmid = {31464214},
issn = {0970-2113},
abstract = {Background: Skeletal muscle dysfunction is well known in chronic obstructive pulmonary disease (COPD). The muscle strength is altered in various muscles variedly. Lower-limb muscle strength is very important for walking distance. Reduced lower-limb strength can affect the physical quality of life.<br><br>Objectives: The aim of the study was to assess and compare the quadriceps strength in COPD patients and age-matched healthy controls and to study the correlation between lung function parameters and the quadriceps strength in patients with COPD.<br><br>Methodology: Thirty nonsmoker male patients; thirty nonsmoker female patients with COPD; and sixty age-, BMI-, and gender-matched healthy controls were studied. Quadriceps muscle strength was measured using a quadriceps dynamometer. Forced vital capacity (FVC), forced expiratory volume in 1 s (FEV1), FEF 25-75, and peak expiratory flow rate were measured using Helios 702 Spirometer. The quadriceps muscle strength between the two groups was compared using the unpaired Student's t-test. Correlations between FVC and FEV1with muscle strength were analyzed using the Pearson's coefficient.<br><br>Results: The mean unilateral and bilateral quadriceps strength in both male and female COPD patients was significantly lesser than the healthy controls (P < 0.05). There was a significant positive correlation between muscle strength and FVC and muscle strength and FEV1in patients with COPD.<br><br>Conclusion: The study shows that there is quadriceps weakness in COPD patients, and pulmonary functions have a direct impact on skeletal muscle strength. Identifying those patients who have reduced strength will allow early interventions targeted at improving the quality of life of the patient.},
}
@article {pmid31463869,
year = {2019},
author = {Monteiro, PHR and Kaschuk, G and Winagraski, E and Auer, CG and Higa, AR},
title = {Rhizobial inoculation in black wattle plantation (Acacia mearnsii De Wild.) in production systems of southern Brazil.},
journal = {Brazilian journal of microbiology : [publication of the Brazilian Society for Microbiology]},
volume = {},
number = {},
pages = {},
doi = {10.1007/s42770-019-00148-5},
pmid = {31463869},
issn = {1678-4405},
abstract = {Black wattle (Acacia mearnsii De Wild.) is a tree legume native to southeast Australia, but present in all continents. Today it covers about 142,400 ha in Brazil, with plantations concentrated in the southern region of the country. Black wattle may form nodules and establish rhizobial symbiosis capable of fixing N2, but rhizobial inoculation is not done in commercial plantations. About 40 kg ha-1 of urea is applied during seedling transplantation. In this review, evidences by which rhizobial inoculation affects monoculture, mixed cultivation, and agroforestry black wattle production systems were searched in literature. Previous measurements in cultivated forests have indicated that biological nitrogen fixation in black wattle may provide up to 200 kg of N ha-1 year-1 to the soil. Therefore, rhizobia inoculation may bring several opportunities to improve black wattle production systems. Black wattle is not a very selective partner in the rhizobial symbiosis, but the genus Bradyrhizobium dominates the rhizobial diversity of black wattle nodules. Investigation on rhizobial diversity in soils where the crop is cultivated may represent an opportunity to find more effective rhizobia strains for inoculants. The successful history of biological nitrogen fixation in grain legumes must inspire the history of tree legumes. Microbiology applied to forestry must overcome challenges on the lack of trained professionals and the development of new application technologies.},
}
@article {pmid31463006,
year = {2019},
author = {Couret, J and Huynh-Griffin, L and Antolic-Soban, I and Acevedo-Gonzalez, TS and Gerardo, NM},
title = {Even obligate symbioses show signs of ecological contingency: Impacts of symbiosis for an invasive stinkbug are mediated by host plant context.},
journal = {Ecology and evolution},
volume = {9},
number = {16},
pages = {9087-9099},
doi = {10.1002/ece3.5454},
pmid = {31463006},
issn = {2045-7758},
abstract = {Abstract: Many species interactions are dependent on environmental context, yet the benefits of obligate, mutualistic microbial symbioses to their hosts are typically assumed to be universal across environments. We directly tested this assumption, focusing on the symbiosis between the sap-feeding insect Megacopta cribraria and its primary bacterial symbiont Candidatus Ishikawaella capsulata. We assessed host development time, survival, and body size in the presence and absence of the symbiont on two alternative host plants and in the insects' new invasive range. We found that association with the symbiont was critical for host survival to adulthood when reared on either host plant, with few individuals surviving in the absence of symbiosis. Developmental differences between hosts with and without microbial symbionts, however, were mediated by the host plants on which the insects were reared. Our results support the hypothesis that benefits associated with this host-microbe interaction are environmentally contingent, though given that few individuals survive to adulthood without their symbionts, this may have minimal impact on ecological dynamics and current evolutionary trajectories of these partners.<br><br>OPEN RESEARCH BADGES: This article has earned an Open Data Badge for making publicly available the digitally-shareable data necessary to reproduce the reported results. The data is available at https://doi.org/10.5061/dryad.kg4bc56.},
}
@article {pmid31461957,
year = {2019},
author = {Bahadur, A and Batool, A and Nasir, F and Jiang, S and Mingsen, Q and Zhang, Q and Pan, J and Liu, Y and Feng, H},
title = {Mechanistic Insights into Arbuscular Mycorrhizal Fungi-Mediated Drought Stress Tolerance in Plants.},
journal = {International journal of molecular sciences},
volume = {20},
number = {17},
pages = {},
doi = {10.3390/ijms20174199},
pmid = {31461957},
issn = {1422-0067},
support = {41430749//National Natural Science Foundation of China/ ; 31670433//National Natural Science Foundation of China/ ; 31470524//National Natural Science Foundation of China/ ; 31500427//National Natural Science Foundation of China/ ; 31570512//National Natural Science Foundation of China/ ; 2014 T70949//China Postdoctoral Science Foundation/ ; 2015 M582735//China Postdoctoral Science Foundation/ ; SKLFSE200901//State Key Laboratory of Frozen Soil Engineering/ ; },
abstract = {Arbuscular mycorrhizal fungi (AMF) establish symbiotic interaction with 80% of known land plants. It has a pronounced impact on plant growth, water absorption, mineral nutrition, and protection from abiotic stresses. Plants are very dynamic systems having great adaptability under continuously changing drying conditions. In this regard, the function of AMF as a biological tool for improving plant drought stress tolerance and phenotypic plasticity, in terms of establishing mutualistic associations, seems an innovative approach towards sustainable agriculture. However, a better understanding of these complex interconnected signaling pathways and AMF-mediated mechanisms that regulate the drought tolerance in plants will enhance its potential application as an innovative approach in environmentally friendly agriculture. This paper reviews the underlying mechanisms that are confidently linked with plant-AMF interaction in alleviating drought stress, constructing emphasis on phytohormones and signaling molecules and their interaction with biochemical, and physiological processes to maintain the homeostasis of nutrient and water cycling and plant growth performance. Likewise, the paper will analyze how the AMF symbiosis helps the plant to overcome the deleterious effects of stress is also evaluated. Finally, we review how interactions between various signaling mechanisms governed by AMF symbiosis modulate different physiological responses to improve drought tolerance. Understanding the AMF-mediated mechanisms that are important for regulating the establishment of the mycorrhizal association and the plant protective responses towards unfavorable conditions will open new approaches to exploit AMF as a bioprotective tool against drought.},
}
@article {pmid31456765,
year = {2019},
author = {Balestrini, R and Rosso, LC and Veronico, P and Melillo, MT and De Luca, F and Fanelli, E and Colagiero, M and di Fossalunga, AS and Ciancio, A and Pentimone, I},
title = {Transcriptomic Responses to Water Deficit and Nematode Infection in Mycorrhizal Tomato Roots.},
journal = {Frontiers in microbiology},
volume = {10},
number = {},
pages = {1807},
doi = {10.3389/fmicb.2019.01807},
pmid = {31456765},
issn = {1664-302X},
abstract = {Climate changes include the intensification of drought in many parts of the world, increasing its frequency, severity and duration. However, under natural conditions, environmental stresses do not occur alone, and, in addition, more stressed plants may become more susceptible to attacks by pests and pathogens. Studies on the impact of the arbuscular mycorrhizal (AM) symbiosis on tomato response to water deficit showed that several drought-responsive genes are differentially regulated in AM-colonized tomato plants (roots and leaves) during water deficit. To date, global changes in mycorrhizal tomato root transcripts under water stress conditions have not been yet investigated. Here, changes in root transcriptome in the presence of an AM fungus, with or without water stress (WS) application, have been evaluated in a commercial tomato cultivar already investigated for the water stress response during AM symbiosis. Since root-knot nematodes (RKNs, Meloidogyne incognita) are obligate endoparasites and cause severe yield losses in tomato, the impact of the AM fungal colonization on RKN infection at 7 days post-inoculation was also evaluated. Results offer new information about the response to AM symbiosis, highlighting a functional redundancy for several tomato gene families, as well as on the tomato and fungal genes involved in WS response during symbiosis, underlying the role of the AM fungus. Changes in the expression of tomato genes related to nematode infection during AM symbiosis highlight a role of AM colonization in triggering defense responses against RKN in tomato. Overall, new datasets on the tomato response to an abiotic and biotic stress during AM symbiosis have been obtained, providing useful data for further researches.},
}
@article {pmid31455640,
year = {2019},
author = {Creekmore, BC and Gray, JH and Walton, WG and Biernat, KA and Little, MS and Xu, Y and Liu, J and Gharaibeh, RZ and Redinbo, MR},
title = {Mouse Gut Microbiome-Encoded β-Glucuronidases Identified Using Metagenome Analysis Guided by Protein Structure.},
journal = {mSystems},
volume = {4},
number = {4},
pages = {},
doi = {10.1128/mSystems.00452-19},
pmid = {31455640},
issn = {2379-5077},
abstract = {Gut microbial β-glucuronidase (GUS) enzymes play important roles in drug efficacy and toxicity, intestinal carcinogenesis, and mammalian-microbial symbiosis. Recently, the first catalog of human gut GUS proteins was provided for the Human Microbiome Project stool sample database and revealed 279 unique GUS enzymes organized into six categories based on active-site structural features. Because mice represent a model biomedical research organism, here we provide an analogous catalog of mouse intestinal microbial GUS proteins-a mouse gut GUSome. Using metagenome analysis guided by protein structure, we examined 2.5 million unique proteins from a comprehensive mouse gut metagenome created from several mouse strains, providers, housing conditions, and diets. We identified 444 unique GUS proteins and organized them into six categories based on active-site features, similarly to the human GUSome analysis. GUS enzymes were encoded by the major gut microbial phyla, including Firmicutes (60%) and Bacteroidetes (21%), and there were nearly 20% for which taxonomy could not be assigned. No differences in gut microbial gus gene composition were observed for mice based on sex. However, mice exhibited gus differences based on active-site features associated with provider, location, strain, and diet. Furthermore, diet yielded the largest differences in gus composition. Biochemical analysis of two low-fat-associated GUS enzymes revealed that they are variable with respect to their efficacy of processing both sulfated and nonsulfated heparan nonasaccharides containing terminal glucuronides.IMPORTANCE Mice are commonly employed as model organisms of mammalian disease; as such, our understanding of the compositions of their gut microbiomes is critical to appreciating how the mouse and human gastrointestinal tracts mirror one another. GUS enzymes, with importance in normal physiology and disease, are an attractive set of proteins to use for such analyses. Here we show that while the specific GUS enzymes differ at the sequence level, a core GUSome functionality appears conserved between mouse and human gastrointestinal bacteria. Mouse strain, provider, housing location, and diet exhibit distinct GUSomes and gus gene compositions, but sex seems not to affect the GUSome. These data provide a basis for understanding the gut microbial GUS enzymes present in commonly used laboratory mice. Further, they demonstrate the utility of metagenome analysis guided by protein structure to provide specific sets of functionally related proteins from whole-genome metagenome sequencing data.},
}
@article {pmid31455638,
year = {2019},
author = {Lim, SJ and Alexander, L and Engel, AS and Paterson, AT and Anderson, LC and Campbell, BJ},
title = {Extensive Thioautotrophic Gill Endosymbiont Diversity within a Single Ctena orbiculata (Bivalvia: Lucinidae) Population and Implications for Defining Host-Symbiont Specificity and Species Recognition.},
journal = {mSystems},
volume = {4},
number = {4},
pages = {},
doi = {10.1128/mSystems.00280-19},
pmid = {31455638},
issn = {2379-5077},
abstract = {Seagrass-dwelling members of the bivalve family Lucinidae harbor environmentally acquired gill endosymbionts. According to previous studies, lucinid symbionts potentially represent multiple strains from a single thioautotrophic gammaproteobacterium species. This study utilized genomic- and transcriptomic-level data to resolve symbiont taxonomic, genetic, and functional diversity from Ctena orbiculata endosymbiont populations inhabiting carbonate-rich sediment at Sugarloaf Key, FL (USA). The sediment had mixed seagrass and calcareous green alga coverage and also was colonized by at least five other lucinid species. Four coexisting, thioautotrophic endosymbiont operational taxonomic units (OTUs), likely representing four strains from two different bacterial species, were identified from C. orbiculata Three of these OTUs also occurred at high relative abundances in the other sympatric lucinid species. Interspecies genetic differences averaged about 5% lower at both pairwise average nucleotide identity and amino acid identity than interstrain differences. Despite these genetic differences, C. orbiculata endosymbionts shared a high number of metabolic functions, including highly expressed thioautotrophy-related genes and a moderately to weakly expressed conserved one-carbon (C1) oxidation gene cluster previously undescribed in lucinid symbionts. Few symbiont- and host-related genes, including those encoding symbiotic sulfurtransferase, host respiratory functions, and host sulfide oxidation functions, were differentially expressed between seagrass- and alga-covered sediment locations. In contrast to previous studies, the identification of multiple endosymbiont taxa within and across C. orbiculata individuals, which were also shared with other sympatric lucinid species, suggests that neither host nor endosymbiont displays strict taxonomic specificity. This necessitates further investigations into the nature and extent of specificity of lucinid hosts and their symbionts.IMPORTANCE Symbiont diversity and host/symbiont functions have been comprehensively profiled for only a few lucinid species. In this work, unprecedented thioautotrophic gill endosymbiont taxonomic diversity was characterized within a Ctena orbiculata population associated with both seagrass- and alga-covered sediments. Endosymbiont metabolisms included known chemosynthetic functions and an additional conserved, previously uncharacterized C1 oxidation pathway. Lucinid-symbiont associations were not species specific because this C. orbiculata population hosted multiple endosymbiont strains and species, and other sympatric lucinid species shared overlapping symbiont 16S rRNA gene diversity profiles with C. orbiculata Our results suggest that lucinid-symbiont association patterns within some host species could be more taxonomically diverse than previously thought. As such, this study highlights the importance of holistic analyses, at the population, community, and even ecosystem levels, in understanding host-microbe association patterns.},
}
@article {pmid31450847,
year = {2019},
author = {Wang, F and Sun, Y and Shi, Z},
title = {Arbuscular Mycorrhiza Enhances Biomass Production and Salt Tolerance of Sweet Sorghum.},
journal = {Microorganisms},
volume = {7},
number = {9},
pages = {},
doi = {10.3390/microorganisms7090289},
pmid = {31450847},
issn = {2076-2607},
support = {41471395//National Natural Science Foundation of China/ ; 154100510010//Plan for Scientific Innovation Talent of Henan Province/ ; 0100229003//Doctoral Foundation of QUST/ ; Qian Jiao He KY Zi[2017]010//Education Department of Guizhou Province Key Laboratory of Soil Resources and Environment in Qianbei of Guizhou Province/ ; },
abstract = {Arbuscular mycorrhizal (AM) fungi (AMF) are widely known to form a symbiosis with most higher plants and enhance plant adaptation to a series of environmental stresses. Sweet sorghum (Sorghum bicolor (L.) Moench) is considered a promising alternative feedstock for bioalcohol production because of its sugar-rich stalk and high biomass. However, little is known of AMF benefit for biomass production and salt tolerance of sweet sorghum. Here, we investigated the effects of Acaulosporamellea ZZ on growth and salt tolerance in two sweet sorghum cultivars (Liaotian5 and Yajin2) under different NaCl addition levels (0, 0.5, 1, 2, and 3 g NaCl/kg soil). Results showed AMF colonized the two cultivars well under all NaCl addition levels. NaCl addition increased mycorrhizal colonization rates in Yajin2, but the effects on Liaotian5 ranged from stimulatory at 0.5 and 1 g/kg to insignificant at 2 g/kg, and even inhibitory at 3 g/kg. High NaCl addition levels produced negative effects on both AM and non-AM plants, leading to lower biomass production, poorer mineral nutrition (N, P, K), higher Na+ uptake, and lower soluble sugar content in leaves. Compared with non-AM plants, AM plants of both cultivars had improved plant biomass and mineral uptake, as well as higher K+/Na+ ratio, but only Yajin2 plants had a low shoot/root Na ratio. AM inoculation increased the activities of superoxide dismutase (SOD), peroxidase (POD), and catalase (CAT), and soluble sugar content in leaves. Overall, both cultivars benefited from mycorrhization, and Yajin2 with less salt tolerance showed higher mycorrhizal response. In conclusion, AMF could help to alleviate the negative effects caused by salinity, and thus showed potential in biomass production of sweet sorghum in saline soil.},
}
@article {pmid31450827,
year = {2019},
author = {Bi, Y and Wang, F and Zhang, W},
title = {Omics Analysis for Dinoflagellates Biology Research.},
journal = {Microorganisms},
volume = {7},
number = {9},
pages = {},
doi = {10.3390/microorganisms7090288},
pmid = {31450827},
issn = {2076-2607},
support = {2018YFA0903000 and 2018YFA0903600//National Key R&amp;D Program of China/ ; 31770100, 91751102, 21621004, 31370115 and 31470217//National Natural Science Foundation of China/ ; },
abstract = {Dinoflagellates are important primary producers for marine ecosystems and are also responsible for certain essential components in human foods. However, they are also notorious for their ability to form harmful algal blooms, and cause shellfish poisoning. Although much work has been devoted to dinoflagellates in recent decades, our understanding of them at a molecular level is still limited owing to some of their challenging biological properties, such as large genome size, permanently condensed liquid-crystalline chromosomes, and the 10-fold lower ratio of protein to DNA than other eukaryotic species. In recent years, omics technologies, such as genomics, transcriptomics, proteomics, and metabolomics, have been applied to the study of marine dinoflagellates and have uncovered many new physiological and metabolic characteristics of dinoflagellates. In this article, we review recent application of omics technologies in revealing some of the unusual features of dinoflagellate genomes and molecular mechanisms relevant to their biology, including the mechanism of harmful algal bloom formations, toxin biosynthesis, symbiosis, lipid biosynthesis, as well as species identification and evolution. We also discuss the challenges and provide prospective further study directions and applications of dinoflagellates.},
}
@article {pmid31450667,
year = {2019},
author = {Chakraborty, S and Nguyen, B and Wasti, SD and Xu, G},
title = {Plant Leucine-Rich Repeat Receptor Kinase (LRR-RK): Structure, Ligand Perception, and Activation Mechanism.},
journal = {Molecules (Basel, Switzerland)},
volume = {24},
number = {17},
pages = {},
doi = {10.3390/molecules24173081},
pmid = {31450667},
issn = {1420-3049},
abstract = {In recent years, secreted peptides have been recognized as essential mediators of intercellular communication which governs plant growth, development, environmental interactions, and other mediated biological responses, such as stem cell homeostasis, cell proliferation, wound healing, hormone sensation, immune defense, and symbiosis, among others. Many of the known secreted peptide ligand receptors belong to the leucine-rich repeat receptor kinase (LRR-RK) family of membrane integral receptors, which contain more than 200 members within Arabidopsis making it the largest family of plant receptor kinases (RKs). Genetic and biochemical studies have provided valuable data regarding peptide ligands and LRR-RKs, however, visualization of ligand/LRR-RK complex structures at the atomic level is vital to understand the functions of LRR-RKs and their mediated biological processes. The structures of many plant LRR-RK receptors in complex with corresponding ligands have been solved by X-ray crystallography, revealing new mechanisms of ligand-induced receptor kinase activation. In this review, we briefly elaborate the peptide ligands, and aim to detail the structures and mechanisms of LRR-RK activation as induced by secreted peptide ligands within plants.},
}
@article {pmid31450061,
year = {2019},
author = {Chen, X and Hu, Z and Qi, Y and Song, C and Chen, G},
title = {The interactions of algae-activated sludge symbiotic system and its effects on wastewater treatment and lipid accumulation.},
journal = {Bioresource technology},
volume = {292},
number = {},
pages = {122017},
doi = {10.1016/j.biortech.2019.122017},
pmid = {31450061},
issn = {1873-2976},
abstract = {The ability of Scenedesmus sp. 336, Chlorella sp. 1602 and activated sludge (AS) alone or in combination to remove nutrients and accumulate lipid in artificial municipal wastewater under light/dark conditions was studied. The symbiotic systems showed greater advantages than the sterile systems. Scenedesmus sp. 336 + AS system obtained the highest lipid productivity after seven days of cultivation in light, while the NO3--N and COD were completely absorbed and utilized, as well as the removal rate of PO43--P and NH4+-N were 99.82% and 87.13%, respectively. Total superoxide dismutase (SOD) activity was measured to demonstrate the relationship between oxidative stress and lipid accumulation. Besides, the results of microbial analysis showed that some dominant plant growth-promoting bacteria could secrete indole-3-acetic acid (IAA) to enhance the interaction between algae and bacteria, and the denitrifying bacteria that could coexist with microalgae also improved the efficiency of wastewater treatment in the symbiotic systems.},
}
@article {pmid31449853,
year = {2019},
author = {Dorchin, N and Harris, KM and Stireman Iii, JO},
title = {Phylogeny of the gall midges (Diptera, Cecidomyiidae, Cecidomyiinae): systematics, evolution of feeding modes and diversification rates.},
journal = {Molecular phylogenetics and evolution},
volume = {},
number = {},
pages = {106602},
doi = {10.1016/j.ympev.2019.106602},
pmid = {31449853},
issn = {1095-9513},
abstract = {Gall midges (Cecidomyiidae) constitute one of the largest and most diverse families of Diptera, with close to 6600 described species and thousands of undescribed species worldwide. The family is divided into six subfamilies, the five basal ones comprising only fungivorous taxa, whereas the largest, youngest and most diverse subfamily Cecidomyiinae includes fungivorous as well as herbivorous and predatory species. The currently accepted classification of the Cecidomyiinae is morphology-based, and the few phylogenetic inferences that have previously been suggested for it were based on fragmentary or limited datasets. In a first comprehensive phylogenetic analysis of the Cecidomyiinae we sampled 142 species representing 88 genera of 13 tribes from all feeding guilds and zoogeographic regions in order to test the validity of the systematic division of the subfamily and gain insight into patterns of diversification and the evolution of feeding modes. We used sequences from five mitochondrial and nuclear genes to reconstruct maximum likelihood and Bayesian, time-calibrated phylogenies and conducted ancestral state reconstruction of feeding modes. Our results corroborate to a great extent the morphology-based classification of the Cecidomyiinae, with strong support for all supertribes and tribes, all were apparently established in the Upper Cretaceous concordant with the major radiation of angiosperms. We infer that transitions from fungus-feeding to plant-feeding occurred only once or twice in the evolution of the subfamily and that predation evolved only once, contrary to previous hypotheses. All herbivorous clades in the subfamily are very species rich and have diversified at a significantly greater rate than expected, but we found no support for the assertion that herbivorous clades associated with symbiotic fungi in their galls diversify faster than clades that do not have such associations. Currently available data also do not support the hypothesis that symbiotic clades have broader host ranges than non-symbiotic clades.},
}
@article {pmid31448152,
year = {2019},
author = {S, J and Kk, S},
title = {Multifunctional aspects of Piriformospora indica in plant endosymbiosis.},
journal = {Mycology},
volume = {10},
number = {3},
pages = {182-190},
doi = {10.1080/21501203.2019.1600063},
pmid = {31448152},
issn = {2150-1203},
abstract = {Piriformospora indica (Hymenomycetes, Basidiomycota) is an endophytic fungus that colonises plant roots, and was originally isolated from Rajasthan desert. It is comparable to Arbuscular Mycorrhizal (AM) fungi in terms of plant growth promotional effects. P. indica has been used as an ideal example to analyse the mechanisms of mutualistic symbiosis. Major benefit of P. indica over AM fungi is that it is axenically cultivable in different synthetic and complex media. A preliminary attempt was made to scrutinise the role of P. indica co-cultivation on seedling vigour of common vegetables like Cucumis sativus L., Abelmoschus esculentus (L.) Moench, Solanum melongena L. and Capsicum annuum L. The positive effect of P. indica co-culture on seedling performance was compared to the effects of growth hormones like indole acetic acid and benzyl amino purine when supplemented to the MS medium at a concentration of 0.1 mg ml-1. An exogenous supply of auxin resulted in enhanced production of roots and cytokinin supplement favoured shoot production, whereas P. indica co-culture favoured simultaneous production of shoot and root over the control. P. indica colonisation inside the roots of C. sativus L. was also successfully established. These preliminary results indicate the prospective role of P. indica in vegetable farming through its favourable effect on plant growth.},
}
@article {pmid31447821,
year = {2019},
author = {Johansson, ON and Pinder, MIM and Ohlsson, F and Egardt, J and Töpel, M and Clarke, AK},
title = {Friends With Benefits: Exploring the Phycosphere of the Marine Diatom Skeletonema marinoi.},
journal = {Frontiers in microbiology},
volume = {10},
number = {},
pages = {1828},
doi = {10.3389/fmicb.2019.01828},
pmid = {31447821},
issn = {1664-302X},
abstract = {Marine diatoms are the dominant phytoplankton in the temperate oceans and coastal regions, contributing to global photosynthesis, biogeochemical cycling of key nutrients and minerals and aquatic food chains. Integral to the success of marine diatoms is a diverse array of bacterial species that closely interact within the diffusive boundary layer, or phycosphere, surrounding the diatom partner. Recently, we isolated seven distinct bacterial species from cultures of Skeletonema marinoi, a chain-forming, centric diatom that dominates the coastal regions of the temperate oceans. Genomes of all seven bacteria were sequenced revealing many unusual characteristics such as the existence of numerous plasmids of widely varying sizes. Here we have investigated the characteristics of the bacterial interactions with S. marinoi, demonstrating that several strains (Arenibacter algicola strain SMS7, Marinobacter salarius strain SMR5, Sphingorhabdus flavimaris strain SMR4y, Sulfitobacter pseudonitzschiae strain SMR1, Yoonia vestfoldensis strain SMR4r and Roseovarius mucosus strain SMR3) stimulate growth of the diatom partner. Testing of many different environmental factors including low iron concentration, high and low temperatures, and chemical signals showed variable effects on this growth enhancement by each bacterial species, with the most significant being light quality in which green and blue but not red light enhanced the stimulatory effect on S. marinoi growth by all bacteria. Several of the bacteria also inhibited growth of one or more of the other bacterial strains to different extents when mixed together. This study highlights the complex interactions between diatoms and their associated bacteria within the phycosphere, and that further studies are needed to resolve the underlying mechanisms for these relationships and how they might influence the global success of marine diatoms.},
}
@article {pmid31446647,
year = {2019},
author = {Lemos, LN and Medeiros, JD and Dini-Andreote, F and Fernandes, GR and Varani, AM and Oliveira, G and Pylro, VS},
title = {Genomic signatures and co-occurrence patterns of the ultra-small Saccharimonadia (CPR/Patescibacteria phylum) suggest a symbiotic lifestyle.},
journal = {Molecular ecology},
volume = {},
number = {},
pages = {},
doi = {10.1111/mec.15208},
pmid = {31446647},
issn = {1365-294X},
abstract = {The size of bacterial genomes is often associated with organismal metabolic capabilities determining ecological breadth and lifestyle. The recently proposed Candidate Phyla Radiation (CPR)/Patescibacteria encompasses mostly unculturable bacterial taxa with relatively small genome sizes with potential to co-metabolism interdependencies. Up to date, little is known about the ecology and evolution of CPR, particularly with respect to how they might interact with other taxa. Here, we reconstructed two novel genomes (namely, Candidatus Saccharibacter sossegus and Candidatus Chaer renensis) of taxa belonging to the class Saccharimonadia within the CPR/Patescibacteria using metagenomes obtained from Acid Mine Drainage (AMD). By testing the hypothesis of genome streamlining or symbiotic lifestyle, our results revealed clear signatures of gene losses in these genomes, such as those associated with de novo biosynthesis of essential amino acids, nucleotide, fatty acids, and cofactors. In addition, co-occurrence analysis provided evidence supporting potential symbioses of these organisms with Hydrotalea sp. in the AMD system. Taken together, our findings provide a better understanding of the ecology and evolution of CPR/Patescibacteria and highlight the importance of genome-reconstruction for studying metabolic interdependencies between unculturable Saccharimonadia representatives. This article is protected by copyright. All rights reserved.},
}
@article {pmid31445037,
year = {2019},
author = {Fujimoto, K and Kawaguchi, Y and Shimohigoshi, M and Gotoh, Y and Nakano, Y and Usui, Y and Hayashi, T and Kimura, Y and Uematsu, M and Yamamoto, T and Akeda, Y and Rhee, JH and Yuki, Y and Ishii, KJ and Crowe, SE and Ernst, PB and Kiyono, H and Uematsu, S},
title = {Antigen-specific Mucosal Immunity Regulates Development of Intestinal Bacteria-mediated Diseases.},
journal = {Gastroenterology},
volume = {},
number = {},
pages = {},
doi = {10.1053/j.gastro.2019.08.021},
pmid = {31445037},
issn = {1528-0012},
abstract = {BACKGROUND &amp; AIMS: Dysregulation of the microbiome has been associated with development of complex diseases such as obesity and diabetes. However, no method has been developed to control disease-associated commensal microbes. We investigated whether immunization with microbial antigens, using CpG oligodeoxynucleotides (CpG-ODN) and/or curdlan as adjuvants, induces systemic antigen-specific immunoglobulin (Ig)A and IgG production and affects development of diseases in mice.<br><br>METHODS: C57BL/6 mice were given intramuscular injections of antigens (ovalbumin, cholera toxin (CT) B-subunit, or PspA) combined with CpG-ODN and/or curdlan. Blood and fecal samples were collected weekly and antigen-specific IgG and IgA titers were measured. Lymph nodes and spleens were collected and analyzed by ELISA for antigen-specific splenic T-helper (Th)1 cells, Th17 cells, and memory B cells. Six weeks after primary immunization, mice were given a oral, nasal, or vaginal boost of ovalbumin; intestinal lamina propria, bronchial lavage, and vaginal swab samples were collected and antibodies and cytokines were measured. Some mice were also given oral CT or intranasal Streptococcus pneumoniae and the severity of diarrhea or pneumonia was analyzed. Gnotobiotic mice were gavaged with fecal material from obese individuals, which had a high abundance of Clostridium ramosum (a commensal microbe associated with obesity and diabetes), and were placed on a high-fat diet 2 weeks after immunization with C. ramosum. Intestinal tissues were collected and analyzed by quantitative real-time PCR.<br><br>RESULTS: Serum and fecal samples from mice given injections of antigens in combination with CpG-ODN and curdlan for 3 weeks contained antigen-specific IgA and IgG, and splenocytes produced IFNG and IL17A. Lamina propria, bronchial, and vaginal samples contained antigen-specific IgA following the ovalbumin boost. This immunization regimen prevented development of diarrhea following injection of CT, and inhibited lung colonization by S. pneumoniae. In gnotobiotic mice colonized with C. ramosum and placed on a high-fat diet, the mice that had been immunized with C. ramosum became less obese than the non-immunized mice.<br><br>CONCLUSIONS: Injection of mice with microbial antigens and adjuvant induces antigen-specific mucosal and systemic immune responses. Immunization with S pneumoniae antigen prevented lung infection by this bacteria, and immunization with C ramosum reduced obesity in mice colonized with this microbe and placed on a high-fat diet. This immunization approach might be used to protect against microbe-associated disorders of intestine.},
}
@article {pmid31440828,
year = {2019},
author = {Shimoda, Y and Imaizumi-Anraku, H and Hayashi, M},
title = {Kinase activity-dependent stability of calcium/calmodulin-dependent protein kinase of Lotus japonicus.},
journal = {Planta},
volume = {},
number = {},
pages = {},
doi = {10.1007/s00425-019-03264-6},
pmid = {31440828},
issn = {1432-2048},
abstract = {MAIN CONCLUSION: Accumulation of calcium/calmodulin-dependent protein kinase (CCaMK) in root cell nucleus depends on its kinase activity but not on nuclear symbiotic components crucial for nodulation. Plant calcium/calmodulin-dependent protein kinase (CCaMK) is a key regulator of symbioses with rhizobia and arbuscular mycorrhizal fungi as it decodes symbiotic calcium signals induced by microsymbionts. CCaMK is expressed mainly in root cells and localizes to the nucleus, where microsymbiont-triggered calcium oscillations occur. The molecular mechanisms that control CCaMK localization are unknown. Here, we analyzed the expression and subcellular localization of mutated CCaMK in the roots of Lotus japonicus and found a clear relation between CCaMK kinase activity and its stability. Kinase-defective CCaMK variants showed lower protein levels than the variants with kinase activity. The levels of transcripts driven by the CaMV 35S promoter were similar among the variants, indicating that stability of CCaMK is regulated post-translationally. We also demonstrated that CCaMK localized to the root cell nucleus in several symbiotic mutants, including cyclops, an interaction partner and phosphorylation target of CCaMK. Our results suggest that kinase activity of CCaMK is required not only for the activation of downstream symbiotic components but also for its stability in root cells.},
}
@article {pmid31440434,
year = {2019},
author = {Zhu, DT and Zou, C and Ban, FX and Wang, HL and Wang, XW and Liu, YQ},
title = {Conservation of transcriptional elements in the obligate symbiont of the whitefly Bemisia tabaci.},
journal = {PeerJ},
volume = {7},
number = {},
pages = {e7477},
doi = {10.7717/peerj.7477},
pmid = {31440434},
issn = {2167-8359},
abstract = {Background: Bacterial symbiosis is widespread in arthropods, especially in insects. Some of the symbionts undergo a long-term co-evolution with the host, resulting in massive genome decay. One particular consequence of genome decay is thought to be the elimination of transcriptional elements within both the coding region and intergenic sequences. In the whitefly Bemisia tabaci species complex, the obligate symbiont Candidatus Portiera aleyrodidarum is of vital importance in nutrient provision, and yet little is known about the regulatory capacities of it.<br><br>Methods: Portiera genomes of two whitefly species in China were sequenced and assembled. Gene content of these two Portiera genomes was predicted, and then subjected to Kyoto Encyclopedia of Genes and Genomes pathway analysis. Together with two other Portiera genomes from whitefly species available previously, four Portiera genomes were utilized to investigate regulatory capacities of Portiera, focusing on transcriptional elements, including genes related with transcription and functional elements within the intergenic spacers.<br><br>Results: Comparative analyses of the four Portiera genomes of whitefly B. tabaci indicate that the obligate symbionts Portiera is similar in different species of whiteflies, in terms of general genome features and possible functions in the biosynthesis of essential amino acids. The screening of transcriptional factors suggests compromised ability of Portiera to regulate the essential amino acid biosynthesis pathways. Meanwhile, thermal tolerance ability of Portiera is indicated with the detection of a σ32 factor, as well as two predicted σ32 binding sites. Within intergenic spacers, functional elements are predicted, including 37 Shine-Dalgarno sequences and 34 putative small RNAs.},
}
@article {pmid31440229,
year = {2019},
author = {Li, Y and Zhang, K and Liu, Y and Li, K and Hu, D and Wronski, T},
title = {Community Composition and Diversity of Intestinal Microbiota in Captive and Reintroduced Przewalski's Horse (Equus ferus przewalskii).},
journal = {Frontiers in microbiology},
volume = {10},
number = {},
pages = {1821},
doi = {10.3389/fmicb.2019.01821},
pmid = {31440229},
issn = {1664-302X},
abstract = {Large and complex intestinal microbiota communities in hosts have profound effects on digestion and metabolism. To better understand the community structure of intestinal microbiota in Przewalski's horse (Equus ferus przewalskii) under different feeding regimes, we compared bacterial diversity and composition between captive and reintroduced Przewalski's horses, using high-throughput 16S-rRNA gene sequencing for identification. Reintroduced Przewalski's horses were sampled in two Chinese nature reserves, i.e., Dunhuang Xihu Nature Reserve (DXNR; n = 8) in Gansu Province and Kalamaili Nature Reserve (KNR; n = 12) in Xinjiang Province, and compared to a captive population at the Przewalski's Horse Breeding Center in Xinjiang (PHBC; n = 11). The composition of intestinal microbiota in Przewalski's horses was significantly different at the three study sites. Observed species was lowest in DXNR, but highest in KNR. Lowest Shannon diversity was observed in DXNR, while in KNR and PHBC had a moderately high diversity; Simpson diversity showed an opposite trend compared with the Shannon index. Linear Discriminant Analysis effect size was used to determine differentially distributed bacterial taxa at each study site. The most dominant phyla of intestinal microbiota were similar in all feeding regimes, including mainly Firmicutes, Bacteroidetes, Verrucomicrobia, and Spirochaetes. Differing abundances of intestinal microbiota in Przewalski's horses may be related to different food types at each study site, differences in diversity may be attributed to low quality food in DXNR. Results indicated that diet is one of the important factors that can influence the structure of intestinal microbiota communities in Przewalski's horse. These findings combined with a detailed knowledge of the available and consumed food plant species could provide guidelines for the selection of potential future reintroduction sites.},
}
@article {pmid31439018,
year = {2019},
author = {Li, C and Chng, KR and Kwah, JS and Av-Shalom, TV and Tucker-Kellogg, L and Nagarajan, N},
title = {An expectation-maximization algorithm enables accurate ecological modeling using longitudinal microbiome sequencing data.},
journal = {Microbiome},
volume = {7},
number = {1},
pages = {118},
doi = {10.1186/s40168-019-0729-z},
pmid = {31439018},
issn = {2049-2618},
abstract = {BACKGROUND: The dynamics of microbial communities is driven by a range of interactions from symbiosis to predator-prey relationships, the majority of which are poorly understood. With the increasing availability of high-throughput microbiome taxonomic profiling data, it is now conceivable to directly learn the ecological models that explicitly define microbial interactions and explain community dynamics. The applicability of these approaches is severely limited by the lack of accurate absolute cell density measurements (biomass).<br><br>METHODS: We present a new computational approach that resolves this key limitation in the inference of generalized Lotka-Volterra models (gLVMs) by coupling biomass estimation and model inference with an expectation-maximization algorithm (BEEM).<br><br>RESULTS: BEEM outperforms the state-of-the-art methods for inferring gLVMs, while simultaneously eliminating the need for additional experimental biomass data as input. BEEM's application to previously inaccessible public datasets (due to the lack of biomass data) allowed us to construct ecological models of microbial communities in the human gut on a per-individual basis, revealing personalized dynamics and keystone species.<br><br>CONCLUSIONS: BEEM addresses a key bottleneck in &quot;systems analysis&quot; of microbiomes by enabling accurate inference of ecological models from high throughput sequencing data without the need for experimental biomass measurements.},
}
@article {pmid31438811,
year = {2019},
author = {Hammer, TJ and Moran, NA},
title = {Links between metamorphosis and symbiosis in holometabolous insects.},
journal = {Philosophical transactions of the Royal Society of London. Series B, Biological sciences},
volume = {374},
number = {1783},
pages = {20190068},
doi = {10.1098/rstb.2019.0068},
pmid = {31438811},
issn = {1471-2970},
support = {R01 GM108477/GM/NIGMS NIH HHS/United States ; },
abstract = {Many animals depend on microbial symbionts to provide nutrition, defence or other services. Holometabolous insects, as well as other animals that undergo metamorphosis, face unique constraints on symbiont maintenance. Microbes present in larvae encounter a radical transformation of their habitat and may also need to withstand chemical and immunological challenges. Metamorphosis also provides an opportunity, in that symbiotic associations can be decoupled over development. For example, some holometabolous insects maintain the same symbiont as larvae and adults, but house it in different tissues; in other species, larvae and adults may harbour entirely different types or numbers of microbes, in accordance with shifts in host diet or habitat. Such flexibility may provide an advantage over hemimetabolous insects, in which selection on adult-stage microbial associations may be constrained by its negative effects on immature stages, and vice versa. Additionally, metamorphosis itself can be directly influenced by symbionts. Across disparate insect taxa, microbes protect hosts from pathogen infection, supply nutrients essential for rebuilding the adult body and provide cues regulating pupation. However, microbial associations remain completely unstudied for many families and even orders of Holometabola, and future research will undoubtedly reveal more links between metamorphosis and microbiota, two widespread features of animal life. This article is part of the theme issue 'The evolution of complete metamorphosis'.},
}
@article {pmid31437925,
year = {2019},
author = {Mei, J and Xia, E},
title = {Knowledge Learning Symbiosis for Developing Risk Prediction Models from Regional EHR Repositories.},
journal = {Studies in health technology and informatics},
volume = {264},
number = {},
pages = {258-262},
doi = {10.3233/SHTI190223},
pmid = {31437925},
issn = {1879-8365},
abstract = {Secondary use of regional EHR data suffers several problems, including data selection bias and limited data size caused by data incompleteness. Here, we propose knowledge learning symbiosis (KLS) as a framework to incorporate domain knowledge to address the problems and make better secondary use of EHR data. Under the framework, we introduce three main categories of methods: knowledge injection to input features, objective functions, and output labels, where knowledge-enhanced neural network (KENN) was first introduced to inject knowledge into objective functions. A case study was conducted to build a cardiovascular disease risk prediction model on the type 2 diabetes patient cohort using regional EHR repositories. By incorporating a well-established knowledge risk model as domain knowledge under our KLS framework, we increased risk prediction performance both on small and biased data, where KENN showed the best performance among all methods.},
}
@article {pmid31437324,
year = {2019},
author = {Teotia, D and Gaid, M and Saini, SS and Verma, A and Yennamalli, RM and Khare, SP and Ambatipudi, K and Mir, JI and Beuerle, T and Hänsch, R and Roy, P and Agrawal, PK and Beerhues, L and Sircar, D},
title = {Cinnamate:CoA-ligase is involved in benzoate-derived biphenyl phytoalexin biosynthesis in Malus × domestica 'Golden Delicious' cell cultures.},
journal = {The Plant journal : for cell and molecular biology},
volume = {},
number = {},
pages = {},
doi = {10.1111/tpj.14506},
pmid = {31437324},
issn = {1365-313X},
abstract = {Apple (Malus sp.) and other genera belonging to the sub-tribe Malinae of the Rosaceous family produce unique benzoic acid-derived biphenyl phytoalexins. Cell cultures of Malus domestica cv. 'Golden Delicious' accumulate two biphenyl phytoalexins, aucuparin and noraucuparin, in response to the addition of Venturia inaequalis elicitor (VIE). In this study, we isolated and expressed a cinnamate-CoA ligase-encoding sequence in VIE-treated cell cultures of cv. 'Golden Delicious' (M. domestica CNL; MdCNL). MdCNL catalyzes the conversion of cinnamic acid into cinnamoyl-CoA, which is subsequently converted to biphenyls. MdCNL failed to accept benzoic acid as a substrate. When scab-resistant (cv. 'Shireen') and moderately scab-susceptible (cv. 'Golden Delicious') apple cultivars were challenged with the V. inaequalis scab fungus, an increase in MdCNL transcript levels was observed in internodal regions. The increase in MdCNL transcript levels could conceivably correlate with the accumulation pattern of biphenyls. C-terminal signal in the MdCNL protein directed its N-terminal reporter fusion to peroxisomes in Nicotiana benthamiana leaves. Thus, this report records the cloning and characterization of a cinnamoyl-CoA-forming enzyme from apple via a series of in vivo and in vitro studies. Defining the key step of phytoalexin formation in apple provides a biotechnological tool for engineering elite cultivars with improved resistance. This article is protected by copyright. All rights reserved.},
}
@article {pmid31437265,
year = {2019},
author = {Watanabe, D and Takagi, H},
title = {Yeast prion-based metabolic reprogramming induced by bacteria in fermented foods.},
journal = {FEMS yeast research},
volume = {},
number = {},
pages = {},
doi = {10.1093/femsyr/foz061},
pmid = {31437265},
issn = {1567-1364},
abstract = {Microbial communities of yeast and bacterial cells are often observed in the manufacturing processes of fermented foods and drinks, such as sourdough bread, cheese, kefir, wine, and sake. Community interactions and dynamics among microorganisms, as well as their significance during the manufacturing processes, are central issues in modern food microbiology. Recent studies demonstrated that emergence of a yeast prion termed [GAR+] in Saccharomyces cerevisiae is induced by coculturing with bacterial cells, resulting in switching of the carbon metabolism. In order to facilitate mutualistic symbiosis among microorganisms, this mode of microbial interaction is induced between yeasts and lactic acid bacteria species used in traditional sake making. Thus, yeast prions have attracted much attention as novel platforms that govern the metabolic adaptation of cross-kingdom ecosystems. Our mini-review focuses on the plausible linkage between fermented-food microbial communication and yeast prion-mediated metabolic reprogramming.},
}
@article {pmid31430416,
year = {2019},
author = {Reiter, S and Cahn, JKB and Wiebach, V and Ueoka, R and Piel, J},
title = {Characterization of an orphan type III polyketide synthase conserved in uncultivated 'Entotheonella' sponge symbionts.},
journal = {Chembiochem : a European journal of chemical biology},
volume = {},
number = {},
pages = {},
doi = {10.1002/cbic.201900352},
pmid = {31430416},
issn = {1439-7633},
abstract = {Uncultivated bacterial symbionts from the candidate genus 'Entotheonella' have been shown to produce diverse natural products previously attributed to their sponge hosts. In addition to these known compounds, 'Entotheonella' genomes contain rich sets of biosynthetic gene clusters lacking identified natural products. Among these is a small type III polyketide synthase (PKS) cluster, one of only three clusters present in all known 'Entotheonella' genomes. This c onserved ' E ntotheonella' P KS (cep) cluster encodes the type III PKS CepA and the putative methyltransferase CepB. Here we report the characterization of CepA as an enzyme involved in phenolic lipid biosynthesis. In vitro analysis showed a specificity for alkyl starter substrates and the production of tri- and tetraketide pyrones and tetraketide resorcinols. The conserved distribution of the cep cluster suggests an important role for the phenolic lipid polyketides produced in 'Entotheonella' variants.},
}
@article {pmid31428118,
year = {2019},
author = {Nadzieja, M and Stougaard, J and Reid, D},
title = {A Toolkit for High Resolution Imaging of Cell Division and Phytohormone Signaling in Legume Roots and Root Nodules.},
journal = {Frontiers in plant science},
volume = {10},
number = {},
pages = {1000},
doi = {10.3389/fpls.2019.01000},
pmid = {31428118},
issn = {1664-462X},
abstract = {Legume plants benefit from a nitrogen-fixing symbiosis in association with rhizobia hosted in specialized root nodules. Formation of root nodules is initiated by de novo organogenesis and coordinated infection of these developing lateral root organs by rhizobia. Both bacterial infection and nodule organogenesis involve cell cycle activation and regulation by auxin and cytokinin is tightly integrated in the process. To characterize the hormone dynamics and cell division patterns with cellular resolution during nodulation, sensitive and specific sensors suited for imaging of multicellular tissues are required. Here we report a modular toolkit, optimized in the model legume Lotus japonicus, for use in legume roots and root nodules. This toolkit includes synthetic transcriptional reporters for auxin and cytokinin, auxin accumulation sensors and cell cycle progression markers optimized for fluorescent and bright field microscopy. The developed vectors allow for efficient one-step assembly of multiple units using the GoldenGate cloning system. Applied together with a fluorescence-compatible clearing approach, these reporters improve imaging depth and facilitate fluorescence examination in legume roots. We additionally evaluate the utility of the dynamic gravitropic root response in altering the timing and location of auxin accumulation and nodule emergence. We show that alteration of auxin distribution in roots allows for preferential nodule emergence at the outer side of the bend corresponding to a region of high auxin signaling capacity. The presented tools and procedures open new possibilities for comparative mutant studies and for developing a more comprehensive understanding of legume-rhizobia interactions.},
}
@article {pmid31426312,
year = {2019},
author = {Cherif-Silini, H and Thissera, B and Bouket, AC and Saadaoui, N and Silini, A and Eshelli, M and Alenezi, FN and Vallat, A and Luptakova, L and Yahiaoui, B and Cherrad, S and Vacher, S and Rateb, ME and Belbahri, L},
title = {Durum Wheat Stress Tolerance Induced by Endophyte Pantoea agglomerans with Genes Contributing to Plant Functions and Secondary Metabolite Arsenal.},
journal = {International journal of molecular sciences},
volume = {20},
number = {16},
pages = {},
doi = {10.3390/ijms20163989},
pmid = {31426312},
issn = {1422-0067},
abstract = {In the arid region Bou-Saâda at the South of Algeria, durum wheat Triticum durum L. cv Waha production is severely threatened by abiotic stresses, mainly drought and salinity. Plant growth-promoting rhizobacteria (PGPR) hold promising prospects towards sustainable and environmentally-friendly agriculture. Using habitat-adapted symbiosis strategy, the PGPR Pantoea agglomerans strain Pa was recovered from wheat roots sampled in Bou-Saâda, conferred alleviation of salt stress in durum wheat plants and allowed considerable growth in this unhostile environment. Strain Pa showed growth up to 35 °C temperature, 5-10 pH range, and up to 30% polyethylene glycol (PEG), as well as 1 M salt concentration tolerance. Pa strain displayed pertinent plant growth promotion (PGP) features (direct and indirect) such as hormone auxin biosynthesis, production of 1-aminocyclopropane-1-carboxylate (ACC) deaminase, and ammonia and phosphate solubilization. PGPR features were stable over wide salt concentrations (0-400 mM). Pa strain was also able to survive in seeds, in the non-sterile and sterile wheat rhizosphere, and was shown to have an endophytic life style. Phylogenomic analysis of strain Pa indicated that Pantoea genus suffers taxonomic imprecision which blurs species delimitation and may have impacted their practical use as biofertilizers. When applied to plants, strain Pa promoted considerable growth of wheat seedlings, high chlorophyll content, lower accumulation of proline, and favored K+ accumulation in the inoculated plants when compared to Na+ in control non-inoculated plants. Metabolomic profiling of strain Pa under one strain many compounds (OSMAC) conditions revealed a wide diversity of secondary metabolites (SM) with interesting salt stress alleviation and PGP activities. All these findings strongly promote the implementation of Pantoea agglomerans strain Pa as an efficient biofertilizer in wheat plants culture in arid and salinity-impacted regions.},
}
@article {pmid31425566,
year = {2019},
author = {Doremus, MR and Kelly, SE and Hunter, MS},
title = {Exposure to opposing temperature extremes causes comparable effects on Cardinium density but contrasting effects on Cardinium-induced cytoplasmic incompatibility.},
journal = {PLoS pathogens},
volume = {15},
number = {8},
pages = {e1008022},
doi = {10.1371/journal.ppat.1008022},
pmid = {31425566},
issn = {1553-7374},
abstract = {Terrestrial arthropods, including insects, commonly harbor maternally inherited intracellular symbionts that confer benefits to the host or manipulate host reproduction to favor infected female progeny. These symbionts may be especially vulnerable to thermal stress, potentially leading to destabilization of the symbiosis and imposing costs to the host. For example, increased temperatures can reduce the density of a common reproductive manipulator, Wolbachia, and the strength of its crossing incompatibility (cytoplasmic incompatibility, or CI) phenotype. Another manipulative symbiont, Cardinium hertigii, infects ~ 6-10% of Arthropods, and also can induce CI, but there is little homology between the molecular mechanisms of CI induced by Cardinium and Wolbachia. Here we investigated whether temperature disrupts the CI phenotype of Cardinium in a parasitic wasp host, Encarsia suzannae. We examined the effects of both warm (32°C day/ 29°C night) and cool (20°C day/ 17°C night) temperatures on Cardinium CI and found that both types of temperature stress modified aspects of this symbiosis. Warm temperatures reduced symbiont density, pupal developmental time, vertical transmission rate, and the strength of both CI modification and rescue. Cool temperatures also reduced symbiont density, however this resulted in stronger CI, likely due to cool temperatures prolonging the host pupal stage. The opposing effects of cool and warm-mediated reductions in symbiont density on the resulting CI phenotype indicates that CI strength may be independent of density in this system. Temperature stress also modified the CI phenotype only if it occurred during the pupal stage, highlighting the likely importance of this stage for CI induction in this symbiosis.},
}
@article {pmid31419535,
year = {2019},
author = {Ikuta, T and Tame, A and Saito, M and Aoki, Y and Nagai, Y and Sugimura, M and Inoue, K and Fujikura, K and Ohishi, K and Maruyama, T and Yoshida, T},
title = {Identification of cells expressing two peptidoglycan recognition proteins in the gill of the vent mussel, Bathymodiolus septemdierum.},
journal = {Fish &amp; shellfish immunology},
volume = {93},
number = {},
pages = {815-822},
doi = {10.1016/j.fsi.2019.08.022},
pmid = {31419535},
issn = {1095-9947},
abstract = {In symbiotic systems in which symbionts are transmitted horizontally, hosts must accept symbionts from the environment while defending themselves against invading pathogenic microorganisms. How they distinguish pathogens from symbionts and how the latter evade host immune defences are not clearly understood. Recognition of foreign materials is one of the most critical steps in stimulating immune responses, and pattern recognition receptors (PRRs) play vital roles in this process. In this study, we focused on a group of highly conserved PRRs, peptidoglycan recognition proteins (PGRPs), in the deep-sea mussel, Bathymodiolus septemdierum, which harbours chemosynthetic bacteria in their gill epithelial cells. We isolated B. septemdierum PGRP genes BsPGRP-S and BsPGRP-L, which encode a short- and a long-type PGRP, respectively. The short-type PGRP has a signal peptide and was expressed in the asymbiotic goblet mucous cells in the gill epithelium, whereas the long-type PGRP was predicted to include a transmembrane domain and was expressed in gill bacteriocytes. Based on these findings, we hypothesize that the secreted and transmembrane PGRPs are engaged in host defence against pathogenic bacteria and/or in the regulation of symbiosis via different cellular localizations and mechanisms.},
}
@article {pmid31418995,
year = {2019},
author = {Liu, X and Tang, K and Zhang, D and Li, Y and Liu, Z and Yao, J and Wood, TK and Wang, X},
title = {Symbiosis of a P2-family phage and deep-sea Shewanella putrefaciens.},
journal = {Environmental microbiology},
volume = {},
number = {},
pages = {},
doi = {10.1111/1462-2920.14781},
pmid = {31418995},
issn = {1462-2920},
support = {2017YFC0506303//National Key Research and Development Program of China/ ; 2018YFC1406500//National Key Research and Development Program of China/ ; 31400162//National Natural Science Foundation of China/ ; 31625001//National Natural Science Foundation of China/ ; 41706172//National Natural Science Foundation of China/ ; 2017A030313193//Natural Science Foundation of Guangdong Province, China/ ; },
abstract = {Almost all bacterial genomes harbour prophages, yet it remains unknown why prophages integrate into tRNA-related genes. Approximately 1/3 of Shewanella isolates harbour a prophage at the tmRNA (ssrA) gene. Here, we discovered a P2-family prophage integrated at the 3'-end of ssrA in the deep-sea bacterium S. putrefaciens. We found that ~0.1% of host cells are lysed to release P2 constitutively during host growth. P2 phage production is induced by a prophage-encoded Rep protein and its excision is induced by the Cox protein. We also found that P2 genome excision leads to the disruption of wobble base pairing of SsrA due to site-specific recombination, thus disrupting the trans-translation function of SsrA. We further demonstrated that P2 excision greatly hinders growth in seawater medium and inhibits biofilm formation. Complementation with a functional SsrA in the P2-excised strain completely restores the growth defects in seawater medium and partially restores biofilm formation. Additionally, we found that products of the P2 genes also increase biofilm formation. Taken together, this study illustrates a symbiotic relationship between P2 and its marine host, thus providing multiple benefits for both sides when a phage is integrated but suffers from reduced fitness when the prophage is excised.},
}
@article {pmid31418981,
year = {2019},
author = {Chen, Q and Wu, WW and Qi, SS and Cheng, H and Li, Q and Ran, Q and Dai, ZC and Du, DL and Egan, S and Thomas, T},
title = {Arbuscular mycorrhizal fungi improve the growth and disease resistance of the invasive plant Wedelia trilobata.},
journal = {Journal of applied microbiology},
volume = {},
number = {},
pages = {},
doi = {10.1111/jam.14415},
pmid = {31418981},
issn = {1365-2672},
abstract = {AIMS: Arbuscular mycorrhizal fungi (AMF) are symbiotic partners of many invasive plants, however it is still unclear how AMF contribute to traits that are important for the successful invasion of their host and how environmental factors, such as nutrient conditions, influence this. This study was to explore the effects of Glomus versiforme (GV) and Glomus mosseae (GM) on the growth and disease resistance of the invasive plant Wedelia trilobata under different nutrient conditions.<br><br>METHODS AND RESULTS: We found that GV and GM had higher root colonization rates resulting in faster W. trilobata growth under both low-N and low-P nutrient conditions compared to the normal condition. Also, the colonization of W. trilobata by GV significantly reduced the infection area of the pathogenic fungus Rhizoctonia solani under low-N conditions.<br><br>CONCLUSIONS: These results demonstrated that AMF can promote the growth and pathogenic defense of W. trilobata in a nutrient-poor environment, which might contribute to their successful invasion into certain type of habitats.<br><br>In this study, we report for the first time that AMF can promote growth and disease resistance of W. trilobata under nutrient-poor environment, which contribute to a better understanding of plant invasion. This article is protected by copyright. All rights reserved.},
}
@article {pmid31416861,
year = {2019},
author = {Andryuschenko, SV and Ivanova, EV and Perunova, NB and Bukharin, OV},
title = {Genome Sequence and Biochemical Properties of Bifidobacterium longum Strain ICIS-505, Isolated from the Intestine of a Healthy Woman.},
journal = {Microbiology resource announcements},
volume = {8},
number = {33},
pages = {},
doi = {10.1128/MRA.00491-19},
pmid = {31416861},
issn = {2576-098X},
abstract = {This report describes the genome sequence of Bifidobacterium longum strain ICIS-505, isolated from human feces. The size of the genome was 2,448,844 bp (59.71% G+C content), including 3,751 bp of the crypto-plasmid pBL505. Annotation revealed 2,241 gene sequences, including 2,033 proteins, 7 rRNA genes, 76 tRNA genes, and 4 noncoding RNA genes.},
}
@article {pmid31416823,
year = {2019},
author = {Cope, KR and Bascaules, A and Irving, TB and Venkateshwaran, M and Maeda, J and Garcia, K and Rush, T and Ma, C and Labbe, JJ and Jawdy, S and Steigerwald, E and Setzke, J and Fung, E and Schnell, KG and Wang, Y and Schlief, N and Bücking, H and Strauss, SH and Maillet, F and Jargeat, P and Bécard, G and Puech-Pagès, V and Ane, JM},
title = {The Ectomycorrhizal Fungus Laccaria bicolor Produces Lipochitooligosaccharides and Uses the Common Symbiosis Pathway to Colonize Populus Roots.},
journal = {The Plant cell},
volume = {},
number = {},
pages = {},
doi = {10.1105/tpc.18.00676},
pmid = {31416823},
issn = {1532-298X},
abstract = {Mycorrhizal fungi form mutualistic associations with the roots of most land plants and provide them with mineral nutrients from the soil in exchange for fixed carbon derived from photosynthesis. The common symbiosis pathway (CSP) is a conserved molecular signaling pathway in all plants capable of associating with arbuscular mycorrhizal fungi . It is required not only for arbuscular mycorrhizal symbiosis but also for rhizobia-legume and actinorhizal symbioses. Given its role in such diverse symbiotic associations, we hypothesized that the CSP also plays a role in ectomycorrhizal associations. We showed that the ectomycorrhizal fungus Laccaria bicolor produces an array of lipochitooligosaccharides (LCOs) that can trigger both root hair branching in legumes and, most importantly, calcium spiking in the host plant Populus in a CASTOR/POLLUX-dependent manner. Nonsulfated LCOs enhanced lateral root development in Populus in a CCaMK-dependent manner, and sulfated LCOs enhanced the colonization of Populus by L. bicolor. Compared to wild-type Populus, the colonization of CASTOR/POLLUX and CCaMK RNA interference lines by L. bicolor was reduced. Our work demonstrates that similar to other root symbioses, L. bicolor uses the CSP for the full establishment of its mutualistic association with Populus.},
}
@article {pmid31416582,
year = {2019},
author = {Černajová, I and Škaloud, P},
title = {The first survey of Cystobasidiomycete yeasts in the lichen genus Cladonia; with the description of Lichenozyma pisutiana gen. nov., sp. nov.},
journal = {Fungal biology},
volume = {123},
number = {9},
pages = {625-637},
doi = {10.1016/j.funbio.2019.05.006},
pmid = {31416582},
issn = {1878-6146},
abstract = {The view of lichens as a symbiosis only between a mycobiont and a photobiont has been challenged by discoveries of diverse associated organisms. Specific basidiomycete yeasts in the cortex of a range of macrolichens were hypothesized to influence the lichens' phenotype. The present study explores the occurrence and diversity of cystobasidiomycete yeasts in the lichen genus Cladonia. We obtained seven cultures and 56 additional sequences using specific primers from 27 Cladonia species from all over Europe and performed phylogenetic analyses based on ITS, LSU and SSU rDNA loci. We revealed yeast diversity distinct from any previously reported. Representatives of Cyphobasidiales, Microsporomycetaceae and of an unknown group related to Symmetrospora have been found. We present evidence that the Microsporomycetaceae contains mainly lichen-associated yeasts. Lichenozyma pisutiana is circumscribed here as a new genus and species. We report the first known associations between cystobasidiomycete yeasts and Cladonia (both corticate and ecorticate), and find that the association is geographically widespread in various habitats. Our results also suggest that a great diversity of lichen associated yeasts remains to be discovered.},
}
@article {pmid31416417,
year = {2019},
author = {Yang, QS and Dong, JD and Ahmad, M and Ling, J and Zhou, WG and Tan, YH and Zhang, YZ and Shen, DD and Zhang, YY},
title = {Analysis of nifH DNA and RNA reveals a disproportionate contribution to nitrogenase activities by rare plankton-associated diazotrophs.},
journal = {BMC microbiology},
volume = {19},
number = {1},
pages = {188},
doi = {10.1186/s12866-019-1565-9},
pmid = {31416417},
issn = {1471-2180},
support = {XDA13020300;XDA11020202//Chinese Academy of Sciences/ ; 41676107, 41276114, and 41676163//National Natural Science Foundation of China/ ; 2017B030314052//Science and Technology Planning Project of Guangdong Province/ ; },
abstract = {BACKGROUND: Holobionts comprising nitrogen-fixing diazotrophs and phytoplankton or zooplankton are ubiquitous in the pelagic sea. However, neither the community structure of plankton-associated diazotrophs (PADs) nor their nitrogenase transcriptional activity are well-understood. In this study, we used nifH gene Illumina sequencing and quantitative PCR to characterize the community composition and nifH expression profile of PADs with > 100 μm size fraction in the euphotic zone of the northern South China Sea.<br><br>RESULTS: The results of DNA- and RNA-derived nifH gene revealed a higher alpha-diversity in the active than in the total community. Moreover, the compositional resemblance among different sites was less for active than for total communities of PADs. We characterized the 20 most abundant OTUs by ranking the sum of sequence reads across 9 sampling stations for individual OTUs in both nifH DNA and RNA libraries, and then assessed their phylogenetic relatedness. Eight of the 20 abundant OTUs were phylogenetically affiliated with Trichodesmium and occurred in approximately equal proportion in both the DNA and RNA libraries. The analysis of nifH gene expression level showed uneven attribute of the abundance and nitrogenase activities by the remaining 12 OTUs. Taxa belonging to cluster III and Betaproteobacteria were present at moderate abundance but exhibited negligible nitrogenase transcription activity. Whereas, the abundances of Richelia, Deltaproteobacteria and Gammaproteobacteria were low but the contribution of these groups to nitrogenase transcription was disproportionately high.<br><br>CONCLUSIONS: The substantial variation in community structure among active dizatrophic fractions compared to the total communities suggests that the former are better indicators of biological response to environmental changes. Altogether, our study highlights the importance of rare PADs groups in nitrogen fixation in plankton holobionts, evidenced by their high level of nitrogenase transcription.},
}
@article {pmid31416010,
year = {2019},
author = {Ruszkiewicz, JA and Tinkov, AA and Skalny, AV and Siokas, V and Dardiotis, E and Tsatsakis, A and Bowman, AB and da Rocha, JBT and Aschner, M},
title = {Brain diseases in changing climate.},
journal = {Environmental research},
volume = {177},
number = {},
pages = {108637},
doi = {10.1016/j.envres.2019.108637},
pmid = {31416010},
issn = {1096-0953},
support = {R01 ES007331/ES/NIEHS NIH HHS/United States ; R01 ES010563/ES/NIEHS NIH HHS/United States ; R01 ES020852/ES/NIEHS NIH HHS/United States ; },
abstract = {Climate change is one of the biggest and most urgent challenges for the 21st century. Rising average temperatures and ocean levels, altered precipitation patterns and increased occurrence of extreme weather events affect not only the global landscape and ecosystem, but also human health. Multiple environmental factors influence the onset and severity of human diseases and changing climate may have a great impact on these factors. Climate shifts disrupt the quantity and quality of water, increase environmental pollution, change the distribution of pathogens and severely impacts food production - all of which are important regarding public health. This paper focuses on brain health and provides an overview of climate change impacts on risk factors specific to brain diseases and disorders. We also discuss emerging hazards in brain health due to mitigation and adaptation strategies in response to climate changes.},
}
@article {pmid31415751,
year = {2019},
author = {Cheng, YT and Zhang, L and He, SY},
title = {Plant-Microbe Interactions Facing Environmental Challenge.},
journal = {Cell host &amp; microbe},
volume = {26},
number = {2},
pages = {183-192},
doi = {10.1016/j.chom.2019.07.009},
pmid = {31415751},
issn = {1934-6069},
support = {R01 GM109928/GM/NIGMS NIH HHS/United States ; },
abstract = {In the past four decades, tremendous progress has been made in understanding how plants respond to microbial colonization and how microbial pathogens and symbionts reprogram plant cellular processes. In contrast, our knowledge of how environmental conditions impact plant-microbe interactions is less understood at the mechanistic level, as most molecular studies are performed under simple and static laboratory conditions. In this review, we highlight research that begins to shed light on the mechanisms by which environmental conditions influence diverse plant-pathogen, plant-symbiont, and plant-microbiota interactions. There is a great need to increase efforts in this important area of research in order to reach a systems-level understanding of plant-microbe interactions that are more reflective of what occurs in nature.},
}
@article {pmid31415746,
year = {2019},
author = {Fleming, BA and Mulvey, MA},
title = {Commensal Strains of Neisseria Use DNA to Poison Their Pathogenic Rivals.},
journal = {Cell host &amp; microbe},
volume = {26},
number = {2},
pages = {156-158},
doi = {10.1016/j.chom.2019.07.014},
pmid = {31415746},
issn = {1934-6069},
mesh = {DNA ; *Neisseria ; Neisseria gonorrhoeae ; *Poisons ; Symbiosis ; },
abstract = {Commensal bacteria can interfere with colonization of the host by infiltrating pathogens. In this issue of Cell Host &amp; Microbe, Kim et al. (2019) describe an intriguing mechanism of colonization resistance driven by the mismatching of methylation patterns following uptake of commensal-derived DNA by pathogenic strains of Neisseria.},
}
@article {pmid31413521,
year = {2019},
author = {Boem, F and Amedei, A},
title = {Healthy axis: Towards an integrated view of the gut-brain health.},
journal = {World journal of gastroenterology},
volume = {25},
number = {29},
pages = {3838-3841},
doi = {10.3748/wjg.v25.i29.3838},
pmid = {31413521},
issn = {2219-2840},
abstract = {Despite the lack of precise mechanisms of action, a growing number of studies suggests that gut microbiota is involved in a great number of physiological functions of the human organism. In fact, the composition and the relations of intestinal microbial populations play a role, either directly or indirectly, to both the onset and development of various pathologies. In particular, the gastrointestinal tract and nervous system are closely connected by the so-called gut-brain axis, a complex bidirectional system in which the central and enteric nervous system interact with each other, also engaging endocrine, immune and neuronal circuits. This allows us to put forward new working hypotheses on the origin of some multifactorial diseases: from eating to neuropsychiatric disorders (such as autism spectrum disorders and depression) up to diabetes and tumors (such as colorectal cancer). This scenario reinforces the idea that the microbiota and its composition represent a factor, which is no longer negligible, not only in preserving what we call &quot;health&quot; but also in defining and thus determining it. Therefore, we propose to consider the gut-brain axis as the focus of new scientific and clinical investigation as long as the locus of possible systemic therapeutic interventions.},
}
@article {pmid31412166,
year = {2019},
author = {McIntire, PJ},
title = {Mankind and the machine: A relationship of symbiosis or conflict?.},
journal = {Cancer cytopathology},
volume = {},
number = {},
pages = {},
doi = {10.1002/cncy.22175},
pmid = {31412166},
issn = {1934-6638},
}
@article {pmid31410554,
year = {2019},
author = {Salloum, MS and Insani, M and Monteoliva, MI and Menduni, MF and Silvente, S and Carrari, F and Luna, C},
title = {Metabolic responses to arbuscular mycorrhizal fungi are shifted in roots of contrasting soybean genotypes.},
journal = {Mycorrhiza},
volume = {},
number = {},
pages = {},
doi = {10.1007/s00572-019-00909-y},
pmid = {31410554},
issn = {1432-1890},
abstract = {Modern breeding programs have reduced genetic variability and might have caused a reduction in plant colonization by arbuscular mycorrhizal fungi (AM). In our previous studies, mycorrhizal colonization was affected in improved soybean genotypes, mainly arbuscule formation. Despite substantial knowledge of the symbiosis-related changes of the transcriptome and proteome, only sparse clues regarding metabolite alterations are available. Here, we evaluated metabolite changes between improved (I-1) and unimproved (UI-4) soybean genotypes and also compare their metabolic responses after AM root colonization. Soybean genotypes inoculated or not with AM were grown in a chamber under controlled light and temperature conditions. At 20 days after inoculation, we evaluated soluble metabolites of each genotype and treatment measured by GC-MS. In this analysis, when comparing non-AM roots between genotypes, I-1 had a lower amount of 31 and higher amount of only 4 metabolites than the UI-4 genotype. When comparing AM roots, I-1 had a lower amount of 36 and higher amount of 4 metabolites than UI-4 (different to those found altered in non-AM treated plants). Lastly, comparing the AM vs non-AM treatments, I-1 had increased levels of three and reduced levels of 24 metabolites, while UI-4 only had levels of 12 metabolites reduced by the effect of mycorrhizas. We found the major changes in sugars, polyols, amino acids, and carboxylic acids. In a targeted analysis, we found lower levels of isoflavonoids and alpha-tocopherol and higher levels of malondialdehyde in the I-1 genotype that can affect soybean-AM symbiosis. Our studies have the potential to support improving soybean with a greater capacity to be colonized and responsive to AM interaction.},
}
@article {pmid31409660,
year = {2019},
author = {Zhang, S and Song, W and Wemheuer, B and Reveillaud, J and Webster, N and Thomas, T},
title = {Comparative Genomics Reveals Ecological and Evolutionary Insights into Sponge-Associated Thaumarchaeota.},
journal = {mSystems},
volume = {4},
number = {4},
pages = {},
doi = {10.1128/mSystems.00288-19},
pmid = {31409660},
issn = {2379-5077},
abstract = {Thaumarchaeota are frequently reported to associate with marine sponges (phylum Porifera); however, little is known about the features that distinguish them from their free-living thaumarchaeal counterparts. In this study, thaumarchaeal metagenome-assembled genomes (MAGs) were reconstructed from metagenomic data sets derived from the marine sponges Hexadella detritifera, Hexadella cf. detritifera, and Stylissa flabelliformis Phylogenetic and taxonomic analyses revealed that the three thaumarchaeal MAGs represent two new species within the genus Nitrosopumilus and one novel genus, for which we propose the names &quot;CandidatusUNitrosopumilus hexadellus,&quot; &quot;CandidatusUNitrosopumilus detritiferus,&quot; and &quot;CandidatusUCenporiarchaeum stylissum&quot; (the U superscript indicates that the taxon is uncultured). Comparison of these genomes to data from the Sponge Earth Microbiome Project revealed that &quot;CaUCenporiarchaeum stylissum&quot; has been exclusively detected in sponges and can hence be classified as a specialist, while &quot;CaUNitrosopumilus detritiferus&quot; and &quot;CaUNitrosopumilus hexadellus&quot; are also detected outside the sponge holobiont and likely lead a generalist lifestyle. Comparison of the sponge-associated MAGs to genomes of free-living Thaumarchaeota revealed signatures that indicate functional features of a sponge-associated lifestyle, and these features were related to nutrient transport and metabolism, restriction-modification, defense mechanisms, and host interactions. Each species exhibited distinct functional traits, suggesting that they have reached different stages of evolutionary adaptation and/or occupy distinct ecological niches within their sponge hosts. Our study therefore offers new evolutionary and ecological insights into the symbiosis between sponges and their thaumarchaeal symbionts.IMPORTANCE Sponges represent ecologically important models to understand the evolution of symbiotic interactions of metazoans with microbial symbionts. Thaumarchaeota are commonly found in sponges, but their potential adaptations to a host-associated lifestyle are largely unknown. Here, we present three novel sponge-associated thaumarchaeal species and compare their genomic and predicted functional features with those of closely related free-living counterparts. We found different degrees of specialization of these thaumarchaeal species to the sponge environment that is reflected in their host distribution and their predicted molecular and metabolic properties. Our results indicate that Thaumarchaeota may have reached different stages of evolutionary adaptation in their symbiosis with sponges.},
}
@article {pmid31409658,
year = {2019},
author = {Gorman, R},
title = {What's in it for the animals? Symbiotically considering 'therapeutic' human-animal relations within spaces and practices of care farming.},
journal = {Medical humanities},
volume = {45},
number = {3},
pages = {313-325},
doi = {10.1136/medhum-2018-011627},
pmid = {31409658},
issn = {1473-4265},
abstract = {Human-animal relations are increasingly imbricated, encountered and experienced in the production of medicine and health. Drawing on an empirical study of care farms in the UK, this article uses the language of symbiosis to develop a framework for critically considering the relationships enrolled within interspecies therapeutic practices. Care farming is an emerging paradigm that aims to deploy farming practices as a form of therapeutic intervention, with human-animal relations framed as providing important opportunities for human health. This article moves to attend to multispecies therapeutic interventions and relationships from a more-than-human perspective, drawing attention to the often-troubling anthropocentrism in which such practices are framed and performed. Attempting to perform and realise human imaginations of 'therapeutic' affects, spaces and relationships can rely on processes that reduce animals' own opportunities for flourishing. Yet, the therapeutic use of other species does not have to be forever anthropocentric or utilitarian. The article explores whether relations between humans and animals might result in a level of mutual proliferation of affective capacities, reciprocally beneficial. These human-animal entanglements highlight opportunities to think more critically about how to practice interspecies relationships and practices in ways that are less parasitic, and instead framed more by attempts at producing opportunities for mutualistic flourishing.},
}
@article {pmid31409030,
year = {2019},
author = {Dalit, M and Keren, ML and Eviatar, W and Hiba, WB and Gal, E and Ehud, B and Yossi, L and Oren, L},
title = {The Algal Symbiont Modifies the Transcriptome of the Scleractinian Coral Euphyllia paradivisa During Heat Stress.},
journal = {Microorganisms},
volume = {7},
number = {8},
pages = {},
doi = {10.3390/microorganisms7080256},
pmid = {31409030},
issn = {2076-2607},
abstract = {The profound mutualistic symbiosis between corals and their endosymbiotic counterparts, Symbiodiniaceae algae, has been threatened by the increase in seawater temperatures, leading to breakdown of the symbiotic relationship-coral bleaching. To characterize the heat-stress response of the holobiont, we generated vital apo-symbiotic Euphylliaparadivisa corals that lacked the endosymbiotic algae. Using RNA sequencing, we analyzed the gene expression of these apo-symbionts vs. symbiotic ones, to test the effect of the algal presence on the tolerance of the coral. We utilized literature-derived lists of &quot;symbiosis differentially expressed genes&quot; and &quot;coral heat-stress genes&quot; in order to compare between the treatments. The symbiotic and apo-symbiotic samples were segregated into two separate groups with several different enriched gene ontologies. Our findings suggest that the presence of endosymbionts has a greater negative impact on the host than the environmental temperature conditions experienced by the holobiont. The peak of the stress reaction was identified as 28 °C, with the highest number of differentially expressed genes. We suggest that the algal symbionts increase coral holobiont susceptibility to elevated temperatures. Currently, we can only speculate whether coral species, such as E.paradivisa, with the plasticity to also flourish as apo-symbionts, may have a greater chance to withstand the upcoming global climate change challenge.},
}
@article {pmid31408529,
year = {2019},
author = {Mestre, A and Poulin, R and Holt, RD and Barfield, M and Clamp, JC and Fernandez-Leborans, G and Mesquita-Joanes, F},
title = {The interplay of nested biotic interactions and the abiotic environment regulates populations of a hypersymbiont.},
journal = {The Journal of animal ecology},
volume = {},
number = {},
pages = {},
doi = {10.1111/1365-2656.13091},
pmid = {31408529},
issn = {1365-2656},
abstract = {1.The role of biotic interactions in shaping the distribution and abundance of species should be particularly pronounced in symbionts. Indeed, symbionts have a dual niche composed of traits of their individual hosts and the abiotic environment external to the host, and often combine active dispersal at finer scales with host-mediated dispersal at broader scales. The biotic complexity in the determinants of species distribution and abundance should be even more pronounced for hypersymbionts (symbionts of other symbionts). 2.We use a chain of symbiosis to explore the relative influence of nested biotic interactions and the abiotic environment on occupancy and abundance of a hypersymbiont. 3.Our empirical system is the epibiont ciliate Lagenophrys discoidea, which attaches to an ostracod that is itself ectosymbiotic on crayfish (the basal host). We applied multimodel selection and variance partitioning for GLMM to assess the relative importance of: 1) traits of symbiotic hosts (ostracod sex and abundance), 2) traits of basal hosts (crayfish body weight, abundance and intermoult stage), 3) the abiotic environment (water chemistry and climate), and 4) geospatial autocorrelation patterns (capturing potential effects of crayfish dispersal among localities). 4.Our models explained about half of the variation in prevalence and abundance of the hypersymbiont. Variation in prevalence was partly explained, in decreasing order of importance (18-4%) by shared effects of symbiotic host traits and the abiotic environment, pure fixed effects of symbiotic hosts, abiotic environment and geospatial patterns (traits of basal hosts were not relevant). Hypersymbiont abundance was most strongly explained by random effects of host traits (mainly the symbiotic host), in addition to weaker fixed effects (mostly abiotic environment). 5.Our results highlight the major role of the interplay between abundance of symbiotic hosts and water physico-chemistry in regulating populations of a hypersymbiotic ciliate, which is likely critical for dispersal dynamics, availability of attachment resources and suitability of on-host living conditions for the ciliate. We also found moderate signal of regulation by the basal host, for which we propose three mechanisms: 1) modulation of microhabitat suitability (crayfish-created water currents); 2) concentration of symbiotic hosts within crayfish; and 3) dispersal mediated by crayfish. This article is protected by copyright. All rights reserved.},
}
@article {pmid31407021,
year = {2019},
author = {Bockoven, AA and Bondy, EC and Flores, MJ and Kelly, SE and Ravenscraft, AM and Hunter, MS},
title = {What Goes Up Might Come Down: the Spectacular Spread of an Endosymbiont Is Followed by Its Decline a Decade Later.},
journal = {Microbial ecology},
volume = {},
number = {},
pages = {},
doi = {10.1007/s00248-019-01417-4},
pmid = {31407021},
issn = {1432-184X},
support = {DEB-1020460//Division of Environmental Biology/ ; IOS-1256905//Division of Integrative Organismal Systems/ ; },
abstract = {Facultative, intracellular bacterial symbionts of arthropods may dramatically affect host biology and reproduction. The length of these symbiont-host associations may be thousands to millions of years, and while symbiont loss is predicted, there have been very few observations of a decline of symbiont infection rates. In a population of the sweet potato whitefly species (Bemisia tabaci MEAM1) in Arizona, USA, we documented the frequency decline of a strain of Rickettsia in the Rickettsia bellii clade from near-fixation in 2011 to 36% of whiteflies infected in 2017. In previous studies, Rickettsia had been shown to increase from 1 to 97% from 2000 to 2006 and remained at high frequency for at least five years. At that time, Rickettsia infection was associated with both fitness benefits and female bias. In the current study, we established matrilines of whiteflies from the field (2016, Rickettsia infection frequency = 58%) and studied (a) Rickettsia vertical transmission, (b) fitness and sex ratios associated with Rickettsia infection, (c) symbiont titer, and (d) bacterial communities within whiteflies. The vertical transmission rate was high, approximately 98%. Rickettsia infection in the matrilines was not associated with fitness benefits or sex ratio bias and appeared to be slightly costly, as more Rickettsia-infected individuals produced non-hatching eggs. Overall, the titer of Rickettsia in the matrilines was lower in 2016 than in the whiteflies collected in 2011, but the titer distribution appeared bimodal, with high- and low-titer lines, and constancy of the average titer within lines over three generations. We found neither association between Rickettsia titer and fitness benefits or sex ratio bias nor evidence that Rickettsia was replaced by another secondary symbiont. The change in the interaction between symbiont and host in 2016 whiteflies may explain the drop in symbiont frequency we observed.},
}
@article {pmid31406945,
year = {2019},
author = {Cecchi, G and Di Piazza, S and Marescotti, P and Zotti, M},
title = {Evidence of pyrite dissolution by Telephora terrestris Ehrh in the Libiola mine (Sestri Levante, Liguria, Italy).},
journal = {Heliyon},
volume = {5},
number = {8},
pages = {e02210},
doi = {10.1016/j.heliyon.2019.e02210},
pmid = {31406945},
issn = {2405-8440},
abstract = {Evidence of pyrite dissolution by Telephora terrestris Ehrh were observed for the first time in the abandoned sulphide Libiola mine in May 2017 (Sestri Levante, Liguria, Italy). This fungus is an ectomycorrhizal species able to colonize this extreme environment and bioaccumulate metals such as copper and silver in its fruiting bodies, and it is known to establish symbiosis with maritime pines present in the area, thus favouring their recolonization of the site. This paper presents evidence of T. terrestris promoted dissolution of sulphide minerals. This species can remove from soil not only metals possibly toxic to the pine trees, but it can also contribute to the ions bioaccumulation through the bioweathering of sulphide mineral grains (especially pyrite).},
}
@article {pmid31405380,
year = {2019},
author = {Dang, X and Xie, Z and Liu, W and Sun, Y and Liu, X and Zhu, Y and Staehelin, C},
title = {The genome of Ensifer alkalisoli YIC4027 provides insights for host specificity and environmental adaptations.},
journal = {BMC genomics},
volume = {20},
number = {1},
pages = {643},
doi = {10.1186/s12864-019-6004-7},
pmid = {31405380},
issn = {1471-2164},
support = {U1806206//NSFC-Shandong Joint Fund Key Projects/ ; 31570063 and 31870020//National Natural Science Foundation of China/ ; KFZD-SW-112//Key Deployment Project of Chinese Academy of Sciences/ ; 2017GSF17129//Shandong Key Research and Development Program/ ; 2017CXGC0303//Shandong Key Scientific and Technological Innovation Program/ ; },
abstract = {BACKGROUND: Ensifer alkalisoli YIC4027, a recently characterized nitrogen-fixing bacterium of the genus Ensifer, has been isolated from root nodules of the host plant Sesbania cannabina. This plant is widely used as green manure and for soil remediation. E. alkalisoli YIC4027 can grow in saline-alkaline soils and is a narrow-host-range strain that establishes a symbiotic relationship with S. cannabina. The complete genome of this strain was sequenced to better understand the genetic basis of host specificity and adaptation to saline-alkaline soils.<br><br>RESULTS: E. alkalisoli YIC4027 was found to possess a 6.1-Mb genome consisting of three circular replicons: one chromosome (3.7 Mb), a chromid (1.9 Mb) and a plasmid (0.46 Mb). Genome comparisons showed that strain YIC4027 is phylogenetically related to broad-host-range Ensifer fredii strains. Synteny analysis revealed a strong collinearity between chromosomes of E. alkalisoli YIC4027 and those of the E. fredii NGR234 (3.9 Mb), HH103 (4.3 Mb) and USDA257 (6.48 Mb) strains. Notable differences were found for genes required for biosynthesis of nodulation factors and protein secretion systems, suggesting a role of these genes in host-specific nodulation. In addition, the genome analysis led to the identification of YIC4027 genes that are presumably related to adaptation to saline-alkaline soils, rhizosphere colonization and nodulation competitiveness. Analysis of chemotaxis cluster genes and nodulation tests with constructed che gene mutants indicated a role of chemotaxis and flagella-mediated motility in the symbiotic association between YIC4027 and S. cannabina.<br><br>CONCLUSIONS: This study provides a basis for a better understanding of host specific nodulation and of adaptation to a saline-alkaline rhizosphere. This information offers the perspective to prepare optimal E. alkalisoli inocula for agriculture use and soil remediation.},
}
@article {pmid31405202,
year = {2019},
author = {Miura, C and Saisho, M and Yagame, T and Yamato, M and Kaminaka, H},
title = {Bletilla striata (Orchidaceae) Seed Coat Restricts the Invasion of Fungal Hyphae at the Initial Stage of Fungal Colonization.},
journal = {Plants (Basel, Switzerland)},
volume = {8},
number = {8},
pages = {},
doi = {10.3390/plants8080280},
pmid = {31405202},
issn = {2223-7747},
support = {15K14550//Japan Society for the Promotion of Science/ ; 201801755//Japan Society for the Promotion of Science/ ; 18J01755//Japan Society for the Promotion of Science/ ; n/a//Tottori Prefecture Research Fund for the Promotion of Environmental Academic Research/ ; },
abstract = {Orchids produce minute seeds that contain limited or no endosperm, and they must form an association with symbiotic fungi to obtain nutrients during germination and subsequent seedling growth under natural conditions. Orchids need to select an appropriate fungus among diverse soil fungi at the germination stage. However, there is limited understanding of the process by which orchids recruit fungal associates and initiate the symbiotic interaction. This study aimed to better understand this process by focusing on the seed coat, the first point of fungal attachment. Bletilla striata seeds, some with the seed coat removed, were prepared and sown with symbiotic fungi or with pathogenic fungi. The seed coat-stripped seeds inoculated with the symbiotic fungi showed a lower germination rate than the intact seeds, and proliferated fungal hyphae were observed inside and around the stripped seeds. Inoculation with the pathogenic fungi increased the infection rate in the seed coat-stripped seeds. The pathogenic fungal hyphae were arrested at the suspensor side of the intact seeds, whereas the seed coat-stripped seeds were subjected to severe infestation. These results suggest that the seed coat restricts the invasion of fungal hyphae and protects the embryo against the attack of non-symbiotic fungi.},
}
@article {pmid31404343,
year = {2019},
author = {Wilker, J and Navabi, A and Rajcan, I and Marsolais, F and Hill, B and Torkamaneh, D and Pauls, KP},
title = {Agronomic Performance and Nitrogen Fixation of Heirloom and Conventional Dry Bean Varieties Under Low-Nitrogen Field Conditions.},
journal = {Frontiers in plant science},
volume = {10},
number = {},
pages = {952},
doi = {10.3389/fpls.2019.00952},
pmid = {31404343},
issn = {1664-462X},
abstract = {Common beans (Phaseolus vulgaris) form a relationship with nitrogen-fixing rhizobia and through a process termed symbiotic nitrogen fixation (SNF) which provides them with a source of nitrogen. However, beans are considered poor nitrogen fixers, and modern production practices involve routine use of N fertilizer, which leads to the down-regulation of SNF. High-yielding, conventionally bred bean varieties are developed using conventional production practices and selection criteria, typically not including SNF efficiency, and may have lost this trait over decades of modern breeding. In contrast, heirloom bean genotypes were developed before the advent of modern production practices and may represent an underutilized pool of genetics which could be used to improve SNF. This study compared the SNF capacity under low-N field conditions, of collections of heirloom varieties with and conventionally bred dry bean varieties. The heirloom-conventional panel (HCP) consisted of 42 genotypes from various online seed retailers or from the University of Guelph Bean Breeding program seedbank. The HCP was genotyped using a single nucleotide polymorphism (SNP) array to investigate genetic relatedness within the panel. Field trials were conducted at three locations in ON, Canada from 2014 to 2015 and various agronomic and seed composition traits were measured, including capacity for nitrogen fixation (using the natural abundance method to measure seed N isotope ratios). Significant variation for SNF was found in the panel. However, on average, heirloom genotypes did not fix significantly more nitrogen than conventionally bred varieties. However, five heirloom genotypes fixed >60% of their nitrogen from the atmosphere. Yield (kg ha-1) was not significantly different between heirloom and conventional genotypes, suggesting that incorporating heirloom genotypes into a modern breeding program would not negatively impact yield. Nitrogen fixation was significantly higher among Middle American genotypes than among Andean genotypes, confirming previous findings. The best nitrogen fixing line was Coco Sophie, a European heirloom white bean whose genetic makeup is admixed between the Andean and Middle American genepools. Heirloom genotypes represent a useful source of genetics to improve SNF in modern bean breeding.},
}
@article {pmid31400717,
year = {2019},
author = {Irshad, S and Xie, Z and Wang, J and Nawaz, A and Luo, Y and Wang, Y and Mehmood, S and Faheem, },
title = {Indigenous strain Bacillus XZM assisted phytoremediation and detoxification of arsenic in Vallisneria denseserrulata.},
journal = {Journal of hazardous materials},
volume = {381},
number = {},
pages = {120903},
doi = {10.1016/j.jhazmat.2019.120903},
pmid = {31400717},
issn = {1873-3336},
abstract = {The symbiosis between Vallisneria denseserrulata and indigenous Bacillus sp. XZM was investigated for arsenic removal for the first time. It was found that the native bacterium was able to reduce arsenic toxicity to the plant by producing higher amount of extra cellular polymeric substances (EPS), indole-3-acetic acid (IAA) and siderosphore. Interestingly, V. denseserrulata-Bacillus sp. XZM partnership showed significantly higher arsenic uptake and removal efficiency. The shift in FT-IR spectra indicated the involvement of amide, carboxyl, hydroxyl and thiol groups in detoxification of arsenic, and the existence of an arsenic metabolizing process in V. denseserrulata leaves. The scanning electron microscopy (SEM) images further confirmed that the bacterium colonized on plant roots and facilitated arsenic uptake by plant under inoculation condition. In plant, most of the arsenic existed as As(III) (85%) and was massively (>77%) found in vacuole of particularly leaves cells. Thus, these findings are highly suggested for arsenic remediation in the constructed wetlands.},
}
@article {pmid31400692,
year = {2019},
author = {Xiang, N and Jiang, C and Huang, W and Nordhaus, I and Zhou, H and Drews, M and Diao, X},
title = {The impact of acute benzo(a)pyrene on antioxidant enzyme and stress-related genes in tropical stony corals (Acropora spp.).},
journal = {The Science of the total environment},
volume = {694},
number = {},
pages = {133474},
doi = {10.1016/j.scitotenv.2019.07.280},
pmid = {31400692},
issn = {1879-1026},
abstract = {Coral reefs have extremely high ecological value in tropical and subtropical waters worldwide. However, they have been subjected to the most extensive and prolonged damage in recent decades. Polycyclic aromatic hydrocarbons (PAHs) are ubiquitous hazardous pollutants and are highly resistant to degradation in marine environments. Among these compounds, benzo(a)pyrene (BaP) has exerted pressure on corals due to water discharges, oil spills and coastal tourism. In the present study, the physiological response, oxidative stress and stress-related genetic expressions of two Acropora spp. (Acropora formosa and Acropora nasuta) were analysed. These two coral species were exposed to 10 and 40 μg·L-1 BaP for 24 hand 72 h, respectively. The results show that (1) BaP affects the health of the zooxanthellae in coral symbiosis after BaP exposure for 72 h due to a significant decline in chlorophyll a concentrations in Acropora spp. during this period. (2) An exposure of 10 μg·L-1 BaP for 24 h induced serious oxidative damage to Acropora spp., with a significant decline and increase in superoxide dismutase (SOD) activities in A. formosa and A. nasuta. (3) The P-gp gene is more sensitive in A. formosa, while the Hsp70 gene is more sensitive in A. nasuta. (4) A. formosa showed a lower ability to resist organic pollutants in coral reefs. Overall, further ecotoxicological studies are needed to investigate the impact of chemical pollutants on corals and to compare their different response mechanisms.},
}
@article {pmid31400167,
year = {2019},
author = {Schwartzman, JA and Lynch, JB and Flores Ramos, S and Zhou, L and Apicella, MA and Yew, JY and Ruby, EG},
title = {Acidic pH promotes lipopolysaccharide modification and alters colonization in a bacteria-animal mutualism.},
journal = {Molecular microbiology},
volume = {},
number = {},
pages = {},
doi = {10.1111/mmi.14365},
pmid = {31400167},
issn = {1365-2958},
support = {GM008505/GM/NIGMS NIH HHS/United States ; GM119238/GM/NIGMS NIH HHS/United States ; GM135254/GM/NIGMS NIH HHS/United States ; AI055397//National Institute of Allergy and Infectious Diseases/ ; AI50661//National Institute of Allergy and Infectious Diseases/ ; //Division of Integrative Organismal Systems/ ; OD11024//NIH Office of the Director/ ; P20 GM103449/GM/NIGMS NIH HHS/United States ; R01 AI050661/AI/NIAID NIH HHS/United States ; R01 OD011024/OD/NIH HHS/United States ; R37 AI050661/AI/NIAID NIH HHS/United States ; },
abstract = {Environmental pH can be an important cue for symbiotic bacteria as they colonize their eukaryotic hosts. Using the model mutualism between the marine bacterium Vibrio fischeri and the Hawaiian bobtail squid, we characterized the bacterial transcriptional response to acidic pH experienced during the shift from planktonic to host-associated lifestyles. We found several genes involved in outer membrane structure were differentially expressed based on pH, indicating alterations in membrane physiology as V. fischeri initiates its symbiotic program. Exposure to host-like pH increased the resistance of V. fischeri to the cationic antimicrobial peptide polymixin B, which resembles antibacterial molecules that are produced by the squid to select V. fischeri from the ocean microbiota. Using a forward genetic screen, we identified a homolog of eptA, a predicted phosphoethanolamine transferase, as critical for antimicrobial defense. We used MALDI-MS to verify eptA as an ethanolamine transferase for the lipid-A portion of V. fischeri lipopolysaccharide. We then used a DNA pulldown approach to discover that eptA transcription is activated by the global regulator H-NS. Finally, we revealed that eptA promotes successful squid colonization by V. fischeri, supporting its potential role in initiation of this highly specific symbiosis.},
}
@article {pmid31397886,
year = {2019},
author = {Cohen, ML and Mashanova, EV and Rosen, NM and Soto, W},
title = {Adaptation to temperature stress by Vibrio fischeri facilitates this microbe's symbiosis with the Hawaiian bobtail squid (Euprymna scolopes).},
journal = {Evolution; international journal of organic evolution},
volume = {},
number = {},
pages = {},
doi = {10.1111/evo.13819},
pmid = {31397886},
issn = {1558-5646},
support = {120084//College of William and Mary/ ; 120819//College of William and Mary/ ; },
abstract = {For microorganisms cycling between free-living and host-associated stages, where reproduction occurs in both of these lifestyles, an interesting inquiry is whether adaptation to stress during the free-living stage can impact microbial fitness in the host. To address this topic, the mutualism between the Hawaiian bobtail squid (Euprymna scolopes) and the marine bioluminescent bacterium Vibrio fischeri was utilized. Using microbial experimental evolution, V. fischeri was selected to low (8°C), high (34°C), and fluctuating temperature stress (8°C/34°C) for 2000 generations. The temperatures 8°C and 34°C were the lower and upper growth limits, respectively. V. fischeri was also selected to benign temperatures (21°C and 28°C) for 2000 generations, which served as controls. V. fischeri demonstrated significant adaptation to low, high, and fluctuating temperature stress. V. fischeri did not display significant adaptation to the benign temperatures. Adaptation to stressful temperatures facilitated V. fischeri's ability to colonize the squid host relative to the ancestral lines. Bioluminescence levels also increased. Evolution to benign temperatures did not manifest these results. In summary, microbial adaptation to stress during the free-living stage can promote coevolution between hosts and microorganisms.},
}
@article {pmid31396616,
year = {2019},
author = {Lallemand, F and Logacheva, M and Le Clainche, I and Bérard, A and Zheleznaia, E and May, M and Jakalski, M and Delannoy, É and Le Paslier, MC and Selosse, MA},
title = {Thirteen new plastid genomes from mixotrophic and autotrophic species provide insights into heterotrophy evolution in Neottieae orchids.},
journal = {Genome biology and evolution},
volume = {},
number = {},
pages = {},
doi = {10.1093/gbe/evz170},
pmid = {31396616},
issn = {1759-6653},
abstract = {Mixotrophic species use both organic and mineral carbon sources. Some mixotrophic plants combine photosynthesis and a nutrition called mycoheterotrophy, where carbon is obtained from fungi forming mycorrhizal symbiosis with their roots. These species can lose photosynthetic abilities and evolve full mycoheterotrophy. Besides morphological changes, the latter transition is associated with a deep alteration of the plastid genome. Photosynthesis-related genes are lost first, followed by housekeeping genes, eventually resulting in a highly reduced genome. Whether relaxation of selective constraints already occurs for the plastid genome of mixotrophic species, which remain photosynthetic, is unclear. This is partly due to the difficulty of comparing plastid genomes of autotrophic, mixotrophic and mycoheterotrophic species in a narrow phylogenetic framework. We address this question in the orchid tribe Neottieae, where this large assortment of nutrition types occurs. We sequenced 13 new plastid genomes, including nine mixotrophic species and covering all six Neottieae genera. We investigated selective pressure on plastid genes in each nutrition type and conducted a phylogenetic inference of the group. Surprisingly, photosynthesis-related genes did not experience selection relaxation in mixotrophic species compared to autotrophic relatives. Conversely, we observed evidence for selection intensification for some plastid genes. Photosynthesis is thus still under purifying selection, maybe because of its role in fruit formation and thus reproductive success. Phylogenetic analysis resolved most relationships, but short branches at the base of the tree suggest an evolutionary radiation at the beginning of Neottieae history, which, we hypothesize, may be linked to mixotrophy emergence.},
}
@article {pmid31396562,
year = {2019},
author = {Weizman, E and Levy, O},
title = {The role of chromatin dynamics under global warming response in the symbiotic coral model Aiptasia.},
journal = {Communications biology},
volume = {2},
number = {},
pages = {282},
doi = {10.1038/s42003-019-0543-y},
pmid = {31396562},
issn = {2399-3642},
abstract = {Extreme weather events frequency and scale are altered due to climate change. Symbiosis between corals and their endosymbiotic-dinoflagellates (Symbiodinium) is susceptible to these events and can lead to what is known as bleaching. However, there is evidence for coral adaptive plasticity in the role of epigenetic that have acclimated to high-temperature environments. We have implemented ATAC-seq and RNA-seq to study the cnidarian-dinoflagellate model Exaptasia pallida (Aiptasia) and expose the role of chromatin-dynamics in response to thermal-stress. We have identified 1309 genomic sites that change their accessibility in response to thermal changes. Moreover, apo-symbiotic Aiptasia accessible sites were enriched with NFAT, ATF4, GATA3, SOX14, and PAX3 motifs and expressed genes related to immunological pathways. Symbiotic Aiptasia accessible sites were enriched with NKx3-1, HNF4A, IRF4 motifs and expressed genes related to oxidative-stress pathways. Our work opens a new path towards understanding thermal-stress gene regulation in association with gene activity and chromatin-dynamics.},
}
@article {pmid31396243,
year = {2019},
author = {Romero-Munar, A and Baraza, E and Gulías, J and Cabot, C},
title = {Arbuscular Mycorrhizal Fungi Confer Salt Tolerance in Giant Reed (Arundo donax L.) Plants Grown Under Low Phosphorus by Reducing Leaf Na+ Concentration and Improving Phosphorus Use Efficiency.},
journal = {Frontiers in plant science},
volume = {10},
number = {},
pages = {843},
doi = {10.3389/fpls.2019.00843},
pmid = {31396243},
issn = {1664-462X},
abstract = {Salinization is one of the major causes of agricultural soil degradation worldwide. In arid and semi-arid regions with calcareous soils, phosphorus (P) deficiency further worsens the quality of salinized soils. Nonetheless, nutrient poor soils could be suitable of producing second-generation energy crops. Due to its high biomass production, Arundo donax L. (giant reed) is one of the most promising species for energy and second-generation biofuel production. A. donax can be propagated by micropropagation, an in vitro technique that produces high number of homogeneous plantlets. However, crop establishment is often compromised due to poor plantlet acclimatization to the soil environment. Arbuscular mycorrhizal fungi (AM) are components of soil-plant systems able to increase root phosphorus uptake and to confer the plant an increase tolerance to salinity with a consequent enhancement effect of plant growth and yield. In the present study, the relative importance of the early symbiosis establishment between AM fungi and A. donax micropropagated plantlets in the response to salt stress under low phosphorus availability was determined. A commercial inoculum which contained two different AM fungi species: Rhizophagus intraradices and Funneliformis mosseae was used. AM-symbionts (AM) and non-symbionts plants were grown at two phosphorus [2.5 μM (C) and 0.5 mM (P)] and three NaCl (1, 75 and 150 mM) concentrations in a room chamber under controlled conditions. After 5 weeks, AM root colonization was 60, 26 and 15% in 1, 75 and 150 mM NaCl-treated plants, respectively. At 1 and 75 mM NaCl, AM plants showed increased growth. In all saline treatments, AM plants had decreased Na+ uptake, Na+ root-to-shoot translocation, Na+/K+ ratio and increased P and K use efficiencies with respect to C and P plants. AM improved the nutritional status of A. donax plants by enhancing nutrient use efficiency rather than nutrient uptake. Increased phosphorus use efficiency in AM plants could have benefited ion (Na+ and K+) uptake and/or allocation and ultimately ameliorate the plant's response to saline conditions.},
}
@article {pmid31396178,
year = {2019},
author = {Trappeniers, K and Matetovici, I and Van Den Abbeele, J and De Vooght, L},
title = {The Tsetse Fly Displays an Attenuated Immune Response to Its Secondary Symbiont, Sodalis glossinidius.},
journal = {Frontiers in microbiology},
volume = {10},
number = {},
pages = {1650},
doi = {10.3389/fmicb.2019.01650},
pmid = {31396178},
issn = {1664-302X},
abstract = {Sodalis glossinidius, a vertically transmitted facultative symbiont of the tsetse fly, is a bacterium in the early/intermediate state of its transition toward symbiosis, representing an important model for investigating how the insect host immune defense response is regulated to allow endosymbionts to establish a chronic infection within their hosts without being eliminated. In this study, we report on the establishment of a tsetse fly line devoid of S. glossinidius only, allowing us to experimentally investigate (i) the complex immunological interactions between a single bacterial species and its host, (ii) how the symbiont population is kept under control, and (iii) the impact of the symbiont on the vector competence of the tsetse fly to transmit the sleeping sickness parasite. Comparative transcriptome analysis showed no difference in the expression of genes involved in innate immune processes between symbiont-harboring (GmmSod+) and S. glossinidius-free (GmmSod-) flies. Re-exposure of (GmmSod-) flies to the endosymbiotic bacterium resulted in a moderate immune response, whereas exposure to pathogenic E. coli or to a close non-insect associated relative of S. glossinidius, i.e., S. praecaptivus, resulted in full immune activation. We also showed that S. glossinidius densities are not affected by experimental activation or suppression of the host immune system, indicating that S. glossinidius is resistant to mounted immune attacks and that the host immune system does not play a major role in controlling S. glossinidius proliferation. Finally, we demonstrate that the absence or presence of S. glossinidius in the tsetse fly does not alter its capacity to mount an immune response to pathogens nor does it affect the fly's susceptibility toward trypanosome infection.},
}
@article {pmid31395953,
year = {2019},
author = {Cardini, U and Bartoli, M and Lücker, S and Mooshammer, M and Polzin, J and Lee, RW and Micić, V and Hofmann, T and Weber, M and Petersen, JM},
title = {Chemosymbiotic bivalves contribute to the nitrogen budget of seagrass ecosystems.},
journal = {The ISME journal},
volume = {},
number = {},
pages = {},
doi = {10.1038/s41396-019-0486-9},
pmid = {31395953},
issn = {1751-7370},
support = {VRG14-021//Vienna Science and Technology Fund (Wiener Wissenschafts-, Forschungs- und Technologiefonds)/ ; VRG14-021//Vienna Science and Technology Fund (Wiener Wissenschafts-, Forschungs- und Technologiefonds)/ ; 09.3.3-LMT-K-712-01-0069//Lietuvos Mokslo Taryba (Research Council of Lithuania)/ ; 09.3.3-LMT-K-712-01-0069//Lietuvos Mokslo Taryba (Research Council of Lithuania)/ ; },
abstract = {In many seagrass sediments, lucinid bivalves and their sulfur-oxidizing symbionts are thought to underpin key ecosystem functions, but little is known about their role in nutrient cycles, particularly nitrogen. We used natural stable isotopes, elemental analyses, and stable isotope probing to study the ecological stoichiometry of a lucinid symbiosis in spring and fall. Chemoautotrophy appeared to dominate in fall, when chemoautotrophic carbon fixation rates were up to one order of magnitude higher as compared with the spring, suggesting a flexible nutritional mutualism. In fall, an isotope pool dilution experiment revealed carbon limitation of the symbiosis and ammonium excretion rates up to tenfold higher compared with fluxes reported for nonsymbiotic marine bivalves. These results provide evidence that lucinid bivalves can contribute substantial amounts of ammonium to the ecosystem. Given the preference of seagrasses for this nitrogen source, lucinid bivalves' contribution may boost productivity of these important blue carbon ecosystems.},
}
@article {pmid31395464,
year = {2019},
author = {Payen, VL and Mina, E and Van Hée, VF and Porporato, PE and Sonveaux, P},
title = {Monocarboxylate transporters in cancer.},
journal = {Molecular metabolism},
volume = {},
number = {},
pages = {},
doi = {10.1016/j.molmet.2019.07.006},
pmid = {31395464},
issn = {2212-8778},
abstract = {BACKGROUND: Tumors are highly plastic metabolic entities composed of cancer and host cells that can adopt different metabolic phenotypes. For energy production, cancer cells may use 4 main fuels that are shuttled in 5 different metabolic pathways. Glucose fuels glycolysis that can be coupled to the tricarboxylic acid (TCA) cycle and oxidative phosphorylation (OXPHOS) in oxidative cancer cells or to lactic fermentation in proliferating and in hypoxic cancer cells. Lipids fuel lipolysis, glutamine fuels glutaminolysis, and lactate fuels the oxidative pathway of lactate, all of which are coupled to the TCA cycle and OXPHOS for energy production. This review focuses on the latter metabolic pathway.<br><br>SCOPE OF REVIEW: Lactate, which is prominently produced by glycolytic cells in tumors, was only recently recognized as a major fuel for oxidative cancer cells and as a signaling agent. Its exchanges across membranes are gated by monocarboxylate transporters MCT1-4. This review summarizes the current knowledge about MCT structure, regulation and functions in cancer, with a specific focus on lactate metabolism, lactate-induced angiogenesis and MCT-dependent cancer metastasis. It also describes lactate signaling via cell surface lactate receptor GPR81.<br><br>MAJOR CONCLUSIONS: Lactate and MCTs, especially MCT1 and MCT4, are important contributors to tumor aggressiveness. Analyses of MCT-deficient (MCT+/- and MCT-/-) animals and (MCT-mutated) humans indicate that they are druggable, with MCT1 inhibitors being in advanced development phase and MCT4 inhibitors still in the discovery phase. Imaging lactate fluxes non-invasively using a lactate tracer for positron emission tomography would further help to identify responders to the treatments.},
}
@article {pmid31393956,
year = {2019},
author = {Kokkoris, V and Hamel, C and Hart, MM},
title = {Mycorrhizal response in crop versus wild plants.},
journal = {PloS one},
volume = {14},
number = {8},
pages = {e0221037},
doi = {10.1371/journal.pone.0221037},
pmid = {31393956},
issn = {1932-6203},
abstract = {We proposed a theoretical framework predicting mutualistic outcomes for the arbuscular mycorrhizal (AM) symbiosis based on host provenance (crop versus wild). To test the framework, we grew two isolates of Rhizoglomus irregulare (commercial versus an isolate locally isolated), with five crop plants and five wild plants endemic to the region that co-occur with the locally sourced fungus. While inoculation with either isolate had no effect on plant biomass, it decreased leaf P content, particularly for wild plants. All plants associating with the commercial fungus had lower leaf P. Overall, our data shows that wild plants may be more sensitive to differences in mutualistic quality among fungal isolates.},
}
@article {pmid31392918,
year = {2019},
author = {Buendia, L and Ribeyre, C and Bensmihen, S and Lefebvre, B},
title = {Brachypodium distachyon tar2lhypo mutant shows reduced root developmental response to symbiotic signal but increased arbuscular mycorrhiza.},
journal = {Plant signaling &amp; behavior},
volume = {},
number = {},
pages = {1-3},
doi = {10.1080/15592324.2019.1651608},
pmid = {31392918},
issn = {1559-2324},
abstract = {Auxin is a major phytohormone that controls root development. A role for auxin is also emerging in the control of plant-microbe interactions, including for the establishment of root endosymbiosis between plants and arbuscular mycorrhizal fungi (AMF). Auxin perception is important both for root colonization by AMF and for arbuscule formation. AMF produce symbiotic signals called lipo-chitooligosaccharides (LCOs) that can modify auxin homeostasis and promote lateral root formation (LRF). Since Brachypodium distachyon (Brachypodium) has a different auxin sensitivity compared to other plant species, we wondered whether this would interfere with the effect of auxin in arbuscular mycorrhizal (AM) symbiosis. Here we tested whether tar2lhypo a Brachypodium mutant with an increase in endogenous auxin content is affected in LRF stimulation by LCOs and in AM symbiosis. We found that, in contrast to control plants, LCO treatment inhibited LRF of the tar2lhypo mutant. However, the level of AMF colonization and the abundance of arbuscules were increased in tar2lhypo compared to control plants, suggesting that auxin also plays a positive role in both AMF colonization and arbuscule formation in Brachypodium.},
}
@article {pmid31389400,
year = {2019},
author = {Kavadi, SN},
title = {The founding of the Tata Memorial Hospital, 1932-1941.},
journal = {Indian journal of cancer},
volume = {56},
number = {3},
pages = {282-284},
doi = {10.4103/ijc.IJC_13_19},
pmid = {31389400},
issn = {1998-4774},
abstract = {This article presents a brief account of the founding of the Tata Memorial Hospital. It draws upon archival material to show that this was not a mere philanthropic act but a scheme carefully thought-out by the Trustees of the Sir Dorabji Tata Trust. It discusses the major concerns of the Trustees as they deliberated upon establishing the Hospital.},
}
@article {pmid31388025,
year = {2019},
author = {Lanzoni, O and Plotnikov, A and Khlopko, Y and Munz, G and Petroni, G and Potekhin, A},
title = {The core microbiome of sessile ciliate Stentor coeruleus is not shaped by the environment.},
journal = {Scientific reports},
volume = {9},
number = {1},
pages = {11356},
doi = {10.1038/s41598-019-47701-8},
pmid = {31388025},
issn = {2045-2322},
support = {295176//EC | EC Seventh Framework Programm | FP7 People: Marie-Curie Actions (FP7-PEOPLE - Specific Programme &amp;quot;People&amp;quot; Implementing the Seventh Framework Programme of the European Community for Research, Technological Development and Demonstration Activities (2007 to 2013))/ ; 16-14-10157//Russian Science Foundation (RSF)/ ; },
abstract = {Microbiomes of multicellular organisms are one of the hottest topics in microbiology and physiology, while only few studies addressed bacterial communities associated with protists. Protists are widespread in all environments and can be colonized by plethora of different bacteria, including also human pathogens. The aim of this study was to characterize the prokaryotic community associated with the sessile ciliate Stentor coeruleus. 16S rRNA gene metabarcoding was performed on single cells of S. coeruleus and on their environment, water from the sewage stream. Our results showed that the prokaryotic community composition differed significantly between Stentor cells and their environment. The core microbiome common for all ciliate specimens analyzed could be defined, and it was composed mainly by representatives of bacterial genera which include also potential human pathogens and commensals, such as Neisseria, Streptococcus, Capnocytophaga, Porphyromonas. Numerous 16S rRNA gene contigs belonged to endosymbiont &quot;Candidatus Megaira polyxenophila&quot;. Our data suggest that each ciliate cell can be considered as an ecological microniche harboring diverse prokaryotic organisms. Possible benefits for persistence and transmission in nature for bacteria associated with protists are discussed. Our results support the hypothesis that ciliates attract potentially pathogenic bacteria and play the role of natural reservoirs for them.},
}
@article {pmid31386172,
year = {2019},
author = {David, AS and Bell-Dereske, LP and Emery, SM and McCormick, BM and Seabloom, EW and Rudgers, JA},
title = {Testing for loss of Epichloë and non-epichloid symbionts under altered rainfall regimes.},
journal = {American journal of botany},
volume = {106},
number = {8},
pages = {1081-1089},
doi = {10.1002/ajb2.1340},
pmid = {31386172},
issn = {1537-2197},
support = {DEB 0918267//NSF/ ; DEB 1145588//NSF/ ; NSF 0940902//NSF/ ; DGE-0653827//NSF/ ; NSF 00039202//NSF/ ; },
abstract = {PREMISE: Microbial symbionts can buffer plant hosts from environmental change. Therefore, understanding how global change factors alter the associations between hosts and their microbial symbionts may improve predictions of future changes in host population dynamics and microbial diversity. Here, we investigated how one global change factor, precipitation, affected the maintenance or loss of symbiotic fungal endophytes in a C3 grass host. Specifically, we examined the distinct responses of Epichloë (vertically transmitted and systemic) and non-epichloid endophytes (typically horizontally transmitted and localized) by considering (1) how precipitation altered associations with Epichloë and non-epichloid endophytic taxa across host ontogeny, and (2) interactive effects of water availability and Epichloë on early seedling life history stages.<br><br>METHODS: We manipulated the presence of Epichloë amarillans in American beachgrass (Ammophila breviligulata) in a multiyear field experiment that imposed three precipitation regimes (ambient or ±30% rainfall). In laboratory assays, we investigated the interactive effects of water availability and Epichloë on seed viability and germination.<br><br>RESULTS: Reduced precipitation decreased the incidence of Epichloë in leaves in the final sampling period, but had no effect on associations with non-epichloid taxa. Epichloë reduced the incidence of non-epichloid endophytes, including systemic p-endophytes, in seeds. Laboratory assays suggested that association with Epichloë is likely maintained, in part, due to increased seed viability and germination regardless of water availability.<br><br>CONCLUSIONS: Our study empirically demonstrates several pathways for plant symbionts to be lost or maintained across host ontogeny and suggests that reductions in precipitation can drive the loss of a plant's microbial symbionts.},
}
@article {pmid31382604,
year = {2019},
author = {Nobre, T},
title = {Symbiosis in Sustainable Agriculture: Can Olive Fruit Fly Bacterial Microbiome Be Useful in Pest Management?.},
journal = {Microorganisms},
volume = {7},
number = {8},
pages = {},
doi = {10.3390/microorganisms7080238},
pmid = {31382604},
issn = {2076-2607},
support = {PTDC/ASP-PLA/30650/2017//Fundação para a Ciência e a Tecnologia/ ; },
abstract = {The applied importance of symbiosis has been gaining recognition. The relevance of symbiosis has been increasing in agriculture, in developing sustainable practices, including pest management. Insect symbiotic microorganisms' taxonomical and functional diversity is high, and so is the potential of manipulation of these microbial partners in suppressing pest populations. These strategies, which rely on functional organisms inhabiting the insect, are intrinsically less susceptible to external environmental variations and hence likely to overcome some of the challenges posed by climate change. Rates of climate change in the Mediterranean Basin are expected to exceed global trends for most variables, and this warming will also affect olive production and impact the interactions of olives and their main pest, the obligate olive fruit fly (Bactroceraoleae). This work summarizes the current knowledge on olive fly symbiotic bacteria towards the potential development of symbiosis-based strategies for olive fruit fly control. Particular emphasis is given to Candidatus Erwinia dacicola, an obligate, vertically transmitted endosymbiont that allows the insect to cope with the olive-plant produced defensive compound oleuropein, as a most promising target for a symbiosis disruption approach.},
}
@article {pmid31380084,
year = {2019},
author = {Yoshida, K and Sanada-Morimura, S and Huang, SH and Tokuda, M},
title = {Influences of two coexisting endosymbionts, CI-inducing Wolbachia and male-killing Spiroplasma, on the performance of their host Laodelphax striatellus (Hemiptera: Delphacidae).},
journal = {Ecology and evolution},
volume = {9},
number = {14},
pages = {8214-8224},
doi = {10.1002/ece3.5392},
pmid = {31380084},
issn = {2045-7758},
abstract = {The small brown planthopper Laodelphax striatellus (Hemiptera: Delphacidae) is reported to have the endosymbiont Wolbachia, which shows a strong cytoplasmic incompatibility (CI) between infected males and uninfected females. In the 2000s, female-biased L. striatellus populations were found in Taiwan, and this sex ratio distortion was the result of male-killing induced by the infection of another endosymbiont, Spiroplasma. Spiroplasma infection is considered to negatively affect both L. striatellus and Wolbachia because the male-killing halves the offspring of L. striatellus and hinders the spread of Wolbachia infection via CI. Spiroplasma could have traits that increase the fitness of infected L. striatellus and/or coexisting organisms because the coinfection rates of Wolbachia and Spiroplasma were rather high in some areas. In this study, we investigated the influences of the infection of these two endosymbionts on the development, reproduction, and insecticide resistance of L. striatellus in the laboratory. Our results show that the single-infection state of Spiroplasma had a negative influence on the fertility of L. striatellus, while the double-infection state had no significant influence. At late nymphal and adult stages, the abundance of Spiroplasma was lower in the double-infection state than in the single-infection state. In the double-infection state, the reduction of Spiroplasma density may be caused by competition between the two endosymbionts, and the negative influence of Spiroplasma on the fertility of host may be relieved. The resistance of L. striatellus to four insecticides was compared among different infection states of endosymbionts, but Spiroplasma infection did not contribute to increase insecticide resistance. Because positive influences of Spiroplasma infection were not found in terms of the development, reproduction, and insecticide resistance of L. striatellus, other factors improving the fitness of Spiroplasma-infected L. striatellus may be related to the high frequency of double infection in some L. striatellus populations.},
}
@article {pmid31380028,
year = {2019},
author = {Bromfield, ESP and Cloutier, S and Robidas, C and Tran Thi, TV and Darbyshire, SJ},
title = {Invasive Galega officinalis (Goat's rue) plants in Canada form a symbiotic association with strains of Neorhizobium galegae sv. officinalis originating from the Old World.},
journal = {Ecology and evolution},
volume = {9},
number = {12},
pages = {6999-7004},
doi = {10.1002/ece3.5266},
pmid = {31380028},
issn = {2045-7758},
abstract = {The toxic legume plant, Galega officinalis, is native to the Eastern Mediterranean and Black Sea regions. This legume is considered to be a noxious weed, and its establishment in Canada may have resulted from ornamental planting and/or field trials. In its native range, a highly specific nitrogen-fixing symbiosis with the bacterium, Neorhizobium galegae symbiovar (sv.) officinalis, is required for normal growth. In North America, nothing is known about the bacterial symbionts of G. officinalis. Our purpose was to determine the species and symbiovar identity of symbiotic bacteria associated with invasive plants of G. officinalis at five sites in the province of Ontario, Canada. Sequence analysis of four housekeeping (16S rRNA, atpD, glnII, and recA) and two symbiosis (nodC and nifH) genes showed that all 50 bacterial isolates from root nodules of G. officinalis at the five Canadian sites were identical to strains of N. galegae sv. officinalis originating either from Europe or the Caucasus. Plant tests indicated that soils collected from four Canadian sites without a history of agriculture or presence of G. officinalis were deficient in symbiotic bacteria capable of eliciting nodules on this plant. Collectively our data support the hypothesis of anthropogenic co-introduction of G. officinalis and its specific symbiotic bacterium into Canada from the Old World. Factors that may limit the spread of G. officinalis in new environments are discussed.},
}
@article {pmid31377982,
year = {2019},
author = {González, CT and Saltonstall, K and Fernández-Marín, H},
title = {Garden microbiomes of Apterostigma dentigerum and Apterostigma pilosum fungus-growing ants (Hymenoptera: Formicidae).},
journal = {Journal of microbiology (Seoul, Korea)},
volume = {},
number = {},
pages = {},
doi = {10.1007/s12275-019-8639-0},
pmid = {31377982},
issn = {1976-3794},
abstract = {Fungus-growing ants share a complex symbiosis with microbes, including fungal mutualists, antibiotic-producing bacteria, and fungal pathogens. The bacterial communities associated with this symbiosis are poorly understood but likely play important roles in maintaining the health and function of fungal gardens. We studied bacterial communities in gardens of two Apterostigma species, A. dentigerum, and A. pilosum, using next-generation sequencing to evaluate differences between the two ant species, their veiled and no-veiled fungal garden types, and across three collection locations. We also compared different parts of nests to test for homogeneity within nests. Enterobacteriaceae dominated gardens of both species and common OTUs were shared across both species and nest types. However, differences in community diversity were detected between ant species, and in the communities of A. dentigerum veiled and no-veiled nests within sites. Apterostigma pilosum had a higher proportion of Phyllo-bacteriaceae and differed from A. dentigerum in the proportions of members of the order Clostridiales. Within A. dentigerum, nests with veiled and no-veiled fungus gardens had similar taxonomic profiles but differed in the relative abundance of some groups, with veiled gardens having more Rhodospirillaceae and Hyphomicrobiaceae, and no-veiled having more Xanthomonadaceae and certain genera in the Enter-obacteriaceae C. However, bacterial communities in Apterostigma fungal gardens are highly conserved and resemble those of the nests of other attine ants with dominant taxa likely playing a role in biomass degradation and defense. Further work is required to understand and explain how bacterial community composition of fungus-growing nests is maintained.},
}
@article {pmid31377102,
year = {2019},
author = {Bailey, GF and Bilsky, AM and Rowland, MB and Poole, AZ},
title = {Characterization and expression of tyrosinase-like genes in the anemone Exaiptasia pallida as a function of health and symbiotic state.},
journal = {Developmental and comparative immunology},
volume = {101},
number = {},
pages = {103459},
doi = {10.1016/j.dci.2019.103459},
pmid = {31377102},
issn = {1879-0089},
abstract = {Coral disease is a major threat to reef ecosystems and therefore, understanding the cellular pathways underlying disease progression and resistance is critical to mitigating future outbreaks. This study focused on tyrosinase-like proteins in cnidarians, which contribute to melanin synthesis, an invertebrate innate immune defense. Specifically, characterization and phylogenetic analysis of cnidarian tyrosinases were performed, and their role in symbiosis and a &quot;mystery disease&quot; in the anemone Exaiptasia pallida was investigated using qPCR. The results reveal a diversity of tyrosinase-like proteins in cnidarians that separate into two major clades on a phylogenetic tree, suggesting functional divergence. Two E. pallida sequences, Ep_Tyr1 and Ep_Tyr2, were further investigated, and qPCR results revealed no gene expression differences as a function of symbiotic state, but decreased expression in late disease stages. Overall this work provides evidence for the participation of tyrosinases in the cnidarian immune response.},
}
@article {pmid31375484,
year = {2019},
author = {Sun, YW and Li, Y and Hu, Y and Chen, WX and Tian, CF},
title = {Coordinated regulation of size and number of PHB granules by core and accessory phasins in the facultative microsymbiont Sinorhizobium fredii NGR234.},
journal = {Applied and environmental microbiology},
volume = {},
number = {},
pages = {},
doi = {10.1128/AEM.00717-19},
pmid = {31375484},
issn = {1098-5336},
abstract = {The exact roles of various granule-associated proteins (GAPs) of polyhydroxybutyrate (PHB) are poorly investigated particularly in bacteria associated with plants. Here, four structural GAPs, named as phasins PhaP1-PhaP4, were identified and demonstrated as true phasins colocalized with PHB granules in Sinorhizobium fredii NGR234, a facultative microsymbiont of Vigna unguiculata and many other legumes. The conserved PhaP2 dominated in regulation of granule size under both free-living and symbiotic conditions. PhaP1, another conserved phasin, made a higher contribution than accessory PhaP4 and PhaP3 to PHB biosynthesis at stationary phase. PhaP3, with limited phyletic distribution on the symbiosis plasmid of Sinorhizobium, was more important than PhaP1 in regulating PHB biosynthesis in V. unguiculata nodules. In the test conditions, no significant symbiotic defects were observed for mutants lacking individual or multiple phaP genes. The mutant lacking two PHB synthases showed impaired symbiotic performance while mutations in individual PHB synthases or a PHB depolymerase had no symbiotic defects. This phenomenon is not related to either the number or size of PHB granules in test mutants within nodules. Distinct metabolic profiles and cocktail pools of GAPs of different phaP(s) mutants imply that core and accessory phasins can be differentially involved in regulating other cellular process in the facultative microsymbiont S. fredii NGR234.Importance Polyhydroxybutyrate (PHB) granules are a store of carbon and energy in bacteria and archaea, and play an important role in stress adaptation. Recent studies have highlighted distinct roles of several granule-associated proteins (GAPs) in regulating the size, number and localization of PHB granules in free-living bacteria, though our knowledge on the role of GAPs in bacteria associated with plants is still limited. Here we report distinct roles of core and accessory phasins associated with PHB granules of Sinorhizobium fredii NGR234, a broad host range microsymbiont of diverse legumes. Core phasins PhaP2 and PhaP1 are conserved major phasins in free living cells. PhaP2 and an accessory phasin PhaP3 encoded by an auxiliary gene on the symbiosis plasmid are major phasins in nitrogen fixing bacteroids in cowpea nodules. GAPs and metabolic profiles can vary in different phaP mutants. Contrasting symbiotic performance between mutants lacking PHB synthases, depolymerase or phasins were revealed.},
}
@article {pmid31373013,
year = {2019},
author = {Zhang, W and Yuan, J and Cheng, T and Tang, MJ and Sun, K and Song, SL and Xu, FJ and Dai, CC},
title = {Flowering-mediated root-fungus symbiosis loss is related to jasmonate-dependent root soluble sugar deprivation.},
journal = {Plant, cell &amp; environment},
volume = {},
number = {},
pages = {},
doi = {10.1111/pce.13636},
pmid = {31373013},
issn = {1365-3040},
support = {NSFC 31870478//National Natural Science Foundation of China/ ; //Priority Academic Program Development (PAPD) of Jiangsu Higher Education Institutions of China/ ; 1812000006317//Doctor Breeding Project of Nanjing Normal University/ ; },
abstract = {The role of flowering in root-fungal symbiosis is not well understood. Because flowering and fungal symbionts are supported by carbohydrates, we hypothesized that flowering modulates root-beneficial fungal associations through alterations in carbohydrate metabolism and transport. We monitored fungal colonization and soluble sugars in the roots of Arabidopsis thaliana following inoculation with a mutualistic fungus Phomopsis liquidambari across different plant developmental stages. Jasmonate signalling of wild-type plants, sugar transport, and root invertase of wild-type and jasmonate-insensitive plants were exploited to assess whether and how jasmonate-dependent sugar dynamics are involved in flowering-mediated fungal colonization alterations. We found that flowering restricts root-fungal colonization and activates root jasmonate signalling upon fungal inoculation. Jasmonates reduce the constitutive and fungus-induced accumulation of root glucose and fructose at the flowering stage. Further experiments with sugar transport and metabolism mutant lines revealed that root glucose and fructose positively influence fungal colonization. Diurnal, jasmonate-dependent inhibitions of sugar transport and soluble invertase activity were identified as likely mechanisms for flowering-mediated root sugar depletion upon fungal inoculation. Collectively, our results reveal that flowering drives root-fungus cooperation loss, which is related to jasmonate-dependent root soluble sugar depletion. Limiting the spread of root-fungal colonization may direct more resources to flower development.},
}
@article {pmid31372335,
year = {2019},
author = {McElwain, A and Warren, MB and Pereira, FB and Ksepka, SP and Bullard, SA},
title = {Pathobiology and first report of larval nematodes (Ascaridomorpha sp.) infecting freshwater mussels (Villosa nebulosa, Unionidae), including an inventory of nematode infections in freshwater and marine bivalves.},
journal = {International journal for parasitology. Parasites and wildlife},
volume = {10},
number = {},
pages = {41-58},
doi = {10.1016/j.ijppaw.2019.05.006},
pmid = {31372335},
issn = {2213-2244},
abstract = {Little information is available on host-parasite relationships between bivalves and larval nematodes. Herein, we describe nematode larvae (likely stage 2) in the infraorder Ascaridomorpha infecting the foot, intestine, and mantle of a freshwater mussel (Alabama rainbow, Villosa nebulosa [Conrad, 1834]) and detail histopathological changes to infected tissues. A total of 43 live mussels from the South Fork of Terrapin Creek, Alabama, were collected between 2010 and 2014, with 14 sectioned for histopathology and 29 dissected. Of the 14 sectioned mussels, 5 appeared to be uninfected, and 7, 1, and 1 had histozoic infections observed in the foot and intestine, intestine only, and mantle edge and foot, respectively. Twenty-three of 29 (79%) of the mussels dissected were infected by live nematodes, and mean nematode abundance was 8.3 (CL = 5.23-13), with 2 mussels infected with >100 nematodes each. Thus, with a total of 32 of the 43 collected mussels observed with nematodes, overall infection prevalence was 74.4% (CL = 0.594-0.855). The 18S rDNA of this nematode was 99% similar to that of several ascaridids (species of Kathlaniidae Lane, 1914 and Quimperiidae Baylis, 1930) that mature in aquatic/semi-aquatic vertebrates; the recovered 18S phylogenetic tree indicated this nematode from V. nebulosa shares a recent common ancestor with Ichthyobronema hamulatum (Ascaridomorpha: Quimperiidae; GenBank Accession Number KY476351). Pathological changes to tissue associated with these infections comprised focal tissue damage, but a cellular response was not evident. The Alabama rainbow possibly represents an intermediate or paratenic host. Given these results, the nematode is likely not pathogenic under normal stream conditions; however, high intensity infections in the foot could inhibit pedal extension and retraction; which would have demonstrable health consequences to a freshwater mussel. Based on our review of the bivalve mollusc parasite literature, a collective biodiversity of 61 nematodes reportedly exhibit some degree of symbiosis (from commensal to parasitic) with 21 bivalves (28 nematode spp. from 17 marine bivalve spp.; 33 nematode spp. from 4 freshwater bivalve spp.); only four records exist of putatively parasitic nematodes from Unionida. The present study represents the first description of a nematode species that invades the tissues of a Unionidae species.},
}
@article {pmid31371739,
year = {2019},
author = {Ullah, I and Magdy, M and Wang, L and Liu, M and Li, X},
title = {Genome-wide identification and evolutionary analysis of TGA transcription factors in soybean.},
journal = {Scientific reports},
volume = {9},
number = {1},
pages = {11186},
doi = {10.1038/s41598-019-47316-z},
pmid = {31371739},
issn = {2045-2322},
support = {31730066//National Natural Science Foundation of China (National Science Foundation of China)/ ; },
abstract = {The gain of function in genes and gene families is a continuous process and is a key factor in understanding gene and genome evolution in plants. TGACG-Binding (TGA) transcription factors (TFs) have long been known for their essential roles in plant defence in Arabidopsis, but their roles in legume symbiosis are yet to be explored. Here, we identified a total of 25 TGA (named GmTGA1-GmTGA25) genes in soybean. Through phylogenetic analysis, we discovered a clade of GmTGA proteins that appear to be legume-specific. Among them, two GmTGAs were unique by possessing the autophagy sequence in their proteins, while the third one was an orphan gene in soybean. GmTGAs were structurally different from AtTGAs, and their expression patterns also differed with the dominant expression of AtTGAs and GmTGAs in aerial and underground parts, respectively. Moreover, twenty-five GmTGAs showed a strong correlation among the gene expression in roots, nodules, and root hairs. The qRT-PCR analysis results revealed that among 15 tested GmTGAs, six were induced and four were suppressed by rhizobia inoculation, while 11 of these GmTGAs were induced by high nitrate. Our findings suggested the important roles of GmTGAs in symbiotic nodulation and in response to nitrogen availability in soybean.},
}
@article {pmid31368540,
year = {2019},
author = {Pereira, J and Simões, M and Silva, JL},
title = {Microalgal assimilation of vitamin B12 toward the production of a superfood.},
journal = {Journal of food biochemistry},
volume = {43},
number = {8},
pages = {e12911},
doi = {10.1111/jfbc.12911},
pmid = {31368540},
issn = {1745-4514},
abstract = {A network of components from different metabolic pathways is the building scaffold of an indispensable compound in the human organism-vitamin B12 . The biosynthesis of this compound is restricted to a limited number of representatives of bacteria and archaea, while vitamin B12 -dependent enzymes are spread through several domains of life. Different attempts have been performed to increase vitamin B12 levels in dietary products, particularly in vegetarian and vegan dietary regimes. The integration of vitamin B12 in microalgae through symbiosis with microorganisms generally recognized as safe, for example the probiotic Lactobacillus reuteri, can even increase the nutritional value of the microalgal biomass. This study reviews the microbial production of vitamin B12 based on genetic analyses and chemical studies. Recent genetic approaches are focused, particularly potential metabolic engineering targets to increase vitamin B12 production. The bioincorporation of vitamin B12 in microalgae as an attempt to provide a superfood is also reviewed. PRACTICAL APPLICATIONS: Novel food habits (i.e., vegan lifestyle) may lack relevant nutrients, including vitamin B12 . Therefore, there is an increased demand for dietary products rich in vitamin B12 . Of potential interest is the provision of microbial-based superfood rich in numerous nutrients, including this vitamin. This manuscript provides an in-depth and timely overview on vitamin B12 biosynthesis and the major advances on metabolic engineering for improved vitamin B12 production by probiotic bacteria and other microorganisms generally recognized as safe. A relevant advance would result from the bioincorporation of vitamin B12 in alternative microorganisms (non-vitamin B12 producers) increasingly recognized as superfood, that is microalgae.},
}
@article {pmid31359038,
year = {2019},
author = {Kashkouli, M and Fathipour, Y and Mehrabadi, M},
title = {Heritable Gammaproteobacterial Symbiont Improves the Fitness of Brachynema germari Kolenati (Hemiptera: Pentatomidae).},
journal = {Environmental entomology},
volume = {},
number = {},
pages = {},
doi = {10.1093/ee/nvz089},
pmid = {31359038},
issn = {1938-2936},
abstract = {The pistachio green stink bug, Brachynema germari Kolenati, is an abundant and economic insect pest in most pistachio-growing regions. Some physiological and ecological features of this pest have been studied, but the microbiological nature of symbiotic bacteria and biological aspects of this host-symbiont interaction have been poorly understood. In the present study, we explored the host-associated environment, phylogeny, and acquisition features of the bacterial symbiont of the insect. Furthermore, the importance of the symbiont on the biological (i.e., lifespan, stage composition, and body weight) and behavioral characteristics (i.e., resting/wandering behaviors of the newborn nymphs) of the host were investigated. We found that a rod-shaped gammaproteobacterium was persistently colonized the fourth midgut region of the insect. Molecular phylogenetic and fluorescence in situ hybridization analyses strongly suggest that this symbiont should be placed in the genus Pantoea of the Enterobacteriales. Egg surface sterilization resulted in the aposymbiotic insects suggesting the vertical transmission of symbiont via egg surface smearing upon oviposition. Symbiotic and aposymbiotic B. germari showed no significant differences in the wandering behaviors of the first nymphal stages, whereas the symbiont-free insects exhibited retarded growth, lower longevity, and adult body weight. Taken together, these data provide a better understanding of the relationship between the bacterial symbiont and B. germari and demonstrate that the insect is heavily affected by the deprival of its gut symbionts.},
}
@article {pmid31354772,
year = {2019},
author = {Li, X and He, XL and Zhou, Y and Hou, YT and Zuo, YL},
title = {Effects of Dark Septate Endophytes on the Performance of Hedysarum scoparium Under Water Deficit Stress.},
journal = {Frontiers in plant science},
volume = {10},
number = {},
pages = {903},
doi = {10.3389/fpls.2019.00903},
pmid = {31354772},
issn = {1664-462X},
abstract = {Hedysarum scoparium, a species characterized by rapid growth and high drought resistance, has been used widely for vegetative restoration of arid regions in Northwest China that are prone to desertification. Desert soil is typically deficient in available water and the alleviation of drought stress to host plants by endophytes could be an efficient strategy to increase the success of desert restoration. With the objective to seek more beneficial symbionts that can be used in the revegetation strategies, we addressed the question whether H. scoparium can benefit from inoculation by dark septate endophytes (DSEs) isolated from other desert plants. We investigated the influences of four non-host DSE strains (Phialophora sp., Knufia sp., Leptosphaeria sp., and Embellisia chlamydospora) isolated from other desert plants on the performance of H. scoparium under different soil water conditions. Differences in plant performance, such as plant growth, antioxidant enzyme activities, carbon, nitrogen, and phosphorous concentration under all the treatments, were examined. Four DSE strains could colonize the roots of H. scoparium successfully, and they established a positive symbiosis with the host plants depending on DSE species and water availability. The greatest benefits of DSE inoculation occurred in water stress treatment. Specifically, Phialophora sp. and Leptosphaeria sp. improved the root biomass, total biomass, nutrient concentration, and antioxidant enzyme activities of host plants under water deficit conditions. These data contribute to the understanding of the ecological function of DSE fungi in drylands.},
}
@article {pmid31354767,
year = {2019},
author = {Wilkinson, TDJ and Miranda, JP and Ferrari, J and Hartley, SE and Hodge, A},
title = {Aphids Influence Soil Fungal Communities in Conventional Agricultural Systems.},
journal = {Frontiers in plant science},
volume = {10},
number = {},
pages = {895},
doi = {10.3389/fpls.2019.00895},
pmid = {31354767},
issn = {1664-462X},
abstract = {Arbuscular mycorrhizal fungi (AMF) form symbioses with the roots of most plant species, including cereals. AMF can increase the uptake of nutrients including nitrogen (N) and phosphorus (P), and of silicon (Si) as well as increase host resistance to various stresses. Plants can simultaneously interact with above-ground insect herbivores such as aphids, which can alter the proportion of plant roots colonized by AMF. However, it is unknown if aphids impact the structure of AMF communities colonizing plants or the extent of the extraradical mycelium produced in the soil, both of which can influence the defensive and nutritional benefit a plant derives from the symbiosis. This study investigated the effect of aphids on the plant-AMF interaction in a conventionally managed agricultural system. As plants also interact with other soil fungi, the non-AMF fungal community was also investigated. We hypothesized that aphids would depress plant growth, and reduce intraradical AMF colonization, soil fungal hyphal density and the diversity of AM and non-AM fungal communities. To test the effects of aphids, field plots of barley enclosed with insect proof cages were inoculated with Sitobion avenae or remained uninoculated. AMF specific and total fungal amplicon sequencing assessed root fungal communities 46 days after aphid addition. Aphids did not impact above-ground plant biomass, but did increase the grain N:P ratio. Whilst aphid presence had no impact on AMF intraradical colonization, soil fungal hyphal length density, or AMF community characteristics, there was a trend for the aphid treatment to increase vesicle numbers and the relative abundance of the AMF family Gigasporaceae. Contrary to expectations, the aphid treatment also increased the evenness of the total fungal community. This suggests that aphids can influence soil communities in conventional arable systems, a result that could have implications for multitrophic feedback loops between crop pests and soil organisms across the above-below-ground interface.},
}
@article {pmid31352211,
year = {2019},
author = {Xu, H and Shao, H and Lu, Y},
title = {Arbuscular mycorrhiza fungi and related soil microbial activity drive carbon mineralization in the maize rhizosphere.},
journal = {Ecotoxicology and environmental safety},
volume = {182},
number = {},
pages = {109476},
doi = {10.1016/j.ecoenv.2019.109476},
pmid = {31352211},
issn = {1090-2414},
abstract = {This research is aimed to investigate the effect of arbuscular mycorrhiza (AM) fungi on soil microbial activity and carbon mineralization in the maize rhizosphere under potted condition. Glomus etunicatum was used for our experiment. Results showed that AM symbiosis increased the levels of microorganism in the maize rhizosphere soil, and enhanced activity of soil microbial enzymes. After inoculating AM fungi, the contents of dissolved organic carbon (DOC), microbial biomass carbon (MBC) and readily oxidizable carbon (ROC) in the rhizosphere soil of maize increased with varying degrees. We obtained strong evidence that higher contents of MBC, DOC, ROC, superior number of microbes and stronger soil enzyme activities could be responsible for the higher rate of carbon mineralization in AM fungi treatment. AM fungi inoculation was confirmed to be effective to improve the soil quality for larger-scale ecoengineering.},
}
@article {pmid31351601,
year = {2019},
author = {Antoniou, NA and Zorpas, AA},
title = {Quality protocol and procedure development to define end-of-waste criteria for tire pyrolysis oil in the framework of circular economy strategy.},
journal = {Waste management (New York, N.Y.)},
volume = {95},
number = {},
pages = {161-170},
doi = {10.1016/j.wasman.2019.05.035},
pmid = {31351601},
issn = {1879-2456},
abstract = {The requirements to define End-of-Waste Criteria (EWC) were set in the Waste Framework Directive (WFD), Article 6 and the detailed data collected are considered to be the baseline for the elaboration of the operational EWC through several steps. Such waste stream (which is produced from End of Life Tires-ELT) could be a valuable source for energy recovery and can be used on a pan-European basis as an alternative fuel, for co-incineration in cement plants or furthermore in internal compunctions engines. The exploration for sustainable energy is one of the most dynamic areas of research currently. This study aims to investigate the ability to manage and exploit the energy content of Tire Pyrolysis Oil (TPO), through pyrolysis technology as incineration/co-incineration technology for ELTs presents significant environmental issues. However, TPO, must be declassified from waste in order to be able to be use as an alternative fuel in internal combustion engines for power generation participating in the loop of circular economy and industrial symbiosis. This paper focus on the development of a Quality Protocol (QP) and the procedure how to develop EWC for the declassification of TPO in order to replace Light Fuel Oil (LFO).},
}
@article {pmid31347943,
year = {2019},
author = {Sarsaiya, S and Shi, J and Chen, J},
title = {A comprehensive review on fungal endophytes and its dynamics on Orchidaceae plants: current research, challenges, and future possibilities.},
journal = {Bioengineered},
volume = {10},
number = {1},
pages = {316-334},
doi = {10.1080/21655979.2019.1644854},
pmid = {31347943},
issn = {2165-5987},
mesh = {Biological Products/*chemistry/isolation &amp; purification ; Endophytes/classification/genetics/*metabolism ; Fungi/classification/genetics/*metabolism ; Metabolic Networks and Pathways/physiology ; Orchidaceae/*microbiology ; Plant Leaves/microbiology ; Plant Roots/microbiology ; Plant Stems/microbiology ; Secondary Metabolism/physiology ; Symbiosis/*physiology ; },
abstract = {In the development of medicinally important Orchidaceae, the extent of fungal endophytes specificity is not presently very clear. Limited study has been available on natural products formed and its role on plant growth, defence mechanism by endophytes, and to characterize the chief treasure of bioactive molecules. Therefore, this review article presents an evaluation of the endophytes associated with Orchidaceae for physiology, metabolism, and genomics which have prominently contributed to the resurgence of novel metabolite research increasing our considerate of multifaceted mechanisms regulatory appearance of biosynthetic gene groups encoding diverse metabolites. Additionally, we presented the comprehensive recent development of bio-strategies for the cultivation of endophytes from Orchidaceae and integration of bioengineered 'Genomics with metabolism' approaches with emphases collective omics as powerful approach to discover novel metabolite compounds. The Orchidaceae-fungal endophytes' biodynamics for sustainable development of bioproducts and its applications are supported in large-scale biosynthesis of industrially and pharmaceutical important biomolecules.},
}
@article {pmid31346602,
year = {2019},
author = {Petersen, G and Darby, H and Lam, VKY and Pedersen, HÆ and Merckx, VSFT and Zervas, A and Seberg, O and Graham, SW},
title = {Mycoheterotrophic Epirixanthes (Polygalaceae) has a typical angiosperm mitogenome but unorthodox plastid genomes.},
journal = {Annals of botany},
volume = {},
number = {},
pages = {},
doi = {10.1093/aob/mcz114},
pmid = {31346602},
issn = {1095-8290},
abstract = {BACKGROUND AND AIMS: Fully mycoheterotrophic plants derive carbon and other nutrients from root-associated fungi and have lost the ability to photosynthesize. While mycoheterotroph plastomes are often degraded compared to green plants, the effect of this unusual symbiosis on mitochondrial genome evolution is unknown. By providing the first complete organelle genome data from Polygalaceae, one of only three eudicot families that developed mycoheterotrophy, we explore how both organellar genomes evolved after photosynthesis loss.<br><br>METHODS: We sequenced and assembled four complete plastid genomes and a mitochondrial genome from species of Polygalaceae, focusing on non-photosynthetic Epirixanthes. We compared these genomes to those of other mycoheterotroph and parasitic plant lineages, and assessed whether organelle genes in Epirixanthes experienced relaxed or intensified selection compared to autotrophic relatives.<br><br>KEY RESULTS: Plastomes of two species of Epirixanthes have become substantially degraded compared to that of autotrophic Polygala. Although the lack of photosynthesis is presumably homologous in the genus, the surveyed Epirixanthes species have marked differences in terms of plastome size, structural rearrangements, gene content and substitution rates. Remarkably, both apparently replaced a canonical plastid inverted repeat with large directly repeated sequences. The mitogenome of E. elongata incorporated a considerable number of fossilized plastid genes, by intracellular transfer from an ancestor with a less degraded plastome. Both plastid and mitochondrial genes in E. elongata have increased substitution rates, but the plastid genes of E. pallida do not. Despite this, both species have similar selection patterns operating on plastid housekeeping genes.<br><br>CONCLUSIONS: Plastome evolution largely fits with patterns of gene degradation seen in other heterotrophic plants, but includes highly unusual directly duplicated regions. The causes of rate elevation in the sequenced Epirixanthes mitogenome and of rate differences in plastomes of related mycoheterotrophic species are not currently understood.},
}
@article {pmid31345767,
year = {2019},
author = {Rueckert, S and Betts, EL and Tsaousis, AD},
title = {The Symbiotic Spectrum: Where Do the Gregarines Fit?.},
journal = {Trends in parasitology},
volume = {35},
number = {9},
pages = {687-694},
doi = {10.1016/j.pt.2019.06.013},
pmid = {31345767},
issn = {1471-5007},
abstract = {Gregarine apicomplexans are closely related to parasites such as Plasmodium, Toxoplasma, and Cryptosporidium, which are causing severe health and economic burdens. Colonizing only invertebrates and having no obvious medical relevance, they are mostly ignored in 'omics' studies, although gregarines are the most basal apicomplexans and therefore key players in the understanding of the evolution of parasitism in the Apicomplexa from free-living ancestors. They belong to the largest exclusively parasitic phylum, but is this perception actually true? The effects of gregarines on their hosts seem to cover the whole spectrum of symbiosis from mutualistic to parasitic. We suggest future research directions to understand the evolutionary role of gregarines, by elucidating their biology and interaction with their hosts and the hosts' microbiota.},
}
@article {pmid31342139,
year = {2019},
author = {Ogawa, W and Takeda, Y and Endo, N and Yamashita, S and Takayama, T and Fukuda, M and Yamada, A},
title = {Repeated fruiting of Japanese golden chanterelle in pot culture with host seedlings.},
journal = {Mycorrhiza},
volume = {},
number = {},
pages = {},
doi = {10.1007/s00572-019-00908-z},
pmid = {31342139},
issn = {1432-1890},
support = {KAKENHI 15H01751//Japan Society for the Promotion of Science ()/ ; general research grant//Institute for Fermentation, Osaka/ ; },
abstract = {Yellow chanterelles are among the most popular wild edible ectomycorrhizal mushrooms worldwide. The representative European golden chanterelle, Cantharellus cibarius, has only once been reported to fruit under greenhouse conditions, due to the difficulty of establishing pure culture. Recently, we developed a new technique for establishing a pure culture of a Japanese golden chanterelle (Cantharellus anzutake), and conducted in vitro ectomycorrhizal synthesis using established strains and Pinus densiflora. Acclimated pine mycorrhizal seedlings colonized with C. anzutake in a pot system under laboratory conditions produced small but distinct basidiomata with developed basidiospores. C. anzutake mycorrhizae were established on Quercus serrata seedlings by inoculation of mycorrhizal root tips of the fungus synthesized on P. densiflora. A scaled-up C. anzutake-host system in larger pots (4 L soil volume) exhibited repeated fruiting at 20-24 °C under continuous light illumination at 150 μmol m-2 s-1 during a 2-year incubation period. Therefore, a C. anzutake cultivation trial is practical under controlled environmental conditions.},
}
@article {pmid31338082,
year = {2019},
author = {Bernasconi, R and Stat, M and Koenders, A and Paparini, A and Bunce, M and Huggett, MJ},
title = {Establishment of Coral-Bacteria Symbioses Reveal Changes in the Core Bacterial Community With Host Ontogeny.},
journal = {Frontiers in microbiology},
volume = {10},
number = {},
pages = {1529},
doi = {10.3389/fmicb.2019.01529},
pmid = {31338082},
issn = {1664-302X},
abstract = {Bacterial communities are fundamental symbionts of corals. However, the process by which bacterial communities are acquired across the life history of corals, particularly in larval and early juvenile stages, is still poorly characterized. Here, transfer of bacteria of the Scleractinian coral Acropora digitifera from adults to spawned egg-sperm bundles was analyzed, as well as acquisition across early developmental stages (larvae and newly settled spat), and 6-month-old juveniles. Larvae were reared under manipulated environmental conditions to determine the source (maternal, seawater, or sediment) of bacteria likely to establish symbiotic relationships with the host using amplicon sequencing of the 16S rRNA gene. Maternal colonies directly transferred bacteria from the families Rhodobacteraceae, Cryomorphaceae, and Endozoicimonaceae to egg-sperm bundles. Furthermore, significant differences in the microbial community structure were identified across generations, yet the structure of the coral bacterial community across early life history stages was not impacted by different environmental rearing conditions. These data indicate that the uptake and structure of bacterial communities is developmentally, rather than environmentally, regulated. Both maternal coral colonies and ubiquitous bacteria found across environmental substrates represent a potential source of symbionts important in establishing the coral microbiome. Uniquely, we report the presence of variation with ontogeny of both the core and resident bacterial communities, supporting the hypothesis that microbial communities are likely to play specific roles within the distinct life history stages of the coral host.},
}
@article {pmid31337682,
year = {2019},
author = {Feng, H and Edwards, N and Anderson, CMH and Althaus, M and Duncan, RP and Hsu, YC and Luetje, CW and Price, DRG and Wilson, ACC and Thwaites, DT},
title = {Trading amino acids at the aphid-Buchnera symbiotic interface.},
journal = {Proceedings of the National Academy of Sciences of the United States of America},
volume = {116},
number = {32},
pages = {16003-16011},
doi = {10.1073/pnas.1906223116},
pmid = {31337682},
issn = {1091-6490},
abstract = {Plant sap-feeding insects are widespread, having evolved to occupy diverse environmental niches despite exclusive feeding on an impoverished diet lacking in essential amino acids and vitamins. Success depends exquisitely on their symbiotic relationships with microbial symbionts housed within specialized eukaryotic bacteriocyte cells. Each bacteriocyte is packed with symbionts that are individually surrounded by a host-derived symbiosomal membrane representing the absolute host-symbiont interface. The symbiosomal membrane must be a dynamic and selectively permeable structure to enable bidirectional and differential movement of essential nutrients, metabolites, and biosynthetic intermediates, vital for growth and survival of host and symbiont. However, despite this crucial role, the molecular basis of membrane transport across the symbiosomal membrane remains unresolved in all bacteriocyte-containing insects. A transport protein was immunolocalized to the symbiosomal membrane separating the pea aphid Acyrthosiphon pisum from its intracellular symbiont Buchnera aphidicola The transporter, A. pisum nonessential amino acid transporter 1, or ApNEAAT1 (gene: ACYPI008971), was characterized functionally following heterologous expression in Xenopus oocytes, and mediates both inward and outward transport of small dipolar amino acids (serine, proline, cysteine, alanine, glycine). Electroneutral ApNEAAT1 transport is driven by amino acid concentration gradients and is not coupled to transmembrane ion gradients. Previous metabolite profiling of hemolymph and bacteriocyte, alongside metabolic pathway analysis in host and symbiont, enable prediction of a physiological role for ApNEAAT1 in bidirectional host-symbiont amino acid transfer, supplying both host and symbiont with indispensable nutrients and biosynthetic precursors to facilitate metabolic complementarity.},
}
@article {pmid31337355,
year = {2019},
author = {Armaleo, D and Müller, O and Lutzoni, F and Andrésson, ÓS and Blanc, G and Bode, HB and Collart, FR and Dal Grande, F and Dietrich, F and Grigoriev, IV and Joneson, S and Kuo, A and Larsen, PE and Logsdon, JM and Lopez, D and Martin, F and May, SP and McDonald, TR and Merchant, SS and Miao, V and Morin, E and Oono, R and Pellegrini, M and Rubinstein, N and Sanchez-Puerta, MV and Savelkoul, E and Schmitt, I and Slot, JC and Soanes, D and Szövényi, P and Talbot, NJ and Veneault-Fourrey, C and Xavier, BB},
title = {The lichen symbiosis re-viewed through the genomes of Cladonia grayi and its algal partner Asterochloris glomerata.},
journal = {BMC genomics},
volume = {20},
number = {1},
pages = {605},
doi = {10.1186/s12864-019-5629-x},
pmid = {31337355},
issn = {1471-2164},
support = {IGSP 2008001//Duke Institute for Genomic Sciences and Policy/ ; FWP 61327//U.S. Department of Energy/ ; DE-AC02-05CH11231//U.S. Department of Energy/ ; DE-FC02-02ER63421//U.S. Department of Energy/ ; 112442//U.S. Department of Energy/ ; 1011101//National Science Foundation/ ; },
abstract = {BACKGROUND: Lichens, encompassing 20,000 known species, are symbioses between specialized fungi (mycobionts), mostly ascomycetes, and unicellular green algae or cyanobacteria (photobionts). Here we describe the first parallel genomic analysis of the mycobiont Cladonia grayi and of its green algal photobiont Asterochloris glomerata. We focus on genes/predicted proteins of potential symbiotic significance, sought by surveying proteins differentially activated during early stages of mycobiont and photobiont interaction in coculture, expanded or contracted protein families, and proteins with differential rates of evolution.<br><br>RESULTS: A) In coculture, the fungus upregulated small secreted proteins, membrane transport proteins, signal transduction components, extracellular hydrolases and, notably, a ribitol transporter and an ammonium transporter, and the alga activated DNA metabolism, signal transduction, and expression of flagellar components. B) Expanded fungal protein families include heterokaryon incompatibility proteins, polyketide synthases, and a unique set of G-protein α subunit paralogs. Expanded algal protein families include carbohydrate active enzymes and a specific subclass of cytoplasmic carbonic anhydrases. The alga also appears to have acquired by horizontal gene transfer from prokaryotes novel archaeal ATPases and Desiccation-Related Proteins. Expanded in both symbionts are signal transduction components, ankyrin domain proteins and transcription factors involved in chromatin remodeling and stress responses. The fungal transportome is contracted, as are algal nitrate assimilation genes. C) In the mycobiont, slow-evolving proteins were enriched for components involved in protein translation, translocation and sorting.<br><br>CONCLUSIONS: The surveyed genes affect stress resistance, signaling, genome reprogramming, nutritional and structural interactions. The alga carries many genes likely transferred horizontally through viruses, yet we found no evidence of inter-symbiont gene transfer. The presence in the photobiont of meiosis-specific genes supports the notion that sexual reproduction occurs in Asterochloris while they are free-living, a phenomenon with implications for the adaptability of lichens and the persistent autonomy of the symbionts. The diversity of the genes affecting the symbiosis suggests that lichens evolved by accretion of many scattered regulatory and structural changes rather than through introduction of a few key innovations. This predicts that paths to lichenization were variable in different phyla, which is consistent with the emerging consensus that ascolichens could have had a few independent origins.},
}
@article {pmid31333627,
year = {2019},
author = {Ruiz, B and Le Scornet, A and Sauviac, L and Rémy, A and Bruand, C and Meilhoc, E},
title = {The Nitrate Assimilatory Pathway in Sinorhizobium meliloti: Contribution to NO Production.},
journal = {Frontiers in microbiology},
volume = {10},
number = {},
pages = {1526},
doi = {10.3389/fmicb.2019.01526},
pmid = {31333627},
issn = {1664-302X},
abstract = {The interaction between rhizobia and their legume host plants culminates in the formation of specialized root organs called nodules in which differentiated endosymbiotic bacteria (bacteroids) fix atmospheric nitrogen to the benefit of the plant. Interestingly, nitric oxide (NO) has been detected at various steps of the rhizobium-legume symbiosis where it has been shown to play multifaceted roles. It is recognized that both bacterial and plant partners of the Sinorhizobium meliloti-Medicago truncatula symbiosis are involved in NO synthesis in nodules. S. meliloti can also produce NO from nitrate when living as free cells in the soil. S. meliloti does not possess any NO synthase gene in its genome. Instead, the denitrification pathway is often described as the main driver of NO production with nitrate as substrate. This pathway includes the periplasmic nitrate reductase (Nap) which reduces nitrate into nitrite, and the nitrite reductase (Nir) which reduces nitrite into NO. However, additional genes encoding putative nitrate and nitrite reductases (called narB and nirB, respectively) have been identified in the S. meliloti genome. Here we examined the conditions where these genes are expressed, investigated their involvement in nitrate assimilation and NO synthesis in culture and their potential role in planta. We found that narB and nirB are expressed under aerobic conditions in absence of ammonium in the medium and most likely belong to the nitrate assimilatory pathway. Even though these genes are clearly expressed in the fixation zone of legume root nodule, they do not play a crucial role in symbiosis. Our results support the hypothesis that in S. meliloti, denitrification remains the main enzymatic way to produce NO while the assimilatory pathway involving NarB and NirB participates indirectly to NO synthesis by cooperating with the denitrification pathway.},
}
@article {pmid31333602,
year = {2019},
author = {Nouioui, I and Cortés-Albayay, C and Carro, L and Castro, JF and Gtari, M and Ghodhbane-Gtari, F and Klenk, HP and Tisa, LS and Sangal, V and Goodfellow, M},
title = {Genomic Insights Into Plant-Growth-Promoting Potentialities of the Genus Frankia.},
journal = {Frontiers in microbiology},
volume = {10},
number = {},
pages = {1457},
doi = {10.3389/fmicb.2019.01457},
pmid = {31333602},
issn = {1664-302X},
abstract = {This study was designed to determine the plant growth promoting (PGP) potential of members of the genus Frankia. To this end, the genomes of 21 representative strains were examined for genes associated directly or indirectly with plant growth. All of the Frankia genomes contained genes that encoded for products associated with the biosynthesis of auxins [indole-3-glycerol phosphate synthases, anthranilate phosphoribosyltransferases (trpD), anthranilate synthases, and aminases (trpA and B)], cytokinins (11 well-conserved genes within the predicted biosynthetic gene cluster), siderophores, and nitrogenases (nif operon except for atypical Frankia) as well as genes that modulate the effects of biotic and abiotic environmental stress (e.g., alkyl hydroperoxide reductases, aquaporin Z, heat shock proteins). In contrast, other genes were associated with strains assigned to one or more of four host-specific clusters. The genes encoding for phosphate solubilization (e.g., low-affinity inorganic phosphate transporters) and lytic enzymes (e.g., cellulases) were found in Frankia cluster 1 genomes, while other genes were found only in cluster 3 genomes (e.g., alkaline phosphatases, extracellular endoglucanases, pectate lyases) or cluster 4 and subcluster 1c genomes (e.g., NAD(P) transhydrogenase genes). Genes encoding for chitinases were found only in the genomes of the type strains of Frankia casuarinae, F. inefficax, F. irregularis, and F. saprophytica. In short, these in silico genome analyses provide an insight into the PGP abilities of Frankia strains of known taxonomic provenance. This is the first study designed to establish the underlying genetic basis of cytokinin production in Frankia strains. Also, the discovery of additional genes in the biosynthetic gene cluster involved in cytokinin production opens up the prospect that Frankia may have novel molecular mechanisms for cytokinin biosynthesis.},
}
@article {pmid31332951,
year = {2019},
author = {Gilbert, SF},
title = {Developmental symbiosis facilitates the multiple origins of herbivory.},
journal = {Evolution &amp; development},
volume = {},
number = {},
pages = {e12291},
doi = {10.1111/ede.12291},
pmid = {31332951},
issn = {1525-142X},
support = {IOS-145177//National Science Foundation/ ; },
abstract = {Developmental bias toward particular evolutionary trajectories can be facilitated through symbiosis. Organisms are holobionts, consisting of zygote-derived cells and a consortia of microbes, and the development, physiology, and immunity of animals are properties of complex interactions between the zygote-derived cells and microbial symbionts. Such symbionts can be agents of developmental plasticity, allowing an organism to develop in particular directions. This plasticity can lead to genetic assimilation either through the incorporation of microbial genes into host genomes or through the direct maternal transmission of the microbes. Such plasticity can lead to niche construction, enabling the microbes to remodel host anatomy and/or physiology. In this article, I will focus on the ability of symbionts to bias development toward the evolution of herbivory. I will posit that the behavioral and morphological manifestations of herbivorous phenotypes must be preceded by the successful establishment of a community of symbiotic microbes that can digest cell walls and detoxify plant poisons. The ability of holobionts to digest plant materials can range from being a plastic trait, dependent on the transient incorporation of environmental microbes, to becoming a heritable trait of the holobiont organism, transmitted through the maternal propagation of symbionts or their genes.},
}
@article {pmid31332487,
year = {2019},
author = {Singh, RP},
title = {Glycan utilisation system in Bacteroides and Bifidobacteria and their roles in gut stability and health.},
journal = {Applied microbiology and biotechnology},
volume = {103},
number = {18},
pages = {7287-7315},
doi = {10.1007/s00253-019-10012-z},
pmid = {31332487},
issn = {1432-0614},
abstract = {Gut residential hundred trillion microbial cells are indispensable for maintaining gut homeostasis and impact on host physiology, development and immune systems. Many of them have displayed excellence in utilising dietary- and host-derived complex glycans and are producing useful postbiotics including short-chain fatty acids to primarily fuel different organs of the host. Therefore, employing individual microbiota is nowadays becoming a propitious target in biomedical for improving gut dysbiosis conditions of the host. Among other gut microbial communities, Bacteroides and Bifidobacteria are coevolved to utilise diverse ranges of diet- and host-derived glycans through harmonising distinct glycan utilisation systems. These gut symbionts frequently share digested oligosaccharides, carbohydrate-active enzymes and fermentable intermediate molecules for sustaining gut microbial symbiosis and improving fitness of own or other communities. Genomics approaches have provided unprecedented insights into these functions, but their precise mechanisms of action have poorly known. Sympathetic glycan-utilising strategy of each gut commensal will provide overview of mechanistic dynamic nature of the gut environment and will then assist in applying aptly personalised nutritional therapy. Thus, the review critically summarises cutting edge understanding of major plant- and host-derived glycan-utilising systems of Bacteroides and Bifidobacteria. Their evolutionary adaptation to gut environment and roles of postbiotics in human health are also highlighted.},
}
@article {pmid31331977,
year = {2019},
author = {Guckes, KR and Cecere, AG and Wasilko, NP and Williams, AL and Bultman, KM and Mandel, MJ and Miyashiro, T},
title = {Incompatibility of Vibrio fischeri strains during symbiosis establishment depends on two functionally redundant hcp genes.},
journal = {Journal of bacteriology},
volume = {},
number = {},
pages = {},
doi = {10.1128/JB.00221-19},
pmid = {31331977},
issn = {1098-5530},
support = {R01 GM129133/GM/NIGMS NIH HHS/United States ; },
abstract = {Bacteria that have the capacity to fill the same niche will compete with one another for space and resources available within an ecosystem. Such competition is heightened among different strains of the same bacterial species. Nevertheless, different strains often inhabit the same host. The molecular mechanisms that impact competition between different strains within the same host are poorly understood. To address this knowledge gap, the type VI secretion system (T6SS), which is a mechanism for bacteria to kill neighboring cells, was examined in the marine bacterium Vibrio fischeri Different strains of V. fischeri naturally colonize the light organ of the bobtail squid Euprymna scolopes The genome of FQ-A001, which is a T6SS-positive strain, features two hcp genes that are predicted to encode identical subunits of the T6SS. Co-incubation assays showed that either hcp gene is sufficient for FQ-A001 to kill another strain via T6SS in vitro Additionally, induction of hcp expression is sufficient to induce killing activity in an Hcp- mutant of FQ-A001. Squid colonization assays involving inoculums of FQ-A001-derived strains mixed with ES114 revealed that both hcp genes must be deleted for FQ-A001 and ES114 to occupy the same space within the light organ. These experimental results provide insight into the genetic factors necessary for the T6SS of V. fischeri to function in vivo, thereby increasing understanding of the molecular mechanisms that impact strain diversity within a host.IMPORTANCE Different bacterial strains compete to occupy the same niche. The outcome from such competition can be affected by the type VI secretion system (T6SS), which is an intercellular killing mechanism of bacteria. Here, an animal-bacterial symbiosis is used as a platform to study the genetic factors that promote T6SS-mediated killing of one strain by another strain. Identification of the molecular determinants of T6SS function in vivo contributes to the understanding of how different strains interact within a host.},
}
@article {pmid31331976,
year = {2019},
author = {Lynch, JB and Schwartzman, JA and Bennett, BD and McAnulty, SJ and Knop, M and Nyholm, SV and Ruby, EG},
title = {Ambient pH alters protein content of outer membrane vesicles, driving host development in a beneficial symbiosis.},
journal = {Journal of bacteriology},
volume = {},
number = {},
pages = {},
doi = {10.1128/JB.00319-19},
pmid = {31331976},
issn = {1098-5530},
abstract = {Outer membrane vesicles (OMVs) are continuously produced by Gram-negative bacteria, and are increasingly recognized as ubiquitous mediators of bacterial physiology. In particular, OMVs are powerful effectors in inter-organismal interactions, driven largely by their molecular contents. These impacts have been studied extensively in bacterial pathogenesis, but have not been well documented within the context of mutualism. Here, we examined the proteomic composition of OMVs from the marine bacterium Vibrio fischeri, which forms a specific mutualism with the Hawaiian bobtail squid, Euprymna scolopes We found that V. fischeri upregulates transcription of its major outer membrane protein, OmpU, during growth at an acidic pH, which V. fischeri experiences when it transitions from its environmental reservoir to host tissues. We used comparative genomics and DNA pull-down analyses to search for regulators of ompU, and found that differential expression of ompU is governed by the OmpR, H-NS, and ToxR proteins. This transcriptional control combines with nutritional conditions to govern OmpU levels in OMVs. Under a host-encountered acidic pH, V. fischeri OMVs become more potent stimulators of symbiotic host development in an OmpU-dependent manner. Finally, we found that symbiotic development could be stimulated by OMVs containing a homolog of OmpU from the pathogenic species Vibrio cholerae, connecting the role of a well-described virulence factor with a mutualistic element. This work explores the symbiotic effects of OMV variation, identifies shared regulatory machinery between pathogenic and mutualistic bacteria, and provides evidence of the role that OMVs play in animal-bacteria mutualism.Importance Beneficial bacteria communicate with their hosts through a variety of means. These communications are often carried out by a combination of molecules that stimulate responses from the host and are necessary for development of the relationship between these organisms. Naturally produced bacterial outer membrane vesicles (OMVs) contain many of those molecules and can stimulate a wide range of responses from recipient organisms. Here, we describe how a marine bacterium, Vibrio fischeri, changes the makeup of its OMVs under conditions that it experiences as it goes from its free-living lifestyle to associating with its natural host, the Hawaiian bobtail squid. This work improves our understanding of how bacteria change their signaling profile as they begin to associate with their beneficial partner animals.},
}
@article {pmid31330021,
year = {2019},
author = {Ji, J and Luo, CL and Zou, X and Lv, XH and Xu, YB and Shu, DM and Qu, H},
title = {Association of host genetics with intestinal microbial relevant to body weight in a chicken F2 resource population.},
journal = {Poultry science},
volume = {98},
number = {9},
pages = {4084-4093},
doi = {10.3382/ps/pez199},
pmid = {31330021},
issn = {1525-3171},
abstract = {Host-microbiota interactions describe a co-evolution and mutualistic symbiosis. Gut microbial communities are important for diverse host functions. However, in birds, the relationship between the composition of the intestinal microbiota and the genetic variation of the host is not clearly understood. To dissect these interactions, a Chinese yellow broiler line (genetically selected for a high growth rate) and Huiyang Beard chickens (low growth rate) were crossed, generating an F2 population. The population structures of the gut microbes in the phenotypically high and low 91-d body weight individuals of both sexes in the F2 population were studied. Interestingly, a non-metric multidimensional scaling analysis revealed that the microbiota of the high-weight and low-weight females was clearly separated into 2 clusters. A β-diversity analysis showed that the locus rs16775833 within the doublesex and mab-3-related transcription factor (DMRT) gene cluster accounted for approximately 21% of the variation in the population structure of the gut microbiota. Furthermore, the 2 genetic loci rs15142709 and rs15142674 were significantly associated with specific species of Methanobacterium. These loci are located in the pleiomorphic adenoma gene 1 (PLAG1) and lck/yes-related novel tyrosine kinase (LYN) genes, which are involved in cell differentiation and growth. This finding suggests evidence for the influence of the host genetics on the composition of the gut microbiota in birds and the importance and utility of the host-microbe status to better understand its effect on the potential growth of birds.},
}
@article {pmid31329832,
year = {2019},
author = {Cardós, JLH and Prieto, M and Jylhä, M and Aragón, G and Molina, MC and Martínez, I and Rikkinen, J},
title = {A case study on the re-establishment of the cyanolichen symbiosis: where do the compatible photobionts come from?.},
journal = {Annals of botany},
volume = {},
number = {},
pages = {},
doi = {10.1093/aob/mcz052},
pmid = {31329832},
issn = {1095-8290},
abstract = {BACKGROUND AND AIMS: In order to re-establish lichen symbiosis, fungal spores must first germinate and then associate with a compatible photobiont. To detect possible establishment limitations in a sexually reproducing cyanolichen species, we studied ascospore germination, photobiont growth and photobiont association patterns in Pectenia plumbea.<br><br>METHODS: Germination tests were made with ascospores from 500 apothecia under different treatments, and photobiont growth was analysed in 192 isolates obtained from 24 thalli. We determined the genotype identity [tRNALeu (UAA) intron] of the Nostoc cyanobionts from 30 P. plumbea thalli from one population. We also sequenced cyanobionts of 41 specimens of other cyanolichen species and 58 Nostoc free-living colonies cultured from the bark substrate.<br><br>KEY RESULTS: Not a single fungal ascospore germinated and none of the photobiont isolates produced motile hormogonia. Genetic analyses revealed that P. plumbea shares Nostoc genotypes with two other cyanolichen species of the same habitat, but these photobionts were hardly present in the bark substrate.<br><br>CONCLUSIONS: Due to the inability of both symbionts to thrive independently, the establishment of P. plumbea seems to depend on Dendriscocaulon umhausense, the only cyanolichen species in the same habitat that reproduces asexually and acts as a source of appropriate cyanobionts. This provides support to the hypothesis about facilitation among lichens.},
}
@article {pmid31328784,
year = {2019},
author = {Muñoz-Gómez, SA and Durnin, K and Eme, L and Paight, C and Lane, CE and Saffo, MB and Slamovits, CH},
title = {Nephromyces represents a diverse and novel lineage of the Apicomplexa that has retained apicoplasts.},
journal = {Genome biology and evolution},
volume = {},
number = {},
pages = {},
doi = {10.1093/gbe/evz155},
pmid = {31328784},
issn = {1759-6653},
abstract = {A most interesting exception within the parasitic Apicomplexa is Nephromyces, an extracellular, probably mutualistic, endosymbiont found living inside molgulid ascidian tunicates (i.e., sea squirts). Even though Nephromyces is now known to be an apicomplexan, many other questions about its nature remain unanswered. To gain further insights into the biology and evolutionary history of this unusual apicomplexan, we aimed to (1) find the precise phylogenetic position of Nephromyces within the Apicomplexa, (2) search for the apicoplast genome of Nephromyces, and (3) infer the major metabolic pathways in the apicoplast of Nephromyces. To do this, we sequenced a metagenome and a metatranscriptome from the molgulid renal sac, the specialized habitat where Nephromyces thrives. Our phylogenetic analyses of conserved nucleus-encoded genes robustly suggest that Nephromyces is a novel lineage sister to the Hematozoa, which comprises both the Haemosporidia (e.g., Plasmodium) and the Piroplasmida (e.g., Babesia and Theileria). Furthermore, a survey of the renal sac metagenome revealed 13 small contigs that closely resemble the genomes of the non-photosynthetic reduced plastids, or apicoplasts, of other apicomplexans. We show that these apicoplast genomes correspond to a diverse set of most closely related but genetically divergent Nephromyces lineages that co-inhabit a single tunicate host. In addition, the apicoplast of Nephromyces appears to have retained all biosynthetic pathways inferred to have been ancestral to parasitic apicomplexans. Our results shed light on the evolutionary history of the only probably mutualistic apicomplexan known, Nephromyces, and provide context for a better understanding of its life style and intricate symbiosis.},
}
@article {pmid31328352,
year = {2019},
author = {Khemaissia, H and Jelassi, R and Ghemari, C and Raimond, M and Souty-Grosset, C and Nasri-Ammar, K},
title = {Effects of trace metal elements on ultrastructural features of hepatopancreas of Armadillidium granulatum Brandt, 1833 (Crustacea, Isopoda).},
journal = {Microscopy research and technique},
volume = {},
number = {},
pages = {},
doi = {10.1002/jemt.23349},
pmid = {31328352},
issn = {1097-0029},
support = {LR18ES06//Laboratory of Diversity, Management and Conservation of Biological Systems/ ; },
abstract = {This study was conducted to compare metals bioaccumulation in the terrestrial isopod Armadillidium granulatum collected from Ghar El Melh lagoon. We focused on recognizing the effects of trace elements on hepatopancreas functional role. To this end, isopod specimens were exposed for 3 weeks to sediments contaminated with cadmium, copper, zinc, mercury, and nickel. Three concentrations were used in duplicate for each experimental condition. At the end of the experiment, metal body burdens were determined using flame atomic absorption spectrometry. Results of the bioaccumulation factor (BAF) showed that the species A. granulatum was classified as a Cu macroconcentrator (BAF > 2) and a Zn deconcentrator (BAF < 2). Dose dependent morphological and histological changes were observed in the hepatopancreas cells using transmission electron microscopy. The predominant features were: microvillus border disruption, condensation of the cytoplasm with increasing endoplasmic reticulum, mitochondria, lysosomes and granules that accumulated metals in B and S cells. The number of lipid droplets decreased especially after Cd, Zn, Hg, and Ni treatments. This study demonstrated that the terrestrial isopod A. gramulatum could be a good indicator of soil metal contamination.},
}
@article {pmid31327928,
year = {2019},
author = {Xie, L and Chen, YL and Long, YY and Zhang, Y and Liao, ST and Liu, B and Qin, LP and Nong, Q and Zhang, WL},
title = {Three new species of Conlarium from sugarcane rhizosphere in southern China.},
journal = {MycoKeys},
volume = {56},
number = {},
pages = {1-11},
doi = {10.3897/mycokeys.56.35857},
pmid = {31327928},
issn = {1314-4049},
abstract = {Three new species isolated from sugarcane rhizosphere in China, namely Conlariumbaiseensesp. nov., C.nanningensesp. nov., and C.saccharisp. nov., are described and illustrated. Molecular evidence (phylogenetic analysis of combined LSU, SSU, ITS and RPB2 sequence data) and phenotypical characters support their independent status from related and similar species. The new species, as dark spetate endophytes, inhabit sugarcane rhizosphere and can form a symbiosis with sugarcane.},
}
@article {pmid31327121,
year = {2019},
author = {Fileccia, V and Ingraffia, R and Amato, G and Giambalvo, D and Martinelli, F},
title = {Identification of microRNAS differentially regulated by water deficit in relation to mycorrhizal treatment in wheat.},
journal = {Molecular biology reports},
volume = {},
number = {},
pages = {},
doi = {10.1007/s11033-019-04974-6},
pmid = {31327121},
issn = {1573-4978},
abstract = {Arbuscular mycorrhizal fungi (AMF) are soil microrganisms that establish symbiosis with plants positively influencing their resistance to abiotic stresses. The aim of this work was to identify wheat miRNAs differentially regulated by water deficit conditions in presence or absence of AMF treatment. Small RNA libraries were constructed for both leaf and root tissues considering four conditions: control (irrigated) or water deficit in presence/absence of mycorrhizal (AMF) treatment. A total of 12 miRNAs were significantly regulated by water deficit in leaves: five in absence and seven in presence of AMF treatment. In roots, three miRNAs were water deficit-modulated in absence of mycorrhizal treatment while six were regulated in presence of it. The most represented miRNA family was miR167 that was regulated by water deficit in both leaf and root tissues. Interestingly, miR827-5p was differentially regulated in leaves in the absence of mycorrhizal treatment while it was water deficit-modulated in roots irrespective of AMF treatment. In roots, water deficit repressed miR827-5p, miR394, miR6187, miR167e-3p, and miR9666b-3p affecting transcription, RNA synthesis, protein synthesis, and protein modifications. In leaves, mycorrhizae modulated miR5384-3p and miR156e-3p affecting trafficking and cell redox homeostasis. DNA replication and transcription regulation should be targeted by the repression of miR1432-5p and miR166h-3p. This work provided interesting insights into the post-transcriptional mechanisms of wheat responses to water deficit in relation to mycorrhizal symbiosis.},
}
@article {pmid31325057,
year = {2019},
author = {Zhang, S and Kondorosi, É and Kereszt, A},
title = {An anthocyanin marker for direct visualization of plant transformation and its use to study nitrogen-fixing nodule development.},
journal = {Journal of plant research},
volume = {132},
number = {5},
pages = {695-703},
doi = {10.1007/s10265-019-01126-6},
pmid = {31325057},
issn = {1618-0860},
support = {OTKA 120120/119652//Hungarian National Office for Research, Development and Innovation/ ; GINOP 2.3.2-15-2016-00014//Hungarian National Office for Research, Development and Innovation/ ; GINOP 2.3.2-15-2016-00015//Hungarian National Office for Research, Development and Innovation/ ; },
abstract = {The development and functioning of the nitrogen fixing symbiosis between legume plants and soil bacteria collectively called rhizobia requires continuous chemical dialogue between the partners using different molecules such as flavonoids, lipo-chitooligosaccharides, polysaccharides and peptides. Agrobacterium rhizogenes mediated hairy root transformation of legumes is widely used to study the function of plant genes involved in the process. The identification of transgenic plant tissues is based on antibiotics/herbicide selection and/or the detection of different reporter genes that usually require special equipment such as fluorescent microscopes or destructive techniques and chemicals to visualize enzymatic activity. Here, we developed and efficiently used in hairy root experiments binary vectors containing the MtLAP1 gene driven by constitutive and tissue-specific promoters that facilitate the production of purple colored anthocyanins in transgenic tissues and thus allowing the identification of transformed roots by naked eye. Anthocyanin producing roots were able to establish effective symbiosis with rhizobia. Moreover, it was shown that species-specific allelic variations and a mutation preventing posttranslational acetyl modification of an essential nodule-specific cysteine-rich peptide, NCR169, do not affect the symbiotic interaction of Medicago truncatula cv. Jemalong with Sinorhizobium medicae strain WSM419. Based on the experiments, it could be concluded that it is preferable to use the vectors with tissue-specific promoters that restrict anthocyanin production to the root vasculature for studying biotic interactions of the roots such as symbiotic nitrogen fixation or mycorrhizal symbiosis.},
}
@article {pmid31323808,
year = {2019},
author = {Faluaburu, MS and Nakai, R and Imura, S and Naganuma, T},
title = {Phylotypic Characterization of Mycobionts and Photobionts of Rock Tripe Lichen in East Antarctica.},
journal = {Microorganisms},
volume = {7},
number = {7},
pages = {},
doi = {10.3390/microorganisms7070203},
pmid = {31323808},
issn = {2076-2607},
support = {JP16H05765//Japan Society for the Promotion of Science/ ; },
abstract = {Saxicolous rock ripe lichens that grow on rocks in the East Antarctic fellfields were sampled for phylotypic characterization of its constituent mycobionts (fungi) and photobionts (algae and cyanobacteria). The rock tripe lichen-forming fungal and algal phylotypes were classified under the common lichen-forming genera of ascomycetes, namely, Umbilicaria, and green algae, namely, Trebouxia and Coccomyxa. However, phylotypes of the green algal chloroplasts and the lichen-associated cyanobacteria showed unexpectedly high diversity. The detected chloroplast phylotypes were not fully affiliated with the green algal genera Trebouxia or Coccomyxa. The predominant chloroplast phylotype demonstrated maximum resemblance to Neglectella solitaria, which is neither a known Antarctic species nor a typical lichen photobiont. Another dominant chloroplast phylotype belonged to the atypical Antarctic green algae family. Cyanobacterial phylotypes were dominated by those affiliated with the Microcoleus species rather than the well-known lichen-associates, Nostoc species. The occurrences of these Microcoleus-affiliated cyanobacterial phylotypes were specifically abundant within the Yukidori Valley site, one of the Antarctic Specially Protected Areas (ASPA). The ASPA site, along with another 50 km-distant site, yielded most of the cryptic diversity in the phylotypes of chloroplasts and cyanobacteria, which may contribute to the phenotypic variability within the rock tripe lichen photobionts.},
}
@article {pmid31323069,
year = {2019},
author = {Morishima, SY and Yamashita, H and O-Hara, S and Nakamura, Y and Quek, VZ and Yamauchi, M and Koike, K},
title = {Study on expelled but viable zooxanthellae from giant clams, with an emphasis on their potential as subsequent symbiont sources.},
journal = {PloS one},
volume = {14},
number = {7},
pages = {e0220141},
doi = {10.1371/journal.pone.0220141},
pmid = {31323069},
issn = {1932-6203},
abstract = {Unlike most bivalve shellfishes, giant clams (tridacnines) harbor symbiotic microalgae (zooxanthellae) in their fleshy bodies. Zooxanthellae are not maternally inherited by tridacnine offspring, hence, the larvae must acquire zooxanthellae from external sources, although such algal populations or sources in the environment are currently unknown. It is well known that giant clams expel fecal pellets that contain viable zooxanthellae cells, but whether these cells are infectious or just an expelled overpopulation from the giant clams has not been investigated. In this study, we observed the ultrastructural and photosynthetic competencies of zooxanthellae in the fecal pellets of Tridacna crocea and further tested the ability of these cells to infect T. squamosa juveniles. The ultrastructure of the zooxanthellae cells showed that the cells were intact and had not undergone digestion. Additionally, these zooxanthellae cells showed a maximum quantum yield of photosystem II (Fv/Fm) as high as those retained in the mantle of the giant clam. Under the assumption that feces might provide symbionts to the larvae of other giant clams, fecal pellets from Tridacna squamosa and T. crocea were given to artificially hatched 1-day-old T. squamosa larvae. On the 9th day, 15-34% of the larvae provided with the fecal pellets took up zooxanthellae in their stomach, and on the 14th day, zooxanthellae cells reached the larval margin, indicating the establishment of symbiosis. The rate reaching this stage was highest, ca. 5.3%, in the larvae given whole (nonhomogenized) pellets from T. crocea. The composition of zooxanthellae genera contained in the larvae were similar to those in the fecal pellets, although the abundance ratios were significantly different. This study is the first to demonstrate the potential of giant clam fecal pellets as symbiont vectors to giant clam larvae. These results also demonstrate the possibility that fecal pellets are a source of zooxanthellae in coral reefs.},
}
@article {pmid31319203,
year = {2019},
author = {Ingavle, G and Shabrani, N and Vaidya, A and Kale, V},
title = {Mimicking megakaryopoiesis in vitro using biomaterials: Recent advances and future opportunities.},
journal = {Acta biomaterialia},
volume = {96},
number = {},
pages = {99-110},
doi = {10.1016/j.actbio.2019.07.025},
pmid = {31319203},
issn = {1878-7568},
abstract = {Presently donor-derived platelets used in the clinic are associated with concerns about adequate availability, expense, risk of bacterial contamination and complications due to immunological reaction. To prevail over our dependence on transfusion of donor-derived platelets, efforts are being made to generate them in vitro. Development of biomaterials that support or mimic bone marrow niche micro-environmental cues could improve the in vitro production of platelets from megakaryocytes (MKs) derived from various stem cell sources. In spite of significant advances in the production of MKs from various stem cell sources using 2D as well as 3D culture approaches in vitro and the development of biomaterials-based platelet systems, yield and quality of these platelets remains unsuitable for clinical use. Thus, in vitro production of clinically useful platelets on a large scale remains an unmet target to date. This review summarizes the most frequently used 2D and 3D approaches to generate MKs and platelets in vitro, emphasizing the importance of mimicking in vivo micro-environment. Further, this review proposes the use of interpenetrating network (IPN) biomaterial-based approach as a promising strategy for improving the generation of MK and platelets in sufficient numbers in vitro. STATEMENT OF SIGNIFICANCE: Thrombocytopenia is one of the major global health and socio-economic problems. Transfusion with donor-derived platelets (PLTs) is the only effective treatment for this condition. However, this approach is limited by factors like short shelf-life of PLTs, PLT activation, alloimmunization, risk of bacterial contamination, infection etc. In vitro generated MKs and PLTs derived from non-donor-dependent sources may help to overcome the platelet transfusion concerns. Here we have reviewed various 2D and 3D strategies used for in vitro generation of MKs and PLTs, with special emphasis on various biomaterial platforms and different physico/chemical cues being used for the purpose. We have also proposed a biomaterial-based approach of using interpenetrating network (IPN) for generating clinically relevant numbers of MKs and PLTs.},
}
@article {pmid31317283,
year = {2019},
author = {Ali, HRK and Hemeda, NF and Abdelaliem, YF},
title = {Symbiotic cellulolytic bacteria from the gut of the subterranean termite Psammotermes hypostoma Desneux and their role in cellulose digestion.},
journal = {AMB Express},
volume = {9},
number = {1},
pages = {111},
doi = {10.1186/s13568-019-0830-5},
pmid = {31317283},
issn = {2191-0855},
abstract = {The subterranean termite Psammotermes hypostoma Desneux is considered as an important pest that could cause severe damage to buildings, furniture, silos of grain and crops or any material containing cellulose. This species of termites is widespread in Egypt and Africa. The lower termite's ability to digest cellulose depends on the association of symbiotic organisms gut that digest cellulose (flagellates and bacteria). In this study, 33 different bacterial isolates were obtained from the gut of the termite P. hypostoma which were collected using cellulose traps. Strains were grown on carboxymethylcellulose (CMC) as a sole source of carbon. Cellulolytic strains were isolated in two different cellulose medium (mineral salt medium containing carboxymethylcellulose as the sole carbon source and agar cellulose medium). Five isolates showed significant cellulolytic activity identified by a Congo red assay which gives clear zone. Based on biochemical tests and sequencing of 16s rRNA genes these isolates were identified as Paenibacillus lactis, Lysinibacillus macrolides, Stenotrophomonas maltophilia, Lysinibacillus fusiformis and Bacillus cereus, that deposited in GenBank with accession numbers MG991563, MG991564, MG991565, MG991566 and MG991567, respectively.},
}
@article {pmid31314793,
year = {2019},
author = {Hoe, C and Adhikari, B and Glandon, D and Das, A and Kaur, N and Gupta, S},
title = {Using social network analysis to plan, promote and monitor intersectoral collaboration for health in rural India.},
journal = {PloS one},
volume = {14},
number = {7},
pages = {e0219786},
doi = {10.1371/journal.pone.0219786},
pmid = {31314793},
issn = {1932-6203},
abstract = {BACKGROUND: As population health and well-being are influenced by multiple factors that cut across sectoral boundaries, an intersectoral approach that acknowledges and leverages the multiple determinants, actors and sectors at play is increasingly seen as critical for achieving meaningful and lasting improvements. In this study, we utilize social network analysis (SNA) to characterize the intersectoral collaboration between the organizations working on maternal &amp; child health (MCH) and water &amp; sanitation (WASH) before and immediately after the implementation of HCL Foundation (HCLF)-funded HCL Samuday Project (2015-2017) in a rural block of Uttar Pradesh state, India. While SNA has been used to examine public health issues, few have used it monitor stakeholder relationships, intervene, improve and facilitate project implementation involving intersectoral partnerships, particularly in the context of a low-and middle-income countries.<br><br>METHOD: An organization-level SNA was conducted with 31 key informants from 24 organizations working on MCH and/or WASH in Kachhauna, Uttar Pradesh, India. Data were collected using face-to-face, semi-structured interviews between June and September 2017. Density, centrality and homophily were calculated to describe the network and a qualitative analysis was also conducted to identify the strengths and weaknesses of collaboration between organizations working on MCH and WASH.<br><br>RESULTS: Overall, our findings showed that the network of organizations working on MCH and WASH in Kachhauna grew in number since the implementation of Samuday. HCLF rapidly achieved centrality, thus positioning the organization to serve as a gatekeeper of information and enabling it to play a coordinator role within the network. Direct collaboration between other organizations working on MCH and WASH was low at both time points. Interviews with key informants indicated widespread interest in increasing interorganizational interactions and engagement throughout the network.<br><br>CONCLUSION: This study demonstrates the feasibility and practical application of SNA for projects like Samuday that involve intersectoral collaboration. It also provides lessons about the use of SNA with organizations as the unit of analysis and in the context of rural India, including challenges, practical considerations, and limitations.},
}
@article {pmid31314666,
year = {2019},
author = {Martínez-Medina, A and Fernández, I and Pescador, L and Romero-Puertas, MC and Pozo, MJ},
title = {Trichoderma harzianum triggers an early and transient burst of nitric oxide and the upregulation of PHYTOGB1 in tomato roots.},
journal = {Plant signaling &amp; behavior},
volume = {14},
number = {9},
pages = {1640564},
doi = {10.1080/15592324.2019.1640564},
pmid = {31314666},
issn = {1559-2324},
abstract = {We recently demonstrated that nitric oxide (NO) accumulation and PHYTOGB1 transcriptional regulation are early components of the regulatory pathway that is activated in tomato roots during the onset of the mycorrhizal symbiosis between Rhizophagus irregularis and tomato roots. We further showed that the mycorrhizal interaction was associated with a specific NO-related signature, different from that triggered by the pathogen Fusarium oxysporum. Here, we extend our investigation by exploring the NO- and PHYTOGB1-related root responses elicited by another root mutualistic endosymbiotic fungus: Trichoderma harzianum T-78. By using T-78 in vitro-grown cultures, we found that T-78 triggered an early and transient burst of NO in tomato roots during the first hours after the interaction. T-78 also elicited the early upregulation of PHYTOGB1, which was maintained during the analyzed timespan. By using glass-house bioassays, we found that in a well-established tomato-T-78 symbiosis, NO root levels were maintained at basal level while PHYTOGB1 expression remained upregulated. Our results demonstrate that the T-78 symbiosis is associated with a rapid and transient burst of NO in the host roots and the transcriptional activation of PHYTOGB1 from early stages of the interaction until the establishment of the symbiosis, most likely to control NO levels and favor the mutualistic symbiosis.},
}
@article {pmid31313020,
year = {2019},
author = {Liu, M and Soyano, T and Yano, K and Hayashi, M and Kawaguchi, M},
title = {ERN1 and CYCLOPS coordinately activate NIN signaling to promote infection thread formation in Lotus japonicus.},
journal = {Journal of plant research},
volume = {132},
number = {5},
pages = {641-653},
doi = {10.1007/s10265-019-01122-w},
pmid = {31313020},
issn = {1618-0860},
support = {22128006//Ministry of Education, Culture, Sports, Science and Technology/ ; 17H03702//Ministry of Education, Culture, Sports, Science and Technology/ ; 150574//Sumitomo Foundation/ ; },
abstract = {Legumes engage in symbiosis with nitrogen-fixing soil bacteria, collectively called rhizobia, under nitrogen-limited conditions. In many legumes, the root invasion of rhizobia is mediated by infection threads (ITs), tubular invaginations of the host cell wall and plasma membrane, developed from infection foci of deformed root hairs. IT formation is regulated by a series of signal transduction in host root. Nodulation signals activate the host transcription factor (TF), CYCLOPS, which directly induces expression of two TF genes, ERF REQUIRED FOR NODULATION1 (ERN1) and NODULE INCEPTION (NIN), essential for IT development. Here, we explored the relationship among these three symbiotic TF genes in the model legume Lotus japonicus and examined how their interplay contributes to IT formation. qRT-PCR analysis showed that NIN expression induced by rhizobial infection was attenuated in ern1-1, and further declined in cyclops-3 ern1-1. ERN1 overexpression led to induction of NIN expression in cyclops-3 ern1-1 in the presence of rhizobia. Thus, in addition to CYCLOPS, ERN1 is able to increase the NIN expression level depending on infection. Furthermore, consistent with this transcriptional hierarchy, ectopic expression of ERN1 as well as NIN suppressed the IT-deficient cyclops-3 phenotype, but ERN1 failed to confer ITs in the nin-2 root. However, the ern1-1 symbiotic epidermal phenotype was not suppressed by the NIN ectopic expression. The cyclops-3 ern1-1 double mutant was less sensitive to rhizobial infection than the single mutants and defective in the symbiotic root hair response at earlier stages. This more severe phenotype of the double mutant suggests a role for ERN1 that independent of the CYCLOPS-mediated transcriptional regulation. We conclude that ERN1 is involved in regulating NIN expression in addition to CYCLOPS, and these TFs coordinately promote the symbiotic root hair response and IT development. Our data help to reveal the extensive role of ERN1 in root nodule symbiosis signaling.},
}
@article {pmid31311876,
year = {2019},
author = {Xie, XG and Zhang, FM and Yang, T and Chen, Y and Li, XG and Dai, CC},
title = {Endophytic Fungus Drives Nodulation and N2 Fixation Attributable to Specific Root Exudates.},
journal = {mBio},
volume = {10},
number = {4},
pages = {},
doi = {10.1128/mBio.00728-19},
pmid = {31311876},
issn = {2150-7511},
abstract = {Endophytic fungi play important roles in the modification of ecosystem productivity; however, the underlying mechanisms are only partly understood. A 2-year field plot experiment verified that the endophytic fungus Phomopsis liquidambaris increased peanut (Arachis hypogaea L.) yields and significantly increased nodulation and N2 fixation regardless of whether N fertilizers were added. Root exudates collected from P. liquidambaris-colonized plants significantly improved nodulation and N2 fixation. Rhizosphere stimulation experiments further showed that colonized root exudates had significantly decreased soil nitrate (NO3-) concentrations, with decreased abundance and diversity of ammonia oxidizing archaea (AOA). In contrast, the abundance and diversity of diazotrophs significantly increased, and most diazotrophs identified were peanut nodulation-related strains (Bradyrhizobium sp.). P. liquidambaris symbiosis increased the expression of phenolic and flavonoid synthesis-related genes, and the derived phenolics and flavonoids could effectively increase the chemotaxis, biofilm formation, and nodC gene expression (nodulation-related biological processes) of the Bradyrhizobium strain. Metabolic pattern analysis showed that phenolics and flavonoids are more likely to accumulate to higher levels in the rhizosphere soil of peanuts colonized with P. liquidambaris Finally, a synthetic root exudate experiment further confirmed the underlying mechanisms for the P. liquidambaris-induced improvement in nodulation and N2 fixation, i.e., that the specific root exudates derived from P. liquidambaris colonization decrease nitrate concentration and increase the population and biological activities of peanut nodulation-related Bradyrhizobium species, which beneficially enhance peanut-Bradyrhizobium interactions. Therefore, this study is the first to provide new insight into a positive relationship between an exotic endophytic fungus, crop nodulation, and N2 fixation increase.IMPORTANCE Endophytic fungi play an important role in balancing the ecosystem and boosting host growth; however, the underpinning mechanisms remain poorly understood. Here, we found that endophytic fungal colonization with P. liquidambaris significantly increased the productivity, nodulation, and N2 fixation of peanuts through the secretion of specific root exudates. We provide a reasonable mechanism explaining how P. liquidambaris promotes peanut nodulation and N2 fixation, whereby the specific root exudates produced by P. liquidambaris colonization decrease rhizosphere soil nitrate (NO3-) and increase the population and biological activities of peanut-nodulating-related Bradyrhizobium strains, which is beneficial to enhancing the peanut-Bradyrhizobium symbiotic interaction. Our study provides reliable empirical evidence to show the mechanism of how an exotic endophytic fungus drives an increase in nodulation and N2 fixation, which will be helpful in erecting a resource-efficient and sustainable agricultural system.},
}
@article {pmid31310638,
year = {2019},
author = {Sinnesael, A and Leroux, O and Janssens, SB and Smets, E and Panis, B and Verstraete, B},
title = {Is the bacterial leaf nodule symbiosis obligate for Psychotria umbellata? The development of a Burkholderia-free host plant.},
journal = {PloS one},
volume = {14},
number = {7},
pages = {e0219863},
doi = {10.1371/journal.pone.0219863},
pmid = {31310638},
issn = {1932-6203},
abstract = {BACKGROUND &amp; AIMS: The bacterial leaf nodule symbiosis is an interaction where bacteria are housed in specialised structures in the leaves of their plant host. In the Rubiaceae plant family, host plants interact with Burkholderia bacteria. This interaction might play a role in the host plant defence system. It is unique due to its high specificity; the vertical transmission of the endophyte to the next generation of the host plant; and its supposedly obligatory character. Although previous attempts have been made to investigate this obligatory character by developing Burkholderia-free plants, none have succeeded and nodulating plants were still produced. In order to investigate the obligatory character of this endosymbiosis, our aims were to develop Burkholderia-free Psychotria umbellata plants and to investigate the effect of the absence of the endophytes on the host in a controlled environment.<br><br>METHODS: The Burkholderia-free plants were obtained via embryo culture, a plant cultivation technique. In order to analyse the endophyte-free status, we screened the plants morphologically, microscopically and molecularly over a period of three years. To characterise the phenotype and growth of the in vitro aposymbiotic plants, we compared the growth of the Burkholderia-free plants to the nodulating plants under the same in vitro conditions.<br><br>KEY RESULTS: All the developed plants were Burkholderia-free and survived in a sterile in vitro environment. The growth analysis showed that plants without endophytes had a slower development.<br><br>CONCLUSIONS: Embryo culture is a cultivation technique with a high success rate for the development of Burkholderia-free plants of P. umbellata. The increased growth rate in vitro when the specific endophyte is present cannot be explained by possible benefits put forward in previous studies. This might indicate that the benefits of the endosymbiosis are not yet completely understood.},
}
@article {pmid31307572,
year = {2019},
author = {Bonfante, P},
title = {Algae and fungi move from the past to the future.},
journal = {eLife},
volume = {8},
number = {},
pages = {},
doi = {10.7554/eLife.49448},
pmid = {31307572},
issn = {2050-084X},
abstract = {The ability of photosynthetic algae to enter the hyphae of a soil fungus could tell us more about the evolution of these species and their potential for applications in the production of biofuel.},
}
@article {pmid31307571,
year = {2019},
author = {Du, ZY and Zienkiewicz, K and Vande Pol, N and Ostrom, NE and Benning, C and Bonito, GM},
title = {Algal-fungal symbiosis leads to photosynthetic mycelium.},
journal = {eLife},
volume = {8},
number = {},
pages = {},
doi = {10.7554/eLife.47815},
pmid = {31307571},
issn = {2050-084X},
support = {DE-FG02-91ER20021//U.S. Department of Energy/International ; DE-SC0018409//U.S. Department of Energy/International ; DE-FC02-07ER64494//U.S. Department of Energy/International ; FP7/2007-2013 n° [627266]//European Union Seventh Framework Programme/International ; DEB 1737898//National Science Foundation/International ; },
abstract = {Mutualistic interactions between free-living algae and fungi are widespread in nature and are hypothesized to have facilitated the evolution of land plants and lichens. In all known algal-fungal mutualisms, including lichens, algal cells remain external to fungal cells. Here, we report on an algal-fungal interaction in which Nannochloropsis oceanica algal cells become internalized within the hyphae of the fungus Mortierella elongata. This apparent symbiosis begins with close physical contact and nutrient exchange, including carbon and nitrogen transfer between fungal and algal cells as demonstrated by isotope tracer experiments. This mutualism appears to be stable, as both partners remain physiologically active over months of co-cultivation, leading to the eventual internalization of photosynthetic algal cells, which persist to function, grow and divide within fungal hyphae. Nannochloropsis and Mortierella are biotechnologically important species for lipids and biofuel production, with available genomes and molecular tool kits. Based on the current observations, they provide unique opportunities for studying fungal-algal mutualisms including mechanisms leading to endosymbiosis.},
}
@article {pmid31306759,
year = {2019},
author = {Chen, H and Wang, M and Zhang, H and Wang, H and Lv, Z and Zhou, L and Zhong, Z and Lian, C and Cao, L and Li, C},
title = {An LRR-domain containing protein identified in Bathymodiolus platifrons serves as intracellular recognition receptor for the endosymbiotic methane-oxidation bacteria.},
journal = {Fish &amp; shellfish immunology},
volume = {93},
number = {},
pages = {354-360},
doi = {10.1016/j.fsi.2019.07.032},
pmid = {31306759},
issn = {1095-9947},
abstract = {As domain species in seep and vent ecosystem, Bathymodioline mussels has been regarded as a model organism in investigating deep sea chemosymbiosis. However, mechanisms underlying their symbiosis with chemosynthetic bacteria, especially how the host recognizes symbionts, have remained largely unsolved. In the present study, a modified pull-down assay was conducted using enriched symbiotic methane-oxidation bacteria as bait and gill proteins of Bathymodiolus platifrons as a target to isolate pattern recognition receptors involved in the immune recognition of symbionts. As a result, a total of 47 proteins including BpLRR-1 were identified from the pull-down assay. It was found that complete cDNA sequence of BpLRR-1 contained an open reading frame of 1479 bp and could encode a protein of 492 amino acid residues with no signal peptide or transmembrane region but eight LRR motif and two EFh motif. The binding patterns of BpLRR-1 against microbial associated molecular patterns were subsequently investigated by surface plasmon resonance analysis and LPS pull-down assay. Consequently, BpLRR-1 was found with high binding affinity with LPS and suggested as a key molecule in recognizing symbionts. Besides, transcripts of BpLRR-1 were found decreased significantly during symbiont depletion assay yet increased rigorously during symbionts or nonsymbiotic Vibrio alginolyticus challenge, further demonstrating its participation in the chemosynthetic symbiosis. Collectively, these results suggest that BpLRR-1 could serve as an intracellular recognition receptor for the endosymbionts, providing new hints for understanding the immune recognition in symbiosis of B. platifrons.},
}
@article {pmid31306482,
year = {2019},
author = {Ntoukakis, V and Gifford, ML},
title = {Plant-microbe interactions: tipping the balance.},
journal = {Journal of experimental botany},
volume = {},
number = {},
pages = {},
doi = {10.1093/jxb/erz321},
pmid = {31306482},
issn = {1460-2431},
}
@article {pmid31304965,
year = {2019},
author = {Tian, H and Wang, R and Li, M and Dang, H and Solaiman, ZM},
title = {Molecular signal communication during arbuscular mycorrhizal formation induces significant transcriptional reprogramming of wheat (Triticum aestivum L.) roots.},
journal = {Annals of botany},
volume = {},
number = {},
pages = {},
doi = {10.1093/aob/mcz119},
pmid = {31304965},
issn = {1095-8290},
abstract = {BACKGROUND AND AIMS: Arbuscular mycorrhizal (AM) symbiosis initiates with molecular signal communication (MSC) between AM fungi and the roots of the host plant. We aimed to test the hypothesis that the transcriptional profiles of wheat roots can be changed significantly by AM symbiotic signals, without direct contact.<br><br>METHODS: Non-mycorrhizal (NM) and MSC treatments involved burying filter membrane bags containing sterilized and un-sterilized inoculum of the AM fungus Rhizophagus irregularis, respectively. The bags physically separated roots and AM structures but allowed molecular signals to pass through. Extracted RNA from wheat roots was sequenced by high-throughput sequencing.<br><br>RESULTS: Shoot total nitrogen and phosphorus content of wheat plants was decreased by the MSC treatment. A total of 2,360 differentially expressed genes (DEGs), including 1,888 up-regulated DEGs and 472 down-regulated DEGs were found dominantly distributed on the 2A, 2B, 2D, 3B, 5B and 5D chromosomes. The expression of 59 and 121 genes was greatly up- and down-regulated, respectively. Only a portion of DEGs could be enriched into known terms during gene ontology analysis, and were mostly annotated to 'catalytic activity', 'protein metabolic process' and 'membrane' in the molecular function, biological process and cellular component ontology, respectively. More than 120 genes that may be involved in key processes during AM symbiosis development were regulated at the pre-physical contact stages.<br><br>CONCLUSIONS: The transcriptional profiles of wheat roots can be changed dramatically by MSC. Much of the information provided by our study is of great importance for understanding the mechanisms underlying the development of AM symbiosis.},
}
@article {pmid31302359,
year = {2019},
author = {Oliva, G and Ángeles, R and Rodríguez, E and Turiel, S and Naddeo, V and Zarra, T and Belgiorno, V and Muñoz, R and Lebrero, R},
title = {Comparative evaluation of a biotrickling filter and a tubular photobioreactor for the continuous abatement of toluene.},
journal = {Journal of hazardous materials},
volume = {380},
number = {},
pages = {120860},
doi = {10.1016/j.jhazmat.2019.120860},
pmid = {31302359},
issn = {1873-3336},
abstract = {The negative effects of volatile organic compounds (VOCs) on humans' health and the environment have boosted the enforcement of regulations, resulting in the need of effective and environmentally friendly off-gas treatment technologies. In this work, the synergism between microalgae and bacteria was investigated as a sustainable platform to enhance the biological degradation of toluene, herein selected as a model VOC. An innovative algal-bacterial tubular photobioreactor (TPBR) was systematically compared with a conventional biotrickling filter (BTF). The BTF supported average removal efficiencies close to those obtained in the TPBR (86 ± 9% and 88 ± 4%, respectively) at the highest inlet load (∼23 g m3 h-1) and lowest gas residence time (0.75 min). However, the BTF was more sensitive towards the accumulation of secondary metabolites. In this regard, photosynthetic O2 supplementation (resulting in dissolved oxygen concentrations of ∼7.3 mg O2 L-1) and CO2 consumption by microalgae (which reduced the impact of acidification) enhanced toluene abatement performance and process stability.},
}
@article {pmid31296160,
year = {2019},
author = {Richards, S and Rose, LE},
title = {The evolutionary history of LysM-RLKs (LYKs/LYRs) in wild tomatoes.},
journal = {BMC evolutionary biology},
volume = {19},
number = {1},
pages = {141},
doi = {10.1186/s12862-019-1467-3},
pmid = {31296160},
issn = {1471-2148},
abstract = {BACKGROUND: The LysM receptor-like kinases (LysM-RLKs) are important to both plant defense and symbiosis. Previous studies described three clades of LysM-RLKs: LysM-I/LYKs (10+ exons per gene and containing conserved kinase residues), LysM-II/LYRs (1-5 exons per gene, lacking conserved kinase residues), and LysM-III (two exons per gene, with a kinase unlike other LysM-RLK kinases and restricted to legumes). LysM-II gene products are presumably not functional as conventional receptor kinases, but several are known to operate in complexes with other LysM-RLKs. One aim of our study was to take advantage of recently mapped wild tomato transcriptomes to evaluate the evolutionary history of LysM-RLKs within and between species. The second aim was to place these results into a broader phylogenetic context by integrating them into a sequence analysis of LysM-RLKs from other functionally well-characterized model plant species. Furthermore, we sought to assess whether the Group III LysM-RLKs were restricted to the legumes or found more broadly across Angiosperms.<br><br>RESULTS: Purifying selection was found to be the prevailing form of natural selection within species at LysM-RLKs. No signatures of balancing selection were found in species-wide samples of two wild tomato species. Most genes showed a greater extent of purifying selection in their intracellular domains, with the exception of SlLYK3 which showed strong purifying selection in both the extracellular and intracellular domains in wild tomato species. The phylogenetic analysis did not reveal a clustering of microbe/functional specificity to groups of closely related proteins. We also discovered new putative LysM-III genes in a range of Rosid species, including Eucalyptus grandis.<br><br>CONCLUSIONS: The LysM-III genes likely originated before the divergence of E. grandis from other Rosids via a fusion of a Group II LysM triplet and a kinase from another RLK family. SlLYK3 emerges as an especially interesting candidate for further study due to the high protein sequence conservation within species, its position in a clade of LysM-RLKs with distinct LysM domains, and its close evolutionary relationship with LYK3 from Arabidopsis thaliana.},
}
@article {pmid31295658,
year = {2019},
author = {Amirikhah, R and Etemadi, N and Sabzalian, MR and Nikbakht, A and Eskandari, A},
title = {Physiological consequences of gamma ray irradiation in tall fescue with elimination potential of Epichloë fungal endophyte.},
journal = {Ecotoxicology and environmental safety},
volume = {182},
number = {},
pages = {109412},
doi = {10.1016/j.ecoenv.2019.109412},
pmid = {31295658},
issn = {1090-2414},
abstract = {Perennial plants and their associated microorganisms grow in the areas that may be contaminated with long-lived gamma-emitting radionuclides. This will induce gamma stress response in plants and their accompanying microorganisms. The present work investigated the growth and physiological responses of Epichloe endophyte infected tall fescue to gamma radiation, as well as whether the endophyte could persist and infect the host plant once exposed to gamma radiation. Seeds of Iranian native genotype of 75B+ of tall fescue were exposed to different doses, including 5.0, 10.0, 15.0, 20.0, 30.0 and 40.0 krad of gamma ray from a 60Co source. Irradiated and unirradiated seeds were sown in pots and grown under controlled conditions in the greenhouse. The growth and physiological parameters associated with plant tolerance to oxidative stress of host plants, as well as endophytic infection frequency (% of plants infected) and intensity (mean number of endophytic hyphae per the field of view), were examined in 3 months-old seedlings. The results indicated that all gamma radiation doses (except 5.0 kr) significantly reduced the height and survival percentage of the host plant. Days to the emergence of seedling increased gradually as gamma doses rose. A dose-rate dependent induction was seen for photosynthetic pigments and proline content. Malondialdehyde (MDA) content grew with elevation of irradiation doses. Depending on the dose and time, the activities of antioxidant enzymes in the host plant responded differently to gamma radiation. Gamma radiation altered the enzyme activities with sever decline in SOD and CAT activities. However, it had barely any effect on in APX and POD activities. The results also revealed that the persistence and intensity of endophyte were affected after gamma-ray irradiation. The initial percentage of tall fescue seeds infected with the endophyte was 91% in un-irradiated seeds. Presence of the viable endophyte started to decline significantly (23%) at 5.0 kr of gamma radiation. A dramatic reduction in the presence and intensity of endophyte occurred at 10.0 to 40.0 kr intensities. Gamma radiation × trait (GT)-biplot analysis indicated positive correlations between the endophyte symbiosis and antioxidant enzyme activities. Also, negative correlations were observed between the endophyte and MDA content in the host plant. Our results suggest that radiation stress (doses over 5.0 kr) caused reduction in the growth and antioxidant enzyme activities of the host plant that accompanied by a dramatic reduction in the persistence and intensity of endophyte fungi. Our findings have provided the basic information for future studies on the effect of gamma irradiation on the interaction between endophytic fungi and its host plant.},
}
@article {pmid31292767,
year = {2019},
author = {Ogura-Tsujita, Y and Yamamoto, K and Hirayama, Y and Ebihara, A and Morita, N and Imaichi, R},
title = {Fern gametophytes of Angiopteris lygodiifolia and Osmunda japonica harbor diverse Mucoromycotina fungi.},
journal = {Journal of plant research},
volume = {132},
number = {5},
pages = {581-588},
doi = {10.1007/s10265-019-01121-x},
pmid = {31292767},
issn = {1618-0860},
support = {17K07536//Japan Society for the Promotion of Science/ ; 18K06391//Japan Society for the Promotion of Science/ ; },
abstract = {Mycorrhizal symbiosis between plants and fungi is ubiquitous, and has been played key roles in plant terrestrialization and diversification. Although arbuscular mycorrhizal (AM) symbioses with Glomeromycotina fungi have long been recognized as both ancient and widespread symbionts, recent studies showed that Mucoromycotina fungi were also ancestral symbionts and would thus be expected to co-exist with many land plants. To explore whether Mucoromycotina colonize fern gametophytes, we subjected fungal associations with gametophytes of two distantly related ferns, Angiopteris lygodiifolia (Marattiales) and Osmunda japonica (Osmundales), to molecular analysis. Direct PCR amplification from intracellular hyphal coils was also performed. We detected Mucoromycotina sequences in the gametophytes of A. lygodiifolia and O. japonica at rates of 41% (7/17) and 50% (49/98) of gametophytes, respectively, and assigned them to 10 operational taxonomic units of Endogonales lineages. In addition, we used AM fungal-specific primers and detected Glomeromycotina sequences in all individuals examined. The results suggest that Glomeromycotina and Mucoromycotina colonized fern gametophytes simultaneously. We found that Mucoromycotina were present in fern gametophytes of Marratiales and Osmundales, which implies that a variety of fern taxa have Mucoromycotina associations.},
}
@article {pmid31291473,
year = {2019},
author = {Montesinos-Navarro, A and Valiente-Banuet, A and Verdú, M},
title = {Plant facilitation through mycorrhizal symbiosis is stronger between distantly related plant species.},
journal = {The New phytologist},
volume = {},
number = {},
pages = {},
doi = {10.1111/nph.16051},
pmid = {31291473},
issn = {1469-8137},
support = {FPDI-2013-16266//Consejo Superior de Investigaciones Científicas/ ; IJCI-2015-23498//Consejo Superior de Investigaciones Científicas/ ; RTI2018-099672-J-I00//Consejo Superior de Investigaciones Científicas/ ; GV/2016/187//Generalitat Valenciana/ ; PROMETEO/2016/021//Generalitat Valenciana/ ; CGL2016-81706-REDT//Ecometas excellence network/ ; P417RT0228//CYTED Ciencia y Tecnología para el Desarrollo/ ; 3975-4849//British Ecological Society/ ; IN-210117//Dirección General de Asuntos del Personal Académico, Universidad Nacional Autónoma de México/ ; IN-213414-3//Dirección General de Asuntos del Personal Académico, Universidad Nacional Autónoma de México/ ; },
abstract = {The tendency of closely related plant species to share natural enemies has been suggested to limit their co-occurrence and performance, but we lack a deep understanding on how mutualistic interactions such as the mycorrhizal symbiosis affect plant-plant interactions depending on the phylogenetic relatedness of the interacting plants. We hypothesise that the effect of the mycorrhizal symbiosis on plant-plant facilitative interactions depends on the phylogenetic distance between the nurse and facilitated plants. A recently published meta-analysis compiled the strength of plant facilitative interactions in the presence or absence (or reduced abundance) of mycorrhizal fungi. We use phylogenetically informed Bayesian linear models to test whether the effect size is influenced by the phylogenetic distance between the plant species involved in each plant facilitative interaction. Conspecific facilitative interactions are more strongly enhanced by mycorrhizal fungi than interactions between closely related species. In heterospecific interactions, the effect of the mycorrhizal symbiosis on plant facilitation increases with the phylogenetic distance between the nurse and facilitated plant species. Our result showing that the effect of mycorrhizal symbiosis on the facilitation interactions between plants depends on their phylogenetic relatedness provides new mechanisms to understand how facilitation is assembling ecological communities.},
}
@article {pmid31291312,
year = {2019},
author = {Marqués-Gálvez, JE and Morte, A and Navarro-Ródenas, A and García-Carmona, F and Pérez-Gilabert, M},
title = {Purification and characterization of Terfezia claveryi TcCAT-1, a desert truffle catalase upregulated in mycorrhizal symbiosis.},
journal = {PloS one},
volume = {14},
number = {7},
pages = {e0219300},
doi = {10.1371/journal.pone.0219300},
pmid = {31291312},
issn = {1932-6203},
abstract = {Terfezia claveryi Chatin is a mycorrhizal fungus that forms ectendomycorrhizal associations with plants of Helianthemum genus. Its appreciated edibility and drought resistance make this fungus a potential alternative crop in arid and semiarid areas of the Mediterranean region. In order to increase the knowledge about the biology of this fungus in terms of mycorrhiza formation and response to drought stress, a catalase from T. claveryi (TcCAT-1) has been purified to apparent homogeneity and biochemically characterized; in addition, the expression pattern of this enzyme during different stages of T. claveryi biological cycle and under drought stress conditions are reported. The results obtained, together with the phylogenetic analysis and homology modeling, indicate that TcCAT-1 is a homotetramer large subunit size monofunctional-heme catalase belonging to Clade 2. The highest expression of this enzyme occurs in mature mycorrhiza, revealing a possible role in mycorrhiza colonization, but it is not upregulated under drought stress. However, the H2O2 content of mycorrhizal plants submitted to drought stress is lower than in well watered treatments, suggesting that mycorrhization improves the plant's oxidative stress response, although not via TcCAT-1 upregulation.},
}
@article {pmid31288964,
year = {2019},
author = {Uroz, S and Courty, PE and Oger, P},
title = {Plant Symbionts Are Engineers of the Plant-Associated Microbiome.},
journal = {Trends in plant science},
volume = {},
number = {},
pages = {},
doi = {10.1016/j.tplants.2019.06.008},
pmid = {31288964},
issn = {1878-4372},
abstract = {Plants interact throughout their lives with environmental microorganisms. These interactions determine plant development, nutrition, and fitness in a dynamic and stressful environment, forming the basis for the holobiont concept in which plants and plant-associated microbes are not considered as independent entities but as a single evolutionary unit. A primary open question concerns whether holobiont structure is shaped by its microbial members or solely by the plant. Current knowledge of plant-microbe interactions argues that the establishment of symbiosis directly and indirectly conditions the plant-associated microbiome. We propose to define the impact of the symbiont on the plant microbiome as the 'symbiosis cascade effect', in which the symbionts and their plant host jointly shape the plant microbiome.},
}
@article {pmid31287538,
year = {2019},
author = {Suzuki, N},
title = {Glycan diversity in the course of vertebrate evolution.},
journal = {Glycobiology},
volume = {29},
number = {9},
pages = {625-644},
doi = {10.1093/glycob/cwz038},
pmid = {31287538},
issn = {1460-2423},
abstract = {Vertebrates are estimated to have arisen over 500 million years ago in the Cambrian Period. Species that survived the Big Five extinction events at a global scale underwent repeated adaptive radiations along with habitat expansions from the sea to the land and sky. The development of the endoskeleton and neural tube enabled more complex body shapes. At the same time, vertebrates became suitable for the invasion and proliferation of foreign organisms. Adaptive immune systems were acquired for responses to a wide variety of pathogens, and more sophisticated systems developed during the evolution of mammals and birds. Vertebrate glycans consist of common core structures and various elongated structures, such as Neu5Gc, Galα1-3Gal, Galα1-4Gal, and Galβ1-4Gal epitopes, depending on the species. During species diversification, complex glycan structures were generated, maintained or lost. Whole-genome sequencing has revealed that vertebrates harbor numerous and even redundant glycosyltransferase genes. The production of various glycan structures is controlled at the genetic level in a species-specific manner. Because cell surface glycans are often targets of bacterial and viral infections, glycan structural diversity is presumed to be protective against infections. However, the maintenance of apparently redundant glycosyltransferase genes and investment in species-specific glycan structures, even in higher vertebrates with highly developed immune systems, are not well explained. This fact suggests that glycans play important roles in unknown biological processes.},
}
@article {pmid31287368,
year = {2019},
author = {Liu, X and Xie, Z and Zhang, H},
title = {Inactivation of the phosphatase CheZ alters cell-surface properties of Azorhizobium caulinodans ORS571 and symbiotic association with Sesbania rostrata.},
journal = {Molecular plant-microbe interactions : MPMI},
volume = {},
number = {},
pages = {},
doi = {10.1094/MPMI-05-19-0143-R},
pmid = {31287368},
issn = {0894-0282},
abstract = {Azorhizobium caulinodans can form root and stem nodules with the host plant Sesbania rostrata. The role of the CheZ phosphatase in the A. caulinodans chemotaxis pathway was previously explored using the non-chemotactic cheZ mutant strain (AC601). This mutant displayed stronger attachment to the root surface, enhancing early colonization but this did not result into increased nodulation efficiency. In this study, we further investigated the role of CheZ in the interaction between ORS571 and the roots of its host plant. By tracking long-term colonization dynamic of cheZ mutant marked with LacZ, we found a decrease of colonization of the cheZ mutant during this process. Furthermore, cheZ mutant could not spread on root surface freely and was gradually outcompeted by the wild type in original colonization sites. Quantitative reverse transcription-PCR analyses showed that exp genes encoding exopolysaccharides synthesis, including oac3, were highly expressed in cheZ mutant. Construction of a strain carrying a deletion of both cheZ and oac3 resulted in a mutant strain defective in the colonization process to the same extent as found with the oac3 single mutant strain. This result suggested that the enhanced colonization of the cheZ mutant may be achieved through regulating the formation of EPS. This shows the importance of the chemotactic proteins in the interaction between rhizobia and host plant, and expands our understanding about the symbiosis interaction between rhizobium and host plant.},
}
@article {pmid31285778,
year = {2019},
author = {Viennois, E and Chassaing, B and Tahsin, A and Pujada, A and Wang, L and Gewirtz, AT and Merlin, D},
title = {Host-derived fecal microRNAs can indicate gut microbiota healthiness and ability to induce inflammation.},
journal = {Theranostics},
volume = {9},
number = {15},
pages = {4542-4557},
doi = {10.7150/thno.35282},
pmid = {31285778},
issn = {1838-7640},
support = {R01 DK099071/DK/NIDDK NIH HHS/United States ; I01 BX002526/BX/BLRD VA/United States ; R01 DK107739/DK/NIDDK NIH HHS/United States ; R01 DK071594/DK/NIDDK NIH HHS/United States ; IK6 BX004476/BX/BLRD VA/United States ; R01 DK116306/DK/NIDDK NIH HHS/United States ; },
abstract = {Disruption of intestine-microbiota symbiosis can result in chronic gut inflammation. We hypothesize that assessing the initial inflammatory potential of the microbiota in patients is essential and that host-derived miRNAs, which can be found in feces, could fulfill this function. We investigated whether the gut microbiota composition impacts the fecal miRNA profile and thereby indicates its ability to influence intestinal inflammation. Methods: We used high-throughput qPCR to compare fecal miRNA profile between germ-free and conventional mice. Conventionalization of germfree mice by various colitogenic and non-colitogenic microbiotas (IL10-/- and TLR5-/- associated microbiota) was performed. Results: We identified 12 fecal miRNAs impacted by the presence of a microbiota. Conventionalization of germfree mice by various colitogenic and non-colitogenic microbiotas associated with the development of intestinal inflammation (IL10-/- and TLR5-/- associated microbiota) yielded distinctively altered fecal miRNA profiles compared to that of mice receiving a &quot;healthy&quot; microbiota. Correlation analysis revealed the existence of interactions between the 12 abovementioned miRNAs and specific microbiota members. Conclusion: These results showed that fecal miRNA profile can be differentially and specifically impacted by microbiota composition, and that miRNA could importantly serve as markers of the colitogenic potential of the microbiota. This is particularly relevant to assess individual state of the microbiota in patients with dysbiosis-related disorders, such as IBD and potentially determine their ability to respond to therapeutics.},
}
@article {pmid31285337,
year = {2019},
author = {Greenlon, A and Chang, PL and Damtew, ZM and Muleta, A and Carrasquilla-Garcia, N and Kim, D and Nguyen, HP and Suryawanshi, V and Krieg, CP and Yadav, SK and Patel, JS and Mukherjee, A and Udupa, S and Benjelloun, I and Thami-Alami, I and Yasin, M and Patil, B and Singh, S and Sarma, BK and von Wettberg, EJB and Kahraman, A and Bukun, B and Assefa, F and Tesfaye, K and Fikre, A and Cook, DR},
title = {Global-level population genomics reveals differential effects of geography and phylogeny on horizontal gene transfer in soil bacteria.},
journal = {Proceedings of the National Academy of Sciences of the United States of America},
volume = {116},
number = {30},
pages = {15200-15209},
doi = {10.1073/pnas.1900056116},
pmid = {31285337},
issn = {1091-6490},
abstract = {Although microorganisms are known to dominate Earth's biospheres and drive biogeochemical cycling, little is known about the geographic distributions of microbial populations or the environmental factors that pattern those distributions. We used a global-level hierarchical sampling scheme to comprehensively characterize the evolutionary relationships and distributional limitations of the nitrogen-fixing bacterial symbionts of the crop chickpea, generating 1,027 draft whole-genome sequences at the level of bacterial populations, including 14 high-quality PacBio genomes from a phylogenetically representative subset. We find that diverse Mesorhizobium taxa perform symbiosis with chickpea and have largely overlapping global distributions. However, sampled locations cluster based on the phylogenetic diversity of Mesorhizobium populations, and diversity clusters correspond to edaphic and environmental factors, primarily soil type and latitude. Despite long-standing evolutionary divergence and geographic isolation, the diverse taxa observed to nodulate chickpea share a set of integrative conjugative elements (ICEs) that encode the major functions of the symbiosis. This symbiosis ICE takes 2 forms in the bacterial chromosome-tripartite and monopartite-with tripartite ICEs confined to a broadly distributed superspecies clade. The pairwise evolutionary relatedness of these elements is controlled as much by geographic distance as by the evolutionary relatedness of the background genome. In contrast, diversity in the broader gene content of Mesorhizobium genomes follows a tight linear relationship with core genome phylogenetic distance, with little detectable effect of geography. These results illustrate how geography and demography can operate differentially on the evolution of bacterial genomes and offer useful insights for the development of improved technologies for sustainable agriculture.},
}
@article {pmid31285273,
year = {2019},
author = {Pederson, ERA and Warshan, D and Rasmussen, U},
title = {Genome Sequencing of Pleurozium schreberi: The Assembled and Annotated Draft Genome of a Pleurocarpous Feather Moss.},
journal = {G3 (Bethesda, Md.)},
volume = {9},
number = {9},
pages = {2791-2797},
doi = {10.1534/g3.119.400279},
pmid = {31285273},
issn = {2160-1836},
abstract = {The pleurocarpous feather moss Pleurozium schreberi is a ubiquitous moss species which plays a fundamental role in many terrestrial ecosystems, for instance within the boreal forest, the Earth's largest terrestrial biome, this species plays a significant role in driving ecosystem nitrogen and carbon inputs and fluxes. By hosting dinitrogen (N2)-fixing cyanobacteria, the moss-cyanobacteria symbiosis constitutes the main nitrogen input into the ecosystem and by the high productivity and the low decomposability of the moss litter, Pschreberi contributes significantly to build-up soil organic matter, and therefore long-term C sequestration. Knowledge on P. schreberi genome will facilitate the development of 'omics' and system's biology approaches to gain a more complete understanding of the physiology and ecological adaptation of the moss and the mechanisms underpinning the establishment of the symbiosis. Here we present the de novo assembly and annotation of P. schreberi genome that will help investigating these questions. The sequencing was performed using the HiSeq X platform with Illumina paired-end and mate-pair libraries prepared with CTAB extracted DNA. In total, the assembled genome was approximately 318 Mb, while repetitive elements account for 28.42% of the genome and 15,992 protein-coding genes were predicted from the genome, of which 84.23% have been functionally annotated. We anticipate that the genomic data generated will constitute a significant resource to study ecological and evolutionary genomics of P. schreberi, and will be valuable for evo-devo investigations as well as our understanding of the evolution of land plants by providing the genome of a pleurocarpous moss.},
}
@article {pmid31283433,
year = {2019},
author = {Thapa, SP and Davis, EW and Lyu, Q and Weisberg, AJ and Stevens, DM and Clarke, CR and Coaker, G and Chang, JH},
title = {The Evolution, Ecology, and Mechanisms of Infection by Gram-Positive, Plant-Associated Bacteria.},
journal = {Annual review of phytopathology},
volume = {57},
number = {},
pages = {341-365},
doi = {10.1146/annurev-phyto-082718-100124},
pmid = {31283433},
issn = {1545-2107},
abstract = {Gram-positive bacteria are prominent members of plant-associated microbial communities. Although many are hypothesized to be beneficial, some are causative agents of economically important diseases of crop plants. Because the features of Gram-positive bacteria are fundamentally different relative to those of Gram-negative bacteria, the evolution and ecology as well as the mechanisms used to colonize and infect plants also differ. Here, we discuss recent advances in our understanding of Gram-positive, plant-associated bacteria and provide a framework for future research directions on these important plant symbionts.},
}
@article {pmid31283425,
year = {2019},
author = {Apprill, A},
title = {The Role of Symbioses in the Adaptation and Stress Responses of Marine Organisms.},
journal = {Annual review of marine science},
volume = {},
number = {},
pages = {},
doi = {10.1146/annurev-marine-010419-010641},
pmid = {31283425},
issn = {1941-0611},
abstract = {Ocean ecosystems are experiencing unprecedented rates of climate and anthropogenic change, which can often initiate stress in marine organisms. Symbioses, or associations between different organisms, are plentiful in the ocean and could play a significant role in facilitating organismal adaptations to stressful ocean conditions. This article reviews current knowledge about the role of symbiosis in marine organismal acclimation and adaptation. It discusses stress and adaptations in symbioses from coral reef ecosystems, which are among the most affected environments in the ocean, including the relationships between corals and microalgae, corals and bacteria, anemones and clownfish, and cleaner fish and client fish. Despite the importance of this subject, knowledge of how marine organisms adapt to stress is still limited, and there are vast opportunities for research and technological development in this area. Attention to this subject will enhance our understanding of the capacity of symbioses to alleviate organismal stress in the oceans. Expected final online publication date for the Annual Review of Marine Science Volume 12 is January 3, 2020. Please see http://www.annualreviews.org/page/journal/pubdates for revised estimates.},
}
@article {pmid31283172,
year = {2019},
author = {Niehs, SP and Dose, B and Scherlach, K and Pidot, SJ and Stinear, TP and Hertweck, C},
title = {Genome Mining Reveals Endopyrroles from a Nonribosomal Peptide Assembly Line Triggered in Fungal-Bacterial Symbiosis.},
journal = {ACS chemical biology},
volume = {14},
number = {8},
pages = {1811-1818},
doi = {10.1021/acschembio.9b00406},
pmid = {31283172},
issn = {1554-8937},
abstract = {The bacterial endosymbiont (Burkholderia rhizoxinica) of the rice seedling blight fungus (Rhizopus microsporus) harbors a large number of cryptic biosynthesis gene clusters. Genome mining and sequence similarity networks based on an encoded nonribosomal peptide assembly line and the associated pyrrole-forming enzymes in the symbiont indicated that the encoded metabolites are unique among a large number of tentative pyrrole natural products in diverse and unrelated bacterial phyla. By performing comparative metabolic profiling using a mutant generated with an improved pheS Burkholderia counterselection marker, we found that the symbionts' biosynthetic pathway is mainly activated under salt stress and exclusively in symbiosis with the fungal host. The cryptic metabolites were fully characterized as novel pyrrole-substituted depsipeptides (endopyrroles). A broader survey showed that endopyrrole production is a hallmark of geographically distant endofungal bacteria, which produce the peptides solely under symbiotic conditions.},
}
@article {pmid31281920,
year = {2019},
author = {de Oliveira, ISR and Jesus, EDC and Ribeiro, TG and Santos Reis de Andrade da Silva, M and Tenorio, JO and Martins, LMV and de Faria, SM},
title = {Mimosa caesalpiniifolia Benth. adapts to rhizobia populations with differential taxonomy and symbiotic effectiveness outside of its location of origin.},
journal = {FEMS microbiology ecology},
volume = {95},
number = {8},
pages = {},
doi = {10.1093/femsec/fiz109},
pmid = {31281920},
issn = {1574-6941},
abstract = {Mimosa caesalpiniifolia Benth. is a legume native to the semi-arid region of Brazil, in the Northeast. Its successful adaptation to other locations, such as the Atlantic Forest in the Southeast region, may be related to its ability to establish symbiosis with nitrogen-fixing bacteria, especially β-rhizobia of the genus Paraburkholderia. The objective of this work was to determine whether M. caesalpiniifolia adapted to bacterial symbionts in locals where it was introduced. Bacteria were recovered from nodules of M. caesalpiniifolia and characterized at the genetic level by BOX-PCR and sequencing of the 16S rRNA, recA, nifH, and nodC genes. Their symbiotic effectiveness was assessed under axenic conditions. M. caesalpiniifolia nodulated mainly with Paraburkholderia sabiae and a few strains of Rhizobium in the Southeast. On the other hand, the symbionts found in the Northeast were, predominantly, Paraburkholderia diazotrophica. Regardless of its origin, P. diazotrophica promoted a superior accumulation of plant biomass than other bacterial species. The results presented here demonstrate the ability of M. caesalpiniifolia to adapt to bacterial populations outside its location of origin, and indicate that, in this case, the symbiotic effectiveness was associated with the taxonomical classification of the strains.},
}
@article {pmid31279967,
year = {2019},
author = {Wang, Y and White, MM and Moncalvo, JM},
title = {Diversification of the gut fungi Smittium and allies (Harpellales) co-occurred with the origin of complete metamorphosis of their symbiotic insect hosts (lower Diptera).},
journal = {Molecular phylogenetics and evolution},
volume = {139},
number = {},
pages = {106550},
doi = {10.1016/j.ympev.2019.106550},
pmid = {31279967},
issn = {1095-9513},
abstract = {Smittium (Harpellales, Kickxellomycotina) includes fungal symbionts associated with the digestive tracts of immature aquatic stages of various Diptera, including Chironomidae, Culicidae, Dixidae, Simuliidae, Thaumaleidae, and Tipulidae. With 84 species and the largest collection of cultured strains, Smittium has served as a model to understand the biology of these enigmatic trichomycetes gut fungi, from aspects of biodiversity, evolution, genomics, immunology, and physiology. However, evolutionary histories between Smittium species and their hosts are still not firmly established. Robust phylogenies of both Smittium sensu lato (s.l.) and their lower Diptera hosts have been reconstructed separately, facilitating comparative evolutionary studies between the two. The divergence time of the Smittium s.l. clade was estimated for the first time and compared with the evolutionary history of the insect hosts. The insect gut fungi diversified around 272 Ma (204-342 Ma), which co-occurred with the origin of complete metamorphosis of the insect hosts, presumably between 280 Ma and 355 Ma (~270 Ma for Diptera). A co-phylogenetic pattern was recovered for the insects and their symbiotic gut fungi using the statistical method ParaFit. Ancestral state reconstructions of the symbiotic relationship suggest that the ancestor of the Chironomidae may have contributed to the initiation of these insect-fungus symbiotic interactions. Further sampling and sequencing of Smittium and allies as well as their hosts are needed to uncover more patterns and interactions that may occur in this type of symbiosis.},
}
@article {pmid31277471,
year = {2019},
author = {Fukudome, M and Watanabe, E and Osuki, KI and Uchi, N and Uchiumi, T},
title = {Ectopic or Over-Expression of Class 1 Phytoglobin Genes Confers Flooding Tolerance to the Root Nodules of Lotus japonicus by Scavenging Nitric Oxide.},
journal = {Antioxidants (Basel, Switzerland)},
volume = {8},
number = {7},
pages = {},
doi = {10.3390/antiox8070206},
pmid = {31277471},
issn = {2076-3921},
support = {16-305, 17-309, and 18-312//National Institute of Basic Biology (NIBB)/ ; JP18J11872//JSPS KAKENHI Research Fellowship/ ; },
abstract = {Flooding limits biomass production in agriculture. Leguminous plants, important agricultural crops, use atmospheric dinitrogen gas as nitrogen nutrition by symbiotic nitrogen fixation with rhizobia, but this root-nodule symbiosis is sometimes broken down by flooding of the root system. In this study, we analyzed the effect of flooding on the symbiotic system of transgenic Lotus japonicus lines which overexpressed class 1 phytoglobin (Glb1) of L. japonicus (LjGlb1-1) or ectopically expressed that of Alnus firma (AfGlb1). In the roots of wild-type plants, flooding increased nitric oxide (NO) level and expression of senescence-related genes and decreased nitrogenase activity; in the roots of transgenic lines, these effects were absent or less pronounced. The decrease of chlorophyll content in leaves and the increase of reactive oxygen species (ROS) in roots and leaves caused by flooding were also suppressed in these lines. These results suggest that increased levels of Glb1 help maintain nodule symbiosis under flooding by scavenging NO and controlling ROS.},
}
@article {pmid31276218,
year = {2019},
author = {Burghardt, LT},
title = {Evolving together, evolving apart: measuring the fitness of rhizobial bacteria in and out of symbiosis with leguminous plants.},
journal = {The New phytologist},
volume = {},
number = {},
pages = {},
doi = {10.1111/nph.16045},
pmid = {31276218},
issn = {1469-8137},
support = {IOS-1237993//Division of Integrative Organismal Systems/ ; IOS-1724993//Division of Integrative Organismal Systems/ ; //National Science Foundation/ ; },
abstract = {Most plant-microbe interactions are facultative, with microbes experiencing temporally and spatially variable selection. How this variation affects microbial evolution is poorly understood. Given its tractability and ecological and agricultural importance, the legume-rhizobia nitrogen-fixing symbiosis is a powerful model for identifying traits and genes underlying bacterial fitness. New technologies allow high-throughput measurement of the relative fitness of bacterial mutants, strains and species in mixed inocula in the host, rhizosphere and soil environments. I consider how host genetic variation (G × G), other environmental factors (G × E), and host life-cycle variation may contribute to the maintenance of genetic variation and adaptive trajectories of rhizobia - and, potentially, other facultative symbionts. Lastly, I place these findings in the context of developing beneficial inoculants in a changing climate.},
}
@article {pmid31275282,
year = {2019},
author = {He, C and Wang, W and Hou, J},
title = {Characterization of Dark Septate Endophytic Fungi and Improve the Performance of Liquorice Under Organic Residue Treatment.},
journal = {Frontiers in microbiology},
volume = {10},
number = {},
pages = {1364},
doi = {10.3389/fmicb.2019.01364},
pmid = {31275282},
issn = {1664-302X},
abstract = {Dark septate endophytic (DSE) fungi is a diverse group of Ascomycetes fungi that colonize the plants roots, and may facilitate plant growth and fitness, however, their ecological roles need further clarification. This study aimed to evaluate the growth promoting effects of DSE fungi in a medicinal plant, liquorice (Glycyrrhiza uralensis), under additional organic residues. First, we isolated, identified and characterized, two DSE fungal species (Acrocalymma vagum and Paraboeremia putaminum) harboring inside the roots of liquorice growing in arid areas of China. Second, we examined the performance and rhizosphere soil parameters of liquorice plants inoculated with these fungi under additional sterilized organic residues and unsterilized organic residue (containing Trichoderma viride population) in a growth chamber. The results showed that two DSE strains could effectively colonize plant roots and formed a strain-dependent symbiosis with liquorice. DSE inoculation alone increased the plant biomass, and glycyrrhizic acid and glycyrrhizin content. It also improved the root system and N and P absorption by plants, consequently depleting these macronutrients in the soil. Residues alone increased soil organic matter, available phosphorus (P), and available nitrogen (N) content, and plant biomass, N, P, glycyrrhizic acid, and glycyrrhizin content. Mantel test and structural equation model (SEM) analysis demonstrated that DSE associated with residues significantly positively influenced soil organic matter, available P and available N, and plant biomass, glycyrrhizin, N, P, and root surface area. Variation in plant growth and glycyrrhizic acid and glycyrrhizin accumulation can be attributed to the effects of DSE inoculation. DSE associated with residues exhibited a general synergistic effect on the growth and accumulation of glycyrrhizic acid and glycyrrhizin of liquorice. We demonstrate for the first time, two DSE fungi in the liquorice roots that have potential use as promoter for the cultivation of medicinal plant.},
}
@article {pmid31275256,
year = {2019},
author = {Chen, B and Yu, K and Liang, J and Huang, W and Wang, G and Su, H and Qin, Z and Huang, X and Pan, Z and Luo, W and Luo, Y and Wang, Y},
title = {Latitudinal Variation in the Molecular Diversity and Community Composition of Symbiodiniaceae in Coral From the South China Sea.},
journal = {Frontiers in microbiology},
volume = {10},
number = {},
pages = {1278},
doi = {10.3389/fmicb.2019.01278},
pmid = {31275256},
issn = {1664-302X},
abstract = {Coral reefs are continuing to decline worldwide due to anthropogenic climate change. The study of the molecular diversity and biogeographical patterns of Symbiodiniaceae, is essential to understand the adaptive potential and resilience of coral-algal symbiosis. Next generation sequencing was used to analyze the Symbiodiniaceae rDNA internal transcribed spacer 2 marker genes from 178 reef-building coral samples in eight coral habitats across approximately 13° of latitude in the South China Sea (SCS). A total of three Symbiodiniaceae genera, Cladocopium, Durusdinium, and Gerakladium, as well as 31 dominant Symbiodiniaceae types, were identified. Symbiodiniaceae richness, diversity, and community composition varied according to latitude; intermediate and low latitude coral reefs (IR and LR) have higher Symbiodiniaceae richness and diversity than high latitude coral habitats (HC and HR). A PERMANOVA analysis found significant differences in the Symbiodiniaceae community composition in the SCS (F = 14.75, R2 = 0.20, p = 0.001 < 0.01). The major dominant Symbiodiniaceae types were C1 in the HC and the HR, C1/Cspc/C50/C15 and D1 in the IR, and C3u and C15 in the LR. Canonical correspondence analysis showed that the relative abundance of different Symbiodiniaceae types is affected by multiple environmental factors. Phylogenetic analysis indicated that the Symbiodiniaceae type Cladocopium, which shared common ancestors, shows similar environmental adaptability. Based on these results, we suggest that coral host species played a relatively small role in the identity of the dominant Symbiodiniaceae type. Therefore, the biogeographical patterns of Symbiodiniaceae may be mainly affected by environmental factors. Our research provides a comprehensive overview of the biogeography of Symbiodiniaceae in the SCS, where coral communities and reefs are widely distributed across different latitude regions and have variable environmental conditions. Our data will provide support for further study of the regional diversification of Symbiodiniaceae and the ecological resilience of the coral-Symbiodiniaceae symbioses.},
}
@article {pmid31274160,
year = {2019},
author = {Wang, X and Huo, H and Luo, Y and Liu, D and Zhao, L and Zong, L and Chou, M and Chen, J and Wei, G},
title = {Type III secretion systems impact Mesorhizobium amorphae CCNWGS0123 compatibility with Robinia pseudoacacia.},
journal = {Tree physiology},
volume = {},
number = {},
pages = {},
doi = {10.1093/treephys/tpz077},
pmid = {31274160},
issn = {1758-4469},
abstract = {Rhizobia and legume plants are famous mutualistic symbiosis partners who provide nitrogen nutrition to natural environment. Rhizobial type III secretion systems (T3SSs) deliver effectors that manipulate the metabolism of eukaryotic host cells. Mesorhizobium amorphae CCNWGS0123 (GS0123) contains two T3SS gene clusters, T3SS-I and T3SS-II. T3SS-I contains all the basal components for an integrated T3SS, and the expression of T3SS-I genes is up-regulated in the presence of flavonoids. In contrast, T3SS-II lacks the primary extracellular elements of T3SSs, and the expression of T3SS-II genes is down-regulated in the presence of flavonoids. Inoculation tests on Robinia pseudoacacia displayed considerable differences in gene expression patterns and levels among roots inoculated with GS0123 and T3SS-deficient mutant (GS0123ΔT1, GS0123ΔT2 or GS0123ΔS). Compared with the GS0123-inoculated plants, GS0123ΔT1-inoculated roots formed very few infection threads and effective nodules, while GS0123ΔT2-inoculated roots formed a little fewer infection threads and effective nodules with increased numbers of bacteroids enclosed in one symbiosome. Moreover, almost no infection threads or effective nodules were observed in GS0123ΔS-inoculated roots. In addition to evaluations of plant immunity signals, we observed that the coexistence of T3SS-I and T3SS-II promoted infection by suppressing host defense response in ROS defense response pathway. Future studies should focus on identifying rhizobial T3SS effectors and their host target proteins.},
}
@article {pmid31273746,
year = {2019},
author = {Vadakke-Madathil, S and Limaye, LS and Kale, VP and Chaudhry, HW},
title = {Flow Cytometry and Cell Sorting Using Hematopoietic Progenitor Cells.},
journal = {Methods in molecular biology (Clifton, N.J.)},
volume = {2029},
number = {},
pages = {235-246},
doi = {10.1007/978-1-4939-9631-5_18},
pmid = {31273746},
issn = {1940-6029},
abstract = {Flow cytometry is a widely used laser-based technology for rapid analysis of the expression of cell surface antigens and intracellular molecules in various cell types including hematopoietic stem/progenitor cells (HSPCs). Multiparametric analysis of individual cells within a short time frame makes this tool attractive and indispensable in the field of stem cell research. This is accomplished by harnessing the specific light scattering ability of the cell type, which determines its size and internal complexity. In addition, use of fluorescently conjugated antibodies allows the detection of a specific surface or intracellular antigen present at that particular stage. Fluorescent Activated Cell Sorting (FACS) is used to separate a subset of cells from a heterogeneous cell population based on fluorescent labeling. Here we describe the general principles of flow cytometry and detailed methods for the isolation of HSPCs using flow cytometry as a tool.},
}
@article {pmid31272899,
year = {2019},
author = {Plassard, C and Becquer, A and Garcia, K},
title = {Phosphorus Transport in Mycorrhiza: How Far Are We?.},
journal = {Trends in plant science},
volume = {24},
number = {9},
pages = {794-801},
doi = {10.1016/j.tplants.2019.06.004},
pmid = {31272899},
issn = {1878-4372},
abstract = {Mycorrhizal fungi considerably improve plant nutrition and help them to cope with changing environments. Particularly, these fungi express proteins to transfer inorganic phosphate (Pi) from the soil to colonized roots through symbiotic interfaces. The mechanisms involved in Pi transfer from fungal to plant cells are still largely unknown. Here, we discuss the recent progress made on the description of these mechanisms and we propose the most promising hypotheses and alternative mechanisms for this process. Specifically, we present a phylogenetic survey of candidate Pi transporters of mycorrhizal fungi that might ensure Pi unload into the symbiotic interfaces. Gathering additional knowledge on mycorrhizal Pi transport will improve the Pi-useefficiency in agroecological systems and will guide towards addressing future research challenges.},
}
@article {pmid31271695,
year = {2019},
author = {Harman, GE and Doni, F and Khadka, RB and Uphoff, N},
title = {Endophytic strains of Trichoderma increase plants' photosynthetic capability.},
journal = {Journal of applied microbiology},
volume = {},
number = {},
pages = {},
doi = {10.1111/jam.14368},
pmid = {31271695},
issn = {1365-2672},
abstract = {The world faces two enormous challenges that can be met, at least in part and at low cost, by making certain changes in agricultural practices. There is need to produce enough food and fibre for a growing population in the face of adverse climatic trends, and to remove greenhouse gases to avert the worst consequences of global climate change. Improving photosynthetic efficiency of crop plants can help meet both challenges. Fortuitously, when crop plants' roots are colonized by certain root endophytic fungi in the genus Trichoderma, this induces up-regulation of genes and pigments that improve the plants' photosynthesis. Plants under physiological or environmental stress suffer losses in their photosynthetic capability through damage to photosystems and other cellular processes caused by reactive oxygen species (ROS). But certain Trichoderma strains activate biochemical pathways that reduce ROS to less harmful molecules. This and other mechanisms described here make plants more resistant to biotic and abiotic stresses. The net effect of these fungi's residence in plants is to induce greater shoot and root growth, increasing crop yields, which will raise future food production. Furthermore, if photosynthesis rates are increased, more CO2 will be extracted from the atmosphere, and enhanced plant root growth means that more sequestered C will be transferred to roots and stored in the soil. Reductions in global greenhouse gas levels can be accelerated by giving incentives for climate-friendly carbon farming and carbon cap-and-trade programmes that reward practices transferring carbon from the atmosphere into the soil, also enhancing soil fertility and agricultural production.},
}
@article {pmid31271473,
year = {2019},
author = {Leeks, A and Dos Santos, M and West, SA},
title = {Transmission, relatedness, and the evolution of cooperative symbionts.},
journal = {Journal of evolutionary biology},
volume = {},
number = {},
pages = {},
doi = {10.1111/jeb.13505},
pmid = {31271473},
issn = {1420-9101},
support = {P2LAP3-158669//Schweizerischer Nationalfonds zur Förderung der Wissenschaftlichen Forschung/ ; BB/M011224/1//Biotechnology and Biological Sciences Research Council/United Kingdom ; },
abstract = {Cooperative interactions between species, termed mutualisms, play a key role in shaping natural ecosystems, economically important agricultural systems, and in influencing human health. Across different mutualisms, there is significant variation in the benefit that hosts receive from their symbionts. Empirical data suggest that transmission mode can help explain this variation: vertical transmission, where symbionts infect their host's offspring, leads to symbionts that provide greater benefits to their hosts than horizontal transmission, where symbionts leave their host and infect other hosts in the population. However, two different theoretical explanations have been given for this pattern: firstly, vertical transmission aligns the fitness interests of hosts and their symbionts; secondly, vertical transmission leads to increased relatedness between symbionts sharing a host, favouring cooperation between symbionts. We used a combination of analytical models and dynamic simulations to tease these factors apart, in order to compare their separate influences and see how they interact. We found that relatedness between symbionts sharing a host, rather than transmission mode per se, was the most important factor driving symbiont cooperation. Transmission mode mattered mainly because it determined relatedness. We also found evolutionary branching throughout much of our simulation, suggesting that a combination of transmission mode and multiplicity of infections could lead to the stable coexistence of different symbiont strategies.},
}
@article {pmid31271421,
year = {2019},
author = {Sørensen, MES and Lowe, CD and Minter, EJA and Wood, AJ and Cameron, DD and Brockhurst, MA},
title = {The role of exploitation in the establishment of mutualistic microbial symbioses.},
journal = {FEMS microbiology letters},
volume = {366},
number = {12},
pages = {},
doi = {10.1093/femsle/fnz148},
pmid = {31271421},
issn = {1574-6968},
abstract = {Evolutionary theory suggests that the conditions required for the establishment of mutualistic symbioses through mutualism alone are highly restrictive, often requiring the evolution of complex stabilising mechanisms. Exploitation, whereby initially the host benefits at the expense of its symbiotic partner and mutual benefits evolve subsequently through trade-offs, offers an arguably simpler route to the establishment of mutualistic symbiosis. In this review, we discuss the theoretical and experimental evidence supporting a role for host exploitation in the establishment and evolution of mutualistic microbial symbioses, including data from both extant and experimentally evolved symbioses. We conclude that exploitation rather than mutualism may often explain the origin of mutualistic microbial symbioses.},
}
@article {pmid31271364,
year = {2019},
author = {Kavadi, S},
title = {John B Grant and public health in India.},
journal = {Indian journal of medical ethics},
volume = {4},
number = {2},
pages = {123-128},
doi = {10.20529/IJME.2019.010},
pmid = {31271364},
issn = {0975-5691},
abstract = {From 1939 to 1945, John Black Grant a Rockefeller Foundation officer and former Professor of Public Health at the Peking Union Medical College served as the Director of the All Institute of Hygiene and Public Health, Calcutta. Grant's India tenure is important for his efforts to ameliorate the condition of public health in India. Much has been written about Grant's contribution to transforming public health in China but his work in India has not received sufficient attention. This article acquaints readers with some of his more noteworthy ideas and endeavours to remodel the colonial public health and medical system. His views on Indian public health may also be viewed as a critique of the colonial health system.},
}
@article {pmid31269590,
year = {2019},
author = {Wen, ZL and Chen, DC},
title = {[Clinical significance of intestinal micro-ecological symbiosis disruption in critically ill patients].},
journal = {Zhonghua yi xue za zhi},
volume = {99},
number = {25},
pages = {1921-1924},
doi = {10.3760/cma.j.issn.0376-2491.2019.25.001},
pmid = {31269590},
issn = {0376-2491},
mesh = {*Critical Illness ; Humans ; Intestines ; *Symbiosis ; },
}
@article {pmid31268231,
year = {2019},
author = {Xu, XR and Li, NN and Bao, XY and Douglas, AE and Luan, JB},
title = {Patterns of host cell inheritance in the bacterial symbiosis of whiteflies.},
journal = {Insect science},
volume = {},
number = {},
pages = {},
doi = {10.1111/1744-7917.12708},
pmid = {31268231},
issn = {1744-7917},
support = {31871967//National Natural Science Foundation of China/ ; 2018B0078//Liaoning and Shenyang High-Level Talent Support Foundation/ ; RC18001//Liaoning and Shenyang High-Level Talent Support Foundation/ ; OPP1058938//The Bill &amp; Melinda Gates foundation/ ; },
abstract = {Whiteflies possess bacterial symbionts Candidatus Portiera aleyrodidium that are housed in specialized cells called bacteriocytes and are faithfully transmitted via the ovary to insect offspring. In one whitefly species studied previously, Bemisia tabaci MEAM1, transmission is mediated by somatic inheritance of bacteriocytes, with a single bacteriocyte transferred to each oocyte and persisting through embryogenesis to the next generation. Here, we investigate the mode of bacteriocyte transmission in two whitefly species, B. tabaci MED, the sister species of MEAM1, and the phylogenetically distant species Trialeurodes vaporariorum. Microsatellite analysis supported by microscopical studies demonstrates that B. tabaci MED bacteriocytes are genetically different from other somatic cells and persist through embryogenesis, as for MEAM1, but T. vaporariorum bacteriocytes are genetically identical to other somatic cells of the insect, likely mediated by the degradation of maternal bacteriocytes in the embryo. These two alternative modes of transmission provide a first demonstration among insect symbioses that the cellular processes underlying vertical transmission of bacterial symbionts can diversify among related host species associated with a single lineage of symbiotic bacteria.},
}
@article {pmid31268133,
year = {2019},
author = {Elkrief, A and Derosa, L and Kroemer, G and Zitvogel, L and Routy, B},
title = {The negative impact of antibiotics on outcomes in cancer patients treated with immunotherapy: a new independent prognostic factor?.},
journal = {Annals of oncology : official journal of the European Society for Medical Oncology},
volume = {},
number = {},
pages = {},
doi = {10.1093/annonc/mdz206},
pmid = {31268133},
issn = {1569-8041},
abstract = {Immune checkpoint inhibitors (ICI) now represent the standard of care for several cancer types. In pre-clinical models, absence of an intact gut microbiome negatively impacted ICI efficacy and these findings permitted to unravel the importance of the commensal microbiota in immuno-oncology. Recently, multiple clinical studies including more than 1800 patients in aggregate demonstrated the negative predictive impact of treatments with broad-spectrum antibiotics (ATB) on cancer patients receiving ICI. Altogether, these results have led to the hypothesis that ATB-induced symbiosis might influence the clinical response through the modulation of the gut microbiome. Controversy still remains, as ATB treatment might simply constitute a surrogate marker of unfit or immunodeficient patients. In this review, we summarize recent publications addressing the impact of the gut microbiome on ICI efficacy, discuss currently available data on the effect of ATB administered in different time-frames respect to ICI initiation, and finally evoke the therapeutic implications of these findings.},
}
@article {pmid31267680,
year = {2019},
author = {Taubert, M and Grob, C and Crombie, A and Howat, AM and Burns, OJ and Weber, M and Lott, C and Kaster, AK and Vollmers, J and Jehmlich, N and von Bergen, M and Chen, Y and Murrell, JC},
title = {Communal metabolism by Methylococcaceae and Methylophilaceae is driving rapid aerobic methane oxidation in sediments of a shallow seep near Elba, Italy.},
journal = {Environmental microbiology},
volume = {},
number = {},
pages = {},
doi = {10.1111/1462-2920.14728},
pmid = {31267680},
issn = {1462-2920},
support = {GBMF3303//Gordon and Betty Moore Foundation/ ; ECF2016-626//Leverhulme Trust/ ; },
abstract = {The release of abiotic methane from marine seeps into the atmosphere is a major source of this potent greenhouse gas. Methanotrophic microorganisms in methane seeps use methane as carbon and energy source, thus significantly mitigating global methane emissions. Here, we investigated microbial methane oxidation at the sediment-water interface of a shallow marine methane seep. Metagenomics and metaproteomics, combined with 13 C-methane stable isotope probing, demonstrated that various members of the gammaproteobacterial family Methylococcaceae were the key players for methane oxidation, catalysing the first reaction step to methanol. We observed a transfer of carbon to methanol-oxidizing methylotrophs of the betaproteobacterial family Methylophilaceae, suggesting an interaction between methanotrophic and methylotrophic microorganisms that allowed for rapid methane oxidation. From our microcosms, we estimated methane oxidation rates of up to 871 nmol of methane per gram sediment per day. This implies that more than 50% of methane at the seep is removed by microbial oxidation at the sediment-water interface, based on previously reported in situ methane fluxes. The organic carbon produced was further assimilated by different heterotrophic microbes, demonstrating that the methane-oxidizing community supported a complex trophic network. Our results provide valuable eco-physiological insights into this specialized microbial community performing an ecosystem function of global relevance.},
}
@article {pmid31266522,
year = {2019},
author = {Cappelli, A and Valzano, M and Cecarini, V and Bozic, J and Rossi, P and Mensah, P and Amantini, C and Favia, G and Ricci, I},
title = {Killer yeasts exert anti-plasmodial activities against the malaria parasite Plasmodium berghei in the vector mosquito Anopheles stephensi and in mice.},
journal = {Parasites &amp; vectors},
volume = {12},
number = {1},
pages = {329},
doi = {10.1186/s13071-019-3587-4},
pmid = {31266522},
issn = {1756-3305},
support = {842429//European Research Council/International ; 842429//Horizon 2020- ERC POC 2018/ ; },
mesh = {Animals ; Anopheles/*microbiology/parasitology ; Antimalarials/*pharmacology ; Female ; Malaria/parasitology/*prevention &amp; control/transmission ; Mice ; Mosquito Vectors/*microbiology/parasitology ; Mycotoxins/*pharmacology ; Plasmodium berghei/*drug effects ; Saccharomycetales/*physiology ; Symbiosis ; },
abstract = {BACKGROUND: Wickerhamomyces anomalus is a yeast associated with different insects including mosquitoes, where it is proposed to be involved in symbiotic relationships with hosts. Different symbiotic strains of W. anomalus display a killer phenotype mediated by protein toxins with broad-spectrum antimicrobial activities. In particular, a killer toxin purified from a W. anomalus strain (WaF17.12), previously isolated from the malaria vector mosquito Anopheles stephensi, has shown strong in vitro anti-plasmodial activity against early sporogonic stages of the murine malaria parasite Plasmodium berghei.<br><br>RESULTS: Here, we provide evidence that WaF17.12 cultures, properly stimulated to induce the expression of the killer toxin, can directly affect in vitro P. berghei early sporogonic stages, causing membrane damage and parasite death. Moreover, we demonstrated by in vivo studies that mosquito dietary supplementation with activated WaF17.12 cells interfere with ookinete development in the midgut of An. stephensi. Besides the anti-sporogonic action of WaF17.12, an inhibitory effect of purified WaF17.12-killer toxin was observed on erythrocytic stages of P. berghei, with a consequent reduction of parasitaemia in mice. The preliminary safety tests on murine cell lines showed no side effects.<br><br>CONCLUSIONS: Our findings demonstrate the anti-plasmodial activity of WaF17.12 against different developmental stages of P. berghei. New studies on P. falciparum are needed to evaluate the use of killer yeasts as innovative tools in the symbiotic control of malaria.},
}
@article {pmid31262532,
year = {2019},
author = {Biedermann, PHW and Müller, J and Grégoire, JC and Gruppe, A and Hagge, J and Hammerbacher, A and Hofstetter, RW and Kandasamy, D and Kolarik, M and Kostovcik, M and Krokene, P and Sallé, A and Six, DL and Turrini, T and Vanderpool, D and Wingfield, MJ and Bässler, C},
title = {Bark Beetle Population Dynamics in the Anthropocene: Challenges and Solutions.},
journal = {Trends in ecology &amp; evolution},
volume = {},
number = {},
pages = {},
doi = {10.1016/j.tree.2019.06.002},
pmid = {31262532},
issn = {1872-8383},
abstract = {Tree-killing bark beetles are the most economically important insects in conifer forests worldwide. However, despite >200 years of research, the drivers of population eruptions and crashes are still not fully understood and the existing knowledge is thus insufficient to face the challenges posed by the Anthropocene. We critically analyze potential biotic and abiotic drivers of population dynamics of an exemplary species, the European spruce bark beetle (ESBB) (Ips typographus) and present a multivariate approach that integrates the many drivers governing this bark beetle system. We call for hypothesis-driven, large-scale collaborative research efforts to improve our understanding of the population dynamics of this and other bark beetle pests. Our approach can serve as a blueprint for tackling other eruptive forest insects.},
}
@article {pmid31262007,
year = {2019},
author = {Pilon-Smits, EAH},
title = {On the Ecology of Selenium Accumulation in Plants.},
journal = {Plants (Basel, Switzerland)},
volume = {8},
number = {7},
pages = {},
doi = {10.3390/plants8070197},
pmid = {31262007},
issn = {2223-7747},
abstract = {Plants accumulate and tolerate Se to varying degrees, up to 15,000 mg Se/kg dry weight for Se hyperaccumulators. Plant Se accumulation may exert positive or negative effects on other species in the community. The movement of plant Se into ecological partners may benefit them at low concentrations, but cause toxicity at high concentrations. Thus, Se accumulation can protect plants against Se-sensitive herbivores and pathogens (elemental defense) and reduce surrounding vegetation cover via high-Se litter deposition (elemental allelopathy). While hyperaccumulators negatively impact Se-sensitive ecological partners, they offer a niche for Se-tolerant partners, including beneficial microbial and pollinator symbionts as well as detrimental herbivores, pathogens, and competing plant species. These ecological effects of plant Se accumulation may facilitate the evolution of Se resistance in symbionts. Conversely, Se hyperaccumulation may evolve driven by increasing Se resistance in herbivores, pathogens, or plant neighbors; Se resistance also evolves in mutualist symbionts, minimizing the plant's ecological cost. Interesting topics to address in future research are whether the ecological impacts of plant Se accumulation may affect species composition across trophic levels (favoring Se resistant taxa), and to what extent Se hyperaccumulators form a portal for Se into the local food chain and are important for Se cycling in the local ecosystem.},
}
@article {pmid31261721,
year = {2019},
author = {Haro, R and Benito, B},
title = {The Role of Soil Fungi in K+ Plant Nutrition.},
journal = {International journal of molecular sciences},
volume = {20},
number = {13},
pages = {},
doi = {10.3390/ijms20133169},
pmid = {31261721},
issn = {1422-0067},
support = {AGL2016-80593-R//Ministerio de Economía, Industria y Competitividad, Gobierno de España/ ; },
abstract = {K+ is an essential cation and the most abundant in plant cells. After N, its corresponding element, K, is the nutrient required in the largest amounts by plants. Despite the numerous roles of K in crop production, improvements in the uptake and efficiency of use of K have not been major focuses in conventional or transgenic breeding studies in the past. In research on the mineral nutrition of plants in general, and K in particular, this nutrient has been shown to be essential to soil-dwelling-microorganisms (fungi, bacteria, protozoa, nematodes, etc.) that form mutualistic associations and that can influence the availability of mineral nutrients for plants. Therefore, this article aims to provide an overview of the role of soil microorganisms in supplying K+ to plants, considering both the potassium-solubilizing microorganisms and the potassium-facilitating microorganisms that are in close contact with the roots of plants. These microorganisms can influence the active transporter-mediated transfer of K+. Regarding the latter group of microorganisms, special focus is placed on the role of endophytic fungus. This review also includes a discussion on productivity through sustainable agriculture.},
}
@article {pmid31260142,
year = {2019},
author = {Pellegrin, C and Daguerre, Y and Ruytinx, J and Guinet, F and Kemppainen, M and Frey, NFD and Puech-Pagès, V and Hecker, A and Pardo, AG and Martin, FM and Veneault-Fourrey, C},
title = {Laccaria bicolor MiSSP8 is a small-secreted protein decisive for the establishment of the ectomycorrhizal symbiosis.},
journal = {Environmental microbiology},
volume = {},
number = {},
pages = {},
doi = {10.1111/1462-2920.14727},
pmid = {31260142},
issn = {1462-2920},
support = {//European Fund for Regional Development/ ; Plant-Microbe Interfaces Scientific Focus Area//Genomic Science Program, US Department of Energy, Office of Science, Biological and Environmental Research/ ; ANR-11-LABX-0002_ARBRE//Laboratory of Excellence ARBRE/ ; //Région Lorraine Research council/ ; },
abstract = {The ectomycorrhizal symbiosis is a predominant tree-microbe interaction in forest ecosystems sustaining tree growth and health. Its establishment and functioning implies a long-term and intimate relationship between the soil-borne fungi and the roots of trees. Mycorrhiza-induced Small-Secreted Proteins (MiSSPs) are hypothesized as keystone symbiotic proteins, required to set up the symbiosis by modifying the host metabolism and/or building the symbiotic interfaces. L. bicolor MiSSP8 is the third most highly induced MiSSPs in symbiotic tissues and it is also expressed in fruiting bodies. The MiSSP8-RNAi knockdown mutants are strongly impaired in their mycorrhization ability with Populus, with the lack of fungal mantle and Hartig net development due to the lack of hyphal aggregation. MiSSP8 C-terminus displays a repetitive motif containing a kexin cleavage site, recognized by KEX2 in vitro. This suggests MiSSP8 protein might be cleaved into small peptides. Moreover, the MiSSP8 repetitive motif is found in other proteins predicted secreted by both saprotrophic and ectomycorrhizal fungi. Thus, our data indicate that MiSSP8 is a small-secreted protein involved at early stages of ectomycorrhizal symbiosis, likely by regulating hyphal aggregation and pseudoparenchyma formation.},
}
@article {pmid31260050,
year = {2019},
author = {Carrier, TJ and Dupont, S and Reitzel, AM},
title = {Geographic location and food availability offer differing levels of influence on the bacterial communities associated with larval sea urchins.},
journal = {FEMS microbiology ecology},
volume = {95},
number = {8},
pages = {},
doi = {10.1093/femsec/fiz103},
pmid = {31260050},
issn = {1574-6941},
abstract = {Determining the factors underlying the assembly, structure, and diversity of symbiont communities remains a focal point of animal-microbiome research. Much of these efforts focus on taxonomic variation of microbiota within or between animal populations, but rarely test the proportional impacts of ecological components that may affect animal-associated microbiota. Using larvae from the sea urchin Strongylocentrotus droebachiensis from the Atlantic and Pacific Oceans, we test the hypothesis that, under natural conditions, inter-population differences in the composition of larval-associated bacterial communities are larger than intra-population variation due to a heterogeneous feeding environment. Despite significant differences in bacterial community structure within each S. droebachiensis larval population based on food availability, development, phenotype, and time, variation in OTU membership and community composition correlated more strongly with geographic location. Moreover, 20-30% of OTUs associated with larvae were specific to a single location while less than 10% were shared. Taken together, these results suggest that inter-populational variation in symbiont communities may be more pronounced than intra-populational variation, and that this difference may suggest that broad-scale ecological variables (e.g., across ocean basins) may mask smaller scale ecological variables (e.g., food availability).},
}
@article {pmid31257129,
year = {2019},
author = {Wein, T and Romero Picazo, D and Blow, F and Woehle, C and Jami, E and Reusch, TBH and Martin, WF and Dagan, T},
title = {Currency, Exchange, and Inheritance in the Evolution of Symbiosis.},
journal = {Trends in microbiology},
volume = {},
number = {},
pages = {},
doi = {10.1016/j.tim.2019.05.010},
pmid = {31257129},
issn = {1878-4380},
abstract = {Symbiotic interactions between eukaryotes and prokaryotes are widespread in nature. Here we offer a conceptual framework to study the evolutionary origins and ecological circumstances of species in beneficial symbiosis. We posit that mutual symbiotic interactions are well described by three elements: a currency, the mechanism of currency exchange, and mechanisms of symbiont inheritance. Each of these elements may be at the origin of symbiosis, with the other elements developing with time. The identity of currency in symbiosis depends on the ecological context of the symbiosis, while the specificity of the exchange mechanism underlies molecular adaptations for the symbiosis. The inheritance regime determines the degree of partner dependency and the symbiosis evolutionary trajectory. Focusing on these three elements, we review examples and open questions in the research on symbiosis.},
}
@article {pmid31254821,
year = {2019},
author = {Yang, XC and Han, ZZ and Ruan, XY and Chai, J and Jiang, SW and Zheng, R},
title = {Composting swine carcasses with nitrogen transformation microbial strains: Succession of microbial community and nitrogen functional genes.},
journal = {The Science of the total environment},
volume = {688},
number = {},
pages = {555-566},
doi = {10.1016/j.scitotenv.2019.06.283},
pmid = {31254821},
issn = {1879-1026},
abstract = {In this study, nitrogen transformation strains, including three ammonium transformation strains, one nitrite strain and one nitrogen fixer, were inoculated at different swine carcass composting stages to regulate the nitrogen transformation and control the nitrogen loss. The final total nitrogen content was significantly increased (p < 0.01). The bacterial communities were assessed by amplicon sequencing and association analysis. Proteobacteria, Actinobacteria, Bacteroidetes and Firmicutes were the four most dominant phyla.,Brevibacterium, Streptomyces and Ochrobactrum had a significant (p < 0.05) and positive correlation with total nitrogen and ammonium nitrogen content in both groups. The quantitative results of nitrogen transformation genes showed that ammonification, nitrification, denitrification and nitrogen fixation were simultaneously present in the composting process of swine carcasses, with the latter two accounting for a higher proportion. The ammonium transformation strains significantly (p < 0.05) strengthened nitrogen fixation and remarkably (p < 0.01) weakened nitrification and denitrification, which, however, were notably (p < 0.05) enhanced by the nitrite strain and nitrogen fixer. In this research, the inoculated strains changed the bacterial structure by regulating the abundance and activity of the highly connected taxa, which facilitated the growth of nitrogen transformation bacteria and regulated the balance/symbiosis of nitrogen transformation processes to accelerate the accumulation of nitrogen.},
}
@article {pmid31254637,
year = {2019},
author = {Bouletreau, P and Makaremi, M and Ibrahim, B and Louvrier, A and Sigaux, N},
title = {Artificial Intelligence: Applications in orthognathic surgery.},
journal = {Journal of stomatology, oral and maxillofacial surgery},
volume = {},
number = {},
pages = {},
doi = {10.1016/j.jormas.2019.06.001},
pmid = {31254637},
issn = {2468-7855},
abstract = {Artificial Intelligence (AI) applications have already invaded our everyday life, and the last 10 years have seen the emergence of very promising applications in the field of medicine. However, the literature dealing with the potential applications of IA in Orthognathic Surgery is remarkably poor to date. Yet, it is very likely that due to its amazing power in image recognition AI will find tremendous applications in dento-facial deformities recognition in a near future. In this article, we point out the state-of-the-art AI applications in medicine and its potential applications in the field of orthognathic surgery. AI is a very powerful tool and it is the responsibility of the entire medical profession to achieve a positive symbiosis between clinical sense and AI.},
}
@article {pmid31253759,
year = {2019},
author = {Liu, CW and Breakspear, A and Stacey, N and Findlay, K and Nakashima, J and Ramakrishnan, K and Liu, M and Xie, F and Endre, G and de Carvalho-Niebel, F and Oldroyd, GED and Udvardi, MK and Fournier, J and Murray, JD},
title = {A protein complex required for polar growth of rhizobial infection threads.},
journal = {Nature communications},
volume = {10},
number = {1},
pages = {2848},
doi = {10.1038/s41467-019-10029-y},
pmid = {31253759},
issn = {2041-1723},
support = {TULIP ANR-10-LABX-41 (TULIP)/COME-IN ANR-14-CE35-0007-01//Agence Nationale de la Recherche (French National Research Agency)/International ; BB/L010305/1//RCUK | Biotechnology and Biological Sciences Research Council (BBSRC)/International ; BB/L010305/1//RCUK | Biotechnology and Biological Sciences Research Council (BBSRC)/International ; },
mesh = {Agrobacterium ; Gene Expression Regulation, Plant ; Medicago truncatula/*genetics/*microbiology ; Plant Proteins/genetics/*metabolism ; Plant Root Nodulation/genetics/physiology ; Plant Roots ; Sinorhizobium meliloti/*physiology ; Symbiosis/physiology ; Two-Hybrid System Techniques ; },
abstract = {During root nodule symbiosis, intracellular accommodation of rhizobia by legumes is a prerequisite for nitrogen fixation. For many legumes, rhizobial colonization initiates in root hairs through transcellular infection threads. In Medicago truncatula, VAPYRIN (VPY) and a putative E3 ligase LUMPY INFECTIONS (LIN) are required for infection thread development but their cellular and molecular roles are obscure. Here we show that LIN and its homolog LIN-LIKE interact with VPY and VPY-LIKE in a subcellular complex localized to puncta both at the tip of the growing infection thread and at the nuclear periphery in root hairs and that the punctate accumulation of VPY is positively regulated by LIN. We also show that an otherwise nuclear and cytoplasmic exocyst subunit, EXO70H4, systematically co-localizes with VPY and LIN during rhizobial infection. Genetic analysis shows that defective rhizobial infection in exo70h4 is similar to that in vpy and lin. Our results indicate that VPY, LIN and EXO70H4 are part of the symbiosis-specific machinery required for polar growth of infection threads.},
}
@article {pmid31251718,
year = {2019},
author = {Bromfield, ESP and Cloutier, S and Nguyen, HDT},
title = {Description and complete genome sequence of Bradyrhizobium amphicarpaeae sp. nov., harbouring photosystem and nitrogen-fixation genes.},
journal = {International journal of systematic and evolutionary microbiology},
volume = {69},
number = {9},
pages = {2841-2848},
doi = {10.1099/ijsem.0.003569},
pmid = {31251718},
issn = {1466-5034},
abstract = {A bacterial strain, designated 39S1MBT, isolated from a root nodule of a soybean plant that had been inoculated with root-zone soil of Amphicarpaea bracteata (hog peanut) growing in Canada, was previously characterized and placed in a novel lineage within the genus Bradyrhizobium. The taxonomic status of strain 39S1MBT was verified by genomic and phenotypic analyses. Phylogenetic analyses of individual and concatenated protein-encoding gene sequences (atpD, glnII, recA, gyrB and rpoB) placed 39S1MBT in a lineage distinct from named species. Data for sequence similarities of concatenated genes relative to type strains of named species supported the phylogenetic data. Average nucleotide identity values of genome sequences (84.5-91.7 %) were well below the threshold value for bacterial species circumscription. Based on these data, Bradyrhizobium ottawaense OO99T and Bradyrhizobium shewense ERR11T are close relatives of 39S1MBT. The complete genome of 39S1MBT consists of a single 7.04 Mbp chromosome without a symbiosis island; G+C content is 64.7 mol%. Present in the genome are key photosystem and nitrogen-fixation genes, but not nodulation and type III secretion system genes. Sequence analysis of the nitrogen fixation gene, nifH, placed 39S1MBT in a novel lineage distinct from named Bradyrhizobium species. Data for phenotypic tests including growth characteristics and carbon source utilization supported the sequence-based analyses. Based on the data presented here, a novel species with the name Bradyrhizobium amphicarpaeae sp. nov. is proposed with 39S1MBT (=LMG 29934T=HAMBI 3680T) as the type strain.},
}
@article {pmid31249389,
year = {2019},
author = {Meunier, V and Bonnet, S and Pernice, M and Benavides, M and Lorrain, A and Grosso, O and Lambert, C and Houlbrèque, F},
title = {Bleaching forces coral's heterotrophy on diazotrophs and Synechococcus.},
journal = {The ISME journal},
volume = {},
number = {},
pages = {},
doi = {10.1038/s41396-019-0456-2},
pmid = {31249389},
issn = {1751-7370},
abstract = {Coral reefs are threatened by global warming, which disrupts the symbiosis between corals and their photosynthetic symbionts (Symbiodiniaceae), leading to mass coral bleaching. Planktonic diazotrophs or dinitrogen (N2)-fixing prokaryotes are abundant in coral lagoon waters and could be an alternative nutrient source for corals. Here we incubated untreated and bleached coral colonies of Stylophora pistillata with a 15N2-pre-labelled natural plankton assemblage containing diazotrophs. 15N2 assimilation rates in Symbiodiniaceae cells and tissues of bleached corals were 5- and 30-fold higher, respectively, than those measured in untreated corals, demonstrating that corals incorporate more nitrogen derived from planktonic diazotrophs under bleaching conditions. Bleached corals also preferentially fed on Synechococcus, nitrogen-rich picophytoplanktonic cells, instead of Prochlorococcus and picoeukaryotes, which have a lower cellular nitrogen content. By providing an alternative source of bioavailable nitrogen, both the incorporation of nitrogen derived from planktonic diazotrophs and the ingestion of Synechococcus may have profound consequences for coral bleaching recovery, especially for the many coral reef ecosystems characterized by high abundance and activity of planktonic diazotrophs.},
}
@article {pmid31245768,
year = {2019},
author = {Kramer, EM and Statter, SA and Yi, HJ and Carlson, JW and McClelland, DHR},
title = {Flowering plant immune repertoires expand under mycorrhizal symbiosis.},
journal = {Plant direct},
volume = {3},
number = {3},
pages = {e00125},
doi = {10.1002/pld3.125},
pmid = {31245768},
issn = {2475-4455},
abstract = {Immune perception in flowering plants is mediated by a repertoire of cytoplasmic and cell-surface receptors that detect invading microbes and their effects on cells. Here, we show that several large families of immune receptors exhibit size variations related to a plant's competence to host symbiotic root fungi (mycorrhiza). Plants that do not participate in mycorrhizal associations have significantly smaller immune repertoires, while the most promiscuous symbiotic hosts (ectomycorrhizal plant species) have significantly larger immune repertoires. By contrast, we find no significant increase in immune repertoire size among legumes competent to form a symbiosis with nitrogen-fixing bacteria (rhizobia). To explain these observations, we hypothesize that plant immune repertoire size expands with symbiote species diversity.},
}
@article {pmid31244787,
year = {2019},
author = {Heise, P and Liu, Y and Degenkolb, T and Vogel, H and Schäberle, TF and Vilcinskas, A},
title = {Antibiotic-Producing Beneficial Bacteria in the Gut of the Burying Beetle Nicrophorus vespilloides.},
journal = {Frontiers in microbiology},
volume = {10},
number = {},
pages = {1178},
doi = {10.3389/fmicb.2019.01178},
pmid = {31244787},
issn = {1664-302X},
abstract = {The increasing prevalence of antibiotic-resistant human pathogens is a growing public concern and there is intense pressure to identify new antibacterial compounds that can be developed into antibiotics with novel mode of action. Evolutionary theory predicts that insects that have evolved to occupy sophisticated ecological niches by feeding and reproducing on carcasses will depend on their gut microbiome to prevent colonization by invading pathogens taken up with the diet. This inspired our hypothesis that the complex interactions between the core microbiome and the more flexible microbial communities dependent on the environment may promote the outsourcing of antibiotic synthesis to beneficial microbes. We tested this hypothesis by cultivating and characterizing bacteria isolated from the gut of the burying beetle Nicrophorus vespilloides, which feeds and reproduces on small vertebrate carcasses buried in the soil to avoid competitors such as fly maggots. The extracts of isolated bacteria were screened for activity against human pathogens such as Escherichia coli, Pseudomonas aeruginosa, Staphylococcus aureus, and Candida albicans. More than 400 strains were isolated, among which the crude extract of Serratia marcescens 2MH3-2 displayed promising activity against Staphylococcus aureus. Bioactivity-guided fractionation enabled purification of the primary antimicrobial compound of the extract. By LC-MS and NMR experiments, it was identified as serrawettin W2 (C38H61N5O9), the antibacterial and nematostatic activity of which was corroborated in our study. We postulate that this antibiotic could contribute to the control of both bacteria and phoretic nematodes in the gut, which compete for food when transferred to the carcass. Our study shows that the gut microbiome of N. vespilloides is a promising resource for the screening of antibiotic-producing bacteria.},
}
@article {pmid31243442,
year = {2019},
author = {Vuong, HQ and McFrederick, QS},
title = {Comparative Genomics of Wild Bee and Flower Isolated Lactobacillus Reveals Potential Adaptation to the Bee Host.},
journal = {Genome biology and evolution},
volume = {11},
number = {8},
pages = {2151-2161},
doi = {10.1093/gbe/evz136},
pmid = {31243442},
issn = {1759-6653},
abstract = {Symbiosis with bacteria is common across insects, resulting in adaptive host phenotypes. The recently described bacterial symbionts Lactobacillus micheneri, Lactobacillus timberlakei, and Lactobacillus quenuiae are found in wild bee pollen provisions, bee guts, and flowers but have small genomes in comparison to other lactobacilli. We sequenced, assembled, and analyzed 27 new L. micheneri clade genomes to identify their possible ecological functions in flower and bee hosts. We determined possible key functions for the L. micheneri clade by identifying genes under positive selection, balancing selection, genes gained or lost, and population structure. A host adherence factor shows signatures of positive selection, whereas other orthologous copies are variable within the L. micheneri clade. The host adherence factors serve as strong evidence that these lactobacilli are adapted to animal hosts as their targets are found in the digestive tract of insects. Next, the L. micheneri clade is adapted toward a nutrient-rich environment, corroborating observations of where L. micheneri is most abundant. Additionally, genes involved in osmotolerance, pH tolerance, temperature resistance, detoxification, and oxidative stress response show signatures of selection that allow these bacteria to thrive in pollen and nectar masses in bee nests and in the bee gut. Altogether, these findings not only suggest that the L. micheneri clade is primarily adapted to the wild bee gut but also exhibit genomic features that would be beneficial to survival in flowers.},
}
@article {pmid31239506,
year = {2019},
author = {Van Treuren, W and Brower, KK and Labanieh, L and Hunt, D and Lensch, S and Cruz, B and Cartwright, HN and Tran, C and Fordyce, PM},
title = {Live imaging of Aiptasia larvae, a model system for coral and anemone bleaching, using a simple microfluidic device.},
journal = {Scientific reports},
volume = {9},
number = {1},
pages = {9275},
doi = {10.1038/s41598-019-45167-2},
pmid = {31239506},
issn = {2045-2322},
abstract = {Coral reefs, and their associated diverse ecosystems, are of enormous ecological importance. In recent years, coral health has been severely impacted by environmental stressors brought on by human activity and climate change, threatening the extinction of several major reef ecosystems. Reef damage is mediated by a process called 'coral bleaching' where corals, sea anemones, and other cnidarians lose their photosynthetic algal symbionts (family Symbiodiniaceae) upon stress induction, resulting in drastically decreased host energy harvest and, ultimately, coral death. The mechanism by which this critical cnidarian-algal symbiosis is lost remains poorly understood. The larvae of the sea anemone, Exaiptasia pallida (commonly referred to as 'Aiptasia') are an attractive model organism to study this process, but they are large (∼100 mm in length, ∼75 mm in diameter), deformable, and highly motile, complicating long-term imaging and limiting study of this critical endosymbiotic relationship in live organisms. Here, we report 'Traptasia', a simple microfluidic device with multiple traps designed to isolate and image individual, live larvae of Aiptasia and their algal symbionts over extended time courses. Using a trap design parameterized via fluid flow simulations and polymer bead loading tests, we trapped Aiptasia larvae containing algal symbionts and demonstrated stable imaging for >10 hours. We visualized algae within Aiptasia larvae and observed algal expulsion under an environmental stressor. To our knowledge, this device is the first to enable time-lapsed, high-throughput live imaging of cnidarian larvae and their algal symbionts and, in further implementation, could provide important insights into the cellular mechanisms of cnidarian bleaching under different environmental stressors. The 'Traptasia' device is simple to use, requires minimal external equipment and no specialized training to operate, and can easily be adapted using the trap optimization data presented here to study a variety of large, motile organisms.},
}
@article {pmid31239394,
year = {2019},
author = {Turon, M and Uriz, MJ and Martin, D},
title = {Multipartner Symbiosis across Biological Domains: Looking at the Eukaryotic Associations from a Microbial Perspective.},
journal = {mSystems},
volume = {4},
number = {4},
pages = {},
doi = {10.1128/mSystems.00148-19},
pmid = {31239394},
issn = {2379-5077},
abstract = {Sponges establish tight associations with both micro- and macroorganisms. However, while studies on sponge microbiomes are numerous, nothing is currently known about the microbiomes of sponge-associated polychaetes and their relationships with those of their host sponges. We analyzed the bacterial communities of symbiotic polychaetes (Haplosyllis spp.) and their host sponges (Clathria reinwardti, Amphimedon paraviridis, Neofibularia hartmani, and Aaptos suberitoides) to assess the influence of the sponges on the polychaete microbiomes. We identified both eukaryote partners by molecular (16S and COI genes) and morphological features, and we identified their microbial communities by high-throughput sequencing of the 16S rRNA gene (V4 region). We unravel the existence of six Haplosyllis species (five likely undescribed) associated at very high densities with the study sponge species in Nha Trang Bay (central Vietnam). A single polychaete species inhabited A. paraviridis and was different from the single species that inhabited A. suberitoides Conversely, two different polychaete species were found in C. reinwardti and N. hartmani, depending on the two host locations. Regardless of the host sponge, polychaete microbiomes were species specific, which is a widespread feature in marine invertebrates. More than half of the polychaete bacteria were also found in the host sponge microbiome but at contrasting abundances. Thus, the associated polychaetes seemed to be able to select, incorporate, and enrich part of the sponge microbiome, a selection that appears to be polychaete species specific. Moreover, the bacterial diversity is similar in both eukaryotic partners, which additionally confirms the influence of food (host sponge) on the structure of the polychaete microbiome.IMPORTANCE The symbiotic lifestyle represents a fundamental cryptic contribution to the diversity of marine ecosystems. Sponges are ideal targets to improve understanding the symbiotic relationships from evolutionary and ecological points of view, because they are the most ancient metazoans on earth, are ubiquitous in the marine benthos, and establish complex symbiosis with both prokaryotes and animals, which in turn also harbor their own bacterial communities. Here, we study the microbiomes of sponge-polychaete associations and confirm that polychaetes feed on their host sponges. The study worms select and enrich part of the sponge microbiome to shape their own species-specific bacterial communities. Moreover, worm microbiome diversity runs parallel to that of its food host sponge. Considering our results on symbiotic polychaetes and previous studies on fishes and mammals, diet appears to be an important source of bacteria for animals to shape their species-specific microbiomes.},
}
@article {pmid31239345,
year = {2019},
author = {Wong, JEMM and Nadzieja, M and Madsen, LH and Bücherl, CA and Dam, S and Sandal, NN and Couto, D and Derbyshire, P and Uldum-Berentsen, M and Schroeder, S and Schwämmle, V and Nogueira, FCS and Asmussen, MH and Thirup, S and Radutoiu, S and Blaise, M and Andersen, KR and Menke, FLH and Zipfel, C and Stougaard, J},
title = {A Lotus japonicus cytoplasmic kinase connects Nod factor perception by the NFR5 LysM receptor to nodulation.},
journal = {Proceedings of the National Academy of Sciences of the United States of America},
volume = {116},
number = {28},
pages = {14339-14348},
doi = {10.1073/pnas.1815425116},
pmid = {31239345},
issn = {1091-6490},
abstract = {The establishment of nitrogen-fixing root nodules in legume-rhizobia symbiosis requires an intricate communication between the host plant and its symbiont. We are, however, limited in our understanding of the symbiosis signaling process. In particular, how membrane-localized receptors of legumes activate signal transduction following perception of rhizobial signaling molecules has mostly remained elusive. To address this, we performed a coimmunoprecipitation-based proteomics screen to identify proteins associated with Nod factor receptor 5 (NFR5) in Lotus japonicus. Out of 51 NFR5-associated proteins, we focused on a receptor-like cytoplasmic kinase (RLCK), which we named NFR5-interacting cytoplasmic kinase 4 (NiCK4). NiCK4 associates with heterologously expressed NFR5 in Nicotiana benthamiana, and directly binds and phosphorylates the cytoplasmic domains of NFR5 and NFR1 in vitro. At the cellular level, Nick4 is coexpressed with Nfr5 in root hairs and nodule cells, and the NiCK4 protein relocates to the nucleus in an NFR5/NFR1-dependent manner upon Nod factor treatment. Phenotyping of retrotransposon insertion mutants revealed that NiCK4 promotes nodule organogenesis. Together, these results suggest that the identified RLCK, NiCK4, acts as a component of the Nod factor signaling pathway downstream of NFR5.},
}
@article {pmid31237779,
year = {2019},
author = {Oh, HYP and Visvalingam, V and Wahli, W},
title = {The PPAR-microbiota-metabolic organ trilogy to fine-tune physiology.},
journal = {FASEB journal : official publication of the Federation of American Societies for Experimental Biology},
volume = {33},
number = {9},
pages = {9706-9730},
doi = {10.1096/fj.201802681RR},
pmid = {31237779},
issn = {1530-6860},
abstract = {The human gut is colonized by commensal microorganisms, predominately bacteria that have coevolved in symbiosis with their host. The gut microbiota has been extensively studied in recent years, and many important findings on how it can regulate host metabolism have been unraveled. In healthy individuals, feeding timing and type of food can influence not only the composition but also the circadian oscillation of the gut microbiota. Host feeding habits thus influence the type of microbe-derived metabolites produced and their concentrations throughout the day. These microbe-derived metabolites influence many aspects of host physiology, including energy metabolism and circadian rhythm. Peroxisome proliferator-activated receptors (PPARs) are a group of ligand-activated transcription factors that regulate various metabolic processes such as fatty acid metabolism. Similar to the gut microbiota, PPAR expression in various organs oscillates diurnally, and studies have shown that the gut microbiota can influence PPAR activities in various metabolic organs. For example, short-chain fatty acids, the most abundant type of metabolites produced by anaerobic fermentation of dietary fibers by the gut microbiota, are PPAR agonists. In this review, we highlight how the gut microbiota can regulate PPARs in key metabolic organs, namely, in the intestines, liver, and muscle. Knowing that the gut microbiota impacts metabolism and is altered in individuals with metabolic diseases might allow treatment of these patients using noninvasive procedures such as gut microbiota manipulation.-Oh, H. Y. P., Visvalingam, V., Wahli, W. The PPAR-microbiota-metabolic organ trilogy to fine-tune physiology.},
}
@article {pmid31237728,
year = {2019},
author = {Nadal-Jimenez, P and Griffin, JS and Davies, L and Frost, CL and Marcello, M and Hurst, GDD},
title = {Genetic manipulation allows in vivo tracking of the life cycle of the son-killer symbiont, Arsenophonus nasoniae, and reveals patterns of host invasion, tropism and pathology.},
journal = {Environmental microbiology},
volume = {21},
number = {8},
pages = {3172-3182},
doi = {10.1111/1462-2920.14724},
pmid = {31237728},
issn = {1462-2920},
support = {708232//H2020 Marie Skłodowska-Curie Actions/ ; 704382//H2020 Marie Skłodowska-Curie Actions/ ; NE/I01067X/1//Natural Environment Research Council/ ; BB/L014947/1//Biotechnology and Biological Sciences Research Council/United Kingdom ; },
abstract = {Maternally heritable symbionts are common in arthropods and represent important partners and antagonists. A major impediment to understanding the mechanistic basis of these symbioses has been lack of genetic manipulation tools, for instance, those enabling transgenic GFP expression systems for in vivo visualization. Here, we transform the 'son-killer' reproductive parasite Arsenophonus nasoniae that infects the parasitic wasp Nasonia vitripennis with the plasmid pOM1-gfp, re-introduce this strain to N. vitripennis and then used this system to track symbiont life history in vivo. These data revealed transfer of the symbiont into the fly pupa by N. vitripennis during oviposition and N. vitripennis larvae developing infection over time through feeding. A strong tropism of A. nasoniae to the N. vitripennis ovipositor developed during wasp pupation, which aids onward transmission. The symbiont was also visualized in diapause larvae. Occasional necrotic diapause larvae were observed which displayed intense systemic infection alongside widespread melanotic nodules indicative of an active but failed immune response. Our results provide the foundation for the study of this symbiosis through in vivo tracking of the fate of symbionts through host development, which is rarely achieved in heritable microbe/insect interactions.},
}
@article {pmid31236967,
year = {2019},
author = {Chomicki, G and Renner, SS},
title = {Farming by ants remodels nutrient uptake in epiphytes.},
journal = {The New phytologist},
volume = {223},
number = {4},
pages = {2011-2023},
doi = {10.1111/nph.15855},
pmid = {31236967},
issn = {1469-8137},
support = {//Queen's College, University of Oxford/ ; RE 603/20-1//Deutsche Forschungsgemeinschaft/ ; RE 603/20-2//Deutsche Forschungsgemeinschaft/ ; //University of Oxford/ ; },
abstract = {True agriculture - defined by habitual planting, cultivation, harvesting and dependence of a farmer on a crop - is known from fungi farmed by ants, termites or beetles, and plants farmed by humans or ants. Because farmers supply their crops with nutrients, they have the potential to modify crop nutrition over evolutionary time. Here we test this hypothesis in ant/plant farming symbioses. We used field experiments, phylogenetic-comparative analyses and computed-tomography scanning to investigate how the evolution of farming by ants has impacted the nutrition of locally coexisting species in the epiphytic genus Squamellaria (Rubiaceae). Using isotope-labelled mineral and organic nitrogen, we show that specialised ants actively and exclusively fertilise hyperabsorptive warts on the inner walls of plant-formed structures (domatia) where they nest, sharply contrasting with nitrogen provisioning by ants in nonfarming generalist symbioses. Similar hyperabsorptive warts have evolved repeatedly in lineages colonised by farming ants. Our study supports the idea that millions of years of ant agriculture have remodelled plant physiology, shifting from ant-derived nutrients as by-products to active and targeted fertilisation on hyperabsorptive sites. The increased efficiency of ant-derived nutrient provisioning appears to stem from a combination of farming ant behaviour and plant 'crop' traits.},
}
@article {pmid31236871,
year = {2019},
author = {Rolim, L and Santiago, TR and Dos Reis Junior, FB and de Carvalho Mendes, I and do Vale, HMM and Hungria, M and Silva, LP},
title = {Identification of soybean Bradyrhizobium strains used in commercial inoculants in Brazil by MALDI-TOF mass spectrometry.},
journal = {Brazilian journal of microbiology : [publication of the Brazilian Society for Microbiology]},
volume = {},
number = {},
pages = {},
doi = {10.1007/s42770-019-00104-3},
pmid = {31236871},
issn = {1678-4405},
support = {465133/2014-4//Conselho Nacional de Desenvolvimento Científico e Tecnológico/ ; 02.13.08.001.00.00//Empresa Brasileira de Pesquisa Agropecuária/ ; },
abstract = {Biological nitrogen fixation (BNF) with the soybean crop probably represents the major sustainable technology worldwide, saving billions of dollars in N fertilizers and decreasing water pollution and the emission of greenhouse gases. Accordingly, the identification of strains occupying nodules under field conditions represents a critical step in studies that are aimed at guaranteeing increased BNF contribution. Current methods of identification are mostly based on serology, or on DNA profiles. However, the production of antibodies is restricted to few laboratories, and to obtain DNA profiles of hundreds of isolates is costly and time-consuming. Conversely, the matrix-assisted laser desorption/ionization time-of-flight (MALDI-TOF) MS technique might represent a golden opportunity for replacing serological and DNA-based methods. However, MALDI-TOF databases of environmental microorganisms are still limited, and, most importantly, there are concerns about the discrimination of protein profiles at the strain level. In this study, we investigated four soybean rhizobial strains carried in commercial inoculants used in over 35 million hectares in Brazil and also in other countries of South America and Africa. A supplementary MALDI-TOF database with the protein profiles of these rhizobial strains was built and allowed the identification of unique profiles statistically supported by multivariate analysis and neural networks. To test this new database, the nodule occupancy by Bradyrhizobium strains in symbiosis with soybean was characterized in a field experiment and the results were compared with serotyping of bacteria by immuno-agglutination. The results obtained by both techniques were highly correlated and confirmed the viability of using the MALDI-TOF MS technique to effectively distinguish bacteria at the strain level.},
}
@article {pmid31236592,
year = {2019},
author = {Kenny, NJ and Plese, B and Riesgo, A and Itskovich, VB},
title = {Symbiosis, Selection and Novelty: Freshwater Adaptation in the Unique Sponges of Lake Baikal.},
journal = {Molecular biology and evolution},
volume = {},
number = {},
pages = {},
doi = {10.1093/molbev/msz151},
pmid = {31236592},
issn = {1537-1719},
abstract = {Freshwater sponges (Spongillida) are a unique lineage of demosponges that secondarily colonized lakes and rivers and are now found ubiquitously in these ecosystems. They developed specific adaptations to freshwater systems, including the ability to survive extreme thermal ranges, long-lasting dessication, anoxia, and resistance to a variety of pollutants. While spongillids have colonized all freshwater systems, the family Lubomirskiidae is endemic to Lake Baikal, and plays a range of key roles in this ecosystem. Our work compares the genomic content and microbiome of individuals of three species of the Lubomirskiidae, providing hypotheses for how molecular evolution has allowed them to adapt to their unique environments. We have sequenced deep (>92% of the metazoan 'Benchmarking Universal Single-Copy Orthologs' (BUSCO) set) transcriptomes from three species of Lubomirskiidae and a draft genome resource for Lubomirskia baikalensis. We note Baikal sponges contain unicellular algal and bacterial symbionts, as well as the dinoflagellate Gyrodinium. We investigated molecular evolution, gene duplication and novelty in freshwater sponges compared to marine lineages. Sixty one orthogroups have consilient evidence of positive selection. Transporters (e.g. zinc transporter-2), transcription factors (aristaless-related homeobox) and structural proteins (for example actin-3), alongside other genes, are under strong evolutionary pressure in freshwater, with duplication driving novelty across the Spongillida, but especially in the Lubomirskiidae. This addition to knowledge of freshwater sponge genetics provides a range of tools for understanding the molecular biology and, in the future, the ecology (for example, colonization and migration patterns) of these key species.},
}
@article {pmid31235587,
year = {2019},
author = {Nakayama, T and Nomura, M and Takano, Y and Tanifuji, G and Shiba, K and Inaba, K and Inagaki, Y and Kawata, M},
title = {Single-cell genomics unveiled a cryptic cyanobacterial lineage with a worldwide distribution hidden by a dinoflagellate host.},
journal = {Proceedings of the National Academy of Sciences of the United States of America},
volume = {116},
number = {32},
pages = {15973-15978},
doi = {10.1073/pnas.1902538116},
pmid = {31235587},
issn = {1091-6490},
abstract = {Cyanobacteria are one of the most important contributors to oceanic primary production and survive in a wide range of marine habitats. Much effort has been made to understand their ecological features, diversity, and evolution, based mainly on data from free-living cyanobacterial species. In addition, symbiosis has emerged as an important lifestyle of oceanic microbes and increasing knowledge of cyanobacteria in symbiotic relationships with unicellular eukaryotes suggests their significance in understanding the global oceanic ecosystem. However, detailed characteristics of these cyanobacteria remain poorly described. To gain better insight into marine cyanobacteria in symbiosis, we sequenced the genome of cyanobacteria collected from a cell of a pelagic dinoflagellate that is known to host cyanobacterial symbionts within a specialized chamber. Phylogenetic analyses using the genome sequence revealed that the cyanobacterium represents an underdescribed lineage within an extensively studied, ecologically important group of marine cyanobacteria. Metagenomic analyses demonstrated that this cyanobacterial lineage is globally distributed and strictly coexists with its host dinoflagellates, suggesting that the intimate symbiotic association allowed the cyanobacteria to escape from previous metagenomic studies. Furthermore, a comparative analysis of the protein repertoire with related species indicated that the lineage has independently undergone reductive genome evolution to a similar extent as Prochlorococcus, which has the most reduced genomes among free-living cyanobacteria. Discovery of this cyanobacterial lineage, hidden by its symbiotic lifestyle, provides crucial insights into the diversity, ecology, and evolution of marine cyanobacteria and suggests the existence of other undiscovered cryptic cyanobacterial lineages.},
}
@article {pmid31234272,
year = {2019},
author = {Lan, Q and Liu, C and Ling, S},
title = {Research on Measurement of Symbiosis Degree Between National Fitness and the Sports Industry from the Perspective of Collaborative Development.},
journal = {International journal of environmental research and public health},
volume = {16},
number = {12},
pages = {},
doi = {10.3390/ijerph16122191},
pmid = {31234272},
issn = {1660-4601},
abstract = {Clarifying the symbiotic relationship between national fitness and the sports industry has important theoretical and practical significance for the collaborative development of the two. In order to measure and verify the symbiotic relationship between national fitness and the sports industry, we introduce a &quot;symbiosis degree&quot; model test method for the measurement of the symbiotic relationship during 2000-2017 between the two. Our results show that national fitness and the sports industry have symbiotic sufficient and necessary conditions, for both of which there is a symbiotic relationship, and a non-symmetric reciprocal symbiotic mode long-term. Overall, the impact of national fitness on the sports industry is greater than the impact of the sports industry on national fitness. From a structural perspective, there is a certain difference in the mutual influence of national fitness and the sports industry in the field of sports goods and sports services. In a dynamic forecast, we found that national fitness and the sports industry have the development trend of a symmetric reciprocal symbiotic state. Through theoretical studies, data measured and simulated projections, we believe that the symbiosis degree of the measurement model for the detection and prediction of the symbiotic unit of the symbiotic relationship between them to be of practical value.},
}
@article {pmid31233506,
year = {2019},
author = {Cui, G and Liew, YJ and Li, Y and Kharbatia, N and Zahran, NI and Emwas, AH and Eguiluz, VM and Aranda, M},
title = {Host-dependent nitrogen recycling as a mechanism of symbiont control in Aiptasia.},
journal = {PLoS genetics},
volume = {15},
number = {6},
pages = {e1008189},
doi = {10.1371/journal.pgen.1008189},
pmid = {31233506},
issn = {1553-7404},
abstract = {The metabolic symbiosis with photosynthetic algae allows corals to thrive in the oligotrophic environments of tropical seas. Different aspects of this relationship have been investigated using the emerging model organism Aiptasia. However, many fundamental questions, such as the nature of the symbiotic relationship and the interactions of nutrients between the partners remain highly debated. Using a meta-analysis approach, we identified a core set of 731 high-confidence symbiosis-associated genes that revealed host-dependent recycling of waste ammonium and amino acid synthesis as central processes in this relationship. Subsequent validation via metabolomic analyses confirmed that symbiont-derived carbon enables host recycling of ammonium into nonessential amino acids. We propose that this provides a regulatory mechanism to control symbiont growth through a carbon-dependent negative feedback of nitrogen availability to the symbiont. The dependence of this mechanism on symbiont-derived carbon highlights the susceptibility of this symbiosis to changes in carbon translocation, as imposed by environmental stress.},
}
@article {pmid31231402,
year = {2019},
author = {Bapaume, L and Laukamm, S and Darbon, G and Monney, C and Meyenhofer, F and Feddermann, N and Chen, M and Reinhardt, D},
title = {VAPYRIN Marks an Endosomal Trafficking Compartment Involved in Arbuscular Mycorrhizal Symbiosis.},
journal = {Frontiers in plant science},
volume = {10},
number = {},
pages = {666},
doi = {10.3389/fpls.2019.00666},
pmid = {31231402},
issn = {1664-462X},
abstract = {Arbuscular mycorrhiza (AM) is a symbiosis between plants and AM fungi that requires the intracellular accommodation of the fungal partner in the host. For reciprocal nutrient exchange, AM fungi form intracellular arbuscules that are surrounded by the peri-arbuscular membrane. This membrane, together with the fungal plasma membrane, and the space in between, constitute the symbiotic interface, over which nutrients are exchanged. Intracellular establishment of AM fungi requires the VAPYRIN protein which is induced in colonized cells, and which localizes to numerous small mobile structures of unknown identity (Vapyrin-bodies). In order to characterize the identity and function of the Vapyrin-bodies we pursued a dual strategy. First, we co-expressed fluorescently tagged VAPYRIN with a range of subcellular marker proteins, and secondly, we employed biochemical tools to identify interacting partner proteins of VAPYRIN. As an important tool for the quantitative analysis of confocal microscopic data sets from co-expression of fluorescent proteins, we developed a semi-automated image analysis pipeline that allows for precise spatio-temporal quantification of protein co-localization and of the dynamics of organelle association from movies. Taken together, these experiments revealed that Vapyrin-bodies have an endosomal identity with trans-Golgi features, and that VAPYRIN interacts with a symbiotic R-SNARE of the VAMP721 family, that localizes to the same compartment.},
}
@article {pmid31231333,
year = {2019},
author = {Miozzi, L and Vaira, AM and Catoni, M and Fiorilli, V and Accotto, GP and Lanfranco, L},
title = {Arbuscular Mycorrhizal Symbiosis: Plant Friend or Foe in the Fight Against Viruses?.},
journal = {Frontiers in microbiology},
volume = {10},
number = {},
pages = {1238},
doi = {10.3389/fmicb.2019.01238},
pmid = {31231333},
issn = {1664-302X},
abstract = {Plant roots establish interactions with several beneficial soil microorganisms including arbuscular mycorrhizal fungi (AMF). In addition to promoting plant nutrition and growth, AMF colonization can prime systemic plant defense and enhance tolerance to a wide range of environmental stresses and below-ground pathogens. A protective effect of the AMF against above-ground pathogens has also been described in different plant species, but it seems to largely rely on the type of attacker. Viruses are obligate biotrophic pathogens able to infect a large number of plant species, causing massive losses in crop yield worldwide. Despite their economic importance, information on the effect of the AM symbiosis on viral infection is limited and not conclusive. However, several experimental evidences, obtained under controlled conditions, show that AMF colonization may enhance viral infection, affecting susceptibility, symptomatology and viral replication, possibly related to the improved nutritional status and to the delayed induction of pathogenesis-related proteins in the mycorrhizal plants. In this review, we give an overview of the impact of the AMF colonization on plant infection by pathogenic viruses and summarize the current knowledge of the underlying mechanisms. For the cases where AMF colonization increases the susceptibility of plants to viruses, the term &quot;mycorrhiza-induced susceptibility&quot; (MIS) is proposed.},
}
@article {pmid31230564,
year = {2019},
author = {Liu, H and Senthilkumar, R and Ma, G and Zou, Q and Zhu, K and Shen, X and Tian, D and Hua, MS and Oelmüller, R and Yeh, KW},
title = {Piriformospora indica-induced phytohormone changes and root colonization strategies are highly host-specific.},
journal = {Plant signaling &amp; behavior},
volume = {14},
number = {9},
pages = {1632688},
doi = {10.1080/15592324.2019.1632688},
pmid = {31230564},
issn = {1559-2324},
abstract = {Piriformospora indica, an endophytic fungus of Sebacinales, has a wide host range and promotes the performance of mono- and eudicot plants. Here, we compare the interaction of P. indica with the roots of seven host plants (Anthurium andraeanum, Arabidopsis thaliana, Brassica campestris, Lycopersicon esculentum, Oncidium orchid, Oryza sativa, and Zea mays). Microscopical analyses showed that the colonization time and the mode of hyphal invasion into the roots differ in the symbiotic interactions. Substantial differences between the species were also observed for the levels and accumulation of jasmonate (JA) and gibberellin (GA) and the transcript levels for genes involved in their syntheses. No obvious correlation could be detected between the endogenous JA and/or GA levels and the time point of root colonization in a given plant species. Our results suggest that root colonization strategies and changes in the two phytohormone levels are highly host-specific.},
}
@article {pmid31230256,
year = {2019},
author = {Petrzik, K},
title = {Evolutionary forces at work in partitiviruses.},
journal = {Virus genes},
volume = {},
number = {},
pages = {},
doi = {10.1007/s11262-019-01680-0},
pmid = {31230256},
issn = {1572-994X},
support = {MEMOBIc//Ministerstvo Školství, Mládeže a Tělovýchovy/ ; RVO60077344//Akademie Věd České Republiky/ ; },
abstract = {The family Partitiviridae consists of dsRNA viruses with genome separated into two segments and encoding replicase and capsid protein only. We examined the nucleotide diversity expressed as the ratio dN/dS of nonsynonymous and synonymous substitutions, which has been calculated for 12 representative viruses of all five genera of partitiviruses. We can state that strong purifying selection works on both the RdRp and CP genes and propose that putative positive selection occurs also on the RdRp genes in two viruses. Among the 95 evaluated viruses, wherein both segments had been sequenced, 8 viruses in betapartitiviruses and 9 in alphapartitiviruses were identified as reassortment candidates because they differ extremely in their CP identity even as they are related in terms of RdRp. Furthermore, there are indications that reassortants are present among isolates of different viruses.},
}
@article {pmid31229798,
year = {2019},
author = {Roper, C and Castro, C and Ingel, B},
title = {Xylella fastidiosa: bacterial parasitism with hallmarks of commensalism.},
journal = {Current opinion in plant biology},
volume = {50},
number = {},
pages = {140-147},
doi = {10.1016/j.pbi.2019.05.005},
pmid = {31229798},
issn = {1879-0356},
abstract = {All organisms evolve in the presence of other organisms and these intimate associations are major drivers of evolution. Broadly speaking, these interactions are considered symbioses and can take on a full range of positive, negative or seemingly neutral interactions. Just two examples of these symbiotic interactions are parasitism and commensalism. Parasitism results in one partner benefitting while one partner suffers adverse consequences. Commensalism is a form of symbiosis where one partner benefits and the other partner is neutrally affected. Research efforts are more often focused on understanding parasitic symbioses related to disease, hence, much research is performed on identifying virulence factors to understand the fundamentals of pathogenesis. In turn, much less is understood about the fundamentals of commensal relationships. Here, we will take an introspective look at the plant-associated bacterium, Xylella fastidiosa. In some of its many plant hosts, this bacterium participates in seemingly commensal relationships while in other hosts, it causes devastating diseases that result in epidemics, making it a good model for exploring the determinants of where bacteria fall on the spectrum of parasitic and commensal relationships from both the microbial and the plant host perspective. Recent discoveries in how pathogenic X. fastidiosa imposes self-limiting behaviors upon itself indicate that even in its parasitic form, X. fastidiosa displays hallmarks of a commensal lifestyle. Understanding how commensalism can 'go wrong' and manifest into pathologies in specific hosts is a useful vantage point from which to study the determinants of virulence and pathogenicity.},
}
@article {pmid31229565,
year = {2019},
author = {Zhang, R and Yang, Y and Wang, J and Lin, Y and Yan, Y},
title = {Synthetic symbiosis combining plasmid displacement enables rapid construction of phenotype-stable strains.},
journal = {Metabolic engineering},
volume = {55},
number = {},
pages = {85-91},
doi = {10.1016/j.ymben.2019.06.011},
pmid = {31229565},
issn = {1096-7184},
abstract = {Plasmid-based microbial systems have been a major workhorse for chemical and pharmaceutical production. The biosafety issues and elevated industrial cost of antibiotic usage have led to the development of alternative strategies for plasmid selection and maintenance. Such strategies, including auxotrophy complementation, post-segregational killing, operator-repressor and RNA-based interactions often require extensive engineering of various elements and may result in extra metabolic burden in the cells. Herein, we report a design of synthetic symbiosis combining plasmid displacement to construct a phenotype-stable microbial system. By sequestrating an endogenous essential gene folP, cells obtained long-term plasmid maintenance with minimum cost. The phenotype performance was also inherited for up to 80 generations demonstrated by the production of salicylic acid in Escherichia coli. Meanwhile, the temperature-induced curing method of the intermediate plasmids enables rapid engineering. This design can lead to broad applications as a reliable and convenient plasmid-based expression system.},
}
@article {pmid31228837,
year = {2019},
author = {Dhaouefi, Z and Toledo-Cervantes, A and Ghedira, K and Chekir-Ghedira, L and Muñoz, R},
title = {Decolorization and phytotoxicity reduction in an innovative anaerobic/aerobic photobioreactor treating textile wastewater.},
journal = {Chemosphere},
volume = {234},
number = {},
pages = {356-364},
doi = {10.1016/j.chemosphere.2019.06.106},
pmid = {31228837},
issn = {1879-1298},
abstract = {The potential of a novel anaerobic/aerobic algal-bacterial photobioreactor for the treatment of synthetic textile wastewater (STWW) was here assessed. Algal-bacterial symbiosis supported total organic carbon, nitrogen and phosphorous removal efficiencies of 78 ± 2%, 47 ± 2% and 26 ± 2%, respectively, at a hydraulic retention time (HRT) of 8 days. A decrease in the HRT from 8 to 4 and 2 days resulted in a slight decrease in organic carbon and phosphate removal, but a sharp decrease in nitrogen removal. Moreover, an efficient decolorization of 99 ± 1% and 96 ± 3% for disperse orange-3 and of disperse blue-1, respectively, was recorded. The effective STWW treatment supported by the anaerobic/aerobic algal-bacterial photobioreactor was confirmed by the reduction in wastewater toxicity towards Raphanus sativus seed germination and growth. These results highlighted the potential of this innovative algal-bacterial photobioreactor configuration for the treatment of textile wastewater and water reuse.},
}
@article {pmid31227910,
year = {2019},
author = {Babadi, M and Zalaghi, R and Taghavi, M},
title = {A non-toxic polymer enhances sorghum-mycorrhiza symbiosis for bioremediation of Cd.},
journal = {Mycorrhiza},
volume = {29},
number = {4},
pages = {375-387},
doi = {10.1007/s00572-019-00902-5},
pmid = {31227910},
issn = {1432-1890},
support = {96/3/02/16670//Shahid Chamran University of Ahvaz/ ; },
abstract = {In this study, the effect of a mycorrhizal symbiosis on the translocation of Cd from Cd-polluted soil to sorghum roots was investigated using rhizoboxes. A factorial experiment (two factors including fungus inoculation and Cd contamination) in a completely randomized design with three replicates was performed. In the rhizobox rhizosphere compartment, plants were cultivated in uncontaminated soil and mycorrhizal inoculation (inoculated with Claroideoglomus etunicatum or non-inoculated) was performed, and in the other compartment, the soil was contaminated with Cadmium (Cd) at one of three levels (0, 100 mg kg-1 using a non-toxic organic polymer (poly (N-vinyl succinate))-Cd, or 100 mg kg-1 using Cd-nitrate). Cd pollution resulted in a significant decrease in shoot dry weight (from 7.52 to 6.18 and 6.68 g pot-1, from control to polymer-Cd and nitrate-Cd respectively), root mycorrhizal colonization (from 32.33% to 8.16% and 8.33%), shoot phosphorus concentration (from 3.14 to 2.80 and 2.76 g kg-1), and soil carbohydrate (from 12.05 to 10.74 and 10.24 mg g-1), and also resulted in significant increases in soil glomalin (from 595.55 to 660.52 and 690.39 μg g-1). The use of mycorrhizal fungi increased the glomalin content of the soil and improved the studied parameters. The results revealed the key role of Claroideoglomus etunicatum in translocation of Cd in the rhizobox and also in precise control of Cd concentration of plant tissues (increase or decrease of them depending on Cd composition and Cd availability). Poly(N-vinyl succinate) increased Cd availability and Cd concentration of shoot tissue (5.19 mg kg-1) compared to nitrate-Cd (3.68 mg kg-1) and could be recommended for improving phytoremediation.},
}
@article {pmid31227866,
year = {2019},
author = {Mei, YZ and Zhu, YL and Huang, PW and Yang, Q and Dai, CC},
title = {Strategies for gene disruption and expression in filamentous fungi.},
journal = {Applied microbiology and biotechnology},
volume = {103},
number = {15},
pages = {6041-6059},
doi = {10.1007/s00253-019-09953-2},
pmid = {31227866},
issn = {1432-0614},
support = {2017YFD0800705//Key Technologies Research and Development Program/ ; Project No31570491//National Natural Science Foundation of China (CN)/ ; },
abstract = {Filamentous fungi can produce many valuable secondary metabolites; among these fungi, endophytic fungi play an ecological role in mutualistic symbiosis with plants, including promoting plant growth, disease resistance, and stress resistance. However, the biosynthesis of most secondary metabolites remains unclear, and knowledge of the interaction mechanisms between endophytes and plants is still limited, especially for some novel fungi, due to the lack of genetic manipulation tools for novel species. Herein, we review the newly discovered strategies of gene disruption, such as the CRISPR-Cas9 system, the site-specific recombination Cre/loxP system, and the I-SceI endonuclease-mediated system in filamentous fungi. Gene expression systems contain using integration of target genes into the genome, host-dependent expression cassette construction depending on the host, a host-independent, universal expression system independent of the host, and reporter-guided gene expression for filamentous fungi. Furthermore, the Newly CRISPRi, CRISPRa, and the selection markers were also discussed for gene disruption and gene expression were also discussed. These studies lay the foundation for the biosynthesis of secondary metabolites in these organisms and aid in understanding the ecological function of filamentous fungi.},
}
@article {pmid31222171,
year = {2019},
author = {Edgcomb, V},
title = {Symbiotic magnetic motility.},
journal = {Nature microbiology},
volume = {4},
number = {7},
pages = {1066-1067},
doi = {10.1038/s41564-019-0489-3},
pmid = {31222171},
issn = {2058-5276},
mesh = {Bacteria ; *Eukaryota ; *Symbiosis ; },
}
@article {pmid31219214,
year = {2019},
author = {Muletz-Wolz, CR and Kurata, NP and Himschoot, EA and Wenker, ES and Quinn, EA and Hinde, K and Power, ML and Fleischer, RC},
title = {Diversity and temporal dynamics of primate milk microbiomes.},
journal = {American journal of primatology},
volume = {},
number = {},
pages = {e22994},
doi = {10.1002/ajp.22994},
pmid = {31219214},
issn = {1098-2345},
support = {RR019970/GF/NIH HHS/United States ; //Directorate for Biological Sciences/ ; //National Institutes of Health/ ; DDIG 0525025//NSF/ ; R24 OD010962/OD/NIH HHS/United States ; R01 DK077639/DK/NIDDK NIH HHS/United States ; R24OD020347//Smithsonian Competitive Grant for Science/ ; //American Society of Primatologists/ ; DDIG: 0746320//NSF/ ; RR000169/GF/NIH HHS/United States ; DK77639//John Capitanio and the California National Primate Research Center/ ; },
abstract = {Milk is inhabited by a community of bacteria and is one of the first postnatal sources of microbial exposure for mammalian young. Bacteria in breast milk may enhance immune development, improve intestinal health, and stimulate the gut-brain axis for infants. Variation in milk microbiome structure (e.g., operational taxonomic unit [OTU] diversity, community composition) may lead to different infant developmental outcomes. Milk microbiome structure may depend on evolutionary processes acting at the host species level and ecological processes occurring over lactation time, among others. We quantified milk microbiomes using 16S rRNA high-throughput sequencing for nine primate species and for six primate mothers sampled over lactation. Our data set included humans (Homo sapiens, Philippines and USA) and eight nonhuman primate species living in captivity (bonobo [Pan paniscus], chimpanzee [Pan troglodytes], western lowland gorilla [Gorilla gorilla gorilla], Bornean orangutan [Pongo pygmaeus], Sumatran orangutan [Pongo abelii], rhesus macaque [Macaca mulatta], owl monkey [Aotus nancymaae]) and in the wild (mantled howler monkey [Alouatta palliata]). For a subset of the data, we paired microbiome data with nutrient and hormone assay results to quantify the effect of milk chemistry on milk microbiomes. We detected a core primate milk microbiome of seven bacterial OTUs indicating a robust relationship between these bacteria and primate species. Milk microbiomes differed among primate species with rhesus macaques, humans and mantled howler monkeys having notably distinct milk microbiomes. Gross energy in milk from protein and fat explained some of the variations in microbiome composition among species. Microbiome composition changed in a predictable manner for three primate mothers over lactation time, suggesting that different bacterial communities may be selected for as the infant ages. Our results contribute to understanding ecological and evolutionary relationships between bacteria and primate hosts, which can have applied benefits for humans and endangered primates in our care.},
}
@article {pmid31218790,
year = {2019},
author = {Khatabi, B and Gharechahi, J and Ghaffari, MR and Liu, D and Haynes, PA and McKay, MJ and Mirzaei, M and Salekdeh, GH},
title = {Plant-Microbe Symbiosis: What Has Proteomics Taught Us?.},
journal = {Proteomics},
volume = {19},
number = {16},
pages = {e1800105},
doi = {10.1002/pmic.201800105},
pmid = {31218790},
issn = {1615-9861},
abstract = {Beneficial microbes have a positive impact on the productivity and fitness of the host plant. A better understanding of the biological impacts and underlying mechanisms by which the host derives these benefits will help to address concerns around global food production and security. The recent development of omics-based technologies has broadened our understanding of the molecular aspects of beneficial plant-microbe symbiosis. Specifically, proteomics has led to the identification and characterization of several novel symbiosis-specific and symbiosis-related proteins and post-translational modifications that play a critical role in mediating symbiotic plant-microbe interactions and have helped assess the underlying molecular aspects of the symbiotic relationship. Integration of proteomic data with other &quot;omics&quot; data can provide valuable information to assess hypotheses regarding the underlying mechanism of symbiosis and help define the factors affecting the outcome of symbiosis. Herein, an update is provided on the current and potential applications of symbiosis-based &quot;omic&quot; approaches to dissect different aspects of symbiotic plant interactions. The application of proteomics, metaproteomics, and secretomics as enabling approaches for the functional analysis of plant-associated microbial communities is also discussed.},
}
@article {pmid31218402,
year = {2019},
author = {Motaharpoor, Z and Taheri, H and Nadian, H},
title = {Rhizophagus irregularis modulates cadmium uptake, metal transporter, and chelator gene expression in Medicago sativa.},
journal = {Mycorrhiza},
volume = {29},
number = {4},
pages = {389-395},
doi = {10.1007/s00572-019-00900-7},
pmid = {31218402},
issn = {1432-1890},
abstract = {Arbuscular mycorrhizal fungi (AMF) are considered a potential biotechnological tool for mitigating heavy metal (HM) toxicity. A greenhouse experiment was conducted to evaluate the impacts of the AM fungus Rhizophagus irregularis on cadmium (Cd) uptake, mycorrhizal colonization, and some plant growth parameters of Medicago sativa (alfalfa) in Cd-polluted soils. In addition, expression of two metal chelators (MsPCS1 (phytochelatin synthase) and MsMT2 (metallothionein)) and two metal transporter genes (MsIRT1 and MsNramp1) was analyzed using quantitative real-time PCR (qRT-PCR). Cd addition had a significant negative effect on mycorrhizal colonization. However, AMF symbiosis promoted the accumulation of biomass under both stressed and unstressed conditions compared with non-mycorrhizal (NM) plants. Results also showed that inoculation with R. irregularis significantly reduced shoot Cd concentration in polluted soils. Transcripts abundance of MsPCS1, MsMT2, MsIRT1, and MsNRAMP1 genes were downregulated compared with NM plants indicating that metal sequestration within hyphal fungi probably made Cd concentration insufficient in root cells for induction of these genes. These results suggest that reduction of shoot Cd concentration in M. sativa colonized by R. irregularis could be a promising strategy for safe production of this plant in Cd-polluted soils.},
}
@article {pmid31218384,
year = {2019},
author = {Della Mónica, IF and Godeas, AM and Scervino, JM},
title = {In Vivo Modulation of Arbuscular Mycorrhizal Symbiosis and Soil Quality by Fungal P Solubilizers.},
journal = {Microbial ecology},
volume = {},
number = {},
pages = {},
doi = {10.1007/s00248-019-01396-6},
pmid = {31218384},
issn = {1432-184X},
support = {PICT 2012 0285//Agencia Nacional de Promoción Científica y Tecnológica/ ; },
abstract = {Phosphorus (P) is an essential nutrient with low bioavailability in soils for plant growth. The use of P solubilization fungi (PSF) has arisen as an eco-friendly strategy to increase this nutrient's bioavailability. The effect of PSF inoculation and its combination with P-transporting organisms (arbuscular mycorrhizal fungi, AMF) on plant growth has been previously studied. However, these studies did not evaluate the combined effect of PSF and AMF inoculation on plant growth, symbiosis, and soil quality. Therefore, the aim of this study is to assess the impact of PSF on the AMF-wheat symbiosis establishment and efficiency, considering the effect on plant growth and soil quality. We performed a greenhouse experiment with wheat under different treatments (+/-AMF: Rhizophagus irregularis; +/-PSF strains: Talaromyces flavus, T. helicus L7B, T. helicus N24, and T. diversus) and measured plant growth, AMF root colonization, symbiotic efficiency, and soil quality indicators. No interaction between PSF and R. irregularis was found in wheat growth, showcasing that their combination is not better than single inoculation. T. helicus strains did not interfere with the AMF-wheat symbiosis establishment, while T. diversus and T. flavus decreased it. The symbiotic efficiency was increased by T. flavus and T. helicus N24, and unchanged with T. helicus L7B and T. diversus inoculation. The soil quality indicators were higher with microbial co-inoculation, particularly the alkaline phosphatases parameter, showing the beneficial role of fungi in soil. This work highlights the importance of microbial interactions in the rhizosphere for crop sustainability and soil quality improvement, assessing the effects of PSF on AMF-wheat symbiosis.},
}
@article {pmid31217550,
year = {2019},
author = {Otani, S and Challinor, VL and Kreuzenbeck, NB and Kildgaard, S and Krath Christensen, S and Larsen, LLM and Aanen, DK and Rasmussen, SA and Beemelmanns, C and Poulsen, M},
title = {Disease-free monoculture farming by fungus-growing termites.},
journal = {Scientific reports},
volume = {9},
number = {1},
pages = {8819},
doi = {10.1038/s41598-019-45364-z},
pmid = {31217550},
issn = {2045-2322},
support = {DNRF57//Danmarks Grundforskningsfond (Danish National Research Foundation)/ ; CRC 1127 ChemBioSys//Deutsche Forschungsgemeinschaft (German Research Foundation)/ ; VKR10101//Villum Fonden (Villum Foundation)/ ; },
abstract = {Fungus-growing termites engage in an obligate mutualistic relationship with Termitomyces fungi, which they maintain in monocultures on specialised fungus comb structures, without apparent problems with infectious diseases. While other fungi have been reported in the symbiosis, detailed comb fungal community analyses have been lacking. Here we use culture-dependent and -independent methods to characterise fungus comb mycobiotas from three fungus-growing termite species (two genera). Internal Transcribed Spacer (ITS) gene analyses using 454 pyrosequencing and Illumina MiSeq showed that non-Termitomyces fungi were essentially absent in fungus combs, and that Termitomyces fungal crops are maintained in monocultures as heterokaryons with two or three abundant ITS variants in a single fungal strain. To explore whether the essential absence of other fungi within fungus combs is potentially due to the production of antifungal metabolites by Termitomyces or comb bacteria, we performed in vitro assays and found that both Termitomyces and chemical extracts of fungus comb material can inhibit potential fungal antagonists. Chemical analyses of fungus comb material point to a highly complex metabolome, including compounds with the potential to play roles in mediating these contaminant-free farming conditions in the termite symbiosis.},
}
@article {pmid31217361,
year = {2019},
author = {Shinohara, A and Nohara, M and Kondo, Y and Jogahara, T and Nagura-Kato, GA and Izawa, M and Koshimoto, C},
title = {Comparison of the gut microbiotas of laboratory and wild Asian house shrews (Suncus murinus) based on cloned 16S rRNA sequences.},
journal = {Experimental animals},
volume = {},
number = {},
pages = {},
doi = {10.1538/expanim.19-0021},
pmid = {31217361},
issn = {1881-7122},
abstract = {The Asian house shrew, Suncus murinus, is an insectivore (Eulipotyphla, Mammalia) and an important laboratory animal for life-science studies. The gastrointestinal tract of Suncus is simple: the length of the entire intestine is very short relative to body size, the large intestine is quite short, and there are no fermentative chambers such as the forestomach or cecum. These features imply that Suncus has a different nutritional physiology from those of humans and mice, but little is known about whether Suncus utilizes microbial fermentation in the large (LI) or small (SI) intestine. In addition, domestication may affect the gastrointestinal microbial diversity of Suncus. Therefore, we compared the gastrointestinal microbial diversity of Suncus between laboratory and wild Suncus and between the SI and LI (i.e., four groups: Lab-LI, Lab-SI, Wild-LI, and Wild-SI) using bacterial 16S rRNA gene library sequencing analyses with a sub-cloning method. We obtained 759 cloned sequences (176, 174, 195, and 214 from the Lab-LI, Lab-SI, Wild-LI, and Wild-SI samples, respectively), which revealed that the gastrointestinal microbiota of Suncus is rich in Firmicutes (mostly lactic acid bacteria), with few Bacteroidetes. We observed different bacterial communities according to intestinal region in laboratory Suncus, but not in wild Suncus. Furthermore, the gastrointestinal microbial diversity estimates were lower in laboratory Suncus than in wild Suncus. These results imply that Suncus uses lactic acid fermentation in the gut, and that the domestication process altered the gastrointestinal bacterial diversity.},
}
@article {pmid31216282,
year = {2019},
author = {Sieber, M and Pita, L and Weiland-Bräuer, N and Dirksen, P and Wang, J and Mortzfeld, B and Franzenburg, S and Schmitz, RA and Baines, JF and Fraune, S and Hentschel, U and Schulenburg, H and Bosch, TCG and Traulsen, A},
title = {Neutrality in the Metaorganism.},
journal = {PLoS biology},
volume = {17},
number = {6},
pages = {e3000298},
doi = {10.1371/journal.pbio.3000298},
pmid = {31216282},
issn = {1545-7885},
abstract = {Almost all animals and plants are inhabited by diverse communities of microorganisms, the microbiota, thereby forming an integrated entity, the metaorganism. Natural selection should favor hosts that shape the community composition of these microbes to promote a beneficial host-microbe symbiosis. Indeed, animal hosts often pose selective environments, which only a subset of the environmentally available microbes are able to colonize. How these microbes assemble after colonization to form the complex microbiota is less clear. Neutral models are based on the assumption that the alternatives in microbiota community composition are selectively equivalent and thus entirely shaped by random population dynamics and dispersal. Here, we use the neutral model as a null hypothesis to assess microbiata composition in host organisms, which does not rely on invoking any adaptive processes underlying microbial community assembly. We show that the overall microbiota community structure from a wide range of host organisms, in particular including previously understudied invertebrates, is in many cases consistent with neutral expectations. Our approach allows to identify individual microbes that are deviating from the neutral expectation and are therefore interesting candidates for further study. Moreover, using simulated communities, we demonstrate that transient community states may play a role in the deviations from the neutral expectation. Our findings highlight that the consideration of neutral processes and temporal changes in community composition are critical for an in-depth understanding of microbiota-host interactions.},
}
@article {pmid31216220,
year = {2019},
author = {Plett, KL and Raposo, AE and Anderson, IC and Piller, SC and Plett, JM},
title = {Protein Arginine Methyltransferase Expression Affects Ectomycorrhizal Symbiosis and the Regulation of Hormone Signaling Pathways.},
journal = {Molecular plant-microbe interactions : MPMI},
volume = {},
number = {},
pages = {MPMI01190007R},
doi = {10.1094/MPMI-01-19-0007-R},
pmid = {31216220},
issn = {0894-0282},
abstract = {The genomes of all eukaryotic organisms, from small unicellular yeasts to humans, include members of the protein arginine methyltransferase (PRMT) family. These enzymes affect gene transcription, cellular signaling, and function through the posttranslational methylation of arginine residues. Mis-regulation of PRMTs results in serious developmental defects, disease, or death, illustrating the importance of these enzymes to cellular processes. Plant genomes encode almost the full complement of PRMTs found in other higher organisms, plus an additional PRMT found uniquely in plants, PRMT10. Here, we investigate the role of these highly conserved PRMTs in a process that is unique to perennial plants-the development of symbiosis with ectomycorrhizal fungi. We show that PRMT expression and arginine methylation is altered in the roots of the model tree Eucalyptus grandis by the presence of its ectomycorrhizal fungal symbiont Pisolithus albus. Further, using transgenic modifications, we demonstrate that E. grandis-encoded PRMT1 and PRMT10 have important but opposing effects in promoting this symbiosis. In particular, the plant-specific EgPRMT10 has a potential role in the expression of plant hormone pathways during the colonization process and its overexpression reduces fungal colonization success.},
}
@article {pmid31215669,
year = {2019},
author = {Page, CE and Leggat, W and Heron, SF and Choukroun, SM and Lloyd, J and Ainsworth, TD},
title = {Seeking Resistance in Coral Reef Ecosystems: The Interplay of Biophysical Factors and Bleaching Resistance under a Changing Climate: The Interplay of a Reef's Biophysical Factors Can Mitigate the Coral Bleaching Response.},
journal = {BioEssays : news and reviews in molecular, cellular and developmental biology},
volume = {41},
number = {7},
pages = {e1800226},
doi = {10.1002/bies.201800226},
pmid = {31215669},
issn = {1521-1878},
support = {NA14NES4320003//National Oceanic and Atmospheric Administration/ ; DP180103199//Australian Research Council/ ; NA14NES4320003//NOAA/ ; DP180103199//Australian Research Council Discovery Project/ ; },
abstract = {If we are to ensure the persistence of species in an increasingly warm world, of interest is the identification of drivers that affect the ability of an organism to resist thermal stress. Underpinning any organism's capacity for resistance is a complex interplay between biological and physical factors occurring over multiple scales. Tropical coral reefs are a unique system, in that their function is dependent upon the maintenance of a coral-algal symbiosis that is directly disrupted by increases in water temperature. A number of physical factors have been identified as affecting the biological responses of the coral organism under broadscale thermal anomalies. One such factor is water flow, which is capable of modulating both organismal metabolic functioning and thermal environments. Understanding the physiological and hydrodynamic drivers of organism response to thermal stress improves predictive capabilities and informs targeted management responses, thereby increasing the resilience of reefs into the future.},
}
@article {pmid31215061,
year = {2019},
author = {Law, SR},
title = {The genetic program at the root of the biological stock exchange.},
journal = {Physiologia plantarum},
volume = {166},
number = {3},
pages = {709-711},
doi = {10.1111/ppl.12980},
pmid = {31215061},
issn = {1399-3054},
mesh = {Gene Expression Regulation, Plant ; Mycorrhizae/*physiology ; Plant Roots/*microbiology ; Symbiosis/physiology ; },
abstract = {Beneath the gardens, farmlands and forest floors that surround us, a hidden world blooms in careful cooperation and intense competition. The mutualistic symbiosis of the thread-like hyphae of fungi and plant roots (collectively termed mycorrhizae from the Greek mýkēs - meaning 'fungus', and rhiza - for 'root') is present in the vast majority of plant species. As with most intimate relationships, this symbiosis functions on a principle of 'give and take'. As an autotroph, the plant is able to synthesize all the sugars it requires through photosynthesis; however, its immobility hinders its capacity to forage for nutrients vital for its growth and survival. With an expansive network of hyphae, the heterotrophic fungus is able to locate and remobilize water and nutrients, such as phosphorus (P) and nitrogen (N), and barter them for precious sugars with the plant. An article in this issue of Physiologia Plantarum (Zhao et al. 2019) describes alterations in the genetic programming that takes place in the plant root upon the establishment of this fascinating relationship, which has profound implications for plant productivity and soil management methods.},
}
@article {pmid31214691,
year = {2019},
author = {Phillips, AJ and Dornburg, A and Zapfe, KL and Anderson, FE and James, SW and Erséus, C and Moriarty Lemmon, E and Lemmon, AR and Williams, BW},
title = {Phylogenomic Analysis of a Putative Missing Link Sparks Reinterpretation of Leech Evolution.},
journal = {Genome biology and evolution},
volume = {11},
number = {7},
pages = {1712-1722},
doi = {10.1093/gbe/evz120},
pmid = {31214691},
issn = {1759-6653},
abstract = {Leeches (Hirudinida) comprise a charismatic, yet often maligned group of organisms. Despite their ecological, economic, and medical importance, a general consensus on the phylogenetic relationships of major hirudinidan lineages is lacking. This absence of a consistent, robust phylogeny of early-diverging lineages has hindered our understanding of the underlying processes that enabled evolutionary diversification of this clade. Here, we used an anchored hybrid enrichment-based phylogenomic approach, capturing hundreds of loci to investigate phylogenetic relationships among major hirudinidan lineages and their closest living relatives. Our results suggest that a dramatic reinterpretation of early leech evolution is warranted. We recovered Branchiobdellida as sister to a clade that includes all major lineages of hirudinidans, but found Acanthobdella to be nested within Oceanobdelliformes. These results cast doubt on the utility of Acanthobdella as a &quot;missing link&quot; used to explain the origin of blood-feeding in hirudineans. Further, our results support a deep divergence between predominantly marine and freshwater lineages, while not supporting the reciprocal monophyly of jawed and proboscis-bearing leeches. To sum up, our phylogenomic resolution of early-diverging leeches provides a necessary foundation for illuminating the evolution of host-symbiont associations and key adaptations that have allowed leeches to colonize a wide diversity of habitats worldwide.},
}
@article {pmid31214211,
year = {2019},
author = {Billault-Penneteau, B and Sandré, A and Folgmann, J and Parniske, M and Pawlowski, K},
title = {Dryas as a Model for Studying the Root Symbioses of the Rosaceae.},
journal = {Frontiers in plant science},
volume = {10},
number = {},
pages = {661},
doi = {10.3389/fpls.2019.00661},
pmid = {31214211},
issn = {1664-462X},
abstract = {The nitrogen-fixing root nodule symbiosis is restricted to four plant orders: Fabales (legumes), Fagales, Cucurbitales and Rosales (Elaeagnaceae, Rhamnaceae, and Rosaceae). Interestingly all of the Rosaceae genera confirmed to contain nodulating species (i.e., Cercocarpus, Chamaebatia, Dryas, and Purshia) belong to a single subfamily, the Dryadoideae. The Dryas genus is particularly interesting from an evolutionary perspective because it contains closely related nodulating (Dryas drummondii) and non-nodulating species (Dryas octopetala). The close phylogenetic relationship between these two species makes Dryas an ideal model genus to study the genetic basis of nodulation by whole genome comparison and classical genetics. Therefore, we established methods for plant cultivation, transformation and DNA extraction for these species. We optimized seed surface sterilization and germination methods and tested growth protocols ranging from pots and Petri dishes to a hydroponic system. Transgenic hairy roots were obtained by adapting Agrobacterium rhizogenes-based transformation protocols for Dryas species. We compared several DNA extraction protocols for their suitability for subsequent molecular biological analysis. Using CTAB extraction, reproducible PCRs could be performed, but CsCl gradient purification was essential to obtain DNA in sufficient purity for high quality de novo genome sequencing of both Dryas species. Altogether, we established a basic toolkit for the culture, transient transformation and genetic analysis of Dryas sp.},
}
@article {pmid31214134,
year = {2019},
author = {Medrano, E and Merselis, DG and Bellantuono, AJ and Rodriguez-Lanetty, M},
title = {Proteomic Basis of Symbiosis: A Heterologous Partner Fails to Duplicate Homologous Colonization in a Novel Cnidarian- Symbiodiniaceae Mutualism.},
journal = {Frontiers in microbiology},
volume = {10},
number = {},
pages = {1153},
doi = {10.3389/fmicb.2019.01153},
pmid = {31214134},
issn = {1664-302X},
abstract = {Reef corals and sea anemones form symbioses with unicellular symbiotic dinoflagellates. The molecular circumventions that underlie the successful intracellular colonization of hosts by symbionts are still largely unknown. We conducted proteomic analyses to determine molecular differences of Exaiptasia pallida anemones colonized by physiologically different symbiont species, in comparison with symbiont-free (aposymbiotic) anemones. We compared one homologous species, Symbiodinium linucheae, that is natively associated with the clonal Exaiptasia strain (CC7) to another heterologous species, Durusdinium trenchii, a thermally tolerant species that colonizes numerous coral species. This approach allowed the discovery of a core set of host genes that are differentially regulated as a function of symbiosis regardless of symbiont species. The findings revealed that symbiont colonization at higher densities requires circumvention of the host cellular immunological response, enhancement of ammonium regulation, and suppression of phagocytosis after a host cell in colonized. Furthermore, the heterologous symbionts failed to duplicate the same level of homologous colonization within the host, evidenced by substantially lower symbiont densities. This reduced colonization of D. trenchii correlated with its inability to circumvent key host systems including autophagy-suppressing modulators, cytoskeletal alteration, and isomerase activity. The larger capability of host molecular circumvention by homologous symbionts could be the result of a longer evolutionary history of host/symbiont interactions, which translates into a more finely tuned symbiosis. These findings are of great importance within the context of the response of reef corals to climate change since it has been suggested that coral may acclimatize to ocean warming by changing their dominant symbiont species.},
}
@article {pmid31213566,
year = {2019},
author = {Van Leuven, JT and Mao, M and Xing, DD and Bennett, GM and McCutcheon, JP},
title = {Cicada Endosymbionts Have tRNAs That Are Correctly Processed Despite Having Genomes That Do Not Encode All of the tRNA Processing Machinery.},
journal = {mBio},
volume = {10},
number = {3},
pages = {},
doi = {10.1128/mBio.01950-18},
pmid = {31213566},
issn = {2150-7511},
support = {P20 GM104420/GM/NIGMS NIH HHS/United States ; },
abstract = {Gene loss and genome reduction are defining characteristics of endosymbiotic bacteria. The most highly reduced endosymbiont genomes have lost numerous essential genes related to core cellular processes such as replication, transcription, and translation. Computational gene predictions performed for the genomes of the two bacterial symbionts of the cicada Diceroprocta semicincta, &quot;Candidatus Hodgkinia cicadicola&quot; (Alphaproteobacteria) and &quot;Ca Sulcia muelleri&quot; (Bacteroidetes), have found only 26 and 16 tRNA genes and 15 and 10 aminoacyl tRNA synthetase genes, respectively. Furthermore, the original &quot;Ca Hodgkinia cicadicola&quot; genome annotation was missing several essential genes involved in tRNA processing, such as those encoding RNase P and CCA tRNA nucleotidyltransferase as well as several RNA editing enzymes required for tRNA maturation. How these cicada endosymbionts perform basic translation-related processes remains unknown. Here, by sequencing eukaryotic mRNAs and total small RNAs, we show that the limited tRNA set predicted by computational annotation of &quot;Ca Sulcia muelleri&quot; and &quot;Ca Hodgkinia cicadicola&quot; is likely correct. Furthermore, we show that despite the absence of genes encoding tRNA processing activities in the symbiont genomes, symbiont tRNAs have correctly processed 5' and 3' ends and seem to undergo nucleotide modification. Surprisingly, we found that most &quot;Ca Hodgkinia cicadicola&quot; and &quot;Ca Sulcia muelleri&quot; tRNAs exist as tRNA halves. We hypothesize that &quot;Ca Sulcia muelleri&quot; and &quot;Ca Hodgkinia cicadicola&quot; tRNAs function in bacterial translation but require host-encoded enzymes to do so.IMPORTANCE The smallest bacterial genomes, in the range of about 0.1 to 0.5 million base pairs, are commonly found in the nutritional endosymbionts of insects. These tiny genomes are missing genes that encode proteins and RNAs required for the translation of mRNAs, one of the most highly conserved and important cellular processes. In this study, we found that the bacterial endosymbionts of cicadas have genomes which encode incomplete tRNA sets and lack genes required for tRNA processing. Nevertheless, we found that endosymbiont tRNAs are correctly processed at their 5' and 3' ends and, surprisingly, that mostly exist as tRNA halves. We hypothesize that the cicada host must supply its symbionts with these missing tRNA processing activities.},
}
@article {pmid31212139,
year = {2019},
author = {Müller, LM and Harrison, MJ},
title = {Phytohormones, miRNAs, and peptide signals integrate plant phosphorus status with arbuscular mycorrhizal symbiosis.},
journal = {Current opinion in plant biology},
volume = {50},
number = {},
pages = {132-139},
doi = {10.1016/j.pbi.2019.05.004},
pmid = {31212139},
issn = {1879-0356},
abstract = {Most land plant species engage in a beneficial interaction with arbuscular mycorrhizal fungi in order to increase mineral nutrient acquisition, in particular the major macronutrient phosphorus (P). Initiation, development, and maintenance of the symbiosis are largely under the control of the host plant and strongly influenced by the plants' P status. Recent advances reveal that phytohormones, microRNAs, and secreted peptides all regulate and integrate development of arbuscular mycorrhizal (AM) symbiosis with the P status of the plant. This occurs through a complex, multi-layered signaling network with crosstalk between phosphate (Pi) starvation signaling pathways and AM symbiosis signaling, and also via direct effects on the AM fungal symbiont. Multiple checkpoints allow the plant to fine-tune symbiosis based on its P status.},
}
@article {pmid31211975,
year = {2019},
author = {McCutcheon, JP and Lekberg, Y},
title = {Symbiosis: Fungi as Shrewd Trade Negotiators.},
journal = {Current biology : CB},
volume = {29},
number = {12},
pages = {R570-R572},
doi = {10.1016/j.cub.2019.05.002},
pmid = {31211975},
issn = {1879-0445},
abstract = {Symbiotic fungi associated with plant roots can shuttle a key nutrient through their hyphal network in response to resource inequality. This need-based transport optimizes trade conditions for carbon with plants.},
}
@article {pmid31208116,
year = {2019},
author = {Cui, C and Wang, H and Hong, L and Xu, Y and Zhao, Y and Zhou, C},
title = {MtBZR1 Plays an Important Role in Nodule Development in Medicago truncatula.},
journal = {International journal of molecular sciences},
volume = {20},
number = {12},
pages = {},
doi = {10.3390/ijms20122941},
pmid = {31208116},
issn = {1422-0067},
support = {ZR2018ZC0334//Major Program of Shandong Province Natural Science Foundation/ ; 2015CB943500//Ministry of Science and Technology of the People's Republic of China/ ; 31671507//National Natural Science Foundation of China/ ; 31371235//National Natural Science Foundation of China/ ; },
abstract = {Brassinosteroid (BR) is an essential hormone in plant growth and development. The BR signaling pathway was extensively studied, in which BRASSINAZOLE RESISTANT 1 (BZR1) functions as a key regulator. Here, we carried out a functional study of the homolog of BZR1 in Medicago truncatula R108, whose expression was induced in nodules upon Sinorhizobium meliloti 1021 inoculation. We identified a loss-of-function mutant mtbzr1-1 and generated 35S:MtBZR1 transgenic lines for further analysis at the genetic level. Both the mutant and the overexpression lines of MtBZR1 showed no obvious phenotypic changes under normal growth conditions. After S. meliloti 1021 inoculation, however, the shoot and root dry mass was reduced in mtbzr1-1 compared with the wild type, caused by partially impaired nodule development. The transcriptomic analysis identified 1319 differentially expressed genes in mtbzr1-1 compared with wild type, many of which are involved in nodule development and secondary metabolite biosynthesis. Our results demonstrate the role of MtBZR1 in nodule development in M. truncatula, shedding light on the potential role of BR in legume-rhizobium symbiosis.},
}
@article {pmid31207947,
year = {2019},
author = {Dominguez, H and Loret, EP},
title = {Ulva lactuca, A Source of Troubles and Potential Riches.},
journal = {Marine drugs},
volume = {17},
number = {6},
pages = {},
doi = {10.3390/md17060357},
pmid = {31207947},
issn = {1660-3397},
abstract = {Ulva lactuca is a green macro alga involved in devastating green tides observed worldwide. These green tides or blooms are a consequence of human activities. Ulva blooms occur mainly in shallow waters and the decomposition of this alga can produce dangerous vapors. Ulva lactuca is a species usually resembling lettuce, but genetic analyses demonstrated that other green algae with tubular phenotypes were U. lactuca clades although previously described as different species or even genera. The capacity for U. lactuca to adopt different phenotypes can be due to environment parameters, such as the degree of water salinity or symbiosis with bacteria. No efficient ways have been discovered to control these green tides, but the Mediterranean seas appear to be protected from blooms, which disappear rapidly in springtime. Ulva contains commercially valuable components, such as bioactive compounds, food or biofuel. The biomass due to this alga collected on beaches every year is beginning to be valorized to produce valuable compounds. This review describes different processes and strategies developed to extract these different valuable components.},
}
@article {pmid31204904,
year = {2019},
author = {Zou, H and Zhang, NN and Pan, Q and Zhang, JH and Chen, J and Wei, GH},
title = {Hydrogen Sulfide Promotes Nodulation and Nitrogen Fixation in Soybean-Rhizobia Symbiotic System.},
journal = {Molecular plant-microbe interactions : MPMI},
volume = {32},
number = {8},
pages = {972-985},
doi = {10.1094/MPMI-01-19-0003-R},
pmid = {31204904},
issn = {0894-0282},
mesh = {Gasotransmitters/pharmacology ; *Hydrogen Sulfide/pharmacology ; *Nitrogen Fixation/drug effects ; *Plant Root Nodulation/drug effects ; *Rhizobium/physiology ; *Soybeans/microbiology ; Symbiosis/drug effects ; },
abstract = {The rhizobium-legume symbiotic system is crucial for nitrogen cycle balance in agriculture. Hydrogen sulfide (H2S), a gaseous signaling molecule, may regulate various physiological processes in plants. However, whether H2S has regulatory effect in this symbiotic system remains unknown. Herein, we investigated the possible role of H2S in the symbiosis between soybean (Glycine max) and rhizobium (Sinorhizobium fredii). Our results demonstrated that an exogenous H2S donor (sodium hydrosulfide [NaHS]) treatment promoted soybean growth, nodulation, and nitrogenase (Nase) activity. Western blotting analysis revealed that the abundance of Nase component nifH was increased by NaHS treatment in nodules. Quantitative real-time polymerase chain reaction data showed that NaHS treatment upregulated the expressions of symbiosis-related genes nodA, nodC, and nodD of S. fredii. In addition, expression of soybean nodulation marker genes, including early nodulin 40 (GmENOD40), ERF required for nodulation (GmERN), nodulation signaling pathway 2b (GmNSP2b), and nodulation inception genes (GmNIN1a, GmNIN2a, and GmNIN2b), were upregulated. Moreover, the expressions of glutamate synthase (GmGOGAT), asparagine synthase (GmAS), nitrite reductase (GmNiR), ammonia transporter (GmSAT1), leghemoglobin (GmLb), and nifH involved in nitrogen metabolism were upregulated in NaHS-treated soybean roots and nodules. Together, our results suggested that H2S may act as a positive signaling molecule in the soybean-rhizobia symbiotic system and enhance the system's nitrogen fixation ability.},
}
@article {pmid31203796,
year = {2019},
author = {Ravindran, S and Tambe, AJ and Suthar, JK and Chahar, DS and Fernandes, JM and Desai, V},
title = {Nanomedicine: Bioavailability, Biotransformation and Biokinetics.},
journal = {Current drug metabolism},
volume = {20},
number = {7},
pages = {542-555},
doi = {10.2174/1389200220666190614150708},
pmid = {31203796},
issn = {1875-5453},
abstract = {BACKGROUND: Nanomedicine is increasingly used to treat various ailments. Biocompatibility of nanomedicine is primarily governed by its properties such as bioavailability, biotransformation and biokinetics. One of the major advantages of nanomedicine is enhanced bioavailability of drugs. Biotransformation of nanomedicine is important to understand the pharmacological effects of nanomedicine. Biokinetics includes both pharmacokinetics and toxicokinetics of nanomedicine. Physicochemical parameters of nanomaterials have extensive influence on bioavailability, biotransformation and biokinetics of nanomedicine.<br><br>METHODS: We carried out a structured peer-reviewed research literature survey and analysis using bibliographic databases.<br><br>RESULTS: Eighty papers were included in the review. Papers dealing with bioavailability, biotransformation and biokinetics of nanomedicine are found and reviewed. Bioavailability and biotransformation along with biokinetics are three major factors that determine the biological fate of nanomedicine. Extensive research work has been done for drugs of micron size but studies on nanomedicine are scarce. Therefore, more emphasis in this review is given on the bioavailability and biotransformation of nanomedicine along with biokinetics.<br><br>CONCLUSION: Bioavailability results based on various nanomedicine are summarized in the present work. Biotransformation of nanodrugs as well as nanoformulations is also the focus of this article. Both in vitro and in vivo biotransformation studies on nanodrugs and its excipients are necessary to know the effect of metabolites formed. Biokinetics of nanomedicine is captured in details that are complimentary to bioavailability and biotransformation. Nanomedicine has the potential to be developed as a personalized medicine once its physicochemical properties and its effect on biological system are well understood.},
}
@article {pmid31200330,
year = {2019},
author = {Jiang, J and Lu, Y},
title = {Metabolite profiling of Breviolum minutum in response to acidification.},
journal = {Aquatic toxicology (Amsterdam, Netherlands)},
volume = {213},
number = {},
pages = {105215},
doi = {10.1016/j.aquatox.2019.05.017},
pmid = {31200330},
issn = {1879-1514},
abstract = {Coral reefs are in significant decline globally due to climate change and environmental pollution. The ocean is becoming more acidic due to rising atmospheric pCO2, and ocean acidification is considered a major threat to coral reefs. However, little is known about the exact mechanism by which acidification impacts coral symbiosis. As an important component of the symbiotic association, to explore the responses of symbionts could greatly enhance our understanding of this issue. The present work aimed to identify metabolomic changes of Breviolum minutum in acidification (low pH) condition, and investigate the underlying mechanisms responsible. Liquid chromatography-tandem mass spectrometry (LC-MS/MS) was applied to determine metabolite profiles after exposure to ambient and acidic conditions. We analysed the resulting metabolite data, and acidification appeared to have little effect on photosynthetic parameters, but it inhibited growth. Marked alterations in metabolite pools were observed in response to acidification that may be important in acclimation to climate change. Acidification may affect the biosynthesis of amino acids and proteins, and thereby inhibit the growth of B. minutum. Metabolites identified using this approach provide targets for future analyses aimed at understanding the responses of Symbiodiniaceae to environmental disturbance.},
}
@article {pmid31197972,
year = {2019},
author = {Rader, B and McAnulty, SJ and Nyholm, SV},
title = {Persistent symbiont colonization leads to a maturation of hemocyte response in the Euprymna scolopes/Vibrio fischeri symbiosis.},
journal = {MicrobiologyOpen},
volume = {},
number = {},
pages = {e858},
doi = {10.1002/mbo3.858},
pmid = {31197972},
issn = {2045-8827},
support = {1R15GM119100/GF/NIH HHS/United States ; IOS-0958006//NSF/ ; IOS-155794//NSF/ ; },
abstract = {The binary association between the squid, Euprymna scolopes, and its symbiont, Vibrio fischeri, serves as a model system to study interactions between beneficial bacteria and the innate immune system. Previous research demonstrated that binding of the squid's immune cells, hemocytes, to V. fischeri is altered if the symbiont is removed from the light organ, suggesting that host colonization alters hemocyte recognition of V. fischeri. To investigate the influence of symbiosis on immune maturation during development, we characterized hemocyte binding and phagocytosis of V. fischeri and nonsymbiotic Vibrio harveyi from symbiotic (sym) and aposymbiotic (apo) juveniles, and wild-caught and laboratory-raised sym and apo adults. Our results demonstrate that while light organ colonization by V. fischeri did not alter juvenile hemocyte response, these cells bound a similar number of V. fischeri and V. harveyi yet phagocytosed only V. harveyi. Our results also indicate that long-term colonization altered the adult hemocyte response to V. fischeri but not V. harveyi. All hemocytes from adult squid, regardless of apo or sym state, both bound and phagocytosed a similar number of V. harveyi while hemocytes from both wild-caught and sym-raised adults bound significantly fewer V. fischeri, although more V. fischeri were phagocytosed by hemocytes from wild-caught animals. In contrast, hemocytes from apo-raised squid bound similar numbers of both V. fischeri and V. harveyi, although more V. harveyi cells were engulfed, suggesting that blood cells from apo-raised adults behaved similarly to juvenile hosts. Taken together, these data suggest that persistent colonization by the light organ symbiont is required for hemocytes to differentially bind and phagocytose V. fischeri. The cellular immune system of E. scolopes likely possesses multiple mechanisms at different developmental stages to promote a specific and life-long interaction with the symbiont.},
}
@article {pmid31197351,
year = {2019},
author = {Martínez-Medina, A and Pescador-Azofra, L and Terrón-Camero, L and Pozo, MJ and Romero-Puertas, MC},
title = {Nitric oxide shape plant-fungi interactions.},
journal = {Journal of experimental botany},
volume = {},
number = {},
pages = {},
doi = {10.1093/jxb/erz289},
pmid = {31197351},
issn = {1460-2431},
abstract = {In their complex environments, plants continuously interact with fungi. While many of those interactions are detrimental for plants and challenge plant capability for growth and survival, others are beneficial improving plant growth and stress tolerance. Accordingly, plants have evolved sophisticated mechanisms to restrict pathogenic interactions while promoting mutualistic relationships. Several studies demonstrated the importance of nitric oxide (NO) in the regulation of plant defence mounted against fungal pathogens. NO triggers a reprograming of defence related gene expression, the production of secondary metabolites with antimicrobial properties and the hypersensitive response. More recent evidences have further shown the regulation of NO during the establishment of plant-fungus mutualistic associations from early steps of the interaction. Indeed NO has been recently shown to be produced by the plant after the recognition of root fungal symbionts, and to be required for the optimal control of the mycorrhizal symbiosis. Although studies dealing with NO function in plant-fungus mutualistic associations are still scarce, experimental data support a different regulation patterns and functions for NO in plant interactions with pathogenic and mutualistic fungi. Here we review recent evidences about NO function in plant-fungus interactions, trying to identify common and differential patterns related to the fungus life-style and their impact on plant health.},
}
@article {pmid31197117,
year = {2019},
author = {Lipa, P and Vinardell, JM and Janczarek, M},
title = {Transcriptomic Studies Reveal that the Rhizobium leguminosarum Serine/Threonine Protein Phosphatase PssZ has a Role in the Synthesis of Cell-Surface Components, Nutrient Utilization, and Other Cellular Processes.},
journal = {International journal of molecular sciences},
volume = {20},
number = {12},
pages = {},
doi = {10.3390/ijms20122905},
pmid = {31197117},
issn = {1422-0067},
abstract = {Rhizobium leguminosarum bv. trifolii is a soil bacterium capable of establishing symbiotic associations with clover plants (Trifolium spp.). Surface polysaccharides, transport systems, and extracellular components synthesized by this bacterium are required for both the adaptation to changing environmental conditions and successful infection of host plant roots. The pssZ gene located in the Pss-I region, which is involved in the synthesis of extracellular polysaccharide, encodes a protein belonging to the group of serine/threonine protein phosphatases. In this study, a comparative transcriptomic analysis of R. leguminosarum bv. trifolii wild-type strain Rt24.2 and its derivative Rt297 carrying a pssZ mutation was performed. RNA-Seq data identified a large number of genes differentially expressed in these two backgrounds. Transcriptome profiling of the pssZ mutant revealed a role of the PssZ protein in several cellular processes, including cell signalling, transcription regulation, synthesis of cell-surface polysaccharides and components, and bacterial metabolism. In addition, we show that inactivation of pssZ affects the rhizobial ability to grow in the presence of different sugars and at various temperatures, as well as the production of different surface polysaccharides. In conclusion, our results identified a set of genes whose expression was affected by PssZ and confirmed the important role of this protein in the rhizobial regulatory network.},
}
@article {pmid31197001,
year = {2019},
author = {Mascuch, S and Kubanek, J},
title = {A marine chemical defense partnership.},
journal = {Science (New York, N.Y.)},
volume = {364},
number = {6445},
pages = {1034-1035},
doi = {10.1126/science.aax8964},
pmid = {31197001},
issn = {1095-9203},
mesh = {*Bacteria ; *Ecosystem ; *Symbiosis ; },
}
@article {pmid31196985,
year = {2019},
author = {Zan, J and Li, Z and Tianero, MD and Davis, J and Hill, RT and Donia, MS},
title = {A microbial factory for defensive kahalalides in a tripartite marine symbiosis.},
journal = {Science (New York, N.Y.)},
volume = {364},
number = {6445},
pages = {},
doi = {10.1126/science.aaw6732},
pmid = {31196985},
issn = {1095-9203},
support = {DP2 AI124441/AI/NIAID NIH HHS/United States ; },
abstract = {Chemical defense against predators is widespread in natural ecosystems. Occasionally, taxonomically distant organisms share the same defense chemical. Here, we describe an unusual tripartite marine symbiosis, in which an intracellular bacterial symbiont (&quot;Candidatus Endobryopsis kahalalidefaciens&quot;) uses a diverse array of biosynthetic enzymes to convert simple substrates into a library of complex molecules (the kahalalides) for chemical defense of the host, the alga Bryopsis sp., against predation. The kahalalides are subsequently hijacked by a third partner, the herbivorous mollusk Elysia rufescens, and employed similarly for defense. &quot;Ca E. kahalalidefaciens&quot; has lost many essential traits for free living and acts as a factory for kahalalide production. This interaction between a bacterium, an alga, and an animal highlights the importance of chemical defense in the evolution of complex symbioses.},
}
@article {pmid31195965,
year = {2019},
author = {Dreyer, J and Rautenbach, M and Booysen, E and van Staden, AD and Deane, SM and Dicks, LMT},
title = {Xenorhabdus khoisanae SB10 produces Lys-rich PAX lipopeptides and a Xenocoumacin in its antimicrobial complex.},
journal = {BMC microbiology},
volume = {19},
number = {1},
pages = {132},
doi = {10.1186/s12866-019-1503-x},
pmid = {31195965},
issn = {1471-2180},
support = {not applicable//National Research Foundation/ ; not applicable//BIOPEP Peptide fund/ ; },
abstract = {BACKGROUND: Xenorhabdus spp. live in close symbiosis with nematodes of the Steinernema genus. Steinernema nematodes infect an insect larva and release their symbionts into the haemocoel of the insect. Once released into the haemocoel, the bacteria produce bioactive compounds to create a semi-exclusive environment by inhibiting the growth of bacteria, yeasts and molds. The antimicrobial compounds thus far identified are xenocoumacins, xenortides, xenorhabdins, indole derivatives, xenoamicins, bicornutin and a number of antimicrobial peptides. The latter may be linear peptides such as the bacteriocins xenocin and xenorhabdicin, rhabdopeptides and cabanillasin, or cyclic, such as PAX lipopeptides, taxlllaids, xenobactin and szentiamide. Thus far, production of antimicrobial compounds have been reported for Xenorhabdus nematophila, Xenorhabdus budapestensis, Xenorhabdus cabanillasii, Xenorhabdus kozodoii, Xenorhabdus szentirmaii, Xenorhabdus doucetiae, Xenorhabdus mauleonii, Xenorhabdus indica and Xenorhabdus bovienii. Here we describe, for the first time, PAX lipopeptides and xenocoumacin 2 produced by Xenorhabdus khoisanae. These compounds were identified using ultraperformance liquid chromatography, linked to high resolution electrospray ionisation mass spectrometry and tandem mass spectrometry.<br><br>RESULTS: Cell-free supernatants of X. khoisanae SB10 were heat stable and active against Bacillus subtilis subsp. subtilis, Escherichia coli and Candida albicans. Five lysine-rich lipopeptides from the PAX group were identified in HPLC fractions, with PAX1' and PAX7 present in the highest concentrations. Three novel PAX7 peptides with putative enoyl modifications and two linear analogues of PAX1' were also detected. A small antibiotic compound, yellow in colour and λmax of 314 nm, was recovered from the HPLC fractions and identified as xenocoumacin 2. The PAX lipopeptides and xenocoumacin 2 correlated with the genes and gene clusters in the genome of X. khoisanae SB10.<br><br>CONCLUSION: With UPLC-MS and MSe analyses of compounds in the antimicrobial complex of X. khoisanae SB10, a number of PAX peptides and a xenocoumacin were identified. The combination of pure PAX1' peptide with xenocoumacin 2 resulted in high antimicrobial activity. Many of the fractions did, however, contain labile compounds and some fractions were difficult to resolve. It is thus possible that strain SB10 may produce more antimicrobial compounds than reported here, as suggested by the APE Ec biosynthetic complex. Further research is required to develop these broad-spectrum antimicrobial compounds into drugs that may be used in the fight against microbial infections.},
}
@article {pmid31195952,
year = {2019},
author = {Ikram, M and Ali, N and Jan, G and Guljan, F and Khan, N},
title = {Endophytic fungal diversity and their interaction with plants for agriculture sustainability under stressful condition.},
journal = {Recent patents on food, nutrition &amp; agriculture},
volume = {},
number = {},
pages = {},
doi = {10.2174/2212798410666190612130139},
pmid = {31195952},
issn = {1876-1429},
abstract = {Endophytic fungi or endophytes as fascinating group of organism that colonize widely the healthy internal tissues of living plants, and do not cause any symptoms of disease in the host cells. Several decades of study and research have rustled the co-existing endophytes with their host plants, which can significantly influence the formation of metabolic products in plants, its ability to produce new interesting bioactive compound, which are of pharmaceutical, industrial and agricultural importance. The analytical results indicate that the endophytic fungi can confer profound impacts on plant communities by enhancing their growth, increasing their fitness, strengthening their tolerances to abiotic and biotic stresses, enhance defense mechanism and promoting their accumulation of secondary metabolites that provide immunity to the victims. This review focused on the biodiversity and biological roles of endophytic fungi in association with their host plants through reviewing of published research data obtained from the last 30 years.},
}
@article {pmid31195052,
year = {2019},
author = {Lee, J and Kim, CH and Jang, HA and Kim, JK and Kotaki, T and Shinoda, T and Shinada, T and Yoo, JW and Lee, BL},
title = {Burkholderia gut symbiont modulates titer of specific juvenile hormone in the bean bug Riptortus pedestris.},
journal = {Developmental and comparative immunology},
volume = {99},
number = {},
pages = {103399},
doi = {10.1016/j.dci.2019.103399},
pmid = {31195052},
issn = {1879-0089},
abstract = {Recent studies have provided molecular evidence that gut symbiotic bacteria modulate host insect development, fitness and reproduction. However, the molecular mechanisms through which gut symbionts regulate these aspects of host physiology remain elusive. To address these questions, we prepared two different Riptortus-Burkholderia insect models, Burkholderia gut symbiont-colonized (Sym) Riptortus pedestris insects and gut symbiont-noncolonized (Apo) insects. Upon LC-MS analyses, juvenile hormone III skipped bisepoxide (JHSB3) was newly identified from Riptortus Apo- and Sym-female and male adults' insect hemolymph and JHSB3 titer in the Apo- and Sym-female insects were measured because JH is important for regulating reproduction in adult insects. The JHSB3 titer in the Sym-females were consistently higher compared to those of Apo-females. Since previous studies reported that Riptortus hexamerin-α and vitellogenin proteins were upregulated by the topical abdominal application of a JH-analog, chemically synthesized JHSB3 was administered to Apo-females. As expected, the hexamerin-α and vitellogenin proteins were dramatically increased in the hemolymph of JHSB3-treated Apo-females, resulting in increased egg production compared to that in Sym-females. Taken together, these results demonstrate that colonization of Burkholderia gut symbiont in the host insect stimulates biosynthesis of the heteroptera-specific JHSB3, leading to larger number of eggs produced and enhanced fitness in Riptortus host insects.},
}
@article {pmid31194818,
year = {2019},
author = {Jung, M and Lee, DH},
title = {Abundance and diversity of gut-symbiotic bacteria, the genus Burkholderia in overwintering Riptortus pedestris (Hemiptera: Alydidae) populations and soil in South Korea.},
journal = {PloS one},
volume = {14},
number = {6},
pages = {e0218240},
doi = {10.1371/journal.pone.0218240},
pmid = {31194818},
issn = {1932-6203},
abstract = {Riptortus pedestris is a major agricultural pest on leguminous plants in South Korea and Japan. Recent studies have revealed that R. pedestris can form beneficial symbiosis with bacteria belonging to genus Burkholderia acquired from soil newly for every generation. Although their physiological interactions are relatively well-understood, infection rate and abundance of the Burkholderia in overwintering natural populations of R. pedestris remain unknown. Therefore, the objective of this study was to characterize Burkholderia infection ratio and clade composition of overwintering R. pedestris populations as well as prevalence and diversity of the genus Burkholderia in soil by conducting a two-year field survey. From the field survey, we found 29 overwintering R. pedestris adults in forested areas nearby soybean fields. Diagnostic PCR analysis revealed that overall infection rate of the symbiotic Burkholderia was 93.1% from overwintering adults. Among the Burkholderia-infected R. pedestris, 70.4% of individuals harbored unclassified Burkholderia clades whereas 22.2% and 7.4% of R. pedestris harbor stinkbug-associated beneficial and environmental (SBE) group and Burkholderia cepacia and complex (BCC), respectively. All R. pedestris were infected with a single clade of Burkholderia. In soil, 56.2% of soil samples were Burkholderia positive, and unlike R. pedestris, multiple Burkholderia clades were detected from 62.2% of those samples. Clade composition of the genus Burkholderia in the samples with the bacteria was 91.1%, 60.0%, 31.1% and 8.8% for plant-associated beneficial and environment (PBE), BCC, SBE and unclassified clade, respectively.},
}
@article {pmid31192354,
year = {2019},
author = {Liu, Z and Chen, W and Jiao, S and Wang, X and Fan, M and Wang, E and Wei, G},
title = {New Insight into the Evolution of Symbiotic Genes in Black Locust-Associated Rhizobia.},
journal = {Genome biology and evolution},
volume = {11},
number = {7},
pages = {1736-1750},
doi = {10.1093/gbe/evz116},
pmid = {31192354},
issn = {1759-6653},
abstract = {Nitrogen fixation in legumes occurs via symbiosis with rhizobia. This process involves packages of symbiotic genes on mobile genetic elements that are readily transferred within or between rhizobial species, furnishing the recipient with the ability to interact with plant hosts. However, it remains elusive whether plant host migration has played a role in shaping the current distribution of genetic variation in symbiotic genes. Herein, we examined the genetic structure and phylogeographic pattern of symbiotic genes in 286 symbiotic strains of Mesorhizobium nodulating black locust (Robinia pseudoacacia), a cross-continental invasive legume species that is native to North America. We conducted detailed phylogeographic analysis and approximate Bayesian computation to unravel the complex demographic history of five key symbiotic genes. The sequencing results indicate an origin of symbiotic genes in Germany rather than North America. Our findings provide strong evidence of prehistoric lineage splitting and spatial expansion events resulting in multiple radiations of descendent clones from founding sequence types worldwide. Estimates of the timescale of divergence in North American and Chinese subclades suggest that black locust-specific symbiotic genes have been present in these continent many thousands of years before recent migration of plant host. Although numerous crop plants, including legumes, have found their centers of origin as centers of evolution and diversity, the number of legume-specific symbiotic genes with a known geographic origin is limited. This work sheds light on the coevolution of legumes and rhizobia.},
}
@article {pmid31191571,
year = {2019},
author = {Defrenne, CE and Philpott, TJ and Guichon, SHA and Roach, WJ and Pickles, BJ and Simard, SW},
title = {Shifts in Ectomycorrhizal Fungal Communities and Exploration Types Relate to the Environment and Fine-Root Traits Across Interior Douglas-Fir Forests of Western Canada.},
journal = {Frontiers in plant science},
volume = {10},
number = {},
pages = {643},
doi = {10.3389/fpls.2019.00643},
pmid = {31191571},
issn = {1664-462X},
abstract = {Large-scale studies that examine the responses of ectomycorrhizal fungi across biogeographic gradients are necessary to assess their role in mediating current and predicted future alterations in forest ecosystem processes. We assessed the extent of environmental filtering on interior Douglas-fir (Pseudotsuga menziesii var. glauca (Beissn.) Franco) ectomycorrhizal fungal communities across regional gradients in precipitation, temperature, and soil fertility in interior Douglas-fir dominated forests of western Canada. We also examined relationships between fine-root traits and mycorrhizal fungal exploration types by combining root and fungal trait measurements with next-generation sequencing. Temperature, precipitation, and soil C:N ratio affected fungal community dissimilarity and exploration type abundance but had no effect on α-diversity. Fungi with rhizomorphs (e.g., Piloderma sp.) or proteolytic abilities (e.g., Cortinarius sp.) dominated communities in warmer and less fertile environments. Ascomycetes (e.g., Cenococcum geophilum) or shorter distance explorers, which potentially cost the plant less C, were favored in colder/drier climates where soils were richer in total nitrogen. Environmental filtering of ectomycorrhizal fungal communities is potentially related to co-evolutionary history between Douglas-fir populations and fungal symbionts, suggesting success of interior Douglas-fir as climate changes may be dependent on maintaining strong associations with local communities of mycorrhizal fungi. No evidence for a link between root and fungal resource foraging strategies was found at the regional scale. This lack of evidence further supports the need for a mycorrhizal symbiosis framework that is independent of root trait frameworks, to aid in understanding belowground plant uptake strategies across environments.},
}
@article {pmid31191510,
year = {2019},
author = {Habineza, P and Muhammad, A and Ji, T and Xiao, R and Yin, X and Hou, Y and Shi, Z},
title = {The Promoting Effect of Gut Microbiota on Growth and Development of Red Palm Weevil, Rhynchophorus ferrugineus (Olivier) (Coleoptera: Dryophthoridae) by Modulating Its Nutritional Metabolism.},
journal = {Frontiers in microbiology},
volume = {10},
number = {},
pages = {1212},
doi = {10.3389/fmicb.2019.01212},
pmid = {31191510},
issn = {1664-302X},
abstract = {Red palm weevil (RPW), Rhynchophorus ferrugineus Olivier, is a destructive pest for palm trees worldwide. Recent studies have shown that RPW gut is colonized by microbes and alterations in gut microbiota can significantly modify its hemolymph nutrition content. However, the exact effects of gut microbiota on RPW phenotype and the underlying mechanisms remain elusive. Here germ-free (GF) RPW larvae were generated from dechorionated eggs which were reared on sterilized artificial food under axenic conditions. Compared with controls, the larval development of GF RPW individuals was markedly depressed and their body mass was reduced as well. Furthermore, the content of hemolymph protein, glucose and triglyceride were dropped significantly in GF RPW larvae. Interestingly, introducing gut microbiota into GF individuals could significantly increase the levels of the three nutrition indices. Additionally, it has also been demonstrated that RPW larvae monoassociated with Lactococcus lactis exhibited the same level of protein content with the CR (conventionally reared) insects while feeding Enterobacter cloacae to GF larvae increased their hemolymph triglyceride and glucose content markedly. Consequently, our findings suggest that gut microbiota profoundly affect the development of this pest by regulating its nutrition metabolism and different gut bacterial species show distinct impact on host physiology. Taken together, the establishment of GF and gnotobiotic RPW larvae will advance the elucidation of molecular mechanisms behind the interactions between RPW and its gut microbiota.},
}
@article {pmid31190278,
year = {2019},
author = {Lee, SJ and Morse, D and Hijri, M},
title = {Holobiont chronobiology: mycorrhiza may be a key to linking aboveground and underground rhythms.},
journal = {Mycorrhiza},
volume = {},
number = {},
pages = {},
doi = {10.1007/s00572-019-00903-4},
pmid = {31190278},
issn = {1432-1890},
support = {RGPIN-2018-04178//Natural Sciences and Engineering Research Council of Canada/ ; },
abstract = {Circadian clocks are nearly ubiquitous timing mechanisms that can orchestrate rhythmic behavior and gene expression in a wide range of organisms. Clock mechanisms are becoming well understood in fungal, animal, and plant model systems, yet many of these organisms are surrounded by a complex and diverse microbiota which should be taken into account when examining their biology. Of particular interest are the symbiotic relationships between organisms that have coevolved over time, forming a unit called a holobiont. Several studies have now shown linkages between the circadian rhythms of symbiotic partners. Interrelated regulation of holobiont circadian rhythms seems thus important to coordinate shifts in activity over the day for all the partners. Therefore, we suggest that the classical view of &quot;chronobiological individuals&quot; should include &quot;a holobiont&quot; rather than an organism. Unfortunately, mechanisms that may regulate interspecies temporal acclimation and the evolution of the circadian clock in holobionts are far from being understood. For the plant holobiont, our understanding is particularly limited. In this case, the holobiont encompasses two different ecosystems, one above and the other below the ground, with the two potentially receiving timing information from different synchronizing signals (Zeitgebers). The arbuscular mycorrhizal (AM) symbiosis, formed by plant roots and fungi, is one of the oldest and most widespread associations between organisms. By mediating the nutritional flux between the plant and the many microbes in the soil, AM symbiosis constitutes the backbone of the plant holobiont. Even though the importance of the AM symbiosis has been well recognized in agricultural and environmental sciences, its circadian chronobiology remains almost completely unknown. We have begun to study the circadian clock of arbuscular mycorrhizal fungi, and we compile and here discuss the available information on the subject. We propose that analyzing the interrelated temporal organization of the AM symbiosis and determining its underlying mechanisms will advance our understanding of the role and coordination of circadian clocks in holobionts in general.},
}
@article {pmid31189014,
year = {2019},
author = {Guo, X and Zhao, Z and Mar, SS and Zhang, D and Saunders, RMK},
title = {A symbiotic balancing act: arbuscular mycorrhizal specificity and specialist fungus gnat pollination in the mycoheterotrophic genus Thismia (Thismiaceae).},
journal = {Annals of botany},
volume = {},
number = {},
pages = {},
doi = {10.1093/aob/mcz087},
pmid = {31189014},
issn = {1095-8290},
abstract = {BACKGROUND AND AIMS: Mycorrhizal associations in mycoheterotrophic plants are generally more specialized than in autotrophs. Mycoheterotrophs typically bear small, inconspicuous flowers that often self-pollinate to maximize seed set, although some have structurally complex flowers indicative of xenogamy. A trade-off has previously been proposed between specialization in these above- and below-ground symbioses, although empirical data are lacking.<br><br>METHODS: We used next-generation DNA sequencing to compare the mycorrhizal communities from the roots of a mycoheterotrophic species, Thismia tentaculata (Thismiaceae), and its neighbouring autotrophs. We furthermore conducted detailed assessments of floral phenology and pollination ecology, and performed artificial pollination experiments to determine the breeding system.<br><br>KEY RESULTS: Thismia tentaculata maintains a symbiotic association with a single arbuscular mycorrhizal Rhizophagus species. The flowers are pollinated by a single species of fungus gnats (Corynoptera, Sciaridae), which are attracted by the yellow pigments and are temporarily restrained within the perianth chamber before departing via apertures between the anthers. The plants are self-compatible but predominantly xenogamous.<br><br>CONCLUSIONS: Our findings demonstrate that T. tentaculata maintains highly specialized associations with pollinators and mycorrhizal fungi, both of which are widely distributed. We suggest that specialization in multiple symbiotic interactions is possible in mycoheterotrophs if redundant selective pressures are not exerted to further restrict an already constrained suite of life-history traits.},
}
@article {pmid31186513,
year = {2019},
author = {Gabay, Y and Parkinson, JE and Wilkinson, SP and Weis, VM and Davy, SK},
title = {Inter-partner specificity limits the acquisition of thermotolerant symbionts in a model cnidarian-dinoflagellate symbiosis.},
journal = {The ISME journal},
volume = {},
number = {},
pages = {},
doi = {10.1038/s41396-019-0429-5},
pmid = {31186513},
issn = {1751-7370},
abstract = {The ability of corals and other cnidarians to survive climate change depends partly on the composition of their endosymbiont communities. The dinoflagellate family Symbiodiniaceae is genetically and physiologically diverse, and one proposed mechanism for cnidarians to acclimate to rising temperatures is to acquire more thermally tolerant symbionts. However, cnidarian-dinoflagellate associations vary in their degree of specificity, which may limit their capacity to alter symbiont communities. Here, we inoculated symbiont-free polyps of the sea anemone Exaiptasia pallida (commonly referred to as 'Aiptasia'), a model system for the cnidarian-dinoflagellate symbiosis, with simultaneous or sequential mixtures of thermally tolerant and thermally sensitive species of Symbiodiniaceae. We then monitored symbiont success (relative proportional abundance) at normal and elevated temperatures across two to four weeks. All anemones showed signs of bleaching at high temperature. During simultaneous inoculations, the native, thermally sensitive Breviolum minutum colonized polyps most successfully regardless of temperature when paired against the non-native but more thermally tolerant Symbiodinium microadriaticum or Durusdinium trenchii. Furthermore, anemones initially colonized with B. minutum and subsequently exposed to S. microadriaticum failed to acquire the new symbiont. These results highlight how partner specificity may place strong limitations on the ability of certain cnidarians to acquire more thermally tolerant symbionts, and hence their adaptive potential under climate change.},
}
@article {pmid31186318,
year = {2019},
author = {Chrostek, E and Gerth, M},
title = {Is Anopheles gambiae a Natural Host of Wolbachia?.},
journal = {mBio},
volume = {10},
number = {3},
pages = {},
doi = {10.1128/mBio.00784-19},
pmid = {31186318},
issn = {2150-7511},
abstract = {Wolbachia (Alphaproteobacteria, Rickettsiales) is an intraovarially transmitted symbiont of insects able to exert striking phenotypes, including reproductive manipulations and pathogen blocking. These phenotypes make Wolbachia a promising tool to combat mosquito-borne diseases. Although Wolbachia is present in the majority of terrestrial arthropods, including many disease vectors, it was considered absent from Anopheles gambiae mosquitos, the main vectors of malaria in sub-Saharan Africa. In 2014, Wolbachia sequences were detected in A. gambiae samples collected in Burkina Faso. Subsequently, similar evidence came from collections all over Africa, revealing a high Wolbachia 16S rRNA sequence diversity, low abundance, and a lack of congruence between host and symbiont phylogenies. Here, we reanalyze and discuss recent evidence on the presence of Wolbachia sequences in A. gambiae. We find that although detected at increasing frequencies, the unusual properties of these Wolbachia sequences render them insufficient to diagnose natural infections in A. gambiae Future studies should focus on uncovering the origin of Wolbachia sequence variants in Anopheles and seeking sequence-independent evidence for this new symbiosis. Understanding the ecology of Anopheles mosquitos and their interactions with Wolbachia will be key in designing successful, integrative approaches to limit malaria spread. Although the prospect of using Wolbachia to fight malaria is intriguing, the newly discovered strains do not bring it closer to realization.IMPORTANCEAnopheles gambiae mosquitos are the main vectors of malaria, threatening around half of the world's population. The bacterial symbiont Wolbachia can interfere with disease transmission by other important insect vectors, but until recently, it was thought to be absent from natural A. gambiae populations. Here, we critically analyze the genomic, metagenomic, PCR, imaging, and phenotypic data presented in support of the presence of natural Wolbachia infections in A. gambiae We find that they are insufficient to diagnose Wolbachia infections and argue for the need of obtaining robust data confirming basic Wolbachia characteristics in this system. Determining the Wolbachia infection status of Anopheles is critical due to its potential to influence Anopheles population structure and Plasmodium transmission.},
}
@article {pmid31186308,
year = {2019},
author = {Septer, AN},
title = {The Vibrio-Squid Symbiosis as a Model for Studying Interbacterial Competition.},
journal = {mSystems},
volume = {4},
number = {3},
pages = {},
doi = {10.1128/mSystems.00108-19},
pmid = {31186308},
issn = {2379-5077},
abstract = {The symbiosis between Euprymna scolopes squid and its bioluminescent bacterial symbiont, Vibrio fischeri, is a valuable model system to study a natural, coevolved host-microbe association. Over the past 30 years, researchers have developed and optimized many experimental methods to study both partners in isolation and during symbiosis. These powerful tools, along with a strong foundational knowledge about the system, position the Vibrio-squid symbiosis at the forefront of host-microbe interactions because this system is uniquely suited to investigation of symbiosis from both host and bacterial perspectives. Moreover, the ability to isolate and characterize different strains of V. fischeri has revealed exciting new insights about how different genotypes evolve to compete for a host niche, including deploying interbacterial weapons early during host colonization. This Perspective explores how interbacterial warfare influences the diversity and spatial structure of the symbiotic population, as well as the possible effects that intraspecific competition might have on the host.},
}
@article {pmid31184576,
year = {2019},
author = {Gomes, DF and Tullio, LD and Del Cerro, P and Nakatani, AS and Rolla-Santos, AAP and Gil-Serrano, A and Megías, M and Ollero, FJ and Hungria, M},
title = {Regulation of hsnT, nodF and nodE genes in Rhizobium tropici CIAT 899 and their roles in the synthesis of Nod factors and in the symbiosis.},
journal = {Microbiology (Reading, England)},
volume = {165},
number = {9},
pages = {990-1000},
doi = {10.1099/mic.0.000824},
pmid = {31184576},
issn = {1465-2080},
abstract = {Rhizobium tropici strain CIAT 899 possesses outstanding agronomic properties as it displays tolerance to environmental stresses, a broad host range and high effectiveness in fixing nitrogen with the common bean (Phaseolus vulgaris L.); in addition, it carries intriguing features such as five copies of the regulatory nodD gene, and the capacity to synthesize a variety of nodulation factors (NFs), even in a flavonoid-independent manner, when submitted to abiotic stresses. However, the roles of several nod genes of the repertoire of CIAT 899 remain to be determined. In this study, we obtained mutants for the hsnT, nodF and nodE genes of CIAT 899 and investigated their expression, NF structures and symbiotic properties. Either in the presence of the flavonoid apigenin, or of salt the expression of hsnT, nodF and nodE in wild-type CIAT 899 was highly up-regulated in comparison to the mutants of all five copies of nodD, indicating the roles that regulatory nodD genes play in the activation of hsnT, nodF and nodE; however, NodD1 was recognized as the main inducer. In total, 29 different NF structures were synthesized by wild-type CIAT 899 induced by apigenin, and 36 when induced by salt, being drastically reduced by mutations in hsnT, nodF and nodE, especially under osmotic stress, with specific changes related to each gene, indicating that the three genes participate in the synthesis of NFs. Mutations in hsnT, nodF and nodE affected differently symbiotic performance (nodule number and shoot dry weight), according to the host plant. Our results indicate that the expression of hsnT, nodF and nodE genes of CIAT 899 is mediated by nodD genes, and although these three genes do not belong to the main set of genes controlling nodulation, they contribute to the synthesis of NFs that will impact symbiotic performance and host specificity.},
}
@article {pmid31182796,
year = {2019},
author = {Gruber-Vodicka, HR and Leisch, N and Kleiner, M and Hinzke, T and Liebeke, M and McFall-Ngai, M and Hadfield, MG and Dubilier, N},
title = {Two intracellular and cell type-specific bacterial symbionts in the placozoan Trichoplax H2.},
journal = {Nature microbiology},
volume = {4},
number = {9},
pages = {1465-1474},
doi = {10.1038/s41564-019-0475-9},
pmid = {31182796},
issn = {2058-5276},
abstract = {Placozoa is an enigmatic phylum of simple, microscopic, marine metazoans1,2. Although intracellular bacteria have been found in all members of this phylum, almost nothing is known about their identity, location and interactions with their host3-6. We used metagenomic and metatranscriptomic sequencing of single host individuals, plus metaproteomic and imaging analyses, to show that the placozoan Trichoplax sp. H2 lives in symbiosis with two intracellular bacteria. One symbiont forms an undescribed genus in the Midichloriaceae (Rickettsiales)7,8 and has a genomic repertoire similar to that of rickettsial parasites9,10, but does not seem to express key genes for energy parasitism. Correlative image analyses and three-dimensional electron tomography revealed that this symbiont resides in the rough endoplasmic reticulum of its host's internal fibre cells. The second symbiont belongs to the Margulisbacteria, a phylum without cultured representatives and not known to form intracellular associations11-13. This symbiont lives in the ventral epithelial cells of Trichoplax, probably metabolizes algal lipids digested by its host and has the capacity to supplement the placozoan's nutrition. Our study shows that one of the simplest animals has evolved highly specific and intimate associations with symbiotic, intracellular bacteria and highlights that symbioses can provide access to otherwise elusive microbial dark matter.},
}
@article {pmid31182497,
year = {2019},
author = {Lamouche, F and Chaumeret, A and Guefrachi, I and Barrière, Q and Pierre, O and Guérard, F and Gilard, F and Giraud, E and Dessaux, Y and Gakière, B and Timchenko, T and Kereszt, A and Mergaert, P and Alunni, B},
title = {From Intracellular Bacteria to Differentiated Bacteroids: Transcriptome and Metabolome Analysis in Aeschynomene Nodules Using the Bradyrhizobium sp. Strain ORS285 bclA Mutant.},
journal = {Journal of bacteriology},
volume = {201},
number = {17},
pages = {},
doi = {10.1128/JB.00191-19},
pmid = {31182497},
issn = {1098-5530},
abstract = {Soil bacteria called rhizobia trigger the formation of root nodules on legume plants. The rhizobia infect these symbiotic organs and adopt an intracellular lifestyle within the nodule cells, where they differentiate into nitrogen-fixing bacteroids. Several legume lineages force their symbionts into an extreme cellular differentiation, comprising cell enlargement and genome endoreduplication. The antimicrobial peptide transporter BclA is a major determinant of this process in Bradyrhizobium sp. strain ORS285, a symbiont of Aeschynomene spp. In the absence of BclA, the bacteria proceed until the intracellular infection of nodule cells, but they cannot differentiate into enlarged polyploid and functional bacteroids. Thus, the bclA nodule bacteria constitute an intermediate stage between the free-living soil bacteria and the nitrogen-fixing bacteroids. Metabolomics on whole nodules of Aeschynomene afraspera and Aeschynomene indica infected with the wild type or the bclA mutant revealed 47 metabolites that differentially accumulated concomitantly with bacteroid differentiation. Bacterial transcriptome analysis of these nodules demonstrated that the intracellular settling of the rhizobia in the symbiotic nodule cells is accompanied by a first transcriptome switch involving several hundred upregulated and downregulated genes and a second switch accompanying the bacteroid differentiation, involving fewer genes but ones that are expressed to extremely elevated levels. The transcriptomes further suggested a dynamic role for oxygen and redox regulation of gene expression during nodule formation and a nonsymbiotic function of BclA. Together, our data uncover the metabolic and gene expression changes that accompany the transition from intracellular bacteria into differentiated nitrogen-fixing bacteroids.IMPORTANCE Legume-rhizobium symbiosis is a major ecological process, fueling the biogeochemical nitrogen cycle with reduced nitrogen. It also represents a promising strategy to reduce the use of chemical nitrogen fertilizers in agriculture, thereby improving its sustainability. This interaction leads to the intracellular accommodation of rhizobia within plant cells of symbiotic organs, where they differentiate into nitrogen-fixing bacteroids. In specific legume clades, this differentiation process requires the bacterial transporter BclA to counteract antimicrobial peptides produced by the host. Transcriptome analysis of Bradyrhizobium wild-type and bclA mutant bacteria in culture and in symbiosis with Aeschynomene host plants dissected the bacterial transcriptional response in distinct phases and highlighted functions of the transporter in the free-living stage of the bacterial life cycle.},
}
@article {pmid31182189,
year = {2019},
author = {Strohm, E and Herzner, G and Ruther, J and Kaltenpoth, M and Engl, T},
title = {Nitric oxide radicals are emitted by wasp eggs to kill mold fungi.},
journal = {eLife},
volume = {8},
number = {},
pages = {},
doi = {10.7554/eLife.43718},
pmid = {31182189},
issn = {2050-084X},
abstract = {Detrimental microbes caused the evolution of a great diversity of antimicrobial defenses in plants and animals. Insects developing underground seem particularly threatened. Here we show that the eggs of a solitary digger wasp, the European beewolf Philanthus triangulum, emit large amounts of gaseous nitric oxide (NO⋅) to protect themselves and their provisions, paralyzed honeybees, against mold fungi. We provide evidence that a NO-synthase (NOS) is involved in the generation of the extraordinary concentrations of nitrogen radicals in brood cells (~1500 ppm NO⋅ and its oxidation product NO2⋅). Sequencing of the beewolf NOS gene revealed no conspicuous differences to related species. However, due to alternative splicing, the NOS-mRNA in beewolf eggs lacks an exon near the regulatory domain. This preventive external application of high doses of NO⋅ by wasp eggs represents an evolutionary key innovation that adds a remarkable novel facet to the array of functions of the important biological effector NO⋅.},
}
@article {pmid31181739,
year = {2019},
author = {Hao, Z and Xie, W and Chen, B},
title = {Arbuscular Mycorrhizal Symbiosis Affects Plant Immunity to Viral Infection and Accumulation.},
journal = {Viruses},
volume = {11},
number = {6},
pages = {},
doi = {10.3390/v11060534},
pmid = {31181739},
issn = {1999-4915},
support = {41571250//National Natural Science Foundation of China/ ; 2016YFC0500702//National Key Research and Development Program of China/ ; },
abstract = {Arbuscular mycorrhizal (AM) fungi, as root symbionts of most terrestrial plants, improve plant growth and fitness. In addition to the improved plant nutritional status, the physiological changes that trigger metabolic changes in the root via AM fungi can also increase the host ability to overcome biotic and abiotic stresses. Plant viruses are one of the important limiting factors for the commercial cultivation of various crops. The effect of AM fungi on viral infection is variable, and considerable attention is focused on shoot virus infection. This review provides an overview of the potential of AM fungi as bioprotection agents against viral diseases and emphasizes the complex nature of plant-fungus-virus interactions. Several mechanisms, including modulated plant tolerance, manipulation of induced systemic resistance (ISR), and altered vector pressure are involved in such interactions. We propose that using &quot;omics&quot; tools will provide detailed insights into the complex mechanisms underlying mycorrhizal-mediated plant immunity.},
}
@article {pmid31181676,
year = {2019},
author = {Ho, YS},
title = {Comment to: Qi, Yi, et al. &quot;Bibliometric Analysis of Algal-Bacterial Symbiosis in Wastewater Treatment&quot;, Int. J. Environ. Res. Public Health 2019, 16, 1077.},
journal = {International journal of environmental research and public health},
volume = {16},
number = {11},
pages = {},
doi = {10.3390/ijerph16112034},
pmid = {31181676},
issn = {1660-4601},
mesh = {Bibliometrics ; *Public Health ; Symbiosis ; *Waste Water ; },
abstract = {Qi et al. recently published an article in the journal, entitled &quot;Bibliometric Analysis of Algal-Bacterial Symbiosis in Wastewater Treatment&quot; [...].},
}
@article {pmid31179246,
year = {2019},
author = {Thapa, V and Roossinck, MJ},
title = {Determinants of Coinfection in the Mycoviruses.},
journal = {Frontiers in cellular and infection microbiology},
volume = {9},
number = {},
pages = {169},
doi = {10.3389/fcimb.2019.00169},
pmid = {31179246},
issn = {2235-2988},
}
@article {pmid31178314,
year = {2019},
author = {Whiteside, MD and Werner, GDA and Caldas, VEA and Van't Padje, A and Dupin, SE and Elbers, B and Bakker, M and Wyatt, GAK and Klein, M and Hink, MA and Postma, M and Vaitla, B and Noë, R and Shimizu, TS and West, SA and Kiers, ET},
title = {Mycorrhizal Fungi Respond to Resource Inequality by Moving Phosphorus from Rich to Poor Patches across Networks.},
journal = {Current biology : CB},
volume = {29},
number = {12},
pages = {2043-2050.e8},
doi = {10.1016/j.cub.2019.04.061},
pmid = {31178314},
issn = {1879-0445},
abstract = {The world's ecosystems are characterized by an unequal distribution of resources [1]. Trade partnerships between organisms of different species-mutualisms-can help individuals cope with such resource inequality [2-4]. Trade allows individuals to exchange commodities they can provide at low cost for resources that are otherwise impossible or more difficult to access [5, 6]. However, as resources become increasingly patchy in time or space, it is unknown how organisms alter their trading strategies [7, 8]. Here, we show how a symbiotic fungus mediates trade with a host root in response to different levels of resource inequality across its network. We developed a quantum-dot-tracking technique to quantify phosphorus-trading strategies of arbuscular mycorrhizal fungi simultaneously exposed to rich and poor resource patches. By following fluorescent nanoparticles of different colors across fungal networks, we determined where phosphorus was hoarded, relocated, and transferred to plant hosts. We found that increasing exposure to inequality stimulated trade. Fungi responded to high resource variation by (1) increasing the total amount of phosphorus distributed to host roots, (2) decreasing allocation to storage, and (3) differentially moving resources within the network from rich to poor patches. Using single-particle tracking and high-resolution video, we show how dynamic resource movement may help the fungus capitalize on value differences across the trade network, physically moving resources to areas of high demand to gain better returns. Such translocation strategies can help symbiotic organisms cope with exposure to resource inequality.},
}
@article {pmid31178238,
year = {2019},
author = {Spagnoletti, FN and Chiocchio, VM},
title = {Tolerance of dark septate endophytic fungi (DSE) to agrochemicals in vitro.},
journal = {Revista Argentina de microbiologia},
volume = {},
number = {},
pages = {},
doi = {10.1016/j.ram.2019.02.003},
pmid = {31178238},
issn = {0325-7541},
abstract = {Dark septate endophytes (DSE) are a heterogeneous group of fungi, mostly belonging to the Phylum Ascomycota, that are involved in a mutualistic symbiosis with plant roots. The aim of this study is to evaluate the behavior of two strains of DSE isolated from wheat roots of two cropping areas in the province of Buenos Aires, Argentina, against some agrochemicals. Of all the isolates obtained, two strains were identified as Alternaria alternata and Cochliobolus sp. These DSE were found to be tolerant to glyphosate, carbendazim and cypermethrin when evaluated at the recommended agronomic dose (AD), 2 AD and, in some cases, 10 AD. This work contributes to the study of the biology of this group of fungi and their tolerance in the presence of xenobiotics widely used in agriculture.},
}
@article {pmid31177643,
year = {2019},
author = {Wang, S and Lu, T and Xue, Q and Xu, K and Cheng, G},
title = {Antioxidation and symbiotic nitrogen fixation function of prxA gene in Mesorhizobium huakuii.},
journal = {MicrobiologyOpen},
volume = {},
number = {},
pages = {e889},
doi = {10.1002/mbo3.889},
pmid = {31177643},
issn = {2045-8827},
support = {31772399//National Natural Science Foundation of China/ ; //Fundamental Research Funds for the Central Universities/ ; CZY18022//South-Central University for Nationalities/ ; },
abstract = {Peroxiredoxins (Prxs) play an essential role in the antioxidant activity and symbiotic capacity of Mesorhizobium huakuii. A mutation in the M. huakuii prxA gene (encoding a Prx5-like peroxiredoxin) was generated by homologous recombination. The mutation of prxA did not affect M. huakuii growth, but the strain displayed decreased antioxidative capacity under organic cumene hydroperoxide (CUOOH) conditions. The higher resistance of the prxA mutant strain compared with the wild-type strain to more than 1 mmol/L H2 O2 was associated with a significantly higher level of glutathione reductase activity and a significantly lower level of intracellular hydrogen peroxide content. Real-time quantitative PCR showed that under 1 mmol/L H2 O2 conditions, expression of the stress-responsive genes katG and katE was significantly upregulated in the prxA mutant. Although the prxA mutant can form nodules, the symbiotic ability was severely impaired, which led to an abnormal nodulation phenotype coupled to a 53.25% reduction in nitrogen fixation capacity. This phenotype was linked to an absence of bacteroid differentiation and deregulation of the transcription of the symbiotic genes nifH, nifD, and fdxN. Expression of the prxA gene was induced during symbiosis. Thus, the PrxA protein is essential for antioxidant capacity and symbiotic nitrogen fixation, playing independent roles in bacterial differentiation and cellular antioxidative systems.},
}
@article {pmid31176943,
year = {2019},
author = {Rempel, A and de Souza Sossella, F and Margarites, AC and Astolfi, AL and Steinmetz, RLR and Kunz, A and Treichel, H and Colla, LM},
title = {Bioethanol from Spirulina platensis biomass and the use of residuals to produce biomethane: An energy efficient approach.},
journal = {Bioresource technology},
volume = {288},
number = {},
pages = {121588},
doi = {10.1016/j.biortech.2019.121588},
pmid = {31176943},
issn = {1873-2976},
abstract = {This study aimed to produce bioethanol using Spirulina platensis biomass and the use of saccharification and fermentation wastes of bioethanol production to produce biomethane. The potential for energy generation in each technological route was quantified. Both, the enzymatic hydrolysis of the microalgae polysaccharides and the fermentation process, presented efficiencies above 80%. The fermentation of the hydrolyzate into ethanol was possible without the addition of synthetic nutrients to the must. The direct conversion of Spirulina biomass to biomethane had an energy potential of 16,770 kJ.kg-1, while bioethanol production from the hydrolysed biomass presented 4,664 kJ.kg-1. However, the sum of the energy potential obtained by producing bioethanol followed by the production of biomethane with the saccharification and fermentation residues was 13,945 kJ.kg-1. Despite this, the same raw material was able to produce both biofuels, demonstrating that Spirulina microalgae is a promising alternative to contribute in the field of renewable energies.},
}
@article {pmid31176662,
year = {2019},
author = {Olivieri, E and Epis, S and Castelli, M and Varotto Boccazzi, I and Romeo, C and Desirò, A and Bazzocchi, C and Bandi, C and Sassera, D},
title = {Tissue tropism and metabolic pathways of Midichloria mitochondrii suggest tissue-specific functions in the symbiosis with Ixodes ricinus.},
journal = {Ticks and tick-borne diseases},
volume = {10},
number = {5},
pages = {1070-1077},
doi = {10.1016/j.ttbdis.2019.05.019},
pmid = {31176662},
issn = {1877-9603},
abstract = {A wide range of arthropod species harbour bacterial endosymbionts in various tissues, many of them playing important roles in the fitness and biology of their hosts. In several cases, many different symbionts have been reported to coexist simultaneously within the same host and synergistic or antagonistic interactions can occur between them. While the associations with endosymbiotic bacteria have been widely studied in many insect species, in ticks such interactions are less investigated. The females and immatures of Ixodes ricinus (Ixodidae), the most common hard tick in Europe, harbour the intracellular endosymbiont &quot;Candidatus Midichloria mitochondrii&quot; with a prevalence up to 100%, suggesting a mutualistic relationship. Considering that the tissue distribution of a symbiont might be indicative of its functional role in the physiology of the host, we investigated M. mitochondrii specific localization pattern and the corresponding abundance in selected organs of I. ricinus females. We paired these experiments with in silico analysis of the metabolic pathways of M. mitochondrii, inferred from the available genome sequence, and additionally compared the presence of these pathways in seven other symbionts commonly harboured by ticks to try to obtain a comparative understanding of their biological effects on the tick hosts. M. mitochondrii was found to be abundant in ovaries and tracheae of unfed I. ricinus, and in ovaries, Malpighian tubules and salivary glands of semi-engorged females. These results, together with the in silico metabolic reconstruction allow to hypothesize that the bacterium could play multiple tissue-specific roles in the host, both enhancing the host fitness (supplying essential nutrients, enhancing the reproductive fitness, helping in the anti-oxidative defence, in the energy production and in the maintenance of homeostasis and water balance) and/or for ensuring its presence in the host population (nutrients acquisition, vertical and horizontal transmission). The ability of M. mitochondrii to colonize different tissues allows to speculate that distinctive sub-populations may display different specializations in accordance with tissue tropism. Our hypotheses should be corroborated with future nutritional and physiological experiments for a better understanding of the mechanisms underlying this symbiotic interaction.},
}
@article {pmid31174466,
year = {2019},
author = {Baião, GC and Schneider, DI and Miller, WJ and Klasson, L},
title = {The effect of Wolbachia on gene expression in Drosophila paulistorum and its implications for symbiont-induced host speciation.},
journal = {BMC genomics},
volume = {20},
number = {1},
pages = {465},
doi = {10.1186/s12864-019-5816-9},
pmid = {31174466},
issn = {1471-2164},
support = {2014-4353//Vetenskapsrådet/ ; P28255-B22//Austrian Science Fund/ ; },
abstract = {BACKGROUND: The Neotropical fruit fly Drosophila paulistorum (Diptera: Drosophilidae) is a species complex in statu nascendi comprising six reproductively isolated semispecies, each harboring mutualistic Wolbachia strains. Although wild type flies of each semispecies are isolated from the others by both pre- and postmating incompatibilities, mating between semispecies and successful offspring development can be achieved once flies are treated with antibiotics to reduce Wolbachia titer. Here we use RNA-seq to study the impact of Wolbachia on D. paulistorum and investigate the hypothesis that the symbiont may play a role in host speciation. For that goal, we analyze samples of heads and abdomens of both sexes of the Amazonian, Centro American and Orinocan semispecies of D. paulistorum.<br><br>RESULTS: We identify between 175 and 1192 differentially expressed genes associated with a variety of biological processes that respond either globally or according to tissue, sex or condition in the three semispecies. Some of the functions associated with differentially expressed genes are known to be affected by Wolbachia in other species, such as metabolism and immunity, whereas others represent putative novel phenotypes involving muscular functions, pheromone signaling, and visual perception.<br><br>CONCLUSIONS: Our results show that Wolbachia affect a large number of biological functions in D. paulistorum, particularly when present in high titer. We suggest that the significant metabolic impact of the infection on the host may cause several of the other putative and observed phenotypes. We also speculate that the observed differential expression of genes associated with chemical communication and reproduction may be associated with the emergence of pre- and postmating barriers between semispecies, which supports a role for Wolbachia in the speciation of D. paulistorum.},
}
@article {pmid31172251,
year = {2019},
author = {Taboada, H and Dunn, MF and Meneses, N and Vargas-Lagunas, C and Buchs, N and Andrade-Domínguez, A and Encarnación, S},
title = {Qualitative changes in proteins contained in outer membrane vesicles produced by Rhizobium etli grown in the presence of the nod gene inducer naringenin.},
journal = {Archives of microbiology},
volume = {},
number = {},
pages = {},
doi = {10.1007/s00203-019-01682-4},
pmid = {31172251},
issn = {1432-072X},
support = {220790//CONACYT/ ; IN213216//DGAPA-PAPIIT-UNAM/ ; IN207519//DGAPA-PAPIIT-UNAM/ ; },
abstract = {In this work, we compared the proteomic profiles of outer membrane vesicles (OMVs) isolated from Rhizobium etli CE3 grown in minimal medium (MM) with and without exogenous naringenin. One-hundred and seven proteins were present only in OMVs from naringenin-containing cultures (N-OMVs), 57 proteins were unique to OMVs from control cultures lacking naringenin (C-OMVs) and 303 proteins were present in OMVs from both culture conditions (S-OMVs). Although we found no absolute predominance of specific types of proteins in the N-, C- or S-OMV classes, there were categories of proteins that were significantly less or more common in the different OMV categories. Proteins for energy production, translation and membrane and cell wall biogenesis were overrepresented in C-OMVs relative to N-OMVs. Proteins for carbohydrate metabolism and transport and those classified as either general function prediction only, function unknown, or without functional prediction were more common in N-OMVs than C-OMVs. This indicates that naringenin increased the proportion of these proteins in the OMVs, although NodD binding sites were only slightly more common in the promoters of genes for proteins found in the N-OMVs. In addition, OMVs from naringenin-containing cultures contained nodulation factor.},
}
@article {pmid31170026,
year = {2019},
author = {Belin, BJ and Tookmanian, EM and de Anda, J and Wong, GCL and Newman, DK},
title = {Extended Hopanoid Loss Reduces Bacterial Motility and Surface Attachment and Leads to Heterogeneity in Root Nodule Growth Kinetics in a Bradyrhizobium-Aeschynomene Symbiosis.},
journal = {Molecular plant-microbe interactions : MPMI},
volume = {},
number = {},
pages = {MPMI04190111R},
doi = {10.1094/MPMI-04-19-0111-R},
pmid = {31170026},
issn = {0894-0282},
abstract = {Hopanoids are steroid-like bacterial lipids that enhance membrane rigidity and promote bacterial growth under diverse stresses. Hopanoid biosynthesis genes are conserved in nitrogen-fixing plant symbionts, and we previously found that the extended (C35) class of hopanoids in Bradyrhizobium diazoefficiens are required for efficient symbiotic nitrogen fixation in the tropical legume host Aeschynomene afraspera. Here, we demonstrate that the nitrogen-fixation defect conferred by extended hopanoid loss can be fully explained by a reduction in root nodule sizes rather than per-bacteroid nitrogen-fixation levels. Using a single-nodule tracking approach to quantify A. afraspera nodule development, we provide a quantitative model of root nodule development in this host, uncovering both the baseline growth parameters for wild-type nodules and a surprising heterogeneity of extended hopanoid mutant developmental phenotypes. These phenotypes include a delay in root nodule initiation and the presence of a subpopulation of nodules with slow growth rates and low final volumes, which are correlated with reduced motility and surface attachment in vitro and lower bacteroid densities in planta, respectively. This work provides a quantitative reference point for understanding the phenotypic diversity of ineffective symbionts in A. afraspera and identifies specific developmental stages affected by extended hopanoid loss for future mechanistic work.},
}
@article {pmid31167992,
year = {2019},
author = {Ohbayashi, T and Itoh, H and Lachat, J and Kikuchi, Y and Mergaert, P},
title = {Burkholderia Gut Symbionts Associated with European and Japanese Populations of the Dock Bug Coreus marginatus (Coreoidea: Coreidae).},
journal = {Microbes and environments},
volume = {34},
number = {2},
pages = {219-222},
doi = {10.1264/jsme2.ME19011},
pmid = {31167992},
issn = {1347-4405},
mesh = {Animals ; Burkholderia/classification/genetics/isolation &amp; purification/*physiology ; DNA, Bacterial/genetics ; Europe ; Female ; Gastrointestinal Tract/anatomy &amp; histology/microbiology ; Heteroptera/anatomy &amp; histology/*microbiology ; Japan ; Male ; Phylogeny ; RNA, Ribosomal, 16S/genetics ; Sequence Analysis, DNA ; *Symbiosis ; },
abstract = {Insects of the heteropteran superfamilies Coreoidea and Lygaeoidea are consistently associated with symbionts of a specific group of the genus Burkholderia, called the &quot;stinkbug-associated beneficial and environmental (SBE)&quot; group. The symbiosis is maintained by the environmental transmission of symbionts. We investigated European and Japanese populations of the dock bug Coreus marginatus (Coreoidea: Coreidae). High nymphal mortality in reared aposymbiotic insects suggested an obligate host-symbiont association in this species. Molecular phylogenetic analyses based on 16S rRNA gene sequences revealed that all 173 individuals investigated were colonized by Burkholderia, which were further assigned to different subgroups of the SBE in a region-dependent pattern.},
}
@article {pmid31166165,
year = {2019},
author = {Jani, K and Feng, GD and Zhu, HH and Prakash, O and Bandal, J and Rale, V and Shouche, Y and Sharma, A},
title = {Chakrabartia godavariana gen. nov., sp. nov., a novel member of the family Sphingomonadaceae isolated from the Godavari River, India.},
journal = {International journal of systematic and evolutionary microbiology},
volume = {69},
number = {8},
pages = {2452-2458},
doi = {10.1099/ijsem.0.003512},
pmid = {31166165},
issn = {1466-5034},
mesh = {Bacterial Typing Techniques ; Base Composition ; DNA, Bacterial/genetics ; Fatty Acids/chemistry ; India ; Phospholipids/chemistry ; *Phylogeny ; RNA, Ribosomal, 16S/genetics ; Rivers/*microbiology ; Sequence Analysis, DNA ; Soil Microbiology ; Spermidine/analogs &amp; derivatives/chemistry ; Sphingomonadaceae/*classification/isolation &amp; purification ; Ubiquinone/chemistry ; },
abstract = {A Gram-stain-negative, aerobic, yellow-pigmented, oxidase-positive and rod-shaped bacterium, designated PRB40T, was isolated from the Godavari River in India during the course of 'Kumbh Mela', the world's largest mass gathering event. Phylogenetic analysis based on 16S rRNA gene sequences revealed that strain PRB40T formed a lineage within the family Sphingomonadaceae and was distinct from the most closely related genera Sphingorhabdus, Novosphingobiumand Sphingomonas with sequence similarity values ≤95.2 %. Growth of strain PRB40T occurred at 10-40 °C (optimum 30 °C), at pH 6.0-9.0 (pH 7.0) and with 0-0.5 % (w/v) NaCl concentration (0 %). The major respiratory quinone was ubiquinone-10 (Q-10). It contained C17 : 1ω6c, C14 : 0 2-OH, summed feature 3 (C16 : 1ω7c and/or C16 : 1ω6c) and summed feature 8 (C18 : 1ω7c and/or C18 : 1ω6c) as the major cellular fatty acids. The predominant polar lipids were phospholipid, phosphatidylethanolamine and sphingoglycolipid. It took sym-homospermidine as the major polyamine. The DNA G+C content based on its draft genome sequence was 63.7 mol%. The polyphasic taxonomic analyses indicated that strain PRB40T represents a novel species of a novel genus within the family Sphingomonadaceae, for which the name Chakrabartia godavariana gen. nov., sp. nov. is proposed. The type strain of Chakrabartia godavariana is PRB40T (=MCC 3406T=GDMCC 1.1197T=KCTC 52678T=LMG 29985T).},
}
@article {pmid31166074,
year = {2019},
author = {Guerrieri, A and Dong, L and Bouwmeester, HJ},
title = {Role and exploitation of underground chemical signaling in plants.},
journal = {Pest management science},
volume = {75},
number = {9},
pages = {2455-2463},
doi = {10.1002/ps.5507},
pmid = {31166074},
issn = {1526-4998},
support = {670211//H2020 European Research Council/ ; 793795//H2020 Marie Skłodowska-Curie Actions/ ; //Europen Research Council (ERC)/ ; },
abstract = {The soil ecosystem is composed of a mixture of living organisms and non-living matter as well as the complex interactions between them. In the past 100 years or so, agricultural soil ecosystems have been strongly affected by agricultural practices such as tillage and the use of pesticides and fertilizers, which strongly affect soil nutrient composition, pH and biodiversity. In modern pest management, however, the focus is gradually shifting from crop production through agricultural practices to soil ecosystem protection. In this review we discuss how the underground chemical signals secreted by plant roots play a role in keeping the soil ecosystem in balance and how they affect plant fitness by shaping the root biome, increasing nutrient availability, promoting symbiosis, and attracting beneficial organisms and repelling harmful ones, including other plants. We review a number of fascinating cases, such as signaling molecules with dual, positive and negative, functions and bacterial quorum sensing mimicking molecules. Finally, examples of how these compounds can be exploited in modern pest management are reviewed, and the prospects for future developments discussed. © 2019 The Authors. Pest Management Science published by John Wiley &amp; Sons Ltd on behalf of Society of Chemical Industry.},
}
@article {pmid31165947,
year = {2019},
author = {Sakamoto, K and Ogiwara, N and Kaji, T and Sugimoto, Y and Ueno, M and Sonoda, M and Matsui, A and Ishida, J and Tanaka, M and Totoki, Y and Shinozaki, K and Seki, M},
title = {Transcriptome analysis of soybean (Glycine max) root genes differentially expressed in rhizobial, arbuscular mycorrhizal, and dual symbiosis.},
journal = {Journal of plant research},
volume = {132},
number = {4},
pages = {541-568},
doi = {10.1007/s10265-019-01117-7},
pmid = {31165947},
issn = {1618-0860},
support = {23380042//Japan Society for the Promotion of Science/ ; },
mesh = {Gene Expression Profiling ; Gene Expression Regulation, Plant ; Genes, Plant ; Mycorrhizae/*metabolism ; Oligonucleotide Array Sequence Analysis ; Plant Roots/*metabolism/microbiology ; Rhizobium/*metabolism ; Root Nodules, Plant/metabolism/microbiology ; Soybeans/genetics/*metabolism ; Symbiosis ; },
abstract = {Soybean (Glycine max) roots establish associations with nodule-inducing rhizobia and arbuscular mycorrhizal (AM) fungi. Both rhizobia and AM fungi have been shown to affect the activity of and colonization by the other, and their interactions can be detected within host plants. Here, we report the transcription profiles of genes differentially expressed in soybean roots in the presence of rhizobial, AM, or rhizobial-AM dual symbiosis, compared with those in control (uninoculated) roots. Following inoculation, soybean plants were grown in a glasshouse for 6 weeks; thereafter their root transcriptomes were analyzed using an oligo DNA microarray. Among the four treatments, the root nodule number and host plant growth were highest in plants with dual symbiosis. We observed that the expression of 187, 441, and 548 host genes was up-regulated and 119, 1,439, and 1,298 host genes were down-regulated during rhizobial, AM, and dual symbiosis, respectively. The expression of 34 host genes was up-regulated in each of the three symbioses. These 34 genes encoded several membrane transporters, type 1 metallothionein, and transcription factors in the MYB and bHLH families. We identified 56 host genes that were specifically up-regulated during dual symbiosis. These genes encoded several nodulin proteins, phenylpropanoid metabolism-related proteins, and carbonic anhydrase. The nodulin genes up-regulated by the AM fungal colonization probably led to the observed increases in root nodule number and host plant growth. Some other nodulin genes were down-regulated specifically during AM symbiosis. Based on the results above, we suggest that the contribution of AM fungal colonization is crucial to biological N2-fixation and host growth in soybean with rhizobial-AM dual symbiosis.},
}
@article {pmid31164991,
year = {2019},
author = {Oishi, S and Moriyama, M and Koga, R and Fukatsu, T},
title = {Morphogenesis and development of midgut symbiotic organ of the stinkbug Plautia stali (Hemiptera: Pentatomidae).},
journal = {Zoological letters},
volume = {5},
number = {},
pages = {16},
doi = {10.1186/s40851-019-0134-2},
pmid = {31164991},
issn = {2056-306X},
abstract = {Diverse insects are intimately associated with microbial symbionts, which play a variety of biological roles in their adaptation to and survival in the natural environment. Such insects often possess specialized organs for hosting the microbial symbionts. What developmental processes and mechanisms underlie the formation of the host organs for microbial symbiosis is of fundamental biological interest but poorly understood. Here we investigate the morphogenesis of the midgut symbiotic organ and the process of symbiont colonization therein during the developmental course of the stinkbug Plautia stali. Upon hatching, the midgut is a simple and smooth tube. Subsequently, symbiont colonization to the posterior midgut occurs, and thickening and folding of the midgut epithelium proceed during the first instar period. By the second instar, rudimentary crypts have formed, and their inner cavities are colonized by the symbiotic bacteria. From the second instar to the fourth instar, while the alimentary tract grows and the posterior midgut is established as the symbiotic organ with numerous crypts, the anterior midgut and the posterior midgut are structurally and functionally isolated by a strong constriction in the middle. By the early fifth instar, the midgut symbiotic organ attains the maximal length, but toward the mid fifth instar, the basal region of each crypt starts to constrict and narrow, which deforms the midgut symbiotic organ as a whole into a shorter, thicker and twisted shape. By the late fifth instar to adulthood, the crypts are constricted off, by which the symbiotic bacteria are confined in the crypt cavities and isolated from the midgut main tract, and concurrently, the strong midgut constriction in the middle becomes loose and open, by which the food flow from the anterior midgut to the posterior midgut recovers. This study provides the most detailed and comprehensive descriptions ever reported on the morphogenesis of the symbiotic organ and the process of symbiont colonization in an obligatory insect-bacterium gut symbiotic system. Considering that P. stali is recently emerging as a useful model system for experimentally studying the intimate insect-microbe gut symbiosis, the knowledge obtained in this study establishes the foundation for the further development of this research field.},
}
@article {pmid31163164,
year = {2019},
author = {Havird, JC and Forsythe, ES and Williams, AM and Werren, JH and Dowling, DK and Sloan, DB},
title = {Selfish Mitonuclear Conflict.},
journal = {Current biology : CB},
volume = {29},
number = {11},
pages = {R496-R511},
doi = {10.1016/j.cub.2019.03.020},
pmid = {31163164},
issn = {1879-0445},
support = {F32 GM116361/GM/NIGMS NIH HHS/United States ; },
abstract = {Mitochondria, a nearly ubiquitous feature of eukaryotes, are derived from an ancient symbiosis. Despite billions of years of cooperative coevolution - in what is arguably the most important mutualism in the history of life - the persistence of mitochondrial genomes also creates conditions for genetic conflict with the nucleus. Because mitochondrial genomes are present in numerous copies per cell, they are subject to both within- and among-organism levels of selection. Accordingly, 'selfish' genotypes that increase their own proliferation can rise to high frequencies even if they decrease organismal fitness. It has been argued that uniparental (often maternal) inheritance of cytoplasmic genomes evolved to curtail such selfish replication by minimizing within-individual variation and, hence, within-individual selection. However, uniparental inheritance creates conditions for cytonuclear conflict over sex determination and sex ratio, as well as conditions for sexual antagonism when mitochondrial variants increase transmission by enhancing maternal fitness but have the side-effect of being harmful to males (i.e., 'mother's curse'). Here, we review recent advances in understanding selfish replication and sexual antagonism in the evolution of mitochondrial genomes and the mechanisms that suppress selfish interactions, drawing parallels and contrasts with other organelles (plastids) and bacterial endosymbionts that arose more recently. Although cytonuclear conflict is widespread across eukaryotes, it can be cryptic due to nuclear suppression, highly variable, and lineage-specific, reflecting the diverse biology of eukaryotes and the varying architectures of their cytoplasmic genomes.},
}
@article {pmid31162896,
year = {2019},
author = {Polienko, AK},
title = {[Peculiarities morphology and structure of the uroliths].},
journal = {Urologiia (Moscow, Russia : 1999)},
volume = {},
number = {2},
pages = {21-25},
pmid = {31162896},
issn = {1728-2985},
mesh = {Humans ; Microscopy/*methods ; Minerals/*analysis ; Urinary Calculi/*chemistry/*diagnostic imaging/ultrastructure ; },
abstract = {THE AIM: According to statistical data of a number of the countries, have an urolithic disease from 5% to 15% of the population today. A recurrence arises at 50-85% of patients. The purpose of this work was complex studying of morphology, structure, mineral structure of urolit, identification of regularities of their formation, establishment of interrelation between mineral and organic matter in structure of urolit.<br><br>MATERIALS: the urinary stones from the urology departments of hospitals and clinics of the Tomsk region (Russia).<br><br>METHOD: s: crystallomorphological (the study of the surface morphology of uroliths binocular and trinocular microscopes); polarizing optical (study of the mineral composition of uroliths on a polarizing microscope); x-ray crystallography (the study of spectral composition on the apparatus DRON-3); electron microscopic (study of the peculiarities of morphology of crystals in an electron microscope).<br><br>RESULTS: On features of morphology of a surface four types of urolit are allocated: druzovidny, sferolitovy, combined, korallovidny. Structural kinds of urolit: crystal and granular, dendritovidny, combined, rhythmic - zone. In structure of urolit the following types of rhythms are established: zone, granular, combined. In the urolitakh with rhythmic - the zone structure allocated elements of their building: kernel, layer, zone, rhythm. A mineral part of uric stones is presented by the crystals belonging to the classes: oxalates, phosphates, urat .<br><br>SUMMARY: The peculiarities of the morphology of the selected four types of uroliths: druzoid, with, combined, coral. Structural variations uroliths: crystal-grained Shelly, dendritic, combined, rhythmically zoned. In the structure of uroliths, the following types of rhythms: zoned, granular, combined. In urolith with rhythmically zoned structure selected elements of their structure: core, layer, area, rhythm.<br><br>DISCUSSION: Morphological and structural features of the structure of urolites, especially the presence of rhythmic zoning, due to the alternation of layers of mineral and organic matter, indicate a close relationship between the living organism and the organo-mineral aggregate in the human urinary system. With a high degree of confidence we can talk about the symbiosis of living and mineral matter in the human body; as a result of this symbiosis, organic-mineral formations are formed, which are often the further cause of some diseases (for example, urolithiasis and cholelithiasis).<br><br>CONCLUSION: The complex research of uric stones allows to obtain important information on their structure, structure and features of morphology. Morphological and structural features of the structure of urolit, in particular existence of the rhythmic zonality caused by alternation of layers of mineral and organic matter demonstrate close interrelation between a live organism and the organo-mineral unit in an urinary system of the person.},
}
@article {pmid31162893,
year = {2019},
author = {Shchuplova, EA and Kuzmin, MD},
title = {[The additional criterion for the diagnosis of purulent-destructive forms of acute pyelonephritis].},
journal = {Urologiia (Moscow, Russia : 1999)},
volume = {},
number = {2},
pages = {5-8},
pmid = {31162893},
issn = {1728-2985},
mesh = {Adult ; Aged ; Aged, 80 and over ; Bacteria/*isolation &amp; purification ; Coinfection/*diagnosis/microbiology ; DNA Probes ; Humans ; In Situ Hybridization, Fluorescence ; Middle Aged ; Pyelonephritis/*diagnosis/*microbiology ; Suppuration/diagnosis ; Young Adult ; },
abstract = {AIM: to develop an additional criterion for objective diagnosis of purulent-destructive forms of acute pyelonephritis.<br><br>MATERIALS AND METHODS: A total of 35 blood samples from patients with acute pyelonephritis aged from 19 to 85 years (mean age was 52 years) were studied. For the analysis, a classical bacteriological method of isolating blood culture and a modern molecular genetic method of fluorescent in situ hybridization (FISH) using DNA probes complementary to species-specific regions of the 16S rRNA gene of microorganisms were used. The obtained results were processed using the Statistica 6.0 program.<br><br>RESULTS: The bacteriological study showed that only in one patient (2.9%) a blood culture was positive, whereas with FISH, polymicrobial infection consisting of two associates was observed in five patients (14.3%), and 207 specific luminescence from different DNA probes were detected in blood samples. The associations of members of the Enterobacteriaceae with S. aureus were 2.4 times more frequent than associations of the Enterobacteriaceae with S. epidermidis, indicating a development of the polymicrobial infection and, accordingly, the development of purulent stage of acute pyelonephritis.<br><br>CONCLUSION: For the diagnosis of acute pyelonephritis, we suggest to use an additional criterion, which consists in applying of FISH method for the detection and simultaneous identification of bacteria that were adhered on the surface of erythrocytes and located intracellularly. This method may allow for the differential diagnosis of serous and purulent stages of acute pyelonephritis.},
}
@article {pmid31161314,
year = {2019},
author = {Prasad, S and Pandey, U and Saini, J and Ingalhalikar, M and Pal, PK},
title = {Atrophy of cerebellar peduncles in essential tremor: a machine learning-based volumetric analysis.},
journal = {European radiology},
volume = {},
number = {},
pages = {},
doi = {10.1007/s00330-019-06269-7},
pmid = {31161314},
issn = {1432-1084},
support = {ECR/2016/000808//Science and Engineering Research Board/ ; },
abstract = {BACKGROUND: Subtle cerebellar signs are frequently observed in essential tremor (ET) and may be associated with cerebellar dysfunction. This study aims to evaluate the macrostructural integrity of the superior, middle, and inferior cerebellar peduncles (SCP, MCP, ICP) and cerebellar gray and white matter (GM, WM) volumes in patients with ET, and compare these volumes between patients with and without cerebellar signs (ETc and ETnc).<br><br>METHODS: Forty patients with ET and 37 age- and gender-matched healthy controls were recruited. Atlas-based region-of-interest analysis of the SCP, MCP, and ICP and automated analysis of cerebellar GM and WM volumes were performed. Peduncular volumes were employed in a multi-variate classification framework to attempt discrimination of ET from controls.<br><br>RESULTS: Significant atrophy of bilateral MCP and ICP and bilateral cerebellar GM was observed in ET. Cerebellar signs were present in 20% of subjects with ET. Comparison of peduncular and cerebellar volumes between ETnc and ETc revealed atrophy of right SCP, bilateral MCP and ICP, and left cerebellar WM in ETc. The multi-variate classifier could discriminate between ET and controls with a test accuracy of 86.66%.<br><br>CONCLUSIONS: Patients with ET have significant atrophy of cerebellar peduncles, particularly the MCP and ICP. Additional atrophy of the SCP is observed in the ETc group. These abnormalities may contribute to the pathogenesis of cerebellar signs in ET.<br><br>KEY POINTS: • Patients with ET have significant atrophy of bilateral middle and inferior cerebellar peduncles and cerebellar gray matter in comparison with healthy controls. • Patients of ET with cerebellar signs have significant atrophy of right superior cerebellar peduncle, bilateral middle and inferior cerebellar peduncle, and left cerebellar white matter in comparison with ET without cerebellar signs. • A multi-variate classifier employing peduncular volumes could discriminate between ET and controls with a test accuracy of 86.66%.},
}
@article {pmid31161283,
year = {2019},
author = {Mu, X and Luo, J},
title = {Evolutionary analyses of NIN-like proteins in plants and their roles in nitrate signaling.},
journal = {Cellular and molecular life sciences : CMLS},
volume = {},
number = {},
pages = {},
doi = {10.1007/s00018-019-03164-8},
pmid = {31161283},
issn = {1420-9071},
support = {2662017QD001//Fundamental Research Funds for the Central Universities/ ; 2017CFB338//Hubei Province Natural Science Foundation of China/ ; 30500487//Research Start-up Fund for Henan Agricultural Universities/ ; },
abstract = {Nitrogen (N) is one of the most important essential macro-elements for plant growth and development, and nitrate represents the most abundant inorganic form of N in soils. The nitrate uptake and assimilation processes are finely tuned according to the available nitrate in the surroundings as well as by the internal finely coordinated signaling pathways. The NIN-like proteins (NLPs) harbor both RWP-RK, and Phox and Bem1 (PB1) domains, and they belong to the well-characterized plant-specific RWP-RK transcription factor gene family. NLPs are known to be involved in the nitrate signaling pathway by activating downstream target genes, and thus they are implicated in the primary nitrate response in the nucleus via their RWP-RK domains. The PB1 domain is a ubiquitous protein-protein interaction domain and it comprises another regulatory layer for NLPs via the protein interactions within NLPs or with other essential components. Recently, Ca2+-Ca2+ sensor protein kinase-NLP signaling cascades have been identified and they allow NLPs to have central roles in mediating the nitrate signaling pathway. NLPs play essential roles in many aspects of plant growth and development via the finely tuned nitrate signaling pathway. Furthermore, recent studies have highlighted the emerging roles played by NLPs in the N starvation response, nodule formation in legumes, N and P interactions, and root cap release in higher plants. In this review, we consider recent advances in the identification, evolution, molecular characteristics, and functions of the NLP gene family in plant growth and development.},
}
@article {pmid31160787,
year = {2019},
author = {Klimovich, A and Wittlieb, J and Bosch, TCG},
title = {Transgenesis in Hydra to characterize gene function and visualize cell behavior.},
journal = {Nature protocols},
volume = {14},
number = {7},
pages = {2069-2090},
doi = {10.1038/s41596-019-0173-3},
pmid = {31160787},
issn = {1750-2799},
abstract = {The freshwater polyp Hydra is a cnidarian used as a model organism in a number of fields, including the study of the origin and evolution of developmental mechanisms, aging, symbiosis and host-microbe interactions. Here, we describe a procedure for the establishment of stable transgenic Hydra lines by embryo microinjection. The three-stage protocol comprises (i) the design and preparation of a transgenic construct, (ii) the microinjection of the vector into early embryos of Hydra vulgaris, and (iii) the selection and enrichment of mosaic animals in order to develop uniformly transgenic clonal lines. The preparation of a transgenic construct requires ~2 weeks, and transgenic lines can be obtained within 3 months. The method allows constitutive or inducible gain- and loss-of-function approaches, as well as in vivo tracing of individual cells. Hydra polyps carrying transgenic cells reveal functional properties of the ancestral circuitry controlling animal development.},
}
@article {pmid31159921,
year = {2019},
author = {Hambleton, EA and Jones, VAS and Maegele, I and Kvaskoff, D and Sachsenheimer, T and Guse, A},
title = {Sterol transfer by atypical cholesterol-binding NPC2 proteins in coral-algal symbiosis.},
journal = {eLife},
volume = {8},
number = {},
pages = {},
doi = {10.7554/eLife.43923},
pmid = {31159921},
issn = {2050-084X},
support = {GU 1128/3-1//Deutsche Forschungsgemeinschaft/ ; FP7-PEOPLE-2013-CIG//European Commission/ ; 724715//Horizon 2020 Framework Programme/ ; Exploration Grant//Boehringer Ingelheim Stiftung/ ; LTF//European Molecular Biology Organization/ ; Excellence Initiative//Universität Heidelberg/ ; TRR83//Deutsche Forschungsgemeinschaft/ ; SFB1324//Deutsche Forschungsgemeinschaft/ ; },
abstract = {Reef-building corals depend on intracellular dinoflagellate symbionts that provide nutrients. Besides sugars, the transfer of sterols is essential for corals and other sterol-auxotrophic cnidarians. Sterols are important cell components, and variants of the conserved Niemann-Pick Type C2 (NPC2) sterol transporter are vastly up-regulated in symbiotic cnidarians. Types and proportions of transferred sterols and the mechanism of their transfer, however, remain unknown. Using different pairings of symbiont strains with lines of Aiptasia anemones or Acropora corals, we observe both symbiont- and host-driven patterns of sterol transfer, revealing plasticity of sterol use and functional substitution. We propose that sterol transfer is mediated by the symbiosis-specific, non-canonical NPC2 proteins, which gradually accumulate in the symbiosome. Our data suggest that non-canonical NPCs are adapted to the symbiosome environment, including low pH, and play an important role in allowing corals to dominate nutrient-poor shallow tropical seas worldwide.},
}
@article {pmid31159445,
year = {2019},
author = {Shen, G and Ju, W and Liu, Y and Guo, X and Zhao, W and Fang, L},
title = {Impact of Urea Addition and Rhizobium Inoculation on Plant Resistance in Metal Contaminated Soil.},
journal = {International journal of environmental research and public health},
volume = {16},
number = {11},
pages = {},
doi = {10.3390/ijerph16111955},
pmid = {31159445},
issn = {1660-4601},
abstract = {Legume-rhizobium symbiosis has been heavily investigated for their potential to enhance plant metal resistance in contaminated soil. However, the extent to which plant resistance is associated with the nitrogen (N) supply in symbiont is still uncertain. This study investigates the effect of urea or/and rhizobium (Sinorhizobium meliloti) application on the growth of Medicago sativa and resistance in metals contaminated soil (mainly with Cu). The results show that Cu uptake in plant shoots increased by 41.7%, 69%, and 89.3% with urea treatment, rhizobium inoculation, and their combined treatment, respectively, compared to the control group level. In plant roots, the corresponding values were 1.9-, 1.7-, and 1.5-fold higher than the control group values, respectively. Statistical analysis identified that N content was the dominant variable contributing to Cu uptake in plants. Additionally, a negative correlation was observed between plant oxidative stress and N content, indicating that N plays a key role in plant resistance. Oxidative damage decreased after rhizobium inoculation as the activities of antioxidant enzymes (catalase and superoxide dismutase in roots and peroxidase in plant shoots) were stimulated, enhancing plant resistance and promoting plant growth. Our results suggest that individual rhizobium inoculation, without urea treatment, is the most recommended approach for effective phytoremediation of contaminated land.},
}
@article {pmid31158486,
year = {2019},
author = {Titus, BM and Benedict, C and Laroche, R and Gusmão, LC and Van Deusen, V and Chiodo, T and Meyer, CP and Berumen, ML and Bartholomew, A and Yanagi, K and Reimer, JD and Fujii, T and Daly, M and Rodríguez, E},
title = {Phylogenetic relationships among the clownfish-hosting sea anemones.},
journal = {Molecular phylogenetics and evolution},
volume = {139},
number = {},
pages = {106526},
doi = {10.1016/j.ympev.2019.106526},
pmid = {31158486},
issn = {1095-9513},
abstract = {The clownfish-sea anemone symbiosis has been a model system for understanding fundamental evolutionary and ecological processes. However, our evolutionary understanding of this symbiosis comes entirely from studies of clownfishes. A holistic understanding of a model mutualism requires systematic, biogeographic, and phylogenetic insight into both partners. Here, we conduct the largest phylogenetic analysis of sea anemones (Order Actiniaria) to date, with a focus on expanding the biogeographic and taxonomic sampling of the 10 nominal clownfish-hosting species. Using a combination of mtDNA and nuDNA loci we test (1) the monophyly of each clownfish-hosting family and genus, (2) the current anemone taxonomy that suggests symbioses with clownfishes evolved multiple times within Actiniaria, and (3) whether, like the clownfishes, there is evidence that host anemones have a Coral Triangle biogeographic origin. Our phylogenetic reconstruction demonstrates widespread poly- and para-phyly at the family and genus level, particularly within the family Stichodactylidae and genus Stichodactyla, and suggests that symbioses with clownfishes evolved minimally three times within sea anemones. We further recover evidence for a Tethyan biogeographic origin for some clades. Our data provide the first evidence that clownfish and some sea anemone hosts have different biogeographic origins, and that there may be cryptic species of host anemones. Finally, our findings reflect the need for a major taxonomic revision of the clownfish-hosting sea anemones.},
}
@article {pmid31156674,
year = {2019},
author = {Gómez-Gallego, T and Benabdellah, K and Merlos, MA and Jiménez-Jiménez, AM and Alcon, C and Berthomieu, P and Ferrol, N},
title = {The Rhizophagus irregularis Genome Encodes Two CTR Copper Transporters That Mediate Cu Import Into the Cytosol and a CTR-Like Protein Likely Involved in Copper Tolerance.},
journal = {Frontiers in plant science},
volume = {10},
number = {},
pages = {604},
doi = {10.3389/fpls.2019.00604},
pmid = {31156674},
issn = {1664-462X},
abstract = {Arbuscular mycorrhizal fungi increase fitness of their host plants under Cu deficient and toxic conditions. In this study, we have characterized two Cu transporters of the CTR family (RiCTR1 and RiCTR2) and a CTR-like protein (RiCTR3A) of Rhizophagus irregularis. Functional analyses in yeast revealed that RiCTR1 encodes a plasma membrane Cu transporter, RiCTR2 a vacuolar Cu transporter and RiCTR3A a plasma membrane protein involved in Cu tolerance. RiCTR1 was more highly expressed in the extraradical mycelia (ERM) and RiCTR2 in the intraradical mycelia (IRM). In the ERM, RiCTR1 expression was up-regulated by Cu deficiency and down-regulated by Cu toxicity. RiCTR2 expression increased only in the ERM grown under severe Cu-deficient conditions. These data suggest that RiCTR1 is involved in Cu uptake by the ERM and RiCTR2 in mobilization of vacuolar Cu stores. Cu deficiency decreased mycorrhizal colonization and arbuscule frequency, but increased RiCTR1 and RiCTR2 expression in the IRM, which suggest that the IRM has a high Cu demand. The two alternatively spliced products of RiCTR3, RiCTR3A and RiCTR3B, were more highly expressed in the ERM. Up-regulation of RiCTR3A by Cu toxicity and the yeast complementation assays suggest that RiCTR3A might function as a Cu receptor involved in Cu tolerance.},
}
@article {pmid31156662,
year = {2019},
author = {Pucciariello, C and Boscari, A and Tagliani, A and Brouquisse, R and Perata, P},
title = {Exploring Legume-Rhizobia Symbiotic Models for Waterlogging Tolerance.},
journal = {Frontiers in plant science},
volume = {10},
number = {},
pages = {578},
doi = {10.3389/fpls.2019.00578},
pmid = {31156662},
issn = {1664-462X},
abstract = {Unexpected and increasingly frequent extreme precipitation events result in soil flooding or waterlogging. Legumes have the capacity to establish a symbiotic relationship with endosymbiotic atmospheric dinitrogen-fixing rhizobia, thus contributing to natural nitrogen soil enrichment and reducing the need for chemical fertilization. The impact of waterlogging on nitrogen fixation and legume productivity needs to be considered for crop improvement. This review focuses on the legumes-rhizobia symbiotic models. We aim to summarize the mechanisms underlying symbiosis establishment, nodule development and functioning under waterlogging. The mechanisms of oxygen sensing of the host plant and symbiotic partner are considered in view of recent scientific advances.},
}
@article {pmid31156660,
year = {2019},
author = {von Sivers, L and Jaspar, H and Johst, B and Roese, M and Bitterlich, M and Franken, P and Kühn, C},
title = {Brassinosteroids Affect the Symbiosis Between the AM Fungus Rhizoglomus irregularis and Solanaceous Host Plants.},
journal = {Frontiers in plant science},
volume = {10},
number = {},
pages = {571},
doi = {10.3389/fpls.2019.00571},
pmid = {31156660},
issn = {1664-462X},
abstract = {Together with several proteins involved in brassinosteroid (BR) signaling and synthesis, the membrane steroid binding protein 1 (MSBP1) was identified within the interactome of the sucrose transporter of tomato (SlSUT2). We asked whether MSBP1 is also involved in BR signaling as assumed for the AtMSBP1 protein from Arabidopsis and whether it impacts root colonization with arbuscular mycorrhizal (AM) fungi in a similar way as shown previously for SlSUT2. In addition, we asked whether brassinosteroids per se affect efficiency of root colonization by AM fungi. We carried out a set of experiments with transgenic tobacco plants with increased and decreased MSBP1 expression levels. We investigated the plant and the mycorrhizal phenotype of these transgenic plants and tested the involvement of MSBP1 in BR metabolism by application of epi-brassinolide and brassinazole, an inhibitor of BR biosynthesis. We show that the phenotype of the transgenic tobacco plants with increased or reduced MSBP1 expression is consistent with an inhibitory role of MSBP1 in BR signaling. MSBP1 overexpression could be mimicked by brassinazole treatment. Interestingly, manipulation of MSBP1 expression in transgenic tobacco plants not only affected plant growth and development, but also the host plant responses toward colonization with AM fungi, as well as arbuscular architecture. Moreover, we observed that brassinosteroids indeed have a direct impact on the nutrient exchange in AM symbiosis and on the biomass production of colonized host plants. Furthermore, arbuscular morphology is affected by changes in MSBP1 expression and brassinolide or brassinazole treatments. We conclude that host plant growth responses and nutrient exchange within the symbiosis with AM fungi is controlled by brassinosteroids and might be impeded by the MSBP1 protein.},
}
@article {pmid31156595,
year = {2019},
author = {Bertolazi, AA and de Souza, SB and Ruas, KF and Campostrini, E and de Rezende, CE and Cruz, C and Melo, J and Colodete, CM and Varma, A and Ramos, AC},
title = {Inoculation With Piriformospora indica Is More Efficient in Wild-Type Rice Than in Transgenic Rice Over-Expressing the Vacuolar H+-PPase.},
journal = {Frontiers in microbiology},
volume = {10},
number = {},
pages = {1087},
doi = {10.3389/fmicb.2019.01087},
pmid = {31156595},
issn = {1664-302X},
abstract = {Achieving food security in a context of environmental sustainability is one of the main challenges of the XXI century. Two competing strategies to achieve this goal are the use of genetically modified plants and the use of plant growth promoting microorganisms (PGPMs). However, few studies assess the response of genetically modified plants to PGPMs. The aim of this study was to compare the response of over-expressing the vacuolar H+-PPase (AVP) and wild-type rice types to the endophytic fungus; Piriformospora indica. Oryza sativa plants (WT and AVP) were inoculated with P. indica and 30 days later, morphological, ecophysiological and bioenergetic parameters, and nutrient content were assessed. AVP and WT plant heights were strongly influenced by inoculation with P. indica, which also promoted increases in fresh and dry matter of shoot in both genotypes. This may be related with the stimulatory effect of P. indica on ecophysiological parameters, especially photosynthetic rate, stomatal conductance, intrinsic water use efficiency and carboxylation efficiency. However, there were differences between the genotypes concerning the physiological mechanisms leading to biomass increment. In WT plants, inoculation with P. indica stimulated all H+ pumps. However, in inoculated AVP plants, H+-PPase was stimulated, but P- and V-ATPases were inhibited. Fungal inoculation enhanced nutrient uptake in both shoots and roots of WT and AVP plants, compared to uninoculated plants; but among inoculated genotypes, the nutrient uptake was lower in AVP than in WT plants. These results clearly demonstrate that the symbiosis between P. indica and AVP plants did not benefit those plants, which may be related to the inefficient colonization of this fungus on the transgenic plants, demonstrating an incompatibility of this symbiosis, which needs to be further studied.},
}
@article {pmid31153721,
year = {2019},
author = {Sobotková, K and Parker, W and Levá, J and Růžková, J and Lukeš, J and Jirků Pomajbíková, K},
title = {Helminth Therapy - From the Parasite Perspective.},
journal = {Trends in parasitology},
volume = {35},
number = {7},
pages = {501-515},
doi = {10.1016/j.pt.2019.04.009},
pmid = {31153721},
issn = {1471-5007},
abstract = {Studies in animal models and humans suggest that intentional exposure to helminths or helminth-derived products may hold promise for treating chronic inflammatory-associated diseases (CIADs). Although the mechanisms underlying 'helminth therapy' are being evaluated, little attention has been paid to the actual organisms in use. Here we examine the notion that, because of the complexity of biological symbiosis, intact helminths rather than helminth-derived products are likely to prove more useful for clinical purposes. Further, weighing potential cost/benefit ratios of various helminths along with other factors, such as feasibility of production, we argue that the four helminths currently in use for CIAD treatments in humans were selected more by happenstance than by design, and that other candidates not yet tested may prove superior.},
}
@article {pmid31152905,
year = {2019},
author = {Rostami, M and Rostami, S},
title = {Effect of salicylic acid and mycorrhizal symbiosis on improvement of fluoranthene phytoremediation using tall fescue (Festuca arundinacea Schreb).},
journal = {Chemosphere},
volume = {232},
number = {},
pages = {70-75},
doi = {10.1016/j.chemosphere.2019.05.171},
pmid = {31152905},
issn = {1879-1298},
mesh = {*Biodegradation, Environmental ; Biomass ; Festuca/*metabolism/microbiology ; Fluorenes ; Mycorrhizae/*physiology ; Plant Growth Regulators ; Plant Roots/growth &amp; development ; Polycyclic Aromatic Hydrocarbons/*metabolism ; Salicylic Acid/*metabolism ; Soil ; Soil Microbiology ; Soil Pollutants/*metabolism ; Symbiosis ; },
abstract = {Polycyclic aromatic hydrocarbons are an important group of pollutants that are widely distributed in the environment. The present study aimed to investigate the effect of salicylic acid (a phenolic phytohormone) and mycorrhizal fungi on the growth and phytoremediation ability of tall fescue in the soil contaminated by fluoranthene. The initial concentrations of fluoranthene in this study were 100, 200, and 300 mg kg-1. The experimental treatments were included: T0 uncultivated soil; T1 cultivated soil with tall fescue; T2 cultivated soil with tall fescue + salicylic acid application; T3 cultivated soil with tall fescue + application of mycorrhizal fungi; T4 cultivated soil with tall fescue + salicylic acid and mycorrhizal fungi application; and P planting tall fescue in uncontaminated soil. The removal of fluoranthene was measured after 90 days. Furthermore, at the end of the experiment, the amount of shoot and root biomass, soil bacteria, and dehydrogenase activity were measured. According to the results, in all levels of contamination, removal of fluoranthene in cultivated treatments significantly was higher than uncultivated treatments. Increasing the concentration of fluoranthene had a negative effect on the shoot and root biomass in different treatments. Salicylic acid and mycorrhizal fungi significantly increased the shoot and root biomass and also the number of soil bacteria, dehydrogenase activity, and fluoranthene removal in T2, T3, and T4 treatments compared to T1. At the highest concentration of fluoranthene, as a result of simultaneous application of salicylic acid and mycorrhizal fungi (T4), the fluoranthene removal increased by 63, 21, 13, and 16% in comparison with T0, T1, T2, and T3, respectively. Based on the results, salicylic acid and mycorrhizal fungi, either alone or in combination, have a significant effect on the improvement of phytoremediation potential in tall fescue.},
}
@article {pmid31152194,
year = {2019},
author = {Ghorbani, A and Omran, VOG and Razavi, SM and Pirdashti, H and Ranjbar, M},
title = {Piriformospora indica confers salinity tolerance on tomato (Lycopersicon esculentum Mill.) through amelioration of nutrient accumulation, K+/Na+ homeostasis and water status.},
journal = {Plant cell reports},
volume = {38},
number = {9},
pages = {1151-1163},
doi = {10.1007/s00299-019-02434-w},
pmid = {31152194},
issn = {1432-203X},
mesh = {Basidiomycota/*physiology ; Homeostasis ; Lycopersicon esculentum/genetics/*microbiology/physiology ; Nutrients/*metabolism ; Potassium/*metabolism ; Salinity ; Salt Tolerance ; Sodium/*metabolism ; Stress, Physiological ; Symbiosis ; Water/*metabolism ; },
abstract = {KEY MESSAGE: Piriformospora indica confers salt tolerance in tomato seedlings by increasing the uptake of nutrients such as N, P and Ca, improving K+/Na+ homoeostasis by regulating the expression of NHXs, SOS1 and CNGC15 genes, maintaining water status by regulating the expression of aquaporins. Piriformospora indica, an endophytic basidiomycete, has been shown to increase the growth and improve the plants tolerance to stressful conditions, especially salinity, by establishing the arbuscular mycorrhiza-like symbiotic relationship in various plant hosts. In the present research, the effect of NaCl treatment (150 mM) and P. indica inoculation on growth, accumulation of nutrients, the transcription level of genes involved in ionic homeostasis (NHXs, SOS1 and CNGC15) and regulating water status (PIP1;2, PIP2;4, TIP1;1 and TIP2;2) in roots and leaves of tomato seedlings were investigated. The P. indica improved the uptake of N, P, Ca and K, and reduced Na accumulation, and had no significant effect on Cl accumulation in roots and leaves. The endophytic fungus also increased in K+/Na+ ratio in roots and leaves of tomato by regulating the expression of NHX isoforms and upregulating SOS1 and CNGC15 expression. Salinity stress increased the transcription of PIP2;4 gene and reduced the transcription of PIP1;2, TIP1;1 and TIP2;2 genes compared to the control treatment. However, P. indica inoculation upregulated the expression of PIP1;2 and PIP2;4 genes versus non-inoculated plants but did not have a significant effect on TIP1;1 and TIP2;2 expression. These results conclude that the positive effects of P. indica on nutrients accumulation, ionic homeostasis and water status lead to the increased salinity tolerance and the improved plant growth under NaCl treatment.},
}
@article {pmid31152017,
year = {2019},
author = {Pesce, C and Oshone, R and Hurst, SG and Kleiner, VA and Tisa, LS},
title = {Stable Transformation of the Actinobacteria Frankia spp.},
journal = {Applied and environmental microbiology},
volume = {85},
number = {15},
pages = {},
doi = {10.1128/AEM.00957-19},
pmid = {31152017},
issn = {1098-5336},
abstract = {A stable and efficient plasmid transfer system was developed for nitrogen-fixing symbiotic actinobacteria of the genus Frankia, a key first step in developing a genetic system. Four derivatives of the broad-host-range cloning vector pBBR1MCS were successfully introduced into different Frankia strains by a filter mating with Escherichia coli strain BW29427. Initially, plasmid pHKT1 that expresses green fluorescent protein (GFP) was introduced into Frankia casuarinae strain CcI3 at a frequency of 4.0 × 10-3, resulting in transformants that were tetracycline resistant and exhibited GFP fluorescence. The presence of the plasmid was confirmed by molecular approaches, including visualization on agarose gel and PCR. Several other pBBR1MCS plasmids were also introduced into F. casuarinae strain CcI3 and other Frankia strains at frequencies ranging from 10-2 to 10-4, and the presence of the plasmids was confirmed by PCR. The plasmids were stably maintained for over 2 years and through passage in a plant host. As a proof of concept, a salt tolerance candidate gene from the highly salt-tolerant Frankia sp. strain CcI6 was cloned into pBBR1MCS-3. The resulting construct was introduced into the salt-sensitive F. casuarinae strain CcI3. Endpoint reverse transcriptase PCR (RT-PCR) showed that the gene was expressed in F. casuarinae strain CcI3. The expression provided an increased level of salt tolerance for the transformant. These results represent stable plasmid transfer and exogenous gene expression in Frankia spp., overcoming a major hurdle in the field. This step in the development of genetic tools in Frankia spp. will open up new avenues for research on actinorhizal symbiosis.IMPORTANCE The absence of genetic tools for Frankia research has been a major hindrance to the associated field of actinorhizal symbiosis and the use of the nitrogen-fixing actinobacteria. This study reports on the introduction of plasmids into Frankia spp. and their functional expression of green fluorescent protein and a cloned gene. As the first step in developing genetic tools, this technique opens up the field to a wide array of approaches in an organism with great importance to and potential in the environment.},
}
@article {pmid31150238,
year = {2019},
author = {Zhang, W and Mace, WJ and Matthew, C and Card, SD},
title = {The Impact of Endophyte Infection, Seed Aging, and Imbibition on Selected Sugar Metabolite Concentrations in Seed.},
journal = {Journal of agricultural and food chemistry},
volume = {67},
number = {25},
pages = {6921-6929},
doi = {10.1021/acs.jafc.9b01618},
pmid = {31150238},
issn = {1520-5118},
mesh = {Endophytes/*physiology ; Epichloe/*physiology ; Festuca/growth &amp; development/metabolism/*microbiology/physiology ; Seeds/*growth &amp; development/metabolism/microbiology/physiology ; Sugars/*metabolism ; Symbiosis ; },
abstract = {This study investigated effects of seed aging and imbibition on sugar metabolite concentrations in Epichloë endophyte-infected and endophyte-free seed of tall fescue (Festuca arundinacea Schreb.). Two treatments, namely, accelerated aging and imbibition, were applied to the seeds, with embryo and endosperm tissues analyzed separately. Gas chromatography with flame ionization detection was employed for analysis of sugar metabolites within the seed tissues. Mannitol, ribitol, and trehalose were more abundant in embryo than endosperm tissues and were identified at consistently higher concentrations within endophyte-infected compared to endophyte-free seeds. The ratio of raffinose to sucrose significantly increased with seed aging in both endophyte-free and endophyte-infected embryo tissues, while significantly lower concentrations of trehalose were detected in tissues dissected from aged-seed regardless of endophyte status. This research provides fundamental insight into the metabolic details of endophyte survival in seed and provides a first evaluation of key carbohydrates present in the fungal-plant symbiosis.},
}
@article {pmid31150064,
year = {2019},
author = {Weis, VM},
title = {Cell biology of coral symbiosis: Foundational study can inform solutions to the coral reef crisis.},
journal = {Integrative and comparative biology},
volume = {},
number = {},
pages = {},
doi = {10.1093/icb/icz067},
pmid = {31150064},
issn = {1557-7023},
abstract = {Coral reefs are faced with almost complete destruction by the end of the century due to global warming unless humanity can cap global temperature rise. There is now a race to develop a diverse set of solutions to save coral reefs. In this perspective, a case is made for understanding of the cell biology of coral-dinoflagellate symbiosis to help inform development of solutions for saving reefs. Laboratory model systems for the study of coral symbiosis, including the sea anemone Exaiptasia pallida, are featured as valuable tools in the fight to save corals. The roles of host innate immunity and inter-partner nutrient dynamics in the onset, ongoing maintenance and dysregulation of symbiosis are reviewed and discussed. Key innate immune genes and pathways, such as glycan-lectin interactions, the sphingosine rheostat and the cytokine TGFβ are shown to modulate a host immune response in the symbiotic state. An upset in the homeostatic inorganic nutrient balance during heat stress and high exogenous nutrient availability is credited with driving the partnership towards dysregulation and coral bleaching. Specific examples are given where knowledge of the cell biology of symbiosis is informing the development of solutions, including studies showing clear limitations in the value of partner switching and acclimatization protocols. Finally, emphasis is placed on rapid advancement of knowledge to try to meet the urgent need for solutions. This includes real-time open communication with colleagues on successes and failures, sharing of resources and information, and working together in the spirit of a collective mission to save coral reefs.},
}
@article {pmid31148385,
year = {2019},
author = {Fernandes, S and Vinnakota, R and Kumar, J and Kale, V and Limaye, L},
title = {Improved neural differentiation of normal and abnormal induced pluripotent stem cell lines in the presence of valproic acid.},
journal = {Journal of tissue engineering and regenerative medicine},
volume = {13},
number = {8},
pages = {1482-1496},
doi = {10.1002/term.2904},
pmid = {31148385},
issn = {1932-7005},
support = {BT/PR12696/MED/31/287/2014//Department of Biotechnology, Ministry of Science and Technology/ ; },
abstract = {During the generation of induced pluripotent stem cell (iPSC) lines from cord blood CD34+ cells, a line having complete trisomy of Chromosome 1 and deletion of q23 to qTer of Chromosome 11 was accidentally developed in our lab. The abnormality was consistently detected even at higher passages. These chromosomal anomalies are known to manifest neurological developmental defects. In order to examine if such defects occur during in vitro differentiation of the cell line, we set up a protocol for neural differentiation. Valproic acid (VPA) was earlier reported by us to enhance neural differentiation of placental mesenchymal stem cells. Here, we induced normal and abnormal iPSC lines to neural lineage with/without VPA. Neural differentiation was observed in all four sets, but for both the iPSCs lines, VPA sets performed better. The characteristics tested were morphology, neural filament length, detection of neural markers, and electrophysiology. In summary, the karyotypically abnormal line exhibited efficient neural differentiation. This iPSC line may serve as a useful tool to study abnormalities associated with trisomy 1 and deletion of q23 to qTer of Chromosome 11.},
}
@article {pmid31148173,
year = {2019},
author = {An, J and Zeng, T and Ji, C and de Graaf, S and Zheng, Z and Xiao, TT and Deng, X and Xiao, S and Bisseling, T and Limpens, E and Pan, Z},
title = {A Medicago truncatula SWEET transporter implicated in arbuscule maintenance during arbuscular mycorrhizal symbiosis.},
journal = {The New phytologist},
volume = {224},
number = {1},
pages = {396-408},
doi = {10.1111/nph.15975},
pmid = {31148173},
issn = {1469-8137},
support = {2018YFD1000103//National Key Research and Development Program of China/ ; 2017YFD0202001//National Key Research and Development Program of China/ ; 31521092//National Natural Science Foundation of China/ ; Gui Ke AA 18118046//Science and Technology Major Project of Guangxi/ ; GDT20174200001//High-End Foreign Experts Project/ ; 2662018JC039//Fundamental Research Funds for the Central Universities/ ; ERC-2011-AdG294790/ERC_/European Research Council/International ; 530-6CDP21//Koninklijke Nederlandse Akademie van Wetenschappen/ ; },
abstract = {Plants form a mutualistic symbiosis with arbuscular mycorrhizal (AM) fungi, which facilitates the acquisition of scarce minerals from the soil. In return, the host plants provide sugars and lipids to its fungal partner. However, the mechanism by which the AM fungi obtain sugars from the plant has remained elusive. In this study we investigated the role of potential SWEET family sugar exporters in AM symbiosis in Medicago truncatula. We show that M. truncatula SWEET1b transporter is strongly upregulated in arbuscule-containing cells compared to roots and localizes to the peri-arbuscular membrane, across which nutrient exchange takes place. Heterologous expression of MtSWEET1b in a yeast hexose transport mutant showed that it mainly transports glucose. Overexpression of MtSWEET1b in M. truncatula roots promoted the growth of intraradical mycelium during AM symbiosis. Surprisingly, two independent Mtsweet1b mutants, which are predicted to produce truncated protein variants impaired in glucose transport, exhibited no significant defects in AM symbiosis. However, arbuscule-specific overexpression of MtSWEET1bY57A/G58D , which are considered to act in a dominant-negative manner, resulted in enhanced collapse of arbuscules. Taken together, our results reveal a (redundant) role for MtSWEET1b in the transport of glucose across the peri-arbuscular membrane to maintain arbuscules for a healthy mutually beneficial symbiosis.},
}
@article {pmid31144716,
year = {2019},
author = {McDaneld, TG and Kuehn, LA and Keele, JW},
title = {Microbiome of the upper nasal cavity of beef calves prior to weaning12.},
journal = {Journal of animal science},
volume = {97},
number = {6},
pages = {2368-2375},
doi = {10.1093/jas/skz119},
pmid = {31144716},
issn = {1525-3163},
mesh = {Animals ; Bacteria/*classification/genetics ; Biodiversity ; Cattle/*microbiology ; Cattle Diseases/*epidemiology/microbiology ; High-Throughput Nucleotide Sequencing/veterinary ; Incidence ; *Microbiota ; Nasal Cavity/microbiology ; RNA, Bacterial/genetics ; RNA, Ribosomal, 16S/genetics ; Respiratory Tract Infections/epidemiology/microbiology/*veterinary ; Sequence Analysis, DNA ; Symbiosis ; United States/epidemiology ; Weaning ; },
abstract = {Disease incidence is intimately associated with an animal's commensal bacteria populations (microbiome), as microbes that are involved with morbidity and mortality are commonly found in animals with no sign of disease. An understanding of the animal's resident respiratory pathogens, in the upper nasal cavity prior to weaning, may help us to understand the impact of these pathogens on incidence of respiratory disease. For this research, the overall goal was to characterize bacterial populations associated with calves at an early age and through time periods prior to weaning in 3 herds at the U.S. Meat Animal Research Center. Nasal swabs from the upper nasal cavity were collected at initial vaccination (approximately 40 d of age), preconditioning (approximately 130 d of age), and weaning (approximately 150 d of age) in 2015 and 2016. DNA was extracted from nasal swabs and combined into 2 pools of 10 animals for each sampling time point, in each herd, for a total of 6 pools at each sampling time point and 18 pools for all sampling time points within each year. To evaluate and compare the microbiome of each pooled sample, hypervariable regions 1 through 3 along the 16S ribosomal RNA (rRNA) gene were amplified by PCR and sequenced using next-generation sequencing (Illumina MiSeq) for identification of the bacterial taxa present. Alpha and beta diversity were also measured. Overall, microbial communities were different between combinations of sampling year, herd location, and sampling time prior to weaning as shown by beta diversity. Analysis of these specific respiratory pathogens prior to weaning will present a clearer picture of the distribution of microbial populations in animals prior to weaning and not exhibiting clinical signs of respiratory disease. Therefore, evaluation of the animal's resident bacterial populations in the upper nasal cavity during different phases of the beef production system may help us to understand the impact of the microbiome on incidence of respiratory disease in cattle.},
}
@article {pmid31141960,
year = {2019},
author = {Ali, A and Imran Ghani, M and Li, Y and Ding, H and Meng, H and Cheng, Z},
title = {Hiseq Base Molecular Characterization of Soil Microbial Community, Diversity Structure, and Predictive Functional Profiling in Continuous Cucumber Planted Soil Affected by Diverse Cropping Systems in an Intensive Greenhouse Region of Northern China.},
journal = {International journal of molecular sciences},
volume = {20},
number = {11},
pages = {},
doi = {10.3390/ijms20112619},
pmid = {31141960},
issn = {1422-0067},
support = {2016KTCL02-01//Shaanxi Provincial Sci-Tech Innovation Plan/ ; 31772293//National Natural Science Foundation/ ; },
abstract = {Cover crops are key determinants of the ecological stability and sustainability of continuous cropping soils. However, their agro-ecological role in differentially reshaping the microbiome structure and functioning under a degraded agroecosystem remains poorly investigated. Therefore, structural and metabolic changes in soil bacterial community composition in response to diverse plant species were assessed. Winter catch leafy vegetables crops were introduced as cover plants in a cucumber-fallow period. The results indicate that cover crop diversification promoted beneficial changes in soil chemical and biological attributes, which increased crop yields in a cucumber double-cropping system. Illumina high-throughput sequencing of 16S rRNA genes indicated that the bacterial community composition and diversity changed through changes in the soil properties. Principal component analysis (PCA) coupled with non-metric multidimensional scaling (NMDS) analysis reveals that the cover planting shaped the soil microbiome more than the fallow planting (FC). Among different cropping systems, spinach-cucumber (SC) and non-heading Chinese cabbage-cucumber (NCCC) planting systems greatly induced higher soil nutrient function, biological activity, and bacterial diversity, thus resulting in higher cucumber yield. Quantitative analysis of linear discriminant analysis effect size (LEfSe) indicated that Proteobacteria, Actinobacteria, Bacteroidetes, and Acidobacteria were the potentially functional and active soil microbial taxa. Rhizospheres of NCCC, leaf lettuce-cucumber (LLC), coriander-cucumber (CC), and SC planting systems created hotspots for metabolic capabilities of abundant functional genes, compared to FC. In addition, the predictive metabolic characteristics (metabolism and detoxification) associated with host-plant symbiosis could be an important ecological signal that provides direct evidence of mediation of soil structure stability. Interestingly, the plant density of non-heading Chinese cabbage and spinach species was capable of reducing the adverse effect of arsenic (As) accumulation by increasing the function of the arsenate reductase pathway. Redundancy analysis (RDA) indicated that the relative abundance of the core microbiome can be directly and indirectly influenced by certain environmental determinants. These short-term findings stress the importance of studying cover cropping systems as an efficient biological tool to protect the ecological environment. Therefore, we can speculate that leafy crop diversification is socially acceptable, economically justifiable, and ecologically adaptable to meet the urgent demand for intensive cropping systems to promote positive feedback between crop-soil sustainable intensification.},
}
@article {pmid31141718,
year = {2019},
author = {Liu, XL and Ye, S and Cheng, CY and Li, HW and Lu, B and Yang, WJ and Yang, JS},
title = {Identification and characterization of a symbiotic agglutination-related C-type lectin from the hydrothermal vent shrimp Rimicaris exoculata.},
journal = {Fish &amp; shellfish immunology},
volume = {92},
number = {},
pages = {1-10},
doi = {10.1016/j.fsi.2019.05.057},
pmid = {31141718},
issn = {1095-9947},
abstract = {Rimicaris exoculata (Decapoda: Bresiliidae) is one of the dominant species of hydrothermal vent communities, which inside its gill chamber harbors ectosymbioses with taxonomic invariability while compositional flexibility. Several studies have revealed that the establishment of symbiosis can be initiated and selected by innate immunity-related pattern recognition receptors (PRRs), such as C-type lectins (CTLs). In this research, a CTL was identified in R. exoculata (termed RCTL), which showed high expression at both mRNA and protein levels in the scaphognathite, an organ where the ectosymbionts are attached outside its setae. Linear correlationships were observed between the relative quantities of two major symbionts and the expression of RCTL based on analyzing different shrimp individuals. The recombinant protein of RCTL could recognize and agglutinate the cultivable γ-proteobacterium of Escherichia coli in a Ca2+-dependent manner, obeying a dose-dependent and time-cumulative pattern. Unlike conventional crustacean CTLs, the involvement of RCTL could not affect the bacterial growth, which is a key issue for the successful establishment of symbiosis. These results implied that RCTL might play a critical role in symbiotic recognition and attachment to R. exoculata. It also provides insights to understand how R. exoculata adapted to such a chemosynthesis-based environment.},
}
@article {pmid31140970,
year = {2019},
author = {Lynn-Bell, NL and Strand, MR and Oliver, KM},
title = {Bacteriophage acquisition restores protective mutualism.},
journal = {Microbiology (Reading, England)},
volume = {165},
number = {9},
pages = {985-989},
doi = {10.1099/mic.0.000816},
pmid = {31140970},
issn = {1465-2080},
abstract = {Insects are frequently infected with inherited facultative symbionts known to provide a range of conditionally beneficial services, including host protection. Pea aphids (Acyrthosiphon pisum) often harbour the bacterium Hamiltonella defensa, which together with its associated bacteriophage A. pisum secondary endosymbiont (APSE) confer protection against an important natural enemy, the parasitic wasp Aphidius ervi. Previous studies showed that spontaneous loss of phage APSE resulted in the complete loss of the protective phenotype. Here, we demonstrate that APSEs can be experimentally transferred into phage-free (i.e. non-protecting) Hamiltonella strains. Unexpectedly, trials using injections of phage particles alone failed, with successful transfer occurring only when APSE and Hamiltonella were simultaneously injected. After transfer, stable establishment of APSE fully restored anti-parasitoid defenses. Thus, phages associated with heritable bacterial symbionts can move horizontally among symbiont strains facilitating the rapid transfer of ecologically important traits although natural barriers may preclude regular exchange.},
}
@article {pmid31139503,
year = {2019},
author = {Pochon, X and Wecker, P and Stat, M and Berteaux-Lecellier, V and Lecellier, G},
title = {Towards an in-depth characterization of Symbiodiniaceae in tropical giant clams via metabarcoding of pooled multi-gene amplicons.},
journal = {PeerJ},
volume = {7},
number = {},
pages = {e6898},
doi = {10.7717/peerj.6898},
pmid = {31139503},
issn = {2167-8359},
abstract = {High-throughput sequencing is revolutionizing our ability to comprehensively characterize free-living and symbiotic Symbiodiniaceae, a diverse dinoflagellate group that plays a critical role in coral reef ecosystems. Most studies however, focus on a single marker for metabarcoding Symbiodiniaceae, potentially missing important ecological traits that a combination of markers may capture. In this proof-of-concept study, we used a small set of symbiotic giant clam (Tridacna maxima) samples obtained from nine French Polynesian locations and tested a dual-index sequence library preparation method that pools and simultaneously sequences multiple Symbiodiniaceae gene amplicons per sample for in-depth biodiversity assessments. The rationale for this approach was to allow the metabarcoding of multiple genes without extra costs associated with additional single amplicon dual indexing and library preparations. Our results showed that the technique effectively recovered very similar proportions of sequence reads and dominant Symbiodiniaceae clades among the three pooled gene amplicons investigated per sample, and captured varying levels of phylogenetic resolution enabling a more comprehensive assessment of the diversity present. The pooled Symbiodiniaceae multi-gene metabarcoding approach described here is readily scalable, offering considerable analytical cost savings while providing sufficient phylogenetic information and sequence coverage.},
}
@article {pmid31139158,
year = {2019},
author = {Ahmed, HI and Herrera, M and Liew, YJ and Aranda, M},
title = {Long-Term Temperature Stress in the Coral Model Aiptasia Supports the &quot;Anna Karenina Principle&quot; for Bacterial Microbiomes.},
journal = {Frontiers in microbiology},
volume = {10},
number = {},
pages = {975},
doi = {10.3389/fmicb.2019.00975},
pmid = {31139158},
issn = {1664-302X},
abstract = {The understanding of host-microbial partnerships has become a hot topic during the last decade as it has been shown that associated microbiota play critical roles in the host physiological functions and susceptibility to diseases. Moreover, the microbiome may contribute to host resilience to environmental stressors. The sea anemone Aiptasia is a good laboratory model system to study corals and their microbial symbiosis. In this regard, studying its bacterial microbiota provides a better understanding of cnidarian metaorganisms as a whole. Here, we investigated the bacterial communities of different Aiptasia host-symbiont combinations under long-term heat stress in laboratory conditions. Following a 16S rRNA gene sequencing approach we were able to detect significant differences in the bacterial composition and structure of Aiptasia reared at different temperatures. A higher number of taxa (i.e., species richness), and consequently increased α-diversity and β-dispersion, were observed in the microbiomes of heat-stressed individuals across all host strains and experimental batches. Our findings are in line with the recently proposed Anna Karenina principle (AKP) for animal microbiomes, which states that dysbiotic or stressed organisms have a more variable and unstable microbiome than healthy ones. Microbial interactions affect the fitness and survival of their hosts, thus exploring the AKP effect on animal microbiomes is important to understand host resilience. Our data contributes to the current knowledge of the Aiptasia holobiont and to the growing field of study of host-associated microbiomes.},
}
@article {pmid31138619,
year = {2019},
author = {Saint-Leandre, B and Nguyen, SC and Levine, MT},
title = {Diversification and collapse of a telomere elongation mechanism.},
journal = {Genome research},
volume = {29},
number = {6},
pages = {920-931},
doi = {10.1101/gr.245001.118},
pmid = {31138619},
issn = {1549-5469},
support = {R00 GM107351/GM/NIGMS NIH HHS/United States ; R35 GM124684/GM/NIGMS NIH HHS/United States ; },
abstract = {In most eukaryotes, telomerase counteracts chromosome erosion by adding repetitive sequence to terminal ends. Drosophila melanogaster instead relies on specialized retrotransposons that insert exclusively at telomeres. This exchange of goods between host and mobile element-wherein the mobile element provides an essential genome service and the host provides a hospitable niche for mobile element propagation-has been called a &quot;genomic symbiosis.&quot; However, these telomere-specialized, jockey family retrotransposons may actually evolve to &quot;s