@article {pmid30538693,
year = {2018},
author = {George, F and Daniel, C and Thomas, M and Singer, E and Guilbaud, A and Tessier, FJ and Revol-Junelles, AM and Borges, F and Foligné, B},
title = {Occurrence and Dynamism of Lactic Acid Bacteria in Distinct Ecological Niches: A Multifaceted Functional Health Perspective.},
journal = {Frontiers in microbiology},
volume = {9},
number = {},
pages = {2899},
doi = {10.3389/fmicb.2018.02899},
pmid = {30538693},
issn = {1664-302X},
abstract = {Lactic acid bacteria (LAB) are representative members of multiple ecosystems on earth, displaying dynamic interactions within animal and plant kingdoms in respect with other microbes. This highly heterogeneous phylogenetic group has coevolved with plants, invertebrates, and vertebrates, establishing either mutualism, symbiosis, commensalism, or even parasitism-like behavior with their hosts. Depending on their location and environment conditions, LAB can be dominant or sometimes in minority within ecosystems. Whatever their origins and relative abundance in specific anatomic sites, LAB exhibit multifaceted ecological and functional properties. While some resident LAB permanently inhabit distinct animal mucosal cavities, others are provided by food and may transiently occupy the gastrointestinal tract. It is admitted that the overall gut microbiome has a deep impact on health and diseases. Here, we examined the presence and the physiological role of LAB in the healthy human and several animal microbiome. Moreover, we also highlighted some dysbiotic states and related consequences for health, considering both the resident and the so-called "transionts" microorganisms. Whether LAB-related health effects act collectively or follow a strain-specificity dogma is also addressed. Besides the highly suggested contribution of LAB to interplay with immune, metabolic, and even brain-axis regulation, the possible involvement of LAB in xenobiotic detoxification processes and metal equilibrium is also tackled. Recent technological developments such as functional metagenomics, metabolomics, high-content screening and design in vitro and in vivo experimental models now open new horizons for LAB as markers applied for disease diagnosis, susceptibility, and follow-up. Moreover, identification of general and more specific molecular mechanisms based on antioxidant, antimicrobial, anti-inflammatory, and detoxifying properties of LAB currently extends their selection and promising use, either as probiotics, in traditional and functional foods, for dedicated treatments and mostly for maintenance of normobiosis and homeostasis.},
}
@article {pmid30538687,
year = {2018},
author = {Paymaneh, Z and Gryndler, M and Konvalinková, T and Benada, O and Borovička, J and Bukovská, P and Püschel, D and Řezáčová, V and Sarcheshmehpour, M and Jansa, J},
title = {Soil Matrix Determines the Outcome of Interaction Between Mycorrhizal Symbiosis and Biochar for Andropogon gerardii Growth and Nutrition.},
journal = {Frontiers in microbiology},
volume = {9},
number = {},
pages = {2862},
doi = {10.3389/fmicb.2018.02862},
pmid = {30538687},
issn = {1664-302X},
abstract = {Biochar has been heralded as a multipurpose soil amendment to sustainably increase soil fertility and crop yields, affect soil hydraulic properties, reduce nutrient losses, and sequester carbon. Some of the most spectacular results of biochar (and organic nutrient) inputs are the terra preta soils in the Amazon, dark anthropogenic soils with extremely high fertility sustained over centuries. Such soil improvements have been particularly difficult to achieve on a short run, leading to speculations that biochar may need to age (weather) in soil to show its best. Further, interaction of biochar with arbuscular mycorrhizal fungi (AMF), important root symbionts of a great majority of terrestrial plants including most agricultural crops, remains little explored. To study the effect of aged biochar on highly mycotrophic Andropogon gerardii plants and their associated AMF, we made use of softwood biochar, collected from a historic charcoal burning site. This biochar (either untreated or chemically activated, the latter serving as a proxy for freshly prepared biochar) was added into two agricultural soils (acid or alkaline), and compared to soils without biochar. These treatments were further crossed with inoculation with a synthetic AMF community to address possible interactions between biochar and the AMF. Biochar application was generally detrimental for growth and mineral nutrition of our experimental plants, but had no effect on the extent of their root colonized by the AMF, nor did it affect composition of their root-borne AMF communities. In contrast, biochar affected development of two out of five AMF (Claroideoglomus and Funneliformis) in the soil. Establishment of symbiosis with AMF largely mitigated biochar-induced suppression of plant growth and mineral nutrition, mainly by improving plant acquisition of phosphorus. Both mycorrhizal and non-mycorrhizal plants grew well in the acid soil without biochar application, whereas non-mycorrhizal plants remained stunted in the alkaline soils under all situations (with or without biochar). These different and strong effects indicate that response of plants to biochar application are largely dependent on soil matrix and also on microbes such as AMF, and call for further research to enable qualified predictions of the effects of different biochar applications on field-grown crops and soil processes.},
}
@article {pmid30538275,
year = {2018},
author = {Nicolás, C and Martin-Bertelsen, T and Floudas, D and Bentzer, J and Smits, M and Johansson, T and Troein, C and Persson, P and Tunlid, A},
title = {The soil organic matter decomposition mechanisms in ectomycorrhizal fungi are tuned for liberating soil organic nitrogen.},
journal = {The ISME journal},
volume = {},
number = {},
pages = {},
doi = {10.1038/s41396-018-0331-6},
pmid = {30538275},
issn = {1751-7370},
support = {2013.0073//Knut och Alice Wallenbergs Stiftelse (Knut and Alice Wallenberg Foundation)/ ; },
abstract = {Many trees form ectomycorrhizal symbiosis with fungi. During symbiosis, the tree roots supply sugar to the fungi in exchange for nitrogen, and this process is critical for the nitrogen and carbon cycles in forest ecosystems. However, the extents to which ectomycorrhizal fungi can liberate nitrogen and modify the soil organic matter and the mechanisms by which they do so remain unclear since they have lost many enzymes for litter decomposition that were present in their free-living, saprotrophic ancestors. Using time-series spectroscopy and transcriptomics, we examined the ability of two ectomycorrhizal fungi from two independently evolved ectomycorrhizal lineages to mobilize soil organic nitrogen. Both species oxidized the organic matter and accessed the organic nitrogen. The expression of those events was controlled by the availability of glucose and inorganic nitrogen. Despite those similarities, the decomposition mechanisms, including the type of genes involved as well as the patterns of their expression, differed markedly between the two species. Our results suggest that in agreement with their diverse evolutionary origins, ectomycorrhizal fungi use different decomposition mechanisms to access organic nitrogen entrapped in soil organic matter. The timing and magnitude of the expression of the decomposition activity can be controlled by the below-ground nitrogen quality and the above-ground carbon supply.},
}
@article {pmid30538206,
year = {2018},
author = {Harding, K and Turk-Kubo, KA and Sipler, RE and Mills, MM and Bronk, DA and Zehr, JP},
title = {Symbiotic unicellular cyanobacteria fix nitrogen in the Arctic Ocean.},
journal = {Proceedings of the National Academy of Sciences of the United States of America},
volume = {},
number = {},
pages = {},
doi = {10.1073/pnas.1813658115},
pmid = {30538206},
issn = {1091-6490},
abstract = {Biological dinitrogen (N2) fixation is an important source of nitrogen (N) in low-latitude open oceans. The unusual N2-fixing unicellular cyanobacteria (UCYN-A)/haptophyte symbiosis has been found in an increasing number of unexpected environments, including northern waters of the Danish Straight and Bering and Chukchi Seas. We used nanoscale secondary ion mass spectrometry (nanoSIMS) to measure 15N2 uptake into UCYN-A/haptophyte symbiosis and found that UCYN-A strains identical to low-latitude strains are fixing N2 in the Bering and Chukchi Seas, at rates comparable to subtropical waters. These results show definitively that cyanobacterial N2 fixation is not constrained to subtropical waters, challenging paradigms and models of global N2 fixation. The Arctic is particularly sensitive to climate change, and N2 fixation may increase in Arctic waters under future climate scenarios.},
}
@article {pmid30384908,
year = {2018},
author = {Fan, M and Liu, Z and Nan, L and Wang, E and Chen, W and Lin, Y and Wei, G},
title = {Isolation, characterization, and selection of heavy metal-resistant and plant growth-promoting endophytic bacteria from root nodules of Robinia pseudoacacia in a Pb/Zn mining area.},
journal = {Microbiological research},
volume = {217},
number = {},
pages = {51-59},
doi = {10.1016/j.micres.2018.09.002},
pmid = {30384908},
issn = {1618-0623},
mesh = {Acclimatization ; Agrobacterium tumefaciens/drug effects/isolation & purification/metabolism ; Bacteria/classification/*drug effects/*isolation & purification/metabolism ; Biodegradation, Environmental ; Biomass ; Carbon-Carbon Lyases/metabolism ; DNA, Bacterial/analysis ; Endophytes/classification/*drug effects/*isolation & purification/metabolism ; Indoleacetic Acids/metabolism ; Lead/toxicity ; Mesorhizobium/drug effects/isolation & purification/metabolism ; Metals, Heavy/*toxicity ; Microbial Sensitivity Tests ; *Mining ; Phylogeny ; *Plant Development ; RNA, Ribosomal, 16S/genetics ; Rhizobium ; Robinia/growth & development/*microbiology ; Root Nodules, Plant/*microbiology ; Seedlings/growth & development ; Siderophores/metabolism ; Soil Microbiology ; Soil Pollutants/metabolism ; Symbiosis ; Zinc/toxicity ; },
abstract = {Multiple heavy metals (HMs) commonly coexist in mining areas, which highlights the necessity to select multiple HM-resistant plant growth-promoting bacteria for improving phytoremediation efficiency. In this study, we isolated and characterized 82 endophytic bacteria from the root nodules of black locust (Robinia pseudoacacia) grown in a Pb-Zn mining area. There were 80 isolates showing resistance to four HMs, 0.01-18.0 mM/L for Cd, 0.2-40.0 mM/L for Zn, 0.3-2.2 mM/L for Pb, and 0.2-1.4 mM/L for Cu. Indole-3-acetic acid production, siderophore production, and 1-aminocyclopropane-1-carboxylate deaminase activity were detected in 43, 50, and 17 isolates, respectively. Two symbiotic isolates selected with the highest potential for HM resistance and PGP traits, designated Mesorhizobium loti HZ76 and Agrobacterium radiobacter HZ6, were evaluated for promotion of plant growth and metal uptake by R. pseudoacacia seedlings grown in pots containing different levels of Cd, Zn, Pb, or Cu. HZ76 significantly increased plant shoot biomass, while HZ6 did not, compared with non-inoculated controls. The results indicate that inoculation with HZ76 or HZ6 relieved HM stress in the plants, depending on the type and concentration of HM in the treatment. Mesorhizobium loti HZ76 may be a better candidate for application in phytoremediation than A. radiobacter HZ6. The microsymbiosis between HM-resistant rhizobia and R. pseudoacacia is an interesting mutualistic system for phytoremediation in mining areas contaminated with multiple HMs.},
}
@article {pmid30384903,
year = {2018},
author = {Huang, X and Zhu, J and Cai, Z and Lao, Y and Jin, H and Yu, K and Zhang, B and Zhou, J},
title = {Profiles of quorum sensing (QS)-related sequences in phycospheric microorganisms during a marine dinoflagellate bloom, as determined by a metagenomic approach.},
journal = {Microbiological research},
volume = {217},
number = {},
pages = {1-13},
doi = {10.1016/j.micres.2018.08.015},
pmid = {30384903},
issn = {1618-0623},
mesh = {Acyltransferases/genetics/metabolism ; Bacteria/classification/*genetics/*metabolism ; Bacterial Physiological Phenomena ; Bacterial Proteins/genetics/metabolism ; Carbon-Sulfur Lyases/genetics/metabolism ; China ; Dinoflagellida/growth & development/*microbiology ; Eutrophication/physiology ; Marine Biology ; Metagenomics/*methods ; Microbiota/*genetics/*physiology ; Phylogeny ; Proteobacteria/genetics/metabolism ; Quorum Sensing/*genetics/*physiology ; RNA, Ribosomal, 16S/genetics ; Seawater/microbiology ; Sequence Analysis ; Sequence Analysis, Protein ; Sequence Homology ; Symbiosis ; Transcription Factors/genetics/metabolism ; },
abstract = {The complicated relationships among environmental microorganisms are regulated by quorum sensing (QS). Understanding QS-based signals could shed light on the interactions between microbial communities in certain environments. Although QS characteristics have been widely discussed, few studies have been conducted on the role of QS in phycospheric microorganisms. Here, we used metagenomics to examine the profile of AI-1 (AinS, HdtS, LuxI) and AI-2 (LuxS) autoinducers from a deeply sequenced microbial database, obtained from a complete dinoflagellate bloom. A total of 3001 putative AI-1 homologs and 130 AI-2 homologs were identified. The predominant member among the AI groups was HdtS. The abundance of HdtS, AinS, and LuxS increased as the bloom developed, whereas the abundance of LuxI showed the opposite trend. Phylogenetic analysis suggested that HdtS and LuxI synthase originated mainly from alpha-, beta-, and gamma-Proteobacteria, whereas AinS synthase originated solely from Vibrionales. In comparison to AI-1, the sequences related to AI-2 (LuxS) demonstrated a much wider taxonomic coverage. Some significant correlations were found between dominant species and QS signals. In addition to the QS, we also performed parallel analysis of the quorum quenching (QQ) sequences. In comparison to QS, the relative abundance of QQ signals was lower; however, an obvious frequency correlation was observed. These results suggested that QS and QQ signals co-participate in regulating microbial communities during an algal bloom. These data helped to reveal the characteristic behavior of algal symbiotic bacteria, and facilitated a better understanding of microbial dynamics during an algal bloom event from a chemical ecological perspective.},
}
@article {pmid29282064,
year = {2017},
author = {Gerardo, N and Hurst, G},
title = {Q&A: Friends (but sometimes foes) within: the complex evolutionary ecology of symbioses between host and microbes.},
journal = {BMC biology},
volume = {15},
number = {1},
pages = {126},
pmid = {29282064},
issn = {1741-7007},
mesh = {Animals ; *Biological Evolution ; Host-Pathogen Interactions/*physiology ; Microbiota/*physiology ; *Symbiosis ; },
abstract = {Over the past decade, there has been a pronounced shift in the study of host-microbe associations, with recognition that many of these associations are beneficial, and often critical, for a diverse array of hosts. There may also be pronounced benefits for the microbes, though this is less well empirically understood. Significant progress has been made in understanding how ecology and evolution shape simple associations between hosts and one or a few microbial species, and this work can serve as a foundation to study the ecology and evolution of host associations with their often complex microbial communities (microbiomes).},
}
@article {pmid29173838,
year = {2017},
author = {Martino, ME and Leulier, F},
title = {Guest editorial: Microbiota: Microbiota and animal ecology, evolution and physiology: back to the future.},
journal = {Current opinion in microbiology},
volume = {38},
number = {},
pages = {viii-x},
doi = {10.1016/j.mib.2017.09.017},
pmid = {29173838},
issn = {1879-0364},
mesh = {Animals ; Bacteria/metabolism ; *Bacterial Physiological Phenomena ; *Biological Evolution ; Caenorhabditis elegans/metabolism/microbiology ; Drosophila melanogaster/metabolism/microbiology ; *Environmental Microbiology ; Gastrointestinal Microbiome/genetics/*physiology ; Host Microbial Interactions/genetics/*physiology ; Humans ; Plants/metabolism/microbiology ; Symbiosis ; },
}
@article {pmid30536933,
year = {2018},
author = {Brown, A and Akçay, E},
title = {Evolution of transmission mode in conditional mutualisms with spatial variation in symbiont quality.},
journal = {Evolution; international journal of organic evolution},
volume = {},
number = {},
pages = {},
doi = {10.1111/evo.13656},
pmid = {30536933},
issn = {1558-5646},
abstract = {Many symbioses have costs and benefits to their hosts that vary with the environmental context, which itself may vary in space. The same symbiont may be a mutualist in one location and a parasite in another. Such spatially conditional mutualisms pose a dilemma for hosts, who might evolve (higher or lower) horizontal or vertical transmission to increase their chances of being infected only where the symbiont is beneficial. To determine how transmission in hosts might evolve, we modeled transmission evolution where the symbiont had a spatially conditional effect on either host lifespan or fecundity. We found that over ecological time, symbionts that affected lifespan but not fecundity led to high frequencies of infected hosts in areas where the symbiont was beneficial and low frequencies elsewhere. In response, hosts evolved increased horizontal transmission only when the symbiont affected lifespan. We also modeled transmission evolution in symbionts, which evolved high horizontal and vertical transmission, indicating a possible host-symbiont conflict over transmission mode. Our results suggest an eco-evolutionary feedback where the component of host fitness affected by a conditionally mutualistic symbiont in turn determines its distribution in the population, and, through this, the transmission mode that evolves. This article is protected by copyright. All rights reserved.},
}
@article {pmid30535938,
year = {2018},
author = {Tullio, LD and Nakatani, AS and Gomes, DF and Ollero, FJ and Megías, M and Hungria, M},
title = {Revealing the roles of y4wF and tidC genes in Rhizobium tropici CIAT 899: biosynthesis of indolic compounds and impact on symbiotic properties.},
journal = {Archives of microbiology},
volume = {},
number = {},
pages = {},
doi = {10.1007/s00203-018-1607-y},
pmid = {30535938},
issn = {1432-072X},
support = {CNPq 465133/2014-2, Fundação Araucária-STI, CAPES//INCT-Plant-Growth Promoting Microorganisms for Agricultural Sustainability and Environmental Responsibility/ ; 02.13.08.001.00.00//Empresa Brasileira de Pesquisa Agropecuária/ ; 400468/2016-6//Conselho Nacional de Desenvolvimento Científico e Tecnológico/ ; MINECO, AGL2016-77163-R//Ministerio de Economía, Industria y Competitividad, Gobierno de España/ ; },
abstract = {Rhizobium tropici CIAT 899 is a strain known by its ability to nodulate a broad range of legume species, to synthesize a variety of Nod factors, its tolerance of abiotic stresses, and its high capacity to fix atmospheric N2, especially in symbiosis with common bean (Phaseolus vulgaris L.). Genes putatively related to the synthesis of indole acetic acid (IAA) have been found in the symbiotic plasmid of CIAT 899, in the vicinity of the regulatory nodulation gene nodD5, and, in this study, we obtained mutants for two of these genes, y4wF and tidC (R. tropici indole-3-pyruvic acid decarboxylase), and investigated their expression in the absence and presence of tryptophan (TRP) and apigenin (API). In general, mutations of both genes increased exopolysaccharide (EPS) synthesis and did not affect swimming or surface motility; mutations also delayed nodule formation, but increased competitiveness. We found that the indole-3-acetamide (IAM) pathway was active in CIAT 899 and not affected by the mutations, and-noteworthy-that API was required to activate the tryptamine (TAM) and the indol-3-pyruvic acid (IPyA) pathways in all strains, particularly in the mutants. High up-regulation of y4wF and tidC genes was observed in both the wild-type and the mutant strains in the presence of API. The results obtained revealed an intriguing relationship between IAA metabolism and nod-gene-inducing activity in R. tropici CIAT 899. We discuss the IAA pathways, and, based on our results, we attribute functions to the y4wF and tidC genes of R. tropici.},
}
@article {pmid30535374,
year = {2018},
author = {Chang, Y and Liu, H and Liu, M and Liao, X and Sahu, SK and Fu, Y and Song, B and Cheng, S and Kariba, R and Muthemba, S and Hendre, PS and Mayes, S and Ho, WK and Kendabie, P and Wang, S and Li, L and Muchugi, A and Jamnadass, R and Lu, H and Peng, S and Van Deynze, A and Simons, A and Yana-Shapiro, H and Xu, X and Yang, H and Wang, J and Liu, X},
title = {The draft genomes of five agriculturally important African orphan crops.},
journal = {GigaScience},
volume = {},
number = {},
pages = {},
doi = {10.1093/gigascience/giy152},
pmid = {30535374},
issn = {2047-217X},
abstract = {Background: Continuous growth of the world population is expected to double the worldwide demand for food by 2050. Eighty-eight percent of countries current face a serious burden of malnutrition, especially in Africa and South and South-East Asia. About 95% of the food energy needs of humans are fulfilled by just 30 species, of which wheat, maize and rice provide the majority of calories. Therefore, to diversify and stabilize global food supply, enhance agricultural productivity and tackle malnutrition, greater use of neglected or underutilized local plants (so-called &quot;orphan crops,&quot; but also including a few plants of special significance to agriculture, agroforestry and nutrition) could be a partial solution.<br><br>Results: Here, we present draft genome information from five agriculturally, biologically, medicinally and economically important underutilized plants native to Africa; Vigna subterranea, Lablab purpureus, Faidherbia albida, Sclerocarya birrea, and Moringa oleifera. Assembled genomes range in size from 217 to 654 Mb. In V. subterranea, L. purpureus, F. albida, S. birrea and M. oleifera we have predicted 31707, 20946, 28979, 18937, 18451 protein-coding genes, respectively. By further analysing the expansion and contraction of selected gene families, we have characterized root nodule symbiosis genes, transcription factors and starch biosynthesis-related genes in these genomes.<br><br>Conclusions: These genome data will be useful to identify and characterize agronomically important genes and understand their modes of action, enabling genomics-based, evolutionary studies, and breeding strategies to design faster, more focused and predictable crop improvement programs.},
}
@article {pmid30534962,
year = {2018},
author = {Gutiérrez-García, K and Bustos-Díaz, ED and Corona-Gómez, JA and Ramos-Aboites, HE and Sélem-Mojica, N and Cruz-Morales, P and Pérez-Farrera, MA and Barona-Gómez, F and Cibrián-Jaramillo, A},
title = {Cycad coralloid roots contain bacterial communities including cyanobacteria and Caulobacter spp that encode niche-specific biosynthetic gene clusters.},
journal = {Genome biology and evolution},
volume = {},
number = {},
pages = {},
doi = {10.1093/gbe/evy266},
pmid = {30534962},
issn = {1759-6653},
abstract = {Cycads are the only early seed plants that have evolved a specialized root to host endophytic bacteria that fix nitrogen. To provide evolutionary and functional insights into this million-year old symbiosis, we investigate endophytic bacterial sub-communities isolated from coralloid roots of species from Dioon (Zamiaceae) sampled from their natural habitats. We employed a sub-community co-culture experimental strategy to reveal both predominant and rare bacteria, which were characterized using phylogenomics and detailed metabolic annotation. Diazotrophic plant endophytes, including Bradyrhizobium, Burkholderia, Mesorhizobium, Rhizobium and Nostoc species, dominated the epiphyte-free sub-communities. Draft genomes of six cyanobacteria species were obtained after shotgun metagenomics of selected sub-communities. This data was used for whole-genome inferences that suggest two Dioon-specific monophyletic groups, and a level of specialization characteristic of co-evolved symbiotic relationships. Furthermore, the genomes of these cyanobacteria were found to encode unique biosynthetic gene clusters, predicted to direct the synthesis of specialized metabolites, mainly involving peptides. After combining genome mining with detection of pigment emissions using multiphoton excitation fluorescence microscopy, we also show that Caulobacter species co-exist with cyanobacteria, and may interact with them by means of a novel indigoidine-like specialized metabolite. We provide an unprecedented view of the composition of the cycad coralloid root, including phylogenetic and functional patterns mediated by specialized metabolites that may be important for the evolution of ancient symbiotic adaptations.},
}
@article {pmid30534351,
year = {2018},
author = {Liang, J and Hoffrichter, A and Brachmann, A and Marín, M},
title = {Complete genome of Rhizobium leguminosarum Norway, an ineffective Lotus micro-symbiont.},
journal = {Standards in genomic sciences},
volume = {13},
number = {},
pages = {36},
doi = {10.1186/s40793-018-0336-9},
pmid = {30534351},
issn = {1944-3277},
abstract = {Rhizobia bacteria engage in nitrogen-fixing root nodule symbiosis, a mutualistic interaction with legume plants in which a bidirectional nutrient exchange takes place. Occasionally, this interaction is suboptimal resulting in the formation of ineffective nodules in which little or no atmospheric nitrogen fixation occurs. Rhizobium leguminosarum Norway induces ineffective nodules in a wide range of Lotus hosts. To investigate the basis of this phenotype, we sequenced the complete genome of Rl Norway and compared it to the genome of the closely related strain R. leguminosarum bv. viciae 3841. The genome comprises 7,788,085 bp, distributed on a circular chromosome containing 63% of the genomic information and five large circular plasmids. The functionally classified bacterial gene set is distributed evenly among all replicons. All symbiotic genes (nod, fix, nif) are located on the pRLN3 plasmid. Whole genome comparisons revealed differences in the metabolic repertoire and in protein secretion systems, but not in classical symbiotic genes.},
}
@article {pmid30533911,
year = {2018},
author = {Montecillo, AD and Raymundo, AK and Papa, IA and Aquino, GMB and Rosana, ARR},
title = {Complete Genome Sequence of Rhizobium sp. Strain 11515TR, Isolated from Tomato Rhizosphere in the Philippines.},
journal = {Microbiology resource announcements},
volume = {7},
number = {7},
pages = {},
doi = {10.1128/MRA.00903-18},
pmid = {30533911},
issn = {2576-098X},
abstract = {Rhizobium sp. strain 11515TR was isolated from the rhizosphere of tomato in Laguna, Philippines. The 7.07-Mb complete genome comprises three replicons, one chromosome, and two plasmids, with a G+C content of 59.4% and 6,720 protein-coding genes. The genome encodes gene clusters supporting rhizosphere processes, plant symbiosis, and secondary bioactive metabolites.},
}
@article {pmid30533842,
year = {2018},
author = {Nguyen, HDT and Cloutier, S and Bromfield, ESP},
title = {Complete Genome Sequence of Bradyrhizobium ottawaense OO99T, an Efficient Nitrogen-Fixing Symbiont of Soybean.},
journal = {Microbiology resource announcements},
volume = {7},
number = {21},
pages = {},
doi = {10.1128/MRA.01477-18},
pmid = {30533842},
issn = {2576-098X},
abstract = {We present the complete genome sequence of Bradyrhizobium ottawaense strain OO99T, a nitrogen-fixing bacterium from root nodules of soybean. The genome consists of a single 8.6-Mb chromosome and includes a symbiosis island. Genes involved in symbiotic nitrogen fixation, stress response, resistance to antibiotics, and toxic compounds were detected.},
}
@article {pmid30533769,
year = {2018},
author = {Andryuschenko, SV and Ivanova, EV and Perunova, NB and Zdvizhkova, IA and Bekpergenova, AV and Bukharin, OV},
title = {Draft Genome Sequence of Bifidobacterium bifidum Strain ICIS-310, Isolated from the Feces of a Healthy 5-Year-Old Child from Orenburg, Russia.},
journal = {Microbiology resource announcements},
volume = {7},
number = {18},
pages = {},
doi = {10.1128/MRA.01271-18},
pmid = {30533769},
issn = {2576-098X},
abstract = {This report describes the draft genome sequence of Bifidobacterium bifidum strain ICIS-310, isolated from the feces of a healthy 5-year-old child from Orenburg, Russia. The size of the genome was 2,219,632 bp (62.4% G+C content). Annotation revealed 1,886 coding sequences, including 1,718 proteins, 6 rRNA genes, and 52 tRNA genes.},
}
@article {pmid30533398,
year = {2018},
author = {Brock, DA and Haselkorn, TS and Garcia, JR and Bashir, U and Douglas, TE and Galloway, J and Brodie, F and Queller, DC and Strassmann, JE},
title = {Diversity of Free-Living Environmental Bacteria and Their Interactions With a Bactivorous Amoeba.},
journal = {Frontiers in cellular and infection microbiology},
volume = {8},
number = {},
pages = {411},
doi = {10.3389/fcimb.2018.00411},
pmid = {30533398},
issn = {2235-2988},
abstract = {A small subset of bacteria in soil interact directly with eukaryotes. Which ones do so can reveal what is important to a eukaryote and how eukaryote defenses might be breached. Soil amoebae are simple eukaryotic organisms and as such could be particularly good for understanding how eukaryote microbiomes originate and are maintained. One such amoeba, Dictyostelium discoideum, has both permanent and temporary associations with bacteria. Here we focus on culturable bacterial associates in order to interrogate their relationship with D. discoideum. To do this, we isolated over 250 D. discoideum fruiting body samples from soil and deer feces at Mountain Lake Biological Station. In one-third of the wild D. discoideum we tested, one to six bacterial species were found per fruiting body sorus (spore mass) for a total of 174 bacterial isolates. The remaining two-thirds of D. discoideum fruiting body samples did not contain culturable bacteria, as is thought to be the norm. A majority (71.4%) of the unique bacterial haplotypes are in Proteobacteria. The rest are in either Actinobacteria, Bacteriodetes, or Firmicutes. The highest bacterial diversity was found in D. discoideum fruiting bodies originating from deer feces (27 OTUs), greater than either of those originating in shallow (11 OTUs) or in deep soil (4 OTUs). Rarefaction curves and the Chao1 estimator for species richness indicated the diversity in any substrate was not fully sampled, but for soil it came close. A majority of the D. discoideum-associated bacteria were edible by D. discoideum and supported its growth (75.2% for feces and 81.8% for soil habitats). However, we found several bacteria genera were able to evade phagocytosis and persist in D. discoideum cells through one or more social cycles. This study focuses not on the entire D. discoideum microbiome, but on the culturable subset of bacteria that have important eukaryote interactions as prey, symbionts, or pathogens. These eukaryote and bacteria interactions may provide fertile ground for investigations of bacteria using amoebas to gain an initial foothold in eukaryotes and of the origins of symbiosis and simple microbiomes.},
}
@article {pmid30533318,
year = {2018},
author = {Kenkel, CD and Bay, LK},
title = {Exploring mechanisms that affect coral cooperation: symbiont transmission mode, cell density and community composition.},
journal = {PeerJ},
volume = {6},
number = {},
pages = {e6047},
doi = {10.7717/peerj.6047},
pmid = {30533318},
issn = {2167-8359},
abstract = {The coral symbiosis is the linchpin of the reef ecosystem, yet the mechanisms that promote and maintain cooperation between hosts and symbionts have not been fully resolved. We used a phylogenetically controlled design to investigate the role of vertical symbiont transmission, an evolutionary mechanism in which symbionts are inherited directly from parents, predicted to enhance cooperation and holobiont fitness. Six species of coral, three vertical transmitters and their closest horizontally transmitting relatives, which exhibit environmental acquisition of symbionts, were fragmented and subjected to a 2-week thermal stress experiment. Symbiont cell density, photosynthetic function and translocation of photosynthetically fixed carbon between symbionts and hosts were quantified to assess changes in physiological performance and cooperation. All species exhibited similar decreases in symbiont cell density and net photosynthesis in response to elevated temperature, consistent with the onset of bleaching. Yet baseline cooperation, or translocation of photosynthate, in ambient conditions and the reduction in cooperation in response to elevated temperature differed among species. Although Porites lobata and Galaxea acrhelia did exhibit the highest levels of baseline cooperation, we did not observe universally higher levels of cooperation in vertically transmitting species. Post hoc sequencing of the Symbiodinium ITS-2 locus was used to investigate the potential role of differences in symbiont community composition. Interestingly, reductions in cooperation at the onset of bleaching tended to be associated with increased symbiont community diversity among coral species. The theoretical benefits of evolving vertical transmission are based on the underlying assumption that the host-symbiont relationship becomes genetically uniform, thereby reducing competition among symbionts. Taken together, our results suggest that it may not be vertical transmission per se that influences host-symbiont cooperation, but genetic uniformity of the symbiont community, although additional work is needed to test this hypothesis.},
}
@article {pmid30533314,
year = {2018},
author = {Kariman, K and Barker, SJ and Tibbett, M},
title = {Structural plasticity in root-fungal symbioses: diverse interactions lead to improved plant fitness.},
journal = {PeerJ},
volume = {6},
number = {},
pages = {e6030},
doi = {10.7717/peerj.6030},
pmid = {30533314},
issn = {2167-8359},
abstract = {Root-fungal symbioses such as mycorrhizas and endophytes are key components of terrestrial ecosystems. Diverse in trophy habits (obligate, facultative or hemi-biotrophs) and symbiotic relations (from mutualism to parasitism), these associations also show great variability in their root colonization and nutritional strategies. Specialized interface structures such as arbuscules and Hartig nets are formed by certain associations while others are restricted to non-specialized intercellular or intracellular hyphae in roots. In either case, there are documented examples of active nutrient exchange, reinforcing the fact that specialized structures used to define specific mycorrhizal associations are not essential for reciprocal exchange of nutrients and plant growth promotion. In feremycorrhiza (with Austroboletus occidentalis and eucalypts), the fungal partner markedly enhances plant growth and nutrient acquisition without colonizing roots, emphasizing that a conventional focus on structural form of associations may have resulted in important functional components of rhizospheres being overlooked. In support of this viewpoint, mycobiome studies using the state-of-the-art DNA sequencing technologies have unearthed much more complexity in root-fungal relationships than those discovered using the traditional morphology-based approaches. In this review, we explore the existing literature and most recent findings surrounding structure, functioning, and ecology of root-fungal symbiosis, which highlight the fact that plant fitness can be altered by taxonomically/ecologically diverse fungal symbionts regardless of root colonization and interface specialization. Furthermore, transition from saprotrophy to biotrophy seems to be a common event that occurs in diverse fungal lineages (consisting of root endophytes, soil saprotrophs, wood decayers etc.), and which may be accompanied by development of specialized interface structures and/or mycorrhiza-like effects on plant growth and nutrition.},
}
@article {pmid30533255,
year = {2018},
author = {Koné, NA and Soro, B and Vanié-Léabo, LPL and Konaté, S and Bakayoko, A and Koné, D},
title = {Diversity, phenology and distribution of Termitomyces species in Côte d'Ivoire.},
journal = {Mycology},
volume = {9},
number = {4},
pages = {307-315},
doi = {10.1080/21501203.2018.1500498},
pmid = {30533255},
issn = {2150-1203},
abstract = {The mutualistic symbiosis between termites of the Macrotermitinae subfamily (Isoptera: Termitidae) and fungi of the genus Termitomyces (Basidiomycota: Lyophyllaceae) is of great ecological and socio-economic importance. Seasonal fruit bodies of the symbiotic fungi are regularly collected and sold in Côte d'Ivoire. However, there are very few studies on their diversity, phenology, distribution and especially the socio-economic scope of the fruit bodies of these fungi at a national scale. This study aims at (i) assessing the diversity of Termitomyces fruit bodies in Côte d'Ivoire and (ii) mapping their fructification areas through a determination of their spatiotemporal distribution according to a climatic and phytogeographic gradients. Using ethnomycological surveys all over the Ivorian territory, information was collected from rural populations on the fructification of Termitomyces and their socio-economic importance. Based on these surveys, sampling efforts of these fungi were properly structured and oriented. The results revealed a diversity of 16 species of Termitomyces, including 9 species new to Côte d'Ivoire and 2 probably new to science. Five species were found in the forest zone, nine in theGuinean savannah zone and four in the Sudano-Guinean zone. Termitomyces's fructifications were observed throughout the year, with specific period for each species. All listed species are regularly consumed by populations. However, only Termitomyces letestui (Pat.) R. Heim and Termitomyces schimperi (Pat.) R. Heim are marketed on a relatively large scale.},
}
@article {pmid30530738,
year = {2018},
author = {Newman-Griffis, AH and Del Cerro, P and Charpentier, M and Meier, I},
title = {Medicago LINC complexes function in nuclear morphology, nuclear movement, and root nodule symbiosis.},
journal = {Plant physiology},
volume = {},
number = {},
pages = {},
doi = {10.1104/pp.18.01111},
pmid = {30530738},
issn = {1532-2548},
abstract = {Nuclear movement is involved in cellular and developmental processes across eukaryotic life, often driven by Linker of Nucleoskeleton and Cytoskeleton (LINC) complexes, which bridge the nuclear envelope (NE) via the interaction of Klarsicht/ANC-1/Syne-1 Homology (KASH) and Sad1/UNC-84 (SUN) proteins. Arabidopsis (Arabidopsis thaliana) LINC complexes are involved in nuclear movement and positioning in several cell types. Observations since the 1950s have described targeted nuclear movement and positioning during symbiosis initiation between legumes and rhizobia, but it has never been established whether these movements are functional or incidental. Here, we identify and characterize LINC complexes in the model legume Medicago truncatula. We show that LINC complex characteristics such as NE localization, dependence of KASH proteins on SUN protein binding for NE enrichment, and direct SUN-KASH binding are conserved between plant species. Using a SUN dominant-negative strategy, we demonstrate that LINC complexes are necessary for proper nuclear shaping and movement in Medicago root hairs, and are important for infection thread initiation and nodulation.},
}
@article {pmid30530198,
year = {2018},
author = {Hu, D and Baskin, JM and Baskin, CC and Wang, Z and Zhang, S and Yang, X and Huang, Z},
title = {Arbuscular mycorrhizal symbiosis and achene mucilage have independent functions in seedling growth of a desert shrub.},
journal = {Journal of plant physiology},
volume = {232},
number = {},
pages = {1-11},
doi = {10.1016/j.jplph.2018.11.010},
pmid = {30530198},
issn = {1618-1328},
abstract = {Arbuscular mycorrhizal (AM) symbiosis can play a role in improving seedling establishment in deserts, and it has been suggested that achene mucilage facilitates seedling establishment in sandy deserts and that mucilage biodegradation products may improve seedling growth. We aimed to determine if AM symbiosis interacts with achene mucilage in regulating seedling growth in sand dunes. Up to 20 A M fungal taxa colonized Artemisia sphaerocephala roots in the field, and mycorrhizal frequency and colonization intensity exhibited seasonal dynamics. In the greenhouse, total biomass of AM fungal-colonized plants decreased, whereas the root/shoot ratio increased. AM symbiosis resulted in increased concentrations of nutrients and chlorophyll and decreased concentrations of salicylic acid (SA) and abscisic acid (ABA). Achene mucilage had a weaker effect on biomass and on nutrient, chlorophyll, and phytohormone concentration than did AM symbiosis. We suggest that AM symbiosis and achene mucilage act independently in enhancing seedling establishment in sandy deserts.},
}
@article {pmid30527539,
year = {2018},
author = {Hanachi, M and Manichanh, C and Schoenenberger, A and Pascal, V and Levenez, F and Cournède, N and Doré, J and Melchior, JC},
title = {Altered host-gut microbes symbiosis in severely malnourished anorexia nervosa (AN) patients undergoing enteral nutrition: An explicative factor of functional intestinal disorders?.},
journal = {Clinical nutrition (Edinburgh, Scotland)},
volume = {},
number = {},
pages = {},
doi = {10.1016/j.clnu.2018.10.004},
pmid = {30527539},
issn = {1532-1983},
abstract = {BACKGROUND: Functional intestinal disorders (FIDs) are frequently observed in patients with anorexia nervosa (AN). Relationship between FIDs and a potential gut microbiota dysbiosis has been poorly explored.<br><br>OBJECTIVE: We aimed to determine an association between FIDs severity and dysbiosis of the intestinal microbiota in a severely malnourished patient population with AN undergoing enteral nutrition.<br><br>DESIGN: Faecal microbiota of AN (DSM IVr criteria) female inpatients were collected and compared to healthy controls based on 16S rRNA profiling. The severity of FIDs was evaluated in patients and healthy controls using Francis Score.<br><br>RESULTS: Thirty-three patients (BMI: 11,7 ± 1,5; Age: 32 ± 12) and 22 healthy controls (BMI: 21 ± 2; age: 36 ± 12) were included. A marked dysbiosis was identified in AN patients compared to healthy controls (p = 0.03). Some potentially pathogenic bacterial genera (Klebsiella, Salmonella) were more abundant in AN patients whereas, other bacterial symbionts (Eubacterium and Roseburia) involved in immune balance were significantly less abundant in patients than controls. Severity of FIDs was strongly correlated with several microbial genera (r = -0.581 for an unknown genus belonging to Peptostreptococcaceae family; r = 0.392 for Dialister, r = 0.444 for Robinsoniella and r = 0.488 for Enterococcus). Other associations between dysbiosis, clinical and biological characteristics were identified including severity of undernutrition (BMI).<br><br>CONCLUSION: Observed gut microbiota dysbiosis in malnourished patients with anorexia nervosa is correlated with the severity of FIDs and other metabolic disturbances, which strongly suggests an altered host-microbe symbiosis.},
}
@article {pmid30311875,
year = {2018},
author = {Barelli, L and Moreira, CC and Bidochka, MJ},
title = {Initial stages of endophytic colonization by Metarhizium involves rhizoplane colonization.},
journal = {Microbiology (Reading, England)},
volume = {164},
number = {12},
pages = {1531-1540},
doi = {10.1099/mic.0.000729},
pmid = {30311875},
issn = {1465-2080},
abstract = {Here we assessed the time course of rhizoplane colonization by the endophytic insect pathogenic fungus Metarhizium robertsii. We describe a method of quantifying root colonization of bean plants by M. robertsii using quantitative polymerase chain reaction (qPCR). Results of this method were compared to the standard plate count method using colony-forming units (c.f.u.). Both the c.f.u. and qPCR methods were used to monitor the time-course of haricot bean (Phaseolus vulgaris) colonization by a strain of M. robertsii that expresses the green fluorescent protein (ARSEF 2575-GFP) for colony verification. There was a strong correlation between the results of the c.f.u. and qPCR methods, indicating that both methods are well suited for the determination of colonization of P. vulgaris roots by M. robertsii. Primers for a catalase gene (cat) amplified DNA from M. robertsii, M. brunneum and M. guizhouense. Primers for a nitrogen response-regulator (nrr) additionally detected M. acridum and M. flavoviride, whereas Metarhizium perilipin-like protein (mpl) primers were specific to M. robertsii alone. However, cat was the only target that specifically amplified Metarhizium in experiments utilizing non-sterile soil. Endophytic colonization of P. vulgaris at 60 days post-inoculation with M. robertsii was detected from surface-sterilized roots with more sensitivity using our qPCR technique over the c.f.u. method. Our results suggest that there is a prolonged period of rhizoplane colonization by Metarhizium with transient, low-level endophytic colonization of the root system of P. vulgaris that persists for the entirety of the plant life cycle.},
}
@article {pmid30291510,
year = {2018},
author = {Inagaki, T and Matsuura, K},
title = {Extended mutualism between termites and gut microbes: nutritional symbionts contribute to nest hygiene.},
journal = {Die Naturwissenschaften},
volume = {105},
number = {9-10},
pages = {52},
pmid = {30291510},
issn = {1432-1904},
support = {25221206//Japan Society for the Promotion of Science/ ; },
mesh = {Animal Nutritional Physiological Phenomena ; Animals ; *Bacterial Physiological Phenomena ; Gastrointestinal Tract/microbiology ; Isoptera/*microbiology ; *Symbiosis ; },
abstract = {All higher eukaryotes have established symbiotic relationships with diverse microorganisms. One of the most well-characterized symbiotic systems is that of termites and their intestinal microorganisms, which digest cellulose. Recently, diverse types of symbioses between gut microbes and host organisms including humans have received growing attention for various features of their complex interactions beyond nutrition. In termites, researchers are beginning to explore such function of gut symbionts, but only the contribution to internal immunity against entomopathogen is known in a few species. Here, we report that gut symbionts of the dampwood termite Zootermopsis nevadensis protect nests from the spread of the commensal bacterium Serratia marcescens, which has pathogenic potential. Defaunated termites dispersed S. marcescens in the surrounding environment by feeding on the bacteria, which then survived passage through their alimentary tracts, while non-defaunated termites did not. Loss of gut symbionts caused a significant reduction in intestinal acetate, which is an important carbon source for termites. Culture experiments showed that acetate had significant inhibitory effects on S. marcescens at a concentration as low as 12 mM, which indicated that the intestinal acetate of non-defaunated termites (40-130 mM) was capable of suppressing this bacterium. These results suggest that digestive derivatives produced by intestinal symbionts play an essential role in nest hygiene in addition to their nutritional function for termites. Our study provides a better understanding of the multifunctionality of symbiotic relationships in diverse organisms beyond nutrition.},
}
@article {pmid30193163,
year = {2018},
author = {Lei, YJ and Tian, Y and Zhang, J and Sun, L and Kong, XW and Zuo, W and Kong, LC},
title = {Microalgae cultivation and nutrients removal from sewage sludge after ozonizing in algal-bacteria system.},
journal = {Ecotoxicology and environmental safety},
volume = {165},
number = {},
pages = {107-114},
doi = {10.1016/j.ecoenv.2018.08.096},
pmid = {30193163},
issn = {1090-2414},
mesh = {Ammonium Compounds/analysis ; Bacteria/*growth &amp; development ; *Biomass ; Bioreactors/*microbiology ; Microalgae/*growth &amp; development ; Nitrogen/analysis ; Oxygen/metabolism ; Ozone ; Phosphorus/analysis ; Sewage/*chemistry/microbiology ; Symbiosis ; Waste Disposal, Fluid/methods ; },
abstract = {The feasibility of growing algae in concentrated wastewater generated from sludge ozonation for simultaneous nutrients removal and biomass production was studied. The effects of bacteria addition into microalgae on nutrients removal, biomass yield and settleability, the growth rate of algae and concentrations of extracellular polymeric substances (EPS) and soluble microbial products (SMP) were investigated. The results showed that the growth rate of algae in algal-bacteria system (0.2182) was improved than in algae-only system (0.1852), while both of them are comparable with others reported previously. And the addition of bacteria enhanced COD, NH4+-N, TN and TP removal rate by 23.9 ± 3.3%, 27.7 ± 3.6%, 16.6 ± 1.8% and 14.9 ± 2.2%, respectively. And 32.8 ± 0.7% of the TN and 50.3 ± 1.8% of the TP were recycled from ozonated sludge-supernatant (OSS) being absorbed into algal-bacterial biomass. The algal-bacteria system also demonstrated advantages on biomass settleability and heavy metals removal. Finally, the mechanism involving matter exchange and algal-bacteria system on OSS treatment in this study were discussed through evaluation of nutrients, SMP and EPS contents, nitrogen and phosphorus balance.},
}
@article {pmid30150426,
year = {2018},
author = {Kostaropoulos, T and Papageorgiou, L and Champeris Tsaniras, S and Vlachakis, D and Eliopoulos, E},
title = {Carcinogenic Pesticide Control via Hijacking Endosymbiosis; The Paradigm of DSB-A from Wolbachia pipientis for the Management of Otiorhynchus singularis.},
journal = {In vivo (Athens, Greece)},
volume = {32},
number = {5},
pages = {1051-1062},
pmid = {30150426},
issn = {1791-7549},
mesh = {Amino Acid Motifs ; Amino Acid Sequence ; Animals ; *Carcinogens/toxicity ; *Chemical Safety ; Coleoptera/*microbiology ; Conserved Sequence ; Drug Design ; *Insect Control ; Models, Molecular ; *Pesticides/adverse effects ; Phylogeny ; Protein Conformation ; Protein Disulfide-Isomerases/chemistry/classification/genetics/*metabolism ; Structure-Activity Relationship ; *Symbiosis ; Wolbachia/enzymology/genetics/*metabolism ; },
abstract = {BACKGROUND/AIM: Pesticides have little, if any specificity, to the pathogen they target in most cases. Wide spectrum toxic chemicals are being used to remove pestcides and salvage crops and economies linked to agriculture. The burden on the environment, public health and economy is huge. Traditional pestcide control is based on administering heavy loads of highly toxic compounds and elements that essentially strip all life from the field. Those chemicals are a leading cause of increased cancer related deaths in countryside. Herein, the Trojan horse of endosymbiosis was used, in an effort to control pests using high specificity compounds in reduced quantities.<br><br>MATERIALS AND METHODS: Our pipeline has been applied on the case of Otiorhynchus singularis, which is a very widespread pest, whose impact is devastating on a repertoire of crops. To date, there is no specific pesticide nor agent to control it. The deployed strategy involves the inhibition of the key DSB-A enzyme of its endosymbiotic Wolbachia pipientis bacterial strain.<br><br>RESULTS: Our methodology, provides the means to design, test and identify highly specific pestcide control substances that minimize the impact of toxic chemicals on health, economy and the environment.<br><br>CONCLUSION: All in all, in this study a radical computer-based pipeline is proposed that could be adopted under many other similar scenarios and pave the way for precision agriculture via optimized pest control.},
}
@article {pmid30142922,
year = {2018},
author = {Stabili, L and Parisi, MG and Parrinello, D and Cammarata, M},
title = {Cnidarian Interaction with Microbial Communities: From Aid to Animal's Health to Rejection Responses.},
journal = {Marine drugs},
volume = {16},
number = {9},
pages = {},
pmid = {30142922},
issn = {1660-3397},
mesh = {Animals ; Biotechnology/methods ; Cnidaria/microbiology/*physiology ; Homeostasis/immunology ; *Immunity, Innate ; Microbiota/*immunology ; Mucous Membrane/immunology/microbiology ; Phylogeny ; Symbiosis/*immunology ; },
abstract = {The phylum Cnidaria is an ancient branch in the tree of metazoans. Several species exert a remarkable longevity, suggesting the existence of a developed and consistent defense mechanism of the innate immunity capable to overcome the potential repeated exposure to microbial pathogenic agents. Increasing evidence indicates that the innate immune system in Cnidarians is not only involved in the disruption of harmful microorganisms, but also is crucial in structuring tissue-associated microbial communities that are essential components of the Cnidarian holobiont and useful to the animal's health for several functions, including metabolism, immune defense, development, and behavior. Sometimes, the shifts in the normal microbiota may be used as &quot;early&quot; bio-indicators of both environmental changes and/or animal disease. Here the Cnidarians relationships with microbial communities and the potential biotechnological applications are summarized and discussed.},
}
@article {pmid30132152,
year = {2018},
author = {Hinojosa-Vidal, E and Marco, F and Martínez-Alberola, F and Escaray, FJ and García-Breijo, FJ and Reig-Armiñana, J and Carrasco, P and Barreno, E},
title = {Characterization of the responses to saline stress in the symbiotic green microalga Trebouxia sp. TR9.},
journal = {Planta},
volume = {248},
number = {6},
pages = {1473-1486},
pmid = {30132152},
issn = {1432-2048},
support = {CGL2016-391 79158-P//Ministerio de Economía y Competitividad/ ; BES-2013-065511//Ministerio de Economía y Competitividad/ ; PROMETEO/2017/039)//Generalitat Valenciana/ ; },
mesh = {Abscisic Acid/metabolism ; Ascomycota/genetics/*physiology/ultrastructure ; Chlorophyta/genetics/microbiology/*physiology/ultrastructure ; Lichens/genetics/microbiology/*physiology/ultrastructure ; Microalgae/genetics/microbiology/*physiology/ultrastructure ; Photosynthesis/drug effects ; Plant Growth Regulators/metabolism ; Salinity ; Sodium Chloride/pharmacology ; Stress, Physiological ; *Symbiosis ; },
abstract = {MAIN CONCLUSION: For the first time we provide a study on the physiological, ultrastructural and molecular effects of salt stress on a terrestrial symbiotic green microalga, Trebouxia sp. TR9. Although tolerance to saline conditions has been thoroughly studied in plants and, to an extent, free-living microalgae, scientific data regarding salt stress on symbiotic lichen microalgae is scarce to non-existent. Since lichen phycobionts are capable of enduring harsh, restrictive and rapidly changing environments, it is interesting to study the metabolic machinery operating under these extreme conditions. We aim to determine the effects of prolonged exposure to high salt concentrations on the symbiotic phycobiont Trebouxia sp. TR9, isolated from the lichen Ramalina farinacea. Our results suggest that, when this alga is confronted with extreme saline conditions, the cellular structures are affected to an extent, with limited chlorophyll content loss and photosynthetic activity remaining after 72 h of exposure to 5 M NaCl. Furthermore, this organism displays a rather different molecular response compared to land plants and free-living halophile microalgae, with no noticeable increase in ABA levels and ABA-related gene expression until the external NaCl concentration is raised to 3 M NaCl. Despite this, the ABA transduction pathway seems functional, since the ABA-related genes tested are responsive to exogenous ABA. These observations could suggest that this symbiotic green alga may have developed alternative molecular pathways to cope with highly saline environments.},
}
@article {pmid30059700,
year = {2018},
author = {Kraberger, S and Hofstetter, RW and Potter, KA and Farkas, K and Varsani, A},
title = {Genomoviruses associated with mountain and western pine beetles.},
journal = {Virus research},
volume = {256},
number = {},
pages = {17-20},
doi = {10.1016/j.virusres.2018.07.019},
pmid = {30059700},
issn = {1872-7492},
mesh = {Animals ; Arizona ; Ascomycota/growth &amp; development/virology ; Cluster Analysis ; DNA Viruses/classification/*genetics/*isolation &amp; purification ; *Genome, Viral ; Nematocera/microbiology/*virology ; Phylogeny ; Recombination, Genetic ; Sequence Homology ; Symbiosis ; },
abstract = {Genomoviruses are circular single-stranded DNA viruses (∼2 kb in size) classified into nine genera, they are highly diverse and have been identified in a variety of samples ranging from fungi to animal sera. Here we identify five genomoviruses belonging to the Gemycircularvirus genus and one to the Gemykibivirus genus from mountain pine beetle and western pine beetle sampled in Arizona. Collectively these six viral genomes share <77% genome-wide pairwise identity and hence represent six new species of genomoviruses. Four of the gemycircularviruses from the mountain pine beetles are recombinant, with one having a recombinant region that spans the entire capsid protein. Pine beetles have a symbiotic relationship with certain tree pathogenic fungi. Therefore given that Sclerotinia sclerotiorum hypovirulence-associated DNA virus 1, a gemycircularvirus, induces hypovirulence in the plant pathogenic fungus Sclerotinia sclerotiorum and infects the mycophagous insect Lycoriella ingenua, it is possible that the six genomoviruses identified here may be directly associated with the pine beetle fungal symbionts and/or with the insects themselves.},
}
@article {pmid30028247,
year = {2018},
author = {Kurečič, M and Rijavec, T and Hribernik, S and Lapanje, A and Kleinschek, KS and Maver, U},
title = {Novel electrospun fibers with incorporated commensal bacteria for potential preventive treatment of the diabetic foot.},
journal = {Nanomedicine (London, England)},
volume = {13},
number = {13},
pages = {1583-1594},
doi = {10.2217/nnm-2018-0014},
pmid = {30028247},
issn = {1748-6963},
mesh = {Biocompatible Materials/administration &amp; dosage/chemistry ; Carboxymethylcellulose Sodium/administration &amp; dosage/chemistry ; Diabetic Foot/*drug therapy/microbiology/pathology ; Humans ; Microbiota/drug effects ; Microscopy, Electron, Scanning ; Nanofibers/*administration &amp; dosage/chemistry/microbiology ; Polyethylene Glycols/chemistry/pharmacology ; Spectrometry, Mass, Matrix-Assisted Laser Desorption-Ionization ; Staphylococcus epidermidis/chemistry/*growth &amp; development/ultrastructure ; *Symbiosis ; },
abstract = {AIM: A novel electrospun biocompatible nanofibrous material loaded with commensal bacteria for potential preventive treatment of the diabetic foot was developed.<br><br>MATERIALS &amp; METHODS: Two biocompatible polymers (carboxymethylcellulose and polyethylene oxide) were combined with a bacterium isolate from the skin located between the toes of a healthy adult (identified using a matrix-assisted laser desorption/ionization mass spectrometry-based method as a strain of Staphylococcus epidermidis). Higher bacteria loads in the material were assured through their encapsulation in polyethylenimine. The nanofibrous material was characterized using scanning electron microscopy, zeta-potential measurements and through evaluation of cell growth and viability.<br><br>RESULTS &amp; DISCUSSION: nanometer formation was confirmed using scanning electron microscopy, while the zeta-potential measurements revealed successful bacteria encapsulation. Viable and sufficiently growing cells were confirmed prior and after their incorporation.<br><br>CONCLUSION: The prepared materials were proven suitable to deliver viable commensal bacteria in a comparable share to the Staphylococcaceae in the foot microbiome making this approach promising for preventive diabetic foot treatment.},
}
@article {pmid30017857,
year = {2018},
author = {Xu, L and Zhang, Y and Zhang, S and Deng, J and Lu, M and Zhang, L and Zhang, J},
title = {Comparative analysis of the immune system of an invasive bark beetle, Dendroctonus valens, infected by an entomopathogenic fungus.},
journal = {Developmental and comparative immunology},
volume = {88},
number = {},
pages = {65-69},
doi = {10.1016/j.dci.2018.07.002},
pmid = {30017857},
issn = {1879-0089},
mesh = {Animals ; Beauveria/*immunology/pathogenicity ; China ; Coleoptera/*immunology/microbiology ; Forests ; Gene Expression Profiling ; Host-Pathogen Interactions/*immunology ; Introduced Species ; Larva/immunology/microbiology ; Ophiostomatales/*immunology/pathogenicity ; Pest Control, Biological/*methods ; Phylogeny ; Pinus ; Symbiosis/immunology ; Transcriptome/immunology ; },
abstract = {Dendroctonus valens LeConte is one of the most economically important forest pest in China. Leptographium procerum, a mutualistic fungus can assist the host beetle in overcoming the pine's chemical defenses, and Beauveria bassiana, an entomopathogenic fungus has shown high beetle killing efficiency. Considering that the D. valens immune system remains unknown at the genomic level, a mutualistic and antagonistic fungus associated with the beetle provides an ideal model for studying immune interactions between the insect and associated fungi. Here, B. bassiana killed most tested larvae more effectively than L. procerum and Tween. The entomopathogenic fungus provoked stronger responses than the symbiotic fungus at the transcriptome level. We identified 185 immunity-related genes, including pattern recognition receptors, signal modulators, members of immune pathways (Toll, IMD, and JAK/STAT), and immune effectors. Quantitative real-time PCR analysis confirmed that several recognition receptors and effector genes were activated at 1 or 2 days post infection, while the effector genes were suppressed at 4 days post infection by B. bassiana, respectively. In contrast, effector genes were upregulated in response to L. procerum. Together, this study provides a comprehensive sequence resource and insight into the D. valens immune system and lays a basis for understanding the molecular aspects of the interaction between the host and associated fungi.},
}
@article {pmid29874266,
year = {2018},
author = {Vet, S and de Buyl, S and Faust, K and Danckaert, J and Gonze, D and Gelens, L},
title = {Bistability in a system of two species interacting through mutualism as well as competition: Chemostat vs. Lotka-Volterra equations.},
journal = {PloS one},
volume = {13},
number = {6},
pages = {e0197462},
pmid = {29874266},
issn = {1932-6203},
mesh = {Computer Simulation ; *Microbial Interactions ; *Models, Biological ; Netherlands ; Population Dynamics ; Symbiosis/*physiology ; },
abstract = {We theoretically study the dynamics of two interacting microbial species in the chemostat. These species are competitors for a common resource, as well as mutualists due to cross-feeding. In line with previous studies (Assaneo, et al., 2013; Holland, et al., 2010; Iwata, et al., 2011), we demonstrate that this system has a rich repertoire of dynamical behavior, including bistability. Standard Lotka-Volterra equations are not capable to describe this particular system, as these account for only one type of interaction (mutualistic or competitive). We show here that the different steady state solutions can be well captured by an extended Lotka-Volterra model, which better describe the density-dependent interaction (mutualism at low density and competition at high density). This two-variable model provides a more intuitive description of the dynamical behavior than the chemostat equations.},
}
@article {pmid29717331,
year = {2018},
author = {Houles, A and Vincent, B and David, M and Ducousso, M and Galiana, A and Juillot, F and Hannibal, L and Carriconde, F and Fritsch, E and Jourand, P},
title = {Ectomycorrhizal Communities Associated with the Legume Acacia spirorbis Growing on Contrasted Edaphic Constraints in New Caledonia.},
journal = {Microbial ecology},
volume = {76},
number = {4},
pages = {964-975},
pmid = {29717331},
issn = {1432-184X},
support = {N° 2013/1434//CIFRE/ ; ANR-12-ADAP-0017 ADASPIR//Agence Nationale pour la Recherche (FR)/ ; },
mesh = {Acacia/growth &amp; development/*microbiology ; Basidiomycota/classification/*physiology ; Mycorrhizae/classification/*physiology ; New Caledonia ; Soil/*chemistry ; *Soil Microbiology ; Symbiosis ; },
abstract = {This study aims to characterize the ectomycorrhizal (ECM) communities associated with Acacia spirorbis, a legume tree widely spread in New Caledonia that spontaneously grows on contrasted edaphic constraints, i.e. calcareous, ferralitic and volcano-sedimentary soils. Soil geochemical parameters and diversity of ECM communities were assessed in 12 sites representative of the three mains categories of soils. The ectomycorrhizal status of Acacia spirorbis was confirmed in all studied soils, with a fungal community dominated at 92% by Basidiomycota, mostly represented by/tomentella-thelephora (27.6%), /boletus (15.8%), /sebacina (10.5%), /russula-lactarius (10.5%) and /pisolithus-scleroderma (7.9%) lineages. The diversity and the proportion of the ECM lineages were similar for the ferralitic and volcano-sedimentary soils but significantly different for the calcareous soils. These differences in the distribution of the ECM communities were statistically correlated with pH, Ca, P and Al in the calcareous soils and with Co in the ferralitic soils. Altogether, these data suggest a high capacity of A. spirorbis to form ECM symbioses with a large spectrum of fungi regardless the soil categories with contrasted edaphic parameters.},
}
@article {pmid29675704,
year = {2018},
author = {Saucedo-Carabez, JR and Ploetz, RC and Konkol, JL and Carrillo, D and Gazis, R},
title = {Partnerships Between Ambrosia Beetles and Fungi: Lineage-Specific Promiscuity Among Vectors of the Laurel Wilt Pathogen, Raffaelea lauricola.},
journal = {Microbial ecology},
volume = {76},
number = {4},
pages = {925-940},
pmid = {29675704},
issn = {1432-184X},
mesh = {Animals ; Female ; Florida ; Ophiostomatales/*physiology ; Persea/*microbiology ; Plant Diseases/*microbiology ; *Symbiosis ; Weevils/classification/*microbiology ; },
abstract = {Nutritional mutualisms that ambrosia beetles have with fungi are poorly understood. Although these interactions were initially thought to be specific associations with a primary symbiont, there is increasing evidence that some of these fungi are associated with, and move among, multiple beetle partners. We examined culturable fungi recovered from mycangia of ambrosia beetles associated with trees of Persea humilis (silk bay, one site) and P. americana (avocado, six commercial orchards) that were affected by laurel wilt, an invasive disease caused by a symbiont, Raffaelea lauricola, of an Asian ambrosia beetle, Xyleborus glabratus. Fungi were isolated from 20 adult females of X. glabratus from silk bay and 70 each of Xyleborus affinis, Xyleborus bispinatus, Xyleborus volvulus, Xyleborinus saxesenii, and Xylosandrus crassiusculus from avocado. With partial sequences of ribosomal (LSU and SSU) and nuclear (β-tubulin) genes, one to several operational taxonomic units (OTUs) of fungi were identified in assayed individuals. Distinct populations of fungi were recovered from each of the examined beetle species. Raffaelea lauricola was present in all beetles except X. saxesenii and X. crassiusculus, and Raffaelea spp. predominated in Xyleborus spp. Raffaelea arxii, R. subalba, and R. subfusca were present in more than a single species of Xyleborus, and R. arxii was the most abundant symbiont in both X. affinis and X. volvulus. Raffaelea aguacate was detected for the first time in an ambrosia beetle (X. bispinatus). Yeasts (Ascomycota, Saccharomycotina) were found consistently in the mycangia of the examined beetles, and distinct, putatively co-adapted populations of these fungi were associated with each beetle species. Greater understandings are needed for how mycangia in ambrosia beetles interact with fungi, including yeasts which play currently underresearched roles in these insects.},
}
@article {pmid29663039,
year = {2018},
author = {Birnbaum, C and Bissett, A and Teste, FP and Laliberté, E},
title = {Symbiotic N2-Fixer Community Composition, but Not Diversity, Shifts in Nodules of a Single Host Legume Across a 2-Million-Year Dune Chronosequence.},
journal = {Microbial ecology},
volume = {76},
number = {4},
pages = {1009-1020},
pmid = {29663039},
issn = {1432-184X},
support = {DE120100352//Australian Research Council/ ; DP130100016//Australian Research Council/ ; },
mesh = {Acacia/metabolism/*microbiology ; Environment ; Microbiota ; *Nitrogen Fixation ; Oxidoreductases/analysis ; Plant Proteins/analysis ; Root Nodules, Plant/metabolism/*microbiology ; Soil/*chemistry ; *Soil Microbiology ; Symbiosis ; Western Australia ; },
abstract = {Long-term soil age gradients are useful model systems to study how changes in nutrient limitation shape communities of plant root mutualists because they represent strong natural gradients of nutrient availability, particularly of nitrogen (N) and phosphorus (P). Here, we investigated changes in the dinitrogen (N2)-fixing bacterial community composition and diversity in nodules of a single host legume (Acacia rostellifera) across the Jurien Bay chronosequence, a retrogressive 2 million-year-old sequence of coastal dunes representing an exceptionally strong natural soil fertility gradient. We collected nodules from plants grown in soils from five chronosequence stages ranging from very young (10s of years; associated with strong N limitation for plant growth) to very old (> 2,000,000 years; associated with strong P limitation), and sequenced the nifH gene in root nodules to determine the composition and diversity of N2-fixing bacterial symbionts. A total of 335 unique nifH gene operational taxonomic units (OTUs) were identified. Community composition of N2-fixing bacteria within nodules, but not diversity, changed with increasing soil age. These changes were attributed to pedogenesis-driven shifts in edaphic conditions, specifically pH, exchangeable manganese, resin-extractable phosphate, nitrate and nitrification rate. A large number of common N2-fixing bacteria genera (e.g. Bradyrhizobium, Ensifer, Mesorhizobium and Rhizobium) belonging to the Rhizobiaceae family (α-proteobacteria) comprised 70% of all raw sequences and were present in all nodules. However, the oldest soils, which show some of the lowest soil P availability ever recorded, harboured the largest proportion of unclassified OTUs, suggesting a unique set of N2-fixing bacteria adapted to extreme P limitation. Our results show that N2-fixing bacterial composition varies strongly during long-term ecosystem development, even within the same host, and therefore rhizobia show strong edaphic preferences.},
}
@article {pmid29516314,
year = {2018},
author = {Li, L and Mohamad, OAA and Ma, J and Friel, AD and Su, Y and Wang, Y and Musa, Z and Liu, Y and Hedlund, BP and Li, W},
title = {Synergistic plant-microbe interactions between endophytic bacterial communities and the medicinal plant Glycyrrhiza uralensis F.},
journal = {Antonie van Leeuwenhoek},
volume = {111},
number = {10},
pages = {1735-1748},
doi = {10.1007/s10482-018-1062-4},
pmid = {29516314},
issn = {1572-9699},
support = {31200008//National Natural Science Foundation of China/ ; 31670009//National Natural Science Foundation of China/ ; 201509655013//China Scholarship Council/ ; },
mesh = {Bacteria/*classification/isolation &amp; purification/metabolism ; *Bacterial Physiological Phenomena ; *Endophytes ; Glycyrrhiza uralensis/*microbiology/*physiology ; Lipolysis ; Microbiota ; Molecular Typing ; Nitrogen Fixation ; Phosphates/metabolism ; Plants, Medicinal/microbiology ; Proteolysis ; Quantitative Trait, Heritable ; *Symbiosis ; },
abstract = {Little is known about the composition, diversity, and geographical distribution of bacterial communities associated with medicinal plants in arid lands. To address this, a collection of 116 endophytic bacteria were isolated from wild populations of the herb Glycyrrhiza uralensis Fisch (licorice) in Xinyuan, Gongliu, and Tekesi of Xinjiang Province, China, and identified based on their 16S rRNA gene sequences. The endophytes were highly diverse, including 20 genera and 35 species. The number of distinct bacterial genera obtained from root tissues was higher (n = 14) compared to stem (n = 9) and leaf (n = 6) tissue. Geographically, the diversity of culturable endophytic genera was higher at the Tekesi (n = 14) and Xinyuan (n = 12) sites than the Gongliu site (n = 4), reflecting the extremely low organic carbon content, high salinity, and low nutrient status of Gongliu soils. The endophytic bacteria exhibited a number of plant growth-promoting activities ex situ, including diazotrophy, phosphate and potassium solubilization, siderophore production, auxin synthesis, and production of hydrolytic enzymes. Twelve endophytes were selected based on their ex situ plant growth-promoting activities for growth chamber assays to test for their ability to promote growth of G. uralensis F. and Triticum aestivum (wheat) plants. Several strains belonging to the genera Bacillus (n = 6) and Achromobacter (n = 1) stimulated total biomass production in both G. uralensis and T. aestivum under low-nutrient conditions. This work is the first report on the isolation and characterization of endophytes associated with G. uralensis F. in arid lands. The results demonstrate the broad diversity of endophytes associated with wild licorice and suggest that some Bacillus strains may be promising candidates for biofertilizers to promote enhanced survival and growth of licorice and other valuable crops in arid environments.},
}
@article {pmid29501373,
year = {2018},
author = {Horká, I and De Grave, S and Fransen, CHJM and Petrusek, A and Ďuriš, Z},
title = {Multiple origins and strong phenotypic convergence in fish-cleaning palaemonid shrimp lineages.},
journal = {Molecular phylogenetics and evolution},
volume = {124},
number = {},
pages = {71-81},
doi = {10.1016/j.ympev.2018.02.006},
pmid = {29501373},
issn = {1095-9513},
mesh = {Acclimatization ; Animals ; Bayes Theorem ; Behavior, Animal ; Likelihood Functions ; Palaemonidae/*physiology ; Perciformes/*physiology ; Phenotype ; *Phylogeny ; Pigmentation ; *Symbiosis ; },
abstract = {Several species of palaemonid shrimps are known to act as fish-cleaning symbionts, with cleaning interactions ranging from dedicated (obligate) to facultative. We confirmed five evolutionarily independent origins of fish cleaning symbioses within the family Palaemonidae based on a phylogenetic analysis and the ancestral state reconstruction of 68 species, including 13 fish-cleaners from the genera Ancylomenes, Brachycarpus, Palaemon, Periclimenes, and Urocaridella. We focus in particular on two distantly related lineages of fish cleaning shrimps with allopatric distributions, the Indo-West Pacific Ancylomenes and the western Atlantic monophyletic Ancylomenes/Periclimenes group, which exhibit striking similarities in morphology, colouration and complex behaviour. Specifically, representatives of both lineages are similar in: (1) the general body shape and colour pattern; (2) the utilization of sea anemones as conspicuous cleaning stations; and (3) the use of sideways body swaying to visually promote their bright colour spots in order to attract fish clients. Such morphological, ecological and ethological convergences are apparently due to adaptations to fish cleaning linked to the establishment of similar modes of communication with fish clients in these species.},
}
@article {pmid29426952,
year = {2018},
author = {Volland, JM and Schintlmeister, A and Zambalos, H and Reipert, S and Mozetič, P and Espada-Hinojosa, S and Turk, V and Wagner, M and Bright, M},
title = {NanoSIMS and tissue autoradiography reveal symbiont carbon fixation and organic carbon transfer to giant ciliate host.},
journal = {The ISME journal},
volume = {12},
number = {3},
pages = {714-727},
pmid = {29426952},
issn = {1751-7370},
support = {294343//European Research Council/International ; P 24565//Austrian Science Fund FWF/Austria ; },
mesh = {Autoradiography ; Carbon/metabolism ; Carbon Cycle ; Chemoautotrophic Growth ; Gammaproteobacteria/genetics/*physiology ; In Situ Hybridization, Fluorescence ; Mass Spectrometry ; Oligohymenophorea/*microbiology/*physiology ; Oxidation-Reduction ; Sulfides/metabolism ; *Symbiosis ; },
abstract = {The giant colonial ciliate Zoothamnium niveum harbors a monolayer of the gammaproteobacteria Cand. Thiobios zoothamnicoli on its outer surface. Cultivation experiments revealed maximal growth and survival under steady flow of high oxygen and low sulfide concentrations. We aimed at directly demonstrating the sulfur-oxidizing, chemoautotrophic nature of the symbionts and at investigating putative carbon transfer from the symbiont to the ciliate host. We performed pulse-chase incubations with 14C- and 13C-labeled bicarbonate under varying environmental conditions. A combination of tissue autoradiography and nanoscale secondary ion mass spectrometry coupled with transmission electron microscopy was used to follow the fate of the radioactive and stable isotopes of carbon, respectively. We show that symbiont cells fix substantial amounts of inorganic carbon in the presence of sulfide, but also (to a lesser degree) in the absence of sulfide by utilizing internally stored sulfur. Isotope labeling patterns point to translocation of organic carbon to the host through both release of these compounds and digestion of symbiont cells. The latter mechanism is also supported by ultracytochemical detection of acid phosphatase in lysosomes and in food vacuoles of ciliate cells. Fluorescence in situ hybridization of freshly collected ciliates revealed that the vast majority of ingested microbial cells were ectosymbionts.},
}
@article {pmid29410456,
year = {2018},
author = {Guidolin, AS and Cataldi, TR and Labate, CA and Francis, F and Cônsoli, FL},
title = {Spiroplasma affects host aphid proteomics feeding on two nutritional resources.},
journal = {Scientific reports},
volume = {8},
number = {1},
pages = {2466},
pmid = {29410456},
issn = {2045-2322},
mesh = {Amino Acids/biosynthesis ; Animals ; Aphids/*genetics/metabolism/microbiology ; Carbohydrate Metabolism/genetics ; Citrus sinensis/*chemistry/parasitology ; Energy Metabolism/genetics ; Gene Expression ; Gene Expression Profiling ; Gene Ontology ; Heat-Shock Proteins/genetics/metabolism ; Insect Proteins/*genetics/metabolism ; Molecular Sequence Annotation ; Proteome/*genetics/metabolism ; Proteomics/methods ; Spiroplasma/*physiology ; Symbiosis/*physiology ; },
abstract = {Bacterial symbionts are broadly distributed among insects, influencing their bioecology to different degrees. Aphids carry a number of secondary symbionts that can influence aphid physiology and fitness attributes. Spiroplasma is seldom reported as an aphid symbiont, but a high level of infection has been observed in one population of the tropical aphid Aphis citricidus. We used sister isolines of Spiroplasma-infected (Ac-BS) and Spiroplasma-free (Ac-B) aphids reared on sweet orange (optimum host) and orange jasmine (suboptimum host) to demonstrate the effects of Spiroplasma infection in the aphid proteome profile. A higher number of proteins were differently abundant in aphids feeding on orange jasmine, indicating an impact of host plant quality. In both host plants, the majority of proteins affected by Spiroplasma infection were heat shock proteins, proteins linked to cell function and structure, and energy metabolism. Spiroplasma also induced changes in proteins involved in antimicrobial activity, carbohydrate processing and metabolism, amino acid synthesis and metabolism in aphids feeding on orange jasmine. We discuss on how the aphid host proteome is differentially affected by Spiroplasma infection when the host is exploiting host plants with different nutritional values.},
}
@article {pmid29396559,
year = {2018},
author = {Massé, A and Domart-Coulon, I and Golubic, S and Duché, D and Tribollet, A},
title = {Early skeletal colonization of the coral holobiont by the microboring Ulvophyceae Ostreobium sp.},
journal = {Scientific reports},
volume = {8},
number = {1},
pages = {2293},
pmid = {29396559},
issn = {2045-2322},
mesh = {Animal Shells/*microbiology ; Animals ; Anthozoa/*microbiology ; Chlorophyta/classification/genetics/*growth &amp; development ; Genetic Variation ; Metagenome ; Ribulose-Bisphosphate Carboxylase/genetics ; *Symbiosis ; },
abstract = {Ostreobium sp. (Bryopsidales, Ulvophyceae) is a major microboring alga involved in tropical reef dissolution, with a proposed symbiotic lifestyle in living corals. However, its diversity and colonization dynamics in host's early life stages remained unknown. Here, we mapped microborer distribution and abundance in skeletons of the branching coral Pocillopora damicornis from the onset of calcification in primary polyps (7 days) to budding juvenile colonies (1 and 3 months) growing on carbonate and non-carbonate substrates pre-colonized by natural biofilms, and compared them to adult colonies (in aquarium settings). Primary polyps were surprisingly already colonized by microboring filaments and their level of invasion depended on the nature of settlement substrate and the extent of its pre-colonization by microborers. Growth of early coral recruits was unaffected even when microborers were in close vicinity to the polyp tissue. In addition to morphotype observations, chloroplast-encoded rbcL gene sequence analyses revealed nine new Ostreobium clades (OTU99%) in Pocillopora coral. Recruits and adults shared one dominant rbcL clade, undetected in larvae, but also present in aquarium seawater, carbonate and non-carbonate settlement substrates, and in corals from reef settings. Our results show a substratum-dependent colonization by Ostreobium clades, and indicate horizontal transmission of Ostreobium-coral associations.},
}
@article {pmid29396397,
year = {2018},
author = {Watanabe, S and Yoshimura, J and Hasegawa, E},
title = {Ants improve the reproduction of inferior morphs to maintain a polymorphism in symbiont aphids.},
journal = {Scientific reports},
volume = {8},
number = {1},
pages = {2313},
pmid = {29396397},
issn = {2045-2322},
mesh = {Animals ; Ants/*physiology ; Aphids/*growth &amp; development ; Biodiversity ; Biological Variation, Population ; *Polymorphism, Genetic ; *Sexual Behavior, Animal ; *Symbiosis ; },
abstract = {Identifying stable polymorphisms is essential for understanding biodiversity. Distinctive polymorphisms are rare in nature because a superior morph should dominate a population. In addition to the three known mechanisms for polymorphism persistence, we recently reported a fourth mechanism: protection of the polymorphism by symbionts. Attending ants preferentially protect polymorphic aphid colonies consisting of green and red morphs. Here, we show that attending ants manipulate the reproductive rate of their preferred green morphs to equal that of the red morphs, leading to the persistence of the polymorphism within the colonies. We could not, however, explain how the ants maintained the polymorphism in aphid colonies regardless of inter-morph competition. Manipulation by symbionts may be important for the maintenance of polymorphisms and the resulting biodiversity in certain symbiotic systems.},
}
@article {pmid29382931,
year = {2018},
author = {Wang, B and Lu, M and Cook, JM and Yang, DR and Dunn, DW and Wang, RW},
title = {Chemical camouflage: a key process in shaping an ant-treehopper and fig-fig wasp mutualistic network.},
journal = {Scientific reports},
volume = {8},
number = {1},
pages = {1833},
pmid = {29382931},
issn = {2045-2322},
mesh = {Animals ; Ants/*physiology ; Biological Evolution ; Biological Mimicry/*physiology ; Ficus/parasitology ; Hemiptera/*physiology ; Host-Parasite Interactions/physiology ; Hydrocarbons/metabolism ; Inflorescence/physiology ; Pollination/physiology ; Predatory Behavior/physiology ; Seeds/parasitology ; Symbiosis/*physiology ; Wasps/*physiology ; },
abstract = {Different types of mutualisms may interact, co-evolve and form complex networks of interdependences, but how species interact in networks of a mutualistic community and maintain its stability remains unclear. In a mutualistic network between treehoppers-weaver ants and fig-pollinating wasps, we found that the cuticular hydrocarbons of the treehoppers are more similar to the surface chemical profiles of fig inflorescence branches (FIB) than the cuticular hydrocarbons of the fig wasps. Behavioral assays showed that the cuticular hydrocarbons from both treehoppers and FIBs reduce the propensity of weaver ants to attack treehoppers even in the absence of honeydew rewards, suggesting that chemical camouflage helps enforce the mutualism between weaver ants and treehoppers. High levels of weaver ant and treehopper abundances help maintain the dominance of pollinating fig wasps in the fig wasp community and also increase fig seed production, as a result of discriminative predation and disturbance by weaver ants of ovipositing non-pollinating fig wasps (NPFWs). Ants therefore help preserve this fig-pollinating wasp mutualism from over exploitation by NPFWs. Our results imply that in this mutualistic network chemical camouflage plays a decisive role in regulating the behavior of a key species and indirectly shaping the architecture of complex arthropod-plant interactions.},
}
@article {pmid29321691,
year = {2018},
author = {Mohamed, AR and Cumbo, VR and Harii, S and Shinzato, C and Chan, CX and Ragan, MA and Satoh, N and Ball, EE and Miller, DJ},
title = {Deciphering the nature of the coral-Chromera association.},
journal = {The ISME journal},
volume = {12},
number = {3},
pages = {776-790},
pmid = {29321691},
issn = {1751-7370},
mesh = {Alveolata/genetics/*physiology ; Animals ; Anthozoa/genetics/growth &amp; development/*parasitology/physiology ; Biological Evolution ; Coral Reefs ; Larva/genetics/growth &amp; development/metabolism/parasitology ; Photosynthesis ; *Symbiosis ; Transcriptome ; },
abstract = {Since the discovery of Chromera velia as a novel coral-associated microalga, this organism has attracted interest because of its unique evolutionary position between the photosynthetic dinoflagellates and the parasitic apicomplexans. The nature of the relationship between Chromera and its coral host is controversial. Is it a mutualism, from which both participants benefit, a parasitic relationship, or a chance association? To better understand the interaction, larvae of the common Indo-Pacific reef-building coral Acropora digitifera were experimentally infected with Chromera, and the impact on the host transcriptome was assessed at 4, 12, and 48 h post-infection using Illumina RNA-Seq technology. The transcriptomic response of the coral to Chromera was complex and implies that host immunity is strongly suppressed, and both phagosome maturation and the apoptotic machinery is modified. These responses differ markedly from those described for infection with a competent strain of the coral mutualist Symbiodinium, instead resembling those of vertebrate hosts to parasites and/or pathogens such as Mycobacterium tuberculosis. Consistent with ecological studies suggesting that the association may be accidental, the transcriptional response of A. digitifera larvae leads us to conclude that Chromera could be a coral parasite, commensal, or accidental bystander, but certainly not a beneficial mutualist.},
}
@article {pmid29026656,
year = {2017},
author = {Harris, HMB and Bourin, MJB and Claesson, MJ and O'Toole, PW},
title = {Phylogenomics and comparative genomics of Lactobacillus salivarius, a mammalian gut commensal.},
journal = {Microbial genomics},
volume = {3},
number = {8},
pages = {e000115},
pmid = {29026656},
issn = {2057-5858},
mesh = {Animals ; Gastrointestinal Microbiome/*genetics ; *Genome, Bacterial ; Genomics ; Lactobacillus salivarius/*genetics ; Mammals ; Phylogeny ; Symbiosis/*genetics ; },
abstract = {The genus Lactobacillus is a diverse group with a combined species count of over 200. They are the largest group within the lactic acid bacteria and one of the most important bacterial groups involved in food microbiology and human nutrition because of their fermentative and probiotic properties. Lactobacillus salivarius, a species commonly isolated from the gastrointestinal tract of humans and animals, has been described as having potential probiotic properties and results of previous studies have revealed considerable functional diversity existing on both the chromosomes and plasmids. Our study consists of comparative genomic analyses of the functional and phylogenomic diversity of 42 genomes of strains of L. salivarius using bioinformatic techniques. The main aim of the study was to describe intra-species diversity and to determine how this diversity is spread across the replicons. We found that multiple phylogenomic and non-phylogenomic methods used for reconstructing trees all converge on similar tree topologies, showing that different metrics largely agree on the evolutionary history of the species. The greatest genomic variation lies on the small plasmids, followed by the repA-type circular megaplasmid, with the chromosome varying least of all. Additionally, the presence of extra linear and circular megaplasmids is noted in several strains, while small plasmids are not always present. Glycosyl hydrolases, bacteriocins and proteases vary considerably on all replicons while two exopolysaccharide clusters and several clustered regularly interspaced short palindromic repeats-associated systems show a lot of variation on the chromosome. Overall, despite its reputation as a mammalian gastrointestinal tract specialist, the intra-specific variation of L. salivarius reveals potential strain-dependant effects on human health.},
}
@article {pmid28812548,
year = {2018},
author = {Kuhn, KA and Schulz, HM and Regner, EH and Severs, EL and Hendrickson, JD and Mehta, G and Whitney, AK and Ir, D and Ohri, N and Robertson, CE and Frank, DN and Campbell, EL and Colgan, SP},
title = {Bacteroidales recruit IL-6-producing intraepithelial lymphocytes in the colon to promote barrier integrity.},
journal = {Mucosal immunology},
volume = {11},
number = {2},
pages = {357-368},
pmid = {28812548},
issn = {1935-3456},
support = {R37 DK050189/DK/NIDDK NIH HHS/United States ; R29 DK050189/DK/NIDDK NIH HHS/United States ; R01 DK103639/DK/NIDDK NIH HHS/United States ; K08 DK107905/DK/NIDDK NIH HHS/United States ; R01 DK050189/DK/NIDDK NIH HHS/United States ; T32 AR007534/AR/NIAMS NIH HHS/United States ; R01 DK104713/DK/NIDDK NIH HHS/United States ; },
mesh = {Animals ; Bacteroidaceae/*physiology ; Cell Membrane Permeability/genetics ; Citrobacter rodentium/*immunology ; Colon/*immunology ; Dysbiosis/*immunology ; Enterobacteriaceae Infections/*immunology ; Gastrointestinal Microbiome/*immunology ; Homeostasis ; Immunity, Innate ; Interleukin-6/genetics/*metabolism ; Intestinal Mucosa/*physiology ; Intraepithelial Lymphocytes/microbiology/*physiology ; Mice, Inbred C57BL ; Mice, Knockout ; Myeloid Differentiation Factor 88/metabolism ; RNA, Ribosomal, 16S/genetics ; Symbiosis ; },
abstract = {Interactions between the microbiota and distal gut are important for the maintenance of a healthy intestinal barrier; dysbiosis of intestinal microbial communities has emerged as a likely contributor to diseases that arise at the level of the mucosa. Intraepithelial lymphocytes (IELs) are positioned within the epithelial barrier, and in the small intestine they function to maintain epithelial homeostasis. We hypothesized that colon IELs promote epithelial barrier function through the expression of cytokines in response to interactions with commensal bacteria. Profiling of bacterial 16S ribosomal RNA revealed that candidate bacteria in the order Bacteroidales are sufficient to promote IEL presence in the colon that in turn produce interleukin-6 (IL-6) in a MyD88 (myeloid differentiation primary response 88)-dependent manner. IEL-derived IL-6 is functionally important in the maintenance of the epithelial barrier as IL-6-/- mice were noted to have increased paracellular permeability, decreased claudin-1 expression, and a thinner mucus gel layer, all of which were reversed by transfer of IL-6+/+ IELs, leading to protection of mice in response to Citrobacter rodentium infection. Therefore, we conclude that microbiota provide a homeostatic role for epithelial barrier function through regulation of IEL-derived IL-6.},
}
@article {pmid28631141,
year = {2018},
author = {Lee, KR and Wakeel, A and Chakraborty, P and Foote, CS and Kajiura, L and Barrozo, JC and Chan, AC and Bazarov, AV and Spitler, R and Kutny, PM and Denegre, JM and Taft, RA and Seemann, J and Rice, BW and Contag, CH and Rutt, BK and Bell, CB},
title = {Cell Labeling with Magneto-Endosymbionts and the Dissection of the Subcellular Location, Fate, and Host Cell Interactions.},
journal = {Molecular imaging and biology : MIB : the official publication of the Academy of Molecular Imaging},
volume = {20},
number = {1},
pages = {55-64},
pmid = {28631141},
issn = {1860-2002},
support = {T32 CA009695/CA/NCI NIH HHS/United States ; R43 EB019239/EB/NIBIB NIH HHS/United States ; T32 CA 009695/CA/NCI NIH HHS/United States ; R44 EB019239/EB/NIBIB NIH HHS/United States ; R43EB019239/EB/NIBIB NIH HHS/United States ; R43 TR001202/TR/NCATS NIH HHS/United States ; R01 EB019458/EB/NIBIB NIH HHS/United States ; S10 RR026351/RR/NCRR NIH HHS/United States ; R43TR001202/TR/NCATS NIH HHS/United States ; R01 GM096070/GM/NIGMS NIH HHS/United States ; },
mesh = {Animals ; Autophagy ; *Cell Communication ; Cell Line, Tumor ; *Cell Tracking ; Contrast Media/chemistry ; Ferrozine/metabolism ; Humans ; Iron/metabolism ; Magnetite Nanoparticles/*chemistry/ultrastructure ; Mice, Inbred BALB C ; Rats ; Reproducibility of Results ; *Staining and Labeling ; Subcellular Fractions/metabolism ; *Symbiosis ; },
abstract = {PURPOSE: The purposes of this study are to characterize magneto-endosymbiont (ME) labeling of mammalian cells and to discern the subcellular fate of these living contrast agents. MEs are novel magnetic resonance imaging (MRI) contrast agents that are being used for cell tracking studies. Understanding the fate of MEs in host cells is valuable for designing in vivo cell tracking experiments.<br><br>PROCEDURES: The ME's surface epitopes, contrast-producing paramagnetic magnetosomal iron, and genome were studied using immunocytochemistry (ICC), Fe and MRI contrast measurements, and quantitative polymerase chain reaction (qPCR), respectively. These assays, coupled with other common assays, enabled validation of ME cell labeling and dissection of ME subcellular processing.<br><br>RESULTS: The assays mentioned above provide qualitative and quantitative assessments of cell labeling, the subcellular localization and the fate of MEs. ICC results, with an ME-specific antibody, qualitatively shows homogenous labeling with MEs. The ferrozine assay shows that MEs have an average of 7 fg Fe/ME, ∼30 % of which contributes to MRI contrast and ME-labeled MDA-MB-231 (MDA-231) cells generally have 2.4 pg Fe/cell, implying ∼350 MEs/cell. Adjusting the concentration of Fe in the ME growth media reduces the concentration of non-MRI contrast-producing Fe. Results from the qPCR assay, which quantifies ME genomes in labeled cells, shows that processing of MEs begins within 24 h in MDA-231 cells. ICC results suggest this intracellular digestion of MEs occurs by the lysosomal degradation pathway. MEs coated with listeriolysin O (LLO) are able to escape the primary phagosome, but subsequently co-localize with LC3, an autophagy-associated molecule, and are processed for digestion. In embryos, where autophagy is transiently suppressed, MEs show an increased capacity for survival and even replication. Finally, transmission electron microscopy (TEM) of ME-labeled MDA-231 cells confirms that the magnetosomes (the MRI contrast-producing particles) remain intact and enable in vivo cell tracking.<br><br>CONCLUSIONS: MEs are used to label mammalian cells for the purpose of cell tracking in vivo, with MRI. Various assays described herein (ICC, ferrozine, and qPCR) allow qualitative and quantitative assessments of labeling efficiency and provide a detailed understanding of subcellular processing of MEs. In some cell types, MEs are digested, but the MRI-producing particles remain. Coating with LLO allows MEs to escape the primary phagosome, enhances retention slightly, and confirms that MEs are ultimately processed by autophagy. Numerous intracellular bacteria and all endosymbiotically derived organelles have evolved molecular mechanisms to avoid intracellular clearance, and identification of the specific processes involved in ME clearance provides a framework on which to develop MEs with enhanced retention in mammalian cells.},
}
@article {pmid28616842,
year = {2018},
author = {Brewer, KD and Spitler, R and Lee, KR and Chan, AC and Barrozo, JC and Wakeel, A and Foote, CS and Machtaler, S and Rioux, J and Willmann, JK and Chakraborty, P and Rice, BW and Contag, CH and Bell, CB and Rutt, BK},
title = {Characterization of Magneto-Endosymbionts as MRI Cell Labeling and Tracking Agents.},
journal = {Molecular imaging and biology : MIB : the official publication of the Academy of Molecular Imaging},
volume = {20},
number = {1},
pages = {65-73},
pmid = {28616842},
issn = {1860-2002},
support = {T32 CA009695/CA/NCI NIH HHS/United States ; T32 CA 009695/CA/NCI NIH HHS/United States ; R43 TR001202/TR/NCATS NIH HHS/United States ; S10 RR026351/RR/NCRR NIH HHS/United States ; RT2-02018//California Institute for Regenerative Medicine/International ; 1R43TR001202-01/NH/NIH HHS/United States ; },
mesh = {Animals ; Cell Line, Tumor ; Cell Survival ; *Cell Tracking ; Female ; Humans ; *Magnetic Resonance Imaging ; Magnetite Nanoparticles/*chemistry ; Mice, Nude ; *Symbiosis ; },
abstract = {PURPOSE: Magneto-endosymbionts (MEs) show promise as living magnetic resonance imaging (MRI) contrast agents for in vivo cell tracking. Here we characterize the biomedical imaging properties of ME contrast agents, in vitro and in vivo.<br><br>PROCEDURES: By adapting and engineering magnetotactic bacteria to the intracellular niche, we are creating magneto-endosymbionts (MEs) that offer advantages relative to passive iron-based contrast agents (superparamagnetic iron oxides, SPIOs) for cell tracking. This work presents a biomedical imaging characterization of MEs including: MRI transverse relaxivity (r 2) for MEs and ME-labeled cells (compared to a commercially available iron oxide nanoparticle); microscopic validation of labeling efficiency and subcellular locations; and in vivo imaging of a MDA-MB-231BR (231BR) human breast cancer cells in a mouse brain.<br><br>RESULTS: At 7T, r 2 relaxivity of bare MEs was higher (250 s-1 mM-1) than that of conventional SPIO (178 s-1 mM-1). Optimized in vitro loading of MEs into 231BR cells yielded 1-4 pg iron/cell (compared to 5-10 pg iron/cell for conventional SPIO). r 2 relaxivity dropped by a factor of ~3 upon loading into cells, and was on the same order of magnitude for ME-loaded cells compared to SPIO-loaded cells. In vivo, ME-labeled cells exhibited strong MR contrast, allowing as few as 100 cells to be detected in mice using an optimized 3D SPGR gradient-echo sequence.<br><br>CONCLUSIONS: Our results demonstrate the potential of magneto-endosymbionts as living MR contrast agents. They have r 2 relaxivity values comparable to traditional iron oxide nanoparticle contrast agents, and provide strong MR contrast when loaded into cells and implanted in tissue.},
}
@article {pmid30521551,
year = {2018},
author = {Vernocchi, P and Del Chierico, F and Russo, A and Majo, F and Rossitto, M and Valerio, M and Casadei, L and La Storia, A and De Filippis, F and Rizzo, C and Manetti, C and Paci, P and Ercolini, D and Marini, F and Fiscarelli, EV and Dallapiccola, B and Lucidi, V and Miccheli, A and Putignani, L},
title = {Gut microbiota signatures in cystic fibrosis: Loss of host CFTR function drives the microbiota enterophenotype.},
journal = {PloS one},
volume = {13},
number = {12},
pages = {e0208171},
doi = {10.1371/journal.pone.0208171},
pmid = {30521551},
issn = {1932-6203},
abstract = {BACKGROUND: Cystic fibrosis (CF) is a disorder affecting the respiratory, digestive, reproductive systems and sweat glands. This lethal hereditary disease has known or suspected links to the dysbiosis gut microbiota. High-throughput meta-omics-based approaches may assist in unveiling this complex network of symbiosis modifications.<br><br>OBJECTIVES: The aim of this study was to provide a predictive and functional model of the gut microbiota enterophenotype of pediatric patients affected by CF under clinical stability.<br><br>METHODS: Thirty-one fecal samples were collected from CF patients and healthy children (HC) (age range, 1-6 years) and analysed using targeted-metagenomics and metabolomics to characterize the ecology and metabolism of CF-linked gut microbiota. The multidimensional data were low fused and processed by chemometric classification analysis.<br><br>RESULTS: The fused metagenomics and metabolomics based gut microbiota profile was characterized by a high abundance of Propionibacterium, Staphylococcus and Clostridiaceae, including Clostridium difficile, and a low abundance of Eggerthella, Eubacterium, Ruminococcus, Dorea, Faecalibacterium prausnitzii, and Lachnospiraceae, associated with overexpression of 4-aminobutyrate (GABA), choline, ethanol, propylbutyrate, and pyridine and low levels of sarcosine, 4-methylphenol, uracil, glucose, acetate, phenol, benzaldehyde, and methylacetate. The CF gut microbiota pattern revealed an enterophenotype intrinsically linked to disease, regardless of age, and with dysbiosis uninduced by reduced pancreatic function and only partially related to oral antibiotic administration or lung colonization/infection.<br><br>CONCLUSIONS: All together, the results obtained suggest that the gut microbiota enterophenotypes of CF, together with endogenous and bacterial CF biomarkers, are direct expression of functional alterations at the intestinal level. Hence, it's possible to infer that CFTR impairment causes the gut ecosystem imbalance.This new understanding of CF host-gut microbiota interactions may be helpful to rationalize novel clinical interventions to improve the affected children's nutritional status and intestinal function.},
}
@article {pmid30520354,
year = {2018},
author = {Yoshikawa, A and Goto, R and Asakura, A},
title = {Morphology and Habitats of the Hermit-Crab-Associated Calyptraeid Gastropod Ergaea walshi.},
journal = {Zoological science},
volume = {35},
number = {6},
pages = {494-504},
doi = {10.2108/zs180046},
pmid = {30520354},
issn = {0289-0003},
abstract = {Ergaea walshi, a gastropod with a markedly flat shell, often lives inside empty snail shells occupied by hermit crabs. We investigated its lifestyle, shell growth pattern, and habitat preference for host hermit crabs and host snail shells. Four hundred sixteen snail shells, including 363 shells with hermit crabs and 53 empty shells, were collected from intertidal zones of sandy and muddy flats around Kii Peninsula, Japan. The specimens comprised seven hermit crab species occupying 24 shell species; E. walshi was harbored in 13.2% of snail shells with hermit crabs and 17.0% of those without hermit crabs. Although no preference was detected for particular species of hermit crab or snail shell, E. walshi preferred to live inside of snail shells with wider apertures used by comparatively bigger hermit crabs. This suggests that the occurrence of E. walshi was influenced by host size rather than host species. When looking at growth patterns, we found that the attached shell portion of E. walshi continued to be enlarged horizontally, while growth in shell height slowed at approximately 5.0 mm. The conspicuously flattened shell of E. walshi is considered as a growth pattern for adapting to the narrow space within the snail shell occupied by hermit crabs. Consistent with this idea, our comparison of shell growth patterns in 23 calyptraeid species showed that shell of E. walshi is the flattest in this family.},
}
@article {pmid30519652,
year = {2018},
author = {Kountche, BA and Novero, M and Jamil, M and Asami, T and Bonfante, P and Al-Babili, S},
title = {Effect of the strigolactone analogs methyl phenlactonoates on spore germination and root colonization of arbuscular mycorrhizal fungi.},
journal = {Heliyon},
volume = {4},
number = {11},
pages = {e00936},
doi = {10.1016/j.heliyon.2018.e00936},
pmid = {30519652},
issn = {2405-8440},
abstract = {Strigolactones (SLs), a novel class of plant hormones, are key regulator of plant architecture and mediator of biotic interactions in the rhizosphere. Root-released SLs initiate the establishment of arbuscular mycorrhizal (AM) symbiosis by inducing spore germination and hyphal branching in AM fungi (AMF). However, these compounds also trigger the germination of root parasitic weeds, paving the way for deleterious infestation. Availability of SLs is required for investigating of their functions and also for application in agriculture. However, natural SLs are difficult to synthesize due to their complex structure and cannot be isolated at large scale, as they are released at very low concentrations. Therefore, there is a need for synthetic SL analogs. Recently, we reported on the development of simple SL analogs, methyl phenlactonoates (MPs), which show high SL activity in plants. Here, we investigate the effect of MP1, MP3 and the widely used SL-analog GR24 on AMF spore germination and host root colonization. Our results show that MP1 and MP3 inhibit AMF spore germination, but promote the intra-radical root colonization, both more efficiently than GR24. These results indicate that field application of MP1 and MP3 does not have negative impact on mycorrhizal fungi. In conclusion, our data together with the previously reported simple synthesis, high activity in regulating plant architecture and inducing Striga seed germination, demonstrate the utility of MP1 and MP3 as for field application in combating root parasitic weeds by inducing germination in host's absence.},
}
@article {pmid30519411,
year = {2018},
author = {Bertoloni Meli, S and Bashey, F},
title = {Trade-off between reproductive and anti-competitor abilities in an insect-parasitic nematode-bacteria symbiosis.},
journal = {Ecology and evolution},
volume = {8},
number = {22},
pages = {10847-10856},
doi = {10.1002/ece3.4538},
pmid = {30519411},
issn = {2045-7758},
abstract = {Mutualistic symbionts can provide diverse benefits to their hosts and often supply key trait variation for host adaptation. The bacterial symbionts of entomopathogenic nematodes play a crucial role in successful colonization of and reproduction in the insect host. Additionally, these symbionts can produce a diverse array of antimicrobial compounds to deter within-host competitors. Natural isolates of the symbiont, Xenorhabdus bovienii, show considerable variation in their ability to target sympatric competitors via bacteriocins, which can inhibit the growth of sensitive Xenorhabdus strains. Both the bacteria and its nematode partner have been shown to benefit from bacteriocin production when within-host competition with a sensitive competitor occurs. Despite this benefit, several isolates of Xenorhabdus do not inhibit sympatric strains. To understand how this variation in allelopathy could be maintained, we tested the hypothesis that inhibiting isolates face a reproductive cost in the absence of competition. We tested this hypothesis by examining the reproductive success of inhibiting and non-inhibiting isolates coupled with their natural nematode host in a non-competitive context. We found that nematodes carrying non-inhibitors killed the insect host more rapidly and were more likely to successfully reproduce than nematodes carrying inhibitors. Lower reproductive success of inhibiting isolates was repeatable across nematode generations and across insect host species. However, no difference in insect mortality was observed between inhibiting and non-inhibiting isolates when bacteria were injected into insects without their nematode partners. Our results indicate a trade-off between the competitive and reproductive roles of symbionts, such that inhibiting isolates, which are better in the face of within-host competition, pay a reproductive cost in the absence of competition. Furthermore, our results support the hypothesis that symbiont variation within populations can be maintained through context-dependent fitness benefits conferred to their hosts. As such, our study offers novel insights into the selective forces maintaining variation within a single host-symbiont population and highlights the role of competition in mutualism evolution.},
}
@article {pmid30519408,
year = {2018},
author = {Burmester, EM and Breef-Pilz, A and Lawrence, NF and Kaufman, L and Finnerty, JR and Rotjan, RD},
title = {The impact of autotrophic versus heterotrophic nutritional pathways on colony health and wound recovery in corals.},
journal = {Ecology and evolution},
volume = {8},
number = {22},
pages = {10805-10816},
doi = {10.1002/ece3.4531},
pmid = {30519408},
issn = {2045-7758},
abstract = {For animals that harbor photosynthetic symbionts within their tissues, such as corals, the different relative contributions of autotrophy versus heterotrophy to organismal energetic requirements have direct impacts on fitness. This is especially true for facultatively symbiotic corals, where the balance between host-caught and symbiont-produced energy can be altered substantially to meet the variable demands of a shifting environment. In this study, we utilized a temperate coral-algal system (the northern star coral, Astrangia poculata, and its photosynthetic endosymbiont, Symbiodinium psygmophilum) to explore the impacts of nutritional sourcing on the host's health and ability to regenerate experimentally excised polyps. For fed and starved colonies, wound healing and total colony tissue cover were differentially impacted by heterotrophy versus autotrophy. There was an additive impact of positive nutritional and symbiotic states on a coral's ability to initiate healing, but a greater influence of symbiont state on the recovery of lost tissue at the lesion site and complete polyp regeneration. On the other hand, regardless of symbiont state, fed corals maintained a higher overall colony tissue cover, which also enabled more active host behavior (polyp extension) and endosymbiont behavior (photosynthetic ability of Symbiondinium). Overall, we determined that the impact of nutritional state and symbiotic state varied between biological functions, suggesting a diversity in energetic sourcing for each of these processes.},
}
@article {pmid30519403,
year = {2018},
author = {Bolin, LG and Benning, JW and Moeller, DA},
title = {Mycorrhizal interactions do not influence plant-herbivore interactions in populations of Clarkia xantiana ssp. xantiana spanning from center to margin of the geographic range.},
journal = {Ecology and evolution},
volume = {8},
number = {22},
pages = {10743-10753},
doi = {10.1002/ece3.4523},
pmid = {30519403},
issn = {2045-7758},
abstract = {Multispecies interactions can be important to the expression of phenotypes and in determining patterns of individual fitness in nature. Many plants engage in symbiosis with arbuscular mycorrhizal fungi (AMF), but the extent to which AMF modulate other species interactions remains poorly understood. We examined multispecies interactions among plants, AMF, and insect herbivores under drought stress using a greenhouse experiment and herbivore choice assays. The experiment included six populations of Clarkia xantiana (Onagraceae), which span a complex environmental gradient in the Southern Sierra Nevada of California. Clarkia xantiana's developing fruits are commonly attacked by grasshoppers at the end of the growing season, and the frequency of attack is more common in populations from the range center than range margin. We found that AMF negatively influenced all metrics of plant growth and reproduction across all populations, presumably because plants supplied carbon to AMF but did not benefit substantially from resources potentially supplied by the AMF. The fruits of plants infected with AMF did not differ from those without AMF in their resistance to grasshoppers. There was significant variation among populations in damage from herbivores but did not reflect the center-to-margin pattern of herbivory observed in the field. In sum, our results do not support the view that AMF interactions modulate plant-herbivore interactions in this system.},
}
@article {pmid30519234,
year = {2018},
author = {Temprano-Vera, F and Rodríguez-Navarro, DN and Acosta-Jurado, S and Perret, X and Fossou, RK and Navarro-Gómez, P and Zhen, T and Yu, D and An, Q and Buendía-Clavería, AM and Moreno, J and López-Baena, FJ and Ruiz-Sainz, JE and Vinardell, JM},
title = {Sinorhizobium fredii Strains HH103 and NGR234 Form Nitrogen Fixing Nodules With Diverse Wild Soybeans (Glycine soja) From Central China but Are Ineffective on Northern China Accessions.},
journal = {Frontiers in microbiology},
volume = {9},
number = {},
pages = {2843},
doi = {10.3389/fmicb.2018.02843},
pmid = {30519234},
issn = {1664-302X},
abstract = {Sinorhizobium fredii indigenous populations are prevalent in provinces of Central China whereas Bradyrhizobium species (Bradyrhizobium japonicum, B. diazoefficiens, B. elkanii, and others) are more abundant in northern and southern provinces. The symbiotic properties of different soybean rhizobia have been investigated with 40 different wild soybean (Glycine soja) accessions from China, Japan, Russia, and South Korea. Bradyrhizobial strains nodulated all the wild soybeans tested, albeit efficiency of nitrogen fixation varied considerably among accessions. The symbiotic capacity of S. fredii HH103 with wild soybeans from Central China was clearly better than with the accessions found elsewhere. S. fredii NGR234, the rhizobial strain showing the broadest host range ever described, also formed nitrogen-fixing nodules with different G. soja accessions from Central China. To our knowledge, this is the first report describing an effective symbiosis between S. fredii NGR234 and G. soja. Mobilization of the S. fredii HH103 symbiotic plasmid to a NGR234 pSym-cured derivative (strain NGR234C) yielded transconjugants that formed ineffective nodules with G. max cv. Williams 82 and G. soja accession CH4. By contrast, transfer of the symbiotic plasmid pNGR234a to a pSym-cured derivative of S. fredii USDA193 generated transconjugants that effectively nodulated G. soja accession CH4 but failed to nodulate with G. max cv. Williams 82. These results indicate that intra-specific transference of the S. fredii symbiotic plasmids generates new strains with unpredictable symbiotic properties, probably due to the occurrence of new combinations of symbiotic signals.},
}
@article {pmid30518840,
year = {2018},
author = {Tena, G},
title = {Symbiosis gatekeeper.},
journal = {Nature plants},
volume = {4},
number = {12},
pages = {982},
doi = {10.1038/s41477-018-0333-4},
pmid = {30518840},
issn = {2055-0278},
}
@article {pmid30518342,
year = {2018},
author = {Brottier, L and Chaintreuil, C and Simion, P and Scornavacca, C and Rivallan, R and Mournet, P and Moulin, L and Lewis, GP and Fardoux, J and Brown, SC and Gomez-Pacheco, M and Bourges, M and Hervouet, C and Gueye, M and Duponnois, R and Ramanankierana, H and Randriambanona, H and Vandrot, H and Zabaleta, M and DasGupta, M and D'Hont, A and Giraud, E and Arrighi, JF},
title = {A phylogenetic framework of the legume genus Aeschynomene for comparative genetic analysis of the Nod-dependent and Nod-independent symbioses.},
journal = {BMC plant biology},
volume = {18},
number = {1},
pages = {333},
doi = {10.1186/s12870-018-1567-z},
pmid = {30518342},
issn = {1471-2229},
support = {ANR-AeschyNod-14-CE19-0005-01//ANR/ ; },
abstract = {BACKGROUND: Among semi-aquatic species of the legume genus Aeschynomene, some have the property of being nodulated by photosynthetic Bradyrhizobium lacking the nodABC genes necessary for the synthesis of Nod factors. Knowledge of the specificities underlying this Nod-independent symbiosis has been gained from the model legume Aeschynomene evenia but our understanding remains limited due to the lack of comparative genetics with related taxa using a Nod factor-dependent process. To fill this gap, we combined different approaches to perform a thorough comparative analysis in the genus Aeschynomene.<br><br>RESULTS: This study significantly broadened previous taxon sampling, including in allied genera, in order to construct a comprehensive phylogeny. In the phylogenetic tree, five main lineages were delineated, including a novel lineage, the Nod-independent clade and another one containing a polytomy that comprised several Aeschynomene groups and all the allied genera. This phylogeny was matched with data on chromosome number, genome size and low-copy nuclear gene sequences to reveal the diploid species and a polytomy containing mostly polyploid taxa. For these taxa, a single allopolyploid origin was inferred and the putative parental lineages were identified. Finally, nodulation tests with different Bradyrhizobium strains revealed new nodulation behaviours and the diploid species outside of the Nod-independent clade were compared for their experimental tractability and genetic diversity.<br><br>CONCLUSIONS: The extended knowledge of the genetics and biology of the different lineages sheds new light of the evolutionary history of the genus Aeschynomene and they provide a solid framework to exploit efficiently the diversity encountered in Aeschynomene legumes. Notably, our backbone tree contains all the species that are diploid and it clarifies the genetic relationships between the Nod-independent clade and the Nod-dependent lineages. This study enabled the identification of A. americana and A. patula as the most suitable species to undertake a comparative genetic study of the Nod-independent and Nod-dependent symbioses.},
}
@article {pmid30508325,
year = {2018},
author = {Hsiao, CC and Sieber, S and Georgiou, A and Bailly, A and Emmanouilidou, D and Carlier, A and Eberl, L and Gademann, K},
title = {Synthesis and Biological Evaluation of the Novel Growth Inhibitor Streptol Glucoside, Isolated from an Obligate Plant Symbiont.},
journal = {Chemistry (Weinheim an der Bergstrasse, Germany)},
volume = {},
number = {},
pages = {},
doi = {10.1002/chem.201805693},
pmid = {30508325},
issn = {1521-3765},
abstract = {The plant Psychotria kirkii hosts an obligatory bacterial symbiont, Candidatus Burkholderia kirkii, in nodules on their leaves. Recently, a glucosylated derivative of (+)-streptol, (+)-streptol glucoside, was isolated from the nodulated leaves and was found to possess a plant growth inhibitory activity. To establish a structure activity relationship study, a convergent strategy was developed to obtain several pseudosugars from a single synthetic precursor. Furthermore, the glucosylation of streptol was investigated in detail and conditions affording specifically the alpha or beta glucosidic anomer were identified. Although (+)-streptol was the most active compound, its concentration in P. kirkii plant leaves extract was approximately 10 fold lower than that of (+)-streptol glucoside. These results provide compelling evidence that the glucosylation of (+)-streptol protects the plant host against the growth inhibitory effect of the compound, which might constitute a molecular cornerstone for this successful plant-bacteria symbiosis.},
}
@article {pmid30506600,
year = {2018},
author = {Wasilko, NP and Larios-Valencia, J and Steingard, CH and Nunez, BM and Verma, SC and Miyashiro, T},
title = {Sulfur availability for Vibrio fischeri growth during symbiosis establishment depends on biogeography within the squid light organ.},
journal = {Molecular microbiology},
volume = {},
number = {},
pages = {},
doi = {10.1111/mmi.14177},
pmid = {30506600},
issn = {1365-2958},
abstract = {The fitness of host-associated microbes depends on their ability to access nutrients in vivo. Identifying these mechanisms is significant for understanding how microbes have evolved to fill specific ecological niches within a host. Vibrio fischeri is a bioluminescent bacterium that colonizes and proliferates within the light organ of the Hawaiian bobtail squid, which provides an opportunity to study how bacteria grow in vivo. Here, the transcription factor CysB is shown to be necessary for V. fischeri both to grow on several sulfur sources in vitro and to establish symbiosis with juvenile squid. CysB is also found to regulate several genes involved in sulfate assimilation and to contribute to the growth of V. fischeri on cystine, which is the oxidized form of cysteine. A mutant that grows on cystine but not sulfate could establish symbiosis, suggesting that V. fischeri acquires nutrients related to this compound within the host. Finally, CysB-regulated genes are shown to be differentially expressed among the V. fischeri populations occupying the various colonization sites found within the light organ. Together, these results suggest the biogeography of V. fischeri populations within the squid light organ impacts the physiology of this symbiotic bacterium in vivo through CysB-dependent gene regulation. This article is protected by copyright. All rights reserved.},
}
@article {pmid30505297,
year = {2018},
author = {Pardo-De la Hoz, CJ and Magain, N and Lutzoni, F and Goward, T and Restrepo, S and Miadlikowska, J},
title = {Contrasting Symbiotic Patterns in Two Closely Related Lineages of Trimembered Lichens of the Genus Peltigera.},
journal = {Frontiers in microbiology},
volume = {9},
number = {},
pages = {2770},
doi = {10.3389/fmicb.2018.02770},
pmid = {30505297},
issn = {1664-302X},
abstract = {Species circumscription is key to the characterization of patterns of specificity in symbiotic systems at a macroevolutionary scale. Here, a worldwide phylogenetic framework was used to assess the biodiversity and symbiotic patterns of association among partners in trimembered lichens from the genus Peltigera, section Chloropeltigera. We sequenced six loci of the main fungal partner and performed species discovery and validation analyses to establish putative species boundaries. Single locus phylogenies were used to establish the identity of both photobionts, Nostoc (cyanobacterium) and Coccomyxa (green alga). Distribution and specificity patterns were compared to the closely related clade, section Peltidea, which includes mainly Peltigera species with trimembered thalli. For section Chloropeltigera, eight fungal species (including five newly delimited putative species) were found in association with nine Nostoc phylogroups and two Coccomyxa species. In contrast, eight fungal species (including three newly delimited putative species) in section Peltidea were found in association with only four Nostoc phylogroups and the same two Coccomyxa species as for section Chloropeltigera. This difference in cyanobiont biodiversity between these two sections can potentially be explained by a significantly higher frequency of sexual reproductive structures in species from section Chloropeltigera compared to section Peltidea. Therefore, horizontal transmission of the cyanobiont might be more prevalent in Chloropeltigera species, while vertical transmission might be more common in Peltidea species. All Peltigera species in section Chloropeltigera are generalists in their association with Nostoc compared to more specialized Peltigera species in section Peltidea. Constrained distributions of Peltigera species that associate strictly with one species of green algae (Coccomyxa subellipsoidea) indicate that the availability of the green alga and the specificity of the interaction might be important factors limiting geographic ranges of trimembered Peltigera, in addition to constraints imposed by their interaction with Nostoc partners and by climatic factors.},
}
@article {pmid30504321,
year = {2018},
author = {Nazha, A},
title = {The MDS genomics-prognosis symbiosis.},
journal = {Hematology. American Society of Hematology. Education Program},
volume = {2018},
number = {1},
pages = {270-276},
doi = {10.1182/asheducation-2018.1.270},
pmid = {30504321},
issn = {1520-4383},
abstract = {Myelodysplastic syndromes (MDS) are clonal disorders characterized by the accumulation of complex genomic abnormalities that define disease phenotype, prognosis, and the risk of transformation to acute myeloid leukemia. The clinical manifestations and overall outcomes of MDS are very heterogeneous with an overall survival that can be measured in years for some patients to a few months for others. Prognostic scoring systems are important staging tools that aid physicians in their treatment recommendations and decision-making and can help patients understand their disease trajectory and expectations. Several scoring systems have been developed in MDS with the International Prognostic Scoring System and its revised version, the most widely used systems in clinical practice and trial eligibility. These models and others use mainly clinical variables that are obtained from bone marrow biopsy and peripheral blood measurements. Adding molecular data to current models may improve its predictive power but the ultimate method to incorporate this information remains a work in progress. Novel methods to develop a personalized prediction model that provides outcomes that are specific for a patient are currently under way and may change how we think about risk stratification in MDS patients in the future.},
}
@article {pmid30504145,
year = {2018},
author = {Tokuda, G and Mikaelyan, A and Fukui, C and Matsuura, Y and Watanabe, H and Fujishima, M and Brune, A},
title = {Fiber-associated spirochetes are major agents of hemicellulose degradation in the hindgut of wood-feeding higher termites.},
journal = {Proceedings of the National Academy of Sciences of the United States of America},
volume = {},
number = {},
pages = {},
doi = {10.1073/pnas.1810550115},
pmid = {30504145},
issn = {1091-6490},
abstract = {Symbiotic digestion of lignocellulose in wood-feeding higher termites (family Termitidae) is a two-step process that involves endogenous host cellulases secreted in the midgut and a dense bacterial community in the hindgut compartment. The genomes of the bacterial gut microbiota encode diverse cellulolytic and hemicellulolytic enzymes, but the contributions of host and bacterial symbionts to lignocellulose degradation remain ambiguous. Our previous studies of Nasutitermes spp. documented that the wood fibers in the hindgut paunch are consistently colonized not only by uncultured members of Fibrobacteres, which have been implicated in cellulose degradation, but also by unique lineages of Spirochaetes. Here, we demonstrate that the degradation of xylan, the major component of hemicellulose, is restricted to the hindgut compartment, where it is preferentially hydrolyzed over cellulose. Metatranscriptomic analysis documented that the majority of glycoside hydrolase (GH) transcripts expressed by the fiber-associated bacterial community belong to family GH11, which consists exclusively of xylanases. The substrate specificity was further confirmed by heterologous expression of the gene encoding the predominant homolog. Although the most abundant transcripts of GH11 in Nasutitermes takasagoensis were phylogenetically placed among their homologs of Firmicutes, immunofluorescence microscopy, compositional binning of metagenomics contigs, and the genomic context of the homologs indicated that they are encoded by Spirochaetes and were most likely obtained by horizontal gene transfer among the intestinal microbiota. The major role of spirochetes in xylan degradation is unprecedented and assigns the fiber-associated Treponema clades in the hindgut of wood-feeding higher termites a prominent part in the breakdown of hemicelluloses.},
}
@article {pmid30503958,
year = {2018},
author = {Shaaban, M and Elgaml, A and Habib, EE},
title = {Biotechnological applications of quorum sensing inhibition as novel therapeutic strategies for multidrug resistant pathogens.},
journal = {Microbial pathogenesis},
volume = {},
number = {},
pages = {},
doi = {10.1016/j.micpath.2018.11.043},
pmid = {30503958},
issn = {1096-1208},
abstract = {High incidence of antibiotic resistance among bacterial clinical isolates necessitates the discovery of new targets for inhibition of microbial pathogenicity without stimulation of microbial resistance. This could be achieved by targeting virulence determinants which cause host damage and disease. Many pathogenic bacteria elaborate signaling molecules for cellular communication. This signaling system is named quorum sensing system (QS), and it is contingent on the bacterial population density and mediated by signal molecules called pheromones or autoinducers (AIs). Bacteria utilize QS to regulate activities and behaviors including competence, conjugation, symbiosis, virulence, motility, sporulation, antibiotic production, and biofilm formation. Hence, targeting bacterial communicating signals and suppression of QS exhibit a fundamental approach for competing microbial communication. In this review, we illustrate the common up to date approaches to utilize QS circuits in pathogenic bacteria, including Vibrio fischeri, Pseudomonas aeruginosa, Escherichia coli and Acinetobacter baumannii, as novel therapeutic targets.},
}
@article {pmid30502748,
year = {2019},
author = {Dargahi, N and Johnson, J and Donkor, O and Vasiljevic, T and Apostolopoulos, V},
title = {Immunomodulatory effects of probiotics: Can they be used to treat allergies and autoimmune diseases?.},
journal = {Maturitas},
volume = {119},
number = {},
pages = {25-38},
doi = {10.1016/j.maturitas.2018.11.002},
pmid = {30502748},
issn = {1873-4111},
abstract = {As a person ages, physiological, immunological and gut microbiome changes collectively result in an array of chronic conditions. According to the 'hygiene hypothesis' the increasing prevalence of immune-mediated disorders may be related to intestinal dysbiosis, leading to immune dysfunction and associated conditions such as eczema, asthma, allergies and autoimmune diseases. Beneficial probiotic bacteria can be utilized by increasing their abundance within the gastrointestinal lumen, which in turn will modulate immune cells, such as, T helper (Th)-1, Th2, Th17, regulatory T (Treg) cells and B cells, which have direct relevance to human health and the pathogenesis of immune disorders. Here, we describe the cross-talk between probiotics and the gastrointestinal immune system, and their effects in relation to inflammatory bowel disease, multiple sclerosis, allergies and atopic dermatitis.},
}
@article {pmid30502467,
year = {2018},
author = {Wang, H and Tang, W and Zhang, R and Ding, S},
title = {Analysis of enzyme activity, antibacterial activity, antiparasitic activity and physico-chemical stability of skin mucus derived from Amphiprion clarkii.},
journal = {Fish &amp; shellfish immunology},
volume = {},
number = {},
pages = {},
doi = {10.1016/j.fsi.2018.11.066},
pmid = {30502467},
issn = {1095-9947},
abstract = {Recently, mucosal surfaces, especially fish skin and its secreted mucus, have attracted significant interest from immunologists. Amphiprion clarkii, a member of the family Pomacentridae, lives symbiosis with sea anemones and has a good resistance to common seawater bacterial diseases and parasites owing to the protection from its abundant skin mucus. In the present work, the activity of immune-related enzymes (lysozyme, protease, antiprotease, cathepsin B, alkaline phosphatase and peroxidase), the antibacterial activity against two Gram-positive bacteria and five Gram-negative bacteria, the antiparasitic activity against the pathogen of marine white spot disease (Cryptocaryon irritans theronts) and the physico-chemical stability (to pH and heat) of the skin mucus of A. clarkii were analysed. The results showed that the levels of lysozyme and peroxidase were very similar (from 2 to 4 U mg-1 protein). However, cathepsin B was detected of 63.32 U mg-1 protein and alkaline phosphatase was only 0.12 U mg-1 protein. Moreover, protease showed a higher percentage of activity than antiprotease. A. clarkii skin mucus showed a strong antibacterial activity against Gram-negative bacteria, particularly against Aeromonas hydrophila and Vibrio parahaemolyticus but showed no effect on Gram-positive bacteria at the tested concentrations. The bactericidal activity functioned within a short time in a distinct time- and dose-dependent manner. SEM showed that after treated with A. clarkii skin mucus, the V. parahaemolyticus cells distorted and piled together, and the filaments appeared and became into cotton-shaped or quasi-honeycomb texture to adhere cells. Meanwhile, A. clarkii skin mucus showed an apparent antiparasitic activity against C. irritans theronts with a distinct dose- and time-dependent relationship. LM and SEM observation showed that after treated with skin mucus, the theronts quickly stopped their swimming and cilia movement, cells beacme rounded, cilia shed, small bubbles formed on the surface, cell nucleolus enlarged, cytoskeleton deformed, cell membranes ruptured and cell content leaked out. Antibacterial activity was not affected by 30-90 °C heat treatment but was slightly suppressed by 100 °C. In the pH treatment groups, antibacterial activity was not affected by the moderate pH treatment of 5.0-8.0, and slightly suppressed by weak acid and weak base. Therefore, we speculated that the skin mucus of A. clarkii might be a potential source of novel antibacterial and antiparasitic components for fish or human health-related applications. This study broadened our understanding of the role of skin mucus in the innate immune system and provided a basis for the further isolation and purification of active substances.},
}
@article {pmid30517276,
year = {2018},
author = {Fuente, AL and Urcuyo, RJ and Vega, GH},
title = {Protists and other organisms on a minute snail periostracum.},
journal = {Brazilian journal of biology = Revista brasleira de biologia},
volume = {},
number = {},
pages = {},
doi = {10.1590/1519-6984.186837},
pmid = {30517276},
issn = {1678-4375},
abstract = {Since the foundation of the Malacological Center in 1980, Universidad Centro Americana (UCA), Managua-Nicaragua, has been monitoring and collecting the marine, terrestrial, fluvial and lake mollusk population of the country. Many specimens have been photographed by Scanning Electronic Microscope (SEM), and in one of these, observation of the hairy periostracum reveals a seemingly thriving population of minute protists in possible symbiosis with their host. Adequate magnification and comparison with previous studies allowed the determination of these hosts as diatoms, testaceous amoebae, yeast, phacus, spores and other undetermined organisms which occur in tropical forests on rocks, trees and leaves. Here illustrated are diatoms and other organisms detected for the first time on the periostracum of a tropical rainforest mollusk.},
}
@article {pmid30515182,
year = {2018},
author = {Gil-Martínez, M and López-García, Á and Domínguez, MT and Navarro-Fernández, CM and Kjøller, R and Tibbett, M and Marañón, T},
title = {Ectomycorrhizal Fungal Communities and Their Functional Traits Mediate Plant-Soil Interactions in Trace Element Contaminated Soils.},
journal = {Frontiers in plant science},
volume = {9},
number = {},
pages = {1682},
doi = {10.3389/fpls.2018.01682},
pmid = {30515182},
issn = {1664-462X},
abstract = {There is an increasing consensus that microbial communities have an important role in mediating ecosystem processes. Trait-based ecology predicts that the impact of the microbial communities on ecosystem functions will be mediated by the expression of their traits at community level. The link between the response of microbial community traits to environmental conditions and its effect on plant functioning is a gap in most current microbial ecology studies. In this study, we analyzed functional traits of ectomycorrhizal fungal species in order to understand the importance of their community assembly for the soil-plant relationships in holm oak trees (Quercus ilex subsp. ballota) growing in a gradient of exposure to anthropogenic trace element (TE) contamination after a metalliferous tailings spill. Particularly, we addressed how the ectomycorrhizal composition and morphological traits at community level mediate plant response to TE contamination and its capacity for phytoremediation. Ectomycorrhizal fungal taxonomy and functional diversity explained a high proportion of variance of tree functional traits, both in roots and leaves. Trees where ectomycorrhizal fungal communities were dominated by the abundant taxa Hebeloma cavipes and Thelephora terrestris showed a conservative root economics spectrum, while trees colonized by rare taxa presented a resource acquisition strategy. Conservative roots presented ectomycorrhizal functional traits characterized by high rhizomorphs formation and low melanization which may be driven by resource limitation. Soil-to-root transfer of TEs was explained substantially by the ectomycorrhizal fungal species composition, with the highest transfer found in trees whose roots were colonized by Hebeloma cavipes. Leaf phosphorus was related to ectomycorrhizal species composition, specifically higher leaf phosphorus was related to the root colonization by Thelephora terrestris. These findings support that ectomycorrhizal fungal community composition and their functional traits mediate plant performance in metal-contaminated soils, and have a high influence on plant capacity for phytoremediation of contaminants. The study also corroborates the overall effects of ectomycorrhizal fungi on ecosystem functioning through their mediation over the plant economics spectrum.},
}
@article {pmid30513975,
year = {2018},
author = {Nath, A and Molnár, MA and Csighy, A and Kőszegi, K and Galambos, I and Huszár, KP and Koris, A and Vatai, G},
title = {Biological Activities of Lactose-Based Prebiotics and Symbiosis with Probiotics on Controlling Osteoporosis, Blood-Lipid and Glucose Levels.},
journal = {Medicina (Kaunas, Lithuania)},
volume = {54},
number = {6},
pages = {},
doi = {10.3390/medicina54060098},
pmid = {30513975},
issn = {1648-9144},
abstract = {Lactose-based prebiotics are synthesized by enzymatic- or microbial- biotransformation of lactose and have unique functional values. In this comprehensive review article, the biochemical mechanisms of controlling osteoporosis, blood-lipid, and glucose levels by lactose-based prebiotics and symbiosis with probiotics are reported along with the results of clinical investigations. Interaction between lactose-based prebiotics and probiotics reduces osteoporosis by (a) transforming insoluble inorganic salts to soluble and increasing their absorption to gut wall; (b) maintaining and protecting mineral absorption surface in the intestine; (c) increasing the expression of calcium-binding proteins in the gut wall; (d) remodeling osteoclasts and osteoblasts formation; (e) releasing bone modulating factors; and (f) degrading mineral complexing phytic acid. Lactose-based prebiotics with probiotics control lipid level in the bloodstream and tissue by (a) suppressing the expressions of lipogenic- genes and enzymes; (b) oxidizing fatty acids in muscle, liver, and adipose tissue; (c) binding cholesterol with cell membrane of probiotics and subsequent assimilation by probiotics; (d) enzymatic-transformations of bile acids; and (e) converting cholesterol to coprostanol and its defecation. Symbiosis of lactose-based prebiotics with probiotics affect plasma glucose level by (a) increasing the synthesis of gut hormones plasma peptide-YY, glucagon-like peptide-1 and glucagon-like peptide-2 from entero-endocrine L-cells; (b) altering glucose assimilation and metabolism; (c) suppressing systematic inflammation; (d) reducing oxidative stress; and (e) producing amino acids. Clinical investigations show that lactose-based prebiotic galacto-oligosaccharide improves mineral absorption and reduces hyperlipidemia. Another lactose-based prebiotic, lactulose, improves mineral absorption, and reduces hyperlipidemia and hyperglycemia. It is expected that this review article will be of benefit to food technologists and medical practitioners.},
}
@article {pmid30511528,
year = {2018},
author = {Chen, S and Shao, G and Shao, F and Zhang, M},
title = {[Diffusion-weighted imaging texture features in differentiation of malignant from benign nonpalpable breast lesions for patients with microcalcifications-only in mammography].},
journal = {Zhejiang da xue xue bao. Yi xue ban = Journal of Zhejiang University. Medical sciences},
volume = {47},
number = {4},
pages = {400-404},
pmid = {30511528},
issn = {1008-9292},
abstract = {OBJECTIVE: To evaluate the application of MR diffusion-weighted imaging(DWI) texture features in differentiation of malignant from benign nonpalpable breast lesion for patients with microcalcifications-only in mammography.<br><br>METHODS: The clinical and MR-DWI data of 61 patients with microcalcifications, who underwent three-dimensional positioning of breast X-ray wire from October 2012 to December 2015 in Zhejiang Cancer Hospital, were retrospectively analyzed, including 38 patients with malignant lesions and 23 patients with benign lesions. Two radiologists independently drew the regions of interest (ROI) on DWI for image segmentation, and 6 histogram features and 16 grayscale symbiosis matrix (GLCM) texture features were extracted on each ROI. The random forest algorithm was applied to select the features and built the classification model. The leave-one-out cross-validation (LOOCV) was used to validate the classifier, and the performance of the classifier was evaluated by ROC curve.<br><br>RESULTS: Six features were selected, including histogram features of mean, variance, skewness, entropy, as well as contrast (0°) and correlation (45°) in GLCM. The histogram features of mean, variance, skewness and entropy were significantly different between the benign and malignant breast lesions (all P<0.05). The AUC of the model was 0.76, and the diagnostic accuracy, sensitivity and specificity were 77.05%, 84.21% and 65.21%, respectively.<br><br>CONCLUSIONS: The texture feature analysis of DWI can improve the diagnostic accuracy of differentiating benign and malignant breast nonpalpable lesions with microcalcifications-only in mammography. Histogram features of mean, variance, skewness, entropy of DWI may be used as important imaging markers.},
}
@article {pmid30510528,
year = {2018},
author = {Hernandez, AE and Claussenius-Kalman, HL and Ronderos, J and Vaughn, KA},
title = {Symbiosis, Parasitism and Bilingual Cognitive Control: A Neuroemergentist Perspective.},
journal = {Frontiers in psychology},
volume = {9},
number = {},
pages = {2171},
doi = {10.3389/fpsyg.2018.02171},
pmid = {30510528},
issn = {1664-1078},
abstract = {Interest in the intersection between bilingualism and cognitive control and accessibility to neuroimaging methods has resulted in numerous studies with a variety of interpretations of the bilingual cognitive advantage. Neurocomputational Emergentism (or Neuroemergentism for short) is a new framework for understanding this relationship between bilingualism and cognitive control. This framework considers Emergence, in which two small elements are recombined in an interactive manner, yielding a non-linear effect. Added to this is the notion that Emergence can be captured in neural systems using computationally inspired models. This review poses that bilingualism and cognitive control, as examined through the Neuroemergentist framework, are interwoven through development and involve the non-linear growth of cognitive processing encompassing brain areas that combine and recombine, in symbiotic and parasitic ways, in order to handle more complex types of processing. The models that have sought to explain the neural substrates of bilingual cognitive differences will be discussed with a reinterpretation of the entire bilingual cognitive advantage within a Neuroemergentist framework incorporating its neural bases. It will conclude by discussing how this new Neuroemergentist approach alters our view of the effects of language experience on cognitive control. Avenues to move beyond the simple notion of a bilingual advantage or lack thereof will be proposed.},
}
@article {pmid30500814,
year = {2018},
author = {Lopes, LE and Waldis, SJ and Terrell, SM and Lindgren, KA and Charkoudian, LK},
title = {Vibrant symbiosis: Achieving reciprocal science outreach through biological art.},
journal = {PLoS biology},
volume = {16},
number = {11},
pages = {e3000061},
doi = {10.1371/journal.pbio.3000061},
pmid = {30500814},
issn = {1545-7885},
abstract = {Scientific outreach efforts traditionally involve formally trained scientists teaching the general public about the methods, significance, and excitement of science. We recently experimented with an alternative &quot;symbiotic outreach&quot; model that prioritizes building a reciprocal relationship between formally trained and &quot;outsider&quot; scientists to facilitate active two-way communication. Herein, we present the results of our outreach effort involving college students and adults with intellectual and developmental disabilities working together to make biological and multimedia art. By discussing the steps others can take to cultivate reciprocal outreach within their local communities, we hope to lower the barrier for widespread adoption of similar approaches and ultimately to decrease the gap between formally trained scientists and the general public.},
}
@article {pmid30497879,
year = {2018},
author = {Tsaftaris, SA and Scharr, H},
title = {Sharing the Right Data Right: A Symbiosis with Machine Learning.},
journal = {Trends in plant science},
volume = {},
number = {},
pages = {},
doi = {10.1016/j.tplants.2018.10.016},
pmid = {30497879},
issn = {1878-4372},
abstract = {In 2014 plant phenotyping research was not benefiting from the machine learning (ML) revolution because appropriate data were lacking. We report the success of the first open-access dataset suitable for ML in image-based plant phenotyping suitable for machine learning, fuelling a true interdisciplinary symbiosis, increased awareness, and steep performance improvements on key phenotyping tasks.},
}
@article {pmid30489239,
year = {2018},
author = {Khasa, R and Vaidya, A and Vrati, S and Kalia, M},
title = {Membrane trafficking RNA interference screen identifies a crucial role of the clathrin endocytic pathway and ARP2/3 complex for Japanese encephalitis virus infection in HeLa cells.},
journal = {The Journal of general virology},
volume = {},
number = {},
pages = {},
doi = {10.1099/jgv.0.001182},
pmid = {30489239},
issn = {1465-2099},
abstract = {Japanese encephalitis virus (JEV), a mosquito-borne flavivirus, is one of the leading global causes of virus-induced encephalitis. The infectious life-cycle of viruses is heavily dependent on the host membrane trafficking network. Here, we have performed a RNA-interference-based screen using a siRNA panel targeting 136 membrane trafficking proteins to identify the key regulators of JEV infection in HeLa cells. We identified 35 proteins whose siRNA depletion restricts JEV replication by over twofold. We observe that JEV infection in HeLa cells is largely dependent on components of the clathrin-mediated endocytic (CME) pathway. Proteins involved in actin-filament-based processes, specifically CDC42 and members of the ARP2/3 complex are crucial for establishment of infection. Pharmacological pertubations of actin polymerization, a small molecule inhibitor of actin nucleation by the ARP2/3 complex - CK-548 - and the inhibitor of neural Wiskott-Aldrich syndrome proteins- Wiskostatin- inhibited JEV replication, highlighting the important role of the dynamic actin network. Other proteins involved in cargo-recognition for CME and endomembrane system organization were also validated as essential host factors for virus replication.},
}
@article {pmid30488371,
year = {2018},
author = {Paulitsch, F and Klepa, MS and da Silva, AR and do Carmo, MRB and Dall'Agnol, RF and Delamuta, JRM and Hungria, M and da Silva Batista, JS},
title = {Phylogenetic diversity of rhizobia nodulating native Mimosa gymnas grown in a South Brazilian ecotone.},
journal = {Molecular biology reports},
volume = {},
number = {},
pages = {},
doi = {10.1007/s11033-018-4506-z},
pmid = {30488371},
issn = {1573-4978},
support = {465133/2014-4//Conselho Nacional de Desenvolvimento Científico e Tecnológico/ ; UEPG 09/2016//Fundação Araucária/ ; N/A//Coordenação de Aperfeiçoamento de Pessoal de Nível Superior/ ; },
abstract = {Floristic surveys performed in &quot;Campos Gerais&quot; (Paraná, Brazil), an ecotone of Mata Atlântica and Cerrado biomes, highlights the richness and relative abundance of the family Fabaceae and point out the diversity and endemism of Mimosa spp. Our study reports the genetic diversity of rhizobia isolated from root nodules of native/endemic Mimosa gymnas Barneby in three areas of Guartelá State Park, an important conservation unit of &quot;Campos Gerais&quot;. Soils of the sample areas were characterized as sandy, acid, poor in nutrients and organic matter. The genetic variability among the isolates was revealed by BOX-PCR genomic fingerprinting. Phylogeny based on 16S rRNA gene grouped the strains in a large cluster including Paraburkholderia nodosa and P. bannensis, while recA-gyrB phylogeny separated the strains in two groups: one including P. nodosa and the other without any described Paraburkholderia species. MLSA confirmed the separate position of this second group of strains within the genus Paraburkholderia and the nucleotide identity of the five concatened housekeeping genes was 95.9% in relation to P. nodosa BR 3437T. Phylogram based on symbiosis-essential nodC gene was in agreement with 16S rRNA analysis. Our molecular phylogenetic analysis support that Paraburkholderia are the main symbionts of native Mimosa in specific edaphic conditions found in South America and reveal the importance of endemic/native leguminous plants as reservoirs of novel rhizobial species.},
}
@article {pmid30487315,
year = {2018},
author = {Matthews, JL and Oakley, CA and Lutz, A and Hillyer, KE and Roessner, U and Grossman, AR and Weis, VM and Davy, SK},
title = {Partner switching and metabolic flux in a model cnidarian-dinoflagellate symbiosis.},
journal = {Proceedings. Biological sciences},
volume = {285},
number = {1892},
pages = {},
doi = {10.1098/rspb.2018.2336},
pmid = {30487315},
issn = {1471-2954},
abstract = {Metabolite exchange is fundamental to the viability of the cnidarian-Symbiodiniaceae symbiosis and survival of coral reefs. Coral holobiont tolerance to environmental change might be achieved through changes in Symbiodiniaceae species composition, but differences in the metabolites supplied by different Symbiodiniaceae species could influence holobiont fitness. Using 13C stable-isotope labelling coupled to gas chromatography-mass spectrometry, we characterized newly fixed carbon fate in the model cnidarian Exaiptasia pallida (Aiptasia) when experimentally colonized with either native Breviolum minutum or non-native Durusdinium trenchii Relative to anemones containing B. minutum, D. trenchii-colonized hosts exhibited a 4.5-fold reduction in 13C-labelled glucose and reduced abundance and diversity of 13C-labelled carbohydrates and lipogenesis precursors, indicating symbiont species-specific modifications to carbohydrate availability and lipid storage. Mapping carbon fate also revealed significant alterations to host molecular signalling pathways. In particular, D. trenchii-colonized hosts exhibited a 40-fold reduction in 13C-labelled scyllo-inositol, a potential interpartner signalling molecule in symbiosis specificity. 13C-labelling also highlighted differential antioxidant- and ammonium-producing pathway activities, suggesting physiological responses to different symbiont species. Such differences in symbiont metabolite contribution and host utilization may limit the proliferation of stress-driven symbioses; this contributes valuable information towards future scenarios that select in favour of less-competent symbionts in response to environmental change.},
}
@article {pmid30483906,
year = {2018},
author = {Chan, CK and Rosic, N and Lorenc, MT and Visendi, P and Lin, M and Kaniewska, P and Ferguson, BJ and Gresshoff, PM and Batley, J and Edwards, D},
title = {A differential k-mer analysis pipeline for comparing RNA-Seq transcriptome and meta-transcriptome datasets without a reference.},
journal = {Functional &amp; integrative genomics},
volume = {},
number = {},
pages = {},
doi = {10.1007/s10142-018-0647-3},
pmid = {30483906},
issn = {1438-7948},
abstract = {Next-generation DNA sequencing technologies, such as RNA-Seq, currently dominate genome-wide gene expression studies. A standard approach to analyse this data requires mapping sequence reads to a reference and counting the number of reads which map to each gene. However, for many transcriptome studies, a suitable reference genome is unavailable, especially for meta-transcriptome studies which assay gene expression from mixed populations of organisms. Where a reference is unavailable, it is possible to generate a reference by the de novo assembly of the sequence reads. However, the high cost of generating high-coverage data for de novo assembly hinders this approach and more importantly the accurate assembly of such data is challenging, especially for meta-transcriptome data, and resulting assemblies frequently suffer from collapsed regions or chimeric sequences. As an alternative to the standard reference mapping approach, we have developed a k-mer-based analysis pipeline (DiffKAP) to identify differentially expressed reads between RNA-Seq datasets without the requirement for a reference. We compared the DiffKAP approach with the traditional Tophat/Cuffdiff method using RNA-Seq data from soybean, which has a suitable reference genome. We subsequently examined differential gene expression for a coral meta-transcriptome where no reference is available, and validated the results using qRT-PCR. We conclude that DiffKAP is an accurate method to study differential gene expression in complex meta-transcriptomes without the requirement of a reference genome.},
}
@article {pmid30483280,
year = {2018},
author = {Gagic, M and Faville, MJ and Zhang, W and Forester, NT and Rolston, MP and Johnson, RD and Ganesh, S and Koolaard, JP and Easton, HS and Hudson, D and Johnson, LJ and Moon, CD and Voisey, CR},
title = {Seed Transmission of Epichloë Endophytes in Lolium perenne Is Heavily Influenced by Host Genetics.},
journal = {Frontiers in plant science},
volume = {9},
number = {},
pages = {1580},
doi = {10.3389/fpls.2018.01580},
pmid = {30483280},
issn = {1664-462X},
abstract = {Vertical transmission of symbiotic Epichloë endophytes from host grasses into progeny seed is the primary mechanism by which the next generation of plants is colonized. This process is often imperfect, resulting in endophyte-free seedlings which may have poor ecological fitness if the endophyte confers protective benefits to its host. In this study, we investigated the influence of host genetics and environment on the vertical transmission of Epichloë festucae var. lolii strain AR37 in the temperate forage grass Lolium perenne. The efficiency of AR37 transmission into the seed of over 500 plant genotypes from five genetically diverse breeding populations was determined. In Populations I-III, which had undergone previous selection for high seed infection by AR37, mean transmission was 88, 93, and 92%, respectively. However, in Populations IV and V, which had not undergone previous selection, mean transmission was 69 and 70%, respectively. The transmission values, together with single-nucleotide polymorphism data obtained using genotyping-by-sequencing for each host, was used to develop a genomic prediction model for AR37 seed transmission. The predictive ability of the model was estimated at r = 0.54. While host genotype contributed greatly to differences in AR37 seed transmission, undefined environmental variables also contributed significantly to seed transmission across different years and geographic locations. There was evidence for a small host genotype-by-environment effect; however this was less pronounced than genotype or environment alone. Analysis of endophyte infection levels in parent plants within Populations I and IV revealed a loss of endophyte infection over time in Population IV only. This population also had lower average tiller infection frequencies than Population I, suggesting that AR37 failed to colonize all the daughter tillers and therefore seeds. However, we also observed that infection of seed by AR37 may fail during or after initiation of floral development from plants where all tillers remained endophyte-infected over time. While the effects of environment and host genotype on fungal endophyte transmission have been evaluated previously, this is the first study that quantifies the relative impacts of host genetics and environment on endophyte vertical transmission.},
}
@article {pmid30483277,
year = {2018},
author = {Mohammadi-Dehcheshmeh, M and Niazi, A and Ebrahimi, M and Tahsili, M and Nurollah, Z and Ebrahimi Khaksefid, R and Ebrahimi, M and Ebrahimie, E},
title = {Unified Transcriptomic Signature of Arbuscular Mycorrhiza Colonization in Roots of Medicago truncatula by Integration of Machine Learning, Promoter Analysis, and Direct Merging Meta-Analysis.},
journal = {Frontiers in plant science},
volume = {9},
number = {},
pages = {1550},
doi = {10.3389/fpls.2018.01550},
pmid = {30483277},
issn = {1664-462X},
abstract = {Plant root symbiosis with Arbuscular mycorrhizal (AM) fungi improves uptake of water and mineral nutrients, improving plant development under stressful conditions. Unraveling the unified transcriptomic signature of a successful colonization provides a better understanding of symbiosis. We developed a framework for finding the transcriptomic signature of Arbuscular mycorrhiza colonization and its regulating transcription factors in roots of Medicago truncatula. Expression profiles of roots in response to AM species were collected from four separate studies and were combined by direct merging meta-analysis. Batch effect, the major concern in expression meta-analysis, was reduced by three normalization steps: Robust Multi-array Average algorithm, Z-standardization, and quartiling normalization. Then, expression profile of 33685 genes in 18 root samples of Medicago as numerical features, as well as study ID and Arbuscular mycorrhiza type as categorical features, were mined by seven models: RELIEF, UNCERTAINTY, GINI INDEX, Chi Squared, RULE, INFO GAIN, and INFO GAIN RATIO. In total, 73 genes selected by machine learning models were up-regulated in response to AM (Z-value difference > 0.5). Feature weighting models also documented that this signature is independent from study (batch) effect. The AM inoculation signature obtained was able to differentiate efficiently between AM inoculated and non-inoculated samples. The AP2 domain class transcription factor, GRAS family transcription factors, and cyclin-dependent kinase were among the highly expressed meta-genes identified in the signature. We found high correspondence between the AM colonization signature obtained in this study and independent RNA-seq experiments on AM colonization, validating the repeatability of the colonization signature. Promoter analysis of upregulated genes in the transcriptomic signature led to the key regulators of AM colonization, including the essential transcription factors for endosymbiosis establishment and development such as NF-YA factors. The approach developed in this study offers three distinct novel features: (I) it improves direct merging meta-analysis by integrating supervised machine learning models and normalization steps to reduce study-specific batch effects; (II) seven attribute weighting models assessed the suitability of each gene for the transcriptomic signature which contributes to robustness of the signature (III) the approach is justifiable, easy to apply, and useful in practice. Our integrative framework of meta-analysis, promoter analysis, and machine learning provides a foundation to reveal the transcriptomic signature and regulatory circuits governing Arbuscular mycorrhizal symbiosis and is transferable to the other biological settings.},
}
@article {pmid30479610,
year = {2018},
author = {Bauça, JM},
title = {Reflections on the Mentor-Mentee Relationship: A Symbiosis.},
journal = {EJIFCC},
volume = {29},
number = {3},
pages = {230-233},
pmid = {30479610},
issn = {1650-3414},
}
@article {pmid30478939,
year = {2018},
author = {Seró, R and Núñez, N and Núñez, O and Camprubí, A and Grases, JM and Saurina, J and Moyano, E and Calvet, C},
title = {Modified distribution in the polyphenolic profile of rosemary leaves induced by plant inoculation with an arbuscular mycorrhizal fungus.},
journal = {Journal of the science of food and agriculture},
volume = {},
number = {},
pages = {},
doi = {10.1002/jsfa.9510},
pmid = {30478939},
issn = {1097-0010},
abstract = {BACKGROUND: Rosemary forms an arbuscular mycorrhizal (AM) symbiosis with a group of soilborne fungi belonging to the phylum Glomeromycota, which can modify the plant metabolome responsible for the antioxidant capacity and other health beneficial properties of Rosemary.<br><br>RESULTS: The effect of inoculating rosemary plants with an AM fungus on their growth via their polyphenolic fingerprinting was evaluated after analyzing leaf extracts from non-inoculated and inoculated rosemary plants by ultra-high performance liquid chromatography-high resolution mass spectrometry. . Plant growth parameters indicated that mycorrhizal inoculation significantly increased plant height and biomass. Chemical modifications in the plant polyphenolic profile distribution were found after a principal components analysis (PCA) loading plots study. Four compounds hosting strong antioxidant properties: ferulic acid, asiatic acid, carnosol, and vanillin were related to mycorrhizal rosemary plants while caffeic and chlorogenic acids had a higher influence in non-mycorrhizal plants.<br><br>CONCLUSION: Mycorrhization was found to stimulate growth in order to obtain a higher biomass of plant leaves in short time and avoiding chemical fertilization, while analytical results demonstrate that there is an alteration in the distribution of polyphenols in plants colonized by the symbiotic fungus, which can be related to an improvement in nutritional properties with future industrial significance. This article is protected by copyright. All rights reserved.},
}
@article {pmid30477837,
year = {2018},
author = {Anheyer, D and Kern, C and Dobos, G and Cramer, H},
title = {&quot;I think you can achieve quite a lot if all of the staff stands behind it&quot;-A qualitative study about the experience, knowledge and application of complementary therapies and integrative medicine in pediatrics.},
journal = {Complementary therapies in medicine},
volume = {41},
number = {},
pages = {186-191},
doi = {10.1016/j.ctim.2018.09.025},
pmid = {30477837},
issn = {1873-6963},
abstract = {BACKGROUND: In the United States there is an increasing use of complementary and alternative medicine (CAM) as well as integrative medicine (IM) in pediatrics. This study investigates the extent of knowledge and practical application of and attitudes towards the use and integration of CAM/IM therapies in two German pediatric clinics.<br><br>METHODS: A semi-standardized qualitative interview study was conducted in a rural children's hospital in Bavaria and in a children's clinic in the metropolitan area of Ruhr. Sixteen employees (7 nurses, 9 medical doctors, 68.8% female), who had volunteered through a local contact, were questioned during their shift on CAM/IM therapies. The data collected were analyzed with MAXQDA 12 using a qualitative technique for content analysis (by Mayring).<br><br>RESULTS: On average all respondents had little to superficial knowledge about the possibilities or evidence base of the therapies concerned, but did believe that CAM/IM could be an enhancement. In addition, many took interest in learning more about CAM/IM medical options. Nurses desired more practical and theoretical knowledge; while medical doctors focused on standardization and evidence base. All of them agreed that self-care strategies could enhance parental independence when treating symptoms of minor illnesses. They further agreed, that a symbiosis of conventional medicine and CAM/IM has great potential for patients and employees. It was stated that training of staff would be indispensable in order to implement standardized procedures.<br><br>CONCLUSIONS: There is great potential and interest in CAM/IM among pediatric care employees. Regardless of the challenges, this investigation did find that implementing CAM/IM might be a promising extension to the daily care routine.},
}
@article {pmid30477264,
year = {2018},
author = {Almendras, K and García, J and Carú, M and Orlando, J},
title = {Nitrogen-Fixing Bacteria Associated with Peltigera Cyanolichens and Cladonia Chlorolichens.},
journal = {Molecules (Basel, Switzerland)},
volume = {23},
number = {12},
pages = {},
doi = {10.3390/molecules23123077},
pmid = {30477264},
issn = {1420-3049},
support = {11100381 and 1181510//Fondo Nacional de Desarrollo Científico y Tecnológico/ ; },
abstract = {Lichens have been extensively studied and described; however, recent evidence suggests that members of the bacterial community associated with them could contribute new functions to the symbiotic interaction. In this work, we compare the nitrogen-fixing guild associated with bipartite terricolous lichens with different types of photobiont: Peltigera cyanolichens and Cladonia chlorolichens. Since cyanobacteria contribute nitrogen to the symbiosis, we propose that chlorolichens have more diverse bacteria with the ability to fix nitrogen compared to cyanolichens. In addition, since part of these bacteria could be recruited from the substrate where lichens grow, we propose that thalli and substrates share some bacteria in common. The structure of the nitrogen-fixing guild in the lichen and substrate bacterial communities of both lichens was determined by terminal restriction fragment length polymorphism (TRFLP) of the nifH gene. Multivariate analyses showed that the nitrogen-fixing bacteria associated with both types of lichen were distinguishable from those present in their substrates. Likewise, the structure of the nitrogen-fixing bacteria present in the cyanolichens was different from that of chlorolichens. Finally, the diversity of this bacterial guild calculated using the Shannon index confirms the hypothesis that chlorolichens have a higher diversity of nitrogen-fixing bacteria than cyanolichens.},
}
@article {pmid30476329,
year = {2018},
author = {Valdés-López, O and Jayaraman, D and Maeda, J and Delaux, PM and Venkateshwaran, M and Isidra-Arellano, MC and Del Rocío Reyero-Saavedra, M and Del Socorro Sánchez-Correa, M and Verastegui-Vidal, MA and Delgado-Buenrostro, N and Van Ness, L and Mysore, KS and Wen, J and Sussman, MR and Ané, JM},
title = {A Novel Positive Regulator of the Early Stages of the Root Nodule Symbiosis Identified by Phosphoproteomics.},
journal = {Plant &amp; cell physiology},
volume = {},
number = {},
pages = {},
doi = {10.1093/pcp/pcy228},
pmid = {30476329},
issn = {1471-9053},
abstract = {Signals and signaling pathways underlying the symbiosis between legumes and rhizobia have been studied extensively over the past decades. In a previous phosphoproteomic study on the Medicago truncatula - Sinorhizobium meliloti symbiosis, we identified plant proteins that are differentially phosphorylated upon the perception of rhizobial signals, called Nod factors. In this study, we provide experimental evidence that one of these proteins, Early Phosphorylated Protein 1 (EPP1), is required for the initiation of this symbiosis. Upon inoculation with rhizobia, MtEPP1 expression was induced in curled root hairs. Down-regulation of MtEPP1 in M. truncatula roots almost abolished calcium spiking, reduced the expression of essential symbiosis-related genes (MtNIN, MtNF-YB1, MtERN1, and MtENOD40), and strongly decreased nodule development. Phylogenetic analyses revealed that orthologs of MtEPP1 are present in legumes and specifically in plant species able to host arbuscular mycorrhizal fungi, suggesting a possible role in this association too. Short chitin oligomers induced the phosphorylation of MtEPP1 like Nod factors. However, the down-regulation of MtEPP1 affected the colonization of M. truncatula roots by arbuscular mycorrhizal fungi only moderately. Altogether, these findings indicate that MtEPP1 is essential for the establishment of the legume-rhizobia symbiosis but might plays a limited role in the arbuscular mycorrhizal symbiosis.},
}
@article {pmid30476071,
year = {2018},
author = {Alonso, D and Mancini, MV and Damiani, C and Cappelli, A and Ricci, I and Niz Alvarez, MV and Bandi, C and Ribolla, P and Favia, G},
title = {Genome reduction in the mosquito symbiont Asaia.},
journal = {Genome biology and evolution},
volume = {},
number = {},
pages = {},
doi = {10.1093/gbe/evy255},
pmid = {30476071},
issn = {1759-6653},
abstract = {Symbiosis is now recognized as a driving force in evolution, a role that finds its ultimate expression in the variety of associations bonding insects with microbial symbionts. These associations have contributed to the evolutionary success of insects, with the hosts acquiring the capacity to exploit novel ecological niches, and the symbionts passing from facultative associations to obligate, mutualistic symbioses. In bacterial symbiont of insects, the transition from the free-living life style to mutualistic symbiosis often resulted in a reduction in the genome size, with the generation of the smallest bacterial genomes thus far described. Here we show that the process of genome reduction is still occurring in Asaia, a group of bacterial symbionts associated with a variety of insects. Indeed, comparative genomics of Asaia isolated from different mosquito species revealed a substantial genome size and gene content reduction in Asaia from Anopheles darlingi, a South-American malaria vector. We thus propose Asaia as a novel model to study genome reduction dynamics, within a single bacterial taxon, evolving in a common biological niche.},
}
@article {pmid30471496,
year = {2018},
author = {Yang, T and Cheng, H and Wang, H and Drews, M and Li, S and Huang, W and Zhou, H and Chen, CM and Diao, X},
title = {Comparative study of polycyclic aromatic hydrocarbons (PAHs) and heavy metals (HMs) in corals, surrounding sediments and surface water at the Dazhou Island, China.},
journal = {Chemosphere},
volume = {218},
number = {},
pages = {157-168},
doi = {10.1016/j.chemosphere.2018.11.063},
pmid = {30471496},
issn = {1879-1298},
abstract = {This study investigated polycyclic aromatic hydrocarbons (PAHs) content in corals (Acropora sp.), surficial sediments, and surface seawater, and heavy metals (HMs) contents in corals and sediments from Dazhou Island, Hainan, China. Concentrations of PAHs in seawater and sediment seasonally ranged from 191.5 ng L-1 to 587.7 ng L-1, and from 37.9 ng g-1 to 233 ng g-1, while levels in corals were higher (185.2-545.0 ng g-1) compared to those found in sediments, demonstrating bioaccumulation of PAHs by corals. A similar seasonally variation of PAHs was observed in water/sediments and corals, and the proportions of low molecular weight PAHs (LPAHs) in seawater and corals were higher. Pyrolytic and petrogenic contaminations were identified to be the main sources of PAHs. Lower HMs concentrations were detected in corals (9.8-39.4 μg g-1) than in sediments (65.0-83.3 μg g-1), but HMs bioaccumulation still occurs in corals. Higher concentrations of HMs in sediment and corals were detected in March and December, especially Mn and Zn. Application of an enrichment factor showed that Cu in corals was delivered from non-crustal materials, and anthropogenic inputs were possibly the main sources. According to Biota Sediment Accumulation Factor, corals could strongly bioaccumulate LPAHs and Cd, and PAHs at a higher (p < 0.05) rate than HMs. There was a lack of correlation between the accumulation of PAHs and HMs in corals based on the cluster analysis. Dual hierarchical clustering analysis result revealed that feeding, instead of symbiosis, might be the main process responsible for the bioaccumulation of PAHs and HMs.},
}
@article {pmid30470196,
year = {2018},
author = {Doudoumis, V and Augustinos, A and Saridaki, A and Parker, A and Abd-Alla, AMM and Bourtzis, K and Tsiamis, G},
title = {Different laboratory populations similar bacterial profile? The case of Glossina palpalis gambiensis.},
journal = {BMC microbiology},
volume = {18},
number = {Suppl 1},
pages = {148},
doi = {10.1186/s12866-018-1290-9},
pmid = {30470196},
issn = {1471-2180},
abstract = {BACKGROUND: Microbiota plays an important role in the biology, ecology and evolution of insects including tsetse flies. The bacterial profile of 3 Glossina palpalis gambiensis laboratory colonies was examined using 16S rRNA gene amplicon sequencing to evaluate the dynamics of the bacterial diversity within and between each G. p. gambiensis colony.<br><br>RESULTS: The three G. p. gambiensis laboratory colonies displayed similar bacterial diversity indices and OTU distribution. Larval guts displayed a higher diversity when compared with the gastrointestinal tract of adults while no statistically significant differences were observed between testes and ovaries. Wigglesworthia and Sodalis were the most dominant taxa. In more detail, the gastrointestinal tract of adults was more enriched by Wigglesworthia while Sodalis were prominent in gonads. Interestingly, in larval guts a balanced co-existence between Wigglesworthia and Sodalis was observed. Sequences assigned to Wolbachia, Propionibacterium, and Providencia were also detected but to a much lesser degree. Clustering analysis indicated that the bacterial profile in G. p. gambiensis exhibits tissue tropism, hence distinguishing the gut bacterial profile from that present in reproductive organs.<br><br>CONCLUSIONS: Our results indicated that age, gender and the origin of the laboratory colonies did not significantly influence the formation of the bacterial profile, once these populations were kept under the same rearing conditions. Within the laboratory populations a tissue tropism was observed between the gut and gonadal bacterial profile.},
}
@article {pmid30470190,
year = {2018},
author = {Augustinos, AA and Meki, IK and Demirbas-Uzel, G and Ouédraogo, GMS and Saridaki, A and Tsiamis, G and Parker, AG and Abd-Alla, AMM and Bourtzis, K},
title = {Nuclear and Wolbachia-based multimarker approach for the rapid and accurate identification of tsetse species.},
journal = {BMC microbiology},
volume = {18},
number = {Suppl 1},
pages = {147},
doi = {10.1186/s12866-018-1295-4},
pmid = {30470190},
issn = {1471-2180},
abstract = {BACKGROUND: Tsetse flies (Diptera: Glossinidae) are solely responsible for the transmission of African trypanosomes, causative agents of sleeping sickness in humans and nagana in livestock. Due to the lack of efficient vaccines and the emergence of drug resistance, vector control approaches such as the sterile insect technique (SIT), remain the most effective way to control disease. SIT is a species-specific approach and therefore requires accurate identification of natural pest populations at the species level. However, the presence of morphologically similar species (species complexes and sub-species) in tsetse flies challenges the successful implementation of SIT-based population control.<br><br>RESULTS: In this study, we evaluate different molecular tools that can be applied for the delimitation of different Glossina species using tsetse samples derived from laboratory colonies, natural populations and museum specimens. The use of mitochondrial markers, nuclear markers (including internal transcribed spacer 1 (ITS1) and different microsatellites), and bacterial symbiotic markers (Wolbachia infection status) in combination with relatively inexpensive techniques such as PCR, agarose gel electrophoresis, and to some extent sequencing provided a rapid, cost effective, and accurate identification of several tsetse species.<br><br>CONCLUSIONS: The effectiveness of SIT benefits from the fine resolution of species limits in nature. The present study supports the quick identification of large samples using simple and cost effective universalized protocols, which can be easily applied by countries/laboratories with limited resources and expertise.},
}
@article {pmid30470188,
year = {2018},
author = {Engl, T and Michalkova, V and Weiss, BL and Uzel, GD and Takac, P and Miller, WJ and Abd-Alla, AMM and Aksoy, S and Kaltenpoth, M},
title = {Effect of antibiotic treatment and gamma-irradiation on cuticular hydrocarbon profiles and mate choice in tsetse flies (Glossina m. morsitans).},
journal = {BMC microbiology},
volume = {18},
number = {Suppl 1},
pages = {145},
doi = {10.1186/s12866-018-1292-7},
pmid = {30470188},
issn = {1471-2180},
abstract = {BACKGROUND: Symbiotic microbes represent a driving force of evolutionary innovation by conferring novel ecological traits to their hosts. Many insects are associated with microbial symbionts that contribute to their host's nutrition, digestion, detoxification, reproduction, immune homeostasis, and defense. In addition, recent studies suggest a microbial involvement in chemical communication and mating behavior, which can ultimately impact reproductive isolation and, hence, speciation. Here we investigated whether a disruption of the microbiota through antibiotic treatment or irradiation affects cuticular hydrocarbon profiles, and possibly mate choice behavior in the tsetse fly, Glossina morsitans morsitans. Four independent experiments that differentially knock down the multiple bacterial symbionts of tsetse flies were conducted by subjecting tsetse flies to ampicillin, tetracycline, or gamma-irradiation and analyzing their cuticular hydrocarbon profiles in comparison to untreated controls by gas chromatography - mass spectrometry. In two of the antibiotic experiments, flies were mass-reared, while individual rearing was done for the third experiment to avoid possible chemical cross-contamination between individual flies.<br><br>RESULTS: All three antibiotic experiments yielded significant effects of antibiotic treatment (particularly tetracycline) on cuticular hydrocarbon profiles in both female and male G. m. morsitans, while irradiation itself had no effect on the CHC profiles. Importantly, tetracycline treatment reduced relative amounts of 15,19,23-trimethyl-heptatriacontane, a known compound of the female contact sex pheromone, in two of the three experiments, suggesting a possible implication of microbiota disturbance on mate choice decisions. Concordantly, both female and male flies preferred non-treated over tetracycline-treated flies in direct choice assays.<br><br>CONCLUSIONS: While we cannot exclude the possibility that antibiotic treatment had a directly detrimental effect on fly vigor as we are unable to recolonize antibiotic treated flies with individual symbiont taxa, our results are consistent with an effect of the microbiota, particularly the obligate nutritional endosymbiont Wigglesworthia, on CHC profiles and mate choice behavior. These findings highlight the importance of considering host-microbiota interactions when studying chemical communication and mate choice in insects.},
}
@article {pmid30470176,
year = {2018},
author = {Zaidman-Rémy, A and Vigneron, A and Weiss, BL and Heddi, A},
title = {What can a weevil teach a fly, and reciprocally? Interaction of host immune systems with endosymbionts in Glossina and Sitophilus.},
journal = {BMC microbiology},
volume = {18},
number = {Suppl 1},
pages = {150},
doi = {10.1186/s12866-018-1278-5},
pmid = {30470176},
issn = {1471-2180},
support = {R01 AI051584/AI/NIAID NIH HHS/United States ; },
abstract = {The tsetse fly (Glossina genus) is the main vector of African trypanosomes, which are protozoan parasites that cause human and animal African trypanosomiases in Sub-Saharan Africa. In the frame of the IAEA/FAO program 'Enhancing Vector Refractoriness to Trypanosome Infection', in addition to the tsetse, the cereal weevil Sitophilus has been introduced as a comparative system with regards to immune interactions with endosymbionts. The cereal weevil is an agricultural pest that destroys a significant proportion of cereal stocks worldwide. Tsetse flies are associated with three symbiotic bacteria, the multifunctional obligate Wigglesworthia glossinidia, the facultative commensal Sodalis glossinidius and the parasitic Wolbachia. Cereal weevils house an obligatory nutritional symbiosis with the bacterium Sodalis pierantonius, and occasionally Wolbachia. Studying insect host-symbiont interactions is highly relevant both for understanding the evolution of symbiosis and for envisioning novel pest control strategies. In both insects, the long co-evolution between host and endosymbiont has led to a stringent integration of the host-bacteria partnership. These associations were facilitated by the development of specialized host traits, including symbiont-housing cells called bacteriocytes and specific immune features that enable both tolerance and control of the bacteria. In this review, we compare the tsetse and weevil model systems and compile the latest research findings regarding their biological and ecological similarities, how the immune system controls endosymbiont load and location, and how host-symbiont interactions impact developmental features including cuticle synthesis and immune system maturation. We focus mainly on the interactions between the obligate symbionts and their host's immune systems, a central theme in both model systems. Finally, we highlight how parallel studies on cereal weevils and tsetse flies led to mutual discoveries and stimulated research on each model, creating a pivotal example of scientific improvement through comparison between relatively distant models.},
}
@article {pmid30467509,
year = {2018},
author = {Libault, M},
title = {Transcriptional Reprogramming of Legume Genomes: Perspective and Challenges Associated With Single-Cell and Single Cell-Type Approaches During Nodule Development.},
journal = {Frontiers in plant science},
volume = {9},
number = {},
pages = {1600},
doi = {10.3389/fpls.2018.01600},
pmid = {30467509},
issn = {1664-462X},
abstract = {Transcriptomic approaches revealed thousands of genes differentially or specifically expressed during nodulation, a biological process resulting from the symbiosis between leguminous plant roots and rhizobia, atmospheric nitrogen-fixing symbiotic bacteria. Ultimately, nodulation will lead to the development of a new root organ, the nodule. Through functional genomic studies, plant transcriptomes have been used by scientists to reveal plant genes potentially controlling nodulation. However, it is important to acknowledge that the physiology, transcriptomic programs, and biochemical properties of the plant cells involved in nodulation are continuously regulated. They also differ between the different cell-types composing the nodules. To generate a more accurate picture of the transcriptome, epigenome, proteome, and metabolome of the cells infected by rhizobia and cells composing the nodule, there is a need to implement plant single-cell and single cell-types strategies and methods. Accessing such information would allow a better understanding of the infection of plant cells by rhizobia and will help understanding the complex interactions existing between rhizobia and the plant cells. In this mini-review, we are reporting the current knowledge on legume nodulation gained by plant scientists at the level of single cell-types, and provide perspectives on single cell/single cell-type approaches when applied to legume nodulation.},
}
@article {pmid30467310,
year = {2018},
author = {Pollock, FJ and McMinds, R and Smith, S and Bourne, DG and Willis, BL and Medina, M and Thurber, RV and Zaneveld, JR},
title = {Coral-associated bacteria demonstrate phylosymbiosis and cophylogeny.},
journal = {Nature communications},
volume = {9},
number = {1},
pages = {4921},
doi = {10.1038/s41467-018-07275-x},
pmid = {30467310},
issn = {2041-1723},
abstract = {Scleractinian corals' microbial symbionts influence host health, yet how coral microbiomes assembled over evolution is not well understood. We survey bacterial and archaeal communities in phylogenetically diverse Australian corals representing more than 425 million years of diversification. We show that coral microbiomes are anatomically compartmentalized in both modern microbial ecology and evolutionary assembly. Coral mucus, tissue, and skeleton microbiomes differ in microbial community composition, richness, and response to host vs. environmental drivers. We also find evidence of coral-microbe phylosymbiosis, in which coral microbiome composition and richness reflect coral phylogeny. Surprisingly, the coral skeleton represents the most biodiverse coral microbiome, and also shows the strongest evidence of phylosymbiosis. Interactions between bacterial and coral phylogeny significantly influence the abundance of four groups of bacteria-including Endozoicomonas-like bacteria, which divide into host-generalist and host-specific subclades. Together these results trace microbial symbiosis across anatomy during the evolution of a basal animal lineage.},
}
@article {pmid30466096,
year = {2018},
author = {Antonopoulos, CN and Liapis, CD},
title = {Aneurysms and Diabetes Mellitus: A Strange Symbiosis?.},
journal = {Cardiology},
volume = {141},
number = {2},
pages = {123-124},
doi = {10.1159/000490925},
pmid = {30466096},
issn = {1421-9751},
}
@article {pmid30465068,
year = {2018},
author = {Hubert, J and Nesvorna, M and Kopecky, J and Erban, T and Klimov, P},
title = {Population and Culture Age Influence the Microbiome Profiles of House Dust Mites.},
journal = {Microbial ecology},
volume = {},
number = {},
pages = {},
doi = {10.1007/s00248-018-1294-x},
pmid = {30465068},
issn = {1432-184X},
support = {17-12068S//Grantová Agentura České Republiky/ ; (No. 6.1933.2014/K Project Code 1933//Ministry of Education and Science of the Russian Federation/ ; No. 15-04-0s5185-a//the Russian Foundation for Basic Research/ ; },
abstract = {Interactions with microorganisms might enable house dust mites (HDMs) to derive nutrients from difficult-to-digest structural proteins and to flourish in human houses. We tested this hypothesis by investigating the effects of changes in the mite culture growth and population of two HDM species on HDM microbiome composition and fitness. Growing cultures of laboratory and industrial allergen-producing populations of Dermatophagoides farinae (DFL and DFT, respectively) and Dermatophagoides pteronyssinus (DPL and DPT, respectively) were sampled at four time points. The symbiotic microorganisms of the mites were characterized by DNA barcode sequencing and quantified by qPCR using universal/specific primers. The population growth of mites and nutrient contents of mite bodies were measured and correlated with the changes in bacteria in the HDM microbiome. The results showed that both the population and culture age significantly influenced the microbiome profiles. Cardinium formed 93% and 32% of the total sequences of the DFL and DFT bacterial microbiomes, respectively, but this bacterial species was less abundant in the DPL and DPT microbiomes. Staphylococcus abundance was positively correlated with increased glycogen contents in the bodies of mites, and increased abundances of Aspergillus, Candida, and Kocuria were correlated with increased lipid contents in the bodies of mites. The xerophilic fungus Wallemia accounted for 39% of the fungal sequences in the DPL microbiome, but its abundance was low in the DPT, DFL, and DFT microbiomes. With respect to the mite culture age, we made three important observations: the mite population growth from young cultures was 5-8-fold higher than that from old cultures; specimens from old cultures had greater abundances of fungi and bacteria in their bodies; and yeasts predominated in the gut contents of specimens from young cultures, whereas filamentous mycelium prevailed in specimens from old cultures. Our results are consistent with the hypothesis that mites derive nutrients through associations with microorganisms.},
}
@article {pmid30463949,
year = {2018},
author = {Mao, M and Yang, X and Bennett, GM},
title = {Evolution of host support for two ancient bacterial symbionts with differentially degraded genomes in a leafhopper host.},
journal = {Proceedings of the National Academy of Sciences of the United States of America},
volume = {},
number = {},
pages = {},
doi = {10.1073/pnas.1811932115},
pmid = {30463949},
issn = {1091-6490},
abstract = {Plant sap-feeding insects (Hemiptera) rely on bacterial symbionts for nutrition absent in their diets. These bacteria experience extreme genome reduction and require genetic resources from their hosts, particularly for basic cellular processes other than nutrition synthesis. The host-derived mechanisms that complete these processes have remained poorly understood. It is also unclear how hosts meet the distinct needs of multiple bacterial partners with differentially degraded genomes. To address these questions, we investigated the cell-specific gene-expression patterns in the symbiotic organs of the aster leafhopper (ALF), Macrosteles quadrilineatus (Cicadellidae). ALF harbors two intracellular symbionts that have two of the smallest known bacterial genomes: Nasuia (112 kb) and Sulcia (190 kb). Symbionts are segregated into distinct host cell types (bacteriocytes) and vary widely in their basic cellular capabilities. ALF differentially expresses thousands of genes between the bacteriocyte types to meet the functional needs of each symbiont, including the provisioning of metabolites and support of cellular processes. For example, the host highly expresses genes in the bacteriocytes that likely complement gene losses in nucleic acid synthesis, DNA repair mechanisms, transcription, and translation. Such genes are required to function in the bacterial cytosol. Many host genes comprising these support mechanisms are derived from the evolution of novel functional traits via horizontally transferred genes, reassigned mitochondrial support genes, and gene duplications with bacteriocyte-specific expression. Comparison across other hemipteran lineages reveals that hosts generally support the incomplete symbiont cellular processes, but the origins of these support mechanisms are generally specific to the host-symbiont system.},
}
@article {pmid30463525,
year = {2018},
author = {Toju, H and Sato, H and Yamamoto, S and Tanabe, AS},
title = {Structural diversity across arbuscular mycorrhizal, ectomycorrhizal, and endophytic plant-fungus networks.},
journal = {BMC plant biology},
volume = {18},
number = {1},
pages = {292},
doi = {10.1186/s12870-018-1500-5},
pmid = {30463525},
issn = {1471-2229},
support = {26711026//Japan Society for the Promotion of Science/ ; JPMJPR16Q6//Precursory Research for Embryonic Science and Technology/ ; GS014//Cabinet Office, Government of Japan/ ; },
abstract = {BACKGROUND: Below-ground linkage between plant and fungal communities is one of the major drivers of terrestrial ecosystem dynamics. However, we still have limited knowledge of how such plant-fungus associations vary in their community-scale properties depending on fungal functional groups and geographic locations.<br><br>METHODS: By compiling a high-throughput sequencing dataset of root-associated fungi in eight forests along the Japanese Archipelago, we performed a comparative analysis of arbuscular mycorrhizal, ectomycorrhizal, and saprotrophic/endophytic associations across a latitudinal gradient from cool-temperate to subtropical regions.<br><br>RESULTS: In most of the plant-fungus networks analyzed, host-symbiont associations were significantly specialized but lacked &quot;nested&quot; architecture, which has been commonly reported in plant-pollinator and plant-seed disperser networks. In particular, the entire networks involving all functional groups of plants and fungi and partial networks consisting of ectomycorrhizal plant and fungal species/taxa displayed &quot;anti-nested&quot; architecture (i.e., negative nestedness scores) in many of the forests examined. Our data also suggested that geographic factors affected the organization of plant-fungus network structure. For example, the southernmost subtropical site analyzed in this study displayed lower network-level specificity of host-symbiont associations and higher (but still low) nestedness than northern localities.<br><br>CONCLUSIONS: Our comparative analyses suggest that arbuscular mycorrhizal, ectomycorrhizal, and saprotrophic/endophytic plant-fungus associations often lack nested network architecture, while those associations can vary, to some extent, in their community-scale properties along a latitudinal gradient. Overall, this study provides a basis for future studies that will examine how different types of plant-fungus associations collectively structure terrestrial ecosystems.},
}
@article {pmid30462254,
year = {2018},
author = {Hernández-López, A and Díaz, M and Rodríguez-López, J and Guillén, G and Sánchez, F and Díaz-Camino, C},
title = {The overexpression of Bax inhibitor-1 in common bean roots highlights its dual role in the legume-rhizobia symbiosis.},
journal = {Journal of experimental botany},
volume = {},
number = {},
pages = {},
doi = {10.1093/jxb/ery417},
pmid = {30462254},
issn = {1460-2431},
abstract = {Bax-inhibitor 1 (BI-1) is a cell death suppressor conserved in all eukaryotes that modulates cell death in response to abiotic stress and pathogen attack in plants. Thus far nothing is known about its role in the establishment of symbiotic interactions. Here, we demonstrate the functional relevance of an Arabidopsisthaliana BI-1 homolog (PvBI-1a) to symbiosis between the common bean (Phaseolus vulgaris) and Rhizobium tropici. We show that the PvBI-1a expression changes observed during early symbiosis resemble those of some defence-response related proteins. By using gain- and loss-of-function approaches, we demonstrate that the overexpression of PvBI-1a in the roots of common bean increases the number of rhizobial infection events (and therefore the final number of nodules per root), but induces the premature death of nodule cells, thus affecting their nitrogen fixation efficiency. Nodule morphological alterations are known to be associated with changes in the expression of genes tied to defence, autophagy, and vesicular trafficking. Results obtained in the present work suggest that BI-1 has a dual role in the regulation of programmed cell death during symbiosis, thus extending our understanding about its critical function in the modulation of host immunity while responding to by beneficial microbes.},
}
@article {pmid30460828,
year = {2018},
author = {Song, YY and Xia, M and Lin, YB and Lin, XH and Ding, CH and Wang, J and Hu, L and Zeng, RS},
title = {[Colonization with arbuscular mycorrhizal fungus Funneliformis mosseae enhanced the responses of tomato plants to mechanical wounding].},
journal = {Ying yong sheng tai xue bao = The journal of applied ecology},
volume = {29},
number = {11},
pages = {3811-3818},
doi = {10.13287/j.1001-9332.201811.035},
pmid = {30460828},
issn = {1001-9332},
abstract = {Insect herbivore feeding causes mechanical damage to plants, which can activate plant defense responses. Whether symbiosis with beneficial microorganisms can enhance the responses of plants to mechanical damage is of importance for plant anti-herbivore resistance. In this study, defense responses of tomato (Lycopersicon esculentum) plants to mechanical wounding was investigated after the tomato roots being infected by arbuscular mycorrhizal fungus (AMF) Funneliformis mosseae. The results showed that in response to leaf mechanical wounding, the activities of phenylalanine ammonia-lyase (PAL), superoxide dismutase (SOD), peroxidase (POD), polyphenol oxidase (PPO) and catalase (CAT) in the leaves of tomato pre-inoculated with AMF (FD), as well as transcript levels of genes encoding phenylalanine ammonia lyase (PAL) and β-1,3-glucanase (PR2) in the leaves and roots were significantly higher in relative to sole mechanical wounding (D), sole mycorrhizal inoculation (F), and control without mechanical wounding and mycorrhizal inoculation (CK). Although the activities of protective enzyme and transcript levels of the two defense-related genes were induced in the plants of sole mechanical wounding (D) and sole mycorrhizal inoculation (F), the induction was faster and stronger in the plants with leaf mechanical wounding and mycorrhizal pre-inoculation (FD). Our findings indicated that arbuscular mycorrhizal colonization could prime quicker and stronger defense responses of tomato plants to mechanical damage.},
}
@article {pmid30460206,
year = {2018},
author = {Arora, G and Chaudhary, D and Kidwai, S and Sharma, D and Singh, R},
title = {CitE Enzymes Are Essential for Mycobacterium tuberculosis to Establish Infection in Macrophages and Guinea Pigs.},
journal = {Frontiers in cellular and infection microbiology},
volume = {8},
number = {},
pages = {385},
doi = {10.3389/fcimb.2018.00385},
pmid = {30460206},
issn = {2235-2988},
abstract = {Bacterial citrate lyase activity has been demonstrated in various eukaryotes, bacteria and archaea, underscoring their importance in energy metabolism of the cell. While the bacterial citrate lyase comprises of three different subunits, M. tuberculosis genome lacks CitD and CitF subunits of citrate lyase complex but encodes for 2 homologs of CitE subunits, Rv2498c and Rv3075c. Using temperature sensitive mycobacteriophages, we were able to generate both single and double citE mutant strains of M. tuberculosis. The survival experiments revealed increased susceptibility of the double mutant strain to oxidative stress in comparison to the parental strain. Also, simultaneous deletion of both citE1 and citE2 in M. tuberculosis genome resulted in impairment of intracellular replication in macrophages. The double mutant strain displayed reduced growth in lungs and spleens of guinea pigs. This is the first study demonstrating that M. tuberculosis critically requires CitE subunits of citrate lyase for pathogenesis. Taken together, these findings position these enzymes as potential targets for development of anti-tubercular small molecules.},
}
@article {pmid30459800,
year = {2018},
author = {Grosche, C and Genau, AC and Rensing, SA},
title = {Evolution of the Symbiosis-Specific GRAS Regulatory Network in Bryophytes.},
journal = {Frontiers in plant science},
volume = {9},
number = {},
pages = {1621},
doi = {10.3389/fpls.2018.01621},
pmid = {30459800},
issn = {1664-462X},
abstract = {Arbuscular mycorrhiza is one of the most common plant symbiotic interactions observed today. Due to their nearly ubiquitous occurrence and their beneficial impact on both partners it was suggested that this mutualistic interaction was crucial for plants to colonize the terrestrial habitat approximately 500 Ma ago. On the plant side the association is established via the common symbiotic pathway (CSP). This pathway allows the recognition of the fungal symbiotic partner, subsequent signaling to the nucleus, and initiation of the symbiotic program with respect to specific gene expression and cellular re-organization. The downstream part of the CSP is a regulatory network that coordinates the transcription of genes necessary to establish the symbiosis, comprising multiple GRAS transcription factors (TFs). These regulate their own expression as an intricate transcriptional network. Deduced from non-host genome data the loss of genes encoding CSP components coincides with the loss of the interaction itself. Here, we analyzed bryophyte species with special emphasis on the moss Physcomitrella patens, supposed to be a non-host, for the composition of the GRAS regulatory network components. We show lineage specific losses and expansions of several of these factors in bryophytes, potentially coinciding with the proposed host/non-host status of the lineages. We evaluate losses and expansions and infer clade-specific evolution of GRAS TFs.},
}
@article {pmid30459731,
year = {2018},
author = {Chun, SC and Paramasivan, M and Chandrasekaran, M},
title = {Proline Accumulation Influenced by Osmotic Stress in Arbuscular Mycorrhizal Symbiotic Plants.},
journal = {Frontiers in microbiology},
volume = {9},
number = {},
pages = {2525},
doi = {10.3389/fmicb.2018.02525},
pmid = {30459731},
issn = {1664-302X},
abstract = {Salinity and drought are the major osmotic stress limitations that affect plant growth and crop yield in agriculture worldwide. The alternative response mediated by plants in response to salinity and drought are principally proline accumulation which regulates stress combat strategies owing to sustainable production in the realm of agricultural production even under severe stress. Symbiotic and soil associated arbuscular mycorrhizal fungi (AMF) are regarded as efficient biofertilizers in several crops under these stresses. Summarily AMF is renowned for effective scavengers of free radicals in soil thereby increasing soil parameters optimal for plant growth. AMF contribute to augment host plant tolerance to stress specifically salinity and drought. Mycorrhizal colonization positively regulates root uptake of available nutrients and enhance growth even when bestowed by water constraints which has contributory roles due to proline accumulation providing several intriguing researches on AMF symbiosis pertaining to plant productivity and yield. Mycorrhizal plants and their non-mycorrhizal counterparts show varied expression pattern regarding proline amass. Hence, the precise role of proline with respect to stress tolerance and equivocal mechanisms involved in evasion of osmotic stress has not been extensively reviewed earlier. Further molecular forecasting in this arena is still an underexploited research field. This review comprehensively addresses the observable facts pertaining to proline accumulation upon AMF association and adherence relevant to stress tolerance and host plant efficiency and efficacy.},
}
@article {pmid30459726,
year = {2018},
author = {Brown, AMV and Wasala, SK and Howe, DK and Peetz, AB and Zasada, IA and Denver, DR},
title = {Comparative Genomics of Wolbachia-Cardinium Dual Endosymbiosis in a Plant-Parasitic Nematode.},
journal = {Frontiers in microbiology},
volume = {9},
number = {},
pages = {2482},
doi = {10.3389/fmicb.2018.02482},
pmid = {30459726},
issn = {1664-302X},
abstract = {Wolbachia and Cardinium are among the most important and widespread of all endosymbionts, occurring in nematodes and more than half of insect and arachnid species, sometimes as coinfections. These symbionts are of significant interest as potential biocontrol agents due to their abilities to cause major effects on host biology and reproduction through cytoplasmic incompatibility, sex ratio distortion, or obligate mutualism. The ecological and metabolic effects of coinfections are not well understood. This study examined a Wolbachia-Cardinium coinfection in the plant-parasitic nematode (PPN), Pratylenchus penetrans, producing the first detailed study of such a coinfection using fluorescence in situ hybridization (FISH), polymerase chain reaction (PCR), and comparative genomic analysis. Results from FISH and single-nematode PCR showed 123/127 individuals in a focal population carried Cardinium (denoted strain cPpe), and 48% were coinfected with Wolbachia strain wPpe. Both endosymbionts showed dispersed tissue distribution with highest densities in the anterior intestinal walls and gonads. Phylogenomic analyses confirmed an early place of cPpe and long distance from a sister strain in another PPN, Heterodera glycines, supporting a long history of both Cardinium and Wolbachia in PPNs. The genome of cPpe was 1.36 Mbp with 35.8% GC content, 1,131 predicted genes, 41% having no known function, and missing biotin and lipoate synthetic capacity and a plasmid present in other strains, despite having a slightly larger genome compared to other sequenced Cardinium. The larger genome revealed expansions of gene families likely involved in host-cellular interactions. More than 2% of the genes of cPpe and wPpe were identified as candidate horizontally transferred genes, with some of these from eukaryotes, including nematodes. A model of the possible Wolbachia-Cardinium interaction is proposed with possible complementation in function for pathways such as methionine and fatty acid biosynthesis and biotin transport.},
}
@article {pmid30459295,
year = {2018},
author = {Rubio, AO and Kupferberg, SJ and Vargas García, V and Ttito, A and Shepack, A and Catenazzi, A},
title = {Widespread occurrence of the antifungal cutaneous bacterium Janthinobacterium lividum on Andean water frogs threatened by fungal disease.},
journal = {Diseases of aquatic organisms},
volume = {131},
number = {3},
pages = {233-238},
doi = {10.3354/dao03298},
pmid = {30459295},
issn = {0177-5103},
abstract = {Amphibian diversity has declined due to the infectious disease chytridiomycosis, caused by the fungal pathogen Batrachochytrium dendrobatidis (Bd). Coexistence between amphibian hosts and this pathogen in some locations is attributed to the presence of the cutaneous bacterium Janthinobacterium lividum (Jliv). This microbe inhibits the growth of Bd on the host, reduces morbidity, and improves survival. Andean water frogs in the genus Telmatobius seem to be particularly vulnerable to the disease yet populations of T. intermedius and T. marmoratus persist in southern and central Peru. We investigated the presence of Jliv on these 2 frog species and assessed the relationship of Jliv presence with prevalence and intensity of Bd infection. By sampling 125 frogs from 7 streams (3323-3950 m a.s.l.) and 27 from a city market, we found spatial variation in the mutualism among populations (range 0-40% proportion of Jliv-positives). Overall, 57% of frogs were infected with Bd, 12.5% of frogs hosted both Jliv and Bd, while 7.2% hosted just Jliv. We found that the probability of an individual being infected with Bd was independent of the presence of Jliv; however, we did detect a protective effect of Jliv with respect to intensity of infection. The extent of Jliv distribution in the high Andes stands in stark contrast to the rarity of Jliv on frogs in lower elevation cloud forest biomes.},
}
@article {pmid30458424,
year = {2018},
author = {Salducci, MD and Folzer, H and Issartel, J and Rabier, J and Masotti, V and Prudent, P and Affre, L and Hardion, L and Tatoni, T and Laffont-Schwob, I},
title = {How can a rare protected plant cope with the metal and metalloid soil pollution resulting from past industrial activities? Phytometabolites, antioxidant activities and root symbiosis involved in the metal tolerance of Astragalus tragacantha.},
journal = {Chemosphere},
volume = {217},
number = {},
pages = {887-896},
doi = {10.1016/j.chemosphere.2018.11.078},
pmid = {30458424},
issn = {1879-1298},
abstract = {Astragalus tragacantha is a protected plant species in France that grows even in the trace metal and metalloid (TMM) polluted soils of the Calanques National Park (PNCal). Soils are mainly contaminated by lead, copper, zinc and arsenic. An ex situ experiment was conducted, firstly to determine the molecular responses and root traits involved in the TMM tolerance of this plant species by growing individuals in a soil from the surroundings of one of the brownfields of the PNCal, known as l'Escalette, where this plant species grows spontaneously. Secondly, in order to determine the plasticity of these responses, seeds were collected from three different populations, 1 at l'Escalette (polluted site), one from the Frioul archipelago (non-polluted, insular site) and one from La Seyne (non-polluted, littoral site). The results of this study confirmed the capacity of A. tragacantha to germinate and grow in TMM contaminated soils. Only moderate significant variations in chlorophyll and flavonol indices, proline content and antioxidant activities were detected between polluted and control soil conditions for all populations. The main driver for A. tragacantha TMM tolerance seemed to be its ability to be associated with root symbionts i.e. arbuscular mycorrhizal fungi and dark septate endophytes, corresponding to a nutrient-uptake strategy trait. This work provides support for the challenge of A. tragacantha conservation along the littoral of the PNCal, because increasing the number of A. tragacantha individuals would both increase vegetation cover of the polluted soils to reduce the pollution transfer and reinforce the populations of this species.},
}
@article {pmid30458368,
year = {2018},
author = {Tinkov, AA and Ajsuvakova, OP and Skalnaya, MG and Skalny, AV and Aschner, M and Suliburska, J and Aaseth, J},
title = {Organotins in obesity and associated metabolic disturbances.},
journal = {Journal of inorganic biochemistry},
volume = {191},
number = {},
pages = {49-59},
doi = {10.1016/j.jinorgbio.2018.11.002},
pmid = {30458368},
issn = {1873-3344},
abstract = {The objective of the present study was to review the mechanisms of organotin-induced adipogenesis, obesity, and associated metabolic disturbances. Peroxisome proliferator-activated receptor γ (PPARγ) and retinoid X receptor α (RXRα) activation is considered as the key mechanism of organotin-induced adipogenesis. Particularly, organotin exposure results in increased adipogenesis both in cell and animal models. Moreover, transgenerational inheritance of organotin-induced obese phenotype was demonstrated in vivo. At the same time, the existing data demonstrate that organotin compounds (OTCs) induces aberrant expression of PPARγ-targeted genes, resulting in altered of adipokine, glucose transporter, proinflammatory cytokines levels, and lipid and carbohydrate metabolism. The latter is generally characterized by hyperglycemia and insulin resistance. Other mechanisms involved in organotin-induced obesity may include estrogen receptor and corticosteroid signaling, altered DNA methylation, and gut dysfunction. In addition to cellular effects, organotin exposure may also affect neural circuits of appetite regulation, being characterized by neuropeptide Y (NPY) up-regulation in parallel with of pro-opiomelanocortin (POMC), Agouti-related protein (AgRP), and cocaine and amphetamine regulated transcript (CART) down-regulation in the arcuate nucleus. These changes result in increased orexigenic and reduced anorexigenic signaling, leading to increased food intake. The existing data demonstrate that organotins are potent adipogenic agents, however, no epidemiologic studies have been performed to reveal the association between organotin exposure and obesity and the existing indirect human data are contradictory.},
}
@article {pmid30458311,
year = {2018},
author = {Yu, J and Wang, M and Liu, B and Yue, X and Li, C},
title = {Gill symbionts of the cold-seep mussel Bathymodiolus platifrons: Composition, environmental dependency and immune control.},
journal = {Fish &amp; shellfish immunology},
volume = {86},
number = {},
pages = {246-252},
doi = {10.1016/j.fsi.2018.11.041},
pmid = {30458311},
issn = {1095-9947},
abstract = {Deep-sea Bathymodiolus mussels depend on the organic carbon supplied by symbionts inside their gills. In this study, optimized methods of quantitative real-time PCR and fluorescence in situ hybridization targeted to both mRNA and 16S rRNA were used to investigate the gill symbionts of the cold-seep mussel Bathymodiolus platifrons, including species composition, environmental dependency and immune control by the host. Our results showed that methanotrophs were the major symbiotic bacteria in the gills of B. platifrons, while thiotrophs were scarce. In the mussels freshly collected from the deep sea, methanotrophs were housed in bacteriocytes in a unique circular pattern, and a lysosome-related gene (VAMP) encoding a vesicle-associated membrane protein was expressed at a high level and presented exactly where the methanotrophs occurred. After the mussels were reared for three months in aquaria without methane supply, the abundance of methanotrophs decreased significantly and their circle-shaped distribution pattern disappeared; in addition, the expression of VAMP decreased significantly. These results suggest that the symbiosis between B. platifrons and methanotrophs is influenced by the environment and that the lysosomal system plays an important immune role in controlling the abundance of endosymbionts in host. This study provides a reliable method for investigating symbionts in deep-sea mussels and enriches the knowledge about symbionts in B. platifrons.},
}
@article {pmid30450723,
year = {2018},
author = {Prazeres, M and Renema, W},
title = {Evolutionary significance of the microbial assemblages of large benthic Foraminifera.},
journal = {Biological reviews of the Cambridge Philosophical Society},
volume = {},
number = {},
pages = {},
doi = {10.1111/brv.12482},
pmid = {30450723},
issn = {1469-185X},
support = {//Nederlandse Organisatie voor Wetenschappelijk Onderzoek (NWO)/ ; },
abstract = {Large benthic Foraminifera (LBF) are major carbonate producers on coral reefs, and are hosts to a diverse symbiotic microbial community. During warm episodes in the geological past, these reef-building organisms expanded their geographical ranges as subtropical and tropical belts moved into higher latitudes. During these range-expansion periods, LBF were the most prolific carbonate producers on reefs, dominating shallow carbonate platforms over reef-building corals. Even though the fossil and modern distributions of groups of species that harbour different types of symbionts are known, the nature, mechanisms, and factors that influence their occurrence remain elusive. Furthermore, the presence of a diverse and persistent bacterial community has only recently gained attention. We examined recent advances in molecular identification of prokaryotic (i.e. bacteria) and eukaryotic (i.e. microalgae) associates, and palaeoecology, and place the partnership with bacteria and algae in the context of climate change. In critically reviewing the available fossil and modern data on symbiosis, we reveal a crucial role of microalgae in the response of LBF to ocean warming, and their capacity to colonise a variety of habitats, across both latitudes and broad depth ranges. Symbiont identity is a key factor enabling LBF to expand their geographic ranges when the sea-surface temperature increases. Our analyses showed that over the past 66 million years (My), diatom-bearing species were dominant in reef environments. The modern record shows that these species display a stable, persistent eukaryotic assemblage across their geographic distribution range, and are less dependent on symbiotic photosynthesis for survival. By contrast, dinoflagellate and chlorophytic species, which show a provincial distribution, tend to have a more flexible eukaryotic community throughout their range. This group is more dependent on their symbionts, and flexibility in their symbiosis is likely to be the driving force behind their evolutionary history, as they form a monophyletic group originating from a rhodophyte-bearing ancestor. The study of bacterial assemblages, while still in its infancy, is a promising field of study. Bacterial communities are likely to be shaped by the local environment, although a core bacterial microbiome is found in species with global distributions. Cryptic speciation is also an important factor that must be taken into consideration. As global warming intensifies, genetic divergence in hosts in addition to the range of flexibility/specificity within host-symbiont associations will be important elements in the continued evolutionary success of LBF species in a wide range of environments. Based on fossil and modern data, we conclude that the microbiome, which includes both algal and bacterial partners, is a key factor influencing the evolution of LBF. As a result, the microbiome assists LBF in colonising a wide range of habitats, and allowed them to become the most important calcifiers on shallow platforms worldwide during periods of ocean warming in the geologic past. Since LBF are crucial ecosystem engineers and prolific carbonate producers, the microbiome is a critical component that will play a central role in the responses of LBF to a changing ocean, and ultimately in shaping the future of coral reefs.},
}
@article {pmid30450139,
year = {2018},
author = {Najafi, A and Moradinasab, M and Seyedabadi, M and Haghighi, MA and Nabipour, I},
title = {First Molecular Identification of Symbiotic Archaea in a Sponge Collected from the Persian Gulf, Iran.},
journal = {The open microbiology journal},
volume = {12},
number = {},
pages = {323-332},
doi = {10.2174/1874285801812010323},
pmid = {30450139},
issn = {1874-2858},
abstract = {Background: Marine sponges are associated with numerically vast and phylogenetically diverse microbial communities at different geographical locations. However, little is known about the archaeal diversity of sponges in the Persian Gulf. The present study was aimed to identify the symbiotic archaea with a sponge species gathered from the Persian Gulf, Iran.<br><br>Methods: Sponge sample was collected from a depth of 3 m offshore Bushehr, Persian Gulf, Iran. Metagenomic DNA was extracted using a hexadecyl trimethyl ammonium bromide (CTAB) method. The COI mtDNA marker was used for molecular taxonomy identification of sponge sample. Also, symbiotic archaea were identified using the culture-independent analysis of the 16S rRNA gene and PCR- cloning.<br><br>Results: In this study, analysis of multilocus DNA marker and morphological characteristics revealed that the sponge species belonged to Chondrilla australiensis isolate PG_BU4. PCR cloning and sequencing showed that all of the sequences of archaeal 16S rRNA gene libraries clustered into the uncultured archaeal group.<br><br>Conclusion: The present study is the first report of the presence of the genus of Chondrilla in the Persian Gulf. Traditional taxonomy methods, when used along with molecular techniques, could play a significant role in the accurate taxonomy of sponges. Also, the uncultured archaea may promise a potential source for bioactive compounds. Further functional studies are needed to explore the role of the sponge-associated uncultured archaea as a part of the marine symbiosis.},
}
@article {pmid30450084,
year = {2018},
author = {Gong, S and Chai, G and Xiao, Y and Xu, L and Yu, K and Li, J and Liu, F and Cheng, H and Zhang, F and Liao, B and Li, Z},
title = {Flexible Symbiotic Associations of Symbiodinium With Five Typical Coral Species in Tropical and Subtropical Reef Regions of the Northern South China Sea.},
journal = {Frontiers in microbiology},
volume = {9},
number = {},
pages = {2485},
doi = {10.3389/fmicb.2018.02485},
pmid = {30450084},
issn = {1664-302X},
abstract = {The coral symbiont Symbiodinium plays important roles in the adaptation of coral to environmental changes. However, coral-Symbiodinium symbiotic associations are not well-understood in the South China Sea (SCS) whilst considering environmental factors and host taxa. In this study, next-generation sequencing of the internal transcribed spacer region 2 (ITS2) marker gene was used to explore the symbiotic associations between Symbiodinium and five typical coral species across tropical and subtropical reef regions of the SCS. The results showed that Acropora sp., Galaxea fascicularis, Platygyra lamellina, and Sarcophyton glaucum exhibited distinct Symbiodinium compositions between tropical and subtropical reef regions, whereas Porites lutea had stable Symbiodinium compositions. More heterogeneous Symbiodinium compositions among different coral species were observed in the tropical region, but there were no statistically significant differences in Symbiodinium compositions among different coral species in subtropical reef regions. There was a correlation between the Symbiodinium compositions and environmental factors, except for the composition of P. lutea. Symbiodinium subclades D1, D2, C71, C71a, C21, C3b, and C161 were primarily explained by the seawater temperature, nitrate, ammonia, and phosphate. Several host-specific Symbiodinium subclades (e.g., C15, C15.6, and C91) were observed in P. lutea as well. The findings of this study demonstrate the relationship of Symbiodinium diversity with coral hosts and the environment are helpful for elucidating the adaptation of corals to global climate change and anthropogenic disturbance.},
}
@article {pmid30449358,
year = {2018},
author = {Aylward, J and Wingfield, BD and Dreyer, LL and Roets, F and Wingfield, MJ and Steenkamp, ET},
title = {Genomic overview of closely related fungi with different Protea host ranges.},
journal = {Fungal biology},
volume = {122},
number = {12},
pages = {1201-1214},
doi = {10.1016/j.funbio.2018.10.001},
pmid = {30449358},
issn = {1878-6146},
abstract = {Genome comparisons of species with distinctive ecological traits can elucidate genetic divergence that influenced their differentiation. The interaction of a microorganism with its biotic environment is largely regulated by secreted compounds, and these can be predicted from genome sequences. In this study, we considered Knoxdaviesia capensis and Knoxdaviesia proteae, two closely related saprotrophic fungi found exclusively in Protea plants. We investigated their genome structure to compare their potential inter-specific interactions based on gene content. Their genomes displayed macrosynteny and were approximately 10 % repetitive. Both species had fewer secreted proteins than pathogens and other saprotrophs, reflecting their specialized habitat. The bulk of the predicted species-specific and secreted proteins coded for carbohydrate metabolism, with a slightly higher number of unique carbohydrate-degrading proteins in the broad host-range K. capensis. These fungi have few secondary metabolite gene clusters, suggesting minimal competition with other microbes and symbiosis with antibiotic-producing bacteria common in this niche. Secreted proteins associated with detoxification and iron sequestration likely enable these Knoxdaviesia species to tolerate antifungal compounds and compete for resources, facilitating their unusual dominance. This study confirms the genetic cohesion between Protea-associated Knoxdaviesia species and reveals aspects of their ecology that have likely evolved in response to their specialist niche.},
}
@article {pmid30449353,
year = {2018},
author = {Poinar, GO and Vega, FE},
title = {A mid-Cretaceous ambrosia fungus, Paleoambrosia entomophila gen. nov. et sp. nov. (Ascomycota: Ophiostomatales) in Burmese (Myanmar) amber, and evidence for a femoral mycangium.},
journal = {Fungal biology},
volume = {122},
number = {12},
pages = {1159-1162},
doi = {10.1016/j.funbio.2018.08.002},
pmid = {30449353},
issn = {1878-6146},
abstract = {An ambrosia fungus is described from filamentous sporodochia adjacent to a wood-boring ambrosia beetle (Coleoptera: Curculionidae: Platypodinae) in mid-Cretaceous Burmese amber. Yeast-like propagules and hyphal fragments of Paleoambrosia entomophila gen. nov. et sp. nov. occur in glandular sac mycangia located inside the femur of the beetle. This is the first record of a fossil ambrosia fungus, showing that symbiotic associations between wood-boring insects and ectosymbiotic fungi date back some 100 million years ago. The present finding moves the origin of fungus-growing by insects from the Oligocene to the mid-Cretaceous and suggests a Gondwanan origin.},
}
@article {pmid30448757,
year = {2018},
author = {Ren, CG and Kong, CC and Wang, SX and Xie, ZH},
title = {Enhanced phytoremediation of uranium-contaminated soils by arbuscular mycorrhiza and rhizobium.},
journal = {Chemosphere},
volume = {217},
number = {},
pages = {773-779},
doi = {10.1016/j.chemosphere.2018.11.085},
pmid = {30448757},
issn = {1879-1298},
abstract = {Uranium phytoextraction is a promising technology, however, facing difficult that limited plant biomass due to nutrient deficiency in the contaminated sites. The aim of this study is to evaluate the potential of a symbiotic associations of a legume Sesbania rostrata, rhizobia and arbuscular mycorrhiza fungi (AMF) for reclamation of uranium contaminated soils. Results showed AMF and rhizobia had a mutual beneficial relations in the triple symbiosis, which significantly increased plant biomass and uranium accumulation in S. rostrata plant. The highest uranium removal rates was observed in plant-AMF-rhizobia treated soils, in which 50.5-73.2% had been extracted, whereas 7.2-23.3% had been extracted in plant-treated soil. Also, the S. rostrata phytochelatin synthase (PCS) genes expression were increased in AMF and rhizobia plants compared with the plants. Meantime, content of malic acid, succinic acid and citric acid were elevated in S. rostrata root exudates of AMF and rhizobia inoculated plants. The facts suggest that the mutual interactions in the triple symbiosis help to improve phytoremediation efficiency of uranium by S. rostrata.},
}
@article {pmid30447602,
year = {2018},
author = {Ma, J and Zhu, D and Chen, QL and Ding, J and Zhu, YG and Sheng, GD and Qiu, YP},
title = {Exposure to tetracycline perturbs the microbiome of soil oligochaete Enchytraeus crypticus.},
journal = {The Science of the total environment},
volume = {654},
number = {},
pages = {643-650},
doi = {10.1016/j.scitotenv.2018.11.154},
pmid = {30447602},
issn = {1879-1026},
abstract = {Microbial symbiosis is essential for the normal development and growth of hosts. Past attention has mostly been paid to its effects on plants and vertebrates. The effects of environmental pressures such as antibiotics on the microbiome of soil fauna remain largely elusive. We used bacterial 16S rRNA gene high-throughput sequencing to examine the response of microbiome of soil invertebrate Enchytraeus crypticus to oral tetracycline exposure. After two-week exposure, tetracycline-free oat was used as food to monitor the restoration of E. crypticus microbiome. The results showed that Proteobacteria, Actinobacteria and Planctomycetes were the three dominant phyla in all samples, Rhizobiaceae and Kaistia were the most abundant family and genus in all samples, respectively. After 14 days tetracycline exposure, Planctomycetes declined dramatically from 33.05% to 3.28% (P = 0.016), but Actinobacteria elevated substantially from 2.47% to 23.65% (P = 0.004). The alpha-diversity of microbial community increased significantly after tetracycline exposure compared to the control (P = 0.014). Terminating tetracycline exposure led to the recovery of E. crypticus microbiome back to the background level within 14 days. Our results suggest that while tetracycline can disturb the microbiome in E. crypticus significantly, the effects of the antibiotic on E. crypticus microbiome may not be permanent but reversibly diminish after stopping exposure for a period of time. The results may contribute to extending our understanding of the effect of antibiotics on microbiome of soil invertebrates. CAPSULE: The microbiome of E. crypticus exposed to tetracycline is perturbed and reversibly restored after terminating the exposure.},
}
@article {pmid30447333,
year = {2018},
author = {Limpens, E and Geurts, R},
title = {Transcriptional Regulation of Nutrient Exchange in Arbuscular Mycorrhizal Symbiosis.},
journal = {Molecular plant},
volume = {},
number = {},
pages = {},
doi = {10.1016/j.molp.2018.11.003},
pmid = {30447333},
issn = {1752-9867},
}
@article {pmid30443991,
year = {2018},
author = {Schneider, S and Schintlmeister, A and Becana, M and Wagner, M and Woebken, D and Wienkoop, S},
title = {Sulfate is transported at significant rates through the symbiosome membrane and is crucial for nitrogenase biosynthesis.},
journal = {Plant, cell &amp; environment},
volume = {},
number = {},
pages = {},
doi = {10.1111/pce.13481},
pmid = {30443991},
issn = {1365-3040},
abstract = {Legume-rhizobia symbioses play a major role in food production for an ever growing human population. In this symbiosis, dinitrogen is reduced ('fixed') to ammonia by the rhizobial nitrogenase enzyme complex and is secreted to the plant host cells, while dicarboxylic acids derived from photosynthetically-produced sucrose are transported into the symbiosomes and serve as respiratory substrates for the bacteroids. The symbiosome membrane contains high levels of SST1 protein, a sulfate transporter. Sulfate is an essential nutrient for all living organisms, but its importance for symbiotic nitrogen fixation and nodule metabolism has long been underestimated. Using chemical imaging, we demonstrate that the bacteroids take up 20-fold more sulfate than the nodule host cells. Furthermore, we show that nitrogenase biosynthesis relies on high levels of imported sulfate, making sulfur as essential as carbon for the regulation and functioning of symbiotic nitrogen fixation. Our findings thus establish the importance of sulfate and its active transport for the plant-microbe interaction that is most relevant for agriculture and soil fertility. This article provides a comprehensive explanation for the importance of the nodule specific sulfate transporter (SST1) and the role of sulfate by dissecting the sulfur distribution across the nodule tissue and directly linking sulfate incorporation to nitrogenase biosynthesis.},
}
@article {pmid30442721,
year = {2018},
author = {Shrestha, M and Compton, KK and Mancl, J and Webb, B and Brown, A and Scharf, B and Schubot, FD},
title = {Structure of the sensory domain of McpX from Sinorhizobium meliloti the first known bacterial chemotactic sensor for quaternary ammonium compounds.},
journal = {The Biochemical journal},
volume = {},
number = {},
pages = {},
doi = {10.1042/BCJ20180769},
pmid = {30442721},
issn = {1470-8728},
abstract = {The alpha-proteobacterium Sinorhizobium meliloti can live freely in the soil or engage in a symbiosis with its legume host. S. meliloti facilitates nitrogen-fixation in root nodules, thus providing pivotal, utilizable nitrogen to the host. The organism has eight chemoreceptors, namely McpT to McpZ and IcpA that facilitate chemotaxis. McpX is the first known bacterial sensor of quaternary amine compounds (QACs) such as choline and betaines. Because QACs are exuded at chemotaxis-relevant concentrations by germinating alfalfa seeds, McpX has been proposed to contribute to host-specific chemotaxis. We have determined the crystal structure of the McpX periplasmic region (McpXPR) in complex with the proline betaine at 2.7 Å resolution. In the crystal the protein forms a symmetric dimer with one proline betaine molecule bound to each monomer of McpXPR within membrane distal CACHE module. The ligand is bound through cation- interactions with four aromatic amino acid residues. Mutational analysis in conjunction with binding studies revealed that a conserved aspartate residue is pivotal for ligand binding. We discovered that, in a striking example of convergent evolution, the ligand binding site of McpXPR resembles that of a group of structurally unrelated betaine binding proteins including ProX and OpuAC. Through this comparison and docking studies we rationalized the specificity of McpXPR for this specific group of ligands. Collectively, our structural, biochemical, and molecular docking data have revealed the molecular determinants in McpX that are crucial for its rare ligand specificity for QACs.},
}
@article {pmid30439953,
year = {2018},
author = {Dixit, KK and Verma, S and Singh, OP and Singh, D and Singh, AP and Gupta, R and Negi, NS and Das, P and Sundar, S and Singh, R and Salotra, P},
title = {Validation of SYBR green I based closed tube loop mediated isothermal amplification (LAMP) assay and simplified direct-blood-lysis (DBL)-LAMP assay for diagnosis of visceral leishmaniasis (VL).},
journal = {PLoS neglected tropical diseases},
volume = {12},
number = {11},
pages = {e0006922},
doi = {10.1371/journal.pntd.0006922},
pmid = {30439953},
issn = {1935-2735},
abstract = {BACKGROUND: The World Health Organization has targeted elimination of visceral leishmaniasis (VL) in the Indian subcontinent (ISC) by 2020. Despite distinctive decline seen in the number of VL cases in ISC, there is still a quest for development of a diagnostic test which has the utility for detection of active infection and relapse cases and as a test of cure. The present study validated the sensitivity and specificity of SYBR Green I based closed tube LAMP assay reported by us for diagnosis of VL.<br><br>METHODOLOGY: The validation study was carried out at two endemic sites in India, located at Rajendra Memorial Research Institute of Medical Sciences (RMRIMS), Patna and Institute of Medical Sciences (IMS), Banaras Hindu University (BHU), Varanasi. Standard operating protocols were provided at the two sites for applying LAMP assay on confirmed VL cases. The diagnostic accuracy of LAMP assay was evaluated by Receiver operator curve (ROC) analysis. Furthermore, a simplified LAMP assay based on direct blood lysis, DBL-LAMP, was developed and verified for its diagnostic accuracy.<br><br>PRINCIPAL FINDINGS: A total of 267 eligible participants were included in the study which comprised of 179 VL cases and 88 controls. Sensitivity and specificity of the LAMP assay were 98.32% (95% C.I- 95.2-99.7%) and 96.59% (95% C.I.-90.4-99.3%), respectively. ROC curve analysis depicted no significant difference between area under curve (AUCROC) for LAMP assay and rK39 RDT, indicative of LAMP as an excellent diagnostic test. DBL-LAMP assay, performed on 67 VL and 100 control samples, yielded a sensitivity of 93.05% (95% C.I- 84.75-97%) and specificity of 100% (95% C.I.- 96.30-100%).<br><br>CONCLUSIONS/SIGNIFICANCE: The validated closed tube LAMP for diagnosis of VL will provide impetus to the ongoing VL elimination programme in ISC. The assay based on direct blood lysis promotes its scope for application in field settings by further reducing time and cost.},
}
@article {pmid30429501,
year = {2018},
author = {Yuyama, I and Ishikawa, M and Nozawa, M and Yoshida, MA and Ikeo, K},
title = {Transcriptomic changes with increasing algal symbiont reveal the detailed process underlying establishment of coral-algal symbiosis.},
journal = {Scientific reports},
volume = {8},
number = {1},
pages = {16802},
doi = {10.1038/s41598-018-34575-5},
pmid = {30429501},
issn = {2045-2322},
support = {14J40135//Japan Society for the Promotion of Science (JSPS)/ ; 15K18744//Japan Society for the Promotion of Science (JSPS)/ ; },
abstract = {To clarify the establishment process of coral-algal symbiotic relationships, coral transcriptome changes during increasing algal symbiont densities were examined in juvenile corals following inoculation with the algae Symbiodinium goreaui (clade C) and S. trenchii (clade D), and comparison of their transcriptomes with aposymbiotic corals by RNA-sequencing. Since Symbiodinium clades C and D showed very different rates of density increase, comparisons were made of early onsets of both symbionts, revealing that the host behaved differently for each. RNA-sequencing showed that the number of differentially-expressed genes in corals colonized by clade D increased ca. two-fold from 10 to 20 days, whereas corals with clade C showed unremarkable changes consistent with a slow rate of density increase. The data revealed dynamic metabolic changes in symbiotic corals. In addition, the endocytosis pathway was also upregulated, while lysosomal digestive enzymes and the immune system tended to be downregulated as the density of clade D algae increased. The present dataset provides an enormous number of candidate symbiosis-related molecules that exhibit the detailed process by which coral-algal endosymbiosis is established.},
}
@article {pmid30429307,
year = {2018},
author = {Georgieva, MN and Little, CTS and Bailey, RJ and Ball, AD and Glover, AG},
title = {Microbial-tubeworm associations in a 440 million year old hydrothermal vent community.},
journal = {Proceedings. Biological sciences},
volume = {285},
number = {1891},
pages = {},
doi = {10.1098/rspb.2018.2004},
pmid = {30429307},
issn = {1471-2954},
abstract = {Microorganisms are the chief primary producers within present-day deep-sea hydrothermal vent ecosystems, and play a fundamental role in shaping the ecology of these environments. However, very little is known about the microbes that occurred within, and structured, ancient vent communities. The evolutionary history, diversity and the nature of interactions between ancient vent microorganisms and hydrothermal vent animals are largely undetermined. The oldest known hydrothermal vent community that includes metazoans is preserved within the Ordovician to early Silurian Yaman Kasy massive sulfide deposit, Ural Mountains, Russia. This deposit contains two types of tube fossil attributed to annelid worms. A re-examination of these fossils using a range of microscopy, chemical analysis and nano-tomography techniques reveals the preservation of filamentous microorganisms intimately associated with the tubes. The microfossils bear a strong resemblance to modern hydrothermal vent microbial filaments, including those preserved within the mineralized tubes of the extant vent polychaete genus Alvinella The Yaman Kasy fossil filaments represent the oldest animal-microbial associations preserved within an ancient hydrothermal vent environment. They allude to a diverse microbial community, and also demonstrate that remarkable fine-scale microbial preservation can also be observed in ancient vent deposits, suggesting the possible existence of similar exceptionally preserved microfossils in even older vent environments.},
}
@article {pmid30427559,
year = {2018},
author = {Stabb, EV},
title = {Should they stay or should they go? Nitric oxide and the clash of regulators governing Vibrio fischeri biofilm formation.},
journal = {Molecular microbiology},
volume = {},
number = {},
pages = {},
doi = {10.1111/mmi.14163},
pmid = {30427559},
issn = {1365-2958},
abstract = {A key regulatory decision for many bacteria is the switch between biofilm formation and motile dispersal, and this dynamic is well illustrated in the light-organ symbiosis between the bioluminescent bacterium Vibrio fischeri and the Hawaiian bobtail squid. Biofilm formation mediated by the syp gene cluster helps V. fischeri transition from a dispersed planktonic lifestyle to a robust aggregate on the surface of the nascent symbiotic organ. However, the bacteria must then swim to pores and down into the deeper crypt tissues that they ultimately colonize. A number of positive and negative regulators control syp expression and biofilm formation, but until recently the environmental inputs controlling this clash between opposing regulatory mechanisms have been unclear. Thompson et al. have now shown that Syp-mediated biofilms can be repressed by a well known host-derived molecule: nitric oxide. This regulation is accomplished by the NO sensor HnoX exerting control over the biofilm regulator HahK. The discoveries reported here by Thompson et al. cast new light on a critical early stage of symbiotic initiation in the V. fischeri-squid model symbiosis, and more broadly it adds to a growing understanding of the role(s) that NO and HnoX play in biofilm regulation by many bacteria. This article is protected by copyright. All rights reserved.},
}
@article {pmid30425705,
year = {2018},
author = {Farkas, A and Pap, B and Kondorosi, É and Maróti, G},
title = {Antimicrobial Activity of NCR Plant Peptides Strongly Depends on the Test Assays.},
journal = {Frontiers in microbiology},
volume = {9},
number = {},
pages = {2600},
doi = {10.3389/fmicb.2018.02600},
pmid = {30425705},
issn = {1664-302X},
abstract = {The symbiosis specific NCR247 and NCR335 cationic plant peptides of Medicago truncatula have been shown to exert antimicrobial activity against a wide range of microbes. However, their antimicrobial efficiency is clearly limited by divalent cations. Here, the antibacterial and antifungal activities of NCR247 and NCR335 peptides were compared to those of the well-characterized peptide antibiotics polymyxin B and the aminoglycoside streptomycin on three model microbes, Escherichia coli, Bacillus subtilis and Saccharomyces cerevisiae as representatives of Gram-negative and Gram-positive bacteria as well as eukaryotic fungi. The aim of the study was to assess how the killing efficiency of these peptides depends on various, widely used antimicrobial susceptibility assays. Validated resazurin microdilution assay was used to determine minimal growth inhibitory concentrations in three general test media (MHB, MHBII and low-salt medium LSM). Bactericidal/fungicidal activities were determined by the commonly used drop plate assay. The natural plant peptides showed distinct characteristics, NCR247 had a generally high sensitivity for Ca2+ and Mg2+ in the medium, while NCR335 proved to be a robust and strong antimicrobial agent with comparable efficiency values to polymyxin B. Activity data were confirmed visually, both NCR247 and NCR335 treatments at minimal bactericidal concentrations induced complete disruption of the membranes and provoked cell lysis on all tested microorganisms as observed by scanning electron microscopy.},
}
@article {pmid30423115,
year = {2018},
author = {Romano, S and Ansorge, R},
title = {Scientific communication strategies of microbiologists in the era of social media.},
journal = {FEMS microbiology letters},
volume = {365},
number = {23},
pages = {},
doi = {10.1093/femsle/fny264},
pmid = {30423115},
issn = {1574-6968},
abstract = {Over the last decades, the world of communication underwent drastic changes, and internet and social media emerged as essential vehicles for exchanging information. Following these trends, it is important that scientists adapt to changes and adopt optimal strategies to communicate with colleagues, lay people and institutions. We conducted an online survey to investigate the communication strategies of microbiologists and their colleagues from other disciplines. We collected data from 527 scholars from 57 countries, with ∼42% of them being microbiologists. We focused particularly on social media and found that >80% of participants used them for work, and that ∼50% of interviewed actively shared and gathered scientific contents from social media. Compared to colleagues from other fields, microbiologists were less averse to use social media for work and were also less accustomed to use pre-prints as a source and vehicle of information. However, a large proportion of microbiologists declared to have planned pre-print publications in the future. Surprisingly, our data revealed that age is a poor predictor of social media usage, but it is strongly associated with the type of social media used, the activity undertaken on them and the attitude towards pre-print publications. Considering the kaleidoscopic variety of scientific communication tools, our data might help to optimize the scientific promotion strategies among microbiologists.},
}
@article {pmid30421109,
year = {2018},
author = {La, A and Perré, P and Taidi, B},
title = {Process for symbiotic culture of Saccharomyces cerevisiae and Chlorella vulgaris for in situ CO2 mitigation.},
journal = {Applied microbiology and biotechnology},
volume = {},
number = {},
pages = {},
doi = {10.1007/s00253-018-9506-3},
pmid = {30421109},
issn = {1432-0614},
abstract = {Industrial biotechnology relies heavily on fermentation processes that release considerable amounts of CO2. Apart from the fact that this CO2 represents a considerable part of the organic substrate, it has a negative impact on the environment. Microalgae cultures have been suggested as potential means of capturing the CO2 with further applications in high-value compounds production or directly for feed applications. We developed a sustainable process based on a mixed co-dominant culture of Saccharomyces cerevisiae and Chlorella vulgaris where the CO2 production and utilization controlled the microbial ecology of the culture. By mixing yeast and microalga in the same culture, the CO2 is produced in dissolved form and is available to the microalga avoiding degassing and dissolution phenomena. With this process, the CO2 production and utilization rates were balanced and a mutual symbiosis between the yeast and the microalga was set up in the culture. In this study, the reutilization of CO2 and growth of C. vulgaris was demonstrated. The two organism populations were balanced at approximately 20 × 106 cells ml-1 and almost all the CO2 produced by yeast was reutilized by microalga within 168 h of culture. The C. vulgaris inoculum preparation played a key role in establishing co-dominance of the two organisms. Other key factors in establishing symbiosis were the inoculum ratio of the two organisms and the growth medium design. A new method allowed the independent enumeration of each organism in a mixed culture. This study could provide a basis for the development of green processes of low environmental impact.},
}
@article {pmid30417315,
year = {2018},
author = {Kalita, M and Małek, W},
title = {The ftsA gene as a molecular marker for phylogenetic studies in Bradyrhizobium and identification of Bradyrhizobium japonicum.},
journal = {Journal of applied genetics},
volume = {},
number = {},
pages = {},
doi = {10.1007/s13353-018-0479-9},
pmid = {30417315},
issn = {2190-3883},
support = {IP2011 021571//Ministerstwo Nauki i Szkolnictwa Wyższego/ ; },
abstract = {The use of ftsA gene sequences for taxonomic studies of the genus Bradyrhizobium bacteria was assessed. The ftsA gene codes for an actin-like protein involved in prokaryotic cell division. Up to now, this gene has not been used as a phylogenetic marker for analysis of bacteria establishing root nodule symbiosis with Fabaceae plants. In this study, the ftsA gene sequences obtained for bradyrhizobia forming N2 fixing symbiosis with four Genisteae tribe plants growing in Poland and most of the type strains of the genus Bradyrhizobium species were analyzed and evaluated as molecular markers for phylogenetic studies of these bacteria for the first time. The ftsA gene sequences of all bradyrhizobial strains with completely or partially sequenced genomes, available in the GenBank database, were also included into the analysis. The phylogeny of the ftsA gene was compared to the phylogenies of other chromosomal genes commonly used in the studies of Bradyrhizobium bacteria. The results showed that the phylogenies of ftsA and the core genes recA and glnII were congruent, making the ftsA gene useful as a phylogenetic marker. Analysis of the ftsA gene sequences revealed a single-nucleotide polymorphism unique to Bradyrhizobium japonicum strains, and the potential use of this SNP for identification of this species was discussed.},
}
@article {pmid30416203,
year = {2018},
author = {Treanor, D and Pamminger, T and Hughes, WOH},
title = {The evolution of caste-biasing symbionts in the social hymenoptera.},
journal = {Insectes sociaux},
volume = {65},
number = {4},
pages = {513-519},
doi = {10.1007/s00040-018-0638-3},
pmid = {30416203},
issn = {0020-1812},
abstract = {The separation of individuals into reproductive and worker castes is the defining feature of insect societies. However, caste determination is itself a complex phenomenon, dependent on interacting genetic and environmental factors. It has been suggested by some authors that widespread maternally transmitted symbionts such as Wolbachia may be selected to interfere with caste determination, whilst others have discounted this possibility on theoretical grounds. We argue that there are in fact three distinct evolutionary scenarios in which maternally transmitted symbionts might be selected to influence the process of caste determination in a social hymenopteran host. Each of these scenarios generate testable predictions which we outline here. Given the increasing recognition of the complexity and multi-faceted nature of caste determination in social insects, we argue that maternally transmitted symbionts should also be considered as possible factors influencing the development of social hymenopterans.},
}
@article {pmid30416059,
year = {2018},
author = {Gaudioso-Pedraza, R and Beck, M and Frances, L and Kirk, P and Ripodas, C and Niebel, A and Oldroyd, GED and Benitez-Alfonso, Y and de Carvalho-Niebel, F},
title = {Callose-Regulated Symplastic Communication Coordinates Symbiotic Root Nodule Development.},
journal = {Current biology : CB},
volume = {28},
number = {22},
pages = {3562-3577.e6},
doi = {10.1016/j.cub.2018.09.031},
pmid = {30416059},
issn = {1879-0445},
abstract = {The formation of nitrogen-fixing nodules in legumes involves the initiation of synchronized programs in the root epidermis and cortex to allow rhizobial infection and nodule development. In this study, we provide evidence that symplastic communication, regulated by callose turnover at plasmodesmata (PD), is important for coordinating nodule development and infection in Medicago truncatula. Here, we show that rhizobia promote a reduction in callose levels in inner tissues where nodules initiate. This downregulation coincides with the localized expression of M. truncatula β-1,3-glucanase 2 (MtBG2), encoding a novel PD-associated callose-degrading enzyme. Spatiotemporal analyses revealed that MtBG2 expression expands from dividing nodule initials to rhizobia-colonized cortical and epidermal tissues. As shown by the transport of fluorescent molecules in vivo, symplastic-connected domains are created in rhizobia-colonized tissues and enhanced in roots constitutively expressing MtBG2. MtBG2-overexpressing roots additionally displayed reduced levels of PD-associated callose. Together, these findings suggest an active role for MtBG2 in callose degradation and in the formation of symplastic domains during sequential nodule developmental stages. Interfering with symplastic connectivity led to drastic nodulation phenotypes. Roots ectopically expressing β-1,3-glucanases (including MtBG2) exhibited increased nodule number, and those expressing MtBG2 RNAi constructs or a hyperactive callose synthase (under symbiotic promoters) showed defective nodulation phenotypes. Obstructing symplastic connectivity appears to block a signaling pathway required for the expression of NODULE INCEPTION (NIN) and its target NUCLEAR FACTOR-YA1 (NF-YA1) in the cortex. We conclude that symplastic intercellular communication is proactively enhanced by rhizobia, and this is necessary for appropriate coordination of bacterial infection and nodule development.},
}
@article {pmid30416058,
year = {2018},
author = {Decelle, J and Carradec, Q and Pochon, X and Henry, N and Romac, S and Mahé, F and Dunthorn, M and Kourlaiev, A and Voolstra, CR and Wincker, P and de Vargas, C},
title = {Worldwide Occurrence and Activity of the Reef-Building Coral Symbiont Symbiodinium in the Open Ocean.},
journal = {Current biology : CB},
volume = {28},
number = {22},
pages = {3625-3633.e3},
doi = {10.1016/j.cub.2018.09.024},
pmid = {30416058},
issn = {1879-0445},
abstract = {The dinoflagellate microalga Symbiodinium sustains coral reefs, one of the most diverse ecosystems of the biosphere, through mutualistic endosymbioses with a wide diversity of benthic hosts [1]. Despite its ecological and economic importance, the presence of Symbiodinium in open oceanic waters remains unknown, which represents a significant knowledge gap to fully understand the eco-evolutionary trajectory and resilience of endangered Symbiodinium-based symbioses. Here, we document the existence of Symbiodinium (i.e., now the family Symbiodiniaceae [2]) in tropical- and temperate-surface oceans using DNA and RNA metabarcoding of size-fractionated plankton samples collected at 109 stations across the globe. Symbiodinium from clades A and C were, by far, the most prevalent and widely distributed lineages (representing 0.1% of phytoplankton reads), while other lineages (clades B, D, E, F, and G) were present but rare. Concurrent metatranscriptomics analyses using the Tara Oceans gene catalog [3] revealed that Symbiodinium clades A and C were transcriptionally active in the open ocean and expressed core metabolic pathways (e.g., photosynthesis, carbon fixation, glycolysis, and ammonium uptake). Metabarcodes and expressed genes of clades A and C were detected in small and large plankton size fractions, suggesting the existence of a free-living population and a symbiotic lifestyle within planktonic hosts, respectively. However, high-resolution genetic markers and microscopy are required to confirm the life history of oceanic Symbiodinium. Overall, the previously unknown, metabolically active presence of Symbiodinium in oceanic waters opens up new avenues for investigating the potential of this oceanic reservoir to repopulate coral reefs following stress-induced bleaching.},
}
@article {pmid30415881,
year = {2018},
author = {Flores-Félix, JD and Sánchez-Juanes, F and García-Fraile, P and Valverde, A and Mateos, PF and Gónzalez-Buitrago, JM and Velázquez, E and Rivas, R},
title = {Phaseolus vulgaris is nodulated by the symbiovar viciae of several genospecies of Rhizobium laguerreae complex in a Spanish region where Lens culinaris is the traditionally cultivated legume.},
journal = {Systematic and applied microbiology},
volume = {},
number = {},
pages = {},
doi = {10.1016/j.syapm.2018.10.009},
pmid = {30415881},
issn = {1618-0984},
abstract = {Phaseolus vulgaris and Lens culinaris are two legumes with different distribution centers that were introduced in Spain at different times, but in some regions L. culinaris has been traditionally cultivated and P. vulgaris did not. Here we analysed the rhizobia isolated from nodules of these two legumes in one of these regions. MALDI-TOF MS analysis showed that all isolated strains matched with Rhizobium laguerreae and the phylogenetic analysis of rrs, atpD and recA genes confirmed these results. The phylogenetic analysis of these core genes allowed the differentiation of several groups within R. laguerreae and unexpectedly, strains with housekeeping genes identical to that of the type strain of R. laguerreae presented some differences in the rrs gene. In some strains this gene contains an intervening sequence (IVS) identical to that found in Rhizobium strains nodulating several legumes in different geographical locations. The atpD, recA and nodC genes of all isolated strains clustered with those of strains nodulating L. culinaris in its distribution centers, but not with those nodulating P. vulgaris in theirs. Therefore, all these strains belong to the symbiovar viciae, including those isolated from P. vulgaris, which in the studied region established effective symbiosis with the common endosymbiont of L. culinaris, instead to with its common endosymbiont, the symbiovar phaseoli. These results are particularly interesting for biogeography studies, because they showed that, due its high promiscuity degree, P. vulgaris is able to establish symbiosis with local symbiovars well established in the soil after centuries of cultivation with other legumes.},
}
@article {pmid30413093,
year = {2018},
author = {Fagorzi, C and Checcucci, A and diCenzo, GC and Debiec-Andrzejewska, K and Dziewit, L and Pini, F and Mengoni, A},
title = {Harnessing Rhizobia to Improve Heavy-Metal Phytoremediation by Legumes.},
journal = {Genes},
volume = {9},
number = {11},
pages = {},
doi = {10.3390/genes9110542},
pmid = {30413093},
issn = {2073-4425},
support = {2017-0719//Fondazione Cassa di Risparmio di Firenze/ ; Dinamiche dell'evoluzione dei genomi batterici: l'evoluzione del genoma multipartito e la suddivisione in moduli funzionali//Università degli Studi di Firenze/ ; PDF to GDC//Natural Sciences and Engineering Research Council of Canada (NSERC)/ ; 7376//EMBO Short-Term Fellowship program/ ; 2016/23/N/NZ9/01655//National Science Center (Poland)/ ; },
abstract = {Rhizobia are bacteria that can form symbiotic associations with plants of the Fabaceae family, during which they reduce atmospheric di-nitrogen to ammonia. The symbiosis between rhizobia and leguminous plants is a fundamental contributor to nitrogen cycling in natural and agricultural ecosystems. Rhizobial microsymbionts are a major reason why legumes can colonize marginal lands and nitrogen-deficient soils. Several leguminous species have been found in metal-contaminated areas, and they often harbor metal-tolerant rhizobia. In recent years, there have been numerous efforts and discoveries related to the genetic determinants of metal resistance by rhizobia, and on the effectiveness of such rhizobia to increase the metal tolerance of host plants. Here, we review the main findings on the metal resistance of rhizobia: the physiological role, evolution, and genetic determinants, and the potential to use native and genetically-manipulated rhizobia as inoculants for legumes in phytoremediation practices.},
}
@article {pmid30411190,
year = {2018},
author = {Rossi, A and Bellone, A and Fokin, SI and Boscaro, V and Vannini, C},
title = {Detecting Associations Between Ciliated Protists and Prokaryotes with Culture-Independent Single-Cell Microbiomics: a Proof-of-Concept Study.},
journal = {Microbial ecology},
volume = {},
number = {},
pages = {},
doi = {10.1007/s00248-018-1279-9},
pmid = {30411190},
issn = {1432-184X},
support = {565-60%2016//University of Pisa/ ; 565-60%2017//University of Pisa/ ; 565-FFABR 2017//Ministero dell'Istruzione, dell'Università e della Ricerca/ ; },
abstract = {Symbioses between prokaryotes and microbial eukaryotes, particularly ciliated protists, have been studied for a long time. Nevertheless, researchers have focused only on a few host genera and species, mainly due to difficulties in cultivating the hosts, and usually have considered a single symbiont at a time. Here, we present a pilot study using a single-cell microbiomic approach to circumvent these issues. Unicellular ciliate isolation followed by simultaneous amplification of eukaryotic and prokaryotic markers was used. Our preliminary test gave reliable and satisfactory results both on samples collected from different habitats (marine and freshwater) and on ciliates belonging to different taxonomic groups. Results suggest that, as already assessed for many macro-organisms like plants and metazoans, ciliated protists harbor distinct microbiomes. The applied approach detected new potential symbionts as well as new hosts for previously described ones, with relatively low time and cost effort and without culturing. When further developed, single-cell microbiomics for ciliates could be applied to a large number of studies aiming to unravel the evolutionary and ecological meaning of these symbiotic systems.},
}
@article {pmid30410727,
year = {2018},
author = {Morris, JJ},
title = {What is the hologenome concept of evolution?.},
journal = {F1000Research},
volume = {7},
number = {},
pages = {},
doi = {10.12688/f1000research.14385.1},
pmid = {30410727},
issn = {2046-1402},
abstract = {All multicellular organisms are colonized by microbes, but a gestalt study of the composition of microbiome communities and their influence on the ecology and evolution of their macroscopic hosts has only recently become possible. One approach to thinking about the topic is to view the host-microbiome ecosystem as a &quot;holobiont&quot;. Because natural selection acts on an organism's realized phenotype, and the phenotype of a holobiont is the result of the integrated activities of both the host and all of its microbiome inhabitants, it is reasonable to think that evolution can act at the level of the holobiont and cause changes in the &quot;hologenome&quot;, or the collective genomic content of all the individual bionts within the holobiont. This relatively simple assertion has nevertheless been controversial within the microbiome community. Here, I provide a review of recent work on the hologenome concept of evolution. I attempt to provide a clear definition of the concept and its implications and to clarify common points of disagreement.},
}
@article {pmid30410449,
year = {2018},
author = {Colella, S and Parisot, N and Simonet, P and Gaget, K and Duport, G and Baa-Puyoulet, P and Rahbé, Y and Charles, H and Febvay, G and Callaerts, P and Calevro, F},
title = {Bacteriocyte Reprogramming to Cope With Nutritional Stress in a Phloem Sap Feeding Hemipteran, the Pea Aphid Acyrthosiphon pisum.},
journal = {Frontiers in physiology},
volume = {9},
number = {},
pages = {1498},
doi = {10.3389/fphys.2018.01498},
pmid = {30410449},
issn = {1664-042X},
abstract = {Nutritional symbioses play a central role in the ability of insects to thrive on unbalanced diets and in ensuring their evolutionary success. A genomic model for nutritional symbiosis comprises the hemipteran Acyrthosiphon pisum, and the gamma-3-proteobacterium, Buchnera aphidicola, with genomes encoding highly integrated metabolic pathways. A. pisum feeds exclusively on plant phloem sap, a nutritionally unbalanced diet highly variable in composition, thus raising the question of how this symbiotic system responds to nutritional stress. We addressed this by combining transcriptomic, phenotypic and life history trait analyses to determine the organismal impact of deprivation of tyrosine and phenylalanine. These two aromatic amino acids are essential for aphid development, are synthesized in a metabolic pathway for which the aphid host and the endosymbiont are interdependent, and their concentration can be highly variable in plant phloem sap. We found that this nutritional challenge does not have major phenotypic effects on the pea aphid, except for a limited weight reduction and a 2-day delay in onset of nymph laying. Transcriptomic analyses through aphid development showed a prominent response in bacteriocytes (the core symbiotic tissue which houses the symbionts), but not in gut, thus highlighting the role of bacteriocytes as major modulators of this homeostasis. This response does not involve a direct regulation of tyrosine and phenylalanine biosynthetic pathway and transporter genes. Instead, we observed an extensive transcriptional reprogramming of the bacteriocyte with a rapid down-regulation of genes encoding sugar transporters and genes required for sugar metabolism. Consistently, we observed continued overexpression of the A. pisum homolog of RRAD, a small GTPase implicated in repressing aerobic glycolysis. In addition, we found increased transcription of genes involved in proliferation, cell size control and signaling. We experimentally confirmed the significance of these gene expression changes detecting an increase in bacteriocyte number and cell size in vivo under tyrosine and phenylalanine depletion. Our results support a central role of bacteriocytes in the aphid response to amino acid deprivation: their transcriptional and cellular responses fine-tune host physiology providing the host insect with an effective way to cope with the challenges posed by the variability in composition of phloem sap.},
}
@article {pmid30410018,
year = {2018},
author = {Roth, R and Chiapello, M and Montero, H and Gehrig, P and Grossmann, J and O'Holleran, K and Hartken, D and Walters, F and Yang, SY and Hillmer, S and Schumacher, K and Bowden, S and Craze, M and Wallington, EJ and Miyao, A and Sawers, R and Martinoia, E and Paszkowski, U},
title = {A rice Serine/Threonine receptor-like kinase regulates arbuscular mycorrhizal symbiosis at the peri-arbuscular membrane.},
journal = {Nature communications},
volume = {9},
number = {1},
pages = {4677},
doi = {10.1038/s41467-018-06865-z},
pmid = {30410018},
issn = {2041-1723},
abstract = {In terrestrial ecosystems most plant species live in mutualistic symbioses with nutrient-delivering arbuscular mycorrhizal (AM) fungi. Establishment of AM symbioses includes transient, intracellular formation of fungal feeding structures, the arbuscules. A plant-derived peri-arbuscular membrane (PAM) surrounds the arbuscules, mediating reciprocal nutrient exchange. Signaling at the PAM must be well coordinated to achieve this dynamic cellular intimacy. Here, we identify the PAM-specific Arbuscular Receptor-like Kinase 1 (ARK1) from maize and rice to condition sustained AM symbiosis. Mutation of rice ARK1 causes a significant reduction in vesicles, the fungal storage structures, and a concomitant reduction in overall root colonization by the AM fungus Rhizophagus irregularis. Arbuscules, although less frequent in the ark1 mutant, are morphologically normal. Co-cultivation with wild-type plants restores vesicle and spore formation, suggesting ARK1 function is required for the completion of the fungal life-cycle, thereby defining a functional stage, post arbuscule development.},
}
@article {pmid30408885,
year = {2019},
author = {Parakh, SK and Praveen, P and Loh, KC and Tong, YW},
title = {Wastewater treatment and microbial community dynamics in a sequencing batch reactor operating under photosynthetic aeration.},
journal = {Chemosphere},
volume = {215},
number = {},
pages = {893-903},
doi = {10.1016/j.chemosphere.2018.10.085},
pmid = {30408885},
issn = {1879-1298},
abstract = {A sequencing batch bioreactor (SBR) treating municipal wastewater was photosynthetically aerated using microalgae cultivated in a photobioreactor (PBR). Symbiotic interactions and CO2/O2 exchange were established between activated sludge in the SBR and microalgae in the PBR through hydrophobic hollow fiber membranes. Photosynthetic aeration enhanced COD removal in the SBR from 52.2% (without external aeration) to 90.3%, whereas N-NH4+ and P-PO43- removal increased by 63.5% and 90.4%, respectively. The SBR performance under photosynthetic aeration was comparable to that under mechanical aeration. However, no nitrification was observed in the SBR, indicating oxygen limitation and poor growth condition for nitrifiers. In the PBR, there was a rapid increase in biomass concentration and it stabilized at 3.0 g/L after 22 days of operation. High nitrogen demand in the PBR indicated the steady flow of inorganic carbon from the SBR through the membranes. Prolonged oxygen limitation and massive sludge attachment on the membranes resulted in low suspended sludge concentration in the SBR. Microbial community analysis indicated gradual enrichment of facultative and strictly anaerobic microorganisms in the SBR. These results highlight the potential of microalgae in lowering the cost of wastewater aeration and underline the challenges in sustaining symbiotic gas exchange during long-term.},
}
@article {pmid30405668,
year = {2018},
author = {Buendia, L and Girardin, A and Wang, T and Cottret, L and Lefebvre, B},
title = {LysM Receptor-Like Kinase and LysM Receptor-Like Protein Families: An Update on Phylogeny and Functional Characterization.},
journal = {Frontiers in plant science},
volume = {9},
number = {},
pages = {1531},
doi = {10.3389/fpls.2018.01531},
pmid = {30405668},
issn = {1664-462X},
abstract = {Members of plant specific families of receptor-like kinases (RLKs) and receptor-like proteins (RLPs), containing 3 extracellular LysMs have been shown to directly bind and/or to be involved in perception of lipo-chitooligosaccharides (LCO), chitooligosaccharides (CO), and peptidoglycan (PGN), three types of GlcNAc-containing molecules produced by microorganisms. These receptors are involved in microorganism perception by plants and can activate different plant responses leading either to symbiosis establishment or to defense responses against pathogens. LysM-RLK/Ps belong to multigenic families. Here, we provide a phylogeny of these families in eight plant species, including dicotyledons and monocotyledons, and we discuss known or putative biological roles of the members in each of the identified phylogenetic groups. We also report and discuss known biochemical properties of the LysM-RLK/Ps.},
}
@article {pmid30404651,
year = {2018},
author = {Hujber, Z and Horváth, G and Petővári, G and Krencz, I and Dankó, T and Mészáros, K and Rajnai, H and Szoboszlai, N and Leenders, WPJ and Jeney, A and Tretter, L and Sebestyén, A},
title = {GABA, glutamine, glutamate oxidation and succinic semialdehyde dehydrogenase expression in human gliomas.},
journal = {Journal of experimental &amp; clinical cancer research : CR},
volume = {37},
number = {1},
pages = {271},
doi = {10.1186/s13046-018-0946-5},
pmid = {30404651},
issn = {1756-9966},
support = {Bolyai Fellowship Program//Hungarian Academy of Sciences/ ; Scientific and Innovative Research Found of Semmelweis University//Semmelweis University/ ; New National Excellence Program ÚNKP-17/2//Ministry of Human Capacities - Hungary/ ; New National Excellence Program ÚNKP-17/3 and ÚNKP-18/3//Ministry of Human Capacities - Hungary/ ; New National Excellence Program - ÚNKP-17/3 and ÚNKP-18/3//Ministry of Human Capacities - Hungary/ ; Richter Centenarium Foundation Fellowship-2016//Richter Centenarium Foundation/ ; NVKP_16-1-2016-0004 grant//Hungarian National Research, Development and Innovation Office (NKFIH)/ ; },
abstract = {BACKGROUND: Bioenergetic characterisation of malignant tissues revealed that different tumour cells can catabolise multiple substrates as salvage pathways, in response to metabolic stress. Altered metabolism in gliomas has received a lot of attention, especially in relation to IDH mutations, and the associated oncometabolite D-2-hydroxyglutarate (2-HG) that impact on metabolism, epigenetics and redox status. Astrocytomas and oligodendrogliomas, collectively called diffuse gliomas, are derived from astrocytes and oligodendrocytes that are in metabolic symbiosis with neurons; astrocytes can catabolise neuron-derived glutamate and gamma-aminobutyric acid (GABA) for supporting and regulating neuronal functions.<br><br>METHODS: Metabolic characteristics of human glioma cell models - including mitochondrial function, glycolytic pathway and energy substrate oxidation - in relation to IDH mutation status and after 2-HG incubation were studied to understand the Janus-faced role of IDH1 mutations in the progression of gliomas/astrocytomas. The metabolic and bioenergetic features were identified in glioma cells using wild-type and genetically engineered IDH1-mutant glioblastoma cell lines by metabolic analyses with Seahorse, protein expression studies and liquid chromatography-mass spectrometry.<br><br>RESULTS: U251 glioma cells were characterised by high levels of glutamine, glutamate and GABA oxidation. Succinic semialdehyde dehydrogenase (SSADH) expression was correlated to GABA oxidation. GABA addition to glioma cells increased proliferation rates. Expression of mutated IDH1 and treatment with 2-HG reduced glutamine and GABA oxidation, diminished the pro-proliferative effect of GABA in SSADH expressing cells. SSADH protein overexpression was found in almost all studied human cases with no significant association between SSADH expression and clinicopathological parameters (e.g. IDH mutation).<br><br>CONCLUSIONS: Our findings demonstrate that SSADH expression may participate in the oxidation and/or consumption of GABA in gliomas, furthermore, GABA oxidation capacity may contribute to proliferation and worse prognosis of gliomas. Moreover, IDH mutation and 2-HG production inhibit GABA oxidation in glioma cells. Based on these data, GABA oxidation and SSADH activity could be additional therapeutic targets in gliomas/glioblastomas.},
}
@article {pmid30404159,
year = {2018},
author = {Wang, T and Song, Z and Wang, X and Xu, L and Sun, Q and Li, L},
title = {Functional Insights into the Roles of Hormones in the Dendrobium officinale-Tulasnella sp. Germinated Seed Symbiotic Association.},
journal = {International journal of molecular sciences},
volume = {19},
number = {11},
pages = {},
doi = {10.3390/ijms19113484},
pmid = {30404159},
issn = {1422-0067},
support = {Z171100001417006//Beijing Science and Technology Projects of China/ ; },
abstract = {Dendrobium is one of the largest genera in the Orchidaceae, and D. officinale is used in traditional medicine, particularly in China. D. officinale seeds are minute and contain limited energy reserves, and colonization by a compatible fungus is essential for germination under natural conditions. When the orchid mycorrhizal fungi (OMF) initiates symbiotic interactions with germination-driven orchid seeds, phytohormones from the orchid or the fungus play key roles, but the details of the possible biochemical pathways are still poorly understood. In the present study, we established a symbiotic system between D. officinale and Tulasnella sp. for seed germination. RNA-Seq was used to construct libraries of symbiotic-germinated seeds (DoTc), asymbiotic-germinated seeds (Do), and free-living OMF (Tc) to investigate the expression profiles of biosynthesis and metabolism pathway genes for three classes of endogenous hormones: JA (jasmonic acid), ABA (abscisic acid) and SLs (strigolactones), in D. officinale seeds and OMF under symbiotic and asymbiotic conditions. Low concentrations of endogenous JA, ABA, or SLs were detected in the D. officinale-Tulasnella symbiont compared with the asymbiotic tissues. Gene annotation results suggest that the expression of DEGs (differentially expressed genes) related to JA and ABA biosynthesis from D. officinale were down-regulated, while most of the key DEGs related to SL biosynthesis from D. officinale were up-regulated in the symbiotic germinated seeds compared with the asymbiotic germinated seeds. Moreover, in the OMF, we found a significantly up-regulated differential expression of the JA and ABA biosynthesis-related genes in the symbiotic interaction, with the opposite expression trends to those found in Dendrobium. This indicates that Dendrobium seed symbiotic germination may be stimulated by the apparent involvement of the OMF in the production of hormones, and relatively low concentrations of endogenous JA, ABA, or SLs might be maintained to promote the growth of the D. officinale-Tulasnella symbiotic protocorm-like body. These results will increase our understanding of the possible roles played by endogenous hormones in the regulation of the orchid-fungus symbiosis.},
}
@article {pmid30403490,
year = {2018},
author = {Somporn, P and Walters, L and Ash, J},
title = {Expectations of rural community-based medical education: a case study from Thailand.},
journal = {Rural and remote health},
volume = {18},
number = {4},
pages = {4709},
doi = {10.22605/RRH4709},
pmid = {30403490},
issn = {1445-6354},
abstract = {INTRODUCTION: Thailand has recognised and sought to remedy rural medical workforce shortages. The Collaborative Project to Increase Production of Rural Doctors (CPIRD) has improved rural workforce recruitment through publicly funding medical school places for students with rural backgrounds. However, challenges in rural retention continue. CPIRD is seeking to develop a Thai rural community-based medical education (RCBME) program in the southern region of Thailand to improve preparation for rural practice and rural medical retention rates. Prospective stakeholder consultations will allow the understanding of expectations and concerns of stakeholders required for successful RCBME implementation. This study aims to explore stakeholders' expectations of the Southern Thai RCBME initiative.<br><br>METHODS: A qualitative case study comprised a purposive sample of students, clinical educators, policymakers, rural health professionals and local community stakeholders, all likely to be involved in a new RCBME program in Songkhla Province, Thailand. Individual semi-structured interviews were audiotaped, transcribed in Thai and coded using Worley's symbiosis framework. Following this, text and quotes used in the initial analysis were translated into English, discussed and reanalysed for emergent themes across the framework.<br><br>RESULTS: A total of 21 participants contributed RCBME stakeholder perspectives. They demonstrated expectations and concerns in each of the relationship axes of the symbiosis model including the clinical, institutional, social and personal axes. Three major themes emerged from the data that integrated stakeholder perspectives on the implication of RCBME in Thailand. These themes were a dramatic shift in Thai medical education paradigm, seeing rural practice as a future career, and collaboration to improve education and health in rural services.<br><br>CONCLUSION: This study comprehensively describes Thai stakeholder expectations of RCBME and demonstrates that, although some principles of RCBME are universal, context does influence the expectations and capacity of stakeholders to contribute to RCBME. Prospective formal stakeholder engagement is recommended to ensure successful implementation of new educational innovations.},
}
@article {pmid30403423,
year = {2018},
author = {Sepp, SK and Davison, J and Jairus, T and Vasar, M and Moora, M and Zobel, M and Öpik, M},
title = {Non-random association patterns in a plant-mycorrhizal fungal network reveal host-symbiont specificity.},
journal = {Molecular ecology},
volume = {},
number = {},
pages = {},
doi = {10.1111/mec.14924},
pmid = {30403423},
issn = {1365-294X},
abstract = {Arbuscular mycorrhizal (AM) fungi are obligate plant symbionts that have important functions in most terrestrial ecosystems, but there remains an incomplete understanding of host-fungus specificity and the relationships between species or functional groups of plants and AM fungi. Here, we aimed to provide a comprehensive description of plant-AM fungal interactions in a biodiverse semi-natural grassland. We sampled all plant species in a 1000 m2 homogeneous plot of dry calcareous grassland in two seasons (summer and autumn) and identified root-colonizing AM fungi by SSU rDNA sequencing. In the network of 33 plant and 100 AM fungal species, we found a significant effect of both host plant species and host plant functional group on AM fungal richness and community composition. Comparison with network null models revealed a larger-than-random degree of partner selectivity among plants. Grasses harbored a larger number of AM fungal partners and were more generalist in partner selection, compared with forbs. More generalist partner association and lower specialization were apparent among obligately, compared with facultatively, mycorrhizal plant species and among locally more abundant plant species. This study provides the most complete dataset of co-occurring plant and AM fungal taxa to date, showing that at this particular site, the interaction network is assembled non-randomly, with moderate selectivity in associations between plant species and functional groups and their fungal symbionts. This article is protected by copyright. All rights reserved.},
}
@article {pmid30403141,
year = {2018},
author = {Joshi, S and Cook, E and Mannoor, MS},
title = {Bacterial Nanobionics via 3D Printing.},
journal = {Nano letters},
volume = {},
number = {},
pages = {},
doi = {10.1021/acs.nanolett.8b02642},
pmid = {30403141},
issn = {1530-6992},
abstract = {Investigating the multidimensional integration between different microbiological kingdoms possesses potential toward engineering next-generation bionic architectures. Bacterial and fungal kingdom exhibits mutual symbiosis that can offer advanced functionalities to these bionic architectures. Moreover, functional nanomaterials can serve as probing agents for accessing newer information from microbial organisms due to their dimensional similarities. In this article, a bionic mushroom was created by intertwining cyanobacterial cells with graphene nanoribbons (GNRs) onto the umbrella-shaped pileus of mushroom for photosynthetic bioelectricity generation. These seamlessly merged GNRs function as agents for mediating extracellular electron transport from cyanobacteria resulting in photocurrent generation. Additionally, three-dimensional (3D) printing technique was used to assemble cyanobacterial cells in anisotropic, densely packed geometry resulting in adequate cell-population density for efficient collective behavior. These 3D printed cyanobacterial colonies resulted in comparatively higher photocurrent (almost 8-fold increase) than isotropically casted cyanobacteria of similar seeding density. An insight of the proposed integration between cyanobacteria and mushroom derives remarkable advantage that arises from symbiotic relationship, termed here as engineered bionic symbiosis. Existence of this engineered bionic symbiosis was confirmed by UV-visible spectroscopy and standard plate counting method. Taken together, the present study augments scientific understanding of multidimensional integration between the living biological microworld and functional abiotic nanomaterials to establish newer dimensionalities toward advancement of bacterial nanobionics.},
}
@article {pmid30402759,
year = {2018},
author = {Chashchina, OE and Chibilev, AA and Veselkin, DV and Kuyantseva, NB and Mumber, AG},
title = {The Natural Abundance of Heavy Nitrogen Isotope (15N) in Plants Increases near a Large Copper Smelter.},
journal = {Doklady biological sciences : proceedings of the Academy of Sciences of the USSR, Biological sciences sections},
volume = {482},
number = {1},
pages = {198-201},
doi = {10.1134/S0012496618050083},
pmid = {30402759},
issn = {1608-3105},
abstract = {The ratio of stable isotopes of nitrogen (15N and 14N) has been assessed in leaves of the forest plants from different functional groups (with ectomycorrhiza, ericoid, and arbuscular mycorrhiza; in a nitrogen-fixing symbiosis) under the conditions of strong transformation of ecosystems by the Karabashsky Copper-Smelting Plant effluents in the Southern Urals. The abundance of 15N in the plants generally increases in polluted habitats. The abundance of the heavy isotope 15N increases significantly with pollution in ericaceous dwarf shrubs (by 3.3‰) and herbs with arbuscular mycorrhizae (by 2.8‰). This indicates a strong alteration in conditions or modes of plant mineral nutrition under the influence of heavy metal pollution of forest ecosystems.},
}
@article {pmid30402695,
year = {2018},
author = {Alvarado-López, CJ and Dasgupta-Schubert, N and Ambriz, JE and Arteaga-Velazquez, JC and Villegas, JA},
title = {Lead uptake by the symbiotic Daucus carota L.-Glomus intraradices system and its effect on the morphology of extra- and intraradical fungal microstructures.},
journal = {Environmental science and pollution research international},
volume = {},
number = {},
pages = {},
doi = {10.1007/s11356-018-3569-7},
pmid = {30402695},
issn = {1614-7499},
support = {168355//CONACyT/ ; },
abstract = {This work examines the strategies adopted by an arbuscular mycorrhizal symbiotic system to ameliorate environmental Pb stress by examining the concentrations of P, Fe, and Pb in the fungal microstructures and the host's root. In vitro cultures of Ri-T DNA-transformed carrot (Daucus carota L.) roots were inoculated with Glomus intraradices and treated with Pb(NO3)2 solution and the extraradical spores and mycelia (S/M) and the root with the vesicles, mycelia, and root cells were subsequently analyzed by polarized energy dispersive x-ray fluorescence (PEDXRF) spectrometry. Upon Pb treatment, within the root, the percentages of mycorrhizal colonization, the vesicles, and mycelia increased as well as the areas of the vesicles and the (extraradical) spores, although the number of spores and arbuscules decreased. The S/M and the mycorrhizal root showed enhanced concentrations of Pb, Fe, and P. These were particularly marked for Fe in the Pb-treated cultures. This indicates a synergistic relationship between the arbuscular mycorrhizal fungus and the host that confers a higher Pb tolerance to the latter by the induction of higher Fe absorption in the host. The intraradical vesicle, mycelia, and arbuscule numbers are interpreted as a &quot;tactic to divert&quot; the intraradical Pb traffic away from the root cells to the higher affinity cell walls of the arbuscular mycorrhizal fungi (AMF) microstructures in the apoplast. The results of this work show that the symbiosis between the AMF G. intraradices and the host plant D. carota distinctly improves the latter's Pb tolerance, and imply that the appropriate metal tolerant host-AMF combinations could be employed in process designs for the phytoremediation of Pb.},
}
@article {pmid30401930,
year = {2018},
author = {Jones, VAS and Bucher, M and Hambleton, EA and Guse, A},
title = {Microinjection to deliver protein, mRNA, and DNA into zygotes of the cnidarian endosymbiosis model Aiptasia sp.},
journal = {Scientific reports},
volume = {8},
number = {1},
pages = {16437},
doi = {10.1038/s41598-018-34773-1},
pmid = {30401930},
issn = {2045-2322},
support = {LTF//European Molecular Biology Organization (EMBO)/ ; GU 1128/3-1//Deutsche Forschungsgemeinschaft (German Research Foundation)/ ; 724715//EC | European Research Council (ERC)/ ; },
abstract = {Reef-building corals depend on an intracellular symbiosis with photosynthetic dinoflagellates for their survival in nutrient-poor oceans. Symbionts are phagocytosed by coral larvae from the environment and transfer essential nutrients to their hosts. Aiptasia, a small tropical marine sea anemone, is emerging as a tractable model system for coral symbiosis; however, to date functional tools and genetic transformation are lacking. Here we have established an efficient workflow to collect Aiptasia eggs for in vitro fertilization and microinjection as the basis for experimental manipulations in the developing embryo and larvae. We demonstrate that protein, mRNA, and DNA can successfully be injected into live Aiptasia zygotes to label actin with recombinant Lifeact-eGFP protein; to label nuclei and cell membranes with NLS-eGFP and farnesylated mCherry translated from injected mRNA; and to transiently drive transgene expression from an Aiptasia-specific promoter, respectively, in embryos and larvae. These proof-of-concept approaches pave the way for future functional studies of development and symbiosis establishment in Aiptasia, a powerful model to unravel the molecular mechanisms underlying intracellular coral-algal symbiosis.},
}
@article {pmid30400148,
year = {2018},
author = {Wang, J and Wang, J and Liu, C and Ma, C and Li, C and Zhang, Y and Qi, Z and Zhu, R and Shi, Y and Zou, J and Li, Q and Zhu, J and Wen, Y and Sun, Z and Liu, H and Jiang, H and Yin, Z and Hu, Z and Chen, Q and Wu, X and Xin, D},
title = {Identification of Soybean Genes Whose Expression is Affected by the Ensifer fredii HH103 Effector Protein NopP.},
journal = {International journal of molecular sciences},
volume = {19},
number = {11},
pages = {},
doi = {10.3390/ijms19113438},
pmid = {30400148},
issn = {1422-0067},
support = {2017YFE0111000//The Ministry of Science and Technology of People's Republic of China/ ; 31400074//The National Natural Science Foundation/ ; 31471516//the National Natural Science Foundation of China/ ; 31271747//the National Natural Science Foundation of China/ ; 30971809//the National Natural Science Foundation of China/ ; ZD201213//the Natural Science Foundation of Heilongjiang Province of China/ ; LBH-Q16014//the Heilongjiang Postdoctoral Science Foundation/ ; 2013RFQXJ005//Harbin Science Technology Project/ ; 2014RFXXJ012//Harbin Science Technology Project/ ; 2016YFD0100500//the National Key R&amp;D Program of China/ ; 2016YFD0100300//the National Key R&amp;D Program of China/ ; 2016YFD0100201-21//the National Key R&amp;D Program of China/ ; 1254G011//Foundation for University Key Teachers from the education department of Heilongjiang Province in China/ ; },
abstract = {In some legume⁻rhizobium symbioses, host specificity is influenced by rhizobial nodulation outer proteins (Nops). However, the genes encoding host proteins that interact with Nops remain unknown. We generated an Ensifer fredii HH103 NopP mutant (HH103ΩNopP), and analyzed the nodule number (NN) and nodule dry weight (NDW) of 10 soybean germplasms inoculated with the wild-type E. fredii HH103 or the mutant strain. An analysis of recombinant inbred lines (RILs) revealed the quantitative trait loci (QTLs) associated with NopP interactions. A soybean genomic region containing two overlapping QTLs was analyzed in greater detail. A transcriptome analysis and qRT-PCR assay were used to identify candidate genes encoding proteins that interact with NopP. In some germplasms, NopP positively and negatively affected the NN and NDW, while NopP had different effects on NN and NDW in other germplasms. The QTL region in chromosome 12 was further analyzed. The expression patterns of candidate genes Glyma.12g031200 and Glyma.12g073000 were determined by qRT-PCR, and were confirmed to be influenced by NopP.},
}
@article {pmid30399353,
year = {2018},
author = {Wiedenmann, J and D'Angelo, C},
title = {Symbiosis: High-Carb Diet of Reef Corals as Seen from Space.},
journal = {Current biology : CB},
volume = {28},
number = {21},
pages = {R1263-R1265},
doi = {10.1016/j.cub.2018.09.056},
pmid = {30399353},
issn = {1879-0445},
abstract = {High levels of phytoplankton visible in satellite imagery are correlated with an increased uptake of carbon compounds by corals. This suggests that corals rely less on carbon production by photosynthetic symbionts when other resources are plentiful, and that the changes in the acquisition mode of carbon can be inferred by remote-sensing techniques.},
}
@article {pmid30395788,
year = {2018},
author = {Xu, Y and Liu, F and Li, X and Cheng, B},
title = {The mycorrhiza-induced maize ZmPt9 gene affects root development and phosphate availability in nonmycorrhizal plant.},
journal = {Plant signaling &amp; behavior},
volume = {},
number = {},
pages = {1-3},
doi = {10.1080/15592324.2018.1542240},
pmid = {30395788},
issn = {1559-2324},
abstract = {The arbuscular mycorrhizal (AM)-induced ZmPt9 gene is an orthologous to some AM-inducible phosphate (Pi) transporter genes involved in Pi-starvation responses. Promoter GFP assay confirmed its transcript was localized surrounding arbuscule in arbuscule-containing cells. But this gene was not an AM fungi-specific gene. Its function in nonmycorrhizal seedlings was verified through phenotypic analysis of ZmPt9-overexpression Arabidopsis. Overexpression of ZmPt9 in Arabidopsis exhibited increased primary root length and lateral root formation. Furthermore, ZmPt9-overexpression Arabidopsis plants contained more phosphorus (P) than that of wild type. The affection of ZmPt9 in nonmycorrhizal Arabidopsis leads to the hypothesis that symbiosis-inducible genes are also involved in root development and Pi accumulation in AM-independent manner.},
}
@article {pmid30392013,
year = {2018},
author = {Hendrikx, T and Schnabl, B},
title = {Antimicrobial proteins: intestinal guards to protect against liver disease.},
journal = {Journal of gastroenterology},
volume = {},
number = {},
pages = {},
doi = {10.1007/s00535-018-1521-8},
pmid = {30392013},
issn = {1435-5922},
support = {R01 AA020703/AA/NIAAA NIH HHS/United States ; R01 AA024726/AA/NIAAA NIH HHS/United States ; U01 AA021856/AA/NIAAA NIH HHS/United States ; U01 AA024726/AA/NIAAA NIH HHS/United States ; U01 AA026939/AA/NIAAA NIH HHS/United States ; },
abstract = {Alterations of gut microbes play a role in the pathogenesis and progression of many disorders including liver and gastrointestinal diseases. Both qualitative and quantitative changes in gut microbiota have been associated with liver disease. Intestinal dysbiosis can disrupt the integrity of the intestinal barrier leading to pathological bacterial translocation and the initiation of an inflammatory response in the liver. In order to sustain symbiosis and protect from pathological bacterial translocation, antimicrobial proteins (AMPs) such as a-defensins and C-type lectins are expressed in the gastrointestinal tract. In this review, we provide an overview of the role of AMPs in different chronic liver disease such as alcoholic steatohepatitis, non-alcoholic fatty liver disease, and cirrhosis. In addition, potential approaches to modulate the function of AMPs and prevent bacterial translocation are discussed.},
}
@article {pmid30390540,
year = {2018},
author = {Meng, F and Xi, L and Liu, D and Huang, W and Lei, Z and Zhang, Z and Huang, W},
title = {Effects of light intensity on oxygen distribution, lipid production and biological community of algal-bacterial granules in photo-sequencing batch reactors.},
journal = {Bioresource technology},
volume = {272},
number = {},
pages = {473-481},
doi = {10.1016/j.biortech.2018.10.059},
pmid = {30390540},
issn = {1873-2976},
abstract = {The effects of light intensity (0-225 µmol m-2 s-1) on oxygen distribution, lipid production and biological community structure of algal-bacterial granules were investigated in six identical photo-sequencing batch reactors (with a dark/light cycle of 12 h/12 h). Typically green algal-bacterial granules could be developed at a light intensity of ≥135 µmol m-2 s-1. The lipid content was significantly increased under higher light intensity, while the percentage of saturated fatty acid methyl esters was remarkably decreased. Results showed that light intensity ≥90 µmol m-2 s-1 yielded enough O2 production from algae, creating aerobic/anoxic zone (0.3-0.6 mg-O2/L) in the core of granules and thus efficient algal-bacterial symbiosis system. Enhanced nitrogen and phosphorus removals were achieved in the reactors with stronger light illumination, probably attributable to the enrichment of ammonia oxidizing bacteria (Comamonadaceae and Nitrosomonadaceae) and algae (Navicula and Stigeoclonium). Illuminance ≥180 µmol m-2 s-1 was found to be unfavorable for Nitrospiraceae.},
}
@article {pmid30390012,
year = {2018},
author = {Kim, TH and Kim, D and Gautam, A and Lee, H and Kwak, MH and Park, MC and Park, S and Wu, G and Lee, BL and Lee, Y and Kwon, HJ},
title = {CpG-DNA exerts antibacterial effects by protecting immune cells and producing bacteria-reactive antibodies.},
journal = {Scientific reports},
volume = {8},
number = {1},
pages = {16236},
doi = {10.1038/s41598-018-34722-y},
pmid = {30390012},
issn = {2045-2322},
support = {2016M3A9B6916708//National Research Foundation of Korea (NRF)/ ; 2017R1A2B2007373//National Research Foundation of Korea (NRF)/ ; },
abstract = {CpG-DNA activates various immune cells, contributing to the host defense against bacteria. Here, we examined the biological function of CpG-DNA in the production of bacteria-reactive antibodies. The administration of CpG-DNA increased survival in mice following infection with methicillin-resistant S. aureus and protected immune cell populations in the peritoneal cavity, bone marrow, and spleen. CpG-DNA injection likewise increased bacteria-reactive antibodies in the mouse peritoneal fluid and serum, which was dependent on TLR9. B cells isolated from the peritoneal cavity produced bacteria-reactive antibodies in vitro following CpG-DNA administration that enhanced the phagocytic activity of the peritoneal cells. The bacteria-reactive monoclonal antibody enhanced phagocytosis in vitro and protected mice after S. aureus infection. Therefore, we suggest that CpG-DNA enhances the antibacterial activity of the immune system by protecting immune cells and triggering the production of bacteria-reactive antibodies. Consequently, we believe that monoclonal antibodies could aid in the treatment of antibiotic-resistant bacterial infections.},
}
@article {pmid30388125,
year = {2018},
author = {Apremont, V and Cambon-Bonavita, MA and Cueff-Gauchard, V and François, D and Pradillon, F and Corbari, L and Zbinden, M},
title = {Gill chamber and gut microbial communities of the hydrothermal shrimp Rimicaris chacei Williams and Rona 1986: A possible symbiosis.},
journal = {PloS one},
volume = {13},
number = {11},
pages = {e0206084},
doi = {10.1371/journal.pone.0206084},
pmid = {30388125},
issn = {1932-6203},
abstract = {Rimicaris chacei Williams and Rona 1986, formerly named as Chorocaris chacei, is a caridean shrimp living in deep-sea hydrothermal ecosystems. This shrimp is endemic to the Mid Atlantic Ridge (MAR) and lives at the periphery of aggregates of its well-known congeneric R. exoculata Williams and Rona 1986. Contrasting with the very dense and mobile clusters formed by R. exoculata, R. chacei lives in small groups of several individuals that are not very mobile. Although devoid of the characteristic hypertrophied cephalothorax of R. exoculata, which harbors the ectosymbionts, a microbial community has also been reported in the cephalothorax of R. chacei. Previous data on morphology, behavior and isotopic values indicate a diet based on a combination of feeding on its epibiotic bacteria and scavenging or occasional predation. In this study, our objective was to describe, for the first time, the distribution, morphology and phylogeny of the microbial communities associated with R. chacei. This species is significantly less studied than R. exoculata, but nevertheless represents the only other known example of symbiosis in crustaceans of MAR hydrothermal vent sites. Microbial communities have been observed at the same locations as in R. exoculata (mouthparts, branchiostegites and digestive tract). However, in R. chacei, the surfaces occupied by the bacteria are smaller. The main lineages are affiliated to Epsilon and Gammaproteobacteria in the cephalothorax and to Deferribacteres, Mollicutes, Epsilon and Gammaproteobacteria in the digestive tract. Comparison with the well-described bacterial communities of R. exoculata and hypotheses about the role of these communities in R. chacei are discussed.},
}
@article {pmid30386575,
year = {2018},
author = {Kreisinger, J and Schmiedová, L and Petrželková, A and Tomášek, O and Adámková, M and Michálková, R and Martin, JF and Albrecht, T},
title = {Fecal microbiota associated with phytohaemagglutinin-induced immune response in nestlings of a passerine bird.},
journal = {Ecology and evolution},
volume = {8},
number = {19},
pages = {9793-9802},
doi = {10.1002/ece3.4454},
pmid = {30386575},
issn = {2045-7758},
abstract = {The vertebrate gastrointestinal tract is inhabited by a diverse community of bacteria, the so-called gut microbiota (GM). Research on captive mammalian models has revealed tight mutual interactions between immune functions and GM. However, our knowledge of GM versus immune system interactions in wild populations and nonmammalian species remains poor. Here, we focus on the association between GM community structure and immune response measured via the phytohaemagglutinin (PHA) skin swelling test in 12-day-old nestlings of a passerine bird, the barn swallow (Hirundo rustica). The PHA test, a widely used method in field ecoimmunology, assesses cell-mediated immunity. GM structure was inferred based on high-throughput 16S rRNA sequencing of microbial communities in fecal samples. We did not find any association between PHA response and GM diversity; however, our data revealed that the intensity of PHA response was correlated with differences in GM composition at the whole-community level. Ten bacterial operational taxonomic units corresponding to both putative commensal and pathogens were identified as drivers of the compositional variation. In conclusion, our study suggests existence of GM versus immune system interactions in a free-living nonmammalian species, which corresponds with previous research on captive vertebrates.},
}
@article {pmid30386564,
year = {2018},
author = {Piculell, BJ and Eckhardt, LG and Hoeksema, JD},
title = {Genetically determined fungal pathogen tolerance and soil variation influence ectomycorrhizal traits of loblolly pine.},
journal = {Ecology and evolution},
volume = {8},
number = {19},
pages = {9646-9656},
doi = {10.1002/ece3.4355},
pmid = {30386564},
issn = {2045-7758},
abstract = {Selection on genetically correlated traits within species can create indirect effects on one trait by selection on another. The consequences of these trait correlations are of interest because they may influence how suites of traits within species evolve under differing selection pressures, both natural and artificial. By utilizing genetic families of loblolly pine either tolerant (t) or susceptible (s) to two different suites of pathogenic fungi responsible for causing either pine decline or fusiform rust disease, we investigated trait variation and trait correlations within loblolly pine (Pinus taeda L.) by determining how ectomycorrhizal (EM) colonization relates to pathogen susceptibility. We detected interactions between susceptibility to pathogenic fungi and soil inoculation source on loblolly pine compatibility with the EM fungi Thelephora, and on relative growth rate of loblolly pine. Additionally, we detected spatial variation in the loblolly pine-EM fungi interaction, and found that variation in colonization rates by some members of the EM community is not dictated by genetic variation in the host plant but rather soil inoculation source alone. The work presented here illustrates the potential for indirect selection on compatibility with symbiotic EM fungi as a result of selection for resistance to fungal pathogens. Additionally, we present evidence that the host plant does not have a single &quot;mycorrhizal trait&quot; governing interactions with all EM fungi, but rather that it can interact with different fungal taxa independently. Synthesis. An understanding of the genetic architecture of essential traits in focal species is crucial if we are to anticipate and manage the results of natural and artificial selection. As demonstrated here, an essential but often overlooked symbiosis (that between plants and mycorrhizal fungi) may be indirectly influenced by directed selection on the host plant.},
}
@article {pmid30386154,
year = {2018},
author = {Conradi, M and Bandera, E and Mudrova, SV and Viatcheslav N Ivanenko, },
title = {Five new coexisting species of copepod crustaceans of the genus Spaniomolgus (Poecilostomatoida: Rhynchomolgidae), symbionts of the stony coral Stylophorapistillata (Scleractinia).},
journal = {ZooKeys},
volume = {},
number = {791},
pages = {71-95},
doi = {10.3897/zookeys.791.28775},
pmid = {30386154},
issn = {1313-2989},
abstract = {Spaniomolgus is a symbiotic genus of copepods of the poecilostomatoid family Rhynchomolgidae and is known to be associated with shallow-water reef-building hermatypic corals. Three species of this genus were previously found only in washings of Acropora and Stylophora in northern Madagascar. Four coral morphotypes of Stylophorapistillata (Pocilloporidae) were collected by SCUBA at 1 to 28 m depth in five sites in the Saudi Arabian Red Sea in 2013. Copepods found on these colonies were studied using light, confocal and scanning electron microscopy. Five new, and one known, species of the genus Spaniomolgus were discovered in washings and inside the galls of the hermatypic coral S.pistillata. The description of these new species (Spaniomolgusglobussp. n., S.stylophorussp. n., S.dentatussp. n., S.maculatussp. n., and S.acutussp. n.) and a key for the identification of all of its congeners is provided herein.},
}
@article {pmid30385579,
year = {2018},
author = {Tso, GHW and Reales-Calderon, JA and Tan, ASM and Sem, X and Le, GTT and Tan, TG and Lai, GC and Srinivasan, KG and Yurieva, M and Liao, W and Poidinger, M and Zolezzi, F and Rancati, G and Pavelka, N},
title = {Experimental evolution of a fungal pathogen into a gut symbiont.},
journal = {Science (New York, N.Y.)},
volume = {362},
number = {6414},
pages = {589-595},
doi = {10.1126/science.aat0537},
pmid = {30385579},
issn = {1095-9203},
abstract = {Gut microbes live in symbiosis with their hosts, but how mutualistic animal-microbe interactions emerge is not understood. By adaptively evolving the opportunistic fungal pathogen Candida albicans in the mouse gastrointestinal tract, we selected strains that not only had lost their main virulence program but also protected their new hosts against a variety of systemic infections. This protection was independent of adaptive immunity, arose as early as a single day postpriming, was dependent on increased innate cytokine responses, and was thus reminiscent of &quot;trained immunity.&quot; Because both the microbe and its new host gain some advantages from their interaction, this experimental system might allow direct study of the evolutionary forces that govern the emergence of mutualism between a mammal and a fungus.},
}
@article {pmid30384912,
year = {2018},
author = {Ankati, S and Rani, TS and Podile, AR},
title = {Partner-triggered proteome changes in the cell wall of Bacillus sonorensis and roots of groundnut benefit each other.},
journal = {Microbiological research},
volume = {217},
number = {},
pages = {91-100},
doi = {10.1016/j.micres.2018.10.003},
pmid = {30384912},
issn = {1618-0623},
abstract = {Plant growth promoting rhizobacteria (PGPR) promote plant growth and activate defense response against phytopathogens. At the subcellular level plant-PGPR interaction is less understood, which would be essential for future improvement(s) of PGPR formulations. In a rigorous screening process, that also involved efficient PGPR strains, Bacillus sonorensis RS4 was selected to study partner-triggered interactions. The potential of B. sonorensis RS4 to improve growth of groundnut, efficiency to colonize roots, and influence on root topology was assessed. Twenty four cell wall proteins of B. sonorensis RS4 [in presence of groundnut root exudates (REs)], and 22 groundnut root proteins (in RS4-bacterized plants) were differentially expressed. The alterations in cell wall proteins of B. sonorensis RS4 were primarily related to the amino acids synthesis, chemotaxis, antioxidant-metabolism, carbohydrate metabolism, transporters, and antibiosis-related secondary metabolites. Root proteins that were differentially expressed during the interaction may be involved in plant growth, defense responses, and in transportation. The changes in B. sonorensis RS4 cell wall proteome and groundnut root proteome, suggest that at least a part of the proteome changes triggered by each of the partners appear to play a significant role in helping each other akin to symbiosis.},
}
@article {pmid30384840,
year = {2018},
author = {Ying, H and Cooke, I and Sprungala, S and Wang, W and Hayward, DC and Tang, Y and Huttley, G and Ball, EE and Forêt, S and Miller, DJ},
title = {Comparative genomics reveals the distinct evolutionary trajectories of the robust and complex coral lineages.},
journal = {Genome biology},
volume = {19},
number = {1},
pages = {175},
doi = {10.1186/s13059-018-1552-8},
pmid = {30384840},
issn = {1474-760X},
abstract = {BACKGROUND: Despite the biological and economic significance of scleractinian reef-building corals, the lack of large molecular datasets for a representative range of species limits understanding of many aspects of their biology. Within the Scleractinia, based on molecular evidence, it is generally recognised that there are two major clades, Complexa and Robusta, but the genomic bases of significant differences between them remain unclear.<br><br>RESULTS: Draft genome assemblies and annotations were generated for three coral species: Galaxea fascicularis (Complexa), Fungia sp., and Goniastrea aspera (Robusta). Whilst phylogenetic analyses strongly support a deep split between Complexa and Robusta, synteny analyses reveal a high level of gene order conservation between all corals, but not between corals and sea anemones or between sea anemones. HOX-related gene clusters are, however, well preserved across all of these combinations. Differences between species are apparent in the distribution and numbers of protein domains and an apparent correlation between number of HSP20 proteins and stress tolerance. Uniquely amongst animals, a complete histidine biosynthesis pathway is present in robust corals but not in complex corals or sea anemones. This pathway appears to be ancestral, and its retention in the robust coral lineage has important implications for coral nutrition and symbiosis.<br><br>CONCLUSIONS: The availability of three new coral genomes enabled recognition of a de novo histidine biosynthesis pathway in robust corals which is only the second identified biosynthetic difference between corals. These datasets provide a platform for understanding many aspects of coral biology, particularly the interactions of corals with their endosymbionts.},
}
@article {pmid30383392,
year = {2018},
author = {Parasyri, A and Papazi, A and Stamatis, N and Zerveas, S and Avramidou, EV and Doulis, AG and Pirintsos, S and Kotzabasis, K},
title = {Lichen as Micro-Ecosystem: Extremophilic Behavior with Astrobiotechnological Applications.},
journal = {Astrobiology},
volume = {18},
number = {12},
pages = {1528-1542},
doi = {10.1089/ast.2017.1789},
pmid = {30383392},
issn = {1557-8070},
abstract = {This work demonstrates the tolerance of lichen Pleurosticta acetabulum under extreme conditions similar to those encountered in extraterrestrial environments. Specifically, the impact of three extreme Mars-like conditions-complete dehydration, extremely low temperature (-196°C/77K), and oxygen depletion-on lichens was investigated. The symbiosis of mycobiont and photobiont partners creates a micro-ecosystem that ensures viability of both symbiotic partners under prolonged desiccation and extremely low temperatures without any cultivation care. Changes in the molecular structure and function of the photosynthetic apparatus, in the level of chlorophylls, polyamines, fatty acids, carbohydrates, ergosterol, efflux of K+, and DNA methylation ensure the ecological integrity of the system and offer resistance of lichens to above-mentioned extreme environmental conditions. For the first time, we also demonstrate that the unprecedented polyextremophilic characteristic of lichens could be linked to biotechnological applications, following exposure to these extreme conditions, such that their ability to produce a high yield of hydrogen was unchanged. All these support that lichens are (a) ideal model systems for a space mission to inhabit other planets, supporting also the aspect that the panspermia theory could be extended to incorporate in the traveling entities not only single organisms but micro-ecosystems like lichens, and (b) ideal model systems for astrobiotechnological applications (hydrogen production), such as in the development of bioregeneration systems for extraterrestrial environments.},
}
@article {pmid30382153,
year = {2018},
author = {Cunning, R and Bay, RA and Gillette, P and Baker, AC and Traylor-Knowles, N},
title = {Comparative analysis of the Pocillopora damicornis genome highlights role of immune system in coral evolution.},
journal = {Scientific reports},
volume = {8},
number = {1},
pages = {16134},
doi = {10.1038/s41598-018-34459-8},
pmid = {30382153},
issn = {2045-2322},
support = {OCE-1358699//National Science Foundation (NSF)/ ; OCE-1358699//National Science Foundation (NSF)/ ; },
abstract = {Comparative analysis of the expanding genomic resources for scleractinian corals may provide insights into the evolution of these organisms, with implications for their continued persistence under global climate change. Here, we sequenced and annotated the genome of Pocillopora damicornis, one of the most abundant and widespread corals in the world. We compared this genome, based on protein-coding gene orthology, with other publicly available coral genomes (Cnidaria, Anthozoa, Scleractinia), as well as genomes from other anthozoan groups (Actiniaria, Corallimorpharia), and two basal metazoan outgroup phlya (Porifera, Ctenophora). We found that 46.6% of P. damicornis genes had orthologs in all other scleractinians, defining a coral 'core' genome enriched in basic housekeeping functions. Of these core genes, 3.7% were unique to scleractinians and were enriched in immune functionality, suggesting an important role of the immune system in coral evolution. Genes occurring only in P. damicornis were enriched in cellular signaling and stress response pathways, and we found similar immune-related gene family expansions in each coral species, indicating that immune system diversification may be a prominent feature of scleractinian coral evolution at multiple taxonomic levels. Diversification of the immune gene repertoire may underlie scleractinian adaptations to symbiosis, pathogen interactions, and environmental stress.},
}
@article {pmid30381385,
year = {2018},
author = {Russell, SL and McCartney, E and Cavanaugh, CM},
title = {Transmission strategies in a chemosynthetic symbiosis: detection and quantification of symbionts in host tissues and their environment.},
journal = {Proceedings. Biological sciences},
volume = {285},
number = {1890},
pages = {},
doi = {10.1098/rspb.2018.2157},
pmid = {30381385},
issn = {1471-2954},
abstract = {Transmission of bacteria vertically through host tissues ensures offspring acquire symbionts; however, horizontal transmission is an effective strategy for many associations and plays a role in some vertically transmitted symbioses. The bivalve Solemya velum and its gammaproteobacterial chemosynthetic symbionts exhibit evolutionary evidence of both transmission modes, but the dominant strategy on an ecological time scale is unknown. To address this, a specific primer set was developed and validated for the S. velum symbiont using a novel workflow called specific marker design (SMD). Symbionts were quantified in spawned eggs and sediment and seawater samples from S. velum habitats with qPCR. Each egg was estimated to contain 50-100 symbiont genomes. By contrast, symbiont DNA was found at low abundance/occurrence in sediment and seawater, often co-occurring with host mitochondrial DNA, obscuring its origin. To ascertain when eggs become infected, histological sections of S. velum tissues were labelled for symbiont 16S rRNA via in situ hybridization. This revealed symbionts in the ovary walls and mature oocytes, suggesting association in late oogenesis. These data support the hypothesis that S. velum symbionts are vertically transmitted every host generation, thus genetic signatures of horizontal transmission are driven by ecologically infrequent events. This knowledge furthers our understanding of vertical and horizontal mode integration and provides insights across animal-bacterial chemosynthetic symbioses.},
}
@article {pmid30378690,
year = {2018},
author = {Rey, T and André, O and Nars, A and Dumas, B and Gough, C and Bottin, A and Jacquet, C},
title = {Lipo-chitooligosaccharide signalling blocks a rapid pathogen-induced ROS burst without impeding immunity.},
journal = {The New phytologist},
volume = {},
number = {},
pages = {},
doi = {10.1111/nph.15574},
pmid = {30378690},
issn = {1469-8137},
support = {//Région Occitanie/ ; INEE 36//CNRS/ ; //Université Paul Sabatier/ ; //Ministère de l'Enseignement Supérieur et de la Recherche/ ; ANR-08-BLAN-0208-01//Agence Nationale de la Recherche/ ; ANR-10-GENM-0007//Agence Nationale de la Recherche/ ; ANR-14-CE18-0008-01//Agence Nationale de la Recherche/ ; ANR-10-LABX-41//'Laboratoire d'Excellence' (LABEX) entitled TULIP/ ; },
abstract = {Molecular signals released by microbes at the surface of plant roots and leaves largely determine host responses, notably by triggering either immunity or symbiosis. How these signalling pathways cross-talk upon coincident perception of pathogens and symbionts is poorly described in plants forming symbiosis. Nitrogen fixing symbiotic Rhizobia spp. and arbuscular mycorrhizal fungi produce lipo-chitooligosaccharides (LCOs) to initiate host symbiotic programmes. In Medicago truncatula roots, the perception of LCOs leads to reduced efflux of reactive oxygen species (ROS). By contrast, pathogen perception generally triggers a strong ROS burst and activates defence gene expression. Here we show that incubation of M. truncatula seedlings with culture filtrate (CF) of the legume pathogen Aphanomyces euteiches alone or simultaneously with Sinorhizobium meliloti LCOs, resulted in a strong ROS release. However, this response was completely inhibited if CF was added after pre-incubation of seedlings with LCOs. By contrast, expression of immunity-associated genes in response to CF and disease resistance to A. euteiches remained unaffected by LCO treatment of M. truncatula roots. Our findings suggest that symbiotic plants evolved ROS inhibition response to LCOs to facilitate early steps of symbiosis whilst maintaining a parallel defence mechanisms toward pathogens.},
}
@article {pmid30377970,
year = {2018},
author = {Loizia, P and Neofytou, N and Zorpas, AA},
title = {The concept of circular economy strategy in food waste management for the optimization of energy production through anaerobic digestion.},
journal = {Environmental science and pollution research international},
volume = {},
number = {},
pages = {},
doi = {10.1007/s11356-018-3519-4},
pmid = {30377970},
issn = {1614-7499},
abstract = {Food waste management (FWM) is considered to be an extremely important social issue besides an environmental one. Worldwide, it is estimated that 1.3 billion t/year of foods are disposed of in landfills (including edible and inedible foods). Moreover, FAO indicated that if food waste (FW) was a country, it could be the 3rd biggest CO2 producer after China and the USA with more than 3.5-4.2 billion of t equivalence CO2. Each citizen in the entire EU produces approximately 179 kg/year FW equal more or less with 600 €/year. This paper focuses on the concept of circular economy (CE) and how can we optimize and improve the production of biogas from UASB-R (upflow anaerobic sludge blanket reactor) using FW and natural minerals (clinoptilolite). The study was elaborated through laboratory scale experiments using different mixtures of FW, liquid waste from slaughterhouse (LWS), and natural clinoptilolite (Cli). The amount of biogas produced and the methane content of biogas were used as indicators in order to monitor and asses the performance of the anaerobic digester. The results of the present study were encouraging towards the use of FW in existing anaerobic treatment plants, suggesting selective collection at source of FW, diversion from landfills, and use as a secondary resource for energy recovery through a transition to a CE. The results indicate that the use of FW with zeolite duplicates the production of CH4 within the same days of production compared with the control sample.},
}
@article {pmid30372538,
year = {2018},
author = {Correia, M and Heleno, R and da Silva, LP and Costa, JM and Rodríguez-Echeverría, S},
title = {First evidence for the joint dispersal of mycorrhizal fungi and plant diaspores by birds.},
journal = {The New phytologist},
volume = {},
number = {},
pages = {},
doi = {10.1111/nph.15571},
pmid = {30372538},
issn = {1469-8137},
abstract = {Seed dispersal allows plants to colonize new sites and escape from pathogens and intraspecific competition, maintaining plant genetic diversity and regulating plant distribution. Conversely, most plant species form mutualistic associations with arbuscular mycorrhizal (AM) fungi in a symbiosis established right after seed germination. Since AM fungi are obligate symbionts, using the same dispersal vector as their host should be highly advantageous for their survival, however, the co-dispersal of seeds and AM fungal spores has never been confirmed. We aim to clarify the potential role of European birds, essential dispersers for many plant species, as co-dispersers of seeds and AM fungal spores. To achieve that, 63 bird droppings with intact seeds were placed in sterilized soil and maintained for 4 months in a protected environment to avoid contamination. Additionally, 173 bird droppings and 729 gauze swabs used to clean birds' feet were inspected for AM fungal spores. Although no spores were detected by direct observation of these samples, seven Rubus ulmifolius seedlings obtained from four independent droppings of Erithacus rubecula and Sylvia melanocephala were colonized by AM fungi. Our results show that birds can effectively co-disperse viable seeds and AM fungal spores, potentially over long distances, providing a pivotal mechanism to understand the cosmopolitan distribution of AM fungi. This article is protected by copyright. All rights reserved.},
}
@article {pmid30371901,
year = {2018},
author = {Korhonen, A and Lehto, T and Heinonen, J and Repo, T},
title = {Whole-plant frost hardiness of mycorrhizal (Hebeloma sp. or Suillus luteus) and non-mycorrhizal Scots pine seedlings.},
journal = {Tree physiology},
volume = {},
number = {},
pages = {},
doi = {10.1093/treephys/tpy105},
pmid = {30371901},
issn = {1758-4469},
abstract = {Ectomycorrhizal trees are common in the cold regions of the world, yet the role of the mycorrhizal symbiosis in plant cold tolerance is poorly known. Moreover, the standard methods for testing plant frost hardiness may not be adequate for roots and mycorrhizas. The aims of this study were to compare the frost hardiness of mycorrhizal and non-mycorrhizal Scots pine (Pinus sylvestris L.) seedlings and to test the use of reverse-flow root hydraulic conductance (Kr) measurement for root frost hardiness determination. Mycorrhizal (Hebeloma sp. or Suillus luteus) and non-mycorrhizal seedlings were grown in controlled-environment chambers for 13 weeks. After this, half of the plants were allotted to a non-hardening treatment (long day and high temperature, same as during the preceding growing season) and the other half to a hardening (short day and low temperature) 'autumn' treatment for 4 weeks. The intact seedlings were exposed to whole-plant freezing tests and the needle frost hardiness was measured by relative electrolyte leakage (REL) method. The seedlings were grown for three more weeks for visual damage assessment and Kr measurements using a high-pressure flow meter (HPFM). Mycorrhizas did not affect the frost hardiness of seedlings in either hardening treatment. The effect of the hardening treatment on frost hardiness was shown by REL and visual assessment of the aboveground parts as well as Kr of roots. Non-mycorrhizal plants were larger than mycorrhizal ones while nitrogen and phosphorus contents (per unit dry mass) were similar in all mycorrhiza treatments. In plants with no frost exposure, the non-mycorrhizal treatment had higher Kr. There was no mycorrhizal effect on plant frost hardiness when nutritional effects were excluded. Further studies are needed on the role of mycorrhizas especially in the recovery of growth and nutrient uptake in cold soils in the spring. The HPFM is useful novel method for assessment of root damage.},
}
@article {pmid30367543,
year = {2018},
author = {Alcaraz, JP and Cinquin, P and Martin, DK},
title = {Tackling the Concept of Symbiotic Implantable Medical Devices with Nanobiotechnologies.},
journal = {Biotechnology journal},
volume = {},
number = {},
pages = {},
doi = {10.1002/biot.201800102},
pmid = {30367543},
issn = {1860-7314},
support = {ANR-15-CE05-003-01//Agence Nationale de la Recherche/ ; },
abstract = {This review takes an approach to implanted medical devices that considers whether the intention of the implanted device is to have any communication of energy or materials with the body. The first part describes some specific examples of three different classes of implants, analyzed with regards to the type of signal sent to cells. Through several examples, the authors describe that a one way signaling to the body leads to encapsulation or degradation. In most cases, those phenomena do not lead to major problems. However, encapsulation or degradation are critical for new kinds of medical devices capable of duplex communication, which are defined in this review as symbiotic devices. The concept the authors propose is that implanted medical devices that need to be symbiotic with the body also need to be designed with an intended duplex communication of energy and materials with the body. This extends the definition of a biocompatible system to one that requires stable exchange of materials between the implanted device and the body. Having this novel concept in mind will guide research in a new field between medical implant and regenerative medicine to create actual symbiotic devices.},
}
@article {pmid30365488,
year = {2018},
author = {Tan, WH and Reyes, ML and Hoang, KL and Acevedo, T and Leon, F and Barbosa, JD and Gerardo, NM},
title = {How symbiosis and ecological context influence the variable expression of transgenerational wing induction upon fungal infection of aphids.},
journal = {PloS one},
volume = {13},
number = {10},
pages = {e0201865},
doi = {10.1371/journal.pone.0201865},
pmid = {30365488},
issn = {1932-6203},
abstract = {Aphids, like most animals, mount a diverse set of defenses against pathogens. For aphids, two of the best studied defenses are symbiont-conferred protection and transgenerational wing induction. Aphids can harbor bacterial symbionts that provide protection against pathogens, parasitoids and predators, as well as against other environmental stressors. In response to signals of danger, aphids also protect not themselves but their offspring by producing more winged than unwinged offspring as a way to ensure that their progeny may be able to escape deteriorating conditions. Such transgenerational wing induction has been studied most commonly as a response to overcrowding of host plants and presence of predators, but recent evidence suggests that pea aphids (Acyrthosiphon pisum) may also begin to produce a greater proportion of winged offspring when infected with fungal pathogens. Here, we explore this phenomenon further by asking how protective symbionts, pathogen dosage and environmental conditions influence this response. Overall, while we find some evidence that protective symbionts can modulate transgenerational wing induction in response to fungal pathogens, we observe that transgenerational wing induction in response to fungal infection is highly variable. That variability cannot be explained entirely by symbiont association, by pathogen load or by environmental stress, leaving the possibility that a complex interplay of genotypic and environmental factors may together influence this trait.},
}
@article {pmid30364181,
year = {2018},
author = {Becana, M and Wienkoop, S and Matamoros, MA},
title = {Sulfur Transport and Metabolism in Legume Root Nodules.},
journal = {Frontiers in plant science},
volume = {9},
number = {},
pages = {1434},
doi = {10.3389/fpls.2018.01434},
pmid = {30364181},
issn = {1664-462X},
abstract = {Sulfur is an essential nutrient in plants as a constituent element of some amino acids, metal cofactors, coenzymes, and secondary metabolites. Not surprisingly, sulfur deficiency decreases plant growth, photosynthesis, and seed yield in both legumes and non-legumes. In nodulated legumes, sulfur supply is positively linked to symbiotic nitrogen fixation (SNF) and sulfur starvation causes three additional major effects: decrease of nodulation, inhibition of SNF, and slowing down of nodule metabolism. These effects are due, at least in part, to the impairment of nitrogenase biosynthesis and activity, the accumulation of nitrogen-rich amino acids, and the decline in leghemoglobin, ferredoxin, ATP, and glucose in nodules. During the last decade, some major advances have been made about the uptake and metabolism of sulfur in nodules. These include the identification of the sulfate transporter SST1 in the symbiosomal membrane, the finding that glutathione produced in the bacteroids and host cells is essential for nodule activity, and the demonstration that sulfur assimilation in the whole plant is reprogrammed during symbiosis. However, many crucial questions still remain and some examples follow. In the first place, it is of paramount importance to elucidate the mechanism by which sulfur deficiency limits SNF. It is unknown why homoglutahione replaces glutathione as a major water-soluble antioxidant, redox buffer, and sulfur reservoir, among other relevant functions, only in certain legumes and also in different tissues of the same legume species. Much more work is required to identify oxidative post-translational modifications entailing cysteine and methionine residues and to determine how these modifications affect protein function and metabolism in nodules. Likewise, most interactions of antioxidant metabolites and enzymes bearing redox-active sulfur with transcription factors need to be defined. Solving these questions will pave the way to decipher sulfur-dependent mechanisms that regulate SNF, thereby gaining a deep insight into how nodulated legumes adapt to the fluctuating availability of nutrients in the soil.},
}
@article {pmid30364174,
year = {2018},
author = {Gifford, I and Battenberg, K and Vaniya, A and Wilson, A and Tian, L and Fiehn, O and Berry, AM},
title = {Distinctive Patterns of Flavonoid Biosynthesis in Roots and Nodules of Datisca glomerata and Medicago spp. Revealed by Metabolomic and Gene Expression Profiles.},
journal = {Frontiers in plant science},
volume = {9},
number = {},
pages = {1463},
doi = {10.3389/fpls.2018.01463},
pmid = {30364174},
issn = {1664-462X},
support = {U24 DK097154/DK/NIDDK NIH HHS/United States ; U2C ES030158/ES/NIEHS NIH HHS/United States ; },
abstract = {Plants within the Nitrogen-fixing Clade (NFC) of Angiosperms form root nodule symbioses with nitrogen-fixing bacteria. Actinorhizal plants (in Cucurbitales, Fagales, Rosales) form symbioses with the actinobacteria Frankia while legumes (Fabales) form symbioses with proteobacterial rhizobia. Flavonoids, secondary metabolites of the phenylpropanoid pathway, have been shown to play major roles in legume root nodule symbioses: as signal molecules that in turn trigger rhizobial nodulation initiation signals and acting as polar auxin transport inhibitors, enabling a key step in nodule organogenesis. To explore a potentially broader role for flavonoids in root nodule symbioses across the NFC, we combined metabolomic and transcriptomic analyses of roots and nodules of the actinorhizal host Datisca glomerata and legumes of the genus Medicago. Patterns of biosynthetic pathways were inferred from flavonoid metabolite profiles and phenylpropanoid gene expression patterns in the two hosts to identify similarities and differences. Similar classes of flavonoids were represented in both hosts, and an increase in flavonoids generally in the nodules was observed, with differences in flavonoids prominent in each host. While both hosts produced derivatives of naringenin, the metabolite profile in D. glomerata indicated an emphasis on the pinocembrin biosynthetic pathway, and an abundance of flavonols with potential roles in symbiosis. Additionally, the gene expression profile indicated a decrease in expression in the lignin/monolignol pathway. In Medicago sativa, by contrast, isoflavonoids were highly abundant featuring more diverse and derived isoflavonoids than D. glomerata. Gene expression patterns supported these differences in metabolic pathways, especially evident in a difference in expression of cinnamic acid 4-hydroxylase (C4H), which was expressed at substantially lower levels in D. glomerata than in a Medicago truncatula transcriptome where it was highly expressed. C4H is a major rate-limiting step in phenylpropanoid biosynthesis that separates the pinocembrin pathway from the lignin/monolignol and naringenin-based flavonoid branches. Shikimate O-hydroxycinnamoyltransferase, the link between flavonoid biosynthesis and the lignin/monolignol pathway, was also expressed at much lower levels in D. glomerata than in M. truncatula. Our results indicate (a) a likely major role for flavonoids in actinorhizal nodules, and (b) differences in metabolic flux in flavonoid and phenylpropanoid biosynthesis between the different hosts in symbiosis.},
}
@article {pmid30363063,
year = {2018},
author = {Antonets, KS and Onishchuk, OP and Kurchak, ON and Volkov, KV and Lykholay, AN and Andreeva, EA and Andronov, EE and Pinaev, AG and Provorov, NA and Nizhnikov, AA},
title = {[Proteomic Profile of the Bacterium Sinorhizobium meliloti Depends on Its Life Form and Host Plant Species].},
journal = {Molekuliarnaia biologiia},
volume = {52},
number = {5},
pages = {898-904},
doi = {10.1134/S0026898418050038},
pmid = {30363063},
issn = {0026-8984},
abstract = {The importance of root nodule bacteria in biotechnology is determined by their distinctive feature: symbiotic nitrogen fixation resulting in the production of organic nitrogen-containing compounds. While interacting with host legume plants, the cells of these bacteria undergo global changes at all levels of expression of genetic information leading to the formation in root nodules of so-called bacteroids functioning as nitrogen fixation factories. The molecular mechanisms underlying plant-microbial symbiosis are actively investigated, and one of the most interesting and poorly studied aspects of this problem is the species-specificity of interaction between root nodule bacteria and host plants. In this work we have performed the proteomic analysis of the Sinorhizobium meliloti bacteroids isolated from two legume species: alfalfa (Medicago sativa L.) and yellow sweet clover (Melilotus officinalis L.). It has been shown that the S. meliloti bacteroids produce a lot of proteins (many of them associated with symbiosis) in a host-specific manner, i.e., only in certain host plant species. It has been demonstrated for the first time that the levels of expression in bacteroids of the genes encoding the ExoZ and MscL proteins responsible for the synthesis of surface lipopolysaccha-rides and formation of a large conductance mechanosensitive channel, respectively, depend on a host plant species that confirms the results of proteomic analysis. Overall, our data show that the regulation of bacteroid development by the host plant has species-specific features.},
}
@article {pmid30358444,
year = {2018},
author = {Miyokawa, R and Tsuda, T and Kanaya, HJ and Kusumi, J and Tachida, H and Kobayakawa, Y},
title = {Horizontal Transmission of Symbiotic Green Algae Between Hydra Strains.},
journal = {The Biological bulletin},
volume = {235},
number = {2},
pages = {113-122},
doi = {10.1086/699705},
pmid = {30358444},
issn = {1939-8697},
abstract = {Some hydra strains belonging to the vulgaris group show a symbiotic relationship with green algae Chlorococcum sp. The symbiotic green algae can escape from the host polyps and can form swimming zoospores (which have two flagella) in culture solution. We observed that co-culture with the symbiotic polyps caused horizontal transmission of the symbionts into some non-symbiotic hydra strains that have no symbionts in nature and that belong not only to the vulgaris group but also to other hydra species groups. Although most of the horizontal transmission has ended in transient symbioses, a newly formed symbiosis between the symbiotic Chlorococcum sp. and strain 105 of Hydra vulgaris (Hydra magnipapillata) has been sustained for more than five years and has caused morphological and behavioral changes in the host polyps. We named this strain 105G. The asexual proliferation rate by budding increased under light conditions, although the feeding activity decreased and the polyp size was reduced in strain 105G. This new symbiosis between Chlorococcum sp. and strain 105G of H. vulgaris provides us with an intriguing research system for investigating the origin of symbiosis.},
}
@article {pmid30358047,
year = {2018},
author = {Gabaldón, T},
title = {Relative timing of mitochondrial endosymbiosis and the &quot;pre-mitochondrial symbioses&quot; hypothesis.},
journal = {IUBMB life},
volume = {70},
number = {12},
pages = {1188-1196},
doi = {10.1002/iub.1950},
pmid = {30358047},
issn = {1521-6551},
support = {ERC-2016-724173//H2020 European Research Council/ ; H2020-MSCA-ITN-2014-642095//H2020 Marie Skłodowska-Curie Actions/ ; BFU2015-67107//Secretaría de Estado de Investigación, Desarrollo e Innovación/ ; H2020-MSCA-ITN-2014-642095//Marie Sklodowska-Curie/ ; ERC-2016-724173//European Union's Horizon 2020/ ; SGR857//Catalan Research Agency/ ; //CERCA Programme/Generalitat de Catalunya/ ; //European Regional Development Fund/ ; BFU2015-67107//Spanish Ministry of Economy, Industry, and Competitiveness/ ; SEV-2012-0208//Spanish Ministry of Economy, Industry, and Competitiveness/ ; },
abstract = {The origin of eukaryotes stands as a major open question in biology. Central to this question is the nature and timing of the origin of the mitochondrion, an ubiquitous eukaryotic organelle originated by the endosymbiosis of an alphaproteobacterial ancestor. Different hypotheses disagree, among other aspects, on whether mitochondria were acquired early or late during eukaryogenesis. Similarly, the nature and complexity of the receiving host is debated, with models ranging from a simple prokaryotic host to an already complex proto-eukaryote. Here, I will discuss recent findings from phylogenomics analyses of extant genomes that are shedding light into the evolutionary origins of the eukaryotic ancestor, and which suggest a later acquisition of alpha-proteobacterial derived proteins as compared to those with different bacterial ancestries. I argue that simple eukaryogenesis models that assume a binary symbiosis between an archaeon host and an alpha-proteobacterial proto-mitochondrion cannot explain the complex chimeric nature that is inferred for the eukaryotic ancestor. To reconcile existing hypotheses with the new data, I propose the &quot;pre-mitochondrial symbioses&quot; hypothesis that provides a framework for eukaryogenesis scenarios involving alternative symbiotic interactions that predate the acquisition of mitochondria. © 2018 The Authors. IUBMB Life published by Wiley Periodicals, Inc. on behalf of International Union of Biochemistry and Molecular Biology, 70(12):1188-1196, 2018.},
}
@article {pmid30356788,
year = {2018},
author = {Prazeres, M},
title = {Bleaching-Associated Changes in the Microbiome of Large Benthic Foraminifera of the Great Barrier Reef, Australia.},
journal = {Frontiers in microbiology},
volume = {9},
number = {},
pages = {2404},
doi = {10.3389/fmicb.2018.02404},
pmid = {30356788},
issn = {1664-302X},
abstract = {Ocean warming is known to cause detrimental effects in coral reef fauna that rely on photo-symbiosis for survival. Microbial associations can facilitate the success of species across a range of environmental conditions, and play a role in the capacity of organisms to respond to climate change. In 2016, the Great Barrier Reef experienced its third mass bleaching event, with sea surface temperature rising to 1.3°C above long-term monthly summer averages. Here, I investigate the effects of ocean warming on the chlorophyll a (chl a) content and microbiome of the large benthic Foraminifera Amphistegina radiata. Samples were collected in January and April 2016, before and after the mass bleaching event. In total, 71 specimens were collected from two different depths (6- and 18-m) to investigate depth-dependant responses associated with changes in chl a and microbiome. Pigment analysis showed a significant reduction in chl a between time points in specimens collected at both depths. Reduction in pigmentation was accompanied by changes in the microbiome, and a significant interaction of depth and time was observed. Genus-level bacterial community associated with A. radiata was significantly different across depth and time. However, ocean warming affected populations at both depths to a similar extent, and resulted in change from a Betaproteobacteria-dominated assemblage in January to a more diverse bacterial community by April. Analysis of presence/absence and relative abundance of bacterial taxa revealed significant differences between time points at both depths analyzed. OTUs classified as Firmicutes, which were either absent, or present in very low relative abundances (<0.1%) across all sample groups in January, were identified in abundances as high as ∼20% in specimens collected from 18-m depth in April. Class-level shifts were observed in shallow-dwelling specimens, from high abundances of Betaproteobacteria to a high abundance and diversity of Actinobacteria. These results demonstrate the sensitivity of LBF to the effects of ocean warming, for which depth did not provide protection, and highlights the capacity of LBF to re-assemble bacterial communities after a disturbance. This study provides the first molecular-based demonstration of changes in foraminifera-associated bacterial assemblages during a bleaching event on a natural reef system.},
}
@article {pmid30356724,
year = {2018},
author = {Volpe, V and Chitarra, W and Cascone, P and Volpe, MG and Bartolini, P and Moneti, G and Pieraccini, G and Di Serio, C and Maserti, B and Guerrieri, E and Balestrini, R},
title = {The Association With Two Different Arbuscular Mycorrhizal Fungi Differently Affects Water Stress Tolerance in Tomato.},
journal = {Frontiers in plant science},
volume = {9},
number = {},
pages = {1480},
doi = {10.3389/fpls.2018.01480},
pmid = {30356724},
issn = {1664-462X},
abstract = {Arbuscular mycorrhizal (AM) fungi are very widespread, forming symbiotic associations with ∼80% of land plant species, including almost all crop plants. These fungi are considered of great interest for their use as biofertilizer in low-input and organic agriculture. In addition to an improvement in plant nutrition, AM fungi have been reported to enhance plant tolerance to important abiotic and biotic environmental conditions, especially to a reduced availability of resources. These features, to be exploited and applied in the field, require a thorough identification of mechanisms involved in nutrient transfer, metabolic pathways induced by single and multiple stresses, physiological and eco-physiological mechanisms resulting in improved tolerance. However, cooperation between host plants and AM fungi is often related to the specificity of symbiotic partners, the environmental conditions and the availability of resources. In this study, the impact of two AM fungal species (Funneliformis mosseae and Rhizophagus intraradices) on the water stress tolerance of a commercial tomato cultivar (San Marzano nano) has been evaluated in pots. Biometric and eco-physiological parameters have been recorded and gene expression analyses in tomato roots have been focused on plant and fungal genes involved in inorganic phosphate (Pi) uptake and transport. R. intraradices, which resulted to be more efficient than F. mosseae to improve physiological performances, was selected to assess the role of AM symbiosis on tomato plants subjected to combined stresses (moderate water stress and aphid infestation) in controlled conditions. A positive effect on the tomato indirect defense toward aphids in terms of enhanced attraction of their natural enemies was observed, in agreement with the characterization of volatile organic compound (VOC) released. In conclusion, our results offer new insights for understanding the molecular and physiological mechanisms involved in the tolerance toward water deficit as mediated by a specific AM fungus. Moreover, they open new perspectives for the exploitation of AM symbiosis to enhance crop tolerance to abiotic and biotic stresses in a scenario of global change.},
}
@article {pmid30355664,
year = {2018},
author = {Epstein, B and Abou-Shanab, RAI and Shamseldin, A and Taylor, MR and Guhlin, J and Burghardt, LT and Nelson, M and Sadowsky, MJ and Tiffin, P},
title = {Genome-Wide Association Analyses in the Model Rhizobium Ensifer meliloti.},
journal = {mSphere},
volume = {3},
number = {5},
pages = {},
doi = {10.1128/mSphere.00386-18},
pmid = {30355664},
issn = {2379-5042},
abstract = {Genome-wide association studies (GWAS) can identify genetic variants responsible for naturally occurring and quantitative phenotypic variation. Association studies therefore provide a powerful complement to approaches that rely on de novo mutations for characterizing gene function. Although bacteria should be amenable to GWAS, few GWAS have been conducted on bacteria, and the extent to which nonindependence among genomic variants (e.g., linkage disequilibrium [LD]) and the genetic architecture of phenotypic traits will affect GWAS performance is unclear. We apply association analyses to identify candidate genes underlying variation in 20 biochemical, growth, and symbiotic phenotypes among 153 strains of Ensifer meliloti For 11 traits, we find genotype-phenotype associations that are stronger than expected by chance, with the candidates in relatively small linkage groups, indicating that LD does not preclude resolving association candidates to relatively small genomic regions. The significant candidates show an enrichment for nucleotide polymorphisms (SNPs) over gene presence-absence variation (PAV), and for five traits, candidates are enriched in large linkage groups, a possible signature of epistasis. Many of the variants most strongly associated with symbiosis phenotypes were in genes previously identified as being involved in nitrogen fixation or nodulation. For other traits, apparently strong associations were not stronger than the range of associations detected in permuted data. In sum, our data show that GWAS in bacteria may be a powerful tool for characterizing genetic architecture and identifying genes responsible for phenotypic variation. However, careful evaluation of candidates is necessary to avoid false signals of association.IMPORTANCE Genome-wide association analyses are a powerful approach for identifying gene function. These analyses are becoming commonplace in studies of humans, domesticated animals, and crop plants but have rarely been conducted in bacteria. We applied association analyses to 20 traits measured in Ensifer meliloti, an agriculturally and ecologically important bacterium because it fixes nitrogen when in symbiosis with leguminous plants. We identified candidate alleles and gene presence-absence variants underlying variation in symbiosis traits, antibiotic resistance, and use of various carbon sources; some of these candidates are in genes previously known to affect these traits whereas others were in genes that have not been well characterized. Our results point to the potential power of association analyses in bacteria, but also to the need to carefully evaluate the potential for false associations.},
}
@article {pmid30353039,
year = {2018},
author = {Bongrand, C and Ruby, EG},
title = {Achieving a multi-strain symbiosis: strain behavior and infection dynamics.},
journal = {The ISME journal},
volume = {},
number = {},
pages = {},
doi = {10.1038/s41396-018-0305-8},
pmid = {30353039},
issn = {1751-7370},
support = {R01 AI050661/AI/NIAID NIH HHS/United States ; GM099507//U.S. Department of Health &amp; Human Services | NIH | National Institute of General Medical Sciences (NIGMS)/ ; R01 GM099507/GM/NIGMS NIH HHS/United States ; R01 OD011024/OD/NIH HHS/United States ; AI050661//U.S. Department of Health &amp; Human Services | NIH | National Institute of Allergy and Infectious Diseases (NIAID)/ ; OD011024//U.S. Department of Health &amp; Human Services | NIH | NIH Office of the Director (OD)/ ; R37 AI050661/AI/NIAID NIH HHS/United States ; },
abstract = {Strain diversity, while now recognized as a key driver underlying partner dynamics in symbioses, is usually difficult to experimentally manipulate and image in hosts with complex microbiota. To address this problem, we have used the luminous marine bacterium Vibrio fischeri, which establishes a symbiosis within the crypts of the nascent light organ of the squid Euprymna scolopes. Competition assays in newly hatched juvenile squid have shown that symbiotic V. fischeri are either niche-sharing &quot;S strains&quot;, which share the light organ when co-inoculated with other S strains, or niche-dominant &quot;D strains&quot;, which are typically found alone in the light organ after a co-colonization. To understand this D strain advantage, we determined the minimum time that different V. fischeri strains needed to initiate colonization and used confocal microscopy to localize the symbionts along their infection track. Further, we determined whether symbiont-induced host morphogenic events also occurred earlier during a D strain colonization. We conclude that D strains colonized more quickly than S strains. Nevertheless, light-organ populations in field-caught adult squid often contain both D and S strains. We determined experimentally that this symbiont population heterogeneity might be achieved in nature by a serial encounter of different strains in the environment.},
}
@article {pmid30351431,
year = {2018},
author = {Yoro, E and Nishida, H and Ogawa-Ohnishi, M and Yoshida, C and Suzaki, T and Matsubayashi, Y and Kawaguchi, M},
title = {PLENTY, a hydroxyproline O-arabinosyltransferase, negatively regulates root nodule symbiosis in Lotus japonicus.},
journal = {Journal of experimental botany},
volume = {},
number = {},
pages = {},
doi = {10.1093/jxb/ery364},
pmid = {30351431},
issn = {1460-2431},
abstract = {Legumes can survive in nitrogen-deficient environments by forming root-nodule symbioses with rhizobial bacteria; however, forming nodules consumes energy, and nodule numbers must thus be strictly controlled. Previous studies identified major negative regulators of nodulation in Lotus japonicus, including the small peptides CLAVATA3/ESR (CLE)-RELATED-ROOT SIGNAL1 (CLE-RS1), CLE-RS2, and CLE-RS3, and their putative major receptor hypernodulation and aberrant root formation1 (HAR1). CLE-RS2 is known to be expressed in rhizobia-inoculated roots, and is predicted to be post-translationally arabinosylated, a modification essential for its activity. Moreover, all three CLE-RSs suppress nodulation in a HAR1-dependent manner. Here, we identified PLENTY as a responsible gene for the previously isolated hypernodulation mutant plenty. PLENTY encoded a hydroxyproline O-arabinosyltransferase orthologous to ROOT DETERMINED NODULATION1 in Medicago truncatula. PLENTY was localized to the Golgi, and an in vitro analysis of the recombinant protein demonstrated its arabinosylation activity, anticipating that CLE-RS1/2/3 may be substrates for PLENTY. The constitutive expression experiments showed that CLE-RS3 was the major candidate substrate for PLENTY, suggesting the substrate preference of PLENTY for individual CLE-RS peptides. Furthermore, a genetic analysis of the plentyhar1 double mutant indicated the existence of another PLENTY-dependent and HAR1-independent pathway negatively regulating nodulation.},
}
@article {pmid30350228,
year = {2018},
author = {Menegatti, C and Da Paixão Melo, WG and Carrão, DB and De Oliveira, ARM and Do Nascimento, FS and Lopes, NP and Pupo, MT},
title = {Paenibacillus polymyxa Associated with the Stingless Bee Melipona scutellaris Produces Antimicrobial Compounds against Entomopathogens.},
journal = {Journal of chemical ecology},
volume = {44},
number = {12},
pages = {1158-1169},
doi = {10.1007/s10886-018-1028-z},
pmid = {30350228},
issn = {1573-1561},
support = {2013/50954-0//Fundação de Amparo à Pesquisa do Estado de São Paulo/ ; 2014/17620-4//Fundação de Amparo à Pesquisa do Estado de São Paulo/ ; 2015/01001-6//Fundação de Amparo à Pesquisa do Estado de São Paulo/ ; 2009/54098-6//Fundação de Amparo à Pesquisa do Estado de São Paulo/ ; 2014/50265-3//Fundação de Amparo à Pesquisa do Estado de São Paulo/ ; 307147/2014-2//Conselho Nacional de Desenvolvimento Científico e Tecnológico/ ; },
abstract = {Social insects are frequently observed in symbiotic association with bacteria that produce antimicrobial natural products as a defense mechanism. There is a lack of studies on the microbiota associated with stingless bees and their antimicrobial compounds. To the best of our knowledge, this study is the first to report the isolation of Paenibacillus polymyxa ALLI-03-01 from the larval food of the stingless bee Melipona scutellaris. The bacterial strain was cultured under different conditions and produced (L)-(-)-3-phenyllactic acid and fusaricidins, which were active against entomopathogenic fungi and Paenibacillus larvae. Our results indicate that such natural products could be related to colony protection, suggesting a defense symbiosis between P. polymyxa ALLI-03-01 and Melipona scutellaris.},
}
@article {pmid30349546,
year = {2018},
author = {Battenberg, K and Potter, D and Tabuloc, CA and Chiu, JC and Berry, AM},
title = {Comparative Transcriptomic Analysis of Two Actinorhizal Plants and the Legume Medicagotruncatula Supports the Homology of Root Nodule Symbioses and Is Congruent With a Two-Step Process of Evolution in the Nitrogen-Fixing Clade of Angiosperms.},
journal = {Frontiers in plant science},
volume = {9},
number = {},
pages = {1256},
doi = {10.3389/fpls.2018.01256},
pmid = {30349546},
issn = {1664-462X},
abstract = {Root nodule symbiosis (RNS) is a symbiotic interaction established between angiosperm hosts and nitrogen-fixing soil bacteria in specialized organs called root nodules. The host plants provide photosynthate and the microsymbionts supply fixed nitrogen. The origin of RNS represents a major evolutionary event in the angiosperms, and understanding the genetic underpinnings of this event is of major economic and agricultural importance. Plants that engage in RNS are restricted to a single angiosperm clade known as the nitrogen-fixing clade (NFC), yet occur in multiple lineages scattered within the NFC. It has been postulated that RNS evolved in two steps: a gain-of-predisposition event occurring at the base of the NFC, followed by a gain-of-function event in each host plant lineage. Here, we first explore the premise that RNS has evolved from a single common background, and then we explore whether a two-step process better explains the evolutionary origin of RNS than either a single-step process, or multiple origins. We assembled the transcriptomes of root and nodule of two actinorhizal plants, Ceanothusthyrsiflorus and Datiscaglomerata. Together with the corresponding published transcriptomes of the model legume Medicagotruncatula, the gene expression patterns in roots and nodules were compared across the three lineages. We found that orthologs of many genes essential for RNS in the model legumes are expressed in all three lineages, and that the overall nodule gene expression patterns were more similar to each other than expected by random chance, a finding that supports a common evolutionary background for RNS shared by the three lineages. Moreover, phylogenetic analyses suggested that a substantial portion of the genes experiencing selection pressure changes at the base of the NFC also experienced additional changes at the base of each host plant lineage. Our results (1) support the occurrence of an event that led to RNS at the base of the NFC, and (2) suggest a subsequent change in each lineage, most consistent with a two-step origin of RNS. Among several conserved functions identified, strigolactone-related genes were down-regulated in nodules of all three species, suggesting a shared function similar to that shown for arbuscular mycorrhizal symbioses.},
}
@article {pmid30349006,
year = {2018},
author = {Daou, S and Barbour, H and Ahmed, O and Masclef, L and Baril, C and Sen Nkwe, N and Tchelougou, D and Uriarte, M and Bonneil, E and Ceccarelli, D and Mashtalir, N and Tanji, M and Masson, JY and Thibault, P and Sicheri, F and Yang, H and Carbone, M and Therrien, M and Affar, EB},
title = {Monoubiquitination of ASXLs controls the deubiquitinase activity of the tumor suppressor BAP1.},
journal = {Nature communications},
volume = {9},
number = {1},
pages = {4385},
doi = {10.1038/s41467-018-06854-2},
pmid = {30349006},
issn = {2041-1723},
support = {R01 CA198138/CA/NCI NIH HHS/United States ; },
abstract = {The tumor suppressor and deubiquitinase (DUB) BAP1 and its Drosophila ortholog Calypso assemble DUB complexes with the transcription regulators Additional sex combs-like (ASXL1, ASXL2, ASXL3) and Asx respectively. ASXLs and Asx use their DEUBiquitinase ADaptor (DEUBAD) domain to stimulate BAP1/Calypso DUB activity. Here we report that monoubiquitination of the DEUBAD is a general feature of ASXLs and Asx. BAP1 promotes DEUBAD monoubiquitination resulting in an increased stability of ASXL2, which in turn stimulates BAP1 DUB activity. ASXL2 monoubiquitination is directly catalyzed by UBE2E family of Ubiquitin-conjugating enzymes and regulates mammalian cell proliferation. Remarkably, Calypso also regulates Asx monoubiquitination and transgenic flies expressing monoubiquitination-defective Asx mutant exhibit developmental defects. Finally, the protein levels of ASXL2, BAP1 and UBE2E enzymes are highly correlated in mesothelioma tumors suggesting the importance of this signaling axis for tumor suppression. We propose that monoubiquitination orchestrates a molecular symbiosis relationship between ASXLs and BAP1.},
}
@article {pmid30347912,
year = {2018},
author = {Li, PY and Yang, G and Zhou, XT and Pu, CJ and Shao, AJ and Chen, ML},
title = {[Effect of soil pH on efficiency of mycorrhizal symbiosis on Salvia miltiorrhiza].},
journal = {Zhongguo Zhong yao za zhi = Zhongguo zhongyao zazhi = China journal of Chinese materia medica},
volume = {43},
number = {17},
pages = {3460-3465},
pmid = {30347912},
issn = {1001-5302},
abstract = {By comparing the effects of soil pH on the efficiency of mycorrhizal symbiosis on Salvia miltiorrhiza， the study is aimed to provide guidance for the use of mycorrhiza in the cultivation of S. miltiorrhiza. In this experiment, the inoculant treated and the non-inoculant treated control were grown in different soil pH. The data was collected after 60 days of cultivation including rate of mycorrhizal infection, biomass, and three chemical constituents with known medicinal action. The results showed that Glomus versiforme was more apt to infect S. miltiorrhiza (F>94.00%; M>69.45%; m>73.66%) and promote the growth of S. miltiorrhiza under pH 5-9 soil. The mycorrhizal contribution to the growth of S. miltiorrhiza was the highest when grown in pH 8 soil. Plants grown with mycorrhiza in pH 8 soil had above-ground biomass more than 2 times and root biomass more than 5 times. The uninoculated plants grew better under acidic and neutral conditions, but the inoculated plants grew better under alkaline (pH 8) conditions. This result showed mycorrhiza can play a role in the adaptability of S. miltiorrhiza to the environment. Inoculation of mycorrhiza significantly increased the accumulation of rosmarinic acid, salvianolic acid B, and dihydrotanshinone by 6.59,5.03 and 2.20-folds. Based on our results alkaline soil (pH 8) is most suitable for the cultivation of S. miltiorrhiza by inoculation with the mycorrhiza G. versiforme.},
}
@article {pmid30347445,
year = {2018},
author = {Buendia, L and Maillet, F and O'Connor, D and van de-Kerkhove, Q and Danoun, S and Gough, C and Lefebvre, B and Bensmihen, S},
title = {Lipo-chitooligosaccharides promote lateral root formation and modify auxin homeostasis in Brachypodium distachyon.},
journal = {The New phytologist},
volume = {},
number = {},
pages = {},
doi = {10.1111/nph.15551},
pmid = {30347445},
issn = {1469-8137},
support = {ANR-10-LABX-41//'Laboratoire d'Excellence LABEX' TULIP/ ; ANR-16-CE20-0025-01//ANR 'WHEATSYM'/ ; ANR-14-CE18-0008-01//ANR 'NICECROPS'/ ; //INRA/SPE project 'LCAux'/ ; //Ministère de l'Enseignement Supérieur et de la Recherche Scientifique/ ; },
abstract = {Lipo-chitooligosaccharides (LCOs) are microbial symbiotic signals that also influence root growth. In Medicago truncatula, LCOs stimulate lateral root formation (LRF) synergistically with auxin. However, the molecular mechanisms of this phenomenon and whether it is restricted to legume plants are not known. We have addressed the capacity of the model monocot Brachypodium distachyon (Brachypodium) to respond to LCOs and auxin for LRF. For this, we used a combination of root phenotyping assays, live-imaging and auxin quantification, and analysed the regulation of auxin homeostasis genes. We show that LCOs and a low dose of the auxin precursor indole-3-butyric acid (IBA) stimulated LRF in Brachypodium, while a combination of LCOs and IBA led to different regulations. Both LCO and IBA treatments locally increased endogenous indole-3-acetic acid (IAA) content, whereas the combination of LCO and IBA locally increased the endogenous concentration of a conjugated form of IAA (IAA-Ala). LCOs, IBA and the combination differentially controlled expression of auxin homeostasis genes. These results demonstrate that LCOs are active on Brachypodium roots and stimulate LRF probably through regulation of auxin homeostasis. The interaction between LCO and auxin treatments observed in Brachypodium on root architecture opens interesting avenues regarding their possible combined effects during the arbuscular mycorrhizal symbiosis.},
}
@article {pmid30347433,
year = {2018},
author = {Ivanov, S and Harrison, MJ},
title = {Accumulation of phosphoinositides in distinct regions of the periarbuscular membrane.},
journal = {The New phytologist},
volume = {},
number = {},
pages = {},
doi = {10.1111/nph.15553},
pmid = {30347433},
issn = {1469-8137},
support = {DBI-0618969//US NSF Instrumentation Grant/ ; CO29155//NYSTEM/ ; S10OD018516/GF/NIH HHS/United States ; IOS-1353367//US National Science Foundation/ ; IOS-1127155//US National Science Foundation/ ; },
abstract = {Phosphoinositides and phosphatidic acid are small anionic lipids that comprise a minor proportion of total membrane lipids in eukaryotic cells but influence a broad range of cellular processes including endomembrane trafficking, signaling, exocytosis and endocytosis. To investigate the spatial distribution of phosphoinositides during arbuscular mycorrhizal symbiosis, we generated fluorescent reporters of PI(4,5)P2 and PI4P, as well as phosphatidic acid and diacylglycerol and used them to monitor lipid distribution on the cytoplasmic side of membrane bilayers in colonized cortical cells. The PI4P reporter accumulated strongly on the periarbuscular membrane (PAM) and transiently labeled Golgi bodies, while the PA reporter showed differential labeling of endomembranes and the PAM. Surprisingly, the PI(4,5)P2 reporter accumulated in small, discrete regions of the PAM on the arbuscule trunks, frequently in two regions on opposing sides of the hypha. A mutant reporter with reduced PI(4,5)P2 binding capacity did not show these accumulations. The PI(4,5)P2 -rich regions were detected at all phases of arbuscule development following branching, co-localized with membrane marker proteins potentially indicating high membrane bilayer content, and were associated with an alteration in morphology of the hypha. A possible analogy to the biotrophic interfacial membrane complex formed in rice infected with Magnaporthe orzyae is discussed.},
}
@article {pmid30345347,
year = {2018},
author = {Liu, G and Bollier, D and Gübeli, C and Peter, N and Arnold, P and Egli, M and Borghi, L},
title = {Simulated microgravity and the antagonistic influence of strigolactone on plant nutrient uptake in low nutrient conditions.},
journal = {NPJ microgravity},
volume = {4},
number = {},
pages = {20},
doi = {10.1038/s41526-018-0054-z},
pmid = {30345347},
issn = {2373-8065},
abstract = {Human-assisted space exploration will require efficient methods of food production. Large-scale farming in presence of an Earth-like atmosphere in space faces two main challenges: plant yield in microgravity and plant nutrition in extraterrestrial soils, which are likely low in nutrients compared to terrestrial farm lands. We propose a plant-fungal symbiosis (i.e. mycorrhiza) as an efficient tool to increase plant biomass production in extraterrestrial environments. We tested the mycorrhization of Solanaceae on the model plant Petunia hybrida using the arbuscular mycorrhizal fungus Rhizophagus irregularis under simulated microgravity (s0-g) conditions obtained through a 3-D random positioning machine. Our results show that s0-g negatively affects mycorrhization and plant phosphate uptake by inhibiting hyphal elongation and secondary branching. However, in low nutrient conditions, the mycorrhiza can still support plant biomass production in s0-g when colonized plants have increased SL root exudation. Alternatively, s0-g in high nutrient conditions boosts tissue-specific cell division and cell expansion and overall plant size in Petunia, which has been reported for other plants species. Finally, we show that the SL mimic molecule rac-GR24 can still induce hyphal branching in vitro under simulated microgravity. Based on these results, we propose that in nutrient limited conditions strigolactone root exudation can challenge the negative microgravity effects on mycorrhization and therefore might play an important role in increasing the efficiency of future space farming.},
}
@article {pmid30344015,
year = {2018},
author = {Weger, BD and Gobet, C and Yeung, J and Martin, E and Jimenez, S and Betrisey, B and Foata, F and Berger, B and Balvay, A and Foussier, A and Charpagne, A and Boizet-Bonhoure, B and Chou, CJ and Naef, F and Gachon, F},
title = {The Mouse Microbiome Is Required for Sex-Specific Diurnal Rhythms of Gene Expression and Metabolism.},
journal = {Cell metabolism},
volume = {},
number = {},
pages = {},
doi = {10.1016/j.cmet.2018.09.023},
pmid = {30344015},
issn = {1932-7420},
abstract = {The circadian clock and associated feeding rhythms have a profound impact on metabolism and the gut microbiome. To what extent microbiota reciprocally affect daily rhythms of physiology in the host remains elusive. Here, we analyzed transcriptome and metabolome profiles of male and female germ-free mice. While mRNA expression of circadian clock genes revealed subtle changes in liver, intestine, and white adipose tissue, germ-free mice showed considerably altered expression of genes associated with rhythmic physiology. Strikingly, the absence of the microbiome attenuated liver sexual dimorphism and sex-specific rhythmicity. The resulting feminization of male and masculinization of female germ-free animals is likely caused by altered sexual development and growth hormone secretion, associated with differential activation of xenobiotic receptors. This defines a novel mechanism by which the microbiome regulates host metabolism.},
}
@article {pmid30343835,
year = {2018},
author = {Ji, Z and Liu, T and Zhang, J and Yan, H and Wang, E and Cui, Q and Chen, W and Chen, W},
title = {Genetic divergence among Bradyrhizobium strains nodulating wild and cultivated Kummerowia spp. in China.},
journal = {Systematic and applied microbiology},
volume = {},
number = {},
pages = {},
doi = {10.1016/j.syapm.2018.10.003},
pmid = {30343835},
issn = {1618-0984},
abstract = {Distribution of rhizobial species is affected by geographical isolation and selected by leguminous hosts, however, little is known about the molecular evolution of rhizobia nodulating the same legume in different eco-environments. In present study, the microevolution of Bradyrhizobium associated with the leguminous grass Kummerowia grown in exurban areas and cultivated in urban areas in China was investigated. Total 14 genospecies, including seven new groups, were identified based on a concatenated sequence analysis of taxonomic markers (SMc00019, truA and thrA) for 94 representative strains. Results demonstrated that lower levels of nucleotide diversity were found in the strains isolated from urban areas compared with those isolated from exurban areas, based on the evolutional analyses of three housekeeping genes (atpD, glnII and recA), two symbiosis-related genes (nodC and nifH), and the taxonomic markers. Moreover, compared with urban areas, gene exchange and recombination occurred more frequently among the genospecies isolated from exurban areas, regardless of the geographical distribution. Finally, the evolutionary lineage of Bradyrhizobium strains isolated from urban areas was independent of that of the strains isolated from exurban areas. In summary, the evolutionary history of Kummerowia bradyrhizobia may have been gradually segregated to different evolutionary lineages, irrespective of distinct biogeography.},
}
@article {pmid30333206,
year = {2018},
author = {Resl, P and Fernández-Mendoza, F and Mayrhofer, H and Spribille, T},
title = {The evolution of fungal substrate specificity in a widespread group of crustose lichens.},
journal = {Proceedings. Biological sciences},
volume = {285},
number = {1889},
pages = {},
doi = {10.1098/rspb.2018.0640},
pmid = {30333206},
issn = {1471-2954},
abstract = {Lichens exhibit varying degrees of specialization with regard to the surfaces they colonize, ranging from substrate generalists to strict substrate specialists. Though long recognized, the causes and consequences of substrate specialization are poorly known. Using a phylogeny of a 150-200 Mya clade of lichen fungi, we asked whether substrate niche is phylogenetically conserved, which substrates are ancestral, whether specialists arise from generalists or vice versa and how specialization affects speciation/extinction processes. We found strong phylogenetic signal for niche conservatism. Specialists evolved into generalists and back again, but transitions from generalism to specialism were more common than the reverse. Our models suggest that for this group of fungi, 'escape' from specialization for soil, rock and bark occurred, but specialization for wood foreclosed evolution away from that substrate type. In parallel, speciation models showed positive diversification rates for soil and rock dwellers but not other specialists. Patterns in the studied group suggest that fungal substrate specificity is a key determinant of evolutionary trajectory for the entire lichen symbiosis.},
}
@article {pmid30332850,
year = {2018},
author = {Xu, Y and Zhu, S and Liu, F and Wang, W and Wang, X and Han, G and Cheng, B},
title = {Identification of Arbuscular Mycorrhiza Fungi Responsive microRNAs and Their Regulatory Network in Maize.},
journal = {International journal of molecular sciences},
volume = {19},
number = {10},
pages = {},
doi = {10.3390/ijms19103201},
pmid = {30332850},
issn = {1422-0067},
support = {31470465; 31770476//National Natural Science Foundation of China/ ; 15czz03119//Science and Technology Major Project of Anhui Province/ ; 1708085MC53; 1708085QC53//Project of Natural Science Foundation of Anhui Province/ ; },
abstract = {Maize can form symbiotic relationships with arbuscular mycorrhiza (AM) fungus to increase productivity and resistance, but the miRNAs in maize responsible for this process have not been discovered. In this study, 155 known and 28 novel miRNAs were identified by performing high-throughput sequencing of sRNA in maize roots colonized by AM fungi. Similar to the profiles in other AM-capable plants, a large proportion of identified maize miRNAs were 24 nt in length. Fourteen and two miRNAs were significantly down- and up-regulated in response to AM fungus Glomus intraradices inoculation, respectively, suggesting potential roles of these miRNAs in AM symbiosis. Interestingly, 12 of 14 significantly down-regulated known maize miRNAs belong to the miR399 family, which was previously reported to be involved in the interaction between Medicagotruncatula and AM fungi. This result indicated that the miR399 family should regulate AM symbiosis conservatively across different plant lineages. Pathway and network analyses showed that the differentially expressed miRNAs might regulate lipid metabolism and phosphate starvation response in maize during the symbiosis process via their target genes. Several members of the miR399 family and the miR397 family should be involved in controlling the fatty acid metabolism and promoting lipid delivering from plants to AM fungi. To the best of our knowledge, this is the first report on miRNAs mediating fatty acids from plant to AM fungi. This study provides insight into the regulatory roles of miRNAs in the symbiosis between plants and AM fungi.},
}
@article {pmid30332427,
year = {2018},
author = {Chang, NN and Lin, LH and Tu, TH and Jeng, MS and Chikaraishi, Y and Wang, PL},
title = {Trophic structure and energy flow in a shallow-water hydrothermal vent: Insights from a stable isotope approach.},
journal = {PloS one},
volume = {13},
number = {10},
pages = {e0204753},
doi = {10.1371/journal.pone.0204753},
pmid = {30332427},
issn = {1932-6203},
abstract = {Shallow-water hydrothermal vent ecosystems are distinct from the deep-sea counterparts, because they are in receipt of sustenance from both chemosynthetic and photosynthetic production and have a lack of symbiosis. The trophic linkage and energy flow in these ecosystems, however remain elusive, which allows us poor understanding of the whole spectrum of biological components distributed across such environmental gradients. In this study, a thorough isotopic survey was conducted on various biological specimens and suspended particulates collected along four transects across the venting features of a shallow-water hydrothermal field off Kueishan Island, Taiwan. The isotope data combined with a Bayesian-based mixing model indicate that the vent-associated particulate organic matter (vent POM), as primary contribution of chemoautotrophic populations, has a high δ13C value (-18.2 ± 1.1‰) and a low δ15N value (-1.7 ± 0.4‰). Zooplankton and epibenthic crustaceans, as the fundamental consumers, exhibit δ13C and δ15N values ranging from -21.3 to -19.8‰ and +5.1 to +7.5‰, respectively, and can utilize the vent POM for 38-53% of their diets. The vent-obligate crab Xenograpsus testudinatus shows a large variation in δ13C (from -18.8 to -13.9‰) and δ15N values (from 1.1 to 9.8‰), although an omnivorous trophic level (2.5) is identified for it using δ15N values of amino acids, and it can utilize the vent POM for 6-87% of its diet. The consistently low (< 10.0‰) and overlapping δ15N values for most of the analyzed macroinvertebrates suggest extensive ingestion of chemosynthetic production complementing the photosynthetic production, a weak prey-predator relationship and low trophic complexity possibly imposed by the extreme environmental contexts of shallow-water hydrothermal ecosystems.},
}
@article {pmid30326664,
year = {2018},
author = {Isidra-Arellano, MC and Reyero-Saavedra, MDR and Sánchez-Correa, MDS and Pingault, L and Sen, S and Joshi, T and Girard, L and Castro-Guerrero, NA and Mendoza-Cozatl, DG and Libault, M and Valdés-López, O},
title = {Phosphate Deficiency Negatively Affects Early Steps of the Symbiosis between Common Bean and Rhizobia.},
journal = {Genes},
volume = {9},
number = {10},
pages = {},
doi = {10.3390/genes9100498},
pmid = {30326664},
issn = {2073-4425},
support = {IN213017//Programa de Apoyo a Proyectos de Investigación e Inovación Tecnológica (PAPIIT)/ ; IOS-1339194//National Science Foundation/ ; IOS-1453613//National Science Foundation/ ; 919676//Consejo Nacional de Ciencia y Tecnología/ ; 347027/239879//Consejo Nacional de Ciencia y Tecnología/ ; },
abstract = {Phosphate (Pi) deficiency reduces nodule formation and development in different legume species including common bean. Despite significant progress in the understanding of the genetic responses underlying the adaptation of nodules to Pi deficiency, it is still unclear whether this nutritional deficiency interferes with the molecular dialogue between legumes and rhizobia. If so, what part of the molecular dialogue is impaired? In this study, we provide evidence demonstrating that Pi deficiency negatively affects critical early molecular and physiological responses that are required for a successful symbiosis between common bean and rhizobia. We demonstrated that the infection thread formation and the expression of PvNSP2, PvNIN, and PvFLOT2, which are genes controlling the nodulation process were significantly reduced in Pi-deficient common bean seedlings. In addition, whole-genome transcriptional analysis revealed that the expression of hormones-related genes is compromised in Pi-deficient seedlings inoculated with rhizobia. Moreover, we showed that regardless of the presence or absence of rhizobia, the expression of PvRIC1 and PvRIC2, two genes participating in the autoregulation of nodule numbers, was higher in Pi-deficient seedlings compared to control seedlings. The data presented in this study provides a mechanistic model to better understand how Pi deficiency impacts the early steps of the symbiosis between common bean and rhizobia.},
}
@article {pmid30325166,
year = {2018},
author = {Ma, YY and Zhang, HC and Xiang, XJ and Wang, DZ and Guo, XS and Guo, ZB and Sun, RB and Chu, HY},
title = {Effects of long-term fertilization on arbuscular mycorrhizal fungal community in lime concretion black soil.},
journal = {Ying yong sheng tai xue bao = The journal of applied ecology},
volume = {29},
number = {10},
pages = {3398-3406},
doi = {10.13287/j.1001-9332.201810.035},
pmid = {30325166},
issn = {1001-9332},
mesh = {Agriculture ; Calcium Compounds ; Crops, Agricultural ; Fertilizers ; Glomeromycota ; Manure ; *Mycorrhizae ; Oxides ; Plant Roots ; Soil ; Soil Microbiology ; Symbiosis ; Triticum ; },
abstract = {In agroecosystem, arbuscular mycorrhizal fungi have mutually beneficial symbiosis with roots of many crops. Meanwhile, this special fungal community is also affected by agricultural mana-gements such as fertilization. The objective of this study was to investigate the effects of long-term fertilization managements (no fertilizer, chemical fertilizer, chemical fertilizer combined with straw, chemical fertilizer combined with manure) on arbuscular mycorrhizal fungal community (AM fungal community) in lime concretion black soil, and to identify the indicator species in each fertilization regime. The most dominant arbuscular mycorrhizal fungal phyla in lime concretion black soil were Archaeosporaceae, Diversisporaceae, Gigasporaceae, Claroideoglomeraceae, Glomeraceae and Paraglomeraceae. The genus Paraglomus was strongly and significantly associated with the application of chemical fertilizer and organic fertilizer. Compared with the control, long-term application of chemical fertilizer greatly changed AM fungal community structure and resulted in the decrease of AM fungal diversity, and the addition of wheat straw further decreased the diversity, while the addition of manure could alleviate diversity loss resulted from chemical fertilization. Soil pH and dissolved organic carbon (DOC) were the main factors affecting the changes of AM fungal community. In summary, long-term application of chemical fertilizer combined with different organic materials had different impacts on soil AM fungal community structure and diversity. The combination of chemical fertilizer and manure would be more conducive to the maintenance of AM fungal diversity.},
}
@article {pmid30324505,
year = {2018},
author = {Guillermo Bueno, C and Gerz, M and Zobel, M and Moora, M},
title = {Conceptual differences lead to divergent trait estimates in empirical and taxonomic approaches to plant mycorrhizal trait assignment.},
journal = {Mycorrhiza},
volume = {},
number = {},
pages = {},
doi = {10.1007/s00572-018-0869-1},
pmid = {30324505},
issn = {1432-1890},
support = {IUT 20-28//Eesti Teadusagentuur/ ; Center of excellence Ecolchange//European Regional Development Fund/ ; },
abstract = {Empirical and taxonomic approaches are the two main methods used to assign plant mycorrhizal traits to species lists. While the empirical approach uses only available empirical information, the taxonomic approach extrapolates certain core information about plant mycorrhizal types and statuses to related species. Despite recent claims that the taxonomic approach is now almost definitive, with little benefit to be gained from further empirical data collection, it has not been thoroughly compared with the empirical approach. Using the most complete available plant mycorrhizal trait information for Europe and both assignment approaches, we calculate the proportion of species for each trait, and model environmental drivers of trait distribution across the continent. We found large degrees of mismatch between approaches, with consequences for biogeographical interpretation, among facultatively mycorrhizal (FM; 91% of species mismatched), non-mycorrhizal (NM; 45%), and to a lesser extent arbuscular mycorrhizal (AM; 16%) plant species. This can partly be attributed to the taxonomic precision of the taxonomic approach and the use of different AM, NM, and FM concepts. Our results showed that the extrapolations of the taxonomic approach do not consistently match with empirical information and indicate that more empirical data are needed, in particular for FM, NM, and AM plant species. Clarifying certain concepts underlying mycorrhizal traits and empirically describing NM, AM, and FM species within plant families can greatly improve our understanding of the biogeography of mycorrhizal symbiosis.},
}
@article {pmid30322931,
year = {2018},
author = {Shukla, SP and Plata, C and Reichelt, M and Steiger, S and Heckel, DG and Kaltenpoth, M and Vilcinskas, A and Vogel, H},
title = {Microbiome-assisted carrion preservation aids larval development in a burying beetle.},
journal = {Proceedings of the National Academy of Sciences of the United States of America},
volume = {115},
number = {44},
pages = {11274-11279},
doi = {10.1073/pnas.1812808115},
pmid = {30322931},
issn = {1091-6490},
abstract = {The ability to feed on a wide range of diets has enabled insects to diversify and colonize specialized niches. Carrion, for example, is highly susceptible to microbial decomposers, but is kept palatable several days after an animal's death by carrion-feeding insects. Here we show that the burying beetle Nicrophorus vespilloides preserves carrion by preventing the microbial succession associated with carrion decomposition, thus ensuring a high-quality resource for their developing larvae. Beetle-tended carcasses showed no signs of degradation and hosted a microbial community containing the beetles' gut microbiota, including the yeast Yarrowia In contrast, untended carcasses showed visual and olfactory signs of putrefaction, and their microbial community consisted of endogenous and soil-originating microbial decomposers. This regulation of the carcass' bacterial and fungal community and transcriptomic profile was associated with lower concentrations of putrescine and cadaverine (toxic polyamines associated with carcass putrefaction) and altered levels of proteases, lipases, and free amino acids. Beetle-tended carcasses develop a biofilm-like matrix housing the yeast, which, when experimentally removed, leads to reduced larval growth. Thus, tended carcasses hosted a mutualistic microbial community that promotes optimal larval development, likely through symbiont-mediated extraintestinal digestion and detoxification of carrion nutrients. The adaptive preservation of carrion coordinated by the beetles and their symbionts demonstrates a specialized resource-management strategy through which insects modify their habitats to enhance fitness.},
}
@article {pmid30322086,
year = {2018},
author = {Liao, D and Wang, S and Cui, M and Liu, J and Chen, A and Xu, G},
title = {Phytohormones Regulate the Development of Arbuscular Mycorrhizal Symbiosis.},
journal = {International journal of molecular sciences},
volume = {19},
number = {10},
pages = {},
doi = {10.3390/ijms19103146},
pmid = {30322086},
issn = {1422-0067},
abstract = {Most terrestrial plants are able to form a root symbiosis with arbuscular mycorrhizal (AM) fungi for enhancing the assimilation of mineral nutrients. AM fungi are obligate symbionts that depend on host plants as their sole carbon source. Development of an AM association requires a continuous signal exchange between the two symbionts, which triggers coordinated differentiation of both partners, to enable their interaction within the root cells. The control of the AM symbiosis involves a finely-tuned process, and an increasing number of studies have pointed to a pivotal role of several phytohormones, such as strigolactones (SLs), gibberellic acids (GAs), and auxin, in the modulation of AM symbiosis, through the early recognition of events up to the final arbuscular formation. SLs are involved in the presymbiotic growth of the fungus, while auxin is required for both the early steps of fungal growth and the differentiation of arbuscules. GAs modulate arbuscule formation in a dose-dependent manner, via DELLA proteins, a group of GRAS transcription factors that negatively control the GA signaling. Here, we summarize the recent findings on the roles of these plant hormones in AM symbiosis, and also explore the current understanding of how the DELLA proteins act as central regulators to coordinate plant hormone signaling, to regulate the AM symbiosis.},
}
@article {pmid30320901,
year = {2018},
author = {Dos Santos Lima Fagotti, D and Abrantes, JLF and Cerezini, P and Fukami, J and Nogueira, MA and Del Cerro, P and Valderrama-Fernández, R and Ollero, FJ and Megías, M and Hungria, M},
title = {Quorum sensing communication: Bradyrhizobium-Azospirillum interaction via N-acyl-homoserine lactones in the promotion of soybean symbiosis.},
journal = {Journal of basic microbiology},
volume = {},
number = {},
pages = {},
doi = {10.1002/jobm.201800324},
pmid = {30320901},
issn = {1521-4028},
support = {Ciência sem Fronteiras 400205/2012-2//Conselho Nacional de Desenvolvimento Científico e Tecnológico/ ; 02.13.08.001.00.00//Empresa Brasileira de Pesquisa Agropecuária/ ; CNPq-465133/2014-2, Fundação Araucaria-STI, CAPE//INCT-Plant-Growth Promoting Microorganisms for Agricultural Sustainability and Environmental Responsibility/ ; Mineco, AGL2016-77163-R//Ministerio de Economía y Competitividad/ ; },
abstract = {Quorum-sensing (QS) mechanisms are important in intra- and inter-specific communication among bacteria. We investigated QS mechanisms in Bradyrhizobium japonicum strain CPAC 15 and Azospirillum brasilense strains Ab-V5 and Ab-V6, used in commercial co-inoculants for the soybean crop in Brazil. A transconjugant of CPAC 15-QS with partial inactivation of N-acyl-homoserine lactones (AHLs) was obtained and several parameters were evaluated; in vitro, CPAC 15 and the transconjugant differed in growth, but not in biofilm formation, and no differences were observed in the symbiotic performance in vivo. The genome of CPAC 15 carries functional luxI and luxR genes and low amounts of three AHL molecules were detected: 3-OH-C12-AHL, 3-OH-C14-AHL, and 3-oxo-C14-AHL. Multiple copies of luxR-like genes, but not of luxI are present in the genomes of Ab-V5 and Ab-V6, and differences in gene expression were observed when the strains were co-cultured with B. japonicum; we may infer that the luxR-genes of A. brasilense may perceive the AHL molecules of B. japonicum. Soybean symbiotic performance was improved especially by co-inoculation with Ab-V6, which, contrarily to Ab-V5, did not respond to the AHLs of CPAC 15. We concluded that A. brasilense Ab-V5, but not Ab-V6, responded to the QS signals of CPAC 15, and that the synergistic interaction may be credited, at least partially, to the QS interaction. In addition, we confirmed inter- and intra-species QS communication between B. japonicum and A. brasilense and, for Azospirillum, at the strain level, impacting several steps of the symbiosis, from cell growth to plant nodulation and growth.},
}
@article {pmid30320217,
year = {2018},
author = {Kremer, N and Koch, EJ and El Filali, A and Zhou, L and Heath-Heckman, EAC and Ruby, EG and McFall-Ngai, MJ},
title = {Persistent Interactions with Bacterial Symbionts Direct Mature-Host Cell Morphology and Gene Expression in the Squid-Vibrio Symbiosis.},
journal = {mSystems},
volume = {3},
number = {5},
pages = {},
doi = {10.1128/mSystems.00165-18},
pmid = {30320217},
issn = {2379-5077},
support = {R01 AI050661/AI/NIAID NIH HHS/United States ; R01 OD011024/OD/NIH HHS/United States ; R37 AI050661/AI/NIAID NIH HHS/United States ; },
abstract = {In horizontally transmitted symbioses, structural, biochemical, and molecular features both facilitate host colonization by specific symbionts and mediate their persistent carriage. In the association between the squid Euprymna scolopes and its luminous bacterial partner Vibrio fischeri, the symbionts interact with two epithelial fields; they interact (i) transiently with the superficial ciliated field that potentiates colonization and regresses within days of colonization and (ii) persistently with the cells that line the internal crypts, whose ultrastructure changes in response to the symbionts. Development of the association creates conditions that promote the symbiotic partner over the lifetime of the host. To determine whether light organ maturation requires continuous interactions with V. fischeri or only the signaling that occurs during its initiation, we compared 4-week-old squid that were uncolonized with those colonized either persistently by wild-type V. fischeri or transiently by a V. fischeri mutant that triggers early events in morphogenesis but does not persist. Microscopic analysis of the light organs showed that, while morphogenesis of the superficial ciliated field is greatly accelerated by V. fischeri colonization, its eventual outcome is largely independent of colonization state. In contrast, the symbiont-induced changes in crypt cell shape require persistent host-symbiont interaction, reflected in the similarity between uncolonized and transiently colonized animals. Transcriptomic analyses reflected the microscopy results; host gene expression at 4 weeks was due primarily to the persistent interactions of host and symbiont cells. Further, the transcriptomic signature of specific pathways reflected the daily rhythm of symbiont release and regrowth and required the presence of the symbionts. IMPORTANCE A long-term relationship between symbiotic partners is often characterized by development and maturation of host structures that harbor the symbiont cells over the host's lifetime. To understand the mechanisms involved in symbiosis maintenance more fully, we studied the mature bobtail squid, whose light-emitting organ, under experimental conditions, can be transiently or persistently colonized by Vibrio fischeri or remain uncolonized. Superficial anatomical changes in the organ were largely independent of symbiosis. However, both the microanatomy of cells with which symbionts interact and the patterns of gene expression in the mature animal were due principally to the persistent interactions of host and symbiont cells rather than to a response to early colonization events. Further, the characteristic pronounced daily rhythm on the host transcriptome required persistent V. fischeri colonization of the organ. This experimental study provides a window into how persistent symbiotic colonization influences the form and function of host animal tissues.},
}
@article {pmid30319665,
year = {2018},
author = {Buhian, WP and Bensmihen, S},
title = {Mini-Review: Nod Factor Regulation of Phytohormone Signaling and Homeostasis During Rhizobia-Legume Symbiosis.},
journal = {Frontiers in plant science},
volume = {9},
number = {},
pages = {1247},
doi = {10.3389/fpls.2018.01247},
pmid = {30319665},
issn = {1664-462X},
abstract = {The rhizobia-legume symbiosis is a mutualistic association in which bacteria provide plants with nitrogen compounds and the plant provides bacteria with carbon sources. A successful symbiotic interaction relies on a molecular dialog between the plant and the bacteria, and generally involves rhizobial lipo-chitooligosaccharide signals called Nod factors (NFs). In most cases, specific NF perception is required for rhizobia to enter root cells through newly formed intracellular structures called infection threads (ITs). Concomitantly to IT formation in root hairs, root cortical cells start to divide to create a new root organ called the nodule, which will provide the bacteria with a specific micro-environment required for symbiotic nitrogen fixation. During all these steps of plant-bacteria interaction, new plant cellular compartments and developmental programs are activated. This interaction is costly for the plant that tightly controls symbiosis establishment and functioning. Phytohormones are key regulators of cellular and developmental plasticity in plants, and they are influential endogenous signals that rapidly control plant responses. Although early symbiotic responses were known for decades to be linked to phytohormone-related responses, new data reveal the molecular mechanisms involved and links between phytohormones and the control of early symbiotic events. Reciprocally, NF signaling also targets phytohormone signaling pathways. In this review, we will focus on the emerging notion of NF and phytohormone signaling crosstalk, and how it could contribute to the tight control of symbiosis establishment in legume host plants.},
}
@article {pmid30319574,
year = {2018},
author = {Santos-Garcia, D and Juravel, K and Freilich, S and Zchori-Fein, E and Latorre, A and Moya, A and Morin, S and Silva, FJ},
title = {To B or Not to B: Comparative Genomics Suggests Arsenophonus as a Source of B Vitamins in Whiteflies.},
journal = {Frontiers in microbiology},
volume = {9},
number = {},
pages = {2254},
doi = {10.3389/fmicb.2018.02254},
pmid = {30319574},
issn = {1664-302X},
abstract = {Insect lineages feeding on nutritionally restricted diets such as phloem sap, xylem sap, or blood, were able to diversify by acquiring bacterial species that complement lacking nutrients. These bacteria, considered obligate/primary endosymbionts, share a long evolutionary history with their hosts. In some cases, however, these endosymbionts are not able to fulfill all of their host's nutritional requirements, driving the acquisition of additional symbiotic species. Phloem-feeding members of the insect family Aleyrodidae (whiteflies) established an obligate relationship with Candidatus Portiera aleyrodidarum, which provides its hots with essential amino acids and carotenoids. In addition, many whitefly species harbor additional endosymbionts which may potentially further supplement their host's diet. To test this hypothesis, genomes of several endosymbionts of the whiteflies Aleurodicus dispersus, Aleurodicus floccissimus and Trialeurodes vaporariorum were analyzed. In addition to Portiera, all three species were found to harbor one Arsenophonus and one Wolbachia endosymbiont. A comparative analysis of Arsenophonus genomes revealed that although all three are capable of synthesizing B vitamins and cofactors, such as pyridoxal, riboflavin, or folate, their genomes and phylogenetic relationship vary greatly. Arsenophonus of A. floccissimus and T. vaporariorum belong to the same clade, and display characteristics of facultative endosymbionts, such as large genomes (3 Mb) with thousands of genes and pseudogenes, intermediate GC content, and mobile genetic elements. In contrast, Arsenophonus of A. dispersus belongs to a different lineage and displays the characteristics of a primary endosymbiont-a reduced genome (670 kb) with ~400 genes, 32% GC content, and no mobile genetic elements. However, the presence of 274 pseudogenes suggests that this symbiotic association is more recent than other reported primary endosymbionts of hemipterans. The gene repertoire of Arsenophonus of A. dispersus is completely integrated in the symbiotic consortia, and the biosynthesis of most vitamins occurs in shared pathways with its host. In addition, Wolbachia endosymbionts have also retained the ability to produce riboflavin, flavin adenine dinucleotide, and folate, and may make a nutritional contribution. Taken together, our results show that Arsenophonus hold a pivotal place in whitefly nutrition by their ability to produce B vitamins.},
}
@article {pmid30317641,
year = {2018},
author = {Fabiańska, I and Gerlach, N and Almario, J and Bucher, M},
title = {Plant-mediated effects of soil phosphorus on the root-associated fungal microbiota in Arabidopsis thaliana.},
journal = {The New phytologist},
volume = {},
number = {},
pages = {},
doi = {10.1111/nph.15538},
pmid = {30317641},
issn = {1469-8137},
support = {GA-2010-267243//FP7 Marie Curie Actions/ ; EXC 1028//Cluster of Excellence on Plant Sciences/ ; //International Max Planck Research School (IMPRS) Cologne on 'Understanding Complex Plant Traits using Computational and Evolutionary Approaches'/ ; },
abstract = {Plants respond to phosphorus (P) limitation through an array of morphological, physiological and metabolic changes which are part of the phosphate (Pi) starvation response (PSR). This response influences the establishment of the arbuscular mycorrhizal (AM) symbiosis in most land plants. It is, however, unknown to what extent available P and the PSR redefine plant interactions with the fungal microbiota in soil. Using amplicon sequencing of the fungal taxonomic marker ITS2, we examined the changes in root-associated fungal communities in the AM nonhost species Arabidopsis thaliana in response to soil amendment with P and to genetic perturbations in the plant PSR. We observed robust shifts in root-associated fungal communities of P-replete plants in comparison with their P-deprived counterparts, while bulk soil communities remained unaltered. Moreover, plants carrying mutations in the phosphate signaling network genes, phr1, phl1 and pho2, exhibited similarly altered root fungal communities characterized by the depletion of the chytridiomycete taxon Olpidium brassicae specifically under P-replete conditions. This study highlights the nutritional status and the underlying nutrient signaling network of an AM nonhost plant as previously unrecognized factors influencing the assembly of the plant fungal microbiota in response to P in nonsterile soil.},
}
@article {pmid30316924,
year = {2019},
author = {Chew, SF and Koh, CZY and Hiong, KC and Choo, CYL and Wong, WP and Neo, ML and Ip, YK},
title = {Light-enhanced expression of Carbonic Anhydrase 4-like supports shell formation in the fluted giant clam Tridacna squamosa.},
journal = {Gene},
volume = {683},
number = {},
pages = {101-112},
doi = {10.1016/j.gene.2018.10.023},
pmid = {30316924},
issn = {1879-0038},
mesh = {Animal Shells/metabolism/physiology ; Animals ; Bivalvia/genetics/*physiology ; Carbonic Anhydrase IV/*genetics/metabolism ; Cloning, Molecular/*drug effects ; Open Reading Frames ; Phylogeny ; Sequence Analysis, DNA ; Tissue Distribution ; Up-Regulation ; },
abstract = {Giant clams represent symbiotic associations between a host clam and its extracellular zooxanthellae. They are able to grow in nutrient-deficient tropical marine environments and conduct light-enhanced shell formation (calcification) with the aid of photosynthates donated by the symbiotic zooxanthellae. In light, there is a high demand for inorganic carbon (Ci) to support photosynthesis in the symbionts and light-enhanced calcification in the host. In this study, we cloned and characterized a host Carbonic Anhydrase 4 homolog (CA4-like) from the whitish inner mantle of the giant clam Tridacna squamosa. The full cDNA coding sequence of CA4-like consisted of 1002 bp, encoding for 334 amino acids of 38.5 kDa. The host CA4-like was phenogramically distinct from algal CAs. The transcript level of CA4-like in the inner mantle was ~3-fold higher than those in the colorful outer mantle and the ctenidium. In the inner mantle, CA4-like was immunolocalized in the apical membrane of the seawater-facing epithelial cells, but absent from the shell-facing epithelium. Hence, CA4-like was positioned to catalyze the conversion of HCO3- to CO2 in the ambient seawater which would facilitate CO2 uptake. The absorbed CO2 could be converted back to HCO3- by the cytoplasmic CA2-like. As the protein abundance of CA4-like increased in the inner mantle after 6 or 12 h of light exposure, there could be an augmentation of the total CA4-like activity to increase Ci uptake in light. It is plausible that the absorbed Ci was allocated preferentially for shell formation due to the close proximity of the seawater-facing epithelium to the shell-facing epithelium in the inner mantle that contains only few zooxanthellae.},
}
@article {pmid30315860,
year = {2018},
author = {Zhou, Z and Liu, Z and Wang, L and Luo, J and Li, H},
title = {Oxidative stress, apoptosis activation and symbiosis disruption in giant clam Tridacna crocea under high temperature.},
journal = {Fish &amp; shellfish immunology},
volume = {84},
number = {},
pages = {451-457},
doi = {10.1016/j.fsi.2018.10.033},
pmid = {30315860},
issn = {1095-9947},
abstract = {Giant clams are one of the most important animals in coral reef ecosystem, and its growth and reproduction are being threatened by heat stress due to global warming. In the present study, the symbiont density, the crucial enzyme activities and the transcriptome were investigated in the outer mantle of giant clam Tridacna crocea after the acute exposure of high temperature. The density of symbiotic zooxanthellae decreased significantly during 12-24 h, with the minimum level (7.75 × 105 cell cm-2, p < 0.05) at 12 h after heat stress. The activities of superoxide dismutase in the heat stress group was significantly lower than that in the control group at 24 h after heat stress, while no significant change in the activities of catalase was observed during the entire stress process. The activation level of caspase3 began to increase significantly at 12 h (1.22-fold, p < 0.05), and reached the highest level at 24 h (1.38-fold, p < 0.05) after heat stress. Six paired-end libraries were sequenced in two groups, including the heat stress and control group at 12 h after heat stress. Through the assembling of 187,116,632 paired-end reads with lengths of 2 × 150 bp, a total of 26,676 genes were obtained which derived from giant clam. Bioinformatics analysis revealed 47 significantly upregulated and 88 significantly downregulated genes at 12 h after the treatment. There were 12 overrepresented GO terms for significantly upregulated genes, mostly related to unfolded protein binding and ATP binding, whereas no GO term was overrepresented for significantly downregulated genes. These results collectively suggest high temperature could induce excessive oxidative stress through the repressed antioxidant ability, the apoptosis activated by the unfolded protein response, and further the collapse of the symbiosis between host and symbiont, which has been threatening the growth and reproduction of the giant clam T. crocea.},
}
@article {pmid30315373,
year = {2018},
author = {Ribeiro-Barros, AI and Catarino, S and Moura, I and Ramalho, JC and Romeiras, MM and Ghodhbane-Gtari, F},
title = {Actinorhizal trees and shrubs from Africa: distribution, conservation and uses.},
journal = {Antonie van Leeuwenhoek},
volume = {},
number = {},
pages = {},
doi = {10.1007/s10482-018-1174-x},
pmid = {30315373},
issn = {1572-9699},
support = {UID/AGR/04129/2013 (LEAF)//Fundação para a Ciência e a Tecnologia/ ; UID/GEO/04035/2013 (GeoBioTec)//Fundação para a Ciência e a Tecnologia/ ; },
abstract = {Actinorhizal plants are a group of perennial dicotyledonous angiosperms, comprised of more than 200 species, most of which can establish root-nodule symbiosis with the nitrogen fixing actinobacteria of the genus Frankia. They are key providers of fundamental goods and services and can give a major contribution to mitigate the combined effects of climate changes, human population growth and loss of biodiversity. This aspect is particularly relevant for the developing economies of many African countries, which are highly exposed to climate and anthropogenic disturbances. In this work we have analyzed the distribution, conservation and uses of actinorhizal species native to or introduced in Africa. A total of 42 taxa distributed over six botanical families (Betulaceae, Casuarinaceae, Myricaceae, Elaeagnaceae, Rhamnaceae and Coriariaceae) were identified. The vast majority is able to thrive under a range of diverse environments and has multiple ecological and economic potential. More than half of the identified species belong to the genus Morella (Myricaceae), most of them native to Middle, Eastern and Southern Africa. Although the information about the conservation status and uses of Morella spp. is largely incomplete, the available data is indicative of their potential in e.g. forestry and agroforestry, food and medicine. Therefore, efforts should be made to upgrade actinorhizal research in Africa towards the sustainable use of biodiversity at the service of local (bio)economies.},
}
@article {pmid30313634,
year = {2018},
author = {ŠobÁŇovÁ, A and ĎuriŠ, Z},
title = {Kaviengella jeffkinchi, a new genus and species of symbiotic shrimp (Crustacea: Decapoda: Palaemonidae) from Papua New Guinea.},
journal = {Zootaxa},
volume = {4415},
number = {1},
pages = {118-134},
doi = {10.11646/zootaxa.4415.1.5},
pmid = {30313634},
issn = {1175-5334},
abstract = {A very small adult specimen of symbiotic palaemonid shrimp collected from Kavieng Lagoon, N.W. New Ireland Island, Papua New Guinea, is described as a new genus and species. Due to the slender subcylindrical body, reduced rostrum, elongated eyes and distolaterally produced uropodal exopods, the new species is somewhat similar to shrimps of the endosymbiotic sponge genus Nippontonia. Both second pereiopods are lost, but the specimen is unique by its bidentate scaphocerites, an apical corona of spiniform teeth on the mandibular molar process, five posterior telson cuspidate setae from which the median and intermediate ones are long, hooked, and the broadly spoon-like dactyli of the first pereiopods chelae with marginal pectination. Based on those characters, the new genus is without parallel among all symbiotic palaemonid shrimps. Its close phylogenetic relationship to the spongobiotic genera Nippontonia, Onycocaridella, and Thaumastocaris, is also confirmed by molecular comparison.},
}
@article {pmid30313270,
year = {2018},
author = {Osawa, M and Naruse, T and Ng, PKL},
title = {New records of species of the Polyonyx sinensis group (Crustacea: Decapoda: Anomura: Porcellanidae) from Japan, the Philippines, Singapore, and Malaysia, with descriptions of two new species.},
journal = {Zootaxa},
volume = {4429},
number = {2},
pages = {303-323},
doi = {10.11646/zootaxa.4429.2.6},
pmid = {30313270},
issn = {1175-5334},
abstract = {Five species of the genus Polyonyx Stimpson, 1858 are reported from southern Japan, the Philippines, Singapore, and Peninsular Malaysia. All of them belong to the P. sinensis group, which is morphologically defined by having the dactyli of the ambulatory legs each with the dorsal claw being much smaller than the ventral claw. Two species are described as new to science, one each from Peninsular Malaysia and the Ryukyu Islands in Japan, and their affinities are discussed. Polyonyx boucheti Osawa, 2007, P. heok Osawa Ng, 2016, and P. thai Werding, 2001, are also newly reported from southern Japan, the Philippines, and Singapore. A key to the Indo-West Pacific species of the P. sinensis group is provided.},
}
@article {pmid30312435,
year = {2018},
author = {An, J and Sun, M and van Velzen, R and Ji, C and Zheng, Z and Limpens, E and Bisseling, T and Deng, X and Xiao, S and Pan, Z},
title = {Comparative transcriptome analysis of Poncirus trifoliata identifies a core set of genes involved in arbuscular mycorrhizal symbiosis.},
journal = {Journal of experimental botany},
volume = {69},
number = {21},
pages = {5255-5264},
doi = {10.1093/jxb/ery283},
pmid = {30312435},
issn = {1460-2431},
abstract = {The perennial woody plants of citrus are one of the most important fruit crops in the world and largely depends on arbuscular mycorrhizal symbiosis (AMS) to obtain essential nutrients from soil. However, the molecular aspects of AMS in citrus and perennial woody plants in general have largely been understudied. We used RNA-sequencing to identify differentially expressed genes in roots of Poncirus trifoliata upon mycorrhization by the AM fungus Glomus versiforme and evaluated their conservation by comparative transcriptome analyses with four herbaceous model plants. We identified 282 differentially expressed genes in P. trifoliata, including orthologs of 21 genes with characterized roles in AMS and 83 genes that are considered to be conserved in AM-host plants. Comparative transcriptome analysis revealed a 'core set' of 156 genes from P. trifoliata whose orthologous genes from at least three of the five species also exhibited similar transcriptional changes during AMS. Functional analysis of one of these conserved AM-induced genes, a 3-keto-acyl-ACP reductase (FatG) involved in fatty acid biosynthesis, confirmed its involvement in AMS in Medicago truncatula. Our results identify a core transcriptional program for AMS that is largely conserved between P. trifoliata and other plants. The comparative transcriptomics approach adds to previous phylogenomics studies to identify conserved genes required for AMS.},
}
@article {pmid30312413,
year = {2018},
author = {Van Geel, M and Yu, K and Ceulemans, T and Peeters, G and van Acker, K and Geerts, W and Ramos, MA and Serafim, C and Kastendeuch, P and Najjar, G and Ameglio, T and Ngao, J and Saudreau, M and Waud, M and Lievens, B and Castro, PM and Somers, B and Honnay, O},
title = {Variation in ectomycorrhizal fungal communities associated with Silver linden (Tilia tomentosa) within and across urban areas.},
journal = {FEMS microbiology ecology},
volume = {94},
number = {12},
pages = {},
doi = {10.1093/femsec/fiy207},
pmid = {30312413},
issn = {1574-6941},
abstract = {Trees in urban areas face harsh environmental conditions. Ectomycorrhizal fungi (EcM) form a symbiosis with many tree species and provide a range of benefits to their host through their extraradical hyphal network. Although our understanding of the environmental drivers and large scale geographical variation of EcM communities in natural ecosystems is growing, our knowledge of EcM communities within and across urban areas is still limited. Here, we characterized EcM communities using Illumina miseq sequencing on 175 root samples of the urban tree Tilia tomentosa from three European cities, namely Leuven (Belgium), Strasbourg (France) and Porto (Portugal). We found strong differences in EcM richness and community composition between cities. Soil acidity, organic matter and moisture content were significantly associated with EcM community composition. In agreement, the explained variability in EcM communities was mostly attributed to general soil characteristics, whereas very little variation was explained by city and heavy metal pollution. Overall, our results suggest that EcM communities in urban areas are significantly associated with soil characteristics, while heavy metal pollution and biogeography had little or no impact. These findings deliver new insights into EcM distribution patterns in urban areas and contribute to specific inoculation strategies to improve urban tree vitality.},
}
@article {pmid30312395,
year = {2019},
author = {Navrátilová, D and Tláskalová, P and Kohout, P and Drevojan, P and Fajmon, K and Chytrý, M and Baldrian, P},
title = {Diversity of fungi and bacteria in species-rich grasslands increases with plant diversity in shoots but not in roots and soil.},
journal = {FEMS microbiology ecology},
volume = {95},
number = {1},
pages = {},
doi = {10.1093/femsec/fiy208},
pmid = {30312395},
issn = {1574-6941},
abstract = {Microbial communities in roots and shoots of plants and in soil are important for plant growth and health and take part in important ecosystem processes. Therefore, understanding the factors that affect their diversity is important. We have analyzed fungal and bacterial communities associated with plant shoots, roots and soil over a 1 km2 area in a semi-natural temperate grassland with 1-43 plant species per 0.1 m2, to describe the relationships between plant and microbial diversity and to identify the drivers of bacterial and fungal community composition. Microbial community composition differed between shoots, roots and soil. While both fungal and bacterial species richness in shoots increased with plant species richness, no correlation was found between plant and microbial diversity in roots and soil. Chemistry was a significant predictor of bacterial and fungal community composition in soil as was also the spatial location of the sampled site. In this species-rich grassland, the effects of plants on the microbiome composition seemed to be restricted to the shoot-associated taxa; in contrast, the microbiomes of roots or soil were not affected. The results support our hypothesis that the effect of plants on the microbiome composition decreases from shoots to roots and soil.},
}
@article {pmid30311675,
year = {2018},
author = {Leftwich, PT and Hutchings, MI and Chapman, T},
title = {Diet, Gut Microbes and Host Mate Choice: Understanding the significance of microbiome effects on host mate choice requires a case by case evaluation.},
journal = {BioEssays : news and reviews in molecular, cellular and developmental biology},
volume = {40},
number = {12},
pages = {e1800053},
doi = {10.1002/bies.201800053},
pmid = {30311675},
issn = {1521-1878},
support = {BB/K000489/1//Biotechnology and Biological Sciences Research Council/United Kingdom ; },
abstract = {All organisms live in close association with microbes. However, not all such associations are meaningful in an evolutionary context. Current debate concerns whether hosts and microbes are best described as communities of individuals or as holobionts (selective units of hosts plus their microbes). Recent reports that assortative mating of hosts by diet can be mediated by commensal gut microbes have attracted interest as a potential route to host reproductive isolation (RI). Here, the authors discuss logical problems with this line of argument. The authors briefly review how microbes can affect host mating preferences and evaluate recent findings from fruitflies. Endosymbionts can potentially influence host RI given stable and recurrent co-association of hosts and microbes over evolutionary time. However, observations of co-occurrence of microbes and hosts are ripe for misinterpretation and such associations will rarely represent a meaningful holobiont. A framework in which hosts and their microbes are independent evolutionary units provides the only satisfactory explanation for the observed range of effects and associations.},
}
@article {pmid30311476,
year = {2018},
author = {Hasid, R and Jaya Arma, M and Nurmas, A},
title = {Existence Arbuscula Mycorrhiza and Its Application Effect to Several Variety of Corn Plant (&lt;I&gt;Zeal mays &lt;/I&gt; L.) in Marginal Dry Land.},
journal = {Pakistan journal of biological sciences : PJBS},
volume = {21},
number = {4},
pages = {199-204},
doi = {10.3923/pjbs.2018.199.204},
pmid = {30311476},
issn = {1028-8880},
abstract = {BACKGROUND AND OBJECTIVE: Arbuscula mycorrhiza (AM) have a very large function in symbiosis with plant roots, it's very important to be studied further because AM utilization is an alternative solution to improve the yield of corn plant in poor land. Until now the productivity of corn plant, especially in Southeast Sulawesi, Indonesia is lower than it's genetic potential, one of the causes is the cultivation of many plant done in sub optimal land with low technology applications especially the use of organic and biological fertilizer very low. This study aimed to observe the presence of AM and evaluate the growth and productivity of corn plant that AM inoculated.<br><br>MATERIALS AND METHODS: The study consisted two series of experiments, namely (1) Existence arbuscula mycorrhiza in rhizosphere of dominant weed (bladygrass) in dry land in Kendari, Southeast Sulawesi, Indonesia, was observed descriptively, (2) Effect of arbuscula mycorrhiza to several variety of corn plant (Zea mays L.) in Marginal dry land. The experiment was arranged based Randomized Block Design (RBD) consisted of eight treatments corn variety.<br><br>RESULTS: The results showed that spore populations were found in rhizosphere of dominant weed was 792-901 spores 100 g-1 soil, 70-90% roots infection. Some genera found are Glomus, Gigasphora, Acaulospora, Entrophospora, Scutellospora. Symbiosis effect of arbuscula mycorrhiza with plant growth indicates that Phosphorus uptake was highest in Batu Putih variety. However the highest in yield was show in Dana variety. Compared with the lowest production, the production difference was higher in Dana 47.70%.<br><br>CONCLUSION: Existence of arbuscula mycorrhiza in dominant weed rhizosphere in dry land is very high. The response of various varieties of maize plants to arbuscula mycorrhiza indicates that local varieties have a higher adaptability compared with introduction varieties.},
}
@article {pmid30306463,
year = {2018},
author = {Hocher, V and Ngom, M and Carré-Mlouka, A and Tisseyre, P and Gherbi, H and Svistoonoff, S},
title = {Signalling in actinorhizal root nodule symbioses.},
journal = {Antonie van Leeuwenhoek},
volume = {},
number = {},
pages = {},
doi = {10.1007/s10482-018-1182-x},
pmid = {30306463},
issn = {1572-9699},
support = {2015-67014-22849//National Institute of Food and Agriculture/ ; ANR-12-BSV7-0007-01//Agence Nationale de la Recherche/ ; },
abstract = {Plants able to establish a nitrogen-fixing root nodule symbiosis with the actinobacterium Frankia are called actinorhizal. These interactions lead to the formation of new root organs, called actinorhizal nodules, where the bacteria are hosted intracellularly and fix atmospheric nitrogen thus providing the plant with an almost unlimited source of nitrogen for its nutrition. Like other symbiotic interactions, actinorhizal nodulation involves elaborate signalling between both partners of the symbiosis, leading to specific recognition between the plant and its compatible microbial partner, its accommodation inside plant cells and the development of functional root nodules. Actinorhizal nodulation shares many features with rhizobial nodulation but our knowledge on the molecular mechanisms involved in actinorhizal nodulation remains very scarce. However recent technical achievements for several actinorhizal species are allowing major discoveries in this field. In this review, we provide an outline on signalling molecules involved at different stages of actinorhizal nodule formation and the corresponding signalling pathways and gene networks.},
}
@article {pmid30305437,
year = {2018},
author = {Rimington, WR and Pressel, S and Duckett, JG and Field, KJ and Read, DJ and Bidartondo, MI},
title = {Ancient plants with ancient fungi: liverworts associate with early-diverging arbuscular mycorrhizal fungi.},
journal = {Proceedings. Biological sciences},
volume = {285},
number = {1888},
pages = {},
doi = {10.1098/rspb.2018.1600},
pmid = {30305437},
issn = {1471-2954},
abstract = {Arbuscular mycorrhizas are widespread in land plants including liverworts, some of the closest living relatives of the first plants to colonize land 500 million years ago (MYA). Previous investigations reported near-exclusive colonization of liverworts by the most recently evolved arbuscular mycorrhizal fungi, the Glomeraceae, indicating a recent acquisition from flowering plants at odds with the widely held notion that arbuscular mycorrhizal-like associations in liverworts represent the ancestral symbiotic condition in land plants. We performed an analysis of symbiotic fungi in 674 globally collected liverworts using molecular phylogenetics and electron microscopy. Here, we show every order of arbuscular mycorrhizal fungi colonizes early-diverging liverworts, with non-Glomeraceae being at least 10 times more common than in flowering plants. Arbuscular mycorrhizal fungi in liverworts and other ancient plant lineages (hornworts, lycopods, and ferns) were delimited into 58 taxa and 36 singletons, of which at least 43 are novel and specific to liverworts. The discovery that early plant lineages are colonized by early-diverging fungi supports the hypothesis that arbuscular mycorrhizas are an ancestral symbiosis for all land plants.},
}
@article {pmid30305320,
year = {2018},
author = {Lang, C and Barnett, MJ and Fisher, RF and Smith, LS and Diodati, ME and Long, SR},
title = {Most Sinorhizobium meliloti Extracytoplasmic Function Sigma Factors Control Accessory Functions.},
journal = {mSphere},
volume = {3},
number = {5},
pages = {},
doi = {10.1128/mSphereDirect.00454-18},
pmid = {30305320},
issn = {2379-5042},
support = {R01 GM093628/GM/NIGMS NIH HHS/United States ; },
abstract = {Bacteria must sense alterations in their environment and respond with changes in function and/or structure in order to cope. Extracytoplasmic function sigma factors (ECF σs) modulate transcription in response to cellular and environmental signals. The symbiotic nitrogen-fixing alphaproteobacterium Sinorhizobium meliloti carries genes for 11 ECF-like σs (RpoE1 to -E10 and FecI). We hypothesized that some of these play a role in mediating the interaction between the bacterium and its plant symbiotic partner. The bacterium senses changes in its immediate environment as it establishes contact with the plant root, initiates invasion of the plant as the root nodule is formed, traverses several root cell layers, and enters plant cortical cells via endocytosis. We used genetics, transcriptomics, and functionality to characterize the entire S. meliloti cohort of ECF σs. We discovered new targets for individual σs, confirmed others by overexpressing individual ECF σs, and identified or confirmed putative promoter motifs for nine of them. We constructed precise deletions of each ECF σ gene and its demonstrated or putative anti-σ gene and also a strain in which all 11 ECF σ and anti-σ genes were deleted. This all-ECF σ deletion strain showed no major defects in free-living growth, in Biolog Phenotype MicroArray assays, or in response to multiple stresses. None of the ECF σs were required for symbiosis on the host plants Medicago sativa and Medicago truncatula: the strain deleted for all ECF σ and anti-σ genes was symbiotically normal.IMPORTANCE Fixed (reduced) soil nitrogen plays a critical role in soil fertility and successful food growth. Much soil fertility relies on symbiotic nitrogen fixation: the bacterial partner infects the host plant roots and reduces atmospheric dinitrogen in exchange for host metabolic fuel, a process that involves complex interactions between the partners mediated by changes in gene expression in each partner. Here we test the roles of a family of 11 extracytoplasmic function (ECF) gene regulatory proteins (sigma factors [σs]) that interact with RNA polymerase to determine if they play a significant role in establishing a nitrogen-fixing symbiosis or in responding to various stresses, including cell envelope stress. We discovered that symbiotic nitrogen fixation occurs even when all 11 of these regulatory genes are deleted, that most ECF sigma factors control accessory functions, and that none of the ECF sigma factors are required to survive envelope stress.},
}
@article {pmid30305166,
year = {2018},
author = {Guyomar, C and Legeai, F and Jousselin, E and Mougel, C and Lemaitre, C and Simon, JC},
title = {Multi-scale characterization of symbiont diversity in the pea aphid complex through metagenomic approaches.},
journal = {Microbiome},
volume = {6},
number = {1},
pages = {181},
doi = {10.1186/s40168-018-0562-9},
pmid = {30305166},
issn = {2049-2618},
abstract = {BACKGROUND: Most metazoans are involved in durable relationships with microbes which can take several forms, from mutualism to parasitism. The advances of NGS technologies and bioinformatics tools have opened opportunities to shed light on the diversity of microbial communities and to give some insights into the functions they perform in a broad array of hosts. The pea aphid is a model system for the study of insect-bacteria symbiosis. It is organized in a complex of biotypes, each adapted to specific host plants. It harbors both an obligatory symbiont supplying key nutrients and several facultative symbionts bringing additional functions to the host, such as protection against biotic and abiotic stresses. However, little is known on how the symbiont genomic diversity is structured at different scales: across host biotypes, among individuals of the same biotype, or within individual aphids, which limits our understanding on how these multi-partner symbioses evolve and interact.<br><br>RESULTS: We present a framework well adapted to the study of genomic diversity and evolutionary dynamics of the pea aphid holobiont from metagenomic read sets, based on mapping to reference genomes and whole genome variant calling. Our results revealed that the pea aphid microbiota is dominated by a few heritable bacterial symbionts reported in earlier works, with no discovery of new microbial associates. However, we detected a large and heterogeneous genotypic diversity associated with the different symbionts of the pea aphid. Partitioning analysis showed that this fine resolution diversity is distributed across the three considered scales. Phylogenetic analyses highlighted frequent horizontal transfers of facultative symbionts between host lineages, indicative of flexible associations between the pea aphid and its microbiota. However, the evolutionary dynamics of symbiotic associations strongly varied depending on the symbiont, reflecting different histories and possible constraints. In addition, at the intra-host scale, we showed that different symbiont strains may coexist inside the same aphid host.<br><br>CONCLUSIONS: We present a methodological framework for the detailed analysis of NGS data from microbial communities of moderate complexity and gave major insights into the extent of diversity in pea aphid-symbiont associations and the range of evolutionary trajectories they could take.},
}
@article {pmid30305028,
year = {2018},
author = {Osti, JF and Rodrigues, A},
title = {Escovopsioides as a fungal antagonist of the fungus cultivated by leafcutter ants.},
journal = {BMC microbiology},
volume = {18},
number = {1},
pages = {130},
doi = {10.1186/s12866-018-1265-x},
pmid = {30305028},
issn = {1471-2180},
support = {2014/24298-1//Fundação de Amparo à Pesquisa do Estado de São Paulo/ ; },
abstract = {BACKGROUND: Fungus gardens of fungus-growing (attine) ants harbor complex microbiomes in addition to the mutualistic fungus they cultivate for food. Fungi in the genus Escovopsioides were recently described as members of this microbiome but their role in the ant-fungus symbiosis is poorly known. In this study, we assessed the phylogenetic diversity of 21 Escovopsioides isolates obtained from fungus gardens of leafcutter ants (genera Atta and Acromyrmex) and non-leafcutter ants (genera Trachymyrmex and Apterostigma) sampled from several regions in Brazil.<br><br>RESULTS: Regardless of the sample locality or ant genera, phylogenetic analysis showed low genetic diversity among the 20 Escovopsisoides isolates examined, which prompted the identification as Escovopsioides nivea (the only described species in the genus). In contrast, one Escovopsioides isolate obtained from a fungus garden of Apterostigma megacephala was considered a new phylogenetic species. Dual-culture plate assays showed that Escovopsioides isolates inhibited the mycelium growth of Leucoagaricus gongylophorus, the mutualistic fungus cultivated by somes species of leafcutter ants. In addition, Escovopsioides growth experiments in fungus gardens with and without ant workers showed this fungus is detrimental to the ant-fungus symbiosis.<br><br>CONCLUSIONS: Here, we provide clues for the antagonism of Escovopsioides towards the mutualistic fungus of leafcutter ants.},
}
@article {pmid30304706,
year = {2018},
author = {Santiago, R and Martins, MCB and Vilaça, MD and Barros, LFB and Nascimento, T and Silva, NHD and Falcão, EPS and Legaz, ME and Vicente, C and Pereira, EC},
title = {Phytochemical and biological evaluation of metabolites produced by alginate-immobilized Bionts isolated from the lichen Cladonia substellata vain.},
journal = {Fitoterapia},
volume = {131},
number = {},
pages = {23-34},
doi = {10.1016/j.fitote.2018.10.001},
pmid = {30304706},
issn = {1873-6971},
abstract = {In this work, new biotechnological procedures have been optimized on the basis of immobilization in alginate of bionts isolated from the lichen C. substellata. From these immobilizates, soluble and biologically active phenolics can be obtained. During bionts-immobilization, stictic, norstictic and usnic acids were secreted to the medium. The amount produced of each of them differed depending on the immobilization time, the precursor supplied and the type of biont used. Greater amounts of stictic acid were detected and maintained over time in all bioreactors. The opposite occurs in non-immobilized thallus. Virtually, all lichen phenols exhibit antioxidant activity to a greater or lesser degree, so that the antioxidant capacity of stictic acid (82.13% oxidation inhibition) was tested. The soluble extract of immobilized algae co-incubated in sodium acetate with fungal hyphae contained carbohydrates and exhibited a potent antioxidant capacity after 13 days of immobilization (94.87%). Therefore, attempts have been made to relate both parameters. On the other hand, the growth of Staphylococcus aureus, Escherichia coli and Klebsiella pneumoniae was inhibited by phenolic compounds produced by immobilizates, although the organic extract of the whole lichen showed the highest activity due to a possible synergy with other indeterminate compounds. Thus, C. substellata immobilized bionts are a potential source of different natural antioxidant and antimicrobial compounds.},
}
@article {pmid30304508,
year = {2018},
author = {Li, Y and Ruan, Y and Kasson, MT and Stanley, EL and Gillett, CPDT and Johnson, AJ and Zhang, M and Hulcr, J},
title = {Structure of the Ambrosia Beetle (Coleoptera: Curculionidae) Mycangia Revealed Through Micro-Computed Tomography.},
journal = {Journal of insect science (Online)},
volume = {18},
number = {5},
pages = {},
doi = {10.1093/jisesa/iey096},
pmid = {30304508},
issn = {1536-2442},
mesh = {Animal Structures/*anatomy &amp; histology ; Animals ; Fungi/physiology ; Paraffin Embedding/*methods ; Symbiosis ; Tomography/*methods ; Weevils/*anatomy &amp; histology/microbiology/physiology ; X-Ray Microtomography/methods ; },
abstract = {Ambrosia beetles (Coleoptera: Curculionidae: Scolytinae and Platypodinae) rely on a symbiosis with fungi for their nutrition. Symbiotic fungi are preserved and transported in specialized storage structures called mycangia. Although pivotal in the symbiosis, mycangia have been notoriously difficult to study, given their minute size and membranous structure. We compared the application of novel visualization methods for the study of mycangia, namely micro-computed tomography (micro-CT) and laser ablation tomography (LATscan) with traditional paraffin sectioning. Micro-CT scanning has shown the greatest promise in new organ discovery, while sectioning remains the only method with sufficient resolution for cellular visualization. All three common types of mycangia (oral, mesonotal, and pronotal) were successfully visualized and presented for different species of ambrosia beetles: Ambrosiodmus minor (Stebbing) 1909, Euplatypus compositus (Say) 1823, Premnobius cavipennis Eichhoff 1878, Scolytoplatypus raja Blandford 1893, Xylosandrus crassiusculus (Motschulsky) 1866 and X. amputatus (Blandford) 1894. A reconstruction of the mycangium and the surrounding musculature in X. amputatus is also presented. The advantages of micro-CT compared to the previously commonly used microtome sectioning include the easy visualization and recording of three-dimensional structures, their position in reference to other internal structures, the ability to distinguish natural aberrations from technical artifacts, and the unprecedented visualizations of the anatomic context of mycangia enabled by the integrated software.},
}
@article {pmid30301859,
year = {2018},
author = {Wiles, TJ and Wall, ES and Schlomann, BH and Hay, EA and Parthasarathy, R and Guillemin, K},
title = {Modernized Tools for Streamlined Genetic Manipulation and Comparative Study of Wild and Diverse Proteobacterial Lineages.},
journal = {mBio},
volume = {9},
number = {5},
pages = {},
doi = {10.1128/mBio.01877-18},
pmid = {30301859},
issn = {2150-7511},
support = {F32 AI112094/AI/NIAID NIH HHS/United States ; T32 GM007759/GM/NIGMS NIH HHS/United States ; },
abstract = {Correlating the presence of bacteria and the genes they carry with aspects of plant and animal biology is rapidly outpacing the functional characterization of naturally occurring symbioses. A major barrier to mechanistic studies is the lack of tools for the efficient genetic manipulation of wild and diverse bacterial isolates. To address the need for improved molecular tools, we used a collection of proteobacterial isolates native to the zebrafish intestinal microbiota as a testbed to construct a series of modernized vectors that expedite genetic knock-in and knockout procedures across lineages. The innovations that we introduce enhance the flexibility of conventional genetic techniques, making it easier to manipulate many different bacterial isolates with a single set of tools. We developed alternative strategies for domestication-free conjugation, designed plasmids with customizable features, and streamlined allelic exchange using visual markers of homologous recombination. We demonstrate the potential of these tools through a comparative study of bacterial behavior within the zebrafish intestine. Live imaging of fluorescently tagged isolates revealed a spectrum of distinct population structures that differ in their biogeography and dominant growth mode (i.e., planktonic versus aggregated). Most striking, we observed divergent genotype-phenotype relationships: several isolates that are predicted by genomic analysis and in vitro assays to be capable of flagellar motility do not display this trait within living hosts. Together, the tools generated in this work provide a new resource for the functional characterization of wild and diverse bacterial lineages that will help speed the research pipeline from sequencing-based correlations to mechanistic underpinnings.IMPORTANCE A great challenge in microbiota research is the immense diversity of symbiotic bacteria with the capacity to impact the lives of plants and animals. Moving beyond correlative DNA sequencing-based studies to define the cellular and molecular mechanisms by which symbiotic bacteria influence the biology of their hosts is stalling because genetic manipulation of new and uncharacterized bacterial isolates remains slow and difficult with current genetic tools. Moreover, developing tools de novo is an arduous and time-consuming task and thus represents a significant barrier to progress. To address this problem, we developed a suite of engineering vectors that streamline conventional genetic techniques by improving postconjugation counterselection, modularity, and allelic exchange. Our modernized tools and step-by-step protocols will empower researchers to investigate the inner workings of both established and newly emerging models of bacterial symbiosis.},
}
@article {pmid30301849,
year = {2018},
author = {Hernandez-Agreda, A and Leggat, W and Bongaerts, P and Herrera, C and Ainsworth, TD},
title = {Rethinking the Coral Microbiome: Simplicity Exists within a Diverse Microbial Biosphere.},
journal = {mBio},
volume = {9},
number = {5},
pages = {},
doi = {10.1128/mBio.00812-18},
pmid = {30301849},
issn = {2150-7511},
abstract = {Studies of the coral microbiome predominantly characterize the microbial community of the host species as a collective, rather than that of the individual. This ecological perspective on the coral microbiome has led to the conclusion that the coral holobiont is the most diverse microbial biosphere studied thus far. However, investigating the microbiome of the individual, rather than that of the species, highlights common and conserved community attributes which can provide insights into the significance of microbial associations to the host. Here, we show there are consistent characteristics between individuals in the proposed three components of the coral microbiome (i.e., &quot;environmentally responsive community,&quot; &quot;resident or individual microbiome,&quot; and &quot;core microbiome&quot;). We found that the resident microbiome of a photoendosymbiotic coral harbored <3% (∼605 phylotypes) of the 16S rRNA phylotypes associated with all investigated individuals of that species (&quot;species-specific microbiome&quot;) (∼21,654 phylotypes; individuals from Pachyseris speciosa [n = 123], Mycedium elephantotus [n = 95], and Acropora aculeus [n = 91] from 10 reef locations). The remaining bacterial phylotypes (>96%) (environmentally responsive community) of the species-specific microbiome were in fact not found in association with the majority of individuals of the species. Only 0.1% (∼21 phylotypes) of the species-specific microbiome of each species was shared among all individuals of the species (core microbiome), equating to ∼3.4% of the resident microbiome. We found taxonomic redundancy and consistent patterns of composition, structure, and taxonomic breadth across individual microbiomes from the three coral species. Our results demonstrate that the coral microbiome is structured at the individual level.IMPORTANCE We propose that the coral holobiont should be conceptualized as a diverse transient microbial community that is responsive to the surrounding environment and encompasses a simple, redundant, resident microbiome and a small conserved core microbiome. Most importantly, we show that the coral microbiome is comparable to the microbiomes of other organisms studied thus far. Accurately characterizing the coral-microbe interactions provides an important baseline from which the functional roles and the functional niches within which microbes reside can be deciphered.},
}
@article {pmid30301104,
year = {2018},
author = {Okubo, N and Takahashi, S and Nakano, Y},
title = {Microplastics disturb the anthozoan-algae symbiotic relationship.},
journal = {Marine pollution bulletin},
volume = {135},
number = {},
pages = {83-89},
doi = {10.1016/j.marpolbul.2018.07.016},
pmid = {30301104},
issn = {1879-3363},
abstract = {World production of plastic has dramatically increased from the 1950's and now it reaches approximately 311 million tons per year. The resulting accumulation of small plastic detritus less than 5 mm in size, termed &quot;microplastics&quot;, has started threatening the life cycles of marine organisms. Here we show the first evidence that microplastics disturb the initiation of symbiotic relationships in anthozoan-algae symbiosis. We found in both the aposymbiotic sea-anemone Aiptasia sp. and the coral Favites chinensis that the infectivity of symbiotic algae into the host is severely suppressed by microspheres fed either directly or indirectly through microsphere-fed Artemia sp. Similar trends were seen when microplastics collected from commercial facewash were used instead of microspheres. Therefore, ongoing accumulation of microplastics in the ocean might disturb the healthy anthozoan-algae symbiotic relationships, which are cornerstones of the biologically enriched coral reef ecosystem.},
}
@article {pmid30299536,
year = {2018},
author = {Dovrat, G and Sheffer, E},
title = {Symbiotic dinitrogen fixation is seasonal and strongly regulated in water-limited environments.},
journal = {The New phytologist},
volume = {},
number = {},
pages = {},
doi = {10.1111/nph.15526},
pmid = {30299536},
issn = {1469-8137},
support = {508/16//Israel Science Foundation/ ; },
abstract = {Plants, especially perennials, growing in drylands and seasonally dry ecosystems are uniquely adapted to dry conditions. Legume shrubs and trees, capable of symbiotic dinitrogen (N2) fixation, often dominate in drylands. However, the strategies that allow symbiotic fixation in these ecosystems, and their influence on the nitrogen cycle, are largely unresolved. We evaluated the climatic, biogeochemical and ontogenetic factors influencing nitrogen fixation in an abundant Mediterranean legume shrub, Calicotome villosa. We measured nodulation, fixation rate, nitrogen allocation and soil biogeochemistry in three field sites over a full year. A controlled experiment evaluated differences in plant regulation of fixation as a function of soil nutrient availability and seedling and adult developmental stages. We found a strong seasonal pattern, shifting between high fixation rates during the rainy season at flowering and seed-set times to almost none in the rainless season. Under controlled conditions, plants downregulated fixation in response to soil nitrogen availability, but this response was stronger in seedlings than in adult shrubs. Finally, we did not find elevated soil nitrogen under N2 -fixing shrubs. We conclude that seasonal nitrogen fixation, regulation of fixation, and nitrogen conservation are key adaptations influencing the dominance of dryland legumes in the community, with broader consequences on the ecosystem nitrogen cycle.},
}
@article {pmid30296049,
year = {2018},
author = {Palmer, AG and Senechal, AC and Haire, TC and Mehta, NP and Valiquette, SD and Blackwell, HE},
title = {Selection of Appropriate Autoinducer Analogues for the Modulation of Quorum Sensing at the Host-Bacterium Interface.},
journal = {ACS chemical biology},
volume = {13},
number = {11},
pages = {3115-3122},
doi = {10.1021/acschembio.8b00676},
pmid = {30296049},
issn = {1554-8937},
support = {R01 GM109403/GM/NIGMS NIH HHS/United States ; T32 GM008505/GM/NIGMS NIH HHS/United States ; },
abstract = {Bacteria regulate a variety of phenotypes in response to their population density using quorum sensing (QS). This phenomenon is regulated by small molecule or peptide signals, the best characterized of which are the N-acyl l-homoserine lactones (AHLs) utilized by Gram-negative bacteria. As many QS-controlled phenotypes, notably pathogenicity and symbiosis, can profoundly impact host eukaryotes, there is significant interest in developing methods for modulating QS signaling and either ameliorating or augmenting these phenotypes. One strategy has been the use of non-native AHL analogues to agonize or antagonize specific AHL receptors. This approach is complicated, however, by the potential for prospective hosts to respond to both native AHLs and synthetic analogues. Accordingly, identifying AHL analogues with little or no activity toward eukaryotes is important in developing QS modulation as a strategy for the regulation of prokaryotic behaviors. Herein, we utilize the model plant Arabidopsis thaliana to characterize eukaryotic responses to a variety of synthetic AHL analogues to identify structural elements of existing scaffolds that may elicit responses in prospective hosts. Our results indicate that, while many of these compounds have no discernible effect on A. thaliana, some elicit strong phenotypes similar to those produced by auxin, a hormone involved in almost all aspects of plant development. We outline concentrations and chemical scaffolds that are ideal for deployment on plant hosts for the regulation of QS. This approach should be exportable to other eukaryotes for the selection of optimal AHL tools for the study of QS at the host-microbe interface.},
}
@article {pmid30294583,
year = {2018},
author = {Kalra, S and Jena, BN and Yeravdekar, R},
title = {Emotional and Psychological Needs of People with Diabetes.},
journal = {Indian journal of endocrinology and metabolism},
volume = {22},
number = {5},
pages = {696-704},
doi = {10.4103/ijem.IJEM_579_17},
pmid = {30294583},
issn = {2230-8210},
abstract = {Diabetes is a chronic metabolic disorder that impacts physical, social and mental including psychological well-being of people living with it. Additionally, psychosocial problems that are most common in diabetes patients often result in serious negative impact on patient's well-being and social life, if left un-addressed. Addressing such psychosocial aspects including cognitive, emotional, behavioral and social factors in the treatment interventions would help overcome the psychological barriers, associated with adherence and self-care for diabetes; the latter being the ultimate goal of management of patients with diabetes. While ample literature on self-management and psychological interventions for diabetes is available, there is limited information on the impact of psychological response and unmanaged emotional distresses on overall health. The current review therefore examines the emotional, psychological needs of the patients with diabetes and emphasizes the role of diabetologist, mental health professionals including clinical psychologists to mitigate the problems faced by these patients. Search was performed using a combination of keywords that cover all relevant terminology for diabetes and associated emotional distress. The psychological reactions experienced by the patient upon diagnosis of diabetes have been reviewed in this article with a focus on typical emotional distress at different levels. Identifying and supporting patients with psychosocial problems early in the course of diabetes may promote psychosocial well-being and improve their ability to adjust or take adequate responsibility in diabetes self-management - the utopian state dreamt of by all diabetologists !.},
}
@article {pmid30292683,
year = {2018},
author = {Jiang, Y and Xie, Q and Wang, W and Yang, J and Zhang, X and Yu, N and Zhou, Y and Wang, E},
title = {Medicago AP2-Domain Transcription Factor WRI5a Is a Master Regulator of Lipid Biosynthesis and Transfer during Mycorrhizal Symbiosis.},
journal = {Molecular plant},
volume = {11},
number = {11},
pages = {1344-1359},
doi = {10.1016/j.molp.2018.09.006},
pmid = {30292683},
issn = {1752-9867},
abstract = {Most land plants have evolved a mutualistic symbiosis with arbuscular mycorrhiza (AM) fungi that improve nutrient acquisition from the soil. In return, up to 20% of host plant photosynthate is transferred to the mycorrhizal fungus in the form of lipids and sugar. Nutrient exchange must be regulated by both partners in order to maintain a reliable symbiotic relationship. However, the mechanisms underlying the regulation of lipid transfer from the plant to the AM fungus remain elusive. Here, we show that the Medicago truncatula AP2/EREBP transcription factor WRI5a, and likely its two homologs WRI5b/Erf1 and WRI5c, are master regulators of AM symbiosis controlling lipid transfer and periarbuscular membrane formation. We found that WRI5a binds AW-box cis-regulatory elements in the promoters of M. truncatula STR, which encodes a periarbuscular membrane-localized ABC transporter required for lipid transfer from the plant to the AM fungus, and MtPT4, which encodes a phosphate transporter required for phosphate transfer from the AM fungus to the plant. The hairy roots of the M. truncatula wri5a mutant and RNAi composite plants displayed impaired arbuscule formation, whereas overexpression of WRI5a resulted in enhanced expression of STR and MtPT4, suggesting that WRI5a regulates bidirectional symbiotic nutrient exchange. Moreover, we found that WRI5a and RAM1 (Required for Arbuscular Mycorrhization symbiosis 1), which encodes a GRAS-domain transcription factor, regulate each other at the transcriptional level, forming a positive feedback loop for regulating AM symbiosis. Collectively, our data suggest a role for WRI5a in controlling bidirectional nutrient exchange and periarbuscular membrane formation via the regulation of genes involved in the biosynthesis of fatty acids and phosphate uptake in arbuscule-containing cells.},
}
@article {pmid30289375,
year = {2018},
author = {Becquer, A and Garcia, K and Plassard, C},
title = {HcPT1.2 participates in Pi acquisition in Hebeloma cylindrosporum external hyphae of ectomycorrhizas under high and low phosphate conditions.},
journal = {Plant signaling &amp; behavior},
volume = {13},
number = {10},
pages = {e1525997},
doi = {10.1080/15592324.2018.1525997},
pmid = {30289375},
issn = {1559-2324},
abstract = {Ectomycorrhizal fungi improve tree phosphorus nutrition through transporters specifically localized at soil-hyphae and symbiotic interfaces. In the model symbiosis between the fungus Hebeloma cylindrosporum and the maritime pine (Pinus pinaster), several transporters possibly involved in phosphate fluxes were identified, including three H+:Pi transporters. Among these three, we recently unraveled the function of one of them, named HcPT2, in both pure culture and symbiotic interaction with P. pinaster. Here we investigated the transporter named HcPT1.2, by analyzing inorganic phosphate transport ability in a yeast complementation assay, assessing its expression in the fungus associated or not with the plant, and immunolocalizing the proteins in ectomycorrhizas. We also evaluated the effect of external Pi concentration on expression and localization of HcPT1.2. Our results revealed that HcPT1.2 is involved in Pi acquisition by H. cylindrosporum mycelium, irrespective of the external Pi concentrations.},
}
@article {pmid30286722,
year = {2018},
author = {Mancini, MV and Damiani, C and Accoti, A and Tallarita, M and Nunzi, E and Cappelli, A and Bozic, J and Catanzani, R and Rossi, P and Valzano, M and Serrao, A and Ricci, I and Spaccapelo, R and Favia, G},
title = {Estimating bacteria diversity in different organs of nine species of mosquito by next generation sequencing.},
journal = {BMC microbiology},
volume = {18},
number = {1},
pages = {126},
doi = {10.1186/s12866-018-1266-9},
pmid = {30286722},
issn = {1471-2180},
support = {Prin 2012-2012T85B3R//Ministero dell'Istruzione, dell'Università e della Ricerca/ ; PRIN 2015-JXC3JF//Ministero dell'Istruzione, dell'Università e della Ricerca/ ; FAR2015//Università di Camerino/ ; },
abstract = {BACKGROUND: Symbiosis in insects is accumulating significant amount of studies: the description of a wide array of mutualistic associations across the evolutionary history of insects suggests that resident microbiota acts as a driving force by affecting several aspects of hosts biology. Among arthropods, mosquito midgut microbiota has been largely investigated, providing crucial insights on the role and implications of host-symbiont relationships. However, limited amount of studies addressed their efforts on the investigation of microbiota colonizing salivary glands and reproductive tracts, crucial organs for pathogen invasion and vertical transmission of symbiotic microorganisms. Using 16S rRNA gene sequencing-based approach, we analysed the microbiota of gut, salivary glands and reproductive tracts of several mosquito species, representing some of the main vectors of diseases, aiming at describing the dynamics of bacterial communities within the individual.<br><br>RESULTS: We identified a shared core microbiota between different mosquito species, although interesting inter- and intra-species differences were detected. Additionally, our results showed deep divergences between genera, underlining microbiota specificity and adaptation to their host.<br><br>CONCLUSIONS: The comprehensive landscape of the bacterial microbiota components may ultimately provide crucial insights and novel targets for possible application of symbionts in innovative strategies for the control of vector borne diseases, globally named Symbiotic Control (SC), and suggesting that the holobiont of different mosquito species may significantly vary. Moreover, mosquito species are characterized by distinctive microbiota in different organs, likely reflecting different functions and/or adaptation processes.},
}
@article {pmid30286318,
year = {2018},
author = {Higuchi, R and Song, C and Hoshina, R and Suzaki, T},
title = {Endosymbiosis-related changes in ultrastructure and chemical composition of Chlorella variabilis (Archaeplastida, Chlorophyta) cell wall in Paramecium bursaria (Ciliophora, Oligohymenophorea).},
journal = {European journal of protistology},
volume = {66},
number = {},
pages = {149-155},
doi = {10.1016/j.ejop.2018.09.003},
pmid = {30286318},
issn = {1618-0429},
abstract = {Chlorella variabilis, a symbiotic alga, is usually present in the cytoplasm of Paramecium bursaria, although it can be cultured in host-free conditions. Morphological and chemical properties of its cell wall were compared between its free-living and symbiotic states. Transmission electron microscopy (quick-freezing and freeze-substitution methods) revealed that the cell wall thickness of symbiotic C. variabilis was reduced to about half that of the free-living one. Chemical properties of the cell wall were examined by treatment with three fluorescent reagents (calcofluor white M2R, FITC-WGA, and FITC-LFA) having specific binding affinities to different polysaccharides. When the algae were re-introduced into Paramecium host cells, calcofluor fluorescence intensity reduced by about 50%. Calcofluor stains β-d-glucopyranose polysaccharides such as cellulose, N-acetylglucosamine, sialic acid, and glycosaminoglycans. Because treatment with cellulase showed no effect on calcofluor fluorescence intensity, we consider that cellulose is not majorly responsible for the stainability of calcofluor. Staining intensities of FITC-WGA and FITC-LFA were similar in the free-living and symbiotic conditions, suggesting that N-acetylglucosamine and sialic acid are also not responsible for the reduction in the stainability of calcofluor associated with intracellular symbiosis. The amount of glycosaminoglycans on the cell wall may decrease in C. variabilis present in the cytoplasm of P. bursaria.},
}
@article {pmid30285618,
year = {2018},
author = {Tsikou, D and Ramirez, EE and Psarrakou, IS and Wong, JE and Jensen, DB and Isono, E and Radutoiu, S and Papadopoulou, KK},
title = {A Lotus japonicus E3 ligase interacts with the Nod Factor Receptor 5 and positively regulates nodulation.},
journal = {BMC plant biology},
volume = {18},
number = {1},
pages = {217},
doi = {10.1186/s12870-018-1425-z},
pmid = {30285618},
issn = {1471-2229},
support = {3817//Department of Biochemistry and Biotechnology/ ; 290713-031130//European Cooperation in Science and Technology/ ; DNRF79//Danmarks Grundforskningsfond/ ; },
mesh = {Gene Expression Regulation, Plant ; Loteae/*physiology ; Mesorhizobium/physiology ; Mutation ; Plant Proteins/genetics/*metabolism ; Plant Root Nodulation/*physiology ; Plants, Genetically Modified ; Protein-Serine-Threonine Kinases/metabolism ; Root Nodules, Plant/genetics/microbiology ; Symbiosis ; Ubiquitin-Protein Ligases/genetics/metabolism ; Ubiquitination ; },
abstract = {BACKGROUND: Post-translational modification of receptor proteins is involved in activation and de-activation of signalling systems in plants. Both ubiquitination and deubiquitination have been implicated in plant interactions with pathogens and symbionts.<br><br>RESULTS: Here we present LjPUB13, a PUB-ARMADILLO repeat E3 ligase that specifically ubiquitinates the kinase domain of the Nod Factor receptor NFR5 and has a direct role in nodule organogenesis events in Lotus japonicus. Phenotypic analyses of three LORE1 retroelement insertion plant lines revealed that pub13 plants display delayed and reduced nodulation capacity and retarded growth. LjPUB13 expression is spatially regulated during symbiosis with Mesorhizobium loti, with increased levels in young developing nodules.<br><br>CONCLUSION: LjPUB13 is an E3 ligase with a positive regulatory role during the initial stages of nodulation in L. japonicus.},
}
@article {pmid30284535,
year = {2018},
author = {Malolepszy, A and Kelly, S and Sørensen, KK and James, EK and Kalisch, C and Bozsoki, Z and Panting, M and Andersen, SU and Sato, S and Tao, K and Jensen, DB and Vinther, M and Jong, N and Madsen, LH and Umehara, Y and Gysel, K and Berentsen, MU and Blaise, M and Jensen, KJ and Thygesen, MB and Sandal, N and Andersen, KR and Radutoiu, S},
title = {A plant chitinase controls cortical infection thread progression and nitrogen-fixing symbiosis.},
journal = {eLife},
volume = {7},
number = {},
pages = {},
doi = {10.7554/eLife.38874},
pmid = {30284535},
issn = {2050-084X},
support = {DNRF79//Danish National Research Foundation/International ; 201604910506//China Scholarship Council/International ; DNRF79//Danish Reasearch Foundation/International ; },
abstract = {Morphogens provide positional information and their concentration is key to the organized development of multicellular organisms. Nitrogen-fixing root nodules are unique organs induced by Nod factor-producing bacteria. Localized production of Nod factors establishes a developmental field within the root where plant cells are reprogrammed to form infection threads and primordia. We found that regulation of Nod factor levels by Lotus japonicus is required for the formation of nitrogen-fixing organs, determining the fate of this induced developmental program. Our analysis of plant and bacterial mutants shows that a host chitinase modulates Nod factor levels possibly in a structure-dependent manner. In Lotus, this is required for maintaining Nod factor signalling in parallel with the elongation of infection threads within the nodule cortex, while root hair infection and primordia formation are not influenced. Our study shows that infected nodules require balanced levels of Nod factors for completing their transition to functional, nitrogen-fixing organs.},
}
@article {pmid30283478,
year = {2018},
author = {Zhu, X and Cao, Q and Sun, L and Yang, X and Yang, W and Zhang, H},
title = {Stomatal Conductance and Morphology of Arbuscular Mycorrhizal Wheat Plants Response to Elevated CO2 and NaCl Stress.},
journal = {Frontiers in plant science},
volume = {9},
number = {},
pages = {1363},
doi = {10.3389/fpls.2018.01363},
pmid = {30283478},
issn = {1664-462X},
abstract = {Stomata play a critical role in the regulation of gas exchange between the interior of the leaf and the exterior environment and are affected by environmental and endogenous stimuli. This study aimed to evaluate the effect of the arbuscular mycorrhizal (AM) fungus, Rhizophagus irregularis, on the stomatal behavior of wheat (Triticum aestivum L.) plants under combination with elevated CO2 and NaCl stress. Wheat seedlings were exposed to ambient (400 ppm) or elevated (700 ppm) CO2 concentrations and 0, 1, and 2 g kg-1 dry soil NaCl treatments for 10 weeks. AM symbiosis increased the leaf area and stomatal density (SD) of the abaxial surface. Stomatal size and the aperture of adaxial and abaxial leaf surfaces were higher in the AM than non-AM plants under elevated CO2 and salinity stress. AM plants showed higher stomatal conductance (gs) and maximum rate of gs to water vapor (gsmax) compared with non-AM plants. Moreover, leaf water potential (Ψ) was increased and carbon isotope discrimination (Δ13C) was decreased by AM colonization, and both were significantly associated with stomatal conductance. The results suggest that AM symbiosis alters stomatal morphology by changing SD and the size of the guard cells and stomatal pores, thereby improving the stomatal conductance and water relations of wheat leaves under combined elevated CO2 and salinity stress.},
}
@article {pmid30282739,
year = {2018},
author = {Li, H and Sosa-Calvo, J and Horn, HA and Pupo, MT and Clardy, J and Rabeling, C and Schultz, TR and Currie, CR},
title = {Convergent evolution of complex structures for ant-bacterial defensive symbiosis in fungus-farming ants.},
journal = {Proceedings of the National Academy of Sciences of the United States of America},
volume = {115},
number = {42},
pages = {10720-10725},
doi = {10.1073/pnas.1809332115},
pmid = {30282739},
issn = {1091-6490},
support = {U19 AI109673/AI/NIAID NIH HHS/United States ; U19 TW009872/TW/FIC NIH HHS/United States ; },
abstract = {Evolutionary adaptations for maintaining beneficial microbes are hallmarks of mutualistic evolution. Fungus-farming &quot;attine&quot; ant species have complex cuticular modifications and specialized glands that house and nourish antibiotic-producing Actinobacteria symbionts, which in turn protect their hosts' fungus gardens from pathogens. Here we reconstruct ant-Actinobacteria evolutionary history across the full range of variation within subtribe Attina by combining dated phylogenomic and ultramorphological analyses. Ancestral-state analyses indicate the ant-Actinobacteria symbiosis arose early in attine-ant evolution, a conclusion consistent with direct observations of Actinobacteria on fossil ants in Oligo-Miocene amber. qPCR indicates that the dominant ant-associated Actinobacteria belong to the genus Pseudonocardia Tracing the evolutionary trajectories of Pseudonocardia-maintaining mechanisms across attine ants reveals a continuum of adaptations. In Myrmicocrypta species, which retain many ancestral morphological and behavioral traits, Pseudonocardia occur in specific locations on the legs and antennae, unassociated with any specialized structures. In contrast, specialized cuticular structures, including crypts and tubercles, evolved at least three times in derived attine-ant lineages. Conspicuous caste differences in Pseudonocardia-maintaining structures, in which specialized structures are present in worker ants and queens but reduced or lost in males, are consistent with vertical Pseudonocardia transmission. Although the majority of attine ants are associated with Pseudonocardia, there have been multiple losses of bacterial symbionts and bacteria-maintaining structures in different lineages over evolutionary time. The early origin of ant-Pseudonocardia mutualism and the multiple evolutionary convergences on strikingly similar anatomical adaptations for maintaining bacterial symbionts indicate that Pseudonocardia have played a critical role in the evolution of ant fungiculture.},
}
@article {pmid30282650,
year = {2018},
author = {Hecht, LBB and Thompson, PC and Rosenthal, BM},
title = {Comparative demography elucidates the longevity of parasitic and symbiotic relationships.},
journal = {Proceedings. Biological sciences},
volume = {285},
number = {1888},
pages = {},
doi = {10.1098/rspb.2018.1032},
pmid = {30282650},
issn = {1471-2954},
abstract = {Parasitic and symbiotic relationships govern vast nutrient and energy flows, yet controversy surrounds their longevity. Enduring relationships may engender parallel phylogenies among hosts and parasites, but so may ephemeral relationships when parasites colonize related hosts. An understanding of whether symbiont and host populations have grown and contracted in concert would be useful when considering the temporal durability of these relationships. Here, we devised methods to compare demographic histories derived from genomic data. We compared the historical growth of the agent of severe human malaria, Plasmodium falciparum, and its mosquito vector, Anopheles gambiae, to human and primate histories, thereby discerning long-term parallels and anthropogenic population explosions. The growth history of Trichinella spiralis, a zoonotic parasite disseminated by swine, proved regionally specific, paralleling distinctive growth histories for wild boar in Asia and Europe. Parallel histories were inferred for an anemone and its algal symbiont (Exaiptasia pallida and Symbiodinium minutum). Concerted growth in potatoes and the agent of potato blight (Solanum tuberosum and Phytophthora infestans) did not commence until the age of potato domestication. Through these examples, we illustrate the utility of comparative historical demography as a new exploratory tool by which to interrogate the origins and durability of myriad ecological relationships. To facilitate future use of this approach, we introduce a tool called C-PSMC to align and evaluate the similarity of demographic history curves.},
}
@article {pmid30276818,
year = {2018},
author = {Giauque, H and Connor, EW and Hawkes, CV},
title = {Endophyte traits relevant to stress tolerance, resource use and habitat of origin predict effects on host plants.},
journal = {The New phytologist},
volume = {},
number = {},
pages = {},
doi = {10.1111/nph.15504},
pmid = {30276818},
issn = {1469-8137},
support = {//University of Texas Green Fee/ ; //Texas Ecolab/ ; //University of Texas Plant Biology Graduate Program/ ; },
abstract = {All terrestrial plants are colonized by foliar endophytic fungi that can affect plant growth and physiology, but the prediction of these effects on the plant host remains a challenge. Here, we examined three paradigms that potentially control how endophytes affect plant hosts: habitat adaptation, evolutionary history and functional traits. We screened 35 plant-endophyte pairings in a microcosm experiment under well-watered and drought conditions with Panicum virgatum as the host. We related the measured plant responses to fungal phylogenetic relatedness, characteristics of fungal habitats across a rainfall gradient and functional traits of the fungi related to stress tolerance and resource use. The functional traits and habitat characteristics of the fungi predicted 26-53% of endophyte-mediated effects on measures of plant growth, physiology and survival. Overall, survival was higher for plants grown with more stress-tolerant fungi, and aboveground biomass was enhanced by fungi from warmer and drier habitats. Plant growth and physiology were also dependent on fungal resource use indicators; however, specific predictors were dependent on water availability. Simple ecological traits of foliar endophytic fungi observed in culture can translate to symbiotic lifestyles. These findings offer new insights and key testable predictions for likely pathways by which endophytes benefit the plant host.},
}
@article {pmid30275294,
year = {2018},
author = {Ledón-Rettig, CC and Moczek, AP and Ragsdale, EJ},
title = {Diplogastrellus nematodes are sexually transmitted mutualists that alter the bacterial and fungal communities of their beetle host.},
journal = {Proceedings of the National Academy of Sciences of the United States of America},
volume = {115},
number = {42},
pages = {10696-10701},
doi = {10.1073/pnas.1809606115},
pmid = {30275294},
issn = {1091-6490},
abstract = {A recent accumulation of studies has demonstrated that nongenetic, maternally transmitted factors are often critical to the health and development of offspring and can therefore play a role in ecological and evolutionary processes. In particular, microorganisms such as bacteria have been championed as heritable, symbiotic partners capable of conferring fitness benefits to their hosts. At the same time, parents may also pass various nonmicrobial organisms to their offspring, yet the roles of such organisms in shaping the developmental environment of their hosts remain largely unexplored. Here, we show that the nematode Diplogastrellus monhysteroides is transgenerationally inherited and sexually transmitted by the dung beetle Onthophagus taurus By manipulating artificial chambers in which beetle offspring develop, we demonstrate that the presence of D. monhysteroides nematodes enhances the growth of beetle offspring, empirically challenging the paradigm that nematodes are merely commensal or even detrimental to their insect hosts. Finally, our research presents a compelling mechanism whereby the nematodes influence the health of beetle larvae: D. monhysteroides nematodes engineer the bacterial and fungal communities that also inhabit the beetle developmental chambers, including specific taxa known to be involved in biomass degradation, possibly allowing larval beetles better access to their otherwise recalcitrant, plant-based diet. Thus, our findings illustrate that nongenetic inheritance can include intermediately sized organisms that live and proliferate in close association with, and in certain cases enhance, the development of their hosts' offspring.},
}
@article {pmid30273416,
year = {2018},
author = {Liu, H and Stephens, TG and González-Pech, RA and Beltran, VH and Lapeyre, B and Bongaerts, P and Cooke, I and Aranda, M and Bourne, DG and Forêt, S and Miller, DJ and van Oppen, MJH and Voolstra, CR and Ragan, MA and Chan, CX},
title = {Erratum: Publisher Correction: Symbiodinium genomes reveal adaptive evolution of functions related to coral-dinoflagellate symbiosis.},
journal = {Communications biology},
volume = {1},
number = {},
pages = {126},
doi = {10.1038/s42003-018-0117-4},
pmid = {30273416},
issn = {2399-3642},
abstract = {[This corrects the article DOI: 10.1038/s42003-018-0098-3.].},
}
@article {pmid30271996,
year = {2018},
author = {Hoeksema, JD and Bever, JD and Chakraborty, S and Chaudhary, VB and Gardes, M and Gehring, CA and Hart, MM and Housworth, EA and Kaonongbua, W and Klironomos, JN and Lajeunesse, MJ and Meadow, J and Milligan, BG and Piculell, BJ and Pringle, A and Rúa, MA and Umbanhowar, J and Viechtbauer, W and Wang, YW and Wilson, GWT and Zee, PC},
title = {Evolutionary history of plant hosts and fungal symbionts predicts the strength of mycorrhizal mutualism.},
journal = {Communications biology},
volume = {1},
number = {},
pages = {116},
doi = {10.1038/s42003-018-0120-9},
pmid = {30271996},
issn = {2399-3642},
abstract = {Most plants engage in symbioses with mycorrhizal fungi in soils and net consequences for plants vary widely from mutualism to parasitism. However, we lack a synthetic understanding of the evolutionary and ecological forces driving such variation for this or any other nutritional symbiosis. We used meta-analysis across 646 combinations of plants and fungi to show that evolutionary history explains substantially more variation in plant responses to mycorrhizal fungi than the ecological factors included in this study, such as nutrient fertilization and additional microbes. Evolutionary history also has a different influence on outcomes of ectomycorrhizal versus arbuscular mycorrhizal symbioses; the former are best explained by the multiple evolutionary origins of ectomycorrhizal lifestyle in plants, while the latter are best explained by recent diversification in plants; both are also explained by evolution of specificity between plants and fungi. These results provide the foundation for a synthetic framework to predict the outcomes of nutritional mutualisms.},
}
@article {pmid30271976,
year = {2018},
author = {Liu, H and Stephens, TG and González-Pech, RA and Beltran, VH and Lapeyre, B and Bongaerts, P and Cooke, I and Aranda, M and Bourne, DG and Forêt, S and Miller, DJ and van Oppen, MJH and Voolstra, CR and Ragan, MA and Chan, CX},
title = {Symbiodinium genomes reveal adaptive evolution of functions related to coral-dinoflagellate symbiosis.},
journal = {Communications biology},
volume = {1},
number = {},
pages = {95},
doi = {10.1038/s42003-018-0098-3},
pmid = {30271976},
issn = {2399-3642},
abstract = {Symbiosis between dinoflagellates of the genus Symbiodinium and reef-building corals forms the trophic foundation of the world's coral reef ecosystems. Here we present the first draft genome of Symbiodinium goreaui (Clade C, type C1: 1.03 Gbp), one of the most ubiquitous endosymbionts associated with corals, and an improved draft genome of Symbiodinium kawagutii (Clade F, strain CS-156: 1.05 Gbp) to further elucidate genomic signatures of this symbiosis. Comparative analysis of four available Symbiodinium genomes against other dinoflagellate genomes led to the identification of 2460 nuclear gene families (containing 5% of Symbiodinium genes) that show evidence of positive selection, including genes involved in photosynthesis, transmembrane ion transport, synthesis and modification of amino acids and glycoproteins, and stress response. Further, we identify extensive sets of genes for meiosis and response to light stress. These draft genomes provide a foundational resource for advancing our understanding of Symbiodinium biology and the coral-algal symbiosis.},
}
@article {pmid30271534,
year = {2018},
author = {Birnbaum, C and Morald, TK and Tibbett, M and Bennett, RG and Standish, RJ},
title = {Effect of plant root symbionts on performance of native woody species in competition with an invasive grass in multispecies microcosms.},
journal = {Ecology and evolution},
volume = {8},
number = {17},
pages = {8652-8664},
doi = {10.1002/ece3.4397},
pmid = {30271534},
issn = {2045-7758},
abstract = {The majority of terrestrial plants form mutualistic associations with arbuscular mycorrhizal fungi (AMF) and rhizobia (i.e., nitrogen-fixing bacteria). Understanding these associations has important implications for ecological theory and for restoration practice. Here, we tested whether the presence of AMF and rhizobia influences the performance of native woody plants invaded by a non-native grass in experimental microcosms. We planted eight plant species (i.e., Acacia acuminata, A. microbotrya, Eucalyptus loxophleba subsp. loxophleba, E. astringens, Calothamnus quadrifidus, Callistemon phoeniceus, Hakea lissocarpha and H. prostrata) in microcosms of field-conditioned soil with and without addition of AMF and rhizobia in a fully factorial experimental design. After seedling establishment, we seeded half the microcosms with an invasive grass Bromus diandrus. We measured shoot and root biomass of native plants and Bromus, and on roots, the percentage colonization by AMF, number of rhizobia-forming nodules and number of proteaceous root clusters. We found no effect of plant root symbionts or Bromus addition on performance of myrtaceous, and as predicted, proteaceous species as they rely little or not at all on AMF and rhizobia. Soil treatments with AMF and rhizobia had a strong positive effect (i.e., larger biomass) on native legumes (A. microbotrya and A. acuminata). However, the beneficial effect of root symbionts on legumes became negative (i.e., lower biomass and less nodules) if Bromus was present, especially for one legume, i.e., A. acuminata, suggesting a disruptive effect of the invader on the mutualism. We also found a stimulating effect of Bromus on root nodule production in A. microbotrya and AMF colonization in A. acuminata which could be indicative of legumes' increased resource acquisition requirement, i.e., for nitrogen and phosphorus, respectively, in response to the Bromus addition. We have demonstrated the importance of measuring belowground effects because the aboveground effects gave limited indication of the effects occurring belowground.},
}
@article {pmid30271387,
year = {2018},
author = {Mohammed, M and Jaiswal, SK and Sowley, ENK and Ahiabor, BDK and Dakora, FD},
title = {Symbiotic N2 Fixation and Grain Yield of Endangered Kersting's Groundnut Landraces in Response to Soil and Plant Associated Bradyrhizobium Inoculation to Promote Ecological Resource-Use Efficiency.},
journal = {Frontiers in microbiology},
volume = {9},
number = {},
pages = {2105},
doi = {10.3389/fmicb.2018.02105},
pmid = {30271387},
issn = {1664-302X},
abstract = {Kersting's groundnut (Macrotyloma geocarpum Harms) is a neglected, endangered food and medicinal legume in Africa. Efforts to harness the benefits of the legume-rhizobia symbiosis have focused on few major legumes to the neglect of underutilized ones such as Kersting's groundnut. This study assessed plant growth, N-fixed and grain yield of five Kersting's groundnut landraces in response to inoculation with Bradyrhizobium strain CB756 at two locations in the Northern Region of Ghana. The transferability of cowpea-derived Simple Sequence Repeat (SSR) markers to Kersting's groundnut was also assessed. The symbiotic results revealed significant variation in nodulation, shoot biomass, δ15N, percent N derived from fixation, amount of N-fixed and soil N uptake. The cross-taxa SSR primers revealed monomorphic bands with sizes within the expected range in all the Kersting's groundnut landraces. The results of the aligned nucleotide sequences revealed marked genetic variability among the landraces. Kersting's groundnut was found to be a low N2-fixer, with 28-45% of its N derived from fixation at Nyankpala and 15-29% at Savelugu. Nitrogen contribution was 28-50 kg N-fixed·ha-1 at Nyankpala, and 12-32 kg N-fixed·ha-1 at Savelugu. Uninoculated plants of the Kersting's groundnut landraces Puffeun, Dowie, Sigiri and Boli, respectively, contributed 22, 16, 13, and 15 kg N-fixed·ha-1 from symbiosis at Savelugu as opposed to 89, 82, 69, and 89 kg N·ha-1 from soil. Landrace Puffeun was highly compatible with the introduced strain CB756 if based on δ15N and %Ndfa values, while Dowie, Funsi and Boli showed greater compatibility with native rhizobia in Ghanaian soils. The unimproved Kersting's groundnut in association with soil microsymbionts could produce grain yield of 1,137-1,556 kg ha-1 at Nyankpala, and 921-1,192 kg ha-1 at Savelugu. These findings suggest the need for further work to improve the efficiency of the Kersting's groundnut-rhizobia symbiosis for increased grain yield and resource-use efficiency in cropping systems.},
}
@article {pmid30268783,
year = {2019},
author = {Mansfield, KM and Gilmore, TD},
title = {Innate immunity and cnidarian-Symbiodiniaceae mutualism.},
journal = {Developmental and comparative immunology},
volume = {90},
number = {},
pages = {199-209},
doi = {10.1016/j.dci.2018.09.020},
pmid = {30268783},
issn = {1879-0089},
abstract = {The phylum Cnidaria (sea anemones, corals, hydra, jellyfish) is one the most distantly related animal phyla to humans, and yet cnidarians harbor many of the same cellular pathways involved in innate immunity in mammals. In addition to its role in pathogen recognition, the innate immune system has a role in managing beneficial microbes and supporting mutualistic microbial symbioses. Some corals and sea anemones undergo mutualistic symbioses with photosynthetic algae in the family Symbiodiniaceae. These symbioses can be disrupted by anthropogenic disturbances of ocean environments, which can have devastating consequences for the health of coral reef ecosystems. Several studies of cnidarian-Symbiodiniaceae symbiosis have implicated proteins in the host immune system as playing a role in both symbiont tolerance and loss of symbiosis (i.e., bleaching). In this review, we critically evaluate current knowledge about the role of host immunity in the regulation of symbiosis in cnidarians.},
}
@article {pmid30267435,
year = {2018},
author = {Prasad, S and Rastogi, B and Shah, A and Bhalsing, KS and Ingalhalikar, M and Saini, J and Yadav, R and Pal, PK},
title = {DTI in essential tremor with and without rest tremor: Two sides of the same coin?.},
journal = {Movement disorders : official journal of the Movement Disorder Society},
volume = {33},
number = {11},
pages = {1820-1821},
doi = {10.1002/mds.27459},
pmid = {30267435},
issn = {1531-8257},
support = {ECR/2016/000808//Symbiosis International University/ ; //DST SERB, India/ ; },
}
@article {pmid30266750,
year = {2018},
author = {Li, X and Zheng, J and Yang, Y and Liao, H},
title = {INCREASING NODULE SIZE1 Expression Is Required for Normal Rhizobial Symbiosis and Nodule Development.},
journal = {Plant physiology},
volume = {178},
number = {3},
pages = {1233-1248},
doi = {10.1104/pp.18.01018},
pmid = {30266750},
issn = {1532-2548},
abstract = {Nodulation is crucial for biological nitrogen fixation (BNF) in legumes, but the molecular mechanisms underlying BNF have remained elusive. Here, we cloned a candidate gene underlying a major nodulation quantitative trait locus in soybean (Glycine max), INCREASING NODULE SIZE1 (GmINS1). GmINS1 encodes a cell wall β-expansin and is expressed primarily in vascular bundles, along with cortical and parenchyma cells of nodules. Four single-nucleotide polymorphisms distinguishing the two parents were found in the GmINS1 promoter region. Among them, single-nucleotide polymorphism A/C has a significant effect on GmINS1 expression in the parental genotype P2, based on β-glucuronidase activity and promoter deletion analysis. The expression of GmINS1 and the P2 genotype promoter was strongly associated with nodule development, not only in the parents but also in 40 progeny lines and 40 genotypes selected from a soybean core collection. Overexpression of GmINS1 resulted in increases in the number, biomass, infection cell abundance, and nitrogenase activity of large nodules and subsequently changed the nitrogen content and biomass of soybean plants. GmINS1 suppression via RNA interference had the opposite effect. Double suppression of GmEXPB2 and GmINS1 dramatically inhibited soybean nodulation. Our results reveal that GmINS1 is a critical gene in nodule development and that GmEXPB2 and GmINS1 synergistically control nodulation in soybean. Our findings shed light on the genetic basis of soybean nodulation and provide a candidate gene for optimizing BNF capacity through molecular breeding in soybean.},
}
@article {pmid30263059,
year = {2018},
author = {Pouncey, AL and Scott, AJ and Alexander, JL and Marchesi, J and Kinross, J},
title = {Gut microbiota, chemotherapy and the host: the influence of the gut microbiota on cancer treatment.},
journal = {Ecancermedicalscience},
volume = {12},
number = {},
pages = {868},
doi = {10.3332/ecancer.2018.868},
pmid = {30263059},
issn = {1754-6605},
abstract = {The gut microbiota exists in a dynamic balance between symbiosis and pathogenesis and can influence almost any aspect of host physiology. Growing evidence suggests that the gut microbiota not only plays a key role in carcinogenesis but also influences the efficacy and toxicity of anticancer therapy. The microbiota modulates the host response to chemotherapy via numerous mechanisms, including immunomodulation, xenometabolism and alteration of community structure. Furthermore, exploitation of the microbiota offers opportunities for the personalisation of chemotherapeutic regimens and the development of novel therapies. In this article, we explore the host-chemotherapeutic microbiota axis, from basic science to clinical research, and describe how it may change the face of cancer treatment.},
}
@article {pmid30259496,
year = {2018},
author = {Hinzke, T and Kleiner, M and Markert, S},
title = {Centrifugation-Based Enrichment of Bacterial Cell Populations for Metaproteomic Studies on Bacteria-Invertebrate Symbioses.},
journal = {Methods in molecular biology (Clifton, N.J.)},
volume = {1841},
number = {},
pages = {319-334},
doi = {10.1007/978-1-4939-8695-8_22},
pmid = {30259496},
issn = {1940-6029},
abstract = {Owing to high sample complexity, metaproteomic investigations on bacteria-animal symbioses with two or more uncultured partners can be challenging. A selective isolation or enrichment of distinct (sub-)populations within those consortia can solve this problem. Subsequent discrete proteomic analyses benefit from increased sample purity and higher proteome coverage for each of the individual organisms. Here, we describe centrifugation-based methods that allow for a separation of the host and its bacterial symbiont population(s), or even for an enrichment of distinct symbiotic cell cycle stages in the deep-sea mussels Bathymodiolus azoricus and B. thermophilus, the gutless oligochaete Olavius algarvensis and the deep-sea tube worm Riftia pachyptila, respectively.},
}
@article {pmid30258414,
year = {2018},
author = {Lorite, MJ and Estrella, MJ and Escaray, FJ and Sannazzaro, A and Videira E Castro, IM and Monza, J and Sanjuán, J and León-Barrios, M},
title = {The Rhizobia-Lotus Symbioses: Deeply Specific and Widely Diverse.},
journal = {Frontiers in microbiology},
volume = {9},
number = {},
pages = {2055},
doi = {10.3389/fmicb.2018.02055},
pmid = {30258414},
issn = {1664-302X},
abstract = {The symbiosis between Lotus and rhizobia has been long considered very specific and only two bacterial species were recognized as the microsymbionts of Lotus: Mesorhizobium loti was considered the typical rhizobia for the L. corniculatus complex, whereas Bradyrhizobium sp. (Lotus) was the symbiont for L. uliginosus and related species. As discussed in this review, this situation has dramatically changed during the last 15 years, with the characterization of nodule bacteria from worldwide geographical locations and from previously unexplored Lotus spp. Current data support that the Lotus rhizobia are dispersed amongst nearly 20 species in five genera (Mesorhizobium, Bradyrhizobium, Rhizobium, Ensifer, and Aminobacter). As a consequence, M. loti could be regarded an infrequent symbiont of Lotus, and several plant-bacteria compatibility groups can be envisaged. Despite the great progress achieved with the model L. japonicus in understanding the establishment and functionality of the symbiosis, the genetic and biochemical bases governing the stringent host-bacteria compatibility pairships within the genus Lotus await to be uncovered. Several Lotus spp. are grown for forage, and inoculation with rhizobia is a common practice in various countries. However, the great diversity of the Lotus rhizobia is likely squandered, as only few bacterial strains are used as inoculants for Lotus pastures in very different geographical locations, with a great variety of edaphic and climatic conditions. The agroecological potential of the genus Lotus can not be fully harnessed without acknowledging the great diversity of rhizobia-Lotus interactions, along with a better understanding of the specific plant and bacterial requirements for optimal symbiotic nitrogen fixation under increasingly constrained environmental conditions.},
}
@article {pmid30257087,
year = {2018},
author = {Meng, F and Seredych, M and Chen, C and Gura, V and Mikhalovsky, S and Sandeman, S and Ingavle, G and Ozulumba, T and Miao, L and Anasori, B and Gogotsi, Y},
title = {MXene Sorbents for Removal of Urea from Dialysate: A Step toward the Wearable Artificial Kidney.},
journal = {ACS nano},
volume = {12},
number = {10},
pages = {10518-10528},
doi = {10.1021/acsnano.8b06494},
pmid = {30257087},
issn = {1936-086X},
abstract = {The wearable artificial kidney can deliver continuous ambulatory dialysis for more than 3 million patients with end-stage renal disease. However, the efficient removal of urea is a key challenge in miniaturizing the device and making it light and small enough for practical use. Here, we show that two-dimensional titanium carbide (MXene) with the composition of Ti3C2T x, where T x represents surface termination groups such as -OH, -O-, and -F, can adsorb urea, reaching 99% removal efficiency from aqueous solution and 94% from dialysate at the initial urea concentration of 30 mg/dL, with the maximum urea adsorption capacity of 10.4 mg/g at room temperature. When tested at 37 °C, we achieved a 2-fold increase in urea removal efficiency from dialysate, with the maximum urea adsorption capacity of 21.7 mg/g. Ti3C2T x showed good hemocompatibility; it did not induce cell apoptosis or reduce the metabolizing cell fraction, indicating no impact on cell viability at concentrations of up to 200 μg/mL. The biocompatibility of Ti3C2T x and its selectivity for urea adsorption from dialysate open a new opportunity in designing a miniaturized dialysate regeneration system for a wearable artificial kidney.},
}
@article {pmid30255557,
year = {2018},
author = {Hage-Ahmed, K and Rosner, K and Steinkellner, S},
title = {Arbuscular mycorrhizal fungi and their response to pesticides.},
journal = {Pest management science},
volume = {},
number = {},
pages = {},
doi = {10.1002/ps.5220},
pmid = {30255557},
issn = {1526-4998},
abstract = {Arbuscular mycorrhizal fungi (AMF) form symbioses with the majority of plant species and can provide multiple benefits to the host plant. In agro-ecosystems, the abundance and community structure of AMF are affected by agricultural management practices. This review describes and discusses current knowledge on the effects of inorganic and organic chemical pesticides on AMF in the conflicting area between agricultural use and environmental concerns. Variable effects have been reported following chemical pesticide use, ranging from neutral to positive and negative. Moreover, a species-specific reaction has been documented. The reported effects of pesticides on arbuscular mycorrhizal symbiosis are very diverse, and even when the same substance is investigated, the results are often contradictory. These effects depend on many parameters, such as the active substance, the mode of action, the mode of application and the dosage. In the field, determinants such as the physico-chemical behavior of the active substances, the soil type and other soil microorganisms contribute to the fate of pesticides and thus the amount of active substances to which AMF are exposed. This review highlights that the fate of AMF following pesticide use needs to be addressed in a broader agro-ecosystem context. © 2018 The Authors. Pest Management Science published by John Wiley &amp; Sons Ltd on behalf of Society of Chemical Industry.},
}
@article {pmid30255541,
year = {2018},
author = {Cornejo-Castillo, FM and Muñoz-Marín, MDC and Turk-Kubo, KA and Royo-Llonch, M and Farnelid, H and Acinas, SG and Zehr, JP},
title = {UCYN-A3, a newly characterized open ocean sublineage of the symbiotic N2 -fixing cyanobacterium Candidatus Atelocyanobacterium thalassa.},
journal = {Environmental microbiology},
volume = {},
number = {},
pages = {},
doi = {10.1111/1462-2920.14429},
pmid = {30255541},
issn = {1462-2920},
support = {//Biosensomics to SGA (Convocatoria 2015 de ayudas Fundación BBVA a investigadores y creadores culturales)/ ; FPI (BES-2014-068285)//Consejo Superior de Investigaciones Científicas/ ; 493.01//Gordon and Betty Moore Foundation/ ; //Marie Curie International Outgoing Fellowship/ ; 329108//Simons Collaboration on Ocean Processes and Ecology (SCOPE)/ ; 545171//Simons Foundation/ ; //Spanish Ministry of Economy, Industry and Competitiveness/ ; VR 637-2013-7502//Svenska Forskningsrådet Formas/ ; },
abstract = {The symbiotic unicellular cyanobacterium Candidatus Atelocyanobacterium thalassa (UCYN-A) is one of the most abundant and widespread nitrogen (N2)-fixing cyanobacteria in the ocean. Although it remains uncultivated, multiple sublineages have been detected based on partial nitrogenase (nifH) gene sequences, including the four most commonly detected sublineages UCYN-A1, UCYN-A2, UCYN-A3 and UCYN-A4. However, very little is known about UCYN-A3 beyond the nifH sequences from nifH gene diversity surveys. In this study, single cell sorting, DNA sequencing, qPCR and CARD-FISH assays revealed discrepancies involving the identification of sublineages, which led to new information on the diversity of the UCYN-A symbiosis. 16S rRNA and nifH gene sequencing on single sorted cells allowed us to identify the 16S rRNA gene of the uncharacterized UCYN-A3 sublineage. We designed new CARD-FISH probes that allowed us to distinguish and observe UCYN-A2 in a coastal location (SIO Pier; San Diego) and UCYN-A3 in an open ocean location (Station ALOHA; Hawaii). Moreover, we reconstructed about 13% of the UCYN-A3 genome from Tara Oceans metagenomic data. Finally, our findings unveil the UCYN-A3 symbiosis in open ocean waters suggesting that the different UCYN-A sublineages are distributed along different size fractions of the plankton defined by the cell-size ranges of their prymnesiophyte hosts.},
}
@article {pmid30254121,
year = {2018},
author = {Ankrah, NYD and Chouaia, B and Douglas, AE},
title = {The Cost of Metabolic Interactions in Symbioses between Insects and Bacteria with Reduced Genomes.},
journal = {mBio},
volume = {9},
number = {5},
pages = {},
doi = {10.1128/mBio.01433-18},
pmid = {30254121},
issn = {2150-7511},
abstract = {Various intracellular bacterial symbionts that provide their host with essential nutrients have much-reduced genomes, attributed largely to genomic decay and relaxed selection. To obtain quantitative estimates of the metabolic function of these bacteria, we reconstructed genome- and transcriptome-informed metabolic models of three xylem-feeding insects that bear two bacterial symbionts with complementary metabolic functions: a primary symbiont, Sulcia, that has codiversified with the insects, and a coprimary symbiont of distinct taxonomic origin and with different degrees of genome reduction in each insect species (Hodgkinia in a cicada, Baumannia in a sharpshooter, and Sodalis in a spittlebug). Our simulations reveal extensive bidirectional flux of multiple metabolites between each symbiont and the host, but near-complete metabolic segregation (i.e., near absence of metabolic cross-feeding) between the two symbionts, a likely mode of host control over symbiont metabolism. Genome reduction of the symbionts is associated with an increased number of host metabolic inputs to the symbiont and also reduced metabolic cost to the host. In particular, Sulcia and Hodgkinia with genomes of ≤0.3 Mb are calculated to recycle ∼30 to 80% of host-derived nitrogen to essential amino acids returned to the host, while Baumannia and Sodalis with genomes of ≥0.6 Mb recycle 10 to 15% of host nitrogen. We hypothesize that genome reduction of symbionts may be driven by selection for increased host control and reduced host costs, as well as by the stochastic process of genomic decay and relaxed selection.IMPORTANCE Current understanding of many animal-microbial symbioses involving unculturable bacterial symbionts with much-reduced genomes derives almost entirely from nonquantitative inferences from genome data. To overcome this limitation, we reconstructed multipartner metabolic models that quantify both the metabolic fluxes within and between three xylem-feeding insects and their bacterial symbionts. This revealed near-complete metabolic segregation between cooccurring bacterial symbionts, despite extensive metabolite exchange between each symbiont and the host, suggestive of strict host controls over the metabolism of its symbionts. We extended the model analysis to investigate metabolic costs. The positive relationship between symbiont genome size and the metabolic cost incurred by the host points to fitness benefits to the host of bearing symbionts with small genomes. The multicompartment metabolic models developed here can be applied to other symbioses that are not readily tractable to experimental approaches.},
}
@article {pmid30253017,
year = {2018},
author = {Varga, S and Soulsbury, CD},
title = {Arbuscular mycorrhizal fungi change host plant DNA methylation systemically.},
journal = {Plant biology (Stuttgart, Germany)},
volume = {},
number = {},
pages = {},
doi = {10.1111/plb.12917},
pmid = {30253017},
issn = {1438-8677},
support = {//Pump Priming Scheme of the School of Life Sciences, University of Lincoln/ ; 660104//Marie Curie Fellowship/ ; },
abstract = {DNA methylation is an important epigenetic mechanism regulating gene expression in plants. DNA methylation has been shown to vary among species and also among plant tissues. However, no study has evaluated whether arbuscular mycorrhizal (AM) fungi affect DNA methylation levels in a tissue-specific manner. We investigated whether symbiosis with AM fungi affects DNA methylation in the host, focusing on different plant tissues (roots versus leaves) and across time. We carried out a 6-month pot experiment using Geranium robertianum in symbiosis with the AM fungus Funneliformis mosseae. Our results show that the pattern of total DNA methylation differed between leaves and roots and was related to when plants were harvested, confirming that DNA methylation is a process that occurs dynamically throughout an organism's lifetime. More importantly, the presence of AM fungus in roots of our experimental plants had a positive effect on total DNA methylation in both tissues. This study shows that colonisation by AM fungi can affect DNA methylation levels in their hosts and that plant DNA methylation varies in an age- and tissue-specific manner.},
}
@article {pmid30252618,
year = {2018},
author = {Berrabah, F and Ratet, P and Gourion, B},
title = {Legume Nodules: Massive Infection in the Absence of Defense Induction.},
journal = {Molecular plant-microbe interactions : MPMI},
volume = {},
number = {},
pages = {MPMI07180205FI},
doi = {10.1094/MPMI-07-18-0205-FI},
pmid = {30252618},
issn = {0894-0282},
abstract = {Plants of the legume family host massive intracellular bacterial populations in the tissues of specialized organs, the nodules. In these organs, the bacteria, named rhizobia, can fix atmospheric nitrogen and transfer it to the plant. This special metabolic skill provides to the legumes an advantage when they grow on nitrogen-scarce substrates. While packed with rhizobia, the nodule cells remain alive, metabolically active, and do not develop defense reactions. Here, we review our knowledge on the control of plant immunity during the rhizobia-legume symbiosis. We present the results of an evolutionary process that selected both divergence of microbial-associated molecular motifs and active suppressors of immunity on the rhizobial side and, on the legume side, active mechanisms that contribute to suppression of immunity.},
}
@article {pmid30251133,
year = {2018},
author = {Li, M and Wang, R and Tian, H and Gao, Y},
title = {Transcriptome responses in wheat roots to colonization by the arbuscular mycorrhizal fungus Rhizophagus irregularis.},
journal = {Mycorrhiza},
volume = {28},
number = {8},
pages = {747-759},
doi = {10.1007/s00572-018-0868-2},
pmid = {30251133},
issn = {1432-1890},
abstract = {The influence of arbuscular mycorrhizal (AM) colonization on the expression of genes in the roots of wheat (Triticum aestivum L.) at the transcriptome level is largely unknown. A pot experiment was established to study the responses of the transcriptome profile in the roots of wheat to colonization by the AM fungus Rhizophagus irregularis using high through-put sequencing methods. The results indicated that the expression of 11,746 genes was regulated by AM colonization, and 64.7% of them were up-regulated genes. 1106 genes were only expressed in roots colonized by AM fungi, and 108 genes were only expressed in non-mycorrhizal roots. The differentially expressed genes (DEGs) were primarily distributed on the 2B, 3B, 2A, 2D, and 5B chromosomes of wheat. The DEGs (including both up- and down- regulated) mainly located on membranes, and functioned in nucleotide binding and transferase activity during cellular protein modification and biosynthetic processes. The data revealed that AM colonization up-regulated genes involved in the phenylpropanoid biosynthesis pathway and transcription factors which play vital roles in protecting plants from biotic or abiotic stresses. A number of key genes involved in molecular signal biosynthesis and recognition, epidermal cell colonization and arbuscule formation, carbon and nutrients exchange during AM symbiosis were found. All the ammonium transporter (AMT), iron-phytosiderophore transporter, boron, zinc, and magnesium transporter genes found in our study were up-regulated DEGs. One new AM-specific induced AMT and three new AM-specific induced nitrate transporter (NRT) genes were found in the roots of wheat colonized by AM fungi, even though a negative growth response of wheat to AM colonization occurred. The present study provided new information which is important for understanding the mechanisms behind the development and function of the symbiosis between wheat and AM fungi.},
}
@article {pmid30250917,
year = {2018},
author = {Linden, CV and Corbet, C},
title = {Killing two birds with one stone: Blocking the mitochondrial pyruvate carrier to inhibit lactate uptake by cancer cells and radiosensitize tumors.},
journal = {Molecular &amp; cellular oncology},
volume = {5},
number = {4},
pages = {e1465016},
doi = {10.1080/23723556.2018.1465016},
pmid = {30250917},
issn = {2372-3556},
abstract = {Lactate-based metabolic symbiosis between glycolytic and oxidative cancer cells is known to facilitate tumor growth. We have recently demonstrated that 7ACC2 blocks extracellular lactate uptake via the inhibition of mitochondrial pyruvate carrier. 7ACC2 also prevents compensatory glucose oxidation, induces tumor reoxygenation and potentiates radiotherapy, making it a promising anticancer drug.},
}
@article {pmid30250634,
year = {2018},
author = {Wang, X and Luo, Y and Liu, D and Wang, J and Wei, S and Zhao, L},
title = {Complete genome sequence of the Robinia pseudoacacia L. symbiont Mesorhizobium amorphae CCNWGS0123.},
journal = {Standards in genomic sciences},
volume = {13},
number = {},
pages = {18},
doi = {10.1186/s40793-018-0321-3},
pmid = {30250634},
issn = {1944-3277},
abstract = {Mesorhizobium amorphae CCNWGS0123 was isolated in 2006, from effective nodules of Robinia pseudoacacia L. grown in lead-zinc mine tailing site, in Gansu Province, China. M. amorphae CCNWGS0123 is an aerobic, Gram-negative, non-spore-forming rod strain. This paper characterized M. amorphae CCNWGS0123 and presents its complete genome sequence information and genome annotation. The 7,374,589 bp long genome which encodes 7136 protein-coding genes and 63 RNA coding genes, contains one chromosome and four plasmids. Moreover, a chromosome with no gaps was assembled.},
}
@article {pmid30245343,
year = {2018},
author = {Duc, NH and Csintalan, Z and Posta, K},
title = {Arbuscular mycorrhizal fungi mitigate negative effects of combined drought and heat stress on tomato plants.},
journal = {Plant physiology and biochemistry : PPB},
volume = {132},
number = {},
pages = {297-307},
doi = {10.1016/j.plaphy.2018.09.011},
pmid = {30245343},
issn = {1873-2690},
mesh = {Antioxidants/metabolism ; Biomass ; Biosynthetic Pathways/genetics ; Chlorophyll/metabolism ; *Droughts ; Fluorescence ; Genes, Plant ; Heat-Shock Response/*physiology ; Hydrogen Peroxide/metabolism ; Lipid Peroxidation ; Lycopersicon esculentum/genetics/*microbiology/*physiology ; Malondialdehyde/metabolism ; Mycorrhizae/*physiology ; Photosystem II Protein Complex/metabolism ; Plant Development ; Plant Leaves/enzymology ; Plant Shoots/microbiology ; Plant Stomata/physiology ; *Stress, Physiological ; Symbiosis ; },
abstract = {Arbuscular mycorrhizal (AM) symbiosis can alleviate drought and temperature stresses in plants, but it is unknown whether the benefits can be maintained when the plants are exposed to combined drought and heat stress. In this study, the impacts of AM fungi, Septoglomus deserticola and Septoglomus constrictum on tomato plant tolerance to combined drought and heat stress were investigated. No substantial differences in physiological parameters were found in all plants under non-stress conditions, except a higher expression of SlLOXD and SlPIP2.7 in plants + S. constrictum. Under drought, heat and drought + heat stress, both fungal symbionts could moderate oxidative stress by decreasing the lipid peroxidation, hydrogen peroxide level and improving leaf and root antioxidant enzyme activities, however better performance in plants + S. constrictum. Under drought and the combined stress, inoculation with S. constrictum enhanced stomatal conductance, leaf water potential and relative water content, elevated Fv/Fm and biomass production of the hosts as compared to non-inoculated plants whilst these improvements in plants + S. deserticola were not obvious. Under the combined stress inoculation of S. constrictum did not change the expression of SlNCED and SlPIP2.7 in roots as under heat stress. Expression of SlLOXD in root were upregulated in plants + S. contrictum under drought + heat stress as in mycorrhizal roots under drought stress. Altogether, our results indicated that AM inoculation, particularly with S. constrictum had a positive influence on the tomato plant tolerance to drought + heat stress. Further studies are essential to add some light on molecular mechanisms of mycorrhizal plant tolerance to this combined stress.},
}
@article {pmid30239843,
year = {2018},
author = {Hess, J and Skrede, I and Chaib De Mares, M and Hainaut, M and Henrissat, B and Pringle, A},
title = {Rapid Divergence of Genome Architectures Following the Origin of an Ectomycorrhizal Symbiosis in the Genus Amanita.},
journal = {Molecular biology and evolution},
volume = {35},
number = {11},
pages = {2786-2804},
doi = {10.1093/molbev/msy179},
pmid = {30239843},
issn = {1537-1719},
abstract = {Fungi are evolutionary shape shifters and adapt quickly to new environments. Ectomycorrhizal (EM) symbioses are mutualistic associations between fungi and plants and have evolved repeatedly and independently across the fungal tree of life, suggesting lineages frequently reconfigure genome content to take advantage of open ecological niches. To date analyses of genomic mechanisms facilitating EM symbioses have involved comparisons of distantly related species, but here, we use the genomes of three EM and two asymbiotic (AS) fungi from the genus Amanita as well as an AS outgroup to study genome evolution following a single origin of symbiosis. Our aim was to identify the defining features of EM genomes, but our analyses suggest no clear differentiation of genome size, gene repertoire size, or transposable element content between EM and AS species. Phylogenetic inference of gene gains and losses suggests the transition to symbiosis was dominated by the loss of plant cell wall decomposition genes, a confirmation of previous findings. However, the same dynamic defines the AS species A. inopinata, suggesting loss is not strictly associated with origin of symbiosis. Gene expansions in the common ancestor of EM Amanita were modest, but lineage specific and large gene family expansions are found in two of the three EM extant species. Even closely related EM genomes appear to share few common features. The genetic toolkit required for symbiosis appears already encoded in the genomes of saprotrophic species, and this dynamic may explain the pervasive, recurrent evolution of ectomycorrhizal associations.},
}
@article {pmid30238312,
year = {2018},
author = {Frare, R and Ayub, N and Alleva, K and Soto, G},
title = {The Ammonium Channel NOD26 is the Evolutionary Innovation that Drives the Emergence, Consolidation, and Dissemination of Nitrogen-Fixing Symbiosis in Angiosperms.},
journal = {Journal of molecular evolution},
volume = {86},
number = {8},
pages = {554-565},
doi = {10.1007/s00239-018-9867-3},
pmid = {30238312},
issn = {1432-1432},
support = {PICT-2015-0090//Agencia/ ; },
abstract = {Increasing evidence indicates that N-fixing symbiosis has evolved several times in the N-fixing clade of angiosperms and that this evolution is driven by a single evolutionary innovation. However, the genetics of this ancestral predisposition to N-fixing symbiosis remains unclear. A natural candidate for such molecular innovation is the ammonium channel NOD26, the main protein component of the symbiosome membrane, which facilitates the plant uptake of the nitrogen fixed by symbiotic bacteria. Here, in concordance with the emergence of N-fixing symbiosis in angiosperms but not in ancestral plants, phylogenetic analysis showed that NOD26 belongs to an angiosperm-exclusive subgroup of aquaporins. Integrated genomic, phylogenetic, and gene expression analyses supported NOD26 occurrence in the N-fixing clade, the increase in the NOD26 copy number by block and tandem duplications in legumes, and the low-copy number or even the loss of NOD26 in non-legume species of the N-fixing clade, which correlated with the possibility to lose N-fixing symbiosis in legume and non-legume lineages. Metabolic reconstructions showed that retention of NOD26 in N-fixing precursor could represent an adaptive mechanism to bypass energy crisis during anaerobic stress by ammonium detoxification. Finally, we discuss the potential use of NOD26 to transfer N-fixation to non-N-fixing crops as cereals.},
}
@article {pmid30237322,
year = {2018},
author = {García-Bayona, L and Comstock, LE},
title = {Bacterial antagonism in host-associated microbial communities.},
journal = {Science (New York, N.Y.)},
volume = {361},
number = {6408},
pages = {},
doi = {10.1126/science.aat2456},
pmid = {30237322},
issn = {1095-9203},
support = {R01 AI120633/AI/NIAID NIH HHS/United States ; R01 AI093771/AI/NIAID NIH HHS/United States ; },
mesh = {Animals ; Bacterial Infections/microbiology ; Bacterial Secretion Systems ; Bacterial Toxins/metabolism ; Bacteroides/physiology ; Gastrointestinal Microbiome ; Humans ; *Microbial Interactions ; *Microbiota ; Symbiosis ; },
abstract = {Antagonistic interactions are abundant in microbial communities and contribute not only to the composition and relative proportions of their members but also to the longer-term stability of a community. This Review will largely focus on bacterial antagonism mediated by ribosomally synthesized peptides and proteins produced by members of host-associated microbial communities. We discuss recent findings on their diversity, functions, and ecological impacts. These systems play key roles in ecosystem defense, pathogen invasion, spatial segregation, and diversity but also confer indirect gains to the aggressor from products released by killed cells. Investigations into antagonistic bacterial interactions are important for our understanding of how the microbiota establish within hosts, influence health and disease, and offer insights into potential translational applications.},
}
@article {pmid30236058,
year = {2018},
author = {Van Oosten, MJ and Di Stasio, E and Cirillo, V and Silletti, S and Ventorino, V and Pepe, O and Raimondi, G and Maggio, A},
title = {Root inoculation with Azotobacter chroococcum 76A enhances tomato plants adaptation to salt stress under low N conditions.},
journal = {BMC plant biology},
volume = {18},
number = {1},
pages = {205},
doi = {10.1186/s12870-018-1411-5},
pmid = {30236058},
issn = {1471-2229},
support = {FP7-KBBE-2012-6//Horizon 2020/ ; 727929//Horizon 2020/ ; },
mesh = {Adaptation, Physiological/*physiology ; Azotobacter/growth &amp; development/*physiology ; Gene Expression Regulation, Plant ; Lycopersicon esculentum/microbiology/*physiology ; Nitrogen/*metabolism ; Plant Leaves/physiology ; Plant Roots/*microbiology ; Rhizosphere ; Salt-Tolerance ; Symbiosis ; },
abstract = {BACKGROUND: The emerging roles of rhizobacteria in improving plant nutrition and stress protection have great potential for sustainable use in saline soils. We evaluated the function of the salt-tolerant strain Azotobacter chroococcum 76A as stress protectant in an important horticultural crop, tomato. Specifically we hypothesized that treatment of tomato plants with A. chroococcum 76A could improve plant performance under salinity stress and sub-optimal nutrient regimen.<br><br>RESULTS: Inoculation of Micro Tom tomato plants with A. chroococcum 76A increased numerous growth parameters and also conferred protective effects under both moderate (50 mM NaCl) and severe (100 mM NaCl) salt stresses. These benefits were mostly observed under reduced nutrient regimen and were less appreciable in optimal nitrogen conditions. Therefore, the efficiency of A. chroococcum 76A was found to be dependent on the nutrient status of the rhizosphere. The expression profiles of LEA genes indicated that A. chroococcum 76A treated plants were more responsive to stress stimuli when compared to untreated controls. However, transcript levels of key nitrogen assimilation genes revealed that the optimal nitrogen regimen, in combination with the strain A. chroococcum 76A, may have saturated plant's ability to assimilate nitrogen.<br><br>CONCLUSIONS: Roots inoculation with A. chroococcum 76A tomato promoted tomato plant growth, stress tolerance and nutrient assimilation efficiency under moderate and severe salinity. Inoculation with beneficial bacteria such as A. chroococcum 76A may be an ideal solution for low-input systems, where environmental constraints and limited chemical fertilization may affect the potential yield.},
}
@article {pmid30233618,
year = {2018},
author = {Bilal, S and Shahzad, R and Khan, AL and Kang, SM and Imran, QM and Al-Harrasi, A and Yun, BW and Lee, IJ},
title = {Endophytic Microbial Consortia of Phytohormones-Producing Fungus Paecilomyces formosus LHL10 and Bacteria Sphingomonas sp. LK11 to Glycine max L. Regulates Physio-hormonal Changes to Attenuate Aluminum and Zinc Stresses.},
journal = {Frontiers in plant science},
volume = {9},
number = {},
pages = {1273},
doi = {10.3389/fpls.2018.01273},
pmid = {30233618},
issn = {1664-462X},
abstract = {The compatible microbial consortia containing fungal and bacterial symbionts acting synergistically are applied to improve plant growth and eco-physiological responses in extreme crop growth conditions. However, the interactive effects of phytohormones-producing endophytic fungal and bacterial symbionts plant growth and stress tolerance under heavy metal stress have been least known. In the current study, the phytohormones-producing endophytic Paecilomyces formosus LHL10 and Sphingomonas sp. LK11 revealed potent growth and tolerance during their initial screening against combined Al and Zn (2.5 mM each) stress. This was followed with their co-inoculation in the Al- and Zn-stressed Glycine max L. plants, showing significantly higher plant growth attributes (shoot/root length, fresh/dry weight, and chlorophyll content) than the plants solely inoculated with LHL10 or LK11 and the non-inoculated (control) plants under metal stresses. Interestingly, under metal stress, the consortia exhibited lower metal uptake and inhibited metal transport in roots. Metal-induced oxidative stresses were modulated in co-inoculated plants through reduced hydrogen peroxide, lipid peroxidation, and antioxidant enzymes (catalase and superoxide dismutase) in comparison to the non-inoculated plants. In addition, endophytic co-inoculation enhanced plant macronutrient uptake (P, K, S, and N) and modulated soil enzymatic activities under stress conditions. It significantly downregulated the expression of heavy metal ATPase genes GmHMA13, GmHMA18, GmHMA19, and GmPHA1 and upregulated the expression of an ariadne-like ubiquitin ligase gene GmARI1 under heavy metals stress. Furthermore, the endogenous phytohormonal contents of co-inoculated plants revealed significantly enhanced gibberellins and reduced abscisic acid and jasmonic acid contents, suggesting that this endophytic interaction mitigated the adverse effect of metal stresses in host plants. In conclusion, the co-inoculation of the endophytic fungus LHL10 and bacteria LK11 actively contributed to the tripartite mutualistic symbiosis in G. max under heavy metal stresses; this could be used an excellent strategy for sustainable agriculture in the heavy metal-contaminated fields.},
}
@article {pmid30233616,
year = {2018},
author = {Chen, M and Arato, M and Borghi, L and Nouri, E and Reinhardt, D},
title = {Beneficial Services of Arbuscular Mycorrhizal Fungi - From Ecology to Application.},
journal = {Frontiers in plant science},
volume = {9},
number = {},
pages = {1270},
doi = {10.3389/fpls.2018.01270},
pmid = {30233616},
issn = {1664-462X},
abstract = {Arbuscular mycorrhiza (AM) is the most common symbiotic association of plants with microbes. AM fungi occur in the majority of natural habitats and they provide a range of important ecological services, in particular by improving plant nutrition, stress resistance and tolerance, soil structure and fertility. AM fungi also interact with most crop plants including cereals, vegetables, and fruit trees, therefore, they receive increasing attention for their potential use in sustainable agriculture. Basic research of the past decade has revealed the existence of a dedicated recognition and signaling pathway that is required for AM. Furthermore, recent evidence provided new insight into the exchange of nutritional benefits between the symbiotic partners. The great potential for application of AM has given rise to a thriving industry for AM-related products for agriculture, horticulture, and landscaping. Here, we discuss new developments in these fields, and we highlight future potential and limits toward the use of AM fungi for plant production.},
}
@article {pmid30233541,
year = {2018},
author = {Voß, S and Betz, R and Heidt, S and Corradi, N and Requena, N},
title = {RiCRN1, a Crinkler Effector From the Arbuscular Mycorrhizal Fungus Rhizophagus irregularis, Functions in Arbuscule Development.},
journal = {Frontiers in microbiology},
volume = {9},
number = {},
pages = {2068},
doi = {10.3389/fmicb.2018.02068},
pmid = {30233541},
issn = {1664-302X},
abstract = {Arbuscular mycorrhizal (AM) symbiosis is one of the most prominent and beneficial plant-microbe interactions that facilitates mineral nutrition and confers tolerance to biotic and abiotic stresses. AM fungi colonize the root cortex and develop specialized structures called arbuscules where the nutrient exchange takes place. Arbuscule development is a highly controlled and coordinated process requiring the involvement of many plant proteins recruited at that interface. In contrast, much less is known about the fungal proteins involved in this process. Here, we have identified an AM fungal effector that participates in this developmental step of the symbiosis. RiCRN1 is a crinkler (CRN) effector that belongs to a subfamily of secreted CRN proteins from R. irregularis. CRNs have been so far only functionally characterized in pathogenic microbes and shown to participate in processes controlling plant cell death and immunity. RiCRN1 accumulates during symbiosis establishment parallel to MtPT4, the gene coding for an arbuscule-specific phosphate transporter. Expression in Nicotiana benthamiana leaves and in Medicago truncatula roots suggest that RiCRN1 is not involved in cell death processes. RiCRN1 dimerizes and localizes to nuclear bodies, suggesting that, similar to other CRNs, it functions in the plant nucleus. Downregulation of RiCRN1 using host-induced gene silencing led to an impairment of the symbiosis in M. truncatula and to a reduction of MtPT4, while ectopic expression of RiCRN1, surprisingly, led to a drastic reduction in arbuscule size that correlated with a decrease not only in MtPT4 but also in MtBCP1, a marker for initial stages of arbuscule development. Altogether, our results suggest that a tightly regulated expression in time and space of RiCRN1 is critical for symbiosis progression and for the proper initiation of arbuscule development.},
}
@article {pmid30233528,
year = {2018},
author = {Clerissi, C and Brunet, S and Vidal-Dupiol, J and Adjeroud, M and Lepage, P and Guillou, L and Escoubas, JM and Toulza, E},
title = {Protists Within Corals: The Hidden Diversity.},
journal = {Frontiers in microbiology},
volume = {9},
number = {},
pages = {2043},
doi = {10.3389/fmicb.2018.02043},
pmid = {30233528},
issn = {1664-302X},
abstract = {Previous observations suggested that microbial communities contribute to coral health and the ecological resilience of coral reefs. However, most studies of coral microbiology focused on prokaryotes and the endosymbiotic algae Symbiodinium. In contrast, knowledge concerning diversity of other protists is still lacking, possibly due to methodological constraints. As most eukaryotic DNA in coral samples was derived from hosts, protist diversity was missed in metagenome analyses. To tackle this issue, we designed blocking primers for Scleractinia sequences amplified with two primer sets that targeted variable loops of the 18S rRNA gene (18SV1V2 and 18SV4). These blocking primers were used on environmental colonies of Pocillopora damicornis sensu lato from two regions with contrasting thermal regimes (Djibouti and New Caledonia). In addition to Symbiodinium clades A/C/D, Licnophora and unidentified coccidia genera were found in many samples. In particular, coccidian sequences formed a robust monophyletic clade with other protists identified in Agaricia, Favia, Montastraea, Mycetophyllia, Porites, and Siderastrea coral colonies. Moreover, Licnophora and coccidians had different distributions between the two geographic regions. A similar pattern was observed between Symbiodinium clades C and A/D. Although we were unable to identify factors responsible for this pattern, nor were we able to confirm that these taxa were closely associated with corals, we believe that these primer sets and the associated blocking primers offer new possibilities to describe the hidden diversity of protists within different coral species.},
}
@article {pmid30232679,
year = {2018},
author = {Gtari, M and Nouioui, I and Sarkar, I and Ghodhbane-Gtari, F and Tisa, LS and Sen, A and Klenk, HP},
title = {An update on the taxonomy of the genus Frankia Brunchorst, 1886, 174AL.},
journal = {Antonie van Leeuwenhoek},
volume = {},
number = {},
pages = {},
doi = {10.1007/s10482-018-1165-y},
pmid = {30232679},
issn = {1572-9699},
abstract = {Since the recognition of the name Frankia in the Approved Lists of bacterial names (1980), few amendments have been given to the genus description. Successive editions of Bergey's Manual of Systematics of Archaea and Bacteria have broadly conflicting suprageneric treatments of the genus without any advances for subgeneric classification. This review focuses on recent results from taxongenomics and phenoarray approaches to the positioning and the structuring of the genus Frankia. Based on phylogenomic analyses, Frankia should be considered the single member of the family Frankiaceae within the monophyletic order, Frankiales. A polyphasic strategy incorporating genome to genome data and omniLog® phenoarrays, together with classical approaches, has allowed the designation and an amended description of a type strain of the type species Frankia alni, and the recognition of at least 10 novel species covering symbiotic and non symbiotic taxa within the genus. Genome to phenome data will be shortly incorporated in the scheme for proposing novel species including those recalcitrant to isolation in axenic culture.},
}
@article {pmid30230652,
year = {2018},
author = {Little, MS and Ervin, SM and Walton, WG and Tripathy, A and Xu, Y and Liu, J and Redinbo, MR},
title = {Active site flexibility revealed in crystal structures of Parabacteroides merdae β-glucuronidase from the human gut microbiome.},
journal = {Protein science : a publication of the Protein Society},
volume = {27},
number = {12},
pages = {2010-2022},
doi = {10.1002/pro.3507},
pmid = {30230652},
issn = {1469-896X},
support = {CA098468CA207416//National Institutes of Health/ ; DGS-1650116//National Science Foundation/ ; },
abstract = {β-Glucuronidase (GUS) enzymes in the gastrointestinal tract are involved in maintaining mammalian-microbial symbiosis and can play key roles in drug efficacy and toxicity. Parabacteroides merdae GUS was identified as an abundant mini-Loop 2 (mL2) type GUS enzyme in the Human Microbiome Project gut metagenomic database. Here, we report the crystal structure of P. merdae GUS and highlight the differences between this enzyme and extant structures of gut microbial GUS proteins. We find that P. merdae GUS exhibits a distinct tetrameric quaternary structure and that the mL2 motif traces a unique path within the active site, which also includes two arginines distinctive to this GUS. We observe two states of the P. merdae GUS active site; a loop repositions itself by more than 50 Å to place a functionally-relevant residue into the enzyme's catalytic site. Finally, we find that P. merdae GUS is able to bind to homo and heteropolymers of the polysaccharide alginic acid. Together, these data broaden our understanding of the structural and functional diversity in the GUS family of enzymes present in the human gut microbiome and point to specialization as an important feature of microbial GUS orthologs.},
}
@article {pmid30229114,
year = {2018},
author = {Bharudin, I and Abdul Rahim, SN and Abu Bakar, MF and Ibrahim, SN and Kamaruddin, S and Latif, MT and Samsudin, MW and Abdul Murad, AM and Abu Bakar, FD},
title = {De novo transcriptome resources of the lichens, Dirinaria sp. UKM-J1 and UKM-K1 collected from Jerantut and Klang, Malaysia.},
journal = {Data in brief},
volume = {19},
number = {},
pages = {2416-2419},
doi = {10.1016/j.dib.2018.07.020},
pmid = {30229114},
issn = {2352-3409},
abstract = {Lichen is a symbiotic organism that exists as a single composite body consisting of a mycobiont (fungus) and a photobiont (algae or a cyanobacterium). Many lichen species are considered as extremophiles due to their tolerance to radiation, desiccation, temperature and pollution. However, not all lichen species are tolerant to harsh environmental conditions as several species are sensitive for example to nitrogen, sulphur, acidity, heavy metals, halogens (e.g. fluoride) and ozone. Thus, to better understand why some lichens can withstand exposure to pollutants as opposed to those that are susceptible, we focused on the lichen species of Dirinaria known for their wide distribution in the tropics, subtropics and pantropical, and moderate tolerance to air pollution. Their moderate tolerance to air pollution affords them to thrive in good air quality environments as well as polluted air environments. Lichen samples of Dirinaria sp., UKM-J1 and UKM-K1, were respectively collected from two areas with different levels of air quality based on Air Pollutant Index or API (with index pollutant criteria of PM10, carbon monoxide, ozone, nitrogen dioxide and sulfur dioxide) in the outskirt of Jerantut (UKM-J1), a rural area in the middle of Peninsular Malaysia and the township of Klang (UKM-K1), in a busy area of the Klang Valley, Malaysia. API was monitored throughout 2012-2013 whereby the sample collection site in Klang showed markedly higher concentrations of pollutants in all the index pollutant criteria as compared to that of Jerantut. We performed transcriptome sequencing using Illumina RNA-seq technology and de novo assembly of the transcripts from the lichen samples. Raw reads from both libraries were deposited in the NCBI database with the accession number SRP138994.},
}
@article {pmid30227634,
year = {2018},
author = {White, JF and Kingsley, KL and Verma, SK and Kowalski, KP},
title = {Rhizophagy Cycle: An Oxidative Process in Plants for Nutrient Extraction from Symbiotic Microbes.},
journal = {Microorganisms},
volume = {6},
number = {3},
pages = {},
doi = {10.3390/microorganisms6030095},
pmid = {30227634},
issn = {2076-2607},
support = {G16AC00433//U.S. Geological Survey/ ; W3157//U.S. Department of Agriculture/ ; },
abstract = {In this paper, we describe a mechanism for the transfer of nutrients from symbiotic microbes (bacteria and fungi) to host plant roots that we term the 'rhizophagy cycle.' In the rhizophagy cycle, microbes alternate between a root intracellular endophytic phase and a free-living soil phase. Microbes acquire soil nutrients in the free-living soil phase; nutrients are extracted through exposure to host-produced reactive oxygen in the intracellular endophytic phase. We conducted experiments on several seed-vectored microbes in several host species. We found that initially the symbiotic microbes grow on the rhizoplane in the exudate zone adjacent the root meristem. Microbes enter root tip meristem cells-locating within the periplasmic spaces between cell wall and plasma membrane. In the periplasmic spaces of root cells, microbes convert to wall-less protoplast forms. As root cells mature, microbes continue to be subjected to reactive oxygen (superoxide) produced by NADPH oxidases (NOX) on the root cell plasma membranes. Reactive oxygen degrades some of the intracellular microbes, also likely inducing electrolyte leakage from microbes-effectively extracting nutrients from microbes. Surviving bacteria in root epidermal cells trigger root hair elongation and as hairs elongate bacteria exit at the hair tips, reforming cell walls and cell shapes as microbes emerge into the rhizosphere where they may obtain additional nutrients. Precisely what nutrients are transferred through rhizophagy or how important this process is for nutrient acquisition is still unknown.},
}
@article {pmid30223889,
year = {2018},
author = {Jarett, JK and Nayfach, S and Podar, M and Inskeep, W and Ivanova, NN and Munson-McGee, J and Schulz, F and Young, M and Jay, ZJ and Beam, JP and Kyrpides, NC and Malmstrom, RR and Stepanauskas, R and Woyke, T},
title = {Single-cell genomics of co-sorted Nanoarchaeota suggests novel putative host associations and diversification of proteins involved in symbiosis.},
journal = {Microbiome},
volume = {6},
number = {1},
pages = {161},
doi = {10.1186/s40168-018-0539-8},
pmid = {30223889},
issn = {2049-2618},
support = {DE-AC02-05CH11231//U.S. Department of Energy/ ; DEB-1441717//National Science Foundation/ ; OCe-1335810//National Science Foundation/ ; },
abstract = {BACKGROUND: Nanoarchaeota are obligate symbionts of other Archaea first discovered 16 years ago, yet little is known about this largely uncultivated taxon. While Nanoarchaeota diversity has been detected in a variety of habitats using 16S rRNA gene surveys, genome sequences have been available for only three Nanoarchaeota and their hosts. The host range and adaptation of Nanoarchaeota to a wide range of environmental conditions has thus largely remained elusive. Single-cell genomics is an ideal approach to address these questions as Nanoarchaeota can be isolated while still attached to putative hosts, enabling the exploration of cell-cell interactions and fine-scale genomic diversity.<br><br>RESULTS: From 22 single amplified genomes (SAGs) from three hot springs in Yellowstone National Park, we derived a genome-based phylogeny of the phylum Nanoarchaeota, linking it to global 16S rRNA gene diversity. By exploiting sequencing of co-sorted tightly attached cells, we associated Nanoarchaeota with 6 novel putative hosts, 2 of which were found in multiple SAGs, and showed that the same host species may associate with multiple species of Nanoarchaeota. Comparison of single nucleotide polymorphisms (SNPs) within a population of Nanoarchaeota SAGs indicated that Nanoarchaeota attached to a single host cell in situ are likely clonal. In addition to an overall pattern of purifying selection, we found significantly higher densities of non-synonymous SNPs in hypothetical cell surface proteins, as compared to other functional categories. Genes implicated in interactions in other obligate microbe-microbe symbioses, including those encoding a cytochrome bd-I ubiquinol oxidase and a FlaJ/TadC homologue possibly involved in type IV pili production, also had relatively high densities of non-synonymous SNPs.<br><br>CONCLUSIONS: This population genetics study of Nanoarchaeota greatly expands the known potential host range of the phylum and hints at what genes may be involved in adaptation to diverse environments or different hosts. We provide the first evidence that Nanoarchaeota cells attached to the same host cell are clonal and propose a hypothesis for how clonality may occur despite diverse symbiont populations.},
}
@article {pmid30223644,
year = {2018},
author = {Checcucci, A and diCenzo, GC and Ghini, V and Bazzicalupo, M and Becker, A and Decorosi, F and Döhlemann, J and Fagorzi, C and Finan, TM and Fondi, M and Luchinat, C and Turano, P and Vignolini, T and Viti, C and Mengoni, A},
title = {Creation and Characterization of a Genomically Hybrid Strain in the Nitrogen-Fixing Symbiotic Bacterium Sinorhizobium meliloti.},
journal = {ACS synthetic biology},
volume = {7},
number = {10},
pages = {2365-2378},
doi = {10.1021/acssynbio.8b00158},
pmid = {30223644},
issn = {2161-5063},
abstract = {Many bacteria, often associated with eukaryotic hosts and of relevance for biotechnological applications, harbor a multipartite genome composed of more than one replicon. Biotechnologically relevant phenotypes are often encoded by genes residing on the secondary replicons. A synthetic biology approach to developing enhanced strains for biotechnological purposes could therefore involve merging pieces or entire replicons from multiple strains into a single genome. Here we report the creation of a genomic hybrid strain in a model multipartite genome species, the plant-symbiotic bacterium Sinorhizobium meliloti. We term this strain as cis-hybrid, since it is produced by genomic material coming from the same species' pangenome. In particular, we moved the secondary replicon pSymA (accounting for nearly 20% of total genome content) from a donor S. meliloti strain to an acceptor strain. The cis-hybrid strain was screened for a panel of complex phenotypes (carbon/nitrogen utilization phenotypes, intra- and extracellular metabolomes, symbiosis, and various microbiological tests). Additionally, metabolic network reconstruction and constraint-based modeling were employed for in silico prediction of metabolic flux reorganization. Phenotypes of the cis-hybrid strain were in good agreement with those of both parental strains. Interestingly, the symbiotic phenotype showed a marked cultivar-specific improvement with the cis-hybrid strains compared to both parental strains. These results provide a proof-of-principle for the feasibility of genome-wide replicon-based remodelling of bacterial strains for improved biotechnological applications in precision agriculture.},
}
@article {pmid30222191,
year = {2018},
author = {Montero, H and Choi, J and Paszkowski, U},
title = {Arbuscular mycorrhizal phenotyping: the dos and don'ts.},
journal = {The New phytologist},
volume = {},
number = {},
pages = {},
doi = {10.1111/nph.15489},
pmid = {30222191},
issn = {1469-8137},
support = {//CONICYT Chile-Cambridge TRUST/ ; ECF-2016-392//Leverhulme Early Career Fellowship/ ; //The Leverhulme Trust, UK/ ; BB/P003419/1//Biotechnology and Biological Sciences Research Council (BBSRC)/ ; BB/N008723/1//Biotechnology and Biological Sciences Research Council (BBSRC)/ ; },
}
@article {pmid30219638,
year = {2018},
author = {Cremon, C and Barbaro, MR and Ventura, M and Barbara, G},
title = {Pre- and probiotic overview.},
journal = {Current opinion in pharmacology},
volume = {43},
number = {},
pages = {87-92},
doi = {10.1016/j.coph.2018.08.010},
pmid = {30219638},
issn = {1471-4973},
abstract = {The dynamic relationship between gut microbiota and its human host is also known as a trophic association that might range from commensalism, where only the microbe enjoys a positive effect from the relationship, to intestinal symbiosis where both host and microbe benefit from their interaction. In the last years, we have started to understand how alterations of the gut microbiota composition leading to the disruption of host-microbial interactions are associated and/or predispose individuals to disease conditions ranging from inflammatory bowel diseases to allergy and functional gastrointestinal disorders, such as irritable bowel syndrome. While we await important insights in this field, the microbiota is already a therapeutic target. Based on the actual definitions, prebiotics are defined as substrates that are selectively utilized by host microorganisms conferring a health benefit, while probiotics are live microorganisms that, when administered in adequate amounts, confer a health benefit on the host. Although their health promoting activities encompasses numerous effects, including immunostimulation, competitive exclusion of pathogens, and gut barrier enhancement, the exact mechanism of action by which these compounds exert their beneficial actions in humans is only partially known. In this review, we highlight the current insights into the clinical applications of prebiotics and probiotics in gastroenterology.},
}
@article {pmid30218020,
year = {2018},
author = {Porter, SS and Faber-Hammond, J and Montoya, AP and Friesen, ML and Sackos, C},
title = {Dynamic genomic architecture of mutualistic cooperation in a wild population of Mesorhizobium.},
journal = {The ISME journal},
volume = {},
number = {},
pages = {},
doi = {10.1038/s41396-018-0266-y},
pmid = {30218020},
issn = {1751-7370},
abstract = {Research on mutualism seeks to explain how cooperation can be maintained when uncooperative mutants co-occur with cooperative kin. Gains and losses of the gene modules required for cooperation punctuate symbiont phylogenies and drive lifestyle transitions between cooperative symbionts and uncooperative free-living lineages over evolutionary time. Yet whether uncooperative symbionts commonly evolve from within cooperative symbiont populations or from within distantly related lineages with antagonistic or free-living lifestyles (i.e., third-party mutualism exploiters or parasites), remains controversial. We use genomic data to show that genotypes that differ in the presence or absence of large islands of symbiosis genes are common within a single wild recombining population of Mesorhizobium symbionts isolated from host tissues and are an important source of standing heritable variation in cooperation in this population. In a focal population of Mesorhizobium, uncooperative variants that lack a symbiosis island segregate at 16% frequency in nodules, and genome size and symbiosis gene number are positively correlated with cooperation. This finding contrasts with the genomic architecture of variation in cooperation in other symbiont populations isolated from host tissues in which the islands of genes underlying cooperation are ubiquitous and variation in cooperation is primarily driven by allelic substitution and individual gene gain and loss events. Our study demonstrates that uncooperative mutants within mutualist populations can comprise a significant component of genetic variation in nature, providing biological rationale for models and experiments that seek to explain the maintenance of mutualism in the face of non-cooperators.},
}
@article {pmid30217853,
year = {2018},
author = {Schwob, G and Roy, M and Pozzi, AC and Herrera-Belaroussi, A and Fernandez, MP},
title = {In Planta Sporulation of Frankia spp. as a Determinant of Alder-Symbiont Interactions.},
journal = {Applied and environmental microbiology},
volume = {84},
number = {23},
pages = {},
doi = {10.1128/AEM.01737-18},
pmid = {30217853},
issn = {1098-5336},
abstract = {The Alnus genus forms symbiosis with the actinobacteria Frankia spp. and ectomycorrhizal fungi. Two types of Frankia lineages can be distinguished based on their ability to sporulate in planta Spore-positive (Sp+) strains are predominant on Alnus incana and Alnus viridis in highlands, while spore-negative (Sp-) strains are mainly associated with Alnus glutinosa in lowlands. Here, we investigated whether the Sp+ predominance in nodules is due to host selection of certain Frankia genotypes from soil communities or the result of the ecological history of the alder stand soil, as well as the effect of the sporulation genotype on the ectomycorrhizal (ECM) communities. Trapping experiments were conducted using A. glutinosa, A. incana, and A. viridis plantlets on 6 soils, differing in the alder species and the frequency of Sp+ nodules in the field. Higher diversity of Frankia spp. and variation in Sp+ frequencies were observed in the trapping than in the fields. Both indigenous and trapping species shape Frankia community structure in trapped nodules. Nodulation impediments were observed under several trapping conditions in Sp+ soils, supporting a narrower host range of Sp+ Frankia species. A. incana and A. viridis were able to associate equally with compatible Sp+ and Sp- strains in the greenhouse. Additionally, no host shift was observed for Alnus-specific ECM, and the sporulation genotype of Frankia spp. defined the ECM communities on the host roots. The symbiotic association is likely determined by the host range, the soil history, and the type of in plantaFrankia species. These results provide an insight into the biogeographical drivers of alder symbionts in the Holarctic region.IMPORTANCE Most Frankia-actinorhiza plant symbioses are capable of high rates of nitrogen fixation comparable to those found on legumes. Yet, our understanding of the ecology and distribution of Frankia spp. is still very limited. Several studies have focused on the distribution patterns of Frankia spp., demonstrating a combination of host and pedoclimatic parameters in their biogeography. However, very few have considered the in planta sporulation form of the strain, although it is a unique feature among all symbiotic plant-associated microbes. Compared with Sp- Frankia strains, Sp+ strains would be obligate symbionts that are highly dependent on the presence of a compatible host species and with lower efficiency in nitrogen fixation. Understanding the biogeographical drivers of Sp+ Frankia strains might help elucidate the ecological role of in planta sporulation and the extent to which this trait mediates host-partner interactions in the alder-Frankia-ECM fungal symbiosis.},
}
@article {pmid30217010,
year = {2018},
author = {Benndorf, R and Guo, H and Sommerwerk, E and Weigel, C and Garcia-Altares, M and Martin, K and Hu, H and Küfner, M and de Beer, ZW and Poulsen, M and Beemelmanns, C},
title = {Natural Products from Actinobacteria Associated with Fungus-Growing Termites.},
journal = {Antibiotics (Basel, Switzerland)},
volume = {7},
number = {3},
pages = {},
doi = {10.3390/antibiotics7030083},
pmid = {30217010},
issn = {2079-6382},
support = {CRC 1127, BE-4799/3-1//Deutsche Forschungsgemeinschaft/ ; VKR10101//Villum Kann Rasmussen Foundation/ ; },
abstract = {The chemical analysis of insect-associated Actinobacteria has attracted the interest of natural product chemists in the past years as bacterial-produced metabolites are sought to be crucial for sustaining and protecting the insect host. The objective of our study was to evaluate the phylogeny and bioprospecting of Actinobacteria associated with fungus-growing termites. We characterized 97 Actinobacteria from the gut, exoskeleton, and fungus garden (comb) of the fungus-growing termite Macrotermes natalensis and used two different bioassays to assess their general antimicrobial activity. We selected two strains for chemical analysis and investigated the culture broth of the axenic strains and fungus-actinobacterium co-cultures. From these studies, we identified the previously-reported PKS-derived barceloneic acid A and the PKS-derived rubterolones. Analysis of culture broth yielded a new dichlorinated diketopiperazine derivative and two new tetracyclic lanthipeptides, named rubrominins A and B. The discussed natural products highlight that insect-associated Actinobacteria are highly prolific natural product producers yielding important chemical scaffolds urgently needed for future drug development programs.},
}
@article {pmid30216955,
year = {2018},
author = {Tsuji, K and Fukami, T},
title = {Community-wide consequences of sexual dimorphism: evidence from nectar microbes in dioecious plants.},
journal = {Ecology},
volume = {99},
number = {11},
pages = {2476-2484},
doi = {10.1002/ecy.2494},
pmid = {30216955},
issn = {0012-9658},
support = {25451//JSPS fellows/ ; 40645280//Young Scientist/ ; //Kyoto University Foundation/ ; //Stanford University's Office of International Affairs/ ; },
abstract = {Intraspecific trait variation is receiving renewed interest as a factor affecting the structure of multi-species communities within and across trophic levels. One pervasive form of intraspecific trait variation is sexual dimorphism in animals and plants, which might exert large effects particularly on the communities of host-associated organisms, but the extent of these effects is not well understood. We investigated whether host-associated microbial communities developed differently in the floral nectar of female and male individuals of the dioecious shrubs, Eurya emarginata and E. japonica. We found that nectar-colonizing microbes such as bacteria and fungi were more than twice as prevalent and, overall, more than 10 times as abundant in male flowers as in female flowers. Microbial species composition also differed between flower sexes. To examine potential mechanisms behind these differences, we manipulated the frequency of flower visitation by animals and the order of arrival of microbial species to nectar. Animal visitation frequency affected microbial communities more greatly in male flowers, while arrival order affected them more in female flowers. These sex-specific effects appeared attributable to differences in how animals and microbes altered the chemical characteristics of nectar that limited microbial growth. Taken together, our results provide evidence that sexual dimorphism can have large effects on the structure of host-associated communities.},
}
@article {pmid30215182,
year = {2018},
author = {Vasilchenko, AS and Gritsenko, VA and Kosyan, DB and Rogozhin, EA},
title = {A Low-Molecular-Weight Compound Derived from Human Leukocytes Determines a Bactericidal Activity of the Interferon Preparation.},
journal = {Probiotics and antimicrobial proteins},
volume = {},
number = {},
pages = {},
doi = {10.1007/s12602-018-9463-2},
pmid = {30215182},
issn = {1867-1314},
abstract = {The aim of this study was to characterize the structure and mode of action of antimicrobials derived from a commercial preparation of alfa-interferon. By combination of semi-preparative/analytical reversed-phase high-performance liquid chromatography, we isolated and purified a novel active substance based on carbohydrate with a complex of amino acids, which determines antimicrobial property of commercial preparation of interferon. A size-exclusion chromatography was performed and LC/ESI-MS revealed molecular masses of active substance were in the range of 180-249 Da. Edman sequencing identified phenylthiohydantoin (PTH) derivatives which consisted a set of preliminary (Asp, Glu, Gly, and Ala) and minor amino acids (Leu and Thr) at equimolar ratio. Thus, the purified active substance is a compound containing the complex of amino acids connected with carbohydrate background and called leucidin. Leucidin demonstrated antimicrobial activity against the model Escherichia coli (E. coli) K12 strain at a minimal inhibitory concentration of 20 μg mL-1. The revealed antimicrobial mechanism of action is associated with violation of the bacterial cell wall leading to a SOS response and bacterial autolysis. Despite the preliminary nature of the results, obtained data allowed us to discover the previously unknown leukocyte-derived antimicrobial molecules.},
}
@article {pmid30210532,
year = {2018},
author = {Saramago, M and Robledo, M and Matos, RG and Jiménez-Zurdo, JI and Arraiano, CM},
title = {Sinorhizobium meliloti RNase III: Catalytic Features and Impact on Symbiosis.},
journal = {Frontiers in genetics},
volume = {9},
number = {},
pages = {350},
doi = {10.3389/fgene.2018.00350},
pmid = {30210532},
issn = {1664-8021},
abstract = {Members of the ribonuclease (RNase) III family of enzymes are metal-dependent double-strand specific endoribonucleases. They are ubiquitously found and eukaryotic RNase III-like enzymes include Dicer and Drosha, involved in RNA processing and RNA interference. In this work, we have addressed the primary characterization of RNase III from the symbiotic nitrogen-fixing α-proteobacterium Sinorhizobium meliloti. The S. meliloti rnc gene does encode an RNase III-like protein (SmRNase III), with recognizable catalytic and double-stranded RNA (dsRNA)-binding domains that clusters in a branch with its α-proteobacterial counterparts. Purified SmRNase III dimerizes, is active at neutral to alkaline pH and behaves as a strict metal cofactor-dependent double-strand endoribonuclease, with catalytic features distinguishable from those of the prototypical member of the family, the Escherichia coli ortholog (EcRNase III). SmRNase III prefers Mn2+ rather than Mg2+ as metal cofactor, cleaves the generic structured R1.1 substrate at a site atypical for RNase III cleavage, and requires higher cofactor concentrations and longer dsRNA substrates than EcRNase III for optimal activity. Furthermore, the ultraconserved E125 amino acid was shown to play a major role in the metal-dependent catalysis of SmRNase III. SmRNase III degrades endogenous RNA substrates of diverse biogenesis with different efficiency, and is involved in the maturation of the 23S rRNA. SmRNase III loss-of-function neither compromises viability nor alters morphology of S. meliloti cells, but influences growth, nodulation kinetics, the onset of nitrogen fixation and the overall symbiotic efficiency of this bacterium on the roots of its legume host, alfalfa, which ultimately affects plant growth. Our results support an impact of SmRNase III on nodulation and symbiotic nitrogen fixation in plants.},
}
@article {pmid30210473,
year = {2018},
author = {Mars Brisbin, M and Mesrop, LY and Grossmann, MM and Mitarai, S},
title = {Intra-host Symbiont Diversity and Extended Symbiont Maintenance in Photosymbiotic Acantharea (Clade F).},
journal = {Frontiers in microbiology},
volume = {9},
number = {},
pages = {1998},
doi = {10.3389/fmicb.2018.01998},
pmid = {30210473},
issn = {1664-302X},
abstract = {Photosymbiotic protists contribute to surface primary production in low-nutrient, open-ocean ecosystems and constitute model systems for studying plastid acquisition via endosymbiosis. Little is known, however, about host-symbiont dynamics in these important relationships, and whether these symbioses are mutualistic is debated. In this study, we applied single-cell sequencing methods and advanced fluorescent microscopy to investigate host-symbiont dynamics in clade F acantharians, a major group of photosymbiotic protists in oligotrophic subtropical gyres. We amplified the 18S rRNA gene from single acantharian hosts and environmental samples to assess intra-host symbiont diversity and to determine whether intra-host symbiont community composition directly reflects the available symbiont community in the surrounding environment. Our results demonstrate that clade F acantharians simultaneously host multiple species from the haptophyte genera Phaeocystis and Chrysochromulina. The intra-host symbiont community composition was distinct from the external free-living symbiont community, suggesting that these acantharians maintain symbionts for extended periods of time. After selectively staining digestive organelles, fluorescent confocal microscopy showed that symbionts were not being systematically digested, which is consistent with extended symbiont maintenance within hosts. Extended maintenance within hosts may benefit symbionts through protection from grazing or viral lysis, and therefore could enhance dispersal, provided that symbionts retain reproductive capacity. The evidence for extended symbiont maintenance therefore allows that Phaeocystis could glean some advantage from the symbiosis and leaves the possibility of mutualism.},
}
@article {pmid30209475,
year = {2018},
author = {Niehs, SP and Scherlach, K and Hertweck, C},
title = {Genomics-driven discovery of a linear lipopeptide promoting host colonization by endofungal bacteria.},
journal = {Organic &amp; biomolecular chemistry},
volume = {16},
number = {37},
pages = {8345-8352},
doi = {10.1039/c8ob01515e},
pmid = {30209475},
issn = {1477-0539},
abstract = {The rice seedling blight fungus Rhizopus microsporus weakens or kills plants by means of a potent toxin produced by endobacteria (Burkholderia rhizoxinica) that live within the fungal hyphae. The success of the highly attuned microbial interaction is partly based on the bacteria's ability to roam and re-colonize the fungal host. Yet, apart from the toxin, chemical mediators of the symbiosis have remained elusive. By genome mining and comparison we identified a cryptic NRPS gene cluster that is conserved among all sequenced Rhizopus endosymbionts. Metabolic profiling and targeted gene inactivation led to the discovery of a novel linear lipopeptide, holrhizin A, which was fully characterized. Through in vitro and in vivo assays we found that holrhizin acts (A) as a biosurfactant to reduce surface tension, (B) influences the formation of mature biofilms and thus cell motility behavior that ultimately supports the bacterial cells to (C) colonize and invade the fungal host, consequently supporting the re-establishment of the exceptional Burkholderia-Rhizopus symbiosis. We not only unveil structure and function of an linear lipopeptide from endofungal bacteria but also provide a functional link between the symbiont's orphan NRPS genes and a chemical mediator that promotes bacterial invasion into the fungal host.},
}
@article {pmid30209216,
year = {2018},
author = {Xue, L and Klinnawee, L and Zhou, Y and Saridis, G and Vijayakumar, V and Brands, M and Dörmann, P and Gigolashvili, T and Turck, F and Bucher, M},
title = {AP2 transcription factor CBX1 with a specific function in symbiotic exchange of nutrients in mycorrhizal Lotus japonicus.},
journal = {Proceedings of the National Academy of Sciences of the United States of America},
volume = {115},
number = {39},
pages = {E9239-E9246},
doi = {10.1073/pnas.1812275115},
pmid = {30209216},
issn = {1091-6490},
mesh = {Fungal Proteins/*metabolism ; Loteae/genetics/*metabolism/microbiology ; Mycorrhizae/genetics/*metabolism ; Phosphate Transport Proteins/metabolism ; Phosphates/metabolism ; Proton-Translocating ATPases/metabolism ; *Symbiosis/genetics ; Transcription Factors/*metabolism ; },
abstract = {The arbuscular mycorrhizal (AM) symbiosis, a widespread mutualistic association between land plants and fungi, depends on reciprocal exchange of phosphorus driven by proton-coupled phosphate uptake into host plants and carbon supplied to AM fungi by host-dependent sugar and lipid biosynthesis. The molecular mechanisms and cis-regulatory modules underlying the control of phosphate uptake and de novo fatty acid synthesis in AM symbiosis are poorly understood. Here, we show that the AP2 family transcription factor CTTC MOTIF-BINDING TRANSCRIPTION FACTOR1 (CBX1), a WRINKLED1 (WRI1) homolog, directly binds the evolutionary conserved CTTC motif that is enriched in mycorrhiza-regulated genes and activates Lotus japonicus phosphate transporter 4 (LjPT4) in vivo and in vitro. Moreover, the mycorrhiza-inducible gene encoding H+-ATPase (LjHA1), implicated in energizing nutrient uptake at the symbiotic interface across the periarbuscular membrane, is coregulated with LjPT4 by CBX1. Accordingly, CBX1-defective mutants show reduced mycorrhizal colonization. Furthermore, genome-wide-binding profiles, DNA-binding studies, and heterologous expression reveal additional binding of CBX1 to AW box, the consensus DNA-binding motif for WRI1, that is enriched in promoters of glycolysis and fatty acid biosynthesis genes. We show that CBX1 activates expression of lipid metabolic genes including glycerol-3-phosphate acyltransferase RAM2 implicated in acylglycerol biosynthesis. Our finding defines the role of CBX1 as a regulator of host genes involved in phosphate uptake and lipid synthesis through binding to the CTTC/AW molecular module, and supports a model underlying bidirectional exchange of phosphorus and carbon, a fundamental trait in the mutualistic AM symbiosis.},
}
@article {pmid30205015,
year = {2018},
author = {diCenzo, GC and Zamani, M and Checcucci, A and Fondi, M and Griffitts, JS and Finan, TM and Mengoni, A},
title = {Multidisciplinary approaches for studying rhizobium-legume symbioses.},
journal = {Canadian journal of microbiology},
volume = {},
number = {},
pages = {1-33},
doi = {10.1139/cjm-2018-0377},
pmid = {30205015},
issn = {1480-3275},
abstract = {The rhizobium-legume symbiosis is a major source of fixed nitrogen (ammonia) in the biosphere. The potential for this process to increase agricultural yield while reducing the reliance on nitrogen-based fertilizers has generated interest in understanding and manipulating this process. For decades, rhizobium research has benefited from the use of leading techniques from a very broad set of fields, including population genetics, molecular genetics, genomics, and systems biology. In this review, we summarize many of the research strategies that have been employed in the study of rhizobia and the unique knowledge gained from these diverse tools, with a focus on genome- and systems-level approaches. We then describe ongoing synthetic biology approaches aimed at improving existing symbioses or engineering completely new symbiotic interactions. The review concludes with our perspective of the future directions and challenges of the field, with an emphasis on how the application of a multidisciplinary approach and the development of new methods will be necessary to ensure successful biotechnological manipulation of the symbiosis.},
}
@article {pmid30204748,
year = {2018},
author = {Kaur, N and Cooper, WR and Duringer, JM and Badillo-Vargas, IE and Esparza-Díaz, G and Rashed, A and Horton, DR},
title = {Survival and development of potato psyllid (Hemiptera: Triozidae) on Convolvulaceae: Effects of a plant-fungus symbiosis (Periglandula).},
journal = {PloS one},
volume = {13},
number = {9},
pages = {e0201506},
doi = {10.1371/journal.pone.0201506},
pmid = {30204748},
issn = {1932-6203},
abstract = {Plant species in the family Solanaceae are the usual hosts of potato psyllid, Bactericera cockerelli (Šulc) (Hemiptera: Psylloidea: Triozidae). However, the psyllid has also been shown to develop on some species of Convolvulaceae (bindweeds and morning glories). Developmental success on Convolvulaceae is surprising given the rarity of psyllid species worldwide associated with this plant family. We assayed 14 species of Convolvulaceae across four genera (Convolvulus, Calystegia, Ipomoea, Turbina) to identify species that allow development of potato psyllid. Two populations of psyllids were assayed (Texas, Washington). The Texas population overlaps extensively with native Convolvulaceae, whereas Washington State is noticeably lacking in Convolvulaceae. Results of assays were overlain on a phylogenetic analysis of plant species to examine whether Convolvulaceae distantly related to the typical host (potato) were less likely to allow development than species of Convolvulaceae more closely related. Survival was independent of psyllid population and location of the plant species on our phylogenetic tree. We then examined whether presence of a fungal symbiont of Convolvulaceae (Periglandula spp.) affected psyllid survival. These fungi associate with Convolvulaceae and produce a class of mycotoxins (ergot alkaloids) that may confer protection against plant-feeding arthropods. Periglandula was found in 11 of our 14 species, including in two genera (Convolvulus, Calystegia) not previously known to host the symbiont. Of these 11 species, leaf tissues from five contained large quantities of two classes of ergot alkaloids (clavines, amides of lysergic acid) when evaluated by LC-MS/MS. All five species also harbored Periglandula. No ergot alkaloids were detected in species free of the fungal symbiont. Potato psyllid rapidly died on the five species that harbored Periglandula and contained ergot alkaloids, but survived to adulthood on seven of the nine species in which ergot alkaloids were not detected. These results support the hypothesis that a plant-fungus symbiotic relationship affects the suitability of certain Convolvulaceae to potato psyllid.},
}
@article {pmid30203358,
year = {2018},
author = {Ghodhbane-Gtari, F and Nouioui, I and Hezbri, K and Lundstedt, E and D'Angelo, T and McNutt, Z and Laplaze, L and Gherbi, H and Vaissayre, V and Svistoonoff, S and Ahmed, HB and Boudabous, A and Tisa, LS},
title = {The plant-growth-promoting actinobacteria of the genus Nocardia induces root nodule formation in Casuarina glauca.},
journal = {Antonie van Leeuwenhoek},
volume = {},
number = {},
pages = {},
doi = {10.1007/s10482-018-1147-0},
pmid = {30203358},
issn = {1572-9699},
support = {2015-67014-22849//National Institute of Food and Agriculture/ ; 02281//National Institute of Food and Agriculture/ ; Summer Undergraduate Research Fellowship//University of New Hampshire/ ; 09G0916//Comite Mixte Tuniso-Francais pour la Cooperation inter-Universitaire/ ; NH AES Postdoctoral Fellow Program//College of Life Sciences and Agriculture, University of New Hampshire/ ; },
abstract = {Actinorhizal plants form a symbiotic association with the nitrogen-fixing actinobacteria Frankia. These plants have important economic and ecological benefits including land reclamation, soil stabilization, and reforestation. Recently, many non-Frankia actinobacteria have been isolated from actinorhizal root nodules suggesting that they might contribute to nodulation. Two Nocardia strains, BMG51109 and BMG111209, were isolated from Casuarina glauca nodules, and they induced root nodule-like structures in original host plant promoting seedling growth. The formed root nodule-like structures lacked a nodular root at the apex, were not capable of reducing nitrogen and had their cortical cells occupied with rod-shaped Nocardiae cells. Both Nocardia strains induced root hair deformation on the host plant. BMG111209 strain induced the expression of the ProCgNin:Gus gene, a plant gene involved in the early steps of the infection process and nodulation development. Nocardia strain BMG51109 produced three types of auxins (Indole-3-acetic acid [IAA], Indole-3-Byturic Acid [IBA] and Phenyl Acetic Acid [PAA]), while Nocardia BMG111209 only produced IAA. Analysis of the Nocardia genomes identified several important predicted biosynthetic gene clusters for plant phytohormones, secondary metabolites, and novel natural products. Co-infection studies showed that Nocardia strain BMG51109 plays a role as a &quot;helper bacteria&quot; promoting an earlier onset of nodulation. This study raises many questions on the ecological significance and functionality of Nocardia bacteria in actinorhizal symbioses.},
}
@article {pmid30203337,
year = {2018},
author = {Bizarria, R and Moia, IC and Montoya, QV and Polezel, DA and Rodrigues, A},
title = {Soluble Compounds of Filamentous Fungi Harm the Symbiotic Fungus of Leafcutter Ants.},
journal = {Current microbiology},
volume = {75},
number = {12},
pages = {1602-1608},
doi = {10.1007/s00284-018-1566-1},
pmid = {30203337},
issn = {1432-0991},
support = {2011/16765-0//Fundação de Amparo à Pesquisa do Estado de São Paulo/ ; 478559/2011-9//Conselho Nacional de Desenvolvimento Científico e Tecnológico (BR)/ ; },
mesh = {Animals ; Ants/*microbiology ; Fungi/*physiology ; Symbiosis/*physiology ; },
abstract = {Chemical compounds are key to understand symbiotic interactions. In the leafcutter ant-microbe symbiosis a plethora of filamentous fungi continuously gain access the ant colonies through plant substrate collected by workers. Many filamentous fungi are considered transient in attine ant colonies, however, their real ecological role in this environment still remains unclear. A possible role of these microorganisms is the antagonism towards Leucoagaricus gongylophorus, the mutualistic fungus that serve as food for several leafcutter ant species. Here, we showed the antagonism of filamentous fungi isolated from different sources, and the negative impacts of their metabolites on the growth of the ant-fungal cultivar. Our results demonstrate that the chemical compounds produced by filamentous fungi can harm the mutualistic fungus of leafcutter ants.},
}
@article {pmid30203242,
year = {2018},
author = {Su, Y and Zhou, Z and Yu, X},
title = {Possible roles of glutamine synthetase in responding to environmental changes in a scleractinian coral.},
journal = {Molecular biology reports},
volume = {},
number = {},
pages = {},
doi = {10.1007/s11033-018-4369-3},
pmid = {30203242},
issn = {1573-4978},
support = {31772460//National Natural Science Foundation of China/ ; 20164158//Natural Science Foundation of Hainan Province/ ; kyqd1554//scientific research foundation of Hainan University/ ; },
abstract = {Glutamine synthetase is an enzyme that plays an essential role in the metabolism of nitrogen by catalyzing the condensation of glutamate and ammonia to form glutamine. In this study, the activity and responses of glutamine synthetase towards environmental changes were investigated in the scleractinian coral Pocillopora damicornis. The identified glutamine synthetase (PdGS) was comprised of 362 amino acids and predicted to contain one Gln-synt_N and one Gln-synt_C domain. Expression of PdGS mRNA increased significantly after 12 h (1.28-fold, p < 0.05) of exposure to elevated ammonium, while glutamine synthetase activity increased significantly from 12 to 24 h, peaking at 12 h (54.80 U mg-1, p < 0.05). The recombinant protein of the mature PdGS (rPdGS) was expressed in E. coli BL21, and its activities were detected under different temperature, pH and glufosinate levels. The highest levels of rPdGS activity were observed at 25 °C and pH 8 respectively, but decreased significantly at lower temperature, and higher or lower pH. Furthermore, the level of rPdGS activities was negatively correlated with the concentration of glufosinate, specifically decreasing at 10-5 mol L-1 glufosinate to be less than 50% (p < 0.05) of that in the blank. These results collectively suggest that PdGS, as a homologue of glutamine synthetase, was involved in the nitrogen assimilation in the scleractinian coral. Further, its physiological functions could be suppressed by high temperature, ocean acidification and residual glufosinate, which might further regulate the coral-zooxanthella symbiosis via the nitrogen metabolism in the scleractinian coral P. damicornis.},
}
@article {pmid30201781,
year = {2018},
author = {Compton, KK and Hildreth, SB and Helm, RF and Scharf, BE},
title = {Sinorhizobium meliloti Chemoreceptor McpV Senses Short-Chain Carboxylates via Direct Binding.},
journal = {Journal of bacteriology},
volume = {200},
number = {23},
pages = {},
doi = {10.1128/JB.00519-18},
pmid = {30201781},
issn = {1098-5530},
abstract = {Sinorhizobium meliloti is a soil-dwelling endosymbiont of alfalfa that has eight chemoreceptors to sense environmental stimuli during its free-living state. The functions of two receptors have been characterized, with McpU and McpX serving as general amino acid and quaternary ammonium compound sensors, respectively. Both receptors use a dual Cache (calcium channels and chemotaxis receptors) domain for ligand binding. We identified that the ligand-binding periplasmic region (PR) of McpV contains a single Cache domain. Homology modeling revealed that McpVPR is structurally similar to a sensor domain of a chemoreceptor with unknown function from Anaeromyxobacter dehalogenans, which crystallized with acetate in its binding pocket. We therefore assayed McpV for carboxylate binding and S. meliloti for carboxylate sensing. Differential scanning fluorimetry identified 10 potential ligands for McpVPR Nine of these are monocarboxylates with chain lengths between two and four carbons. We selected seven compounds for capillary assay analysis, which established positive chemotaxis of the S. meliloti wild type, with concentrations of peak attraction at 1 mM for acetate, propionate, pyruvate, and glycolate, and at 100 mM for formate and acetoacetate. Deletion of mcpV or mutation of residues essential for ligand coordination abolished positive chemotaxis to carboxylates. Using microcalorimetry, we determined that dissociation constants of the seven ligands with McpVPR were in the micromolar range. An McpVPR variant with a mutation in the ligand coordination site displayed no binding to isobutyrate or propionate. Of all the carboxylates tested as attractants, only glycolate was detected in alfalfa seed exudates. This work examines the relevance of carboxylates and their sensor to the rhizobium-legume interaction.IMPORTANCE Legumes share a unique association with certain soil-dwelling bacteria known broadly as rhizobia. Through concerted interorganismal communication, a legume allows intracellular infection by its cognate rhizobial species. The plant then forms an organ, the root nodule, dedicated to housing and supplying fixed carbon and nutrients to the bacteria. In return, the engulfed rhizobia, differentiated into bacteroids, fix atmospheric N2 into ammonium for the plant host. This interplay is of great benefit to the cultivation of legumes, such as alfalfa and soybeans, and is initiated by chemotaxis to the host plant. This study on carboxylate chemotaxis contributes to the understanding of rhizobial survival and competition in the rhizosphere and aids the development of commercial inoculants.},
}
@article {pmid30199649,
year = {2018},
author = {Yang, X and Hu, Q and Han, Z and Ruan, X and Jiang, S and Chai, J and Zheng, R},
title = {Effects of exogenous microbial inoculum on the structure and dynamics of bacterial communities in swine carcass composting.},
journal = {Canadian journal of microbiology},
volume = {64},
number = {12},
pages = {1042-1053},
doi = {10.1139/cjm-2018-0303},
pmid = {30199649},
issn = {1480-3275},
abstract = {Composting is a widely accepted method for the disposal of deceased livestock. It is a biological self-heating process during which animal carcasses are converted to fertilizer products. Additional inoculants can facilitate the composting progress. This study investigated how the addition of microbial inoculants could improve the composting effectiveness and could change the structure and dynamics of bacterial communities in the carcass composting process. Four strains of Bacillus were inoculated into the swine carcass composting piles. The groups with the additional inoculants showed a higher temperature in the thermophilic phase and higher germination indices in the composted products. The sequencing results showed that the dominant phyla were Proteobacteria, Firmicutes, and Actinobacteria, and the dominant classified genera were Brevibacterium and Bacillus. Canonical correlation analysis showed that temperature and moisture exerted a stronger influence on the bacterial community diversity. The interaction network of dominant genera and the abundance variation of the bacterial community demonstrated that the inoculated bacterial agent changed the structure of bacterial communities and enriched the diversity of the species due to antagonism and symbiosis among the dominant bacterial communities.},
}
@article {pmid30198143,
year = {2018},
author = {Bachman, BA and Kraus, R and Peterson, CT and Grubbs, RD and Peters, EC},
title = {Growth and reproduction of Echeneis naucrates from the eastern Gulf of Mexico.},
journal = {Journal of fish biology},
volume = {93},
number = {4},
pages = {755-758},
doi = {10.1111/jfb.13790},
pmid = {30198143},
issn = {1095-8649},
support = {//Guy Harvey Oceans Foundation/ ; //NOAA GulfSPAN Program/ ; },
abstract = {This study describes growth and reproductive characteristics of a facultative elasmobranch symbiont, Echeneis naucrates. Females grew slower but achieved a larger size than males (growth coefficient, K = 0.25 and 0.38 year-1 , and mean maximum size, L∞ = 603 and 477 mm, respectively). Mean relative batch fecundity was 39.5 (s.d. = 13.1). Gonadosomatic indices peaked in July and August for males and females, respectively, with histology evidence of readiness to spawn or active spawning in August. Host-symbiont length ratios increased linearly with sharksucker length (y = 0.0402 + 0.0003x, adjusted R2 = 0.56).},
}
@article {pmid30197700,
year = {2018},
author = {Igiehon, NO and Babalola, OO},
title = {Below-ground-above-ground Plant-microbial Interactions: Focusing on Soybean, Rhizobacteria and Mycorrhizal Fungi.},
journal = {The open microbiology journal},
volume = {12},
number = {},
pages = {261-279},
doi = {10.2174/1874285801812010261},
pmid = {30197700},
issn = {1874-2858},
abstract = {Introduction: Organisms seldom exist in isolation and are usually involved in interactions with several hosts and these interactions in conjunction with the physicochemical parameters of the soil affect plant growth and development. Researches into below and aboveground microbial community are unveiling a myriad of intriguing interactions within the rhizosphere, and many of the interactions are facilitated by exudates that are secreted by plants roots. These interactions can be harnessed for beneficial use in agriculture to enhance crop productivity especially in semi-arid and arid environments.<br><br>The Rhizosphere: The rhizosphere is the region of soil close to plants roots that contain large number of diverse organisms. Examples of microbial candidates that are found in the rhizosphere include the Arbuscular Mycorrhizal Fungi (AMF) and rhizobacteria. These rhizosphere microorganisms use plant root secretions such as mucilage and flavonoids which are able to influence their diversity and function and also enhance their potential to colonize plants root.<br><br>In the natural environments, plants live in interactions with different microorganisms, which thrive belowground in the rhizosphere and aboveground in the phyllosphere. Some of the plant-microbial interactions (which can be in the form of antagonism, amensalism, parasitism and symbiosis) protect the host plants against detrimental microbial and non-microbial invaders and provide nutrients for plants while others negatively affect plants. These interactions can influence below-ground-above-ground plants' biomass development thereby playing significant role in sustaining plants. Therefore, understanding microbial interactions within the rhizosphere and phyllosphere is urgent towards farming practices that are less dependent on conventional chemical fertilizers, which have known negative impacts on the environments.<br><br>Drought stress is one of the major factors militating against agricultural productivity globally and is likely to further increase. Belowground rhizobacteria interactions could play important role in alleviating drought stress in plants. These beneficial rhizobacterial colonize the rhizosphere of plants and impart drought tolerance by up regulation or down regulation of drought responsive genes such as ascorbate peroxidase, S-adenosyl-methionine synthetase, and heat shock protein.<br><br>Investigating complex microbial community in the environment is a big challenge. Therefore, omic studies of microorganisms that inhabit the rhizosphere are important since this is where most plant-microbial interactions occur. One of the aims of this review is not to give detailed account of all the present omic techniques, but instead to highlight the current omic techniques that can possibly lead to detection of novel genes and their respective proteins within the rhizosphere which may be of significance in enhancing crop plants (such as soybean) productivity especially in semi-arid and arid environments.<br><br>Plant-microbial interactions are not totally understood, and there is, therefore, the need for further studies on these interactions in order to get more insights that may be useful in sustainable agricultural development. With the emergence of omic techniques, it is now possible to effectively monitor transformations in rhizosphere microbial community together with their effects on plant development. This may pave way for scientists to discover new microbial species that will interact effectively with plants. Such microbial species can be used as biofertilizers and/or bio-pesticides to increase crop yield and enhance global food security.},
}
@article {pmid30197267,
year = {2019},
author = {Al-Khafaji, AM and Clegg, SR and Pinder, AC and Luu, L and Hansford, KM and Seelig, F and Dinnis, RE and Margos, G and Medlock, JM and Feil, EJ and Darby, AC and McGarry, JW and Gilbert, L and Plantard, O and Sassera, D and Makepeace, BL},
title = {Multi-locus sequence typing of Ixodes ricinus and its symbiont Candidatus Midichloria mitochondrii across Europe reveals evidence of local co-cladogenesis in Scotland.},
journal = {Ticks and tick-borne diseases},
volume = {10},
number = {1},
pages = {52-62},
doi = {10.1016/j.ttbdis.2018.08.016},
pmid = {30197267},
issn = {1877-9603},
abstract = {Ticks have relatively complex microbiomes, but only a small proportion of the bacterial symbionts recorded from ticks are vertically transmitted. Moreover, co-cladogenesis between ticks and their symbionts, indicating an intimate relationship over evolutionary history driven by a mutualistic association, is the exception rather than the rule. One of the most widespread tick symbionts is Candidatus Midichloria, which has been detected in all of the major tick genera of medical and veterinary importance. In some species of Ixodes, such as the sheep tick Ixodes ricinus (infected with Candidatus Midichloria mitochondrii), the symbiont is fixed in wild adult female ticks, suggesting an obligate mutualism. However, almost no information is available on genetic variation in Candidatus M. mitochondrii or possible co-cladogenesis with its host across its geographic range. Here, we report the first survey of Candidatus M. mitochondrii in I. ricinus in Great Britain and a multi-locus sequence typing (MLST) analysis of tick and symbiont between British ticks and those collected in continental Europe. We show that while the prevalence of the symbiont in nymphs collected in England is similar to that reported from the continent, a higher prevalence in nymphs and adult males is apparent in Wales. In general, Candidatus M. mitochondrii exhibits very low levels of sequence diversity, although a consistent signal of host-symbiont coevolution was apparent in Scotland. Moreover, the tick MLST scheme revealed that Scottish specimens form a clade that is partially separated from other British ticks, with almost no contribution of continental sequence types in this north-westerly border of the tick's natural range. The low diversity of Candidatus M. mitochondrii, in contrast with previously reported high rates of polymorphism in I. ricinus mitogenomes, suggests that the symbiont may have swept across Europe recently via a horizontal, rather than vertical, transmission route.},
}
@article {pmid30195323,
year = {2018},
author = {Matiiv, AB and Chekunova, EM},
title = {Aureochromes - Blue Light Receptors.},
journal = {Biochemistry. Biokhimiia},
volume = {83},
number = {6},
pages = {662-673},
doi = {10.1134/S0006297918060044},
pmid = {30195323},
issn = {1608-3040},
mesh = {Fungi/metabolism ; Light ; Optogenetics ; Photoreceptors, Microbial/chemistry/classification/*metabolism ; Photoreceptors, Plant/chemistry/classification/*metabolism ; Photosynthesis ; Plants/metabolism ; Signal Transduction ; },
abstract = {A variety of living organisms including bacteria, fungi, animals, and plants use blue light (BL) to adapt to changing ambient light. Photosynthetic forms (plants and algae) require energy of light for photosynthesis, movements, development, and regulation of activity. Several complex light-sensitive systems evolved in eukaryotic cells to use the information of light efficiently with photoreceptors selectively absorbing various segments of the solar spectrum, being the first components in the light signal transduction chain. They are most diverse in algae. Photosynthetic stramenopiles, which received chloroplasts from red algae during secondary symbiosis, play an important role in ecosystems and aquaculture, being primary producers. These taxa acquired the ability to use BL for regulation of such processes as phototropism, chloroplast photo-relocation movement, and photomorphogenesis. A new type of BL receptor - aureochrome (AUREO) - was identified in Vaucheria frigida in 2007. AUREO consists of two domains: bZIP (basic-region leucine zipper) domain and LOV (light-oxygen-voltage-sensing) domain, and thus this photoreceptor is a BL-sensitive transcription factor. This review presents current data on the structure, mechanisms of action, and biochemical features of aureochromes.},
}
@article {pmid30192637,
year = {2018},
author = {Ausubel, FM},
title = {Tracing My Roots: How I Became a Plant Biologist.},
journal = {Annual review of genetics},
volume = {52},
number = {},
pages = {1-20},
doi = {10.1146/annurev-genet-120417-031722},
pmid = {30192637},
issn = {1545-2948},
abstract = {My trajectory to becoming a plant biologist was shaped by a complex mix of scientific, political, sociological, and personal factors. I was trained as a microbiologist and molecular biologist in the late 1960s and early 1970s, a time of political upheaval surrounding the Vietnam War. My political activism taught me to be wary of the potential misuses of scientific knowledge and to promote the positive applications of science for the benefit of society. I chose agricultural science for my postdoctoral work. Because I was not trained as a plant biologist, I devised a postdoctoral project that took advantage of my microbiological training, and I explored using genetic technologies to transfer the ability to fix nitrogen from prokaryotic nitrogen-fixing species to the model plant Arabidopsis thaliana with the ultimate goal of engineering crop plants. The invention of recombinant DNA technology greatly facilitated the cloning and manipulation of bacterial nitrogen-fixation (nif) genes, but it also forced me to consider how much genetic engineering of organisms, including human beings, is acceptable. My laboratory has additionally studied host-pathogen interactions using Arabidopsis and the nematode Caenorhabditis elegans as model hosts.},
}
@article {pmid30192418,
year = {2018},
author = {Ratib, NR and Sabio, EY and Mendoza, C and Barnett, MJ and Clover, SB and Ortega, JA and Dela Cruz, FM and Balderas, D and White, H and Long, SR and Chen, EJ},
title = {Genome-wide identification of genes directly regulated by ChvI and a consensus sequence for ChvI binding in Sinorhizobium meliloti.},
journal = {Molecular microbiology},
volume = {110},
number = {4},
pages = {596-615},
doi = {10.1111/mmi.14119},
pmid = {30192418},
issn = {1365-2958},
support = {//California State University Special Fund for Research, Scholarship, and Creative Activity Award/ ; 5T34GM008612-20//National Institute of General Medical Sciences/ ; 5T34GM008612-23//National Institute of General Medical Sciences/ ; R01 GM093628//National Institute of General Medical Sciences/ ; IOS-0818981//Division of Integrative Organismal Systems/ ; //Fullerton/ ; //California State University/ ; },
abstract = {ExoS/ChvI two-component signaling in the nitrogen-fixing α-proteobacterium Sinorhizobium meliloti is required for symbiosis and regulates exopolysaccharide production, motility, cell envelope integrity and nutrient utilization in free-living bacteria. However, identification of many ExoS/ChvI direct transcriptional target genes has remained elusive. Here, we performed chromatin immunoprecipitation followed by microarray analysis (chIP-chip) to globally identify DNA regions bound by ChvI protein in S. meliloti. We then performed qRT-PCR with chvI mutant strains to test ChvI-dependent expression of genes downstream of the ChvI-bound DNA regions. We identified 64 direct target genes of ChvI, including exoY, rem and chvI itself. We also identified ChvI direct target candidates, like exoR, that are likely controlled by additional regulators. Analysis of upstream sequences from the 64 ChvI direct target genes identified a 15 bp-long consensus sequence. Using electrophoretic mobility shift assays and transcriptional fusions with exoY, SMb21440, SMc00084, SMc01580, chvI, and ropB1, we demonstrated this consensus sequence is important for ChvI binding to DNA and transcription of ChvI direct target genes. Thus, we have comprehensively identified ChvI regulon genes and a 'ChvI box' bound by ChvI. Many ChvI direct target genes may influence the cell envelope, consistent with the critical role of ExoS/ChvI in growth and microbe-host interactions.},
}
@article {pmid30186672,
year = {2018},
author = {Ross, BJ and Hallock, P},
title = {Challenges in using CellTracker Green on foraminifers that host algal endosymbionts.},
journal = {PeerJ},
volume = {6},
number = {},
pages = {e5304},
doi = {10.7717/peerj.5304},
pmid = {30186672},
issn = {2167-8359},
abstract = {The uses of fluorescent microscopy and fluorescent probes, such as the metabolically activated probe CellTracker™ Green CMFDA (CTG), have become common in studies of living Foraminifera. This metabolic requirement, as well as the relatively quick production of the fluorescent reaction products, makes CTG a prime candidate for determining mortality in bioassay and other laboratory experiments. Previous work with the foraminifer Amphistegina gibbosa, which hosts diatom endosymbionts, has shown that the species is capable of surviving both acute chemical exposure and extended periods of total darkness by entering a low-activity dormant state. This paper explores the use of CTG and fluorescent microscopy to determine mortality in such experiments, as well as to explore the physiology of dormant foraminifers. The application of CTG was found to be complicated by the autofluorescence of the diatom symbionts, which masks the signal of the CTG, as well as by interactions between CTG and propylene glycol, a chemical of interest known to cause dormancy. These complications necessitated adapting methods from earlier studies using CTG. Here we present observations on CTG fluorescence and autofluorescence in A. gibbosa following both chemical exposure and periods of total darkness. While CTG can indicate vital activity in dormant foraminifers, complications include underestimates of total survival and recovery, and falsely indicating dead individuals as live due to rapid microbial colonization. Nonetheless, the brightness of the CTG signal in dormant individuals exposed to propylene glycol supports previously published results of survival patterns in A. gibbosa. Observations of CTG fluorescence in individuals kept for extended periods in aphotic conditions indicate uptake of CTG may begin within 30 min of exposure to light, suggesting darkness-induced dormancy and subsequent recovery can occur on short time scales. These results suggest that CTG accurately reflects changes associated with dormancy, and can be useful in laboratory experiments utilizing symbiont-bearing foraminifers.},
}
@article {pmid30185979,
year = {2018},
author = {Tena, G},
title = {Slimy symbiosis.},
journal = {Nature plants},
volume = {4},
number = {9},
pages = {629},
doi = {10.1038/s41477-018-0257-z},
pmid = {30185979},
issn = {2055-0278},
}
@article {pmid30184779,
year = {2018},
author = {Giram, PS and Shitole, A and Nande, SS and Sharma, N and Garnaik, B},
title = {Fast dissolving moxifloxacin hydrochloride antibiotic drug from electrospun Eudragit L-100 nonwoven nanofibrous Mats.},
journal = {Materials science &amp; engineering. C, Materials for biological applications},
volume = {92},
number = {},
pages = {526-539},
doi = {10.1016/j.msec.2018.06.031},
pmid = {30184779},
issn = {1873-0191},
abstract = {Antimicrobial electrospun nonwoven Eudragit L-100 nanofibrous mats containing Moxifloxacin hydrochloride (MOX-HCL) were fabricated for fast dissolving drug delivery systems (DDSs) associated with wound infection. The morphological characterization of nanofibers using ESEM revealed that the average diameter of non-woven nanofibrous mats ranges 200-600 nm. The nanofiber showed cylindrical shape with crack on the surface. Differential scanning calorimetric (DSC) and Wide Angle X-ray diffraction (WAXRD) demonstrate that the drug exists in an amorphous state in the nanofibers. Nanofibrous mats were also tested for mechanical strength, contact angle, swelling assay, haemolysis and disintegration test. In vitro disintegration tests demonstrated that the dissolution of Eudragit L-100 fiber mats was within 25 s which was higher compared to the pure drug. The Eudragit nanofibers showed pH-dependent drug release profiles, with slow release at pH 1.2 and burst release (around 30 s) at pH 6.8. The in-vitro quantitative and qualitative antimicrobial assay showed that the developed Eudragit L-100 nanofibrous mats with MOX-HCL concentration of 1%, 5% and 15 wt% exhibited antibacterial activities against both gram positive (Staphylococcus aureus) and gram negative (Escherichia coli) bacteria. The in-vitro cytotoxicity assay using mouse fibroblast NIH/3T3 cells demonstrated significant biocompatibility of nanofiber mats. As per the results of biological evaluation, Eudragit L-100 nanofibrous mats with 1wt% MOX-HCL could be a suitable substrate for biomedical applications. Eudragit L-100 nanofibrous mats containing Moxifloxacin hydrochloride (MOX-HCL) showed immediate DDSs for localized drug release in the wound infection at slightly acidic or alkaline conditions where faster drug release rate is required for wound healing.},
}
@article {pmid30177961,
year = {2018},
author = {Tiwari, R and Negandhi, H and Zodpey, SP},
title = {Health Management Workforce for India in 2030.},
journal = {Frontiers in public health},
volume = {6},
number = {},
pages = {227},
doi = {10.3389/fpubh.2018.00227},
pmid = {30177961},
issn = {2296-2565},
abstract = {Introduction: Since its launch in the year 2005, National Rural Health Mission (NHM) has exhibited a felt need for health management training in India against the background of a shortfall of trained public health managers in the country. In India's context, health (hospital) management professionals are those, who are working in the health sector, belonging to medical and non-medical backgrounds and are trained in health (hospital) management/administration programs or other public health programs (for e.g., Master of Public Health) wherein health (hospital) management/administration is significant part of the curriculum. The presence of trained management professionals in the health sector has grown over the years. Objectives: To estimate the supply, need and requirement for health management professionals for India in the year 2030. Materials and methods: The supply data for health management professionals was calculated based on the output from various academic programs related to health management/administration and other public health programs. Need was calculated using &quot;service target approach&quot; and benchmark analysis with 2.97 health managers per 100,000 population (NACCHO 2011). Supply-need gap was estimated using normative need as base number for projections whereas for rest of the years (2018-2030) projections were done at a constant growth rate as per India's population projections. Results: The overall supply capacity of trained health management professionals was 3,463 for 2017. However, based upon a service target approach India requires 11,304 health management professionals in 2017. If India is to reach the normative standards of 2.97 health managers per 100,000 population, the country would need 39,774 health management professionals in 2017. This need would increase to approximately 44,936 health management professionals by the year 2030 to maintain the normative standard of 2.97 health managers per 100,000 population. Conclusions: The supply side will match the requirement of HMPs earliest by the year 2026 in a high seat occupancy scenario.Moreover, there is a need to improve the quality of the output in terms of an explicitly stated and standardized competency framework that is tailored to the Indian context.},
}
@article {pmid30177945,
year = {2018},
author = {Kelly, S and Mun, T and Stougaard, J and Ben, C and Andersen, SU},
title = {Distinct Lotus japonicus Transcriptomic Responses to a Spectrum of Bacteria Ranging From Symbiotic to Pathogenic.},
journal = {Frontiers in plant science},
volume = {9},
number = {},
pages = {1218},
doi = {10.3389/fpls.2018.01218},
pmid = {30177945},
issn = {1664-462X},
abstract = {Lotus japonicus is a well-studied nodulating legume and a model organism for the investigation of plant-microbe interactions. The majority of legume transcriptome studies have focused on interactions with compatible symbionts, whereas responses to non-adapted rhizobia and pathogenic bacteria have not been well-characterized. In this study, we first characterized the transcriptomic response of L. japonicus to its compatible symbiont, Mesorhizobium loti R7A, through RNA-seq analysis of various plant tissues. Early symbiotic signaling was largely Nod factor-dependent and enhanced within root hairs, and we observed large-scale transcriptional reprogramming in nodule primordia and mature nitrogen-fixing nodules. We then characterized root transcriptional responses to a spectrum of L. japonicus interacting bacteria ranging from semi-compatible symbionts to pathogens. M. loti R7A and the semi-compatible strain Sinorhizobium fredii HH103 showed remarkably similar responses, allowing us to identify a small number of genes potentially involved in differentiating between fully and semi-compatible symbionts. The incompatible symbiont Bradyrhizobium elkanii USDA61 induced a more attenuated response, but the weakest response was observed for the foliar pathogen Pseudomonas syringae pv. tomato DC3000, where the affected genes also responded to other tested bacteria, pointing to a small set of common bacterial response genes. In contrast, the root pathogen Ralstonia solanacearum JS763 induced a pronounced and distinct transcriptomic pathogen response, which we compared to the results of the other treatments. This comparative analysis did not support the concept that an early defense-like response is generally evoked by compatible rhizobia during establishment of symbiosis.},
}
@article {pmid30176432,
year = {2018},
author = {Váczi, P and Gauslaa, Y and Solhaug, KA},
title = {Efficient fungal UV-screening provides a remarkably high UV-B tolerance of photosystem II in lichen photobionts.},
journal = {Plant physiology and biochemistry : PPB},
volume = {132},
number = {},
pages = {89-94},
doi = {10.1016/j.plaphy.2018.08.033},
pmid = {30176432},
issn = {1873-2690},
mesh = {Adaptation, Physiological/*radiation effects ; Fluorometry ; Lichens/*microbiology/*physiology/radiation effects ; Photosystem II Protein Complex/*metabolism ; Symbiosis ; *Ultraviolet Rays ; },
abstract = {Lichen photobionts in situ have an extremely UV-B tolerant photosystem II efficiency (Fv/Fm). We have quantified the UV-B-screening offered by the mycobiont and the photobiont separately. The foliose lichens Nephroma arcticum and Umbilicaria spodochroa with 1: intact or 2: removed cortices were exposed to 0.7 Wm-2 UV-BBE for 4 h. Intact thalli experienced no reduction in Fv/Fm, whereas cortex removal lowered Fv/Fm in exposed photobiont layers by 22% for U. spodochroa and by 14% for N. arcticum. We also gave this UV-B dose to algal cultures of Coccomyxa and Trebouxia, the photobiont genera of N. arcticum and U. spodochroa, respectively. UV-B caused a 56% reduction in Fv/Fm for Coccomyxa, and as much as 98% in Trebouxia. The fluorescence excitation ratio (FER) technique comparing the fluorescence from UV-B or UV-A-excitation light with blue green excitation light using a Xe-PAM fluorometer showed that these photobiont genera did not screen any UV-B or UV-A The FER technique with a Multiplex fluorometer estimated the UV-A screening of isolated algae to be 13-16%, whereas intact lichens screened 92-95% of the UV-A. In conclusion, the cortex of N. arcticum and U. spodochroa transmitted no UV-B and little UV-A to the photobiont layer beneath. Thereby, the upper lichen cortex forms an efficient fungal solar radiation screen providing a high UV-B tolerance for studied photobionts in situ. By contrast, isolated photobionts have no UV-B screening and thus depend on their fungal partners in nature.},
}
@article {pmid30175608,
year = {2018},
author = {Hagymási, K and Bacsárdi, A and Egresi, A and Berta, E and Tulassay, Z and Lengyel, G},
title = {[The role of gut microbiota in chronic liver diseases, and treatment possibilities].},
journal = {Orvosi hetilap},
volume = {159},
number = {36},
pages = {1465-1474},
doi = {10.1556/650.2018.31178},
pmid = {30175608},
issn = {0030-6002},
mesh = {Gastrointestinal Microbiome/*physiology ; Gastrointestinal Tract/*microbiology ; Humans ; Intestines/microbiology ; Liver/*microbiology ; Liver Cirrhosis/microbiology ; Liver Diseases/microbiology/*physiopathology ; Non-alcoholic Fatty Liver Disease/microbiology ; Probiotics/*metabolism ; },
abstract = {The community of microorganisms in the intestine, namely gut microbiome lives in symbiosis with the host, contributing to its homeostasis and influencing it simultaneously. It can be suspected that gut microbiome plays a central role in the pathophysiology of intestinal and extraintestinal diseases: determining their development, progress and complications. Recently, intestinal microbiome has become a highlighted field of interest and important topic in research, especially in hepatology. It is in the focus of relevant research as the liver is the organ which meets nutrients, bacterial components, toxins and metabolites at first, as a filter. The evolvement of different liver diseases - just like alcoholic and non-alcoholic fatty liver disease, steatohepatitis, cirrhosis or hepatocellular carcinoma - correlates with the changed composition and activity of gut microbiome. Thus, it can be hypothesized that pre-, pro- and antibiotics could have an impact on the treatment of these diseases. In our review article, the relationship between intestinal flora and liver diseases with different etiologies as well as therapeutic possibilities are discussed. Orv Hetil. 2018; 159(36): 1465-1474.},
}
@article {pmid30172125,
year = {2018},
author = {Tang, J and Ni, X and Zhou, Z and Wang, L and Lin, S},
title = {Acute microplastic exposure raises stress response and suppresses detoxification and immune capacities in the scleractinian coral Pocillopora damicornis.},
journal = {Environmental pollution (Barking, Essex : 1987)},
volume = {243},
number = {Pt A},
pages = {66-74},
doi = {10.1016/j.envpol.2018.08.045},
pmid = {30172125},
issn = {1873-6424},
abstract = {Microplastics are widespread emerging contaminants that have been found globally in the marine and freshwater ecosystem, but there is limited knowledge regarding its impact on coral reef ecosystem and underpinning mechanism. In the present study, using Pocillopora damicornis as a model, we investigated cytological, physiological, and molecular responses of a scleractinian coral to acute microplastic exposure. No significant changes were observed in the density of symbiotic zooxanthellae during the entire period of microplastic exposure, while its chlorophyll content increased significantly at 12 h of microplastic exposure. We observed significant increases in the activities of antioxidant enzymes such as superoxide dismutase and catalase, significant decrease in the detoxifying enzyme glutathione S-transferase and the immune enzyme alkaline phosphatase, but no change in the other immune enzyme phenoloxidase during the whole experiment period. Transcriptomic analysis revealed 134 significantly up-regulated coral genes at 12 h after the exposure, enriched in 11 GO terms mostly related to stress response, zymogen granule, and JNK signal pathway. Meanwhile, 215 coral genes were significantly down-regulated at 12 h after exposure, enriched in 25 GO terms involved in sterol transport and EGF-ERK1/2 signal pathway. In contrast, only 12 zooxanthella genes exhibited significant up-regulation and 95 genes down-regulation at 12 h after the microplastic exposure; genes regulating synthesis and export of glucose and amino acids were not impacted. These results suggest that acute exposure of microplastics can activate the stress response of the scleractinian coral P. damicornis, and repress its detoxification and immune system through the JNK and ERK signal pathways. These demonstrate that microplastic exposure can compromise the anti-stress capacity and immune system of the scleractinian coral P. damicornis, despite the minimal impact on the abundance and major photosynthate translocation transporters of the symbiont in the short term.},
}
@article {pmid30168644,
year = {2018},
author = {Yao, S and Lyu, S and An, Y and Lu, J and Gjermansen, C and Schramm, A},
title = {Microalgae-bacteria symbiosis in microalgal growth and biofuel production: a review.},
journal = {Journal of applied microbiology},
volume = {},
number = {},
pages = {},
doi = {10.1111/jam.14095},
pmid = {30168644},
issn = {1365-2672},
support = {//Shenyang Agricultural University Talent Program/ ; },
abstract = {Photosynthetic microalgae can capture solar energy and convert it to bioenergy and biochemical products. In nature or industrial processes, microalgae live together with bacterial communities and may maintain symbiotic relationships. In general interactions, microalgae exude dissolved organic carbon that becomes available to bacteria. In return, the bacteria remineralize sulphur, nitrogen and phosphorous to support the further growth of microalgae. In specific interactions, heterotrophic bacteria supply B vitamins as organic cofactors or produce siderophores to bind iron, which could be utilized by microalgae, while the algae supply fixed carbon to the bacteria in return. In this review, we focus on mutualistic relationship between microalgae and bacteria, summarizing recent studies on the mechanisms involved in microalgae-bacteria symbiosis. Symbiotic bacteria on promoting microalgal growth are described and the relevance of microalgae-bacteria interactions for biofuel production processes is discussed. Symbiotic microalgae-bacteria consortia could be utilized to improve microalgal biomass production and to enrich the biomass with valuable chemical and energy compounds. The suitable control of such biological interactions between microalgae and bacteria will help to improve the microalgae-based biomass and biofuel production in the future.},
}
@article {pmid30166437,
year = {2018},
author = {Tsikou, D and Yan, Z and Holt, DB and Abel, NB and Reid, DE and Madsen, LH and Bhasin, H and Sexauer, M and Stougaard, J and Markmann, K},
title = {Systemic control of legume susceptibility to rhizobial infection by a mobile microRNA.},
journal = {Science (New York, N.Y.)},
volume = {362},
number = {6411},
pages = {233-236},
doi = {10.1126/science.aat6907},
pmid = {30166437},
issn = {1095-9203},
abstract = {Nitrogen-fixing root nodules on legumes result from two developmental processes, bacterial infection and nodule organogenesis. To balance symbiosis and plant growth, legume hosts restrict nodule numbers through an inducible autoregulatory process. Here, we present a mechanism where repression of a negative regulator ensures symbiotic susceptibility of uninfected roots of the host Lotus japonicus We show that microRNA miR2111 undergoes shoot-to-root translocation to control rhizobial infection through posttranscriptional regulation of the symbiosis suppressor TOO MUCH LOVE in roots. miR2111 maintains a susceptible default status in uninfected hosts and functions as an activator of symbiosis downstream of LOTUS HISTIDINE KINASE1-mediated cytokinin perception in roots and HYPERNODULATION ABERRANT ROOT FORMATION1, a shoot factor in autoregulation. The miR2111-TML node ensures activation of feedback regulation to balance infection and nodulation events.},
}
@article {pmid30165827,
year = {2018},
author = {Aguilar, A and Mora, Y and Dávalos, A and Girard, L and Mora, J and Peralta, H},
title = {Analysis of genome sequence and symbiotic ability of rhizobial strains isolated from seeds of common bean (Phaseolus vulgaris).},
journal = {BMC genomics},
volume = {19},
number = {1},
pages = {645},
doi = {10.1186/s12864-018-5023-0},
pmid = {30165827},
issn = {1471-2164},
support = {IN208216//Dirección General de Asuntos del Personal Académico, Universidad Nacional Autónoma de México/ ; 213606//Consejo Nacional de Ciencia y Tecnología/ ; },
abstract = {BACKGROUND: Rhizobia are alpha-proteobacteria commonly found in soil and root nodules of legumes. It was recently reported that nitrogen-fixing rhizobia also inhabit legume seeds. In this study, we examined whole-genome sequences of seven strains of rhizobia isolated from seeds of common bean (Phaseolus vulgaris).<br><br>RESULTS: Rhizobial strains included in this study belonged to three different species, including Rhizobium phaseoli, R. leguminosarum, and R. grahamii. Genome sequence analyses revealed that six of the strains formed three pairs of highly related strains. Both strains comprising a pair shared all but one plasmid. In two out of three pairs, one of the member strains was effective in nodulation and nitrogen fixation, whereas the other was ineffective. The genome of the ineffective strain in each pair lacked several genes responsible for symbiosis, including nod, nif, and fix genes, whereas that of the effective strain harbored the corresponding genes in clusters, suggesting that recombination events provoked gene loss in ineffective strains. Comparisons of genomic sequences between seed strains and nodule strains of the same species showed high conservation of chromosomal sequences and lower conservation of plasmid sequences. Approximately 70% of all genes were shared among the strains of each species. However, paralogs were more abundant in seed strains than in nodule strains. Functional analysis showed that seed strains were particularly enriched in genes involved in the transport and metabolism of amino acids and carbohydrates, biosynthesis of cofactors and in transposons and prophages. Genomes of seed strains harbored several intact prophages, one of which was inserted at exactly the same genomic position in three strains of R. phaseoli and R. leguminosarum. The R. grahamii strain carried a prophage similar to a gene transfer agent (GTA); this represents the first GTA reported for this genus.<br><br>CONCLUSIONS: Seeds represent a niche for bacteria; their access by rhizobia possibly triggered the infection of phages, recombination, loss or gain of plasmids, and loss of symbiosis genes. This process probably represents ongoing evolution that will eventually convert these strains into obligate endophytes.},
}
@article {pmid30157780,
year = {2018},
author = {Yahiaoui, RY and Bootsma, HJ and den Heijer, CDJ and Pluister, GN and John Paget, W and Spreeuwenberg, P and Trzcinski, K and Stobberingh, EE},
title = {Distribution of serotypes and patterns of antimicrobial resistance among commensal Streptococcus pneumoniae in nine European countries.},
journal = {BMC infectious diseases},
volume = {18},
number = {1},
pages = {440},
doi = {10.1186/s12879-018-3341-0},
pmid = {30157780},
issn = {1471-2334},
support = {223083//the European Commission - DG Research within its 7th Framework Program/ ; },
mesh = {Adolescent ; Adult ; Aged ; Aged, 80 and over ; Anti-Bacterial Agents/therapeutic use ; Child ; Child, Preschool ; Drug Resistance, Bacterial/*genetics ; Europe/epidemiology ; Female ; Humans ; Male ; Middle Aged ; Pneumococcal Infections/blood/drug therapy/*epidemiology ; Seroepidemiologic Studies ; *Serogroup ; Streptococcus pneumoniae/classification/*genetics/isolation &amp; purification ; Symbiosis/genetics ; Young Adult ; },
abstract = {BACKGROUND: Streptococcus pneumoniae is a commensal of the human upper respiratory tract and a major cause of morbidity and mortality worldwide. This paper presents the distribution of serotypes and antimicrobial resistance in commensal S. pneumoniae strains cultured from healthy carriers older than four years of age in nine European countries.<br><br>METHODS: Nasal swabs from healthy persons (age between 4 and 107 years old) were obtained by general practitioners from each country from November 2010 to August 2011. Swabs were cultured for S. pneumoniae using a standardized protocol. Antibiotic resistance was determined for isolated S. pneumoniae by broth microdilution. Capsular sequencing typing was used to identify serotypes, followed by serotype-specific PCR assays in case of ambiguous results.<br><br>RESULTS: Thirty-two thousand one hundred sixty-one nasal swabs were collected from which 937 S. pneumoniae were isolated. A large variation in serotype distribution and antimicrobial resistant serotypes across the participating countries was observed. Pneumococcal vaccination was associated with a higher risk of pneumococcal colonization and antimicrobial resistance independently of country and vaccine used, either conjugate vaccine or PPV 23).<br><br>CONCLUSIONS: Serotype 11A was the most common in carriage followed by serotypes 23A and 19A. The serotypes showing the highest resistance to penicillin were 14 followed by 19A. Serotype 15A showed the highest proportion of multidrug resistance.},
}
@article {pmid30157288,
year = {2018},
author = {Allen, JL and McKenzie, SK and Sleith, RS and Alter, SE},
title = {First genome-wide analysis of the endangered, endemic lichen Cetradonia linearis reveals isolation by distance and strong population structure.},
journal = {American journal of botany},
volume = {105},
number = {9},
pages = {1556-1567},
doi = {10.1002/ajb2.1150},
pmid = {30157288},
issn = {1537-2197},
support = {1145511//National Science Foundation (NSF)/ ; },
abstract = {PREMISE OF THE STUDY: Lichenized fungi are evolutionarily diverse and ecologically important, but little is known about the processes that drive their diversification and genetic differentiation. Distributions are often assumed to be wholly shaped by ecological requirements rather than dispersal limitations. Furthermore, although asexual and sexual reproductive structures are observable, the lack of information about recombination rates makes inferences about reproductive strategies difficult. We investigated the population genomics of Cetradonia linearis, a federally endangered lichen in the southern Appalachians of eastern North America, to test the relative contributions of environmental and geographic distance in shaping genetic structure, and to characterize the mating system and genome-wide recombination.<br><br>METHODS: Whole-genome shotgun sequencing was conducted to generate data for 32 individuals of C. linearis. A reference genome was assembled, and reads from all samples were aligned to generate a set of single-nucleotide polymorphisms for further analyses.<br><br>KEY RESULTS: We found evidence for low rates of recombination and for isolation by distance, but not for isolation by environment. The species is putatively unisexual, given that only one mating-type locus was found. Hindcast species distribution models and the distribution of genetic diversity support C. linearis having a larger range during the Last Glacial Maximum in the southern portion of its current extent.<br><br>CONCLUSIONS: Our findings contribute to the understanding of factors that shape genetic diversity in C. linearis and in fungi more broadly. Because all populations are highly genetically differentiated, the extirpation of any population would mean the loss of unique genetic diversity; therefore, our results support the continued conservation of this species.},
}
@article {pmid30154059,
year = {2019},
author = {Cafiso, A and Sassera, D and Romeo, C and Serra, V and Hervet, C and Bandi, C and Plantard, O and Bazzocchi, C},
title = {Midichloria mitochondrii, endosymbiont of Ixodes ricinus: evidence for the transmission to the vertebrate host during the tick blood meal.},
journal = {Ticks and tick-borne diseases},
volume = {10},
number = {1},
pages = {5-12},
doi = {10.1016/j.ttbdis.2018.08.008},
pmid = {30154059},
issn = {1877-9603},
abstract = {Ticks are important vectors of a variety of pathogens affecting humans and other animals, but they also harbor numerous microorganisms whose role is still limitedly investigated. Ixodes ricinus harbors the endosymbiont Midichloria mitochondrii, which is localized in ovaries and in salivary glands. The bacterium is vertically transmitted and is present in 100% of wild adult females, while prevalence values drop after some generations under laboratory conditions. Molecular and serological evidences showed that M. mitochondrii molecules are transmitted to the vertebrate hosts by I. ricinus during the blood meal. Our work was focused on monitoring M. mitochondrii antigens and DNA in a vertebrate model after infestation with I. ricinus for a time-span of four months. Two groups of rabbits were infested with I. ricinus females, respectively from the wild (naturally infected with the symbiont) and laboratory strain (lab; considered devoid of M. mitochondrii after quantitative PCR investigations) and screened using molecular and serological assays at nine time points. M. mitochondrii presence was detected in rabbits infested with wild I. ricinus ticks, but surprisingly also in those infested with lab ticks, albeit at later time points. This result prompted a more sensitive molecular screening of lab ticks, which were found to harbor very low symbiont loads. Our results indicate that transmission of the bacterium occurs even at low bacterial loads, and that antibody response against M. mitochondrii antigens begins within one week post-infestation with wild I. ricinus. Circulating DNA was detected in the blood of rabbits belonging to both groups up to the end of the experiment, suggesting a replication of the symbiont inside the vertebrate host.},
}
@article {pmid30152755,
year = {2018},
author = {Wang, M and Schäfer, M and Li, D and Halitschke, R and Dong, C and McGale, E and Paetz, C and Song, Y and Li, S and Dong, J and Heiling, S and Groten, K and Franken, P and Bitterlich, M and Harrison, MJ and Paszkowski, U and Baldwin, IT},
title = {Blumenols as shoot markers of root symbiosis with arbuscular mycorrhizal fungi.},
journal = {eLife},
volume = {7},
number = {},
pages = {},
doi = {10.7554/eLife.37093},
pmid = {30152755},
issn = {2050-084X},
support = {276033540220041//European Innovation Partnership Agri/International ; 293926//European Research Council/International ; ClockworkGreen (293926)//ERC Advanced Grant/International ; # DESC0012460//U.S. Department of Energy/International ; Open-access funding//Max-Planck-Gesellschaft/International ; Advanced Grant ClockworkGreen (293926)//European Research Council/International ; 276033540220041//European Innovation Partnership Agricultural Productivity and Sustainability/International ; },
abstract = {High-through-put (HTP) screening for functional arbuscular mycorrhizal fungi (AMF)-associations is challenging because roots must be excavated and colonization evaluated by transcript analysis or microscopy. Here we show that specific leaf-metabolites provide broadly applicable accurate proxies of these associations, suitable for HTP-screens. With a combination of untargeted and targeted metabolomics, we show that shoot accumulations of hydroxy- and carboxyblumenol C-glucosides mirror root AMF-colonization in Nicotiana attenuata plants. Genetic/pharmacologic manipulations indicate that these AMF-indicative foliar blumenols are synthesized and transported from roots to shoots. These blumenol-derived foliar markers, found in many di- and monocotyledonous crop and model plants (Solanum lycopersicum, Solanum tuberosum, Hordeum vulgare, Triticum aestivum, Medicago truncatula and Brachypodium distachyon), are not restricted to particular plant-AMF interactions, and are shown to be applicable for field-based QTL mapping of AMF-related genes.},
}
@article {pmid30152051,
year = {2018},
author = {Russo, G and Carotenuto, G and Fiorilli, V and Volpe, V and Chiapello, M and Van Damme, D and Genre, A},
title = {Ectopic activation of cortical cell division during the accommodation of arbuscular mycorrhizal fungi.},
journal = {The New phytologist},
volume = {},
number = {},
pages = {},
doi = {10.1111/nph.15398},
pmid = {30152051},
issn = {1469-8137},
abstract = {Arbuscular mycorrhizas (AMs) between plants and soil fungi are widespread symbioses with a major role in soil nutrient uptake. In this study we investigated the induction of root cortical cell division during AM colonization by combining morphometric and gene expression analyses with promoter activation and protein localization studies of the cell-plate-associated exocytic marker TPLATE. Our results show that TPLATE promoter is activated in colonized cells of the root cortex where we also observed the appearance of cells that are half the size of the surrounding cells. Furthermore, TPLATE-green fluorescent protein recruitment to developing cell plates highlighted ectopic cell division events in the inner root cortex during early AM colonization. Lastly, transcripts of TPLATE, KNOLLE and Cyclinlike 1 (CYC1) are all upregulated in the same context, alongside endocytic markers Adaptor-Related Protein complex 2 alpha 1 subunit (AP2A1) and Clathrin Heavy Chain 2 (CHC2), known to be active during cell plate formation. This pattern of gene expression was recorded in wild-type Medicago truncatula roots, but not in a common symbiotic signalling pathway mutant where fungal colonization is blocked at the epidermal level. Altogether, these results suggest the activation of cell-division-related mechanisms by AM hosts during the accommodation of the symbiotic fungus.},
}
@article {pmid30151965,
year = {2018},
author = {Mason, CJ and Jones, AG and Felton, GW},
title = {Co-option of microbial associates by insects and their impact on plant-folivore interactions.},
journal = {Plant, cell &amp; environment},
volume = {},
number = {},
pages = {},
doi = {10.1111/pce.13430},
pmid = {30151965},
issn = {1365-3040},
support = {2018-67012-27979//National Institute of Food and Agriculture/ ; AFRI 2017- 67013-26596//National Institute of Food and Agriculture/ ; //USDA NIFA Postdoctoral Fellowship/ ; PEN04576//Hatch Project/ ; IOS-1645548//National Science Foundation/ ; AFRI 2017-67013-26596//United States Department of Agriculture/ ; },
abstract = {Plants possess a suite of traits that make them challenging to consume by insect herbivores. Plant tissues are recalcitrant, have low levels of protein, and may be well defended by chemicals. Insects use diverse strategies for overcoming these barriers, including co-opting metabolic activities from microbial associates. In this review, we discuss the co-option of bacteria and fungi in the herbivore gut. We particularly focus upon chewing, folivorous insects (Coleoptera and Lepidoptera) and discuss the impacts of microbial co-option on herbivore performance and plant responses. We suggest that there are two components to microbial co-option: fixed and plastic relationships. Fixed relationships are involved in integral dietary functions and can be performed by microbial enzymes co-opted into the genome or by stably transferred associates. In contrast, the majority of gut symbionts appear to be looser and perform more facultative, context-dependent functions. This more plastic, variable co-option of bacteria likely produces a greater number of insect phenotypes, which interact differently with plant hosts. By altering plant detection of herbivory or mediating insect interactions with plant defensive compounds, microbes can effectively improve herbivore performance in real time within and between generations.},
}
@article {pmid30151160,
year = {2018},
author = {Coryell, RL and Turnham, KE and de Jesus Ayson, EG and Lavilla-Pltogo, C and Alcala, AC and Sotto, F and Gonzales, B and Nishiguchi, MK},
title = {Phylogeographic patterns in the Philippine archipelago influence symbiont diversity in the bobtail squid-Vibrio mutualism.},
journal = {Ecology and evolution},
volume = {8},
number = {15},
pages = {7421-7435},
doi = {10.1002/ece3.4266},
pmid = {30151160},
issn = {2045-7758},
support = {K12 GM088021/GM/NIGMS NIH HHS/United States ; },
abstract = {Marine microbes encounter a myriad of biotic and abiotic factors that can impact fitness by limiting their range and capacity to move between habitats. This is especially true for environmentally transmitted bacteria that cycle between their hosts and the surrounding habitat. As geologic history, biogeography, and other factors such as water temperature, salinity, and physical barriers can inhibit bacterial movement to novel environments, we chose to examine the genetic architecture of Euprymna albatrossae (Mollusca: Cephalopoda) and their Vibrio fischeri symbionts in the Philippine archipelago using a combined phylogeographic approach. Eleven separate sites in the Philippine islands were examined using haplotype estimates that were examined via nested clade analysis to determine the relationship between E. albatrossae and V. fischeri populations and their geographic location. Identical analyses of molecular variance (AMOVA) were used to estimate variation within and between populations for host and symbiont genetic data. Host animals demonstrated a significant amount of variation within island groups, while symbiont variation was found within individual populations. Nested clade phylogenetic analysis revealed that hosts and symbionts may have colonized this area at different times, with a sudden change in habitat. Additionally, host data indicate restricted gene flow, whereas symbionts show range expansion, followed by periodic restriction to genetic flow. These differences between host and symbiont networks indicate that factors &quot;outside the squid&quot; influence distribution of Philippine V. fischeri. Our results shed light on how geography and changing environmental factors can impact marine symbiotic associations at both local and global scales.},
}
@article {pmid30150781,
year = {2018},
author = {Rossi, S and Schubert, N and Brown, D and Soares, MO and Grosso, V and Rangel-Huerta, E and Maldonado, E},
title = {Linking host morphology and symbiont performance in octocorals.},
journal = {Scientific reports},
volume = {8},
number = {1},
pages = {12823},
doi = {10.1038/s41598-018-31262-3},
pmid = {30150781},
issn = {2045-2322},
abstract = {Octocorals represent an important group in reef communities throughout the tropical seas and, like scleractinian corals, they can be found in symbiosis with the dinoflagellate Symbiodinium. However, while there is extensive research on this symbiosis and its benefits in scleractinians, research on octocorals has focused so far mainly on the host without addressing their symbiosis. Here, we characterized and compared the photophysiological features of nine Caribbean octocoral species with different colony morphologies (sea fan, plumes, whips and rods) and related key morphological features with their respective symbiont photobiology. Colony features (branch shape and thickness), as well as micromorphological features (polyp size, density), were found to be significantly correlated with symbiont performance. Sea fans and plumes, with thinner branches and smaller polyps, favor higher metabolic rates, compared to sea rods with thicker branches and larger polyps. Daily integrated photosynthesis to respiration ratios > 1 indicated that the autotrophic contribution to organisms' energy demands was important in all species, but especially in sea whips. This information represents an important step towards a better understanding of octocoral physiology and its relationship to host morphology, and might also explain to some extent species distribution and susceptibility to environmental stress.},
}
@article {pmid30147704,
year = {2018},
author = {Martín-Rodríguez, JÁ and Leija, A and Formey, D and Hernández, G},
title = {The MicroRNA319d/TCP10 Node Regulates the Common Bean - Rhizobia Nitrogen-Fixing Symbiosis.},
journal = {Frontiers in plant science},
volume = {9},
number = {},
pages = {1175},
doi = {10.3389/fpls.2018.01175},
pmid = {30147704},
issn = {1664-462X},
abstract = {Micro-RNAs from legume plants are emerging as relevant regulators of the rhizobia nitrogen-fixing symbiosis. In this work we functionally characterized the role of the node conformed by micro-RNA319 (miR319) - TEOSINTE BRANCHED/CYCLOIDEA/PCF (TCP) transcription factor in the common bean (Phaseolus vulgaris) - Rhizobium tropici symbiosis. The miR319d, one of nine miR319 isoforms from common bean, was highly expressed in root and nodules from inoculated plants as compared to roots from fertilized plants. The miR319d targets TCP10 (Phvul.005G067950), identified by degradome analysis, whose expression showed a negative correlation with miR319d expression. The phenotypic analysis of R. tropici-inoculated composite plants with transgenic roots/nodules overexpressing or silencing the function of miR319d demonstrated the relevant role of the miR319d/TCP10 node in the common bean rhizobia symbiosis. Increased miR319d resulted in reduced root length/width ratio, increased rhizobial infection evidenced by more deformed root hairs and infection threads, and decreased nodule formation and nitrogenase activity per plant. In addition, these plants with lower TCP10 levels showed decreased expression level of the jasmonic acid (JA) biosynthetic gene: LOX2. The transcription of LOX2 by TCPs has been demonstrated for Arabidopsis and in several plants LOX2 level and JA content have been associate with TCP levels. On this basis, we propose that in roots/nodules of inoculated common bean plants TCP10 could be the transcriptional regulator of LOX2 and the miR319d/TCP10 node could affect nodulation through JA signaling. However, given the complexity of nodulation, the participation of other signaling pathways in the phenotypes observed cannot be ruled out.},
}
@article {pmid30147680,
year = {2018},
author = {Bodawatta, KH and Sam, K and Jønsson, KA and Poulsen, M},
title = {Comparative Analyses of the Digestive Tract Microbiota of New Guinean Passerine Birds.},
journal = {Frontiers in microbiology},
volume = {9},
number = {},
pages = {1830},
doi = {10.3389/fmicb.2018.01830},
pmid = {30147680},
issn = {1664-302X},
abstract = {The digestive tract microbiota (DTM) plays a plethora of functions that enable hosts to exploit novel niches. However, our understanding of the DTM of birds, particularly passerines, and the turnover of microbial communities along the digestive tract are limited. To better understand how passerine DTMs are assembled, and how the composition changes along the digestive tract, we investigated the DTM of seven different compartments along the digestive tract of nine New Guinean passerine bird species using Illumina MiSeq sequencing of the V4 region of the 16S rRNA. Overall, passerine DTMs were dominated by the phyla Firmicutes and Proteobacteria. We found bird species-specific DTM assemblages and the DTM of different compartments from the same species tended to cluster together. We also found a notable relationship between gut community similarity and feeding guilds (insectivores vs. omnivores). The dominant bacterial genera tended to differ between insectivores and omnivores, with insectivores mainly having lactic acid bacteria that may contribute to the breakdown of carbohydrates. Omnivorous DTMs were more diverse than insectivores and dominated by the bacterial phyla Proteobacteria and Tenericutes. These bacteria may contribute to nitrogen metabolism, and the diverse omnivorous DTMs may allow for more flexibility with varying food availability as these species have wider feeding niches. In well-sampled omnivorous species, the dominant bacterial genera changed along the digestive tracts, which was less prominent for insectivores. In conclusion, the DTMs of New Guinean passerines seem to be species specific and, at least in part, be shaped by bird diet. The sampling of DTM along the digestive tract improved capturing of a more complete set of members, with implications for our understanding of the interactions between symbiont and gut compartment functions.},
}
@article {pmid30147271,
year = {2018},
author = {Aphale, D and Kulkarni, A},
title = {Modifications and optimization of manual methods for polymerase chain reaction and 16S rRNA gene sequencing quality community DNA extraction from goat rumen digesta.},
journal = {Veterinary world},
volume = {11},
number = {7},
pages = {990-1000},
doi = {10.14202/vetworld.2018.990-1000},
pmid = {30147271},
issn = {0972-8988},
abstract = {Background and Aim: A critical prerequisite for studying rumen microbial community by high throughput molecular biology methods is good quality community DNA. Current methods of extraction use kits designed for samples from the different origin for rumen. This puts stress on the development of a relevant manual method for DNA extraction. The objective of this study was to modify the existing methods of community DNA extraction and thereby systematic comparison of their efficiency based on DNA yield, purity, 16S rRNA gene sequencing, and identification to determine the optimal DNA extraction methods whose DNA products reflect targeted bacterial communities special to rumen.<br><br>Materials and Methods: Enzymatic method, Chemical method, Enzymatic + Chemical method, and Enzymatic + Chemical + Physical method were modified toward evaluation of community DNA extraction from solid, squeezed, and liquid fractions of goat rumen digesta. Each method was assessed critically for nucleic acid yield and its quality. The methods resulting in high nucleic acid yield, optimal purity ratios with intact band on agarose gel electrophoresis were optimized further. Optimized methods were studied using standard polymerase chain reaction (PCR) with universal bacterial primers and 16S rRNA primers of targeted rumen bacteria. Methods denoting the presence of targeted rumen bacteria were assessed further with 16S rRNA gene sequencing and identification studies. It led toward methods efficacy estimation for molecular biology applications. Effect of rumen sample preservation on community DNA extraction was also studied. Their mean standard deviation values were calculated to understand sampling criticality.<br><br>Results: Modified Chemical method (Cetrimonium bromide) and Enzymatic+Chemical+Physical (ECP) method (Lysozyme-Cetrimonium bromide-Sodium Dodecyl Sulfate-freeze-thaw) could extract 835 ng/µl and 161 ng/µl community DNA from 1.5 g solid and 2 ml squeezed rumen digesta with purity ratios of 1.8 (A260nm/A280 nm) and 2.3 (A260nm/A230 nm) respectively. Comparative analysis showed the better efficiency of ECP method and chemical method toward freshly squeezed rumen digesta and solid rumen digesta. However, sample preservation at -80°C for 1.5 months drastically affected the yield and purity ratios of community DNA. New protocol revealed targeted microbial community having Gram-positive as well as Gram-negative bacteria such as Prevotella ruminicola, Streptococcus lutetiensis, Ruminococcus flavefaciens, Fibrobacter succinogenes, and Selenomonas ruminantium.<br><br>Conclusion: To date, this is the first report of modified methods wherein least chemicals and steps lead toward PCR and 16S rRNA gene sequencing quality community DNA extraction from goat rumen digesta. Detection of targeted rumen bacteria in solid and squeezed rumen digesta proves their strongest association with rumen fiber mat. It also marks the presence of distinct microbial communities in solid and squeezed rumen fractions that in turn differs the performance of each different method employed and yield of nucleic acid obtained. It also leaves a possibility of the presence of complex microbial consortia in squeezed rumen digesta whose DNA extraction methods need more attention. Finally, manual protocols of community DNA extraction may vary in different ruminant which suggests undertaking rigorous research in their establishment.},
}
@article {pmid30147222,
year = {2018},
author = {Takagi, H and Kimoto, K and Fujiki, T and Moriya, K},
title = {Effect of nutritional condition on photosymbiotic consortium of cultured Globigerinoides sacculifer (Rhizaria, Foraminifera).},
journal = {Symbiosis (Philadelphia, Pa.)},
volume = {76},
number = {1},
pages = {25-39},
doi = {10.1007/s13199-017-0530-3},
pmid = {30147222},
issn = {0334-5114},
abstract = {Several foraminifers found in warm and low-nutrient ocean surface water have photosynthetic algae as endosymbionts (photosymbiosis). To understand the trophic interactions, we studied Globigerinoides sacculifer, a spinose planktic foraminifer that has a dinoflagellate endosymbiont. We controlled two nutritional factors, feeding and inorganic nutrients in the seawater. The growth of the host and the symbionts and the photophysiological parameters were monitored under four experimental conditions. The results demonstrated that the holobionts primarily relied on phagotrophy for growth. The foraminifers grew considerably, and the chlorophyll a content per foraminifer, which is an indicator of the symbiont population, increased in the fed groups, but not in the unfed groups. The nutrient-rich seawater used for some of the cultures made no difference in either the growth or photophysiology of the holobionts. These observations indicated that the symbionts mainly utilized metabolites from the hosts for photosynthesis rather than inorganic nutrients in the seawater. Additionally, we observed that the symbionts in the starved hosts maintained their photosynthetic capability for at least 12 days, and that the hosts maintained at least some symbionts until gametogenesis was achieved. This suggests that the hosts have to retain the symbionts as an energy source for reproduction. The symbionts may also play an indispensable role in the metabolic activities of the hosts including waste transport or essential compound synthesis. Overall, our results revealed a novel mode of photosymbiosis in planktic foraminifers which contrasts with that found in benthic photosymbiotic foraminifers and corals.},
}
@article {pmid30146159,
year = {2018},
author = {Qi, B and Han, M},
title = {Microbial Siderophore Enterobactin Promotes Mitochondrial Iron Uptake and Development of the Host via Interaction with ATP Synthase.},
journal = {Cell},
volume = {175},
number = {2},
pages = {571-582.e11},
doi = {10.1016/j.cell.2018.07.032},
pmid = {30146159},
issn = {1097-4172},
abstract = {Elucidating the benefits of individual microbiota-derived molecules in host animals is important for understanding the symbiosis between humans and their microbiota. The bacteria-secreted enterobactin (Ent) is an iron scavenging siderophore with presumed negative effects on hosts. However, the high prevalence of Ent-producing commensal bacteria in the human gut raises the intriguing question regarding a potential host mechanism to beneficially use Ent. We discovered an unexpected and striking role of Ent in supporting growth and the labile iron pool in C. elegans. We show that Ent promotes mitochondrial iron uptake and does so, surprisingly, by binding to the ATP synthase α subunit, which acts inside of mitochondria and independently of ATP synthase. We also demonstrated the conservation of this mechanism in mammalian cells. This study reveals a distinct paradigm for the &quot;iron tug of war&quot; between commensal bacteria and their hosts and an important mechanism for mitochondrial iron uptake and homeostasis.},
}
@article {pmid30145935,
year = {2018},
author = {Nagabhyru, P and Dinkins, RD and Schardl, CL},
title = {Transcriptomics of Epichloë-Grass Symbioses in Host Vegetative and Reproductive Stages.},
journal = {Molecular plant-microbe interactions : MPMI},
volume = {},
number = {},
pages = {MPMI10170251R},
doi = {10.1094/MPMI-10-17-0251-R},
pmid = {30145935},
issn = {0894-0282},
abstract = {Epichloë species are fungal symbionts (endophytes) of cool-season grasses that transmit vertically via inflorescence primordia (IP), ovaries (OV), and ultimately, embryos. Epichloë coenophiala, an endophyte of tall fescue (Schedonorus arundinaceus), provides multiple protective benefits to the grass. We conducted transcriptome analysis of the tall fescue-E. coenophiala symbiosis, comparing IP, OV, vegetative pseudostems (PS), and the lemma and palea (LP) (bracts) of the young floret. Transcriptomes of host OV and PS exhibited almost no significant differences attributable to endophyte presence or absence. Comparison of endophyte gene expression in different plant parts revealed numerous differentially expressed genes (DEGs). The 150 endophyte DEGs significantly higher in PS over OV included genes for alkaloid biosynthesis and sugar or amino acid transport. The 277 endophyte DEGs significantly higher in OV over PS included genes for protein chaperones (including most heat-shock proteins), trehalose synthesis complex, a bax inhibitor-1 protein homolog, the CLC chloride ion channel, catalase, and superoxide dismutase. Similar trends were apparent in the Brachypodium sylvaticum-Epichloë sylvatica symbiosis. Gene expression profiles in tall fescue IP and LP indicated that the endophyte transcriptome shift began early in host floral development. We discuss possible roles of the endophyte DEGs in colonization of reproductive grass tissues.},
}
@article {pmid30145614,
year = {2018},
author = {Tyburska-Woś, J and Nowak, K and Kieliszewska-Rokicka, B},
title = {Influence of leaf damage by the horse chestnut leafminer (Cameraria ohridella Deschka &amp; Dimić) on mycorrhiza of Aesculus hippocastanum L.},
journal = {Mycorrhiza},
volume = {},
number = {},
pages = {},
doi = {10.1007/s00572-018-0862-8},
pmid = {30145614},
issn = {1432-1890},
abstract = {In many parts of Europe, the white horse chestnut (Aesculus hippocastanum L.) has been attacked by the horse chestnut leafminer (Cameraria ohridella Deschka &amp; Dimić), which causes premature leaf dieback. A. hippocastanum L. establishes mutualistic symbiosis with arbuscular mycorrhizal (AM) fungi. This study involved a comparison of mature A. hippocastanum individuals susceptible to C. ohridella and individuals resistant to this insect after a one-time treatment with a chemical preparation injected into the tree trunks 7 years before the investigation began. Concentration of macronutrients in soil and the activity of soil nonspecific dehydrogenase did not differ between soils under canopies of the treated and untreated trees. Concentrations of C and N were significantly higher in leaves of the treated than those of the untreated trees. The infestation by C. ohridella and defoliation of leaves of the untreated trees did not significantly influence the frequency and intensity of AM colonization compared to the chemically treated trees, although a tendency towards higher average AM colonization of roots of the untreated trees, infested by the herbivores, than roots of the non-infested trees was observed. The results also indicated a tendency for higher biomass of fine roots per soil volume under the trees treated against C. ohridella than under the trees invaded by the insect.},
}
@article {pmid30145046,
year = {2018},
author = {De Meyer, SE and Ruthrof, KX and Edwards, T and Hopkins, AJM and Hardy, G and O'Hara, G and Howieson, J},
title = {Diversity of endemic rhizobia on Christmas Island: Implications for agriculture following phosphate mining.},
journal = {Systematic and applied microbiology},
volume = {41},
number = {6},
pages = {641-649},
doi = {10.1016/j.syapm.2018.07.004},
pmid = {30145046},
issn = {1618-0984},
abstract = {Given that phosphate supplies may diminish and become uneconomic to mine after 2020, there is a compelling need to develop alternative industries to support the population on Christmas Island. Former mine sites could be turned into productive agricultural land, however, large-scale commercial agriculture has never been attempted, and, given the uniqueness of the island, the diversity of rhizobia prior to introducing legumes needed evaluation. Therefore, 84 rhizobia isolates were obtained from nine different hosts, both crop and introduced legumes, located at seven sites across the island. Based on 16S rRNA and recA gene sequence analysis, the isolates grouped into 13 clades clustering within the genus Bradyrhizobium, Ensifer, Cupriavidus and Rhizobium. According to the sequences of their symbiosis genes nodC and nifH, the isolates were classified into 12 and 11 clades, respectively, and clustered closest to tropical or crop legume isolates. Moreover, the symbiosis gene phylogeny and Multi Locus Sequence Analysis gene phylogeny suggested vertical transmission in the Alpha-rhizobia but horizontal transmission within the Beta-rhizobia. Furthermore, this study provides evidence of a large diversity of endemic rhizobia associated with both crop and introduced legumes, and highlights the necessity of inoculation for common bean, chickpea and soybean on the Island.},
}
@article {pmid30141128,
year = {2018},
author = {Li, H and Mishra, M and Ding, S and Miyamoto, MM},
title = {Diversity and Dynamics of &quot;Candidatus Endobugula&quot; and Other Symbiotic Bacteria in Chinese Populations of the Bryozoan, Bugula neritina.},
journal = {Microbial ecology},
volume = {},
number = {},
pages = {},
doi = {10.1007/s00248-018-1233-x},
pmid = {30141128},
issn = {1432-184X},
support = {201205024-2//Public Welfare Project of the State Oceanic Administration/ ; 2013FY110700//National Basic Research Foundation of China/ ; },
abstract = {Bugula neritina is a common invasive cosmopolitan bryozoan that harbors (like many sessile marine invertebrates) a symbiotic bacterial (SB) community. Among the SB of B. neritina, &quot;Candidatus Endobugula sertula&quot; continues to receive the greatest attention, because it is the source of bryostatins. The bryostatins are potent bioactive polyketides, which have been investigated for their therapeutic potential to treat various cancers, Alzheimer's disease, and AIDS. In this study, we compare the metagenomics sequences for the 16S ribosomal RNA gene of the SB communities from different geographic and life cycle samples of Chinese B. neritina. Using a variety of approaches for estimating alpha/beta diversity and taxonomic abundance, we find that the SB communities vary geographically with invertebrate and fish mariculture and with latitude and environmental temperature. During the B. neritina life cycle, we find that the diversity and taxonomic abundances of the SB communities change with the onset of host metamorphosis, filter feeding, colony formation, reproduction, and increased bryostatin production. &quot;Ca. Endobugula sertula&quot; is confirmed as the symbiont of the Chinese &quot;Ca. Endobugula&quot;/B. neritina symbiosis. Our study extends our knowledge about B. neritina symbiosis from the New to the Old World and offers new insights into the environmental and life cycle factors that can influence its SB communities, &quot;Ca. Endobugula,&quot; and bryostatins more globally.},
}
@article {pmid30140262,
year = {2018},
author = {Rosenblueth, M and Ormeño-Orrillo, E and López-López, A and Rogel, MA and Reyes-Hernández, BJ and Martínez-Romero, JC and Reddy, PM and Martínez-Romero, E},
title = {Nitrogen Fixation in Cereals.},
journal = {Frontiers in microbiology},
volume = {9},
number = {},
pages = {1794},
doi = {10.3389/fmicb.2018.01794},
pmid = {30140262},
issn = {1664-302X},
abstract = {Cereals such as maize, rice, wheat and sorghum are the most important crops for human nutrition. Like other plants, cereals associate with diverse bacteria (including nitrogen-fixing bacteria called diazotrophs) and fungi. As large amounts of chemical fertilizers are used in cereals, it has always been desirable to promote biological nitrogen fixation in such crops. The quest for nitrogen fixation in cereals started long ago with the isolation of nitrogen-fixing bacteria from different plants. The sources of diazotrophs in cereals may be seeds, soils, and even irrigation water and diazotrophs have been found on roots or as endophytes. Recently, culture-independent molecular approaches have revealed that some rhizobia are found in cereal plants and that bacterial nitrogenase genes are expressed in plants. Since the levels of nitrogen-fixation attained with nitrogen-fixing bacteria in cereals are not high enough to support the plant's needs and never as good as those obtained with chemical fertilizers or with rhizobium in symbiosis with legumes, it has been the aim of different studies to increase nitrogen-fixation in cereals. In many cases, these efforts have not been successful. However, new diazotroph mutants with enhanced capabilities to excrete ammonium are being successfully used to promote plant growth as commensal bacteria. In addition, there are ambitious projects supported by different funding agencies that are trying to genetically modify maize and other cereals to enhance diazotroph colonization or to fix nitrogen or to form nodules with nitrogen-fixing symbiotic rhizobia.},
}
@article {pmid30140257,
year = {2018},
author = {Xu, L and Wu, C and Oelmüller, R and Zhang, W},
title = {Role of Phytohormones in Piriformospora indica-Induced Growth Promotion and Stress Tolerance in Plants: More Questions Than Answers.},
journal = {Frontiers in microbiology},
volume = {9},
number = {},
pages = {1646},
doi = {10.3389/fmicb.2018.01646},
pmid = {30140257},
issn = {1664-302X},
abstract = {Phytohormones play vital roles in the growth and development of plants as well as in interactions of plants with microbes such as endophytic fungi. The endophytic root-colonizing fungus Piriformospora indica promotes plant growth and performance, increases resistance of colonized plants to pathogens, insects and abiotic stress. Here, we discuss the roles of the phytohormones (auxins, cytokinin, gibberellins, abscisic acid, ethylene, salicylic acid, jasmonates, and brassinosteroids) in the interaction of P. indica with higher plant species, and compare available data with those from other (beneficial) microorganisms interacting with roots. Crosstalks between different hormones in balancing the plant responses to microbial signals is an emerging topic in current research. Furthermore, phytohormones play crucial roles in systemic signal propagation as well as interplant communication. P. indica interferes with plant hormone synthesis and signaling to stimulate growth, flowering time, differentiation and local and systemic immune responses. Plants adjust their hormone levels in the roots in response to the microbes to control colonization and fungal propagation. The available information on the roles of phytohormones in beneficial root-microbe interactions opens new questions of how P. indica manipulates the plant hormone metabolism to promote the benefits for both partners in the symbiosis.},
}
@article {pmid30140050,
year = {2018},
author = {Krueger, T and Bodin, J and Horwitz, N and Loussert-Fonta, C and Sakr, A and Escrig, S and Fine, M and Meibom, A},
title = {Temperature and feeding induce tissue level changes in autotrophic and heterotrophic nutrient allocation in the coral symbiosis - A NanoSIMS study.},
journal = {Scientific reports},
volume = {8},
number = {1},
pages = {12710},
doi = {10.1038/s41598-018-31094-1},
pmid = {30140050},
issn = {2045-2322},
abstract = {Corals access inorganic seawater nutrients through their autotrophic endosymbiotic dinoflagellates, but also capture planktonic prey through heterotrophic feeding. Correlating NanoSIMS and TEM imaging, we visualized and quantified the subcellular fate of autotrophic and heterotrophic C and N in the coral Stylophora pistillata using stable isotopes. Six scenarios were compared after 6 h: autotrophic pulse (13C-bicarbonate, 15N-nitrate) in either unfed or regularly fed corals, and heterotrophic pulse (13C-, 15N-labelled brine shrimps) in regularly fed corals; each at ambient and elevated temperature. Host assimilation of photosynthates was similar under fed and unfed conditions, but symbionts assimilated 10% more C in fed corals. Photoautotrophic C was primarily channelled into host lipid bodies, whereas heterotrophic C and N were generally co-allocated to the tissue. Food-derived label was detected in some subcellular structures associated with the remobilisation of host lipid stores. While heterotrophic input generally exceeded autotrophic input, it was more negatively affected by elevated temperature. The reduced input from both modes of nutrition at elevated temperature was accompanied by a shift in the partitioning of C and N, benefiting epidermis and symbionts. This study provides a unique view into the nutrient partitioning in corals and highlights the tight connection of nutrient fluxes in symbiotic partners.},
}
@article {pmid30137308,
year = {2018},
author = {Shi, PQ and Wang, L and Liu, Y and An, X and Chen, XS and Ahmed, MZ and Qiu, BL and Sang, W},
title = {Infection dynamics of endosymbionts reveal three novel localization patterns of Rickettsia during the development of whitefly Bemisia tabaci.},
journal = {FEMS microbiology ecology},
volume = {94},
number = {11},
pages = {},
doi = {10.1093/femsec/fiy165},
pmid = {30137308},
issn = {1574-6941},
abstract = {The whitefly Bemisia tabaci (Hemiptera: Aleyrodidae) is a severe agricultural pest that harbors at least seven endosymbionts. Many important aspects of the symbiosis mechanism between these bacterial endosymbionts and their hosts are poorly understood, such as endosymbiont proliferation dynamics, spatial distribution and titer regulation during host development. In this study, infection by bacterial endosymbionts in the whitefly B. tabaci Middle East-Asia Minor-1 (MEAM1, formerly B biotype) South China population, their infection titers in various stages of whitefly host development and their spatial localization were investigated. Results revealed that the MEAM1 B. tabaci harbors the primary symbiont Portiera and secondary symbionts Rickettsia and Hamiltonella. The titers of these three endosymbionts increased with the development of their B. tabaci host. Significant proliferation of Portiera and Hamiltonella mainly occurred during the second to fourth instar nymphal stages, while Rickettsia proliferated mainly during adult eclosion. Fluorescence in situ hybridization analysis of B. tabaci adults revealed three novel infection patterns of Rickettsia: assemblage in the bacteriocytes that scattered through the entire abdomen of the female host, localization in wax glands and localization in the colleterial gland. These novel infection patterns may help to uncover the function of Rickettsia in its insect hosts.},
}
@article {pmid30136892,
year = {2018},
author = {Sorroche, F and Bogino, P and Russo, DM and Zorreguieta, A and Nievas, F and Morales, GM and Hirsch, AM and Giordano, W},
title = {Cell Autoaggregation, Biofilm Formation, and Plant Attachment in a Sinorhizobium meliloti lpsB Mutant.},
journal = {Molecular plant-microbe interactions : MPMI},
volume = {31},
number = {10},
pages = {1075-1082},
doi = {10.1094/MPMI-01-18-0004-R},
pmid = {30136892},
issn = {0894-0282},
mesh = {Bacterial Adhesion ; Bacterial Proteins/genetics/*metabolism ; Biofilms/*growth &amp; development ; Gene Expression Regulation, Bacterial/*physiology ; Mannosyltransferases/genetics/*metabolism ; Mutation ; Sinorhizobium meliloti/*genetics/*physiology ; },
abstract = {Bacterial surface molecules are crucial for the establishment of a successful rhizobia-legume symbiosis, and, in most bacteria, are also critical for adherence properties, surface colonization, and as a barrier for defense. Rhizobial mutants defective in the production of exopolysaccharides (EPSs), lipopolysaccharides (LPSs), or capsular polysaccharides are usually affected in symbiosis with their plant hosts. In the present study, we evaluated the role of the combined effects of LPS and EPS II in cell-to-cell and cell-to-surface interactions in Sinorhizobium meliloti by studying planktonic cell autoaggregation, biofilm formation, and symbiosis with the host plant Medicago sativa. The lpsB mutant, which has a defective core portion of LPS, exhibited a reduction in biofilm formation on abiotic surfaces as well as altered biofilm architecture compared with the wild-type Rm8530 strain. Atomic force microscopy and confocal laser microscopy revealed an increase in polar cell-to-cell interactions in the lpsB mutant, which might account for the biofilm deficiency. However, a certain level of biofilm development was observed in the lpsB strain compared with the EPS II-defective mutant strains. Autoaggregation experiments carried out with LPS and EPS mutant strains showed that both polysaccharides have an impact on the cell-to-cell adhesive interactions of planktonic bacteria. Although the lpsB mutation and the loss of EPS II production strongly stimulated early attachment to alfalfa roots, the number of nodules induced in M. sativa was not increased. Taken together, this work demonstrates that S. meliloti interactions with biotic and abiotic surfaces depend on the interplay between LPS and EPS II.},
}
@article {pmid30136358,
year = {2018},
author = {Koehler, S and Gaedeke, R and Thompson, C and Bongrand, C and Visick, KL and Ruby, E and McFall-Ngai, M},
title = {The model squid-vibrio symbiosis provides a window into the impact of strain- and species-level differences during the initial stages of symbiont engagement.},
journal = {Environmental microbiology},
volume = {},
number = {},
pages = {},
doi = {10.1111/1462-2920.14392},
pmid = {30136358},
issn = {1462-2920},
support = {R01 AI050661/AI/NIAID NIH HHS/United States ; R37 AI150661//National Institute of Health/ ; GM114288//National Institute of Health/ ; R01 OD011024/OD/NIH HHS/United States ; R37 AI050661/AI/NIAID NIH HHS/United States ; R01 OD11024//National Institute of Health/ ; },
abstract = {Among horizontally acquired symbioses, the mechanisms underlying microbial strain- and species-level specificity remain poorly understood. Here, confocal-microscopy analyses and genetic manipulation of the squid-vibrio association revealed quantitative differences in a symbiont's capacity to interact with the host during initial engagement. Specifically, dominant strains of Vibrio fischeri, 'D-type', previously named for their dominant, single-strain colonization of the squid's bioluminescent organ, were compared with 'S-type', or 'sharing', strains, which can co-colonize the organ. These D-type strains typically: (i) formed aggregations of 100s-1000s of cells on the light-organ surface, up to 3 orders of magnitude larger than those of S-type strains; (ii) showed dominance in co-aggregation experiments, independent of inoculum size or strain proportion; (iii) perturbed larger areas of the organ's ciliated surface; and, (iv) appeared at the pore of the organ approximately 4×s more quickly than S-type strains. At least in part, genes responsible for biofilm synthesis control the hyperaggregation phenotype of a D-type strain. Other marine vibrios produced relatively small aggregations, while an array of marine Gram-positive and -negative species outside of the Vibrionaceae did not attach to the organ's surface. These studies provide insight into the impact of strain variation on early events leading to establishment of an environmentally acquired symbiosis.},
}
@article {pmid30135694,
year = {2018},
author = {Mens, C and Li, D and Haaima, LE and Gresshoff, PM and Ferguson, BJ},
title = {Local and Systemic Effect of Cytokinins on Soybean Nodulation and Regulation of Their Isopentenyl Transferase (IPT) Biosynthesis Genes Following Rhizobia Inoculation.},
journal = {Frontiers in plant science},
volume = {9},
number = {},
pages = {1150},
doi = {10.3389/fpls.2018.01150},
pmid = {30135694},
issn = {1664-462X},
abstract = {Cytokinins are important regulators of cell proliferation and differentiation in plant development. Here, a role for this phytohormone group in soybean nodulation is shown through the exogenous application of cytokinins (6-benzylaminopurine, N6-(Δ2-isopentenyl)-adenine and trans-zeatin) via either root drenching or a petiole feeding technique. Overall, nodule numbers were reduced by treatment with high cytokinin concentrations, but increased with lower concentrations. This was especially evident when feeding the solutions directly into the vasculature via petiole feeding. These findings highlight the importance of cytokinin in nodule development. To further investigate the role of cytokinin in controlling nodule numbers, the IPT gene family involved in cytokinin biosynthesis was characterized in soybean. Bioinformatic analyses identified 17 IPT genes in the soybean genome and homeologous duplicate gene partners were subsequently identified including GmIPT5 and GmIPT6, the orthologs of LjIPT3. Expression of GmIPT5 was upregulated in the shoot in response to nodulation, but this was independent of a functional copy of the autoregulation of nodulation (AON) receptor, GmNARK, which suggests it is unlikely to have a role in the negative feedback system called AON. Legumes also control nodule numbers in the presence of soil nitrogen through nitrate-dependent regulation of nodulation, a locally acting pathway in soybean. Upon nitrate treatment to the root, the tandem duplicates GmIPT3 and GmIPT15 were upregulated in expression indicating a role for these genes in the plant's response to soil nitrogen, potentially including the nitrate-dependent regulation of legume nodulation pathway. Additional roles for cytokinin and their IPT biosynthetic genes in nodulation and the control of nodule numbers are discussed.},
}
@article {pmid30135586,
year = {2018},
author = {Hetherington, AJ and Dolan, L},
title = {Stepwise and independent origins of roots among land plants.},
journal = {Nature},
volume = {561},
number = {7722},
pages = {235-238},
doi = {10.1038/s41586-018-0445-z},
pmid = {30135586},
issn = {1476-4687},
abstract = {Roots are one of the three fundamental organ systems of vascular plants1, and have roles in anchorage, symbiosis, and nutrient and water uptake2-4. However, the fragmentary nature of the fossil record obscures the origins of roots and makes it difficult to identify when the sole defining characteristic of extant roots-the presence of self-renewing structures called root meristems that are covered by a root cap at their apex1-9-evolved. Here we report the discovery of what are-to our knowledge-the oldest meristems of rooting axes, found in the earliest-preserved terrestrial ecosystem10 (the 407-million-year-old Rhynie chert). These meristems, which belonged to the lycopsid Asteroxylon mackiei11-14, lacked root caps and instead developed a continuous epidermis over the surface of the meristem. The rooting axes and meristems of A. mackiei are unique among vascular plants. These data support the hypothesis that roots, as defined in extant vascular plants by the presence of a root cap7, were a late innovation in the vascular lineage. Roots therefore acquired traits in a stepwise fashion. The relatively late origin in lycophytes of roots with caps is consistent with the hypothesis that roots evolved multiple times2 rather than having a single origin1, and the extensive similarities between lycophyte and euphyllophyte roots15-18 therefore represent examples of convergent evolution. The key phylogenetic position of A. mackiei-with its transitional rooting organ-between early diverging land plants that lacked roots and derived plants that developed roots demonstrates how roots were 'assembled' during the course of plant evolution.},
}
@article {pmid30132699,
year = {2018},
author = {Greenway, A},
title = {Spore-forming bacteria in the gut: an interview with Hilary Browne.},
journal = {Future microbiology},
volume = {13},
number = {},
pages = {1077-1079},
doi = {10.2217/fmb-2018-0143},
pmid = {30132699},
issn = {1746-0921},
mesh = {Bacteria/*growth &amp; development/pathogenicity ; Bacterial Physiological Phenomena ; Gastrointestinal Tract/*microbiology ; Humans ; Spores, Bacterial/growth &amp; development/pathogenicity/*physiology ; Symbiosis ; },
abstract = {Hilary Browne speaks to Alice Greenway, Commissioning Editor of Future Microbiology, at the Microbiology Society Annual Conference 2018. Hilary Browne is a Staff Scientist at the Wellcome Sanger Institute in Cambridge (UK). His research focuses on culturing, curating and whole genome sequencing of the human gut microbiota and using these resources to study the human intestinal microbiota. At the Microbiology Society Annual Conference 2018, we asked him a few questions regarding his past and current research focuses, including the offered paper he presented at the conference entitled: 'Host adaptation of commensal bacteria through loss of sporulation and genome reduction'.},
}
@article {pmid30132292,
year = {2018},
author = {de la Torre, J and Banerjee, S and Baumgartner, J and Lin, GY and Burgoyne, AM and Kirane, A and Sicklick, J},
title = {Tumor Symbiosis: Gastrointestinal Stromal Tumor as a Host for Primary Peritoneal Mesothelioma.},
journal = {Journal of gastrointestinal surgery : official journal of the Society for Surgery of the Alimentary Tract},
volume = {},
number = {},
pages = {},
doi = {10.1007/s11605-018-3918-3},
pmid = {30132292},
issn = {1873-4626},
support = {K08 CA168999/CA/NCI NIH HHS/United States ; R21 CA192072/CA/NCI NIH HHS/United States ; K08CA168999//National Institutes of Health/ ; R21CA192072//National Institutes of Health/ ; },
}
@article {pmid30131883,
year = {2018},
author = {Xu, Y and Liu, F and Han, G and Wang, W and Zhu, S and Li, X},
title = {Improvement of Lotus japonicus hairy root induction and development of a mycorrhizal symbiosis system.},
journal = {Applications in plant sciences},
volume = {6},
number = {4},
pages = {e1141},
doi = {10.1002/aps3.1141},
pmid = {30131883},
issn = {2168-0450},
abstract = {Premise of the Study: We describe a highly efficient in vitro Lotus japonicus hairy root transformation system that is useful for the investigation of mycorrhizal symbiosis.<br><br>Methods and Results: The Agrobacterium rhizogenes-mediated transformation method was improved based on the binary plasmid (pCAMBIA 1304) harboring green fluorescent protein and β-glucuronidase genes for rapid detection. Transgenic hairy roots were grown within 13 days. These in vitro-cultured hairy roots can be inoculated with Rhizophagus irregularis, thus facilitating the investigation of the symbiosis between L. japonicus and arbuscular mycorrhizal fungi.<br><br>Conclusions: Compared with existing techniques, our protocol provides a simple and efficient A. rhizogenes-mediated transformation system for L. japonicus. The rapid induction of hairy roots can shorten the experimental time by at least one week.},
}
@article {pmid30131500,
year = {2018},
author = {Pfau, T and Christian, N and Masakapalli, SK and Sweetlove, LJ and Poolman, MG and Ebenhöh, O},
title = {The intertwined metabolism during symbiotic nitrogen fixation elucidated by metabolic modelling.},
journal = {Scientific reports},
volume = {8},
number = {1},
pages = {12504},
doi = {10.1038/s41598-018-30884-x},
pmid = {30131500},
issn = {2045-2322},
support = {222716//EC | Seventh Framework Programme (European Union Seventh Framework Programme)/ ; 316427//EC | Seventh Framework Programme (European Union Seventh Framework Programme)/ ; },
abstract = {Genome-scale metabolic network models can be used for various analyses including the prediction of metabolic responses to changes in the environment. Legumes are well known for their rhizobial symbiosis that introduces nitrogen into the global nutrient cycle. Here, we describe a fully compartmentalised, mass and charge-balanced, genome-scale model of the clover Medicago truncatula, which has been adopted as a model organism for legumes. We employed flux balance analysis to demonstrate that the network is capable of producing biomass components in experimentally observed proportions, during day and night. By connecting the plant model to a model of its rhizobial symbiont, Sinorhizobium meliloti, we were able to investigate the effects of the symbiosis on metabolic fluxes and plant growth and could demonstrate how oxygen availability influences metabolic exchanges between plant and symbiont, thus elucidating potential benefits of inter organism amino acid cycling. We thus provide a modelling framework, in which the interlinked metabolism of plants and nodules can be studied from a theoretical perspective.},
}
@article {pmid30129677,
year = {2018},
author = {Yu, H and Xiao, A and Dong, R and Fan, Y and Zhang, X and Liu, C and Wang, C and Zhu, H and Duanmu, D and Cao, Y and Zhang, Z},
title = {Suppression of innate immunity mediated by the CDPK-Rboh complex is required for rhizobial colonization in Medicago truncatula nodules.},
journal = {The New phytologist},
volume = {220},
number = {2},
pages = {425-434},
doi = {10.1111/nph.15410},
pmid = {30129677},
issn = {1469-8137},
support = {//Start Funding from Huazhong Agricultural University (HZAU) and &quot;One Thousand&quot; Talent Plan Young Professional Program/ ; 31670240//National Natural Science Foundation of China/ ; 2662015PY165//Fundamental Research Funds for the Central Universities/ ; 2016YF0100700//The National Key R&amp;D Program of China/ ; 2014BS23//Huazhong Agricultural University Independent Scientific &amp; Technological Innovation Foundation/ ; },
abstract = {Suppression of innate immunity is essential for rhizobial infection and colonization in compatible interactions with leguminous plants. In Medicago nad1 mutant plants, innate immunity is excessively activated, resulting in necrotic cell death after rhizobia are released from infection threads into symbiotic cells, suggesting that innate immunity plays a critical role in regulating bacteroid persistence. In this study, we identified three respiratory burst oxidase homologs (Rboh) and one calcium-dependent protein kinase (CDPK) as key factors for the activation of immunity in Medicago nodules using genetic and biochemical methods. Knock-out of either MtRbohB or MtRbohD in nad1-1 mutant plants produced effective nodules with intact symbiotic cells, while knock-out of MtRbohC decreased brown pigment deposition, leading to less necrosis in nad1-1 mutant nodules. MtCDPK5 directly phosphorylated MtRbohB, MtRbohC and MtRbohD, which triggered immune responses in plants. Knock-out of MtCDPK5 in nad1-1 mutant plants partially restored nitrogen-fixing nodules. Overexpression of the constitutively activated variant MtCDPK5VK under the control of the NAD1 promoter elicited strong immune responses, resulting in ineffective nodules in wild-type plants. Our data provide direct evidence that host plants utilize innate immunity to regulate rhizobial colonization in symbiotic cells in Medicago truncatula.},
}
@article {pmid30128189,
year = {2018},
author = {Anderson, EE and Wilson, C and Knap, AH and Villareal, TA},
title = {Summer diatom blooms in the eastern North Pacific gyre investigated with a long-endurance autonomous surface vehicle.},
journal = {PeerJ},
volume = {6},
number = {},
pages = {e5387},
doi = {10.7717/peerj.5387},
pmid = {30128189},
issn = {2167-8359},
abstract = {Satellite chlorophyll a (chl a) observations have repeatedly noted summertime phytoplankton blooms in the North Pacific subtropical gyre (NPSG), a region of open ocean that is far removed from any land-derived or Ekman upwelling nutrient sources. These blooms are dominated by N2-fixing diatom-cyanobacteria associations of the diatom genera Rhizosolenia Brightwell and Hemiaulus Ehrenberg. Their nitrogen fixing endosymbiont, Richelia intracellularis J.A. Schmidt, is hypothesized to be critical to the development of blooms in this nitrogen limited region. However, due to the remote location and unpredictable duration of the summer blooms, prolonged in situ observations are rare outside of the Station ALOHA time-series off of Hawai'i. In summer, 2015, a proof-of-concept mission using the autonomous vehicle, Honey Badger (Wave Glider SV2; Liquid Robotics, a Boeing company, Sunnyvale, CA, USA), collected near-surface (<20 m) observations in the NPSG using hydrographic, meteorological, optical, and imaging sensors designed to focus on phytoplankton abundance, distribution, and physiology of this bloom-forming region. Hemiaulus and Rhizosolenia cell abundance was determined using digital holography for the entire June-November mission. Honey Badger was not able to reach the 30°N subtropical front region where most of the satellite chl a blooms have been observed, but near-real time navigational control allowed it to transect two blooms near 25°N. The two taxa did not co-occur in large numbers, rather the blooms were dominated by either Hemiaulus or Rhizosolenia. The August 2-4, 2015 bloom was comprised of 96% Hemiaulus and the second bloom, August 15-17, 2015, was dominated by Rhizosolenia (75%). The holograms also imaged undisturbed, fragile Hemiaulus aggregates throughout the sampled area at ∼10 L-1. Aggregated Hemiaulus represented the entire observed population at times and had a widespread distribution independent of the summer export pulse, a dominant annual event suggested to be mediated by aggregate fluxes. Aggregate occurrence was not consistent with a density dependent formation mechanism and may represent a natural growth form in undisturbed conditions. The photosynthetic potential index (Fv:Fm) increased from ∼0.4 to ∼0.6 during both blooms indicating a robust, active phytoplankton community in the blooms. The diel pattern of Fv:Fm (nocturnal maximum; diurnal minimum) was consistent with macronutrient limitation throughout the mission with no evidence of Fe-limitation despite the presence of nitrogen fixing diatom-diazotroph assemblages. During the 5-month mission, Honey Badger covered ∼5,690 km (3,070 nautical miles), acquired 9,336 holograms, and reliably transmitted data onshore in near real-time. Software issues developed with the active fluorescence sensor that terminated measurements in early September. Although images were still useful at the end of the mission, fouling of the LISST-Holo optics was considerable, and appeared to be the most significant issue facing deployments of this duration.},
}
@article {pmid30127013,
year = {2018},
author = {Speare, L and Cecere, AG and Guckes, KR and Smith, S and Wollenberg, MS and Mandel, MJ and Miyashiro, T and Septer, AN},
title = {Bacterial symbionts use a type VI secretion system to eliminate competitors in their natural host.},
journal = {Proceedings of the National Academy of Sciences of the United States of America},
volume = {115},
number = {36},
pages = {E8528-E8537},
doi = {10.1073/pnas.1808302115},
pmid = {30127013},
issn = {1091-6490},
support = {R00 GM097032/GM/NIGMS NIH HHS/United States ; R35 GM119627/GM/NIGMS NIH HHS/United States ; R21 AI117262/AI/NIAID NIH HHS/United States ; },
mesh = {Aliivibrio fischeri/isolation &amp; purification/*physiology ; Animals ; Decapodiformes/*microbiology ; Symbiosis/*physiology ; *Type IV Secretion Systems/genetics/metabolism ; },
abstract = {Intraspecific competition describes the negative interaction that occurs when different populations of the same species attempt to fill the same niche. Such competition is predicted to occur among host-associated bacteria but has been challenging to study in natural biological systems. Although many bioluminescent Vibrio fischeri strains exist in seawater, only a few strains are found in the light-organ crypts of an individual wild-caught Euprymna scolopes squid, suggesting a possible role for intraspecific competition during early colonization. Using a culture-based assay to investigate the interactions of different V. fischeri strains, we found &quot;lethal&quot; and &quot;nonlethal&quot; isolates that could kill or not kill the well-studied light-organ isolate ES114, respectively. The killing phenotype of these lethal strains required a type VI secretion system (T6SS) encoded in a 50-kb genomic island. Multiple lethal and nonlethal strains could be cultured from the light organs of individual wild-caught adult squid. Although lethal strains eliminate nonlethal strains in vitro, two lethal strains could coexist in interspersed microcolonies that formed in a T6SS-dependent manner. This coexistence was destabilized upon physical mixing, resulting in one lethal strain consistently eliminating the other. When juvenile squid were coinoculated with lethal and nonlethal strains, they occupied different crypts, yet they were observed to coexist within crypts when T6SS function was disrupted. These findings, using a combination of natural isolates and experimental approaches in vitro and in the animal host, reveal the importance of T6SS in spatially separating strains during the establishment of host colonization in a natural symbiosis.},
}
@article {pmid30126254,
year = {2018},
author = {Sandaa, RA and Bratbak, G},
title = {Is the Virus Important? And Some Other Questions.},
journal = {Viruses},
volume = {10},
number = {8},
pages = {},
doi = {10.3390/v10080442},
pmid = {30126254},
issn = {1999-4915},
mesh = {Chlorella/*virology ; Paramecium/*physiology ; Phycodnaviridae/classification/*genetics/isolation &amp; purification ; Phylogeny ; Seawater ; Symbiosis ; Terminology as Topic ; },
abstract = {The motivation for focusing on a specific virus is often its importance in terms of impact on human interests. The chlorella viruses are a notable exception and 40 years of research has made them the undisputed model system for large icosahedral dsDNA viruses infecting eukaryotes. Their status has changed from inconspicuous and rather odd with no ecological relevance to being the Phycodnaviridae type strain possibly affecting humans and human cognitive functioning in ways that remain to be understood. The Van Etten legacy is the backbone for research on Phycodnaviridae. After highlighting some of the peculiarities of chlorella viruses, we point to some issues and questions related to the viruses we choose for our research, our prejudices, what we are still missing, and what we should be looking for.},
}
@article {pmid30121874,
year = {2018},
author = {Dastogeer, KMG},
title = {Influence of fungal endophytes on plant physiology is more pronounced under stress than well-watered conditions: a meta-analysis.},
journal = {Planta},
volume = {248},
number = {6},
pages = {1403-1416},
doi = {10.1007/s00425-018-2982-y},
pmid = {30121874},
issn = {1432-2048},
abstract = {MAIN CONCLUSION: A meta-analysis of published articles shows that the influence of fungal endophytes on plant performance is dependent on plant water status. The magnitude of endophytic effects is higher in plants grown in water-limiting environments than those in adequate watering environments. The outcome of plant-endophyte interactions depends on the identity of the plant host and fungal symbionts. Water limitation often hinders plant productivity in both natural and agricultural settings. Endophytic fungal symbionts can mediate plant water stress responses by enhancing drought tolerance and avoidance, but these effects have not been quantified across plant-endophyte studies. A meta-analysis of published studies was performed to determine how endophytic fungal symbionts influence plant response under non-stressed versus water-stressed conditions. A significantly positive or neutral overall effect of fungal endophyte was noted under water-stressed conditions. In contrast, under non-stressed conditions, the overall effect of fungi on plants was mostly neutral. In general, the presence of fungal endophytes increased plant's total biomass, chlorophyll content, and stomatal conductance irrespective of water availability. In addition, plant shoot biomass, tiller density, plant height, maximum quantum yield (Fv/Fm), net photosynthesis, relative water content (RWC), amounts of ascorbate peroxidase (APX), glutathione (GSH), polyphenol oxidase (PPO), superoxide dismutase (SOD), and phenolics were significantly increased by endophyte colonisation under stressed conditions. Malondialdehyde (MDA) and hydrogen peroxide (H2O2) were reduced in endophytic plants under stress as compared with non-endophytic counterparts. Categorical analysis revealed that accumulation in plant biomass is influenced by factors such as host and fungi identity, the magnitude of which is greater under stressed than non-stressed conditions.},
}
@article {pmid30120864,
year = {2018},
author = {Pfeilmeier, S and George, J and Morel, A and Roy, S and Smoker, M and Stransfeld, L and Downie, JA and Peeters, N and Malone, JG and Zipfel, C},
title = {Expression of the Arabidopsis thaliana immune receptor EFR in Medicago truncatula reduces infection by a root pathogenic bacterium, but not nitrogen-fixing rhizobial symbiosis.},
journal = {Plant biotechnology journal},
volume = {},
number = {},
pages = {},
doi = {10.1111/pbi.12999},
pmid = {30120864},
issn = {1467-7652},
support = {//Norwich Research Park/ ; BB/J004553/1//BBSRC Institute Strategic Program/ ; //Gatsby Charitable Foundation/ ; ANR-10-LABX-41//Laboratoire d'Excellence (LABEX) TULIP/ ; },
abstract = {Interfamily transfer of plant pattern recognition receptors (PRRs) represents a promising biotechnological approach to engineer broad-spectrum, and potentially durable, disease resistance in crops. It is however unclear whether new recognition specificities to given pathogen-associated molecular patterns (PAMPs) affect the interaction of the recipient plant with beneficial microbes. To test this in a direct reductionist approach, we transferred the Brassicaceae-specific PRR ELONGATION FACTOR-THERMO UNSTABLE RECEPTOR (EFR), conferring recognition of the bacterial EF-Tu protein, from Arabidopsis thaliana to the legume Medicago truncatula. Constitutive EFR expression led to EFR accumulation and activation of immune responses upon treatment with the EF-Tu-derived elf18 peptide in leaves and roots. The interaction of M. truncatula with the bacterial symbiont Sinorhizobium meliloti is characterized by the formation of root nodules that fix atmospheric nitrogen. Although nodule numbers were slightly reduced at an early stage of the infection in EFR-Medicago when compared to control lines, nodulation was similar in all lines at later stages. Furthermore, nodule colonization by rhizobia, and nitrogen fixation were not compromised by EFR expression. Importantly, the M. truncatula lines expressing EFR were substantially more resistant to the root bacterial pathogen Ralstonia solanacearum. Our data suggest that the transfer of EFR to M. truncatula does not impede root nodule symbiosis, but has a positive impact on disease resistance against a bacterial pathogen. In addition, our results indicate that Rhizobium can either avoid PAMP recognition during the infection process, or is able to actively suppress immune signaling.},
}
@article {pmid30120506,
year = {2018},
author = {Aliverdi, A and Ahmadvand, G},
title = {Herbicide Toxicity to Soybean-Rhizobium Symbiosis as Affected by Soil pH.},
journal = {Bulletin of environmental contamination and toxicology},
volume = {101},
number = {4},
pages = {434-438},
doi = {10.1007/s00128-018-2417-2},
pmid = {30120506},
issn = {1432-0800},
mesh = {Benzothiadiazines/toxicity ; Herbicides/*toxicity ; Nitrogen Fixation ; Rhizobium/*physiology ; Soil/*chemistry ; Soil Microbiology ; Soybeans/*drug effects/*microbiology/physiology ; Symbiosis ; Triazines/toxicity ; Trifluralin/toxicity ; },
abstract = {The current study examined whether soil pH could influence the toxicity of herbicides to soybean-rhizobium symbiosis. This can be useful for farmers to minimize the toxicity of them to crop-rhizobium symbiosis via applying their reduced doses. The toxicity of bentazon, metribuzin, and trifluralin to soybean-rhizobium symbiosis was investigated in pH 6.4, 7.2, and 8 soils. Seed inoculation decreased shoot:root (S:R) ratio but increased height, shoot dry weight (SDW), root dry weight (RDW), shoot nitrogen content (SNC), root nitrogen content (RNC), and nitrogen fixation effectiveness (NFE) in the pH 7.2 soil without herbicide application. All herbicides decreased NFE in all soil pH regimes except metribuzin in the pH 6.4 soil. Unlike trifluralin, the toxicity of bentazon and metribuzin to soybean-rhizobium symbiosis was influenced by the soil pH. It can be concluded that soil acidification and alkalization, which can rapidly occur in agroecosystems, can decrease and increase the toxicity of bentazon and metribuzin to soybean-rhizobium symbiosis, respectively.},
}
@article {pmid30120198,
year = {2018},
author = {Xu, CC and Zhang, D and Hann, DR and Xie, ZP and Staehelin, C},
title = {Biochemical properties and in planta effects of NopM, a rhizobial E3 ubiquitin ligase.},
journal = {The Journal of biological chemistry},
volume = {293},
number = {39},
pages = {15304-15315},
doi = {10.1074/jbc.RA118.004444},
pmid = {30120198},
issn = {1083-351X},
abstract = {Nodulation outer protein M (NopM) is an IpaH family type three (T3) effector secreted by the nitrogen-fixing nodule bacterium Sinorhizobium sp. strain NGR234. Previous work indicated that NopM is an E3 ubiquitin ligase required for an optimal symbiosis between NGR234 and the host legume Lablab purpureus Here, we continued to analyze the function of NopM. Recombinant NopM was biochemically characterized using an in vitro ubiquitination system with Arabidopsis thaliana proteins. In this assay, NopM forms unanchored polyubiquitin chains and possesses auto-ubiquitination activity. In a NopM variant lacking any lysine residues, auto-ubiquitination was not completely abolished, indicating noncanonical auto-ubiquitination of the protein. In addition, we could show intermolecular ubiquitin transfer from NopM to C338A (enzymatically inactive NopM form) in vitro Bimolecular fluorescence complementation analysis provided clues about NopM-NopM interactions at plasma membranes in planta NopM, but not C338A, expressed in tobacco cells induced cell death, suggesting that E3 ubiquitin ligase activity of NopM induced effector-triggered immunity responses. Likewise, expression of NopM in Lotus japonicus caused reduced nodule formation, whereas expression of C338A showed no obvious effects on symbiosis. Further experiments indicated that serine residue 26 of NopM is phosphorylated in planta and that NopM can be phosphorylated in vitro by salicylic acid-induced protein kinase (NtSIPK), a mitogen-activated protein kinase (MAPK) of tobacco. Hence, NopM is a phosphorylated T3 effector that can interact with itself, with ubiquitin, and with MAPKs.},
}
@article {pmid30116782,
year = {2018},
author = {Li, Y and Liew, YJ and Cui, G and Cziesielski, MJ and Zahran, N and Michell, CT and Voolstra, CR and Aranda, M},
title = {DNA methylation regulates transcriptional homeostasis of algal endosymbiosis in the coral model Aiptasia.},
journal = {Science advances},
volume = {4},
number = {8},
pages = {eaat2142},
doi = {10.1126/sciadv.aat2142},
pmid = {30116782},
issn = {2375-2548},
abstract = {The symbiotic relationship between cnidarians and dinoflagellates is the cornerstone of coral reef ecosystems. Although research has focused on the molecular mechanisms underlying this symbiosis, the role of epigenetic mechanisms, that is, the study of heritable changes that do not involve changes in the DNA sequence, is unknown. To assess the role of DNA methylation in the cnidarian-dinoflagellate symbiosis, we analyzed genome-wide CpG methylation, histone associations, and transcriptomic states of symbiotic and aposymbiotic anemones in the model system Aiptasia. We found that methylated genes are marked by histone 3 lysine 36 trimethylation (H3K36me3) and show significant reduction of spurious transcription and transcriptional noise, revealing a role of DNA methylation in the maintenance of transcriptional homeostasis. Changes in DNA methylation and expression show enrichment for symbiosis-related processes, such as immunity, apoptosis, phagocytosis recognition, and phagosome formation, and reveal intricate interactions between the underlying pathways. Our results demonstrate that DNA methylation provides an epigenetic mechanism of transcriptional homeostasis that responds to symbiosis.},
}
@article {pmid30115324,
year = {2018},
author = {Taerum, SJ and de Beer, ZW and Marincowitz, S and Jankowiak, R and Wingfield, MJ},
title = {Ophiostoma quercus: An unusually diverse and globally widespread tree-infecting fungus.},
journal = {Fungal biology},
volume = {122},
number = {9},
pages = {900-910},
doi = {10.1016/j.funbio.2018.05.005},
pmid = {30115324},
issn = {1878-6146},
abstract = {Ophiostoma quercus (Ascomycota, Ophiostomatales) is a globally widespread, insect-vectored fungus that colonizes a wide diversity of hardwood and conifer hosts. Although the fungus is considered to be non-pathogenic, it is closely related to the fungi that cause Dutch elm disease. We examined the global diversity of O. quercus based on a ribosomal RNA marker and three unlinked gene regions. The fungus exhibited substantial morphological diversity. In addition, O. quercus had high genetic diversity in every continent from which it was collected, although the fungus was most diverse in Eurasia. There was no evidence of geographical clustering of haplotypes based on phylogenetic and network analyses. In addition, the phylogenetic trees generated based on the different markers were non-congruent. These results suggest that O. quercus has been repeatedly moved around the globe, because of trade in wood products, and that the fungal species most likely outcrosses regularly. The high genetic diversity of the fungus, as well as its ability to utilize a wide variety of arthropod vectors and colonize a tremendous diversity of tree host species makes O. quercus truly unique among ophiostomatoid fungi.},
}
@article {pmid30114664,
year = {2018},
author = {Filée, J},
title = {Giant viruses and their mobile genetic elements: the molecular symbiosis hypothesis.},
journal = {Current opinion in virology},
volume = {33},
number = {},
pages = {81-88},
doi = {10.1016/j.coviro.2018.07.013},
pmid = {30114664},
issn = {1879-6265},
abstract = {Among the virus world, Giant viruses (GVs) compose one of the most successful eukaryovirus families. By contrast with other eukaryoviruses, GV genomes contain a wide array of mobile genetic elements (MGEs) that encompass diverse, mostly prokaryotic-like, transposable element families, introns, inteins, restriction-modification systems and enigmatic classes of mobile elements having little similarities with known families. Interestingly, several of these MGEs may be beneficial to the GVs, fulfilling two kinds of functions: (1) degrading host or competing virus/virophage DNA and (2) promoting viral genome integration, dissemination and excision into the host genomes. By providing fitness advantages to the virus in which they reside, these MGEs compose a kind of molecular symbiotic association in which both partners benefit from the presence of each other's. Thus, protective effects provided by some of these MGEs may have generated an arm race between competing GVs in order to encode the most diverse arsenal of anti-viral weapons, explaining the unusual abundance of MGEs in GV genomes by a kind of ratchet effect.},
}
@article {pmid30109978,
year = {2018},
author = {Karmakar, K and Kundu, A and Rizvi, AZ and Dubois, E and Severac, D and Czernic, P and Cartieaux, F and DasGupta, M},
title = {Transcriptomic analysis with the progress of symbiosis in 'crack-entry' legume Arachis hypogaea highlights its contrast with 'infection thread' adapted legumes.},
journal = {Molecular plant-microbe interactions : MPMI},
volume = {},
number = {},
pages = {},
doi = {10.1094/MPMI-06-18-0174-R},
pmid = {30109978},
issn = {0894-0282},
abstract = {In root-nodule symbiosis, rhizobial invasion and nodule organogenesis is host controlled. In most legumes, rhizobia enter through infection-threads and nodule primordium in the cortex is induced from a distance. But in dalbergoid legumes like Arachis hypogaea, rhizobia directly invade cortical cells through epidermal cracks to generate the primordia. Herein we report the transcriptional dynamics with the progress of symbiosis in A. hypogaea at 1dpi: invasion; 4dpi: nodule primordia; 8dpi: spread of infection in nodule-like structure; 12dpi: immature nodules containing rod-shaped rhizobia; and 21dpi: mature nodules with spherical symbiosomes. Expression of putative orthologue of symbiotic genes in 'crack-entry' legume A. hypogaea was compared with infection thread adapted model legumes. The contrasting features were (i) higher expression of receptors like LYR3, EPR3 as compared to canonical NFRs (ii) late induction of transcription factors like NIN, NSP2 and constitutive high expression of ERF1, EIN2, bHLH476 and (iii) induction of divergent pathogenesis responsive PR-1 genes. Additionally, symbiotic orthologues of SymCRK, ROP6, RR9, SEN1 and DNF2 were not detectable and microsynteny analysis indicated the absence of RPG homologue in diploid parental genomes of A. hypogaea. The implications are discussed and a molecular framework that guide 'crack-entry' symbiosis in A. hypogaea is proposed.},
}
@article {pmid30109092,
year = {2018},
author = {Rubin, BER and Sanders, JG and Turner, KM and Pierce, NE and Kocher, SD},
title = {Social behaviour in bees influences the abundance of Sodalis (Enterobacteriaceae) symbionts.},
journal = {Royal Society open science},
volume = {5},
number = {7},
pages = {180369},
doi = {10.1098/rsos.180369},
pmid = {30109092},
issn = {2054-5703},
abstract = {Social interactions can facilitate transmission of microbes between individuals, reducing variation in gut communities within social groups. Thus, the evolution of social behaviours and symbiont community composition have the potential to be tightly linked. We explored this connection by characterizing the diversity of bacteria associated with both eusocial and solitary bee species within the behaviourally variable family Halictidae using 16S amplicon sequencing. Contrary to expectations, we found few differences in bacterial abundance or variation between social forms; most halictid species appear to share similar gut bacterial communities. However, several strains of Sodalis, a genus described as a symbiont in a variety of insects but yet to be characterized in bees, differ in abundance between eusocial and solitary bees. Phylogenetic reconstructions based on whole-genome alignments indicate that Sodalis has independently colonized halictids at least three times. These strains appear to be mutually exclusive within individual bees, although they are not host-species-specific and no signatures of vertical transmission were observed, suggesting that Sodalis strains compete for access to hosts. The symbiosis between halictids and Sodalis therefore appears to be in its early stages.},
}
@article {pmid30103505,
year = {2018},
author = {Rodríguez-Ruano, SM and Martín-Vivaldi, M and Peralta-Sánchez, JM and García-Martín, AB and Martínez-García, Á and Soler, JJ and Valdivia, E and Martínez-Bueno, M},
title = {Seasonal and Sexual Differences in the Microbiota of the Hoopoe Uropygial Secretion.},
journal = {Genes},
volume = {9},
number = {8},
pages = {},
doi = {10.3390/genes9080407},
pmid = {30103505},
issn = {2073-4425},
abstract = {The uropygial gland of hoopoe nestlings and nesting females hosts bacterial symbionts that cause changes in the characteristics of its secretion, including an increase of its antimicrobial activity. These changes occur only in nesting individuals during the breeding season, possibly associated with the high infection risk experienced during the stay in the hole-nests. However, the knowledge on hoopoes uropygial gland microbial community dynamics is quite limited and based so far on culture-dependent and molecular fingerprinting studies. In this work, we sampled wild and captive hoopoes of different sex, age, and reproductive status, and studied their microbiota using quantitative polymerase chain reaction (qPCR), fluorescence in situ hybridization (FISH) and pyrosequencing. Surprisingly, we found a complex bacterial community in all individuals (including non-nesting ones) during the breeding season. Nevertheless, dark secretions from nesting hoopoes harbored significantly higher bacterial density than white secretions from breeding males and both sexes in winter. We hypothesize that bacterial proliferation may be host-regulated in phases of high infection risk (i.e., nesting). We also highlight the importance of specific antimicrobial-producing bacteria present only in dark secretions that may be key in this defensive symbiosis. Finally, we discuss the possible role of environmental conditions in shaping the uropygial microbiota, based on differences found between wild and captive hoopoes.},
}
@article {pmid30102878,
year = {2018},
author = {Sharma, R and Janjani, L and Kulkarni, V and Patrikar, S and Singh, S},
title = {Therapeutic Efficacy of Cranioplasty After Decompressive Craniectomy for Traumatic Brain Injury: A Retrospective Study.},
journal = {Journal of oral and maxillofacial surgery : official journal of the American Association of Oral and Maxillofacial Surgeons},
volume = {},
number = {},
pages = {},
doi = {10.1016/j.joms.2018.07.007},
pmid = {30102878},
issn = {1531-5053},
abstract = {PURPOSE: Autologous bone removed at the time of decompressive craniectomy (DC) is always the first choice for cranioplasty. The aim of this study was to evaluate the therapeutic efficacy of cranioplasty after DC by measuring the changes in the Functional Independence Measure (FIM) score, as well as to draw a comparison with the pre-cranioplasty FIM score and to evaluate the differences in the outcomes of cases managed by 2 methods: autologous bone (group I) or titanium mesh (group II).<br><br>MATERIALS AND METHODS: We included 47 patients (36 male and 11 female patients) who underwent unilateral cranioplasty after DC for traumatic brain injury at our institute from 2008 to 2017 in this analytical single-institution retrospective study. The primary binary predictor variable was cranioplasty reconstructive material (autologous bone or mesh). The primary outcome variable of interest was increased, decreased, or unchanged FIM score. The secondary outcome variables included evaluation of immediate complications. The Mann-Whitney U test was used to evaluate differences between scores.<br><br>RESULTS: Group I (n = 26) underwent cranioplasty using autologous bone flap, whereas group II (n = 21) underwent cranioplasty using dynamic titanium mesh. Increases in FIM scores on the motor function subscale for group I (P = .01278) and group II (P = .00112) were statistically significant. Increases in FIM scores on the cognition subscale for group I (P = .17384) and group II (P = .9492) were statistically insignificant. Evaluation of the primary outcome variable (ie, increased, decreased, or unchanged FIM scores) and secondary outcome variables (ie, immediate complications) showed a statistically insignificant difference between the 2 groups with respect to improvement (P = .51).<br><br>CONCLUSIONS: This study showed that cranioplasty, irrespective of the reconstructive material, after DC in patients with traumatic brain injury results in a significant functional improvement apart from form and esthetics.},
}
@article {pmid30098586,
year = {2018},
author = {Torres, N and Antolín, MC and Garmendia, I and Goicoechea, N},
title = {Nutritional properties of Tempranillo grapevine leaves are affected by clonal diversity, mycorrhizal symbiosis and air temperature regime.},
journal = {Plant physiology and biochemistry : PPB},
volume = {130},
number = {},
pages = {542-554},
doi = {10.1016/j.plaphy.2018.08.004},
pmid = {30098586},
issn = {1873-2690},
mesh = {Antioxidants/metabolism ; Carotenoids/metabolism ; Chlorophyll/metabolism ; Coumaric Acids/metabolism ; Flavonols/metabolism ; Fluorometry ; Mycorrhizae/*metabolism ; *Nutritive Value ; Phenols/metabolism ; Plant Leaves/genetics/*metabolism ; *Symbiosis ; Temperature ; Vitis/genetics/*metabolism/microbiology ; },
abstract = {Tempranillo grapevine is widely cultivated in Spain and other countries over the world (Portugal, USA, France, Australia, and Argentina, among others) for its wine, but leaves are scarcely used for human or animal nutrition. Since high temperatures affect quality of fruits and leaves in grapevine and the association of Tempranillo with arbuscular mycorrhizal fungi (AMF) enhances the antioxidant properties of berries and leaves, we assessed the effect of elevated air temperature and mycorrhization, separately or combined, on the nutritional properties of Tempranillo leaves at the time of fruit harvest. Experimental assay included three clones (CL-260, CL-1048, and CL-1089) and two temperature regimes (24/14 °C or 28/18 °C day/night) during fruit ripening. Within each clone and temperature regime there were plants not inoculated or inoculated with AMF. The nutritional value of leaves increased under warming climate: elevated temperatures induced the accumulation of minerals, especially in CL-1089; antioxidant capacity and soluble sugars also increased in CL-1089; CL-260 showed enhanced amounts of pigments, and chlorophylls and soluble proteins increased in CL-1048. Results suggested the possibility of collecting leaves together with fruit harvest with different applications of every clone: those from CL-1089 would be adequate for an energetic diet and leaves from CL-260 and CL-1048 would be suitable for culinary processes. Mycorrhization improved the nutritional value of leaves by enhancing flavonols in all clones, hydroxycinnamic acids in CL-1089 and carotenoids in CL-260.},
}
@article {pmid30097019,
year = {2018},
author = {Dotson, BR and Soltan, D and Schmidt, J and Areskoug, M and Rabe, K and Swart, C and Widell, S and Rasmusson, AG},
title = {The antibiotic peptaibol alamethicin from Trichoderma permeabilises Arabidopsis root apical meristem and epidermis but is antagonised by cellulase-induced resistance to alamethicin.},
journal = {BMC plant biology},
volume = {18},
number = {1},
pages = {165},
doi = {10.1186/s12870-018-1370-x},
pmid = {30097019},
issn = {1471-2229},
support = {12:527//Carl Tryggers Stiftelse för Vetenskaplig Forskning/ ; 20150915//Crafoordska Stiftelsen/ ; 1283156424//Erasmus Mundus Action 2/ ; },
abstract = {BACKGROUND: Trichoderma fungi live in the soil rhizosphere and are beneficial for plant growth and pathogen resistance. Several species and strains are currently used worldwide in co-cultivation with crops as a biocontrol alternative to chemical pesticides even though little is known about the exact mechanisms of the beneficial interaction. We earlier found alamethicin, a peptide antibiotic secreted by Trichoderma, to efficiently permeabilise cultured tobacco cells. However, pre-treatment with Trichoderma cellulase made the cells resistant to subsequent alamethicin, suggesting a potential mechanism for plant tolerance to Trichoderma, needed for mutualistic symbiosis.<br><br>RESULTS: We here investigated intact sterile-grown Arabidopsis thaliana seedlings germinated in water or growth medium. These could be permeabilised by alamethicin but not if pretreated with cellulase. By following the fluorescence from the membrane-impermeable DNA-binding probe propidium iodide, we found alamethicin to mainly permeabilise root tips, especially the apical meristem and epidermis cells, but not the root cap and basal meristem cells nor cortex cells. Alamethicin permeabilisation and cellulase-induced resistance were confirmed by developing a quantitative in situ assay based on NADP-isocitrate dehydrogenase accessibility. The combined assays also showed that hyperosmotic treatment after the cellulase pretreatment abolished the induced cellulase resistance.<br><br>CONCLUSION: We here conclude the presence of cell-specific alamethicin permeabilisation, and cellulase-induced resistance to it, in root tip apical meristem and epidermis of the model organism A. thaliana. We suggest that contact between the plasma membrane and the cell wall is needed for the resistance to remain. Our results indicate a potential mode for the plant to avoid negative effects of alamethicin on plant growth and localises the point of potential damage and response. The results also open up for identification of plant genetic components essential for beneficial effects from Trichoderma on plants.},
}
@article {pmid30091610,
year = {2018},
author = {Zhang, L and Liu, JY and Gu, H and Du, Y and Zuo, JF and Zhang, Z and Zhang, M and Li, P and Dunwell, JM and Cao, Y and Zhang, Z and Zhang, YM},
title = {Bradyrhizobium diazoefficiens USDA 110- Glycine max Interactome Provides Candidate Proteins Associated with Symbiosis.},
journal = {Journal of proteome research},
volume = {17},
number = {9},
pages = {3061-3074},
doi = {10.1021/acs.jproteome.8b00209},
pmid = {30091610},
issn = {1535-3907},
abstract = {Although the legume-rhizobium symbiosis is a most-important biological process, there is a limited knowledge about the protein interaction network between host and symbiont. Using interolog- and domain-based approaches, we constructed an interspecies protein interactome containing 5115 protein-protein interactions between 2291 Glycine max and 290 Bradyrhizobium diazoefficiens USDA 110 proteins. The interactome was further validated by the expression pattern analysis in nodules, gene ontology term semantic similarity, co-expression analysis, and luciferase complementation image assay. In the G. max-B. diazoefficiens interactome, bacterial proteins are mainly ion channel and transporters of carbohydrates and cations, while G. max proteins are mainly involved in the processes of metabolism, signal transduction, and transport. We also identified the top 10 highly interacting proteins (hubs) for each species. Kyoto Encyclopedia of Genes and Genomes pathway analysis for each hub showed that a pair of 14-3-3 proteins (SGF14g and SGF14k) and 5 heat shock proteins in G. max are possibly involved in symbiosis, and 10 hubs in B. diazoefficiens may be important symbiotic effectors. Subnetwork analysis showed that 18 symbiosis-related soluble N-ethylmaleimide sensitive factor attachment protein receptor proteins may play roles in regulating bacterial ion channels, and SGF14g and SGF14k possibly regulate the rhizobium dicarboxylate transport protein DctA. The predicted interactome provide a valuable basis for understanding the molecular mechanism of nodulation in soybean.},
}
@article {pmid30088243,
year = {2018},
author = {Qin, L and Wei, D and Wang, Z and Alam, MA},
title = {Advantage Assessment of Mixed Culture of Chlorella vulgaris and Yarrowia lipolytica for Treatment of Liquid Digestate of Yeast Industry and Cogeneration of Biofuel Feedstock.},
journal = {Applied biochemistry and biotechnology},
volume = {},
number = {},
pages = {},
doi = {10.1007/s12010-018-2854-8},
pmid = {30088243},
issn = {1559-0291},
support = {21606230//the National Natural Science Foundation of China/ ; 201704030084//the Sciences and Technology of Guangzhou/ ; 2016A030312007//the Natural Science Foundation for research team of Guangdong Province/ ; 2015A020216003, 2016A010105001//the Science and Technology Program of Guangdong/ ; 2016YFB0601004//the National Key Research and Development Program-China/ ; },
abstract = {The symbiosis potential of microalgae and yeast is inherited with distinct advantages, providing an economical venue for their scale-up application. To assess the advantage of the mixed culture of microalgae Chlorella vulgaris and yeast Yarrowia lipolytica for treatment of liquid digestate of yeast industry (YILD) and cogeneration of biofuel feedstock, the cell growth characteristic, the nutrient removal efficiency, the energy storage potential of the mono, and mixed culture were investigated. The results indicated that the biomass concentration of the mixed culture (1.39-1.56 g/L of 5 times dilution group and 1.23-1.53 g/L of 10 times dilution group) was higher than those of mono cultures. The NH3-N and SO42- removal rates of the mixed culture were superior to mono cultures. Besides the higher lipid yield (0.073-0.154 g/L of 5 times dilution group and 0.112-0.183 g/L of 10 times dilution group), the higher yield of higher heating value (20.06-29.76 kJ/L of 5 times dilution group and 21.83-29.85 kJ/L of 10 times dilution group) was also obtained in the mixed culture. This study provides feasibility for remediation of YILD and cogeneration of biofuel feedstock using the mixed culture of microalgae and yeast.},
}
@article {pmid30087663,
year = {2018},
author = {Wongdee, J and Boonkerd, N and Teaumroong, N and Tittabutr, P and Giraud, E},
title = {Regulation of Nitrogen Fixation in Bradyrhizobium sp. Strain DOA9 Involves Two Distinct NifA Regulatory Proteins That Are Functionally Redundant During Symbiosis but Not During Free-Living Growth.},
journal = {Frontiers in microbiology},
volume = {9},
number = {},
pages = {1644},
doi = {10.3389/fmicb.2018.01644},
pmid = {30087663},
issn = {1664-302X},
abstract = {The Bradyrhizobium sp. DOA9 strain displays the unusual properties to have a symbiotic plasmid and to fix nitrogen during both free-living and symbiotic growth. Sequence genome analysis shows that this strain contains the structural genes of dinitrogenase (nifDK) and the nifA regulatory gene on both the plasmid and chromosome. It was previously shown that both nifDK clusters are differentially expressed depending on growth conditions, suggesting different mechanisms of regulation. In this study, we examined the functional regulatory role of the two nifA genes found on the plasmid (nifAp) and chromosome (nifAc) that encode proteins with a moderate level of identity (55%) and different structural architectures. Using gusA (β-glucuronidase) reporter strains, we showed that both nifA genes were expressed during both the free-living and symbiotic growth stages. During symbiosis with Aeschynomene americana, mutants in only one nifA gene were not altered in their symbiotic properties, while a double nifA mutant was drastically impaired in nitrogen fixation, indicating that the two NifA proteins are functionally redundant during this culture condition. In contrast, under in vitro conditions, the nifAc mutant was unable to fix nitrogen, and no effect of the nifAp mutation was detected, indicating that NifAc is essential to activate nif genes during free-living growth. In accordance, the nitrogenase fixation deficiency of this mutant could be restored by the introduction of nifAc but not by nifAp or by two chimeric nifA genes encoding hybrid proteins with the N-terminus part of NifAc and the C-terminus of NifAp. Furthermore, transcriptional analysis by RT-qPCR of the WT and two nifA mutant backgrounds showed that NifAc and NifAp activated the expression of both chromosome and plasmid structural nifDK genes during symbiosis, while only NifAc activated the expression of nifDKc during free-living conditions. In summary, this study provides a better overview of the complex mechanisms of regulation of the nitrogenase genes in the DOA9 strain that involve two distinct NifA proteins, which are exchangeable during symbiosis for the activation of nif genes but not during free-living growth where NifAc is essential for the activation of nifDKc.},
}
@article {pmid30087346,
year = {2018},
author = {Sugawara, M and Takahashi, S and Umehara, Y and Iwano, H and Tsurumaru, H and Odake, H and Suzuki, Y and Kondo, H and Konno, Y and Yamakawa, T and Sato, S and Mitsui, H and Minamisawa, K},
title = {Variation in bradyrhizobial NopP effector determines symbiotic incompatibility with Rj2-soybeans via effector-triggered immunity.},
journal = {Nature communications},
volume = {9},
number = {1},
pages = {3139},
doi = {10.1038/s41467-018-05663-x},
pmid = {30087346},
issn = {2041-1723},
support = {15K20868//Japan Society for the Promotion of Science (JSPS)/International ; 26252065//Japan Society for the Promotion of Science (JSPS)/International ; },
abstract = {Genotype-specific incompatibility in legume-rhizobium symbiosis has been suggested to be controlled by effector-triggered immunity underlying pathogenic host-bacteria interactions. However, the rhizobial determinant interacting with the host resistance protein (e.g., Rj2) and the molecular mechanism of symbiotic incompatibility remain unclear. Using natural mutants of Bradyrhizobium diazoefficiens USDA 122, we identified a type III-secretory protein NopP as the determinant of symbiotic incompatibility with Rj2-soybean. The analysis of nopP mutations and variants in a culture collection reveal that three amino acid residues (R60, R67, and H173) in NopP are required for Rj2-mediated incompatibility. Complementation of rj2-soybean by the Rj2 allele confers the incompatibility induced by USDA 122-type NopP. In response to incompatible strains, Rj2-soybean plants activate defense marker gene PR-2 and suppress infection thread number at 2 days after inoculation. These results suggest that Rj2-soybeans monitor the specific variants of NopP and reject bradyrhizobial infection via effector-triggered immunity mediated by Rj2 protein.},
}
@article {pmid30086814,
year = {2018},
author = {Yurchenko, V and Lukeš, J},
title = {Parasites and their (endo)symbiotic microbes.},
journal = {Parasitology},
volume = {145},
number = {10},
pages = {1261-1264},
doi = {10.1017/S0031182018001257},
pmid = {30086814},
issn = {1469-8161},
abstract = {Thanks to modern molecular biology methods, our understanding of the impact of (endo)symbiotic bacteria on parasitic protists and helminths is growing fast. In this issue, 9 papers have been brought together that describe various facets of the relationships between these microorganisms, reveal their range and high frequency, as well as their capacity to create novel biological complexity. Comparative analyses of these host-endosymbiont interactions indicate that there may be no discrete types of relationships but rather a continuum ranging from a dispensable endosymbiont minimally integrated within the host cell to organelles, such as mitochondria and plastids that evolved into an indispensable, deeply integrated components of the cell. We hope that this series of studies on parasites and (endo)symbiotic bacteria will increase awareness about these relationships and their representation in microbial ecology models.},
}
@article {pmid30086759,
year = {2018},
author = {Sharma, I and Singh, A and Siraj, F and Saxena, S},
title = {IL-8/CXCR1/2 signalling promotes tumor cell proliferation, invasion and vascular mimicry in glioblastoma.},
journal = {Journal of biomedical science},
volume = {25},
number = {1},
pages = {62},
doi = {10.1186/s12929-018-0464-y},
pmid = {30086759},
issn = {1423-0127},
mesh = {Apoptosis/genetics ; Cell Line, Tumor ; Cell Movement/genetics ; Cell Proliferation/genetics ; Disease Progression ; Female ; Gene Expression Regulation, Neoplastic ; Glioblastoma/*genetics/pathology ; Humans ; Interleukin-8/*genetics ; Male ; Neoplasm Invasiveness/genetics/pathology ; Neovascularization, Pathologic/*genetics/pathology ; Receptors, Interleukin-8A/*genetics ; Receptors, Interleukin-8B/*genetics ; Signal Transduction/genetics ; },
abstract = {BACKGROUND: Glioblastoma multiforme (GBM) is one of the lethal malignant tumors of the central nervous system. Despite advances made in understanding this complex disease, little has been achieved in improving clinical efficacy towards it. Factors such as chemokines play important role in shaping the tumor microenvironment which in turn plays a significant role in deciding course of tumor progression. In this study, we investigated the role of chemokine IL-8 in glioblastoma progression with particular emphasis on immunomodulation, cellular proliferation, invasion and vascular mimicry.<br><br>METHODS: Role of IL-8 in GBM immunology was determined by correlating the expression of IL-8 by immunohistochemistry with other immune cell markers such as CD3 and CD68. Effect of high IL-8 expression on overall survival, the difference in expression level between different GBM subgroups and anatomic structures were analyzed using other databases. Two GBM cell lines -U-87MG and LN-18 were used to study the impact of targeting IL-8-CXCR1/2 signalling using neutralizing antibodies and pharmacological antagonist. Reverse transcriptase-polymerase chain reaction and immunocytochemistry were used to determine the expression of these axes. Impact on cell viability and proliferation was assessed by MTT, proliferation marker-ki-67 and clonogenic survival assays. Multicellular tumor spheroids generated from GBM cell lines were used to study invasion in matrigel.<br><br>RESULTS: Weak Positive correlation was observed between IL-8 and CD3 as well as between IL-8 and CD68. High IL-8 expression in GBM patients was found to be associated with dismal survival. No significant difference in IL-8 expression between different molecular subgroups of GBM was observed. In vitro targeting of IL-8-CXCR1/2 signalling displayed a significant reduction in cell viability and proliferation, and spheroid invasion. Furthermore, the presence of CD34-/CXCR1+ vessels in GBM tissues showed the involvement of IL-8/CXCR1 in vascular mimicry structure formation.<br><br>CONCLUSION: These results suggest a direct involvement of IL-8-CXCR1/2 axes in GBM progression by promoting both cell proliferation and invasion and indirectly by promoting neovascularization in the form of vascular mimicry.},
}
@article {pmid30084172,
year = {2019},
author = {Wendlandt, CE and Regus, JU and Gano-Cohen, KA and Hollowell, AC and Quides, KW and Lyu, JY and Adinata, ES and Sachs, JL},
title = {Host investment into symbiosis varies among genotypes of the legume Acmispon strigosus, but host sanctions are uniform.},
journal = {The New phytologist},
volume = {221},
number = {1},
pages = {446-458},
doi = {10.1111/nph.15378},
pmid = {30084172},
issn = {1469-8137},
support = {1150278//NSF DEB/ ; },
abstract = {Efficient host control predicts the extirpation of ineffective symbionts, but they are nonetheless widespread in nature. We tested three hypotheses for the maintenance of symbiotic variation in rhizobia that associate with a native legume: partner mismatch between host and symbiont, such that symbiont effectiveness varies with host genotype; resource satiation, whereby extrinsic sources of nutrients relax host control; and variation in host control among host genotypes. We inoculated Acmispon strigosus from six populations with three Bradyrhizobium strains that vary in symbiotic effectiveness on sympatric hosts. We measured proxies of host and symbiont fitness in single- and co-inoculations under fertilization treatments of zero added nitrogen (N) and near-growth-saturating N. We examined two components of host control: 'host investment' into nodule size during single- and co-inoculations, and 'host sanctions' against less effective strains during co-inoculations. The Bradyrhizobium strains displayed conserved growth effects on hosts, and host control did not decline under experimental fertilization. Host sanctions were robust in all hosts, but host lines from different populations varied significantly in measures of host investment in both single- and co-inoculation experiments. Variation in host investment could promote variation in symbiotic effectiveness and prevent the extinction of ineffective Bradyrhizobium from natural populations.},
}
@article {pmid30083666,
year = {2018},
author = {Borfecchia, E and Beato, P and Svelle, S and Olsbye, U and Lamberti, C and Bordiga, S},
title = {Cu-CHA - a model system for applied selective redox catalysis.},
journal = {Chemical Society reviews},
volume = {47},
number = {22},
pages = {8097-8133},
doi = {10.1039/c8cs00373d},
pmid = {30083666},
issn = {1460-4744},
abstract = {We review the structural chemistry and reactivity of copper-exchanged molecular sieves with chabazite (CHA) topology, as an industrially applied catalyst in ammonia mediated reduction of harmful nitrogen oxides (NH3-SCR) and as a general model system for red-ox active materials (also the recent results in the direct conversion of methane to methanol are considered). Notwithstanding the apparent structural simplicity of the material, a crystalline zeolite with only one crystallographically independent T site, the Cu-SSZ-13 catalyst reveals a high degree of complexity that has been decrypted by state of the art characterization tools. From the reviewed data, the following important aspects in the understanding of the Cu-SSZ-13 catalyst clearly emerged: (i) the structural dynamics of the Cu-species require precise control of the environmental conditions during activation and characterization; (ii) the availability of a large library of well-defined catalysts with different Si/Al and Cu/Al compositional ratios is key in unravelling the red-ox properties of the active Cu sites; (iii) a multi-technique approach is required, combining complementary techniques able to provide independent structural, electronic and vibrational information; (iv) synchrotron radiation based techniques (EXAFS, XANES, XES and time-resolved powder XRD) played a relevant role; (v) operando methodology (possibly supported by advanced chemometric approaches) is essential in obtaining structure-reactivity relations; (vi) the support of theoretical studies has been indispensable for the interpretation of the experimental output from characterization and for a critical assessment of mechanistic models. The old literature that classified Cu-exchanged zeolites in the category of single-site catalysts has been partially disproved by the recent advanced studies where it has been shown that the active site in the low temperature NH3-SCR catalyst is a mobile Cu-molecular entity that &quot;lives in symbiosis&quot; with an inorganic solid framework. Only in the high temperature NH3-SCR regime do the mobile Cu-species lose their ligands and find docking sites at the internal walls of the zeolite framework, thus reflecting the idea of a single-site catalyst. After a brief introduction, the review is divided into three main parts devoted to characterization (Section 2), reactivity (Section 3), and industrial applications (Section 4), followed by some concluding remarks and providing a perspective of the field.},
}
@article {pmid30082826,
year = {2018},
author = {Moriizumi, Y and Tabata, KV and Watanabe, R and Doura, T and Kamiya, M and Urano, Y and Noji, H},
title = {Hybrid cell reactor system from Escherichia coli protoplast cells and arrayed lipid bilayer chamber device.},
journal = {Scientific reports},
volume = {8},
number = {1},
pages = {11757},
doi = {10.1038/s41598-018-30231-0},
pmid = {30082826},
issn = {2045-2322},
abstract = {We developed a novel hybrid cell reactor system via functional fusion of single Escherichia coli protoplast cells, that are deficient in cell wall and expose plasma membrane, with arrayed lipid bilayer chambers on a device in order to incorporate the full set of cytosolic and membrane constituents into the artificial chambers. We investigated gene expression activity to represent the viability of the hybrid cell reactors: over 20% of hybrid cells showed gene expression activity from plasmid or mRNA. This suggests that the hybrid cell reactors retained fundamental activity of genetic information transduction. To expand the applicability of the hybrid cell reactors, we also developed the E. coli-in-E. coli cytoplasm system as an artificial parasitism system. Over 30% of encapsulated E. coli cells exhibited normal cell division, showing that hybrid cells can accommodate and cultivate living cells. This novel artificial cell reactor technology would enable unique approaches for synthetic cell researches such as reconstruction of living cell, artificial parasitism/symbiosis system, or physical simulation to test functionality of synthetic genome.},
}
@article {pmid30082253,
year = {2018},
author = {Li, H and Li, S and Srinivasakannan, C and Zhang, L and Yin, S and Yang, K and Xie, H},
title = {Efficient cleaning extraction of silver from spent symbiosis lead-zinc mine assisted by ultrasound in sodium thiosulfate system.},
journal = {Ultrasonics sonochemistry},
volume = {49},
number = {},
pages = {118-127},
doi = {10.1016/j.ultsonch.2018.07.034},
pmid = {30082253},
issn = {1873-2828},
abstract = {The process to fast recovery of silver from the spent symbiosis lead-zinc mine enhanced by ultrasound has been developed. A system composed of thiosulfate and the spent symbiosis lead-zinc mine under ultrasound radiation is researched and compared with regular methods to prove the superiority of ultrasound enhanced leaching. Oxygen is not provided by the usual way but by the cavitation of ultrasound, and the effect of ultrasonic enhanced leaching is more obvious than oxygen enhanced leaching effect. We are more authoritative by combining some valuable literature after conducting systematic experiments. The process mechanism was analyzed by fire assaying, XRD, XRF, SEM and EDS. The optimal conditions were found out through single factor experiments: stirring rate of 300 rpm, thiosulfate concentration of 75 g/L, leaching temperature of 303 K, PH of 5, leaching time of 2 h and the ultrasound power of 100 W. And the leaching rate is 77.34% under the best conditions. When the ultrasonic experiment has the same parameters as the normal, the leaching rate at five minutes under ultrasonic conditions was 73.88%, while the leaching rate was only 72.51% at two hours under normal conditions. The apparent activation energy under conventional and ultrasonic conditions is 12.47 kJ/mol and 12.35 kJ/mol, respectively, and it is proved that both are controlled by diffusion.},
}
@article {pmid30080626,
year = {2018},
author = {Torres, N and Goicoechea, N and Zamarreño, AM and Carmen Antolín, M},
title = {Mycorrhizal symbiosis affects ABA metabolism during berry ripening in Vitis vinifera L. cv. Tempranillo grown under climate change scenarios.},
journal = {Plant science : an international journal of experimental plant biology},
volume = {274},
number = {},
pages = {383-393},
doi = {10.1016/j.plantsci.2018.06.009},
pmid = {30080626},
issn = {1873-2259},
mesh = {Abscisic Acid/*metabolism ; Anthocyanins/*metabolism ; Climate Change ; Mycorrhizae/*physiology ; Phenols/*metabolism ; Plant Growth Regulators/*metabolism ; Symbiosis ; Temperature ; Vitis/*microbiology/physiology ; Water/physiology ; },
abstract = {Arbuscular mycorrhizal symbiosis is a promising tool for improving the quality of grapes under changing environments. Therefore, the aim of this research was to determine if the ability of arbuscular mycorrhizal fungi (AMF) to enhance phenolic content (specifically, anthocyanins) in a climate change framework could be mediated by alterations in berry ABA metabolism during ripening. The study was carried out on fruit-bearing cuttings of cv. Tempranillo (CL-1048 and CL-1089) inoculated (+M) or not (-M) with AMF. Two experimental designs were implemented. In the first experiment +M and -M plants were subjected to two temperatures (24/14 °C or 28/18 °C (day/night)) from fruit set to berry maturity. In the second experiment, +M and -M plants were subjected to two temperatures (24/14 °C or 28/18 °C (day/night)) combined with two irrigation regimes (late water deficit (LD) and full irrigation (FI)). At 28/18 °C AMF contributed to an increase in berry anthocyanins and modulated ABA metabolism, leading to higher ABA-GE and 7'OH-ABA and lower phaseic acid (PA) in berries compared to -M plants. Under the most stressful scenario (LD and 28/18 °C), at harvest +M plants exhibited higher berry anthocyanins and 7´OH-ABA and lower PA and dihydrophaseic acid (DPA) levels than -M plants. These findings highlight the involvement of ABA metabolism into the ability of AMF to improve some traits involved in the quality of grapes under global warming scenarios.},
}
@article {pmid30077583,
year = {2018},
author = {Guo, Y and Matsuoka, Y and Miura, T and Nishizawa, T and Ohta, H and Narisawa, K},
title = {Complete genome sequence of Agrobacterium pusense VsBac-Y9, a bacterial symbiont of the dark septate endophytic fungus Veronaeopsis simplex Y34 with potential for improving fungal colonization in roots.},
journal = {Journal of biotechnology},
volume = {284},
number = {},
pages = {31-36},
doi = {10.1016/j.jbiotec.2018.07.045},
pmid = {30077583},
issn = {1873-4863},
mesh = {Agrobacterium/*genetics/physiology ; Ascomycota/*physiology ; Base Sequence ; DNA, Bacterial/genetics ; *Genome, Bacterial ; Lycopersicon esculentum/*microbiology ; Plant Roots/*microbiology ; Symbiosis ; },
abstract = {A Rhizobium-related bacterium (Rhizobium sp. VsBac-Y9) is a symbiont living with the dark septate endophytic (DSE) fungus Veronaeopsis simplex Y34. Co-inoculation of Rhizobium sp. VsBac-Y9 with V. simplex Y34 improves the fungal colonization of tomato roots, resulting in a significant increase in aboveground biomass. This study sequenced the complete genome of this V. simplex-helper bacterium using the PacBio and Illumina MiSeq platforms. Hybrid assembly using SPAdes outputted a circular chromosome, a linear chromid, and a circular plasmid for a total genome 5,321,211 bp in size with a G + C content of 59.2%. Analysis of concatenated housekeeping genes (atpD-dnaK-groEL-lepA-recA-rpoB-thrE) and calculation of average nucleotide identity, showed that VsBac-Y9 was affiliated with the species Agrobacterium pusense (syn. Rhizobium pusense). Genome analysis revealed that A. pusense VsBac-Y9 contains a series of genes responsible for the host interactions with both fungus and plant. Such genomic information will provide new insights into developing co-inoculants of endophytic fungus and its symbiotic bacterium in future agricultural innovation.},
}
@article {pmid30071473,
year = {2018},
author = {Parniske, M},
title = {Uptake of bacteria into living plant cells, the unifying and distinct feature of the nitrogen-fixing root nodule symbiosis.},
journal = {Current opinion in plant biology},
volume = {44},
number = {},
pages = {164-174},
doi = {10.1016/j.pbi.2018.05.016},
pmid = {30071473},
issn = {1879-0356},
abstract = {Despite the presence of complex microbiota on the surfaces of all plants, the uptake of bacteria into plant cells and the subsequent accommodation in a membrane-enclosed compartment is restricted to the nitrogen-fixing root nodule and the Gunnera-Nostoc symbiosis. The plant cell wall and the outward-directed turgor pressure are major constraints for bacterial uptake because localised lysis of the cell wall endangers the integrity of the protoplast. Host cell integrity is consistently maintained by turgescent neighbours, connected via apoplastic polymers that seal a bacteria-containing extracellular compartment prior to localized cell wall lysis. Its unifying and almost exclusive phylogenetic distribution pinpoints the ability to take up bacteria into living plant cells as a key step during the evolution of the nitrogen-fixing root nodule symbiosis.},
}
@article {pmid30070651,
year = {2018},
author = {Alabid, I and Glaeser, SP and Kogel, KH},
title = {Endofungal Bacteria Increase Fitness of their Host Fungi and Impact their Association with Crop Plants.},
journal = {Current issues in molecular biology},
volume = {30},
number = {},
pages = {59-74},
doi = {10.21775/cimb.030.059},
pmid = {30070651},
issn = {1467-3045},
abstract = {Endofungal bacteria are bacterial symbionts of fungi that exist within fungal hyphae and spores. There is increasing evidence that these bacteria, alone or in combination with their fungal hosts play a critical role in tripartite symbioses with plants, where they may contribute to plant growth and disease resistance to microbial pathogens. As the frequency of bacteria in fungi is commonly very low, breakthroughs in technology such as molecular taxonomy and laser scanning microscopy were required to establish the functional contribution of these bacteria in complex symbioses. Yet, the overall biological significance of endofungal bacteria is largely unknown and further progress in understanding is hampered by a very few biological systems where endofungal bacteria have been described mechanistically. We review here the current knowledge on endobacteria (EB) and their role in different types of fungal symbioses with plants. We show that various attempts to cure fungal cells from endobacteria failed, further suggesting that they play a crucial role in the symbiosis. Moreover, isolation of some of the endobacteria from their fungal hosts allowed confirming their autonomous beneficial activity such as plant growth promotion and resistance-inducing activity. The review addresses the potential agricultural significance of endofungal bacteria and their role in supporting sustainable agriculture by promoting plant growth, improving plant resistance, and decreasing yield loss caused by many microbial pathogens.},
}
@article {pmid30069723,
year = {2018},
author = {Gueddou, A and Swanson, E and Hezbri, K and Nouioui, I and Ktari, A and Simpson, S and Morris, K and Kelley Thomas, W and Ghodhbane-Gtari, F and Gtari, M and Tisa, LS},
title = {Draft genome sequence of the symbiotic Frankia sp. strain BMG5.30 isolated from root nodules of Coriaria myrtifolia in Tunisia.},
journal = {Antonie van Leeuwenhoek},
volume = {},
number = {},
pages = {},
doi = {10.1007/s10482-018-1138-1},
pmid = {30069723},
issn = {1572-9699},
support = {022821//USDA National Institute of Food and Agriculture Hatch 022821/ ; 2015-67014-22849//National Institute of Food and Agriculture/ ; DBI-1229361//Directorate for Biological Sciences/ ; },
abstract = {Frankia sp. strain BMG5.30 was isolated from root nodules of a Coriaria myrtifolia seedling on soil collected in Tunisia and represents the second cluster 2 isolate. Frankia sp. strain BMG5.30 was able to re-infect C. myrtifolia generating root nodules. Here, we report its 5.8-Mbp draft genome sequence with a G + C content of 70.03% and 4509 candidate protein-encoding genes.},
}
@article {pmid30066414,
year = {2018},
author = {Singh, P and Patil, Y and Rale, V},
title = {Biosurfactant production: emerging trends and promising strategies.},
journal = {Journal of applied microbiology},
volume = {},
number = {},
pages = {},
doi = {10.1111/jam.14057},
pmid = {30066414},
issn = {1365-2672},
abstract = {Biosurfactants are economically most sought after biotechnological compounds of the 21st century. However, inefficient bioprocessing has mitigated the economical commercial production of these compounds. Although much work is being done on the use of low-cost substrates for their production, a paucity of literature exists on the upcoming bioprocess optimization strategies and their successes and potential for economical biosurfactant production. This review discusses some of the latest developments and most promising strategies to enhance and economize the biosurfactant production process. Recent market analysis, developments in the field of optimally formulated cost credit substrates for enhanced product formation and subsequent process economization are few of the critical aspects highlighted here. Use of nanoparticles and coproduction of biosurfactant along with other commercially important compounds like enzymes, are other upcoming bioprocess intensification strategies. The recent developments discussed here would not only give an overview of pertinent parameters for economic biosurfactant production but would also bring to fore multiple strategies that would open up new avenues of research on biosurfactant production. This would go a long way in making biosurfactants a commercially successful compound of the current century.},
}
@article {pmid30066215,
year = {2018},
author = {Stencel, A and Wloch-Salamon, DM},
title = {Some theoretical insights into the hologenome theory of evolution and the role of microbes in speciation.},
journal = {Theory in biosciences = Theorie in den Biowissenschaften},
volume = {137},
number = {2},
pages = {197-206},
doi = {10.1007/s12064-018-0268-3},
pmid = {30066215},
issn = {1611-7530},
support = {2018/28/T/HS1/00201//Narodowe Centrum Nauki/ ; Opus 2017/25/B/NZ8/01035//Narodowe Centrum Nauki/ ; DS/762 - K/ZDS/007338//Uniwersytet Jagielloński w Krakowie/ ; },
abstract = {Research on symbiotic communities (microbiomes) of multicellular organisms seems to be changing our understanding of how species of plants and animals have evolved over millions of years. The quintessence of these discoveries is the emergence of the hologenome theory of evolution, founded on the concept that a holobiont (a host along with all of its associated symbiotic microorganisms) acts a single unit of selection in the process of evolution. Although the hologenome theory has become very popular among certain scientific circles, its principles are still being debated. In this paper, we argue, firstly, that only a very small number of symbiotic microorganisms are sufficiently integrated into multicellular organisms to act in concert with them as units of selection, thus rendering claims that holobionts are units of selection invalid. Secondly, even though holobionts are not units of selection, they can still constitute genuine units from an evolutionary perspective, provided we accept certain constraints: mainly, they should be considered units of co-operation. Thirdly, we propose a reconciliation of the role of symbiotic microorganisms with the theory of speciation through the use of a developed framework. Mainly, we will argue that, in order to understand the role of microorganisms in the speciation of multicellular organisms, it is not necessary to consider holobionts units of selection; it is sufficient to consider them units of co-operation.},
}
@article {pmid30065740,
year = {2018},
author = {Kereszt, A and Mergaert, P and Montiel, J and Endre, G and Kondorosi, É},
title = {Impact of Plant Peptides on Symbiotic Nodule Development and Functioning.},
journal = {Frontiers in plant science},
volume = {9},
number = {},
pages = {1026},
doi = {10.3389/fpls.2018.01026},
pmid = {30065740},
issn = {1664-462X},
abstract = {Ribosomally synthesized peptides have wide ranges of functions in plants being, for example, signal molecules, transporters, alkaloids, or antimicrobial agents. Legumes are an unprecedented rich source of peptides, which are used to control the symbiosis of these plants with the nitrogen-fixing Rhizobium bacteria. Here, we discuss the function and the evolution of these peptides playing an important role in the formation or functioning of the symbiotic organs, the root nodules. We distinguish peptides that can be either cell-autonomous or secreted short-range or long-range signals, carrying messages in or between plant cells or that can act as effectors interacting with the symbiotic bacteria. Peptides are further classified according to the stage of the symbiotic process where they act. Several peptide classes, including RALF, DLV, ENOD40, and others, control Rhizobium infection and the initiation of cell divisions and the formation of nodule primordia. CLE and CEP peptides are implicated in systemic and local control of nodule initiation during autoregulation of nodulation and in response to the nutritional demands of the plant. Still other peptides act at later stages of the symbiosis. The PSK peptide is thought to be involved in the suppression of immunity in nodules and the nodule-specific cysteine-rich, GRP, and SNARP (LEED..PEED) peptide families are essential in the functioning of the nitrogen fixing root nodules. The NCRs and possibly also the GRP and SNARPs are targeted to the endosymbionts and play essential roles in the terminal differentiation of these bacteria.},
}
@article {pmid30065035,
year = {2018},
author = {Armstrong, EJ and Roa, JN and Stillman, JH and Tresguerres, M},
title = {Symbiont photosynthesis in giant clams is promoted by V-type H+-ATPase from host cells.},
journal = {The Journal of experimental biology},
volume = {221},
number = {Pt 18},
pages = {},
doi = {10.1242/jeb.177220},
pmid = {30065035},
issn = {1477-9145},
abstract = {Giant clams (genus Tridacna) are the largest living bivalves and, like reef-building corals, host symbiotic dinoflagellate algae (Symbiodinium) that significantly contribute to their energy budget. In turn, Symbiodinium rely on the host to supply inorganic carbon (Ci) for photosynthesis. In corals, host 'proton pump' vacuolar-type H+-ATPase (VHA) is part of a carbon-concentrating mechanism (CCM) that promotes Symbiodinium photosynthesis. Here, we report that VHA in the small giant clam (Tridacna maxima) similarly promotes Symbiodinium photosynthesis. VHA was abundantly expressed in the apical membrane of epithelial cells of T. maxima's siphonal mantle tubule system, which harbors Symbiodinium Furthermore, application of the highly specific pharmacological VHA inhibitors bafilomycin A1 and concanamycin A significantly reduced photosynthetic O2 production by ∼40%. Together with our observation that exposure to light increased holobiont aerobic metabolism ∼5-fold, and earlier estimates that translocated fixed carbon exceeds metabolic demand, we conclude that VHA activity in the siphonal mantle confers strong energetic benefits to the host clam through increased supply of Ci to algal symbionts and subsequent photosynthetic activity. The convergent role of VHA in promoting Symbiodinium photosynthesis in the giant clam siphonal mantle tubule system and coral symbiosome suggests that VHA-driven CCM is a common exaptation in marine photosymbioses that deserves further investigation in other taxa.},
}
@article {pmid30059001,
year = {2018},
author = {Normand, P and Nouioui, I and Pujic, P and Fournier, P and Dubost, A and Schwob, G and Klenk, HP and Nguyen, A and Abrouk, D and Herrera-Belaroussi, A and Pothier, JF and Pflüger, V and Fernandez, MP},
title = {Frankia canadensis sp. nov., isolated from root nodules of Alnus incana subspecies rugosa.},
journal = {International journal of systematic and evolutionary microbiology},
volume = {68},
number = {9},
pages = {3001-3011},
doi = {10.1099/ijsem.0.002939},
pmid = {30059001},
issn = {1466-5034},
mesh = {Alnus/*microbiology ; Bacterial Typing Techniques ; Base Composition ; DNA, Bacterial/genetics ; Fatty Acids/chemistry ; Frankia/*classification/genetics/isolation &amp; purification ; Nucleic Acid Hybridization ; Phospholipids/chemistry ; *Phylogeny ; Plant Roots/*microbiology ; Quebec ; RNA, Ribosomal, 16S/genetics ; Sequence Analysis, DNA ; Vitamin K 2/analogs &amp; derivatives/chemistry ; },
abstract = {Strain ARgP5T, an actinobacterium isolated from a root nodule present on an Alnus incana subspecies rugosa shrub growing in Quebec City, Canada, was the subject of polyphasic taxonomic studies to clarify its status within the genus Frankia. 16S rRNA gene sequence similarities and ANI values between ARgP5T and type strains of species of the genus Frankiawith validly published names were 98.8 and 82 % or less, respectively. The in silico DNA G+C content was 72.4 mol%. ARgP5T is characterised by the presence of meso-A2pm, galactose, glucose, mannose, rhamnose (trace), ribose and xylose as whole-organism hydrolysates; MK-9(H8) as predominant menaquinone; diphosphatidylglycerol, phosphatidylinositol and phosphatidylglycerol as polar lipids and iso-C16 : 0 and C17 : 1ω8c as major fatty acids. The proteomic results confirmed the distinct position of ARgP5T from its closest neighbours in Frankiacluster 1. ARgP5T was found to be infective on two alder (Alnus glutinosa and Alnusalnobetula subsp. crispa) and on one bayberry (Morella pensylvanica) species and to fix nitrogen in symbiosis and in pure culture. On the basis of phylogenetic (16S rRNA gene sequence), genomic, proteomic and phenotypic results, strain ARgP5T (=DSM 45898=CECT 9033) is considered to represent a novel species within the genus Frankia for which the name Frankia canadensis sp. nov., is proposed.},
}
@article {pmid30057302,
year = {2018},
author = {Berg, M and Koskella, B},
title = {Nutrient- and Dose-Dependent Microbiome-Mediated Protection against a Plant Pathogen.},
journal = {Current biology : CB},
volume = {28},
number = {15},
pages = {2487-2492.e3},
doi = {10.1016/j.cub.2018.05.085},
pmid = {30057302},
issn = {1879-0445},
abstract = {Plant-associated microbial communities can promote plant nutrient uptake, growth, and resistance to pathogens [1-3]. Host resistance to infection can increase directly through commensal-pathogen interactions or indirectly through modulation of host defenses [4-6], the mechanisms of which are best described for rhizosphere-associated bacteria. For example, Arabidopsis plants infected with the foliar pathogen, Pseudomonas syringae pathovar tomato (Pst), increase their root secretion of malate, which attracts Bacillus subtillis to the roots and leads to a stronger host response against Pst [7]. Although there are numerous examples of individual defensive symbionts (e.g., [8]), it is less clear whether this type of protection is an emergent property of whole microbial communities. In particular, relatively little is known about whether and how the presence of phyllosphere (above-ground) microbial communities can increase host resistance against pathogens. In this study, we examined the ability of augmented tomato phyllosphere microbiomes to confer resistance against the causal agent of bacterial speck, Pst. Across five independent experiments, the augmented phyllosphere microbiome was found to decrease pathogen colonization. Furthermore, the dose of commensal bacteria applied affected the degree of protection conferred, and although the effect is dependent on microbial composition, it is not clearly related to overall bacterial diversity. Finally, our results suggest that resources available to the phyllosphere microbial community may play an important role in protection, as the addition of fertilizer abolished the observed microbiome-mediated protection. Together, these results have clear relevance to microbiome-mediated protection within agricultural settings and the use of plant probiotics to increase disease resistance.},
}
@article {pmid30056833,
year = {2018},
author = {Mercer, F and Johnson, PJ},
title = {Trichomonas vaginalis: Pathogenesis, Symbiont Interactions, and Host Cell Immune Responses.},
journal = {Trends in parasitology},
volume = {34},
number = {8},
pages = {683-693},
doi = {10.1016/j.pt.2018.05.006},
pmid = {30056833},
issn = {1471-5007},
mesh = {Humans ; Immunity, Cellular/*immunology ; *Symbiosis ; Trichomonas Infections/*immunology/*pathology ; Trichomonas vaginalis/*immunology ; },
abstract = {The parasite Trichomonas vaginalis (Tv) causes a highly prevalent sexually transmitted infection. As an extracellular pathogen, the parasite mediates adherence to epithelial cells to colonize the human host. In addition, the parasite interfaces with the host immune system and the vaginal microbiota. Modes of Tv pathogenesis include damage to host tissue mediated by parasite killing of host cells, disruption of steady-state vaginal microbial ecology, and eliciting inflammation by activating the host immune response. Recent Tv research has uncovered new players that contribute to multifactorial mechanisms of host-parasite adherence and killing, and has examined the relationship between Tv and vaginal bacteria. Mechanisms that may lead to parasite recognition and killing, or the evasion of host immune cells, have also been revealed.},
}
@article {pmid30055345,
year = {2018},
author = {Hu, LY and Li, D and Sun, K and Cao, W and Fu, WQ and Zhang, W and Dai, CC},
title = {Mutualistic fungus Phomopsis liquidambari increases root aerenchyma formation through auxin-mediated ethylene accumulation in rice (Oryza sativa L.).},
journal = {Plant physiology and biochemistry : PPB},
volume = {130},
number = {},
pages = {367-376},
doi = {10.1016/j.plaphy.2018.07.018},
pmid = {30055345},
issn = {1873-2690},
mesh = {Ascomycota/*metabolism/physiology ; Endophytes/metabolism/physiology ; Ethylenes/*metabolism ; Indoleacetic Acids/*metabolism ; Microscopy, Electron, Scanning ; Oryza/growth &amp; development/metabolism/*microbiology/ultrastructure ; Plant Growth Regulators/*metabolism ; Plant Roots/growth &amp; development/metabolism/*microbiology/ultrastructure ; Real-Time Polymerase Chain Reaction ; *Symbiosis ; },
abstract = {The fungal endophyte Phomopsis liquidambari can improve nitrification rates and alter the abundance and composition of ammonia-oxidizers in the soil rhizosphere of rice. Aerenchyma is related to oxygen transport efficiency and contributes to the enhanced rhizospheric nitrification under flooding conditions. However, whether and how P. liquidambari affects aerenchyma formation is largely unknown. We therefore conducted pot and hydroponic experiments to investigate the changes of aerenchyma area, ethylene and indole-3-acetic acid (IAA) levels in rice with or without P. liquidambari infection. Our results showed that the larger aerenchyma area in rice roots with P. liquidambari inoculation was associated with markedly up-regulated expression of genes related to aerenchyma formation. Meanwhile, P. liquidambari inoculation substantially elevated root porosity (POR) and radial oxygen loss (ROL), leading to the enhancement of oxidation-reduction potential (ORP) under pot condition. Besides, P. liquidambari significantly increased IAA and ethylene levels in rice by stimulating the expression of genes involved in auxin and ethylene biosyntheses. Furthermore, auxin that partly acting upstream of ethylene signalling played an essential role in P. liquidambari-promoted aerenchyma formation. These results verified the direct contribution of P. liquidambari in promoting aerenchyma formation via the accumulation of IAA and ethylene in rice roots, which provides a constructive suggestion for improving hypoxia tolerance through plant-endophyte interactions.},
}
@article {pmid30053907,
year = {2018},
author = {Cheng, C and Wickham, JD and Chen, L and Xu, D and Lu, M and Sun, J},
title = {Bacterial microbiota protect an invasive bark beetle from a pine defensive compound.},
journal = {Microbiome},
volume = {6},
number = {1},
pages = {132},
doi = {10.1186/s40168-018-0518-0},
pmid = {30053907},
issn = {2049-2618},
support = {QYZDJ-SSW-SMC024//Frontier Science Key Project of the Chinese Academy of Sciences/ ; 31110103903, 31222013, and 31702018//National Natural Science Foundation of China/ ; XDB11050000//Strategic Priority Research Program of the Chinese Academy of Sciences/ ; },
abstract = {BACKGROUND: There is growing evidence that some devastating biotic invasions are facilitated by microbial symbionts. The red turpentine beetle (RTB), an innocuous secondary insect attacking weakened trees in North America, has formed an invasive complex with the fungus Leptographium procerum in China, and this invasive beetle-fungus symbiotic complex is capable of attacking and killing healthy pines. A previous study demonstrated that three Chinese-resident fungi, newly acquired by RTB in China, induce high levels of a phenolic defensive chemical, naringenin, in pines and this invasive beetle-fungus complex is suppressed by elevated levels of naringenin while the beetle uses its gallery as an external detoxification system in which particular yeast-like fungi and bacterial species biodegrade naringenin. However, the functional roles of key microbial players in the symbiosis, contained within the microbiome of the bark beetle gallery, have not been well elucidated.<br><br>RESULTS: In this report, the symbiotic naringenin-degrading microbiota were found to increase RTB survivorship in the presence of induced host defenses, and potential genes associated with degradation pathways were discovered. While fungi in the gallery microbiota had little involvement in naringenin degradation, bacterial community structure within the beetle gallery was highly correlated to naringenin degrading activity. Phylotypes of the Gram-negative bacterial genus Novosphingobium, which possessed genes involved in degradation pathways, were highly correlated to naringenin degradation activities and RTB associated with an isolated species of this genus acquired protection against naringenin and gained fitness.<br><br>CONCLUSIONS: Our results demonstrated that symbiotic bacterial community of RTB galleries enhances the survivorship and overall fitness of invasive beetles by degrading the host phenolic naringenin, ultimately overcoming the tree defenses and facilitating the success of the invasive beetle-fungi complex. This dynamic interplay between the invasive insect pest and multipartite microbes suggests a putative mechanism in invasion ecology for mitigating biotic resistance to symbiotic invasion.},
}
@article {pmid30051940,
year = {2018},
author = {Averill, C and Dietze, MC and Bhatnagar, JM},
title = {Continental-scale nitrogen pollution is shifting forest mycorrhizal associations and soil carbon stocks.},
journal = {Global change biology},
volume = {24},
number = {10},
pages = {4544-4553},
doi = {10.1111/gcb.14368},
pmid = {30051940},
issn = {1365-2486},
support = {//National Oceanic and Atmospheric Administration/International ; 1638577//National Science Foundation/International ; //Peter Paul Professorship/International ; },
abstract = {Most tree roots on Earth form a symbiosis with either ecto- or arbuscular mycorrhizal fungi. Nitrogen fertilization is hypothesized to favor arbuscular mycorrhizal tree species at the expense of ectomycorrhizal species due to differences in fungal nitrogen acquisition strategies, and this may alter soil carbon balance, as differences in forest mycorrhizal associations are linked to differences in soil carbon pools. Combining nitrogen deposition data with continental-scale US forest data, we show that nitrogen pollution is spatially associated with a decline in ectomycorrhizal vs. arbuscular mycorrhizal trees. Furthermore, nitrogen deposition has contrasting effects on arbuscular vs. ectomycorrhizal demographic processes, favoring arbuscular mycorrhizal trees at the expense of ectomycorrhizal trees, and is spatially correlated with reduced soil carbon stocks. This implies future changes in nitrogen deposition may alter the capacity of forests to sequester carbon and offset climate change via interactions with the forest microbiome.},
}
@article {pmid30051849,
year = {2018},
author = {Bracewell, RR and Vanderpool, D and Good, JM and Six, DL},
title = {Cascading speciation among mutualists and antagonists in a tree-beetle-fungi interaction.},
journal = {Proceedings. Biological sciences},
volume = {285},
number = {1881},
pages = {},
doi = {10.1098/rspb.2018.0694},
pmid = {30051849},
issn = {1471-2954},
abstract = {Cascading speciation is predicted to occur when multiple interacting species diverge in parallel as a result of divergence in one species promoting adaptive differentiation in other species. However, there are few examples where ecological interactions among taxa have been shown to result in speciation that cascades across multiple trophic levels. Here, we test for cascading speciation occurring among the western pine beetle (Dendroctonus brevicomis), its primary host tree (Pinus ponderosa), and the beetle's fungal mutualists (Ceratocystiopsis brevicomi and Entomocorticium sp. B). We assembled genomes for the beetle and a fungal symbiont and then generated reduced representation genomic data (RADseq) from range-wide samples of these three interacting species. Combined with published data for the host tree, we present clear evidence that the tree, the beetle, and the fungal symbionts are all genetically structured into at least two distinct groups that have strongly codiverged with geographical isolation. We then combine our genomic results with diverse population and laboratory-based data to show evidence for reproductive isolation at each level of the cascade and for coevolution of both antagonistic and mutualistic species interactions within this complex network.},
}
@article {pmid30050553,
year = {2018},
author = {Liao, D and Sun, X and Wang, N and Song, F and Liang, Y},
title = {Tomato LysM Receptor-Like Kinase SlLYK12 Is Involved in Arbuscular Mycorrhizal Symbiosis.},
journal = {Frontiers in plant science},
volume = {9},
number = {},
pages = {1004},
doi = {10.3389/fpls.2018.01004},
pmid = {30050553},
issn = {1664-462X},
abstract = {Arbuscular mycorrhiza (AM) is a widespread symbiotic relationship between plants and fungi (Glomeromycota), which improves the supply of water and nutrients to host plants. AM symbiosis is set in motion by fungal chitooligosaccharides and lipochitooligosaccharides, which are perceived by plant-specific LysM-type receptor kinases (LYK). In rice this involves OsCERK1, a LYK also essential for chitin triggered innate immunity. In contrast in legumes, the CERK1 homologous gene experienced duplication events resulting in subfunctionalization. However, it remains unknown whether this subfunctionalization is legume-specific, or has occurred also in other dicot plant species. We identified four CERK1 homologs in tomato (SlLYK1, SlLYK11, SlLYK12, and SlLYK13) and investigated their roles in chitin signaling and AM symbiosis. We found that knockdown of SlLYK12 in tomato significantly reduced AM colonization, whereas chitin-induced responses were unaffected. In contrast, knockdown of SlLYK1 resulted in reduced responses to chitin, but did not alter responses to AM fungi. Moreover, ectopic overexpression of SlLYK1 and SlLYK13 in Nicotiana benthamiana induced cell death, whereas SlLYK12 overexpression did not. Based on our results and comparison with rice OsCERK1, we hypothesize that OsCERK1 orthologs in tomato underwent gene duplication, leading to the subfunctionalization of immunity and symbiosis.},
}
@article {pmid30050425,
year = {2018},
author = {Sandini, G and Mohan, V and Sciutti, A and Morasso, P},
title = {Social Cognition for Human-Robot Symbiosis-Challenges and Building Blocks.},
journal = {Frontiers in neurorobotics},
volume = {12},
number = {},
pages = {34},
doi = {10.3389/fnbot.2018.00034},
pmid = {30050425},
issn = {1662-5218},
abstract = {The next generation of robot companions or robot working partners will need to satisfy social requirements somehow similar to the famous laws of robotics envisaged by Isaac Asimov time ago (Asimov, 1942). The necessary technology has almost reached the required level, including sensors and actuators, but the cognitive organization is still in its infancy and is only partially supported by the current understanding of brain cognitive processes. The brain of symbiotic robots will certainly not be a &quot;positronic&quot; replica of the human brain: probably, the greatest part of it will be a set of interacting computational processes running in the cloud. In this article, we review the challenges that must be met in the design of a set of interacting computational processes as building blocks of a cognitive architecture that may give symbiotic capabilities to collaborative robots of the next decades: (1) an animated body-schema; (2) an imitation machinery; (3) a motor intentions machinery; (4) a set of physical interaction mechanisms; and (5) a shared memory system for incremental symbiotic development. We would like to stress that our approach is totally un-hierarchical: the five building blocks of the shared cognitive architecture are fully bi-directionally connected. For example, imitation and intentional processes require the &quot;services&quot; of the animated body schema which, on the other hand, can run its simulations if appropriately prompted by imitation and/or intention, with or without physical interaction. Successful experiences can leave a trace in the shared memory system and chunks of memory fragment may compete to participate to novel cooperative actions. And so on and so forth. At the heart of the system is lifelong training and learning but, different from the conventional learning paradigms in neural networks, where learning is somehow passively imposed by an external agent, in symbiotic robots there is an element of free choice of what is worth learning, driven by the interaction between the robot and the human partner. The proposed set of building blocks is certainly a rough approximation of what is needed by symbiotic robots but we believe it is a useful starting point for building a computational framework.},
}
@article {pmid30049880,
year = {2018},
author = {Dinh, C and Farinholt, T and Hirose, S and Zhuchenko, O and Kuspa, A},
title = {Lectins modulate the microbiota of social amoebae.},
journal = {Science (New York, N.Y.)},
volume = {361},
number = {6400},
pages = {402-406},
doi = {10.1126/science.aat2058},
pmid = {30049880},
issn = {1095-9203},
support = {P01 HD039691/HD/NICHD NIH HHS/United States ; },
mesh = {Biological Transport ; DNA, Bacterial/metabolism ; Dictyostelium/*metabolism/*microbiology ; Discoidins/*metabolism ; Klebsiella pneumoniae/metabolism/*physiology ; Microbiota/*physiology ; Symbiosis ; },
abstract = {The social amoeba Dictyostelium discoideum maintains a microbiome during multicellular development; bacteria are carried in migrating slugs and as endosymbionts within amoebae and spores. Bacterial carriage and endosymbiosis are induced by the secreted lectin discoidin I that binds bacteria, protects them from extracellular killing, and alters their retention within amoebae. This altered handling of bacteria also occurs with bacteria coated by plant lectins and leads to DNA transfer from bacteria to amoebae. Thus, lectins alter the cellular response of D. discoideum to bacteria to establish the amoebae's microbiome. Mammalian cells can also maintain intracellular bacteria when presented with bacteria coated with lectins, so heterologous lectins may induce endosymbiosis in animals. Our results suggest that endogenous or environmental lectins may influence microbiome homeostasis across eukaryotic phylogeny.},
}
@article {pmid30049746,
year = {2018},
author = {James, EB and Feng, H and Wilson, ACC},
title = {mTOR Complex 1 Implicated in Aphid/Buchnera Host/Symbiont Integration.},
journal = {G3 (Bethesda, Md.)},
volume = {8},
number = {9},
pages = {3083-3091},
doi = {10.1534/g3.118.200398},
pmid = {30049746},
issn = {2160-1836},
abstract = {Obligate nutritional endosymbioses are arguably the most intimate of all interspecific associations. While many insect nutritional endosymbioses are well studied, a full picture of how two disparate organisms, a bacterial endosymbiont and a eukaryotic host, are integrated is still lacking. The mTOR pathway is known to integrate nutritional conditions with cell growth and survival in eukaryotes. Characterization and localization of amino acid transporters in aphids suggest the mTOR pathway as a point of integration between an aphid host and its amino acid-provisioning endosymbiont Buchnera aphidicola The mTOR pathway is unannotated in aphids and unstudied in any nutritional endosymbiosis. We annotated mTOR pathway genes in two aphid species, Acyrthosiphon pisum and Myzus persicae, using both BLASTp searches and Hidden Markov Models. Using previously collected RNAseq data we constructed new reference transcriptomes for bacteriocyte, gut, and whole insect tissue for three lines of M. persicae Annotation of the mTOR pathway identified homologs of all known invertebrate mTOR genes in both aphid species with some duplications. Differential expression analysis showed that genes specific to the amino acid-sensitive mTOR Complex 1 were more highly expressed in bacteriocytes than genes specific to the amino acid-insensitive mTOR Complex 2. Almost all mTOR genes involved in sensing amino acids showed higher expression in bacteriocytes than in whole insect tissue. When compared to gut, the putative glutamine/arginine sensing transporter ACYPI000333, an ortholog of SLC38A9, showed 6.5 times higher expression in bacteriocytes. Our results suggest that the mTOR pathway may be functionally important in mediating integration of Buchnera into aphid growth and reproduction.},
}
@article {pmid30047576,
year = {2018},
author = {Cai, K and Yin, J and Chao, H and Ren, Y and Jin, L and Cao, Y and Duanmu, D and Zhang, Z},
title = {A C3HC4-type RING finger protein regulates rhizobial infection and nodule organogenesis in Lotus japonicus.},
journal = {Journal of integrative plant biology},
volume = {60},
number = {9},
pages = {878-896},
doi = {10.1111/jipb.12703},
pmid = {30047576},
issn = {1744-7909},
support = {31370278//National Natural Science Foundation of China/ ; 2010CB126502//National Basic Research Program of China/ ; 2662015PY171//Fundamental Research Funds for the Central Universities/ ; },
mesh = {Gene Expression Regulation, Plant ; Loteae/cytology/*metabolism/microbiology ; Plant Proteins/genetics/*metabolism ; Rhizobium/*physiology ; Root Nodules, Plant/cytology/*metabolism/microbiology ; Signal Transduction/genetics/physiology ; Symbiosis/genetics/physiology ; },
abstract = {During the establishment of rhizobia-legume symbiosis, the cytokinin receptor LHK1 (Lotus Histidine Kinase 1) is essential for nodule formation. However, the mechanism by which cytokinin signaling regulates symbiosis remains largely unknown. In this study, an LHK1-interacting protein, LjCZF1, was identified and further characterized. LjCZF1 is a C3HC4-type RING finger protein that is highly conserved in plants. LjCZF1 specifically interacted with LHK1 in yeast two-hybrid, in vitro pull-down and co-immunoprecipitation assays conducted in tobacco. Phosphomimetic mutation of the potential threonine (T167D) phosphorylation site enhanced the interaction between LjCZF1 and LHK1, whereas phosphorylation mutation (T167A) eliminated this interaction. Transcript abundance of LjCZF1 was up-regulated significantly after inoculation with rhizobia. The LORE1 insertion mutant and clustered regularly interspaced short palindromic repeats (CRISPR)/CRISPR-associated protein 9-mediated knockout mutant Lotus japonicus plants demonstrated significantly reduced number of infection threads and nodules. In contrast, plants over-expressing LjCZF1 exhibited increased numbers of infection threads and nodules. Collectively, these data support the notion that LjCZF1 is a positive regulator of symbiotic nodulation, possibly through interaction with LHK1.},
}
@article {pmid30047196,
year = {2018},
author = {Bennett, GM and Mao, M},
title = {Comparative genomics of a quadripartite symbiosis in a planthopper host reveals the origins and rearranged nutritional responsibilities of anciently diverged bacterial lineages.},
journal = {Environmental microbiology},
volume = {},
number = {},
pages = {},
doi = {10.1111/1462-2920.14367},
pmid = {30047196},
issn = {1462-2920},
support = {IOS1347116//Division of Integrative Organismal Systems/ ; },
abstract = {Insects in the Auchenorrhyncha (Hemiptera: Suborder) established nutritional symbioses with bacteria approximately 300 million years ago (MYA). The suborder split early during its diversification (~ 250 MYA) into the Fulgoroidea (planthoppers) and Cicadomorpha (leafhoppers and cicadas). The two lineages share some symbionts, including Sulcia and possibly a Betaproteobacteria that collaboratively provide their hosts with 10 essential amino acids (EAA). Some hosts harbour three bacteria, as is common among planthoppers. However, genomic studies are currently restricted to the dual-bacterial symbioses found in Cicadomorpha, leaving the origins and functions of these more complex symbioses unclear. To address these questions, we sequenced the genomes and performed phylogenomic analyses of 'Candidatus Sulcia muelleri' (Bacteroidetes), 'Ca. Vidania fulgoroideae' (Betaproteobacteria) and 'Ca. Purcelliella pentastirinorum' (Gammaproteobacteria) from a planthopper (Cixiidae: Oliarus). In contrast to the Cicadomorpha, nutritional synthesis responsibilities are rearranged between the cixiid symbionts. Although Sulcia has a highly conserved genome across the Auchenorrhyncha, in the cixiids it is greatly reduced and provides only three EAAs. Vidania contributes the remaining seven EAAs. Phylogenomic results suggest that it represents an ancient symbiont lineage paired with Sulcia throughout the Auchenorrhyncha. Finally, Purcelliella was recently acquired from plant-insect associated bacteria (Pantoea-Erwinia) to provide B vitamins and metabolic support to its degenerate partners.},
}
@article {pmid30047115,
year = {2018},
author = {Cai, H and Bai, Y and Guo, C},
title = {Comparative genomics of 151 plant-associated bacteria reveal putative mechanisms underlying specific interactions between bacteria and plant hosts.},
journal = {Genes &amp; genomics},
volume = {40},
number = {8},
pages = {857-864},
doi = {10.1007/s13258-018-0693-1},
pmid = {30047115},
issn = {2092-9293},
support = {KGB201217//Youth Foundation of Harbin Normal University/International ; 2017YFD0101303//The National Key Research and Development Program of China/International ; },
mesh = {Amino Acids/genetics ; Bacteria/classification/*genetics/metabolism ; Genome, Bacterial/genetics ; Genomics ; Host-Pathogen Interactions/*genetics ; Humans ; Nitrogen Fixation/genetics ; *Phylogeny ; Plants/*genetics/metabolism/microbiology ; Symbiosis/genetics ; },
abstract = {Although much work has explored how microbes can benefit plant growth, the mechanisms underlying this intriguing process remain largely unknown, especially considering the diversity of bacteria that surrounds plants. The objective of the present study was to identify bacterial genes contributing to plant-microbe associations, beneficial effects, and host specificities. For this purpose, comparative genomics investigation of 151 plant-associated bacteria was performed. A principal component analysis of seven key genomic features revealed patterns in the specific properties of these bacteria: N2-fixing bacteria were more closely related to pathogenic ones than to beneficial bacteria. A common set of genes over-represented in these plant-associated bacteria were found to be remarkably similar in terms of (1) genetic information processing, (2) amino acid metabolism, (3) metabolism of cofactors and vitamins, (4) nucleotide metabolism, (5) human diseases, and (6) metabolism of terpenoids and polyketides. Although we did not detect a common genetic basis for these beneficial effects, further in-depth analysis revealed that each of five beneficial bacterial groups shared specific gene sets. Functional annotation showed that environmental information processing, genetic information processing and cellular processes predominated in these beneficial groups. Hypothesizing that plant-associated bacteria may have overlapping strategies to colonize their plant hosts, we successfully identified many putative genes that determine host specificities. Most of these genes were classified as transcription factors, enzymes, transporters, and chemotaxis regulators. Comparative genomics provides a powerful tool for helping to identify genes that are common among species. Genome-based views of plant-associated bacteria reveal specific interactions between bacteria and plant hosts.},
}
@article {pmid30046969,
year = {2018},
author = {Bultman, TL and McNeill, MR and Krueger, K and De Nicolo, G and Popay, AJ and Hume, DE and Mace, WJ and Fletcher, LR and Koh, YM and Sullivan, TJ},
title = {Complex Interactions among Sheep, Insects, Grass, and Fungi in a Simple New Zealand Grazing System.},
journal = {Journal of chemical ecology},
volume = {44},
number = {10},
pages = {957-964},
doi = {10.1007/s10886-018-0993-6},
pmid = {30046969},
issn = {1573-1561},
support = {1119775//National Science Foundation/ ; },
mesh = {Alkaloids/pharmacology ; Animals ; Ascomycota/metabolism/*physiology ; *Ecosystem ; *Lolium ; New Zealand ; Saliva/metabolism ; Sheep/*microbiology ; Symbiosis ; Weevils/drug effects/*microbiology ; },
abstract = {Epichloë fungi (Ascomycota) live within aboveground tissues of grasses and can have important implications for natural and managed ecosystems through production of alkaloids. Nonetheless, vertebrate herbivores may possess traits, like oral secretions, that mitigate effects of alkaloids. We tested if sheep saliva mitigates effects of Epichloë alkaloids on a beetle pest of perennial ryegrass (Lolium perenne L.) in a New Zealand pasture setting. Plants with one of several fungal isolates were clipped with scissors, grazed by sheep, or clipped with sheep saliva applied to cut ends of stems. We then assessed feeding damage by Argentine stem weevils on blade segments collected from experimental plants. We found that clipping plants induced synthesis of an alkaloid that reduces feeding by beetles and that sheep saliva mitigates this effect. Unexpectedly, the alkaloid (perloline) that explains variation in beetle feeding is one produced not by the endophyte, but rather by the plant. Yet, these effects depended upon fungal isolate. Such indirect, complex interactions may be much more common in both managed and natural grassland systems than typically thought and could have implications for managing grazing systems.},
}
@article {pmid30043308,
year = {2018},
author = {Berrabah, F and Salem, EHA and Garmier, M and Ratet, P},
title = {The Multiple Faces of the Medicago-Sinorhizobium Symbiosis.},
journal = {Methods in molecular biology (Clifton, N.J.)},
volume = {1822},
number = {},
pages = {241-260},
doi = {10.1007/978-1-4939-8633-0_16},
pmid = {30043308},
issn = {1940-6029},
abstract = {Medicago truncatula is able to perform a symbiotic association with Sinorhizobium spp. This interaction leads to the formation of a new root organ, the nodule, in which bacteria infect the host cells and fix atmospheric nitrogen for the plant benefit. Multiple and complex processes are essential for the success of this interaction from the recognition phase to nodule formation and functioning, and a wide range of plant host genes is required to orchestrate this phenomenon. Thanks to direct and reverse genetic as well as transcriptomic approaches, numerous genes involved in this symbiosis have been described and improve our understanding of this fantastic association. Herein we propose to update the recent molecular knowledge of how M. truncatula associates to its symbiotic partner Sinorhizobium spp.},
}
@article {pmid30043296,
year = {2018},
author = {Chen, Y and Chen, R},
title = {Physical Mutagenesis in Medicago truncatula Using Fast Neutron Bombardment (FNB) for Symbiosis and Developmental Biology Studies.},
journal = {Methods in molecular biology (Clifton, N.J.)},
volume = {1822},
number = {},
pages = {61-69},
doi = {10.1007/978-1-4939-8633-0_4},
pmid = {30043296},
issn = {1940-6029},
abstract = {Medicago truncatula has been selected as a model species for legume molecular genetics and functional genomics studies. With the completion of the Medicago truncatula cv. Jemalong A17 genome sequencing, a major challenge is to determine the function of the large number of genes in the genome. Development of diverse mutant resources is crucial for gene functional studies. In the past years, M2 seeds from over 150,000 Medicago truncatula mutant lines in the Jemalong A17 background have been generated coordinately at the Noble Research Institute, USA, and the John Innes Centre, UK, using fast neutron bombardment (FNB) mutagenesis. These mutant resources have been used in screening and characterization of different categories of mutants including symbiotic nitrogen fixation, nodule development, and growth and patterning of leaf, stem, and root system architecture in the legume system. Here, we describe the detail procedure that has been used for screening of mutants derived from fast neutron bombardment mutagenesis in Medicago truncatula.},
}
@article {pmid30043288,
year = {2018},
author = {Kirienko, AN and Porozov, YB and Malkov, NV and Akhtemova, GA and Le Signor, C and Thompson, R and Saffray, C and Dalmais, M and Bendahmane, A and Tikhonovich, IA and Dolgikh, EA},
title = {Role of a receptor-like kinase K1 in pea Rhizobium symbiosis development.},
journal = {Planta},
volume = {248},
number = {5},
pages = {1101-1120},
doi = {10.1007/s00425-018-2944-4},
pmid = {30043288},
issn = {1432-2048},
support = {16-16-10043//Russian Science Foundation/ ; 074-U01//Government of Russian Federation/ ; SPS//the Program Saclay Plant Sciences/ ; ANR-10-LABX-40//the Program Saclay Plant Sciences/ ; ERC-SEXYPARTH//FP7 Ideas: European Research Council/ ; },
mesh = {Blotting, Western ; Genetic Engineering/methods ; Peas/*enzymology/microbiology/physiology ; Plant Leaves/enzymology/metabolism ; Plant Proteins/*physiology ; Plants, Genetically Modified ; Protein Kinases/*physiology ; Reverse Transcriptase Polymerase Chain Reaction ; Rhizobium leguminosarum/*physiology ; *Symbiosis ; Tobacco/genetics ; Two-Hybrid System Techniques ; },
abstract = {MAIN CONCLUSION: The LysM receptor-like kinase K1 is involved in regulation of pea-rhizobial symbiosis development. The ability of the crop legume Pisum sativum L. to perceive the Nod factor rhizobial signals may depend on several receptors that differ in ligand structure specificity. Identification of pea mutants defective in two types of LysM receptor-like kinases (LysM-RLKs), SYM10 and SYM37, featuring different phenotypic manifestations and impaired at various stages of symbiosis development, corresponds well to this assumption. There is evidence that one of the receptor proteins involved in symbiosis initiation, SYM10, has an inactive kinase domain. This implies the presence of an additional component in the receptor complex, together with SYM10, that remains unknown. Here, we describe a new LysM-RLK, K1, which may serve as an additional component of the receptor complex in pea. To verify the function of K1 in symbiosis, several P. sativum non-nodulating mutants in the k1 gene were identified using the TILLING approach. Phenotyping revealed the blocking of symbiosis development at an appropriately early stage, strongly suggesting the importance of LysM-RLK K1 for symbiosis initiation. Moreover, the analysis of pea mutants with weaker phenotypes provides evidence for the additional role of K1 in infection thread distribution in the cortex and rhizobia penetration. The interaction between K1 and SYM10 was detected using transient leaf expression in Nicotiana benthamiana and in the yeast two-hybrid system. Since the possibility of SYM10/SYM37 complex formation was also shown, we tested whether the SYM37 and K1 receptors are functionally interchangeable using a complementation test. The interaction between K1 and other receptors is discussed.},
}
@article {pmid30043258,
year = {2018},
author = {Kusakabe, R and Taniguchi, T and Goomaral, A and Undarmaa, J and Yamanaka, N and Yamato, M},
title = {Arbuscular mycorrhizal fungal communities under gradients of grazing in Mongolian grasslands of different aridity.},
journal = {Mycorrhiza},
volume = {28},
number = {7},
pages = {621-634},
doi = {10.1007/s00572-018-0855-7},
pmid = {30043258},
issn = {1432-1890},
support = {Grant-in-Aid for Scientific Research (26304046)//Ministry of Education, Culture, Sports, Science, and Technology, Japan/ ; },
abstract = {Communities of arbuscular mycorrhizal (AM) fungi in Mongolian grassland were characterized under gradients of grazing intensity at three study sites of different aridity: mountain forest steppe at Hustai National Park (Hustai), and desert steppe at Mandalgovi and Bulgan. Grazing intensity was classified into three categories: lightly grazed (LG), moderately grazed (MG), and heavily grazed (HG). With regard to floristic composition, grazing decreased the shoot biomass of Poaceae species, especially Stipa spp. Distinctness of the AM fungal communities was observed among the three study sites, but most of the AM fungal operational taxonomic units (OTUs) that comprised over 1.0% of the total reads were ubiquitous. This result indicates that the AM fungal communities may be derived from similar AM fungal floras in correspondence with environmental factors. The composition of AM fungal communities differed significantly among the grazing intensities at all study sites. The relative abundance of the most dominant AM fungal OTU of the LG plots decreased with an increase in grazing intensity at all study sites. The mean proportions of the most dominant AM fungal OTUs also decreased with increased grazing intensity at Hustai. Dominance by a single AM fungal taxon may be a typical ecological feature of the AM fungal symbiosis, and grazing disturbs AM fungal community structure.},
}
@article {pmid30043257,
year = {2018},
author = {Garg, N and Bharti, A},
title = {Salicylic acid improves arbuscular mycorrhizal symbiosis, and chickpea growth and yield by modulating carbohydrate metabolism under salt stress.},
journal = {Mycorrhiza},
volume = {28},
number = {8},
pages = {727-746},
doi = {10.1007/s00572-018-0856-6},
pmid = {30043257},
issn = {1432-1890},
support = {F1-17.1/2012-13/RGNF-2012-13-SC-PUN-28969 /(SA-III/Website)//University Grants Commission/ ; BT/PR9466/AGR/21/231/2007 dated 17.06.2010//Department of Biotechnology , Ministry of Science and Technology/ ; },
abstract = {Salt stress is a major abiotic stress restricting plant growth and reproductive yield. Salicylic acid (SA) and arbuscular mycorrhizal (AM) symbioses play key roles in eliminating adverse effects of salt stress by modulating ion homeostasis and carbohydrate metabolism in crop plants. Sugars synthesized via carbohydrate metabolism act as osmotic adjustors and signaling molecules in activation of various defense responses against salt stress. The present study investigated the role of SA (0.5 mM) seed priming in establishment of AM symbiosis with Rhizoglomus intraradices and the impact on growth, ion-homeostasis, nutrient uptake, and sugar metabolism in Cicer arietinum L. (chickpea) genotypes under salt stress. Salinity had a negative correlation with plant growth and AM symbiosis in both genotypes with more negative effects in relatively salt-sensitive genotype than tolerant. SA enhanced the percent root colonization by significantly increasing the number of arbuscules and vesicles under salt stress. AM symbiosis was more effective in improving root biomass, root to shoot ratio, and nutrient acquisition than SA, while SA was more effective in maintaining ion equilibrium and modulating carbohydrate metabolism and reproductive yield when compared with AM inoculation. SA priming directed the utilization of total soluble sugars (TSS) towards reproductive attributes more efficiently than did AM inoculation by activating TSS metabolic consumption. In AM plants, TSS concentrations were more directed towards sink demand by the fungus itself rather than developing reproductive structures. SA priming further increased sugar export to roots of AM plants, thus favored AM symbiosis. Hence, SA seed priming-induced improvement in AM symbiosis can be a promising strategy in achieving sustainable production of chickpea genotypes under salt stress.},
}
@article {pmid30042780,
year = {2018},
author = {Wang, C and Reid, JB and Foo, E},
title = {The Art of Self-Control - Autoregulation of Plant-Microbe Symbioses.},
journal = {Frontiers in plant science},
volume = {9},
number = {},
pages = {988},
doi = {10.3389/fpls.2018.00988},
pmid = {30042780},
issn = {1664-462X},
abstract = {Plants interact with diverse microbes including those that result in nutrient-acquiring symbioses. In order to balance the energy cost with the benefit gained, plants employ a systemic negative feedback loop to control the formation of these symbioses. This is particularly well-understood in nodulation, the symbiosis between legumes and nitrogen-fixing rhizobia, and is known as autoregulation of nodulation (AON). However, much less is understood about the autoregulation of the ancient arbuscular mycorrhizal symbioses that form between Glomeromycota fungi and the majority of land plants. Elegant physiological studies in legumes have indicated there is at least some overlap in the genes and signals that regulate these two symbioses but there are major gaps in our understanding. In this paper we examine the hypothesis that the autoregulation of mycorrhizae (AOM) pathway shares some elements with AON but that there are also some important differences. By reviewing the current knowledge of the AON pathway, we have identified important directions for future AOM studies. We also provide the first genetic evidence that CLV2 (an important element of the AON pathway) influences mycorrhizal development in a non-legume, tomato and review the interaction of the autoregulation pathway with plant hormones and nutrient status. Finally, we discuss whether autoregulation may play a role in the relationships plants form with other microbes.},
}
@article {pmid30042740,
year = {2018},
author = {Salem, I and Ramser, A and Isham, N and Ghannoum, MA},
title = {The Gut Microbiome as a Major Regulator of the Gut-Skin Axis.},
journal = {Frontiers in microbiology},
volume = {9},
number = {},
pages = {1459},
doi = {10.3389/fmicb.2018.01459},
pmid = {30042740},
issn = {1664-302X},
abstract = {The adult intestine hosts a myriad of diverse bacterial species that reside mostly in the lower gut maintaining a symbiosis with the human habitat. In the current review, we describe the neoteric advancement in our comprehension of how the gut microbiota communicates with the skin as one of the main regulators in the gut-skin axis. We attempted to explore how this potential link affects skin differentiation and keratinization, its influence on modulating the cutaneous immune response in various diseases, and finally how to take advantage of this communication in the control of different skin conditions.},
}
@article {pmid30042191,
year = {2018},
author = {Nakajima, A and Vogelzang, A and Maruya, M and Miyajima, M and Murata, M and Son, A and Kuwahara, T and Tsuruyama, T and Yamada, S and Matsuura, M and Nakase, H and Peterson, DA and Fagarasan, S and Suzuki, K},
title = {IgA regulates the composition and metabolic function of gut microbiota by promoting symbiosis between bacteria.},
journal = {The Journal of experimental medicine},
volume = {215},
number = {8},
pages = {2019-2034},
doi = {10.1084/jem.20180427},
pmid = {30042191},
issn = {1540-9538},
abstract = {Immunoglobulin A (IgA) promotes health by regulating the composition and function of gut microbiota, but the molecular requirements for such homeostatic IgA function remain unknown. We found that a heavily glycosylated monoclonal IgA recognizing ovalbumin coats Bacteroides thetaiotaomicron (B. theta), a prominent gut symbiont of the phylum Bacteroidetes. In vivo, IgA alters the expression of polysaccharide utilization loci (PUL), including a functionally uncharacterized molecular family provisionally named Mucus-Associated Functional Factor (MAFF). In both mice and humans, MAFF is detected predominantly in mucus-resident bacteria, and its expression requires the presence of complex microbiota. Expression of the MAFF system facilitates symbiosis with other members of the phylum Firmicutes and promotes protection from a chemically induced model of colitis. Our data reveal a novel mechanism by which IgA promotes symbiosis and colonic homeostasis.},
}
@article {pmid30041474,
year = {2018},
author = {Lipa, P and Vinardell, JM and Kopcińska, J and Zdybicka-Barabas, A and Janczarek, M},
title = {Mutation in the pssZ Gene Negatively Impacts Exopolysaccharide Synthesis, Surface Properties, and Symbiosis of Rhizobium leguminosarum bv. trifolii with Clover.},
journal = {Genes},
volume = {9},
number = {7},
pages = {},
doi = {10.3390/genes9070369},
pmid = {30041474},
issn = {2073-4425},
abstract = {Rhizobium leguminosarum bv. trifolii is a soil bacterium capable of establishing a nitrogen-fixing symbiosis with clover plants (Trifolium spp.). This bacterium secretes large amounts of acidic exopolysaccharide (EPS), which plays an essential role in the symbiotic interaction with the host plant. This polymer is biosynthesized by a multi-enzymatic complex located in the bacterial inner membrane, whose components are encoded by a large chromosomal gene cluster, called Pss-I. In this study, we characterize R. leguminosarum bv. trifolii strain Rt297 that harbors a Tn5 transposon insertion located in the pssZ gene from the Pss-I region. This gene codes for a protein that shares high identity with bacterial serine/threonine protein phosphatases. We demonstrated that the pssZ mutation causes pleiotropic effects in rhizobial cells. Strain Rt297 exhibited several physiological and symbiotic defects, such as lack of EPS production, reduced growth kinetics and motility, altered cell-surface properties, and failure to infect the host plant. These data indicate that the protein encoded by the pssZ gene is indispensable for EPS synthesis, but also required for proper functioning of R. leguminosarum bv. trifolii cells.},
}
@article {pmid30040500,
year = {2018},
author = {Lopetuso, LR and Napoli, M and Rizzatti, G and Scaldaferri, F and Franceschi, F and Gasbarrini, A},
title = {Considering gut microbiota disturbance in the management of Helicobacter pylori infection.},
journal = {Expert review of gastroenterology &amp; hepatology},
volume = {12},
number = {9},
pages = {899-906},
doi = {10.1080/17474124.2018.1503946},
pmid = {30040500},
issn = {1747-4132},
abstract = {INTRODUCTION: Helicobacter pylori (Hp) infection produces drastic changes in the gastric microenvironment, which, in turn, influence the gastric microbiota composition and might be correlated with large intestinal microbiota changes. This excellent perturbing actor could trigger important modifications in the homeostatic functions exerted by gut commensals leading to a new gastrointestinal balance. At the same time, the therapeutic strategies used to eradicate Hp can modulate this physiological symbiosis, but can be also conversely affected by its properties. Area covered: The purpose of this review is to explore the reciprocal interplay between Hp infection and gut microbiota and analyze how microbial changes can influence the management of Hp eradication therapies. Expert commentary: While many studies have described Hp-dependent gut microbiota alterations, their clinical implications are only partially clear, as well as the mechanism of actions that sustain these processes. This represents a clear challenge for future research projects that will also need to understand which role is exerted by viruses, parasites, and yeasts.},
}
@article {pmid30039604,
year = {2018},
author = {Garzo, E and Rizzo, E and Fereres, A and Gomez, SK},
title = {High levels of arbuscular mycorrhizal fungus colonization on Medicago truncatula reduces plant suitability as a host for pea aphids (Acyrthosiphon pisum).},
journal = {Insect science},
volume = {},
number = {},
pages = {},
doi = {10.1111/1744-7917.12631},
pmid = {30039604},
issn = {1744-7917},
support = {//University of Northern Colorado/ ; },
abstract = {This study sheds light on a poorly understood area in insect-plant-microbe interactions, focusing on aphid probing and feeding behavior on plants with varying levels of arbuscular mycorrhizal (AM) fungus root colonization. It investigates a commonly occurring interaction of three species: pea aphid Acyrthosiphon pisum, barrel medic Medicago truncatula, and the AM fungus Rhizophagus irregularis, examining whether aphid-feeding behavior changes when insects feed on plants at different levels of AM fungus colonization (42% and 84% root length colonized). Aphid probing and feeding behavior was monitored throughout 8 h of recording using the electrical penetration graph (EPG) technique, also, foliar nutrient content and plant growth were measured. Summarizing, aphids took longer to reach their 1st sustained phloem ingestion on the 84% AM plants than on the 42% AM plants or on controls. Less aphids showed phloem ingestion on the 84% AM plants relative to the 42% AM plants. Shoots of the 84% AM plants had higher percent carbon (43.7%) relative to controls (40.5%), and the 84% AM plants had reduced percent nitrogen (5.3%) relative to the 42% AM plants (6%). In conclusion, EPG and foliar nutrient data support the hypothesis that modifications in plant anatomy (e.g., thicker leaves), and poor food quality (reduced nitrogen) in the 84% AM plants contribute to reduced aphid success in locating phloem and ultimately to differences in phloem sap ingestion. This work suggests that M. truncatula plants benefit from AM symbiosis not only because of increased nutrient uptake but also because of reduced susceptibility to aphids.},
}
@article {pmid30039484,
year = {2018},
author = {Kraiem, K and Wahab, MA and Kallali, H and Fra-Vazquez, A and Pedrouso, A and Mosquera-Corral, A and Jedidi, N},
title = {Effects of short- and long-term exposures of humic acid on the Anammox activity and microbial community.},
journal = {Environmental science and pollution research international},
volume = {},
number = {},
pages = {},
doi = {10.1007/s11356-018-2786-4},
pmid = {30039484},
issn = {1614-7499},
abstract = {Humic acid has a controversial effect on the biological treatment processes. Here, we have investigated humic acid effects on the Anammox activity by studying the nitrogen removal efficiencies in batch and continuous conditions and analyzing the microbial community using Fluorescence in situ hybridization (FISH) technique. The results showed that the Anammox activity was affected by the presence of humic acid at a concentration higher than 70 mg/L. In fact, in the presence of humic acid concentration of 200 mg/L, the Anammox activity decreased to 57% in batch and under continuous condition, the ammonium removal efficiencies of the reactor decreased from 78 to 41%. This reduction of Anammox activity after humic acid addition was highlighted by FISH analysis which revealed a considerable reduction of the abundance of Anammox bacteria and the bacteria living in symbiosis with them. Furthermore, a total inhibition of Candidatus Brocadia fulgida was observed. However, humic acid has promoted heterotrophic denitrifying bacteria which became dominant in the reactor. In fact, the evolution of the organic matter in the reactor showed that the added humic acid was used as carbon source by heterotrophic bacteria which explained the shift of metabolism to the favor of heterotrophic denitrifying bacteria. Accordingly, humic acid should be controlled in the influent to avoid Anammox activity inhibition.},
}
@article {pmid30038864,
year = {2018},
author = {West, NJ and Parrot, D and Fayet, C and Grube, M and Tomasi, S and Suzuki, MT},
title = {Marine cyanolichens from different littoral zones are associated with distinct bacterial communities.},
journal = {PeerJ},
volume = {6},
number = {},
pages = {e5208},
doi = {10.7717/peerj.5208},
pmid = {30038864},
issn = {2167-8359},
abstract = {The microbial diversity and function of terrestrial lichens have been well studied, but knowledge about the non-photosynthetic bacteria associated with marine lichens is still scarce. 16S rRNA gene Illumina sequencing was used to assess the culture-independent bacterial diversity in the strictly marine cyanolichen species Lichina pygmaea and Lichina confinis, and the maritime chlorolichen species Xanthoria aureola which occupy different areas on the littoral zone. Inland terrestrial cyanolichens from Austria were also analysed as for the marine lichens to examine further the impact of habitat/lichen species on the associated bacterial communities. The L. confinis and L. pygmaea communities were significantly different from those of the maritime Xanthoria aureola lichen found higher up on the littoral zone and these latter communities were more similar to those of the inland terrestrial lichens. The strictly marine lichens were dominated by the Bacteroidetes phylum accounting for 50% of the sequences, whereas Alphaproteobacteria, notably Sphingomonas, dominated the maritime and the inland terrestrial lichens. Bacterial communities associated with the two Lichina species were significantly different sharing only 33 core OTUs, half of which were affiliated to the Bacteroidetes genera Rubricoccus, Tunicatimonas and Lewinella, suggesting an important role of these species in the marine Lichina lichen symbiosis. Marine cyanolichens showed a higher abundance of OTUs likely affiliated to moderately thermophilic and/or radiation resistant bacteria belonging to the Phyla Chloroflexi, Thermi, and the families Rhodothermaceae and Rubrobacteraceae when compared to those of inland terrestrial lichens. This most likely reflects the exposed and highly variable conditions to which they are subjected daily.},
}
@article {pmid30037698,
year = {2018},
author = {Simon, C},
title = {Introduction: Do microbes in the female reproductive function matter?.},
journal = {Fertility and sterility},
volume = {110},
number = {3},
pages = {325-326},
doi = {10.1016/j.fertnstert.2018.06.041},
pmid = {30037698},
issn = {1556-5653},
abstract = {For more than a century, the uterine cavity has been considered a sterile site maintained by the cervical plug. Humans are like coral that need symbiosis with microorganisms to be completely functional. In the era of precision medicine, the endometrial factor and specifically the microbiological view have long been neglected in reproduction, because it was considered an old concept with no potential improvement. In the last decade, important discoveries, led by improving technology, namely next generation sequencing, have been made in the study of microbial communities not only in the vagina but also in the endometrial cavity and its implication in reproductive health and disease, particularly chronic endometritis. From these studies, we have learned that microbes interact with the host cells along the female reproductive tract generating the physical, chemical and biological environment that the embryo will encounter during the peri-implantation period and throughout pregnancy.},
}
@article {pmid30037122,
year = {2018},
author = {Del Prete, S and Bua, S and Zoccola, D and Alasmary, FAS and AlOthman, Z and Alqahtani, LS and Techer, N and Supuran, CT and Tambutté, S and Capasso, C},
title = {Comparison of the Anion Inhibition Profiles of the α-CA Isoforms (SpiCA1, SpiCA2 and SpiCA3) from the Scleractinian Coral Stylophora pistillata.},
journal = {International journal of molecular sciences},
volume = {19},
number = {7},
pages = {},
doi = {10.3390/ijms19072128},
pmid = {30037122},
issn = {1422-0067},
mesh = {Amino Acid Sequence ; Animals ; Anthozoa/*enzymology ; Carbonic Anhydrases/chemistry/genetics/*metabolism ; Molecular Sequence Data ; Protein Isoforms/genetics/*metabolism ; Recombinant Proteins/genetics/*metabolism ; },
abstract = {Carbonic anhydrases (CAs, EC 4.2.1.1) are widespread metalloenzymes used by living organisms to accelerate the CO₂ hydration/dehydration reaction at rates dramatically high compared to the uncatalyzed reaction. These enzymes have different isoforms and homologues and can be found in the form of cytoplasmic, secreted or membrane-bound proteins. CAs play a role in numerous physiological processes including biomineralization and symbiosis, as is the case in reef-building corals. Previously, molecular and biochemical data have been obtained at the molecular level in the branching coral Stylophora pistillata for two coral isoforms which differ significantly in their catalytic activity and susceptibility to inhibition with anions and sulfonamides. More recently it has been determined that the genome of S. pistillata encodes for 16 CAs. Here, we cloned, expressed, purified and characterized a novel α-CA, named SpiCA3, which is cytoplasmic and ubiquitously expressed in all the cell layers including the calcifying cells. SpiCA3 is the most effective CA among the coral isoforms investigated and the most efficient catalyst known up to date in Metazoa. We also investigated the inhibition profiles of SpiCA3 and compared it with those obtained for the two other isoforms in the presence of inorganic anions and other small molecules known to interfere with metalloenzymes. These results suggest that S. pistillata has adapted its CA isoforms to achieve the physiological functions in different physicochemical microenvironments.},
}
@article {pmid30034913,
year = {2017},
author = {Zhou, Z and Zhong, W},
title = {Targeting the gut barrier for the treatment of alcoholic liver disease.},
journal = {Liver research},
volume = {1},
number = {4},
pages = {197-207},
doi = {10.1016/j.livres.2017.12.004},
pmid = {30034913},
issn = {2096-2878},
support = {R01 AA018844/AA/NIAAA NIH HHS/United States ; R01 AA020212/AA/NIAAA NIH HHS/United States ; },
abstract = {Alcohol consumption remains one of the predominant causes of liver disease and liver-related death worldwide. Intriguingly, dysregulation of the gut barrier is a key factor promoting the pathogenesis of alcoholic liver disease (ALD). A functional gut barrier, which consists of a mucus layer, an intact epithelial monolayer and mucosal immune cells, supports nutrient absorption and prevents bacterial penetration. Compromised gut barrier function is associated with the progression of ALD. Indeed, alcohol consumption disrupts the gut barrier, increases gut permeability, and induces bacterial translocation both in ALD patients and in experimental models with ALD. Moreover, alcohol consumption also causes enteric dysbiosis with both numerical and proportional perturbations. Here, we review and discuss mechanisms of alcohol-induced gut barrier dysfunction to better understand the contribution of the gut-liver axis to the pathogenesis of ALD. Unfortunately, there is no effectual Food and Drug Administration-approved treatment for any stage of ALD. Therefore, we conclude with a discussion of potential strategies aimed at restoring the gut barrier in ALD. The principle behind antibiotics, prebiotics, probiotics and fecal microbiota transplants is to restore microbial symbiosis and subsequently gut barrier function. Nutrient-based treatments, such as dietary supplementation with zinc, niacin or fatty acids, have been shown to regulate tight junction expression, reduce intestinal inflammation, and prevent endotoxemia as well as liver injury caused by alcohol in experimental settings. Interestingly, saturated fatty acids may also directly control the gut microbiome. In summary, clinical and experimental studies highlight the significance and efficacy of the gut barrier in treating ALD.},
}
@article {pmid30033490,
year = {2018},
author = {Zhao, L and Ahmad, F and Lu, M and Zhang, W and Wickham, JD and Sun, J},
title = {Ascarosides Promote the Prevalence of Ophiostomatoid Fungi and an Invasive Pathogenic Nematode, Bursaphelenchus xylophilus.},
journal = {Journal of chemical ecology},
volume = {44},
number = {7-8},
pages = {701-710},
doi = {10.1007/s10886-018-0996-3},
pmid = {30033490},
issn = {1573-1561},
support = {31630013, 31272323//National Natural Science Foundation of China/ ; XDB11050100, XDB11030600//Chinese Academy of Sciences (CAS) Strategic Priority Research Program/ ; 863 plan: 2014AA020529//High Technology Research and Development Program (HTRDP) of China/ ; },
mesh = {Animals ; Biological Evolution ; China ; Coleoptera/*physiology ; Fungi/physiology ; Glycolipids/*metabolism ; Insect Vectors/physiology ; Pinus/*parasitology ; Plant Diseases/*parasitology ; Symbiosis ; Tylenchida/*microbiology/*physiology ; },
abstract = {Understanding the coevolution of pathogens and their associated mycoflora depend upon a proper elucidation of the basis of their chemical communication. In the case of pine wilt disease, the mutual interactions between cerambycid beetles, invasive pathogenic nematodes, (Bursaphelenchus xylophilus) and their symbiotic ophiostomatoid fungi provide a unique opportunity to understand the role of small molecules in mediating their chemical communication. Nematodes produce ascarosides, a highly conserved family of small molecules that serve essential functions in nematode biology and ecology. Here we demonstrated that the associated fungi, one of the key natural food resources of pine wood nematodes, can detect and respond to these ascarosides. We found that ascarosides significantly increase the growth of L. pini-densiflorae and Sporothrix sp. 1, which are native fungal species in China that form a symbiotic relationship with pinewood nematodes. Hyphal mass of L. pini-densiflorae increased when treated with asc-C5 compared to other ophiostomatoid species. Field results demonstrated that in forests where higher numbers of PWN were isolated from beetle galleries, L. pini-densiflorae had been prevalent; the same results were confirmed in laboratory studies. Furthermore, when treated with asc-C5, L. pini-densiflorae responded by increasing its production of spores, which leads to a higher likelihood of dispersal by insect vectors, hence explaining the dominance of L. pini-densiflorae over S. sp. 1 in the Tianwang and Nanlu Mountains within the Northern Forestry Centre of China. These findings provide an emphatic representation of coevolution of pine wood nematode and its associated fungi. Our results lay a broader foundation for a better understanding of inter-kingdom mutualisms and the chemical signals that mediate their establishment.},
}
@article {pmid30032373,
year = {2018},
author = {Wang, Q and Tang, H and Yuan, X and Zuo, J and Zhang, J and Gao, Z and Hong, J},
title = {Investigating vulnerability of ecological industrial symbiosis network based on automatic control theory.},
journal = {Environmental science and pollution research international},
volume = {25},
number = {27},
pages = {27321-27333},
doi = {10.1007/s11356-018-2753-0},
pmid = {30032373},
issn = {1614-7499},
support = {2017YFC0703100//National Key R&amp;D Plan/ ; 41471461//National Natural Science Foundation of China (CN)/ ; 2018GSF121005//Key R&amp;D Plan of Shandong Province/ ; 2015JC056//Fundamental Research Funds of Shandong University/ ; IFYT1401, IFYT14010//Innovation Fund of Shandong University/ ; },
abstract = {System fluctuations of eco-industrial symbiosis network (EISN) organization due to disturbance are very similar to the controller adjustment in the automatic control theory. Thus, a methodology is proposed in this study to assess the vulnerability of EISN based on the automatic control theory. The results show that the regulator plays a key role to enhance the resilience of the network system to vulnerability. Therefore, it is imperative to strengthen the real-time regulation and control of EISN so that the system stability is improved. In order to further explore the impact of various regulations on the system vulnerability, the influence of system stability is simulated by means of proportional, differential, and integral control. A case study with Guigang eco-industrial park (EIP) was undertaken to test this model. The results showed that when the system was disturbed at different positions, the key nodes which had great influence on system vulnerability could be selected according to the magnitude of simulation curve. By changing the ratio coefficient of proportional, differential, and integral units to adjust the ecological chain network, the system's resilience to vulnerability can be enhanced. Firstly, if basic conditions of EISN organization remain unchanged, the integral control of the policy support and infrastructure sharing should be strengthened. Secondly, the differential regulation should be improved continuously for the technological innovation capability of key node enterprises. Finally, the key chain filling projects should be introduced for proportional control so that the chain network design can be optimized from the source.},
}
@article {pmid30031478,
year = {2018},
author = {Liu, YH and Wang, ET and Jiao, YS and Tian, CF and Wang, L and Wang, ZJ and Guan, JJ and Singh, RP and Chen, WX and Chen, WF},
title = {Symbiotic characteristics of Bradyrhizobium diazoefficiens USDA 110 mutants associated with shrubby sophora (Sophora flavescens) and soybean (Glycine max).},
journal = {Microbiological research},
volume = {214},
number = {},
pages = {19-27},
doi = {10.1016/j.micres.2018.05.012},
pmid = {30031478},
issn = {1618-0623},
mesh = {Bradyrhizobium/genetics/*isolation &amp; purification/*physiology ; DNA Transposable Elements ; Gene Deletion ; Host Specificity ; Mutagenesis, Insertional ; Plant Root Nodulation ; Sophora/*microbiology ; Soybeans/*microbiology ; *Symbiosis ; },
abstract = {Site-specific insertion plasmid pVO155 was used to knockout the genes involved in the alternation of host range of strain Bradyrhizobium diazoefficiens USDA 110 from its original determinate-nodule-forming host soybean (Glycine max), to promiscuous and indeterminate-nodule-forming shrubby legume sophora (Sophora flavescens). Symbiotic phenotypes of these mutants inoculated to these two legumes, were compared to those infected by wild-type strain USDA 110. Six genes of the total fourteen Tn5 transposon mutated genes were broken using the pVO155 plasmid. Both Tn5 and pVO155-inserted mutants could nodulate S. flavescens with different morphologies of low-efficient indeterminate nodules. One to several rod or irregular bacteroids, containing different contents of poly-β-hydroxybutyrate or polyphosphate were found within the symbiosomes in nodulated cells of S. flavescens infected by the pVO155-inserted mutants. Moreover, none of bacteroids were observed in the pseudonodules of S. flavescens, infected by wild-type strain USDA 110. These mutants had the nodulation ability with soybean but the symbiotic efficiency reduced to diverse extents. These findings enlighten the complicated interactions between rhizobia and legumes, i. e., mutation of genes involved in metabolic pathways, transporters, chemotaxis and mobility could alter the rhizobial entry and development of the bacteroid inside the nodules of a new host legume.},
}
@article {pmid30030730,
year = {2018},
author = {Nouioui, I and Ghodhbane-Gtari, F and Jando, M and Tisa, LS and Klenk, HP and Gtari, M},
title = {Frankia torreyi sp. nov., the first actinobacterium of the genus Frankia Brunchorst 1886, 174AL isolated in axenic culture.},
journal = {Antonie van Leeuwenhoek},
volume = {},
number = {},
pages = {},
doi = {10.1007/s10482-018-1131-8},
pmid = {30030730},
issn = {1572-9699},
abstract = {Strain CpI1T was, in 1978, the first isolate of the genus Frankia to be obtained from Comptonia peregrina root nodules. In this study, a polyphasic approach was performed to identify the taxonomic position of strain CpI1T among the members of the genus Frankia. The strain contains meso-diaminopimelic acid as the diagnostic diamino acid and galactose, glucose, mannose, rhamnose, ribose and xylose as cell wall sugars. The polar lipids were found to consist of phosphatidylinositol, diphosphatidylglycerol, glycophospholipids, phosphatidylglycerol, an aminophospholipid and unidentified phospholipids and lipids. The predominant menaquinone was identified as MK-9 (H8), while the major fatty acid are iso-C16:0 and C17:1 ω 8c. The 16S rRNA gene sequence identity varies from 97.4 to 99.6% with the type strains of currently described Frankia species. Phylogenetic analyses based on 16S rRNA gene sequences and multi-locus sequence analysis (MLSA) using atp1, ftsZ, dnaK, gyrA and secA gene sequences showed that strain CpI1T is closely related to Frankia alni ACN14aT. The genome size of strain CpI1T is 7.6 Mb with a digital DNA G+C content of 72.4%. Digital DNA:DNA hybridization (values between strain CpI1T and its close phylogenetic relative F. alni ACN14aT was 44.1%, well below the threshold of 70% for distinguishing between bacterial genomic species. Based on the phenotypic, phylogenetic and genomic data, strain CpI1T (= DSM44263T = CECT9035T) warrants classification as the type strain of a novel species, for which the name Frankia torreyi sp. nov. is proposed.},
}
@article {pmid30030225,
year = {2018},
author = {Thompson, CM and Marsden, AE and Tischler, AH and Koo, J and Visick, KL},
title = {Vibrio fischeri Biofilm Formation Prevented by a Trio of Regulators.},
journal = {Applied and environmental microbiology},
volume = {84},
number = {19},
pages = {},
doi = {10.1128/AEM.01257-18},
pmid = {30030225},
issn = {1098-5336},
abstract = {Biofilms, complex communities of microorganisms surrounded by a self-produced matrix, facilitate attachment and provide protection to bacteria. A natural model used to study biofilm formation is the symbiosis between Vibrio fischeri and its host, the Hawaiian bobtail squid, Euprymna scolopes Host-relevant biofilm formation is a tightly regulated process and is observed in vitro only with strains that have been genetically manipulated to overexpress or disrupt specific regulators, primarily two-component signaling (TCS) regulators. These regulators control biofilm formation by dictating the production of the symbiosis polysaccharide (Syp-PS), the major component of the biofilm matrix. Control occurs both at and below the level of transcription of the syp genes, which are responsible for Syp-PS production. Here, we probed the roles of the two known negative regulators of biofilm formation, BinK and SypE, by generating double mutants. We also mapped and evaluated a point mutation using natural transformation and linkage analysis. We examined traditional biofilm formation phenotypes and established a new assay for evaluating the start of biofilm formation in the form of microscopic aggregates in shaking liquid cultures, in the absence of the known biofilm-inducing signal calcium. We found that wrinkled colony formation is negatively controlled not only by BinK and SypE but also by SypF. SypF is both required for and inhibitory to biofilm formation. Together, these data reveal that these three regulators are sufficient to prevent wild-type V. fischeri from forming biofilms under these conditions.IMPORTANCE Bacterial biofilms promote attachment to a variety of surfaces and protect the constituent bacteria from environmental stresses, including antimicrobials. Understanding the mechanisms by which biofilms form will promote our ability to resolve them when they occur in the context of an infection. In this study, we found that Vibrio fischeri tightly controls biofilm formation using three negative regulators; the presence of a single one of these regulators was sufficient to prevent full biofilm development, while disruption of all three permitted robust biofilm formation. This work increases our understanding of the functions of specific regulators and demonstrates the substantial negative control that one benign microbe exerts over biofilm formation, potentially to ensure that it occurs only under the appropriate conditions.},
}
@article {pmid30027377,
year = {2018},
author = {Wang, Q and Tang, H and Qiu, S and Yuan, X and Zuo, J},
title = {Robustness of eco-industrial symbiosis network: a case study of China.},
journal = {Environmental science and pollution research international},
volume = {25},
number = {27},
pages = {27203-27213},
doi = {10.1007/s11356-018-2764-x},
pmid = {30027377},
issn = {1614-7499},
support = {41471461//National Natural Science Foundation of China/ ; 2017YFC0703100//National Key R&amp;D Plan/ ; 2018GSF121005//Shandong Provincial Key R&amp;D Plan/ ; 2015JC056//Fundamental Research Funds of Shandong University/ ; },
abstract = {As a complex network, eco-industrial symbiosis network is featured with complexity, openness, and non-linearity. A methodology is proposed to analyze and optimize the eco-industrial symbiosis network from the perspective of complex network theory. Structural robustness index and performance robustness index are established as the analysis model. Consequently, a robust method is developed to optimize the eco-industrial symbiosis network system based on the percolation theory. A conceptual framework is put forward to improve the robustness of eco-industrial symbiosis network system by introducing the &quot;spare core&quot; enterprise which is validated by quantitative analysis. The empirical results show that the robustness of eco-industrial symbiosis network varies under both random failure and intentional disturbance scenarios. However, eco-industrial symbiosis network system has strong self-regulation capability as long as the core enterprise is still in operation. It is recommended that supplementary chain could be added to those enterprises with lower network node connectivity to form &quot;spare core&quot; enterprise. This can not only effectively reduce the dependence of other enterprises on core enterprises, but also further improve the robustness of eco-industrial symbiosis network. This methodology is practically validated by a case analysis of eco-industrial park in China. The findings provide useful inputs to the design and operation of eco-industrial parks.},
}
@article {pmid30026595,
year = {2018},
author = {Gully, D and Czernic, P and Cruveiller, S and Mahé, F and Longin, C and Vallenet, D and François, P and Nidelet, S and Rialle, S and Giraud, E and Arrighi, JF and DasGupta, M and Cartieaux, F},
title = {Transcriptome Profiles of Nod Factor-independent Symbiosis in the Tropical Legume Aeschynomene evenia.},
journal = {Scientific reports},
volume = {8},
number = {1},
pages = {10934},
doi = {10.1038/s41598-018-29301-0},
pmid = {30026595},
issn = {2045-2322},
support = {IFC/5103-4/2014/543//Indo-French Centre for the Promotion of Advanced Research (Centre Franco-Indien pour la Promotion de la Recherche Avanc&amp;#x00E9;e)/ ; IFC/5103-4/2014/543//Indo-French Centre for the Promotion of Advanced Research (Centre Franco-Indien pour la Promotion de la Recherche Avanc&amp;#x00E9;e)/ ; IFC/5103-4/2014/543//Indo-French Centre for the Promotion of Advanced Research (Centre Franco-Indien pour la Promotion de la Recherche Avanc&amp;#x00E9;e)/ ; ANR-SESAM-2010-BLAN-170801//Agence Nationale de la Recherche (French National Research Agency)/ ; ANR-SESAM-2010-BLAN-170801//Agence Nationale de la Recherche (French National Research Agency)/ ; ANR-SESAM-2010-BLAN-170801//Agence Nationale de la Recherche (French National Research Agency)/ ; ANR-SESAM-2010-BLAN-170801//Agence Nationale de la Recherche (French National Research Agency)/ ; },
abstract = {Nod factors (NF) were assumed to be indispensable for the establishment of a rhizobium-legume symbiosis until the discovery that certain Bradyrhizobium strains interacting with certain Aeschynomene species lack the canonical nodABC genes required for their synthesis. So far, the molecular dialogue between Aeschynomene and its symbionts remains an open question. Here we report a time course transcriptional analysis of Aeschynomene evenia in response to inoculation with Bradyrhizobium ORS278. The NF-independent symbiotic process was monitored at five time points between bacterial infection and nodule maturity. The five time points correspond to three specific events, root infection by crack entry, nodule organogenesis, and the establishment of the nitrogen fixing process. During the third stage, about 80 NCR-like genes and eight symbiotic genes known to be involved in signaling, bacterial infection or nodulation regulation were highly expressed. Comparative gene expression analyses at the five time points also enabled the selection of genes with an expression profile that makes them promising markers to monitor early plant responses to bacteria. Such markers could be used in bioassays to identify the nature of the bacterial signal(s). Our data represent valuable resources for investigation of this Nod factor-independent symbiosis.},
}
@article {pmid30025219,
year = {2018},
author = {Sujkowska-Rybkowska, M and Znojek, E},
title = {Localization of calreticulin and calcium ions in mycorrhizal roots of Medicago truncatula in response to aluminum stress.},
journal = {Journal of plant physiology},
volume = {229},
number = {},
pages = {22-31},
doi = {10.1016/j.jplph.2018.05.014},
pmid = {30025219},
issn = {1618-1328},
mesh = {Aluminum/*toxicity ; Calcium/*metabolism ; Calreticulin/*metabolism ; Gene Expression Regulation, Plant/drug effects/genetics ; Medicago truncatula/drug effects/*metabolism/*microbiology ; Mycorrhizae/*physiology ; Plant Roots/drug effects/metabolism/microbiology ; },
abstract = {Aluminum (Al) toxicity limits growth and symbiotic interactions of plants. Calcium plays essential roles in abiotic stresses and legume-Rhizobium symbiosis, but the sites and mechanism of Ca2+ mobilization during mycorrhizae have not been analyzed. In this study, the changes of cytoplasmic Ca2+ and calreticulin (CRT) in Medicago truncatula mycorrhizal (MR) and non-mycorrizal (NM) roots under short Al stress [50 μM AlCl3 pH 4.3 for 3 h] were analyzed. Free Ca2+ ions were detected cytochemically by their reaction with potassium pyroantimonate and anti-CRT antibody was used to locate this protein in Medicago roots by immunocytochemical methods. In MR and NM roots, Al induced accumulation of CRT and free Ca2+. Similar calcium and CRT distribution in the MR were found at the surface of fungal structures (arbuscules and intercellular hyphae), cell wall and in plasmodesmata, and in plant and fungal intracellular compartments. Additionally, degenerated arbuscules were associated with intense Ca2+ and CRT accumulation. In NM roots, Ca2+ and CRT epitopes were observed in the stele, near wall of cortex and endodermis. The present study provides new insight into Ca2+ storage and mobilization in mycorrhizae symbiosis. The colocalization of CRT and Ca2+ suggests that CRT is essential for calcium mobilization for normal mycorrhiza development and response to Al stress.},
}
@article {pmid30022986,
year = {2018},
author = {Gough, C and Cottret, L and Lefebvre, B and Bono, JJ},
title = {Evolutionary History of Plant LysM Receptor Proteins Related to Root Endosymbiosis.},
journal = {Frontiers in plant science},
volume = {9},
number = {},
pages = {923},
doi = {10.3389/fpls.2018.00923},
pmid = {30022986},
issn = {1664-462X},
abstract = {LysM receptor-like kinases (LysM-RLKs), which are specific to plants, can control establishment of both the arbuscular mycorrhizal (AM) and the rhizobium-legume (RL) symbioses in response to signal molecules produced, respectively, by the fungal and bacterial symbiotic partners. While most studies on these proteins have been performed in legume species, there are also important findings that demonstrate the roles of LysM-RLKs in controlling symbiosis in non-legume plants. Phylogenomic studies, which have revealed the presence or absence of certain LysM-RLKs among different plant species, have provided insight into the evolutionary mechanisms underlying both the acquisition and the loss of symbiotic properties. The role of a key nodulation LysM-RLK, NFP/NFR5, in legume plants has thus probably been co-opted from an ancestral role in the AM symbiosis, and has been lost in most plant species that have lost the ability to establish the AM or the RL symbiosis. Another LysM-RLK, LYK3/NFR1, that controls the RL symbiosis probably became neo-functionalised following two rounds of gene duplication. Evidence suggests that a third LysM-RLK, LYR3/LYS12, is also implicated in perceiving microbial symbiotic signals, and this protein could have roles in symbiosis and/or plant immunity in different plant species. By focusing on these three LysM-RLKs that are widespread in plants we review their evolutionary history and what this can tell us about the evolution of both the RL and the AM symbioses.},
}
@article {pmid30022157,
year = {2018},
author = {Li, Y and Liles, MR and Halanych, KM},
title = {Endosymbiont genomes yield clues of tubeworm success.},
journal = {The ISME journal},
volume = {12},
number = {11},
pages = {2785-2795},
doi = {10.1038/s41396-018-0220-z},
pmid = {30022157},
issn = {1751-7370},
support = {IOS-0843473//National Science Foundation (NSF)/ ; DEB-1036537//National Science Foundation (NSF)/ ; IOS-0843473//National Science Foundation (NSF)/ ; },
abstract = {Forty years after discovery of chemosynthetic symbiosis in the tubeworm Riftia pachyptila, how organisms maintain their unique host-symbiont associations at the cellular level is still largely unknown. Previous studies primarily focus on symbionts associated with host lineages living in hydrothermal vents. To understand physiological adaptations and evolution in these holobiont systems in markedly different habitats, we characterized four novel siboglinid-symbiont genomes spanning deep-sea seep and sedimented environments. Our comparative analyses suggest that all sampled siboglinid chemoautotrophic symbionts, except for frenulate symbionts, can use both rTCA and Calvin cycle for carbon fixation. We hypothesize that over evolutionary time siboglinids have been able to utilize different bacterial lineages allowing greater metabolic flexibility of carbon fixation (e.g., rTCA) enabling tubeworms to thrive in more reducing habitats, such as vents and seeps. Moreover, we show that sulfur metabolism and molecular mechanisms related to initial infection are remarkably conserved across chemoautotrophic symbionts in different habitats. Unexpectedly, we find that the ability to use hydrogen, as an additional energy source, is potentially more widespread than previously recognized. Our comparative genomic results help elucidate potential mechanisms used to allow chemosynthetically dependent holobionts adapt to, and evolve in, different environments.},
}
@article {pmid30019339,
year = {2018},
author = {Elmnasri, K and Hamdi, C and Ettoumi, B and Crotti, E and Guesmi, A and Najjari, A and Doudoumis, V and Boudabous, A and Daffonchio, D and Tsiamis, G and Cherif, A},
title = {Highly divergent Mollicutes symbionts coexist in the scorpion Androctonus australis.},
journal = {Journal of basic microbiology},
volume = {58},
number = {10},
pages = {827-835},
doi = {10.1002/jobm.201800144},
pmid = {30019339},
issn = {1521-4028},
support = {BIODESERT GA N° 245746//Seventh Framework Programme CSA-SA/ ; LR11ES31//Ministry of Higher Education and Scientific research, Tunisia/ ; },
mesh = {Animals ; Bacteria/classification/genetics ; Bacterial Physiological Phenomena ; DNA, Bacterial/genetics ; *Genetic Variation ; Host Specificity ; India ; Mexico ; *Phylogeny ; RNA, Ribosomal, 16S/genetics ; Scorpions/*microbiology ; Sequence Analysis, DNA ; *Symbiosis ; Tenericutes/*classification/genetics/*physiology ; },
abstract = {Androctonus australis is one of the most ubiquitous and common scorpion species in desert and arid lands from North Africa to India and it has an important ecological role and social impact. The bacterial community associated to this arachnid is unknown and we aimed to dissect its species composition in the gut, gonads, and venom gland. A 16S rRNA gene culture-independent diversity analysis revealed, among six other taxonomic groups (Firmicutes, Betaproteobacteria, Gammaproteobacteria, Flavobacteria, Actinobacteria, and Cyanobacteria), a dominance of Mollicutes phylotypes recorded both in the digestive tract and the gonads. These related Mollicutes include two Spiroplasma phylotypes (12.5% of DGGE bands and 15% of clones), and a new Mycoplasma cluster (80% of clones) showing 16S rRNA sequence identities of 95 and 93% with Mollicutes detected in the Mexican scorpions Centruroides limpidus and Vaejovis smithi, respectively. Such scorpion-associated Mollicutes form a new lineage that share a distant ancestor with Mycoplasma hominis. The observed host specificity with the apparent phylogenetic divergence suggests a relatively long co-evolution of these symbionts with the scorpion hosts. From the ecological point of view, such association may play a beneficial role for the host fitness, especially during dormancy or molt periods.},
}
@article {pmid30019154,
year = {2018},
author = {Scopel, W and Cônsoli, FL},
title = {Culturable symbionts associated with the reproductive and digestive tissues of the Neotropical brown stinkbug Euschistus heros.},
journal = {Antonie van Leeuwenhoek},
volume = {111},
number = {12},
pages = {2413-2424},
doi = {10.1007/s10482-018-1130-9},
pmid = {30019154},
issn = {1572-9699},
support = {2011/50877-0//Fundação de Amparo à Pesquisa do Estado de São Paulo/ ; 2013-2/312094//Conselho Nacional de Desenvolvimento Científico e Tecnológico/ ; },
abstract = {Symbionts are widely distributed in eukaryotes, and potentially affect the physiology, ecology and evolution of their host. Most insects harbour free-living bacteria in their haemocoel and gut lumen, intracellular-living bacteria in a range of tissues or bacteria in host-derived specialized cells. Stinkbugs, as do many arthropods, harbour extracellular bacteria in the gut that may affect the fitness of their host. This study identified the culturable symbionts associated with the ovaries, spermatheca, seminal vesicle and posterior midgut region (V4) of males and females of Euschistus heros (F.) (Hemiptera: Pentatomidae). Several culture media were used to isolate the bacteria associated with these structures. The selected colonies (morphotypes) were cultured in liquid medium, subjected to genomic DNA extraction, 16S rRNA gene amplification, and restriction fragment length polymorphism (RFLP) analyses. Morphotypes with distinct RFLP patterns were purified and sequenced, and the sequences obtained were used for putative identification and phylogenetic analysis. Comparison of the sequences with those available in the EzTaxon-e database and the use of a matrix of paired distances grouped the isolates in phylotypes belonging to the Phylum Proteobacteria. Proteobacteria was represented by γ-Proteobacteria phylotypes belonging to Enterobacteriaceae, while Firmicutes had Bacilli phylotypes distributed in Enterococcaceae and Staphylococcaceae. Some of the phylotypes identified were associated exclusively with single structures, such as ovaries, spermatheca and the V4 midgut region of males and females. All culturable bacteria associated with the seminal vesicle were also associated with other tissues.},
}
@article {pmid30018611,
year = {2018},
author = {Berdeni, D and Cotton, TEA and Daniell, TJ and Bidartondo, MI and Cameron, DD and Evans, KL},
title = {The Effects of Arbuscular Mycorrhizal Fungal Colonisation on Nutrient Status, Growth, Productivity, and Canker Resistance of Apple (Malus pumila).},
journal = {Frontiers in microbiology},
volume = {9},
number = {},
pages = {1461},
doi = {10.3389/fmicb.2018.01461},
pmid = {30018611},
issn = {1664-302X},
abstract = {We assess whether arbuscular mycorrhizal fungi (AMF) improve growth, nutritional status, phenology, flower and fruit production, and disease resistance in woody perennial crops using apple (Malus pumila) as a study system. In a fully factorial experiment, young trees were grown for 3 years with or without AMF (Funneliformis mosseae and Rhizophagus irregularis), and with industrial standard fertiliser applications or restricted fertiliser (10% of standard). We use two commercial scions (Dabinett and Michelin) and rootstocks (MM111 and MM106). Industrial standard fertiliser applications reduced AMF colonisation and root biomass, potentially increasing drought sensitivity. Mycorrhizal status was influenced by above ground genotypes (scion type) but not rootstocks, indicating strong interactions between above and below ground plant tissue. The AMF inoculation significantly increased resistance to Neonectria ditissima, a globally economically significant fungal pathogen of apple orchards, but did not consistently alter leaf nutrients, growth, phenology or fruit and flower production. This study significantly advances understanding of AMF benefits to woody perennial crops, especially increased disease resistance which we show is not due to improved tree nutrition or drought alleviation. Breeding programmes and standard management practises can limit the potential for these benefits.},
}
@article {pmid30018360,
year = {2018},
author = {Borovec, O and Vohník, M},
title = {Ontogenetic transition from specialized root hairs to specific root-fungus symbiosis in the dominant Mediterranean seagrass Posidonia oceanica.},
journal = {Scientific reports},
volume = {8},
number = {1},
pages = {10773},
doi = {10.1038/s41598-018-28989-4},
pmid = {30018360},
issn = {2045-2322},
abstract = {Terrestrial plants typically take up nutrients through roots or mycorrhizae while freshwater plants additionally utilize leaves. Their nutrient uptake may be enhanced by root hairs whose occurrence is often negatively correlated with mycorrhizal colonization. Seagrasses utilize both leaves and roots and often form root hairs, but seem to be devoid of mycorrhizae. The Mediterranean seagrass Posidonia oceanica is an exception: its adults commonly lack root hairs and regularly form a specific association with a single pleosporalean fungus. Here we show that at two sites in the southern Adriatic, all its seedlings possessed abundant root hairs with peculiar morphology (swollen terminal parts) and anatomy (spirally formed cell walls) as apparent adaptations for better attachment to the substrate and increase of breaking strain. Later on, their roots became colonized by dark septate mycelium while root hairs were reduced. In adults, most of terminal fine roots possessed the specific fungal association while root hairs were absent. These observations indicate for the first time that processes regulating transition from root hairs to root fungal colonization exist also in some seagrasses. This ontogenetic shift in root traits may suggests an involvement of the specific root symbiosis in the nutrient uptake by the dominant Mediterranean seagrass.},
}
@article {pmid30018085,
year = {2018},
author = {Burke, GR and Walden, KKO and Whitfield, JB and Robertson, HM and Strand, MR},
title = {Whole Genome Sequence of the Parasitoid Wasp Microplitis demolitor That Harbors an Endogenous Virus Mutualist.},
journal = {G3 (Bethesda, Md.)},
volume = {8},
number = {9},
pages = {2875-2880},
doi = {10.1534/g3.118.200308},
pmid = {30018085},
issn = {2160-1836},
support = {F32 AI096552/AI/NIAID NIH HHS/United States ; },
abstract = {Microplitis demolitor (Hymenoptera: Braconidae) is a parasitoid used as a biological control agent to control larval-stage Lepidoptera and serves as a model for studying the function and evolution of symbiotic viruses in the genus Bracovirus Here we present the M. demolitor genome (assembly version 2.0), with a genome size of 241 Mb, and a N50 scaffold and contig size of 1.1 Mb and 14 Kb, respectively. Using RNA-Seq data and manual annotation of genes of viral origin, we produced a high-quality gene set that includes 18,586 eukaryotic and 171 virus-derived protein-coding genes. Bracoviruses are dsDNA viruses with unusual genome architecture, in which the viral genome is integrated into the wasp genome and is comprised of two distinct components: proviral segments that are amplified, circularized, and packaged into virions for export into the wasp's host via oviposition; and replication genes. This genome assembly revealed that at least two scaffolds contain both nudivirus-like genes and proviral segments, demonstrating that at least some of these components are near each other in the genome on a single chromosome. The updated assembly and annotation are available in several publicly accessible databases; including the National Center for Biotechnology Information and the Ag Data Commons. In addition, all raw sequence data available for M. demolitor have been consolidated and are available for visualization at the i5k Workspace. This whole genome assembly and annotation represents the only genome-scale, annotated assembly from the lineage of parasitoid wasps that has associations with bracoviruses (the 'microgastroid complex'), providing important baseline knowledge about the architecture of co-opted virus symbiont genomes.},
}
@article {pmid30017075,
year = {2018},
author = {Kamani, J and Harrus, S and Nachum-Biala, Y and Salant, H and Mumcuoglu, KY and Baneth, G},
title = {Pathogenic and endosymbiont apicomplexans in Ctenocephalides felis (Siphonaptera: Pulicidae) from cats in Jerusalem, Israel.},
journal = {Comparative immunology, microbiology and infectious diseases},
volume = {57},
number = {},
pages = {29-33},
doi = {10.1016/j.cimid.2018.03.002},
pmid = {30017075},
issn = {1878-1667},
mesh = {Animals ; Apicomplexa/classification/genetics/*isolation &amp; purification ; Babesia/classification/genetics/*isolation &amp; purification ; Cat Diseases/*epidemiology/parasitology ; Cats ; Ctenocephalides/parasitology/physiology ; Eucoccidiida/classification/genetics/*isolation &amp; purification ; Female ; Flea Infestations/epidemiology/parasitology/*veterinary ; Israel/epidemiology ; Male ; Prevalence ; Seasons ; *Symbiosis ; },
abstract = {This study was conducted to determine the prevalence of pathogenic and endosymbiont apicomplexans in the cat flea, Ctenocephalides felis (Bouché) infesting 185 stray cats in Jerusalem, Israel using PCR assay and sequencing approach. Two pathogens, Hepatozoon felis and Babesia vogeli and an endosymbiont Steinina ctenocephali were detected in 1.9%, 0.2% and 5.8% of 685 C. felis evaluated respectively. There was a significant association (p < 0.05) between the prevalence of H. felis and the sex of cats hosting the fleas as well as the season of sampling but not for age or health status of the cats or sex of the fleas tested. Prevalence of S. ctenocephali was significantly (p < 0.001) associated with season, being higher in the warm season. This report represents the first molecular detection of S. ctenocephali in C. felis. Further studies to determine the potential role of C. felis in the epidemiology of H. felis and B. vogeli are warranted.},
}
@article {pmid30013521,
year = {2018},
author = {Recchia, GH and Konzen, ER and Cassieri, F and Caldas, DGG and Tsai, SM},
title = {Arbuscular Mycorrhizal Symbiosis Leads to Differential Regulation of Drought-Responsive Genes in Tissue-Specific Root Cells of Common Bean.},
journal = {Frontiers in microbiology},
volume = {9},
number = {},
pages = {1339},
doi = {10.3389/fmicb.2018.01339},
pmid = {30013521},
issn = {1664-302X},
abstract = {Arbuscular mycorrhizal fungi (AMF) colonization in plants promotes both local and systemic changes in the gene expression profiles of the host that might be relevant for drought-stress perception and response. Drought-tolerant common bean plants (cv. BAT 477), colonized by a mixture of AMF (Glomus clarum, Acaulospora scrobiculata, and Gigaspora rosea), were exposed to a water deprivation regime of 96 h during pre-flowering. Root transcriptomes were accessed through RNA-Seq revealing a set of 9,965 transcripts with significant differential regulation in inoculated plants during a water deficit event, and 10,569 in non-inoculated. These data include 1,589 transcripts that are exclusively regulated by AMF-inoculation, and 2,313 under non-inoculation conditions. Relative gene expression analyses of nine aquaporin-related transcripts were performed in roots and leaves of plants harvested at initial stages of treatment. Significant shifts in gene expression were detected in AM water deficit-treated roots, in relation to non-inoculated, between 48 and 72 h. Leaves also showed significant mycorrhizal influence in gene expression, especially after 96 h. Root cortical cells, harboring or not arbuscules, were collected from both inoculation treatments through a laser microdissection-based technique. This allowed the identification of transcripts, such as the aquaporin PvPIP2;3 and Glucan 1,3 β-Glucosidase, that are unique to arbuscule-containing cells. During the water deficit treatment, AMF colonization exerted a fine-tune regulation in the expression of genes in the host. That seemed to initiate in arbuscule-containing cells and, as the stressful condition persisted, propagated to the whole-plant through secondary signaling events. Collectively, these results demonstrate that arbuscular mycorrhization leads to shifts in common bean's transcriptome that could potentially impact its adaptation capacity during water deficit events.},
}
@article {pmid30013185,
year = {2018},
author = {Feijen, FAA and Vos, RA and Nuytinck, J and Merckx, VSFT},
title = {Evolutionary dynamics of mycorrhizal symbiosis in land plant diversification.},
journal = {Scientific reports},
volume = {8},
number = {1},
pages = {10698},
doi = {10.1038/s41598-018-28920-x},
pmid = {30013185},
issn = {2045-2322},
abstract = {Mycorrhizal symbiosis between soil fungi and land plants is one of the most widespread and ecologically important mutualisms on earth. It has long been hypothesized that the Glomeromycotina, the mycorrhizal symbionts of the majority of plants, facilitated colonization of land by plants in the Ordovician. This view was recently challenged by the discovery of mycorrhiza-like associations with Mucoromycotina in several early diverging lineages of land plants. Utilizing a large, species-level database of plants' mycorrhiza-like associations and a Bayesian approach to state transition dynamics we here show that the recruitment of Mucoromycotina is the best supported transition from a non-mycorrhizal state. We further found that transitions between different combinations of either or both of Mucoromycotina and Glomeromycotina occur at high rates, and found similar promiscuity among combinations that include either or both of Glomeromycotina and Ascomycota with a nearly fixed association with Basidiomycota. Our results portray an evolutionary scenario of evolution of mycorrhizal symbiosis with a prominent role for Mucoromycotina in the early stages of land plant diversification.},
}
@article {pmid30010524,
year = {2018},
author = {Nouioui, I and Ghodhbane-Gtari, F and Rhode, M and Sangal, V and Klenk, HP and Gtari, M},
title = {Frankia irregularis sp. nov., an actinobacterium unable to nodulate its original host, Casuarina equisetifolia, but effectively nodulates members of the actinorhizal Rhamnales.},
journal = {International journal of systematic and evolutionary microbiology},
volume = {68},
number = {9},
pages = {2883-2914},
doi = {10.1099/ijsem.0.002914},
pmid = {30010524},
issn = {1466-5034},
mesh = {Bacterial Typing Techniques ; Base Composition ; Cell Wall/chemistry ; DNA, Bacterial/genetics ; Diaminopimelic Acid/chemistry ; Fatty Acids/chemistry ; Frankia/*classification/genetics/isolation &amp; purification ; Guadeloupe ; Magnoliopsida/*microbiology ; Nucleic Acid Hybridization ; Peptidoglycan/chemistry ; Phospholipids/chemistry ; *Phylogeny ; Pigmentation ; *Plant Root Nodulation ; RNA, Ribosomal, 16S/genetics ; Sequence Analysis, DNA ; Symbiosis ; Vitamin K 2/analogs &amp; derivatives/chemistry ; },
abstract = {A red pigmented actinobacterium designated G2T, forming extremely branched vegetative hyphae, vesicles and mutilocular sporangia, was isolated from Casuarina equisetifolia nodules. The strain failed to nodulate its original host plant but effectively nodulated members of actinorhizal Rhamnales. The taxonomic position of G2T was determined using a polyphasic approach. The peptidoglycan of the strain contained meso-diaminopimelic acid as diagnostic diamino acid, galactose, glucose, mannose, rhamnose, ribose and xylose. The polar lipid pattern consisted of phosphatidylinositol (PI), diphosphatidylglycerol (DPG), glycophospholipids (GPL1-2), phosphatidylglycerol (PG), aminophospholipid (APL) and unknown lipids (L). The predominant menaquinones were MK-9 (H4) and MK-9 (H6) while the major fatty acids were iso-C16 : 0, C17 : 1ω8c and C15 : 0. The size of the genome of G2T was 9.5 Mb and digital DNA G+C content was 70.9 %. The 16S rRNA gene showed 97.4-99.5 % sequence identity with the type strains of species of the genus Frankia. Digital DNA -DNA hybridisation (dDDH) values between G2T and its nearest phylogenetic neighbours Frankia elaeagniand Frankia discariaewere below the threshold of 70 %. On the basis of these results, strain G2T (=DSM 45899T=CECT 9038T) is proposed to represent the type strain of a novel species Frankia irregularis sp. nov.},
}
@article {pmid30008729,
year = {2018},
author = {Torres, N and Antolín, MC and Goicoechea, N},
title = {Arbuscular Mycorrhizal Symbiosis as a Promising Resource for Improving Berry Quality in Grapevines Under Changing Environments.},
journal = {Frontiers in plant science},
volume = {9},
number = {},
pages = {897},
doi = {10.3389/fpls.2018.00897},
pmid = {30008729},
issn = {1664-462X},
abstract = {Climate change and their resulting impacts are becoming a concern for winegrowers due to the high socioeconomic relevance of the winemaking sector worldwide. In fact, the projected climate change is expected to have detrimental impacts on the yield of grapevines, as well as on the quality and properties of grapes and wine. It is well known that arbuscular mycorrhizal fungi (AMF) can improve the nutritional quality of edible parts of crops and play essential roles in the maintenance of host plant fitness under stressed environments, including grapevines. The future scenarios of climate change may also modify the diversity and the growth of AMF in soils as well as the functionality of the mycorrhizal symbiosis. In this review, we summarize recent research progress on the effects of climate change on grapevine metabolism, paying special attention to the secondary compounds involved in the organoleptic properties of grapes and wines and to the levels of the phytohormones implied in the control of berry development and fruit ripening. In this context, the potential role of AMF for maintaining fruit quality in future climate change scenarios is discussed.},
}
@article {pmid30008590,
year = {2018},
author = {Park, MK and Kang, YJ and Jo, JO and Baek, KW and Yu, HS and Choi, YH and Cha, HJ and Ock, MS},
title = {Effect of Muscle Strength by Trichinella spiralis Infection during Chronic Phase.},
journal = {International journal of medical sciences},
volume = {15},
number = {8},
pages = {802-807},
doi = {10.7150/ijms.23497},
pmid = {30008590},
issn = {1449-1907},
abstract = {Introduction:Trichinella spiralis establishes a chronic infection in skeletal muscle by developing nurse cells within muscle fibers. During symbiosis in host, changes in the muscle fibers and inflammation may affect muscle function. Methods: We investigated muscle strength and inflammation in T. spiralis-infected mice during 1 to 48 weeks after infection. Results: Muscle strength decreased compared to that in uninfected control mice during the late infection stage. Additionally, inflammatory related cytokines increased significantly during early stage of infection and then rapidly decreased. In pathological study, nuclear infiltration maintained from the early infection stage to chronic infection stage. Moreover, vacuoles and eosinophil infiltration were observed in infected muscle in chronic stage. Conclusion: These results suggest that infection by T. spiralis significantly affects muscle function was continuously being weakness because vacuoles formation and maintained nucleus and eosinophil infiltration during chronic phase of T. spiralis infection.},
}
@article {pmid30008290,
year = {2018},
author = {Martino, ME and Joncour, P and Leenay, R and Gervais, H and Shah, M and Hughes, S and Gillet, B and Beisel, C and Leulier, F},
title = {Bacterial Adaptation to the Host's Diet Is a Key Evolutionary Force Shaping Drosophila-Lactobacillus Symbiosis.},
journal = {Cell host &amp; microbe},
volume = {24},
number = {1},
pages = {109-119.e6},
doi = {10.1016/j.chom.2018.06.001},
pmid = {30008290},
issn = {1934-6069},
support = {//European Research Council/International ; },
abstract = {Animal-microbe facultative symbioses play a fundamental role in ecosystem and organismal health. Yet, due to the flexible nature of their association, the selection pressures that act on animals and their facultative symbionts remain elusive. Here we apply experimental evolution to Drosophila melanogaster associated with its growth-promoting symbiont Lactobacillus plantarum, representing a well-established model of facultative symbiosis. We find that the diet of the host, rather than the host itself, is a predominant driving force in the evolution of this symbiosis. Furthermore, we identify a mechanism resulting from the bacterium's adaptation to the diet, which confers growth benefits to the colonized host. Our study reveals that bacterial adaptation to the host's diet may be the foremost step in determining the evolutionary course of a facultative animal-microbe symbiosis.},
}
@article {pmid30006910,
year = {2018},
author = {Symanczik, S and Lehmann, MF and Wiemken, A and Boller, T and Courty, PE},
title = {Effects of two contrasted arbuscular mycorrhizal fungal isolates on nutrient uptake by Sorghum bicolor under drought.},
journal = {Mycorrhiza},
volume = {},
number = {},
pages = {},
doi = {10.1007/s00572-018-0853-9},
pmid = {30006910},
issn = {1432-1890},
support = {PZ00P3_136651//Schweizerischer Nationalfonds zur Förderung der Wissenschaftlichen Forschung/ ; 127563//Schweizerischer Nationalfonds zur Förderung der Wissenschaftlichen Forschung/ ; 121258//Schweizerischer Nationalfonds zur Förderung der Wissenschaftlichen Forschung/ ; 130794//Schweizerischer Nationalfonds zur Förderung der Wissenschaftlichen Forschung/ ; },
abstract = {Drought is a limiting factor for crop production, especially in arid and semi-arid climates. In this study, Sorghum bicolor plants were inoculated, or not, with Rhizophagus irregularis, an arbuscular mycorrhizal (AM) strain typical for temperate climates, or Rhizophagus arabicus, a strain endemic to hyper-arid ecosystems. Plants were grown under well-watered or drought conditions in compartmented microcosms. Transpiration rates, plant growth, and nutrient uptake (using 15N as a tracer) were determined to assess the impact of drought stress on sorghum plants in AM symbiosis. Although AM colonization did not affect the bulk biomass of host plants, R. arabicus improved their transpiration efficiency and drought tolerance more than R. irregularis. Moreover, R. arabicus was able to extract more 15N from the soil under both water regimes, and AM-driven enhancement of the nitrogen and phosphorus content of sorghum, especially when water was limiting, was greater for R. arabicus-inoculated plants than for R. irregularis-inoculated plants. Our work demonstrates close links between AM hyphal phosphorus and nitrogen transport and uptake by AM plants for both AM fungal species. It also underscores that, under the drought stress conditions we applied, R. arabicus transfers significantly more nitrogen to sorghum than R. irregularis.},
}
@article {pmid30006562,
year = {2018},
author = {De Vita, P and Avio, L and Sbrana, C and Laidò, G and Marone, D and Mastrangelo, AM and Cattivelli, L and Giovannetti, M},
title = {Genetic markers associated to arbuscular mycorrhizal colonization in durum wheat.},
journal = {Scientific reports},
volume = {8},
number = {1},
pages = {10612},
doi = {10.1038/s41598-018-29020-6},
pmid = {30006562},
issn = {2045-2322},
abstract = {In this work we investigated the variability and the genetic basis of susceptibility to arbuscular mycorrhizal (AM) colonization of wheat roots. The mycorrhizal status of wild, domesticated and cultivated tetraploid wheat accessions, inoculated with the AM species Funneliformis mosseae, was evaluated. In addition, to detect genetic markers in linkage with chromosome regions involved in AM root colonization, a genome wide association analysis was carried out on 108 durum wheat varieties and two AM fungal species (F. mosseae and Rhizoglomus irregulare). Our findings showed that a century of breeding on durum wheat and the introgression of Reduced height (Rht) genes associated with increased grain yields did not select against AM symbiosis in durum wheat. Seven putative Quantitative Trait Loci (QTLs) linked with durum wheat mycorrhizal susceptibility in both experiments, located on chromosomes 1A, 2B, 5A, 6A, 7A and 7B, were detected. The individual QTL effects (r2) ranged from 7 to 16%, suggesting a genetic basis for this trait. Marker functional analysis identified predicted proteins with potential roles in host-parasite interactions, degradation of cellular proteins, homeostasis regulation, plant growth and disease/defence. The results of this work emphasize the potential for further enhancement of root colonization exploiting the genetic variability present in wheat.},
}
@article {pmid30006405,
year = {2018},
author = {Malmierca, MG and Pérez-Victoria, I and Martín, J and Reyes, F and Méndez, C and Olano, C and Salas, JA},
title = {Cooperative Involvement of Glycosyltransferases in the Transfer of Amino Sugars during the Biosynthesis of the Macrolactam Sipanmycin by Streptomyces sp. Strain CS149.},
journal = {Applied and environmental microbiology},
volume = {84},
number = {18},
pages = {},
doi = {10.1128/AEM.01462-18},
pmid = {30006405},
issn = {1098-5336},
abstract = {Macrolactams comprise a family of natural compounds with important bioactivities, such as antibiotic, antifungal, and antiproliferative activities. Sipanmycins A and B are two novel members of this family, with two sugar moieties attached to the aglycon. In the related macrolactam vicenistatin, the sugar moiety has been proven to be essential for cytotoxicity. In this work, the gene cluster responsible for the biosynthesis of sipanmycins (sip cluster) in Streptomyces sp. strain CS149 is described and the steps involved in the glycosylation of the final compounds unraveled. Also, the cooperation of two different glycosyltransferases in each glycosylation step is demonstrated. Additionally, the essential role of SipO2 as an auxiliary protein in the incorporation of the second deoxy sugar is addressed. In light of the results obtained by the generation of mutant strains and in silico characterization of the sip cluster, a biosynthetic pathway for sipanmycins and the two deoxy sugars attached is proposed. Finally, the importance of the hydroxyl group at C-10 of the macrolactam ring and the sugar moieties for cytotoxicity and antibiotic activity of sipanmycins is shown.IMPORTANCE The rapid emergence of infectious diseases and multiresistant pathogens has increased the necessity for new bioactive compounds; thus, novel strategies have to be developed to find them. Actinomycetes isolated in symbiosis with insects have attracted attention in recent years as producers of metabolites with important bioactivities. Sipanmycins are glycosylated macrolactams produced by Streptomyces sp. CS149, isolated from leaf-cutting ants, and show potent cytotoxic activity. Here, we characterize the sip cluster and propose a biosynthetic pathway for sipanmycins. As far as we know, it is the first time that the cooperation between two different glycosyltransferases is demonstrated to be strictly necessary for the incorporation of the same sugar. Also, a third protein with homology to P450 monooxygenases, SipO2, is shown to be essential in the second glycosylation step, forming a complex with the glycosyltransferase pair SipS9-SipS14.},
}
@article {pmid30005404,
year = {2018},
author = {Chen, J and Liu, YQ and Yan, XW and Wei, GH and Zhang, JH and Fang, LC},
title = {Rhizobium inoculation enhances copper tolerance by affecting copper uptake and regulating the ascorbate-glutathione cycle and phytochelatin biosynthesis-related gene expression in Medicago sativa seedlings.},
journal = {Ecotoxicology and environmental safety},
volume = {162},
number = {},
pages = {312-323},
doi = {10.1016/j.ecoenv.2018.07.001},
pmid = {30005404},
issn = {1090-2414},
mesh = {Ascorbic Acid/metabolism ; Biodegradation, Environmental ; Copper/*toxicity ; Gene Expression Regulation, Plant/drug effects ; Glutathione/metabolism ; Lipid Peroxidation/drug effects ; Medicago sativa/*drug effects/genetics/metabolism/microbiology ; Metallothionein/metabolism ; Phytochelatins/biosynthesis ; Plant Roots/drug effects/genetics/metabolism/microbiology ; Plant Shoots/drug effects/genetics/metabolism/microbiology ; Reactive Oxygen Species/metabolism ; Rhizobium/*metabolism ; Seedlings/drug effects/genetics/metabolism/microbiology ; Soil Pollutants/*toxicity ; Symbiosis ; },
abstract = {Despite numerous reports that legume-rhizobium symbiosis alleviates Cu stress in plants, the possible roles of legume-rhizobium symbiosis and the regulatory mechanisms in counteracting Cu toxicity remain unclear. Here, Sinorhizobium meliloti CCNWSX0020 was used for analyzing the effects of rhizobium inoculation on plant growth in Medicago sativa seedlings under Cu stress. Our results showed that rhizobium inoculation alleviated Cu-induced growth inhibition, and increased nitrogen concentration in M. sativa seedlings. Moreover, the total amount of Cu uptake in inoculated plants was significantly increased compared with non-inoculated plants, and the increase in the roots was much higher than that in the shoots, thus decreasing the transfer coefficient and promoting Cu phytostabilization. Cu stress induced lipid peroxidation and reactive oxygen species production, but rhizobium inoculation reduced these components' accumulation through altering antioxidant enzyme activities and regulating ascorbate-glutathione cycles. Furthermore, legume-rhizobium symbiosis regulated the gene expression involved in antioxidant responses, phytochelatin (PC) biosynthesis, and metallothionein biosynthesis in M. sativa seedlings under Cu stress. Our results demonstrate that rhizobium inoculation enhanced Cu tolerance by affecting Cu uptake, regulating antioxidant enzyme activities and the ascorbate-glutathione cycle, and influencing PC biosynthesis-related gene expression in M. sativa. The results provide an efficient strategy for phytoremediation of Cu-contaminated soils.},
}
@article {pmid30003907,
year = {2018},
author = {Jiménez-Cortés, JG and García-Contreras, R and Bucio-Torres, MI and Cabrera-Bravo, M and Córdoba-Aguilar, A and Benelli, G and Salazar-Schettino, PM},
title = {Bacterial symbionts in human blood-feeding arthropods: Patterns, general mechanisms and effects of global ecological changes.},
journal = {Acta tropica},
volume = {186},
number = {},
pages = {69-101},
doi = {10.1016/j.actatropica.2018.07.005},
pmid = {30003907},
issn = {1873-6254},
abstract = {Due to their high impact on public health, human blood-feeding arthropods are one of the most relevant animal groups. Bacterial symbionts have been long known to play a role in the metabolism, and reproduction of these arthropod vectors. Nowadays, we have a more complete picture of their functions, acknowledging the wide influence of bacterial symbionts on processes ranging from the immune response of the arthropod host to the possible establishment of pathogens and parasites. One or two primary symbiont species have been found to co-evolve along with their host in each taxon (being ticks an exception), leading to various kinds of symbiosis, mostly mutualistic in nature. Moreover, several secondary symbiont species are shared by all arthropod groups. With respect to gut microbiota, several bacterial symbionts genera are hosted in common, indicating that these bacterial groups are prone to invade several hematophagous arthropod species feeding on humans. The main mechanisms underlying bacterium-arthropod symbiosis are discussed, highlighting that even primary symbionts elicit an immune response from the host. Bacterial groups in the gut microbiota play a key role in immune homeostasis, and in some cases symbiont bacteria could be competing directly or indirectly with pathogens and parasites. Finally, the effects climate change, great human migrations, and the increasingly frequent interactions of wild and domestic animal species are analyzed, along with their implications on microbiota alteration and their possible impacts on public health and the control of pathogens and parasites harbored in arthropod vectors of human parasites and pathogens.},
}
@article {pmid30002670,
year = {2018},
author = {Benckiser, G and Hartmann, A and Kumar, K and Honermeier, B},
title = {Editorial: Plant-Microbe-Insect Interaction: Source for Bio-fertilizers, Bio-medicines and Agent Research.},
journal = {Frontiers in plant science},
volume = {9},
number = {},
pages = {931},
doi = {10.3389/fpls.2018.00931},
pmid = {30002670},
issn = {1664-462X},
}
@article {pmid30001518,
year = {2018},
author = {Garrido-Oter, R and Nakano, RT and Dombrowski, N and Ma, KW and , and McHardy, AC and Schulze-Lefert, P},
title = {Modular Traits of the Rhizobiales Root Microbiota and Their Evolutionary Relationship with Symbiotic Rhizobia.},
journal = {Cell host &amp; microbe},
volume = {24},
number = {1},
pages = {155-167.e5},
doi = {10.1016/j.chom.2018.06.006},
pmid = {30001518},
issn = {1934-6069},
support = {//European Research Council/International ; },
abstract = {Rhizobia are a paraphyletic group of soil-borne bacteria that induce nodule organogenesis in legume roots and fix atmospheric nitrogen for plant growth. In non-leguminous plants, species from the Rhizobiales order define a core lineage of the plant microbiota, suggesting additional functional interactions with plant hosts. In this work, genome analyses of 1,314 Rhizobiales isolates along with amplicon studies of the root microbiota reveal the evolutionary history of nitrogen-fixing symbiosis in this bacterial order. Key symbiosis genes were acquired multiple times, and the most recent common ancestor could colonize roots of a broad host range. In addition, root growth promotion is a characteristic trait of Rhizobiales in Arabidopsis thaliana, whereas interference with plant immunity constitutes a separate, strain-specific phenotype of root commensal Alphaproteobacteria. Additional studies with a tripartite gnotobiotic plant system reveal that these traits operate in a modular fashion and thus might be relevant to microbial homeostasis in healthy roots.},
}
@article {pmid30001516,
year = {2018},
author = {Ferretti, P and Pasolli, E and Tett, A and Asnicar, F and Gorfer, V and Fedi, S and Armanini, F and Truong, DT and Manara, S and Zolfo, M and Beghini, F and Bertorelli, R and De Sanctis, V and Bariletti, I and Canto, R and Clementi, R and Cologna, M and Crifò, T and Cusumano, G and Gottardi, S and Innamorati, C and Masè, C and Postai, D and Savoi, D and Duranti, S and Lugli, GA and Mancabelli, L and Turroni, F and Ferrario, C and Milani, C and Mangifesta, M and Anzalone, R and Viappiani, A and Yassour, M and Vlamakis, H and Xavier, R and Collado, CM and Koren, O and Tateo, S and Soffiati, M and Pedrotti, A and Ventura, M and Huttenhower, C and Bork, P and Segata, N},
title = {Mother-to-Infant Microbial Transmission from Different Body Sites Shapes the Developing Infant Gut Microbiome.},
journal = {Cell host &amp; microbe},
volume = {24},
number = {1},
pages = {133-145.e5},
doi = {10.1016/j.chom.2018.06.005},
pmid = {30001516},
issn = {1934-6069},
support = {//European Research Council/International ; },
abstract = {The acquisition and development of the infant microbiome are key to establishing a healthy host-microbiome symbiosis. The maternal microbial reservoir is thought to play a crucial role in this process. However, the source and transmission routes of the infant pioneering microbes are poorly understood. To address this, we longitudinally sampled the microbiome of 25 mother-infant pairs across multiple body sites from birth up to 4 months postpartum. Strain-level metagenomic profiling showed a rapid influx of microbes at birth followed by strong selection during the first few days of life. Maternal skin and vaginal strains colonize only transiently, and the infant continues to acquire microbes from distinct maternal sources after birth. Maternal gut strains proved more persistent in the infant gut and ecologically better adapted than those acquired from other sources. Together, these data describe the mother-to-infant microbiome transmission routes that are integral in the development of the infant microbiome.},
}
@article {pmid30001470,
year = {2018},
author = {Lu, J and Magain, N and Miadlikowska, J and Coyle, JR and Truong, C and Lutzoni, F},
title = {Bioclimatic factors at an intrabiome scale are more limiting than cyanobiont availability for the lichen-forming genus Peltigera.},
journal = {American journal of botany},
volume = {105},
number = {7},
pages = {1198-1211},
doi = {10.1002/ajb2.1119},
pmid = {30001470},
issn = {1537-2197},
abstract = {PREMISE OF THE STUDY: Factors shaping spatiotemporal patterns of associations in mutualistic systems are poorly understood. We used the lichen-forming fungi Peltigera and their cyanobacterial partners Nostoc to investigate the spatial structure of this symbiosis at an intrabiome scale and to identify potential factors shaping these associations.<br><br>METHODS: Ninety-three thalli were sampled in Québec, Canada, along a south-north and an east-west transect of ~1300 km each. We identified the two main partners (Peltigera species and Nostoc phylogroups) using molecular markers and modeled the effects of environmental variables and partner occurrence on Peltigera-Nostoc distributions.<br><br>KEY RESULTS: Peltigera species showed a high degree of specialization toward cyanobionts, whereas two Nostoc phylogroups dominated both transects by associating with several Peltigera species. Peltigera species had narrower ranges than these two main cyanobionts. Distributions of three Peltigera species were highly associated with precipitation and temperature variables, which was not detected for Nostoc phylogroups at this spatial scale.<br><br>CONCLUSIONS: For these cyanolichens, factors driving patterns of symbiotic associations are scale dependent. Contrary to global-scale findings, generalist Peltigera species were not more widespread within the boreal biome than specialists. Nostoc availability was not the only driver of Peltigera species' geographic ranges; environmental factors also contributed to their intrabiome distributions. Climatic conditions (especially precipitation) limited the range of some Peltigera species more than the range of their cyanobacterial partners at an intrabiome (boreal) scale.},
}
@article {pmid30001166,
year = {2018},
author = {Lenting, K and Khurshed, M and Peeters, TH and van den Heuvel, CNAM and van Lith, SAM and de Bitter, T and Hendriks, W and Span, PN and Molenaar, RJ and Botman, D and Verrijp, K and Heerschap, A and Ter Laan, M and Kusters, B and van Ewijk, A and Huynen, MA and van Noorden, CJF and Leenders, WPJ},
title = {Isocitrate dehydrogenase 1-mutated human gliomas depend on lactate and glutamate to alleviate metabolic stress.},
journal = {FASEB journal : official publication of the Federation of American Societies for Experimental Biology},
volume = {},
number = {},
pages = {fj201800907RR},
doi = {10.1096/fj.201800907RR},
pmid = {30001166},
issn = {1530-6860},
abstract = {Diffuse gliomas often carry point mutations in isocitrate dehydrogenase (IDH1mut), resulting in metabolic stress. Although IDHmut gliomas are difficult to culture in vitro, they thrive in the brain via diffuse infiltration, suggesting brain-specific tumor-stroma interactions that can compensate for IDH-1 deficits. To elucidate the metabolic adjustments in clinical IDHmut gliomas that contribute to their malignancy, we applied a recently developed method of targeted quantitative RNA next-generation sequencing to 66 clinical gliomas and relevant orthotopic glioma xenografts, with and without the endogenous IDH-1R132H mutation. Datasets were analyzed in R using Manhattan plots to calculate distance between expression profiles, Ward's method to perform unsupervised agglomerative clustering, and the Mann Whitney U test and Fisher's exact tests for supervised group analyses. The significance of transcriptome data was investigated by protein analysis, in situ enzymatic activity mapping, and in vivo magnetic resonance spectroscopy of orthotopic IDH1mut- and IDHwt-glioma xenografts. Gene set enrichment analyses of clinical IDH1mut gliomas strongly suggest a role for catabolism of lactate and the neurotransmitter glutamate, whereas, in IDHwt gliomas, processing of glucose and glutamine are the predominant metabolic pathways. Further evidence of the differential metabolic activity in these cancers comes from in situ enzymatic mapping studies and preclinical in vivo magnetic resonance spectroscopy imaging. Our data support an evolutionary model in which IDHmut glioma cells exist in symbiosis with supportive neuronal cells and astrocytes as suppliers of glutamate and lactate, possibly explaining the diffuse nature of these cancers. The dependency on glutamate and lactate opens the way for novel approaches in the treatment of IDHmut gliomas.-Lenting, K., Khurshed, M., Peeters, T. H., van den Heuvel, C. N. A. M., van Lith, S. A. M., de Bitter, T., Hendriks, W., Span, P. N., Molenaar, R. J., Botman, D., Verrijp, K., Heerschap, A., ter Laan, M., Kusters, B., van Ewijk, A., Huynen, M. A., van Noorden, C. J. F., Leenders, W. P. J. Isocitrate dehydrogenase 1-mutated human gliomas depend on lactate and glutamate to alleviate metabolic stress.},
}
@article {pmid29998535,
year = {2018},
author = {},
title = {Corrigendum.},
journal = {The New phytologist},
volume = {219},
number = {3},
pages = {1134},
doi = {10.1111/nph.15242},
pmid = {29998535},
issn = {1469-8137},
}
@article {pmid29997418,
year = {2018},
author = {Gyogluu, C and Mohammed, M and Jaiswal, SK and Kyei-Boahen, S and Dakora, FD},
title = {Assessing host range, symbiotic effectiveness, and photosynthetic rates induced by native soybean rhizobia isolated from Mozambican and South African soils.},
journal = {Symbiosis (Philadelphia, Pa.)},
volume = {75},
number = {3},
pages = {257-266},
doi = {10.1007/s13199-017-0520-5},
pmid = {29997418},
issn = {0334-5114},
abstract = {Host range and cross-infectivity studies are important for identifying rhizobial strains with potential for use as inoculants. In this study, 10 native soybean rhizobia isolated from Mozambican and South African soils were evaluated for host range, symbiotic effectiveness and ability to induce high rates of photosynthesis leading to enhanced plant growth in cowpea (Vigna unguiculata L. Walp.), Bambara groundnut (Vigna subterranean L. Verdc.), Kersting's groundnut (Macrotyloma geocarpum Harm) and soybean (Glycine max L. Merr). The test isolates had different growth rates and colony sizes. Molecular analysis based on enterobacterial repetitive intergenic consensus (ERIC)-PCR revealed high genetic diversity among the test isolates. The results further showed that isolate TUTLBC2B failed to elicit nodulation in all test plants, just as TUTNSN2A and TUTDAIAP3B were also unable to nodulate cowpea, Kersting's bean and Bambara groundnut. Although the remaining strains formed ineffective nodules on cowpea and Kersting's bean, they induced effective nodules on Bambara groundnut and the two soybean genotypes. Bacterial stimulation of nodule numbers, nodule dry weights and photosynthetic rates was generally greater with isolates TUTRSRH3A, TUTM19373A, TUTMCJ7B, TUTRLR3B and TUTRJN5A. As a result, these isolates elicited significantly increased accumulation of biomass in shoots and whole plants of Bambara groundnut and the two soybean genotypes. Whole-plant symbiotic nitrogen (N) of soybean and Bambara groundnut was highest for the commercial strains CB756 and WB74, as well as for TUTRLR3B, TUTMCJ7B and TUTRSRH3A, suggesting that the three native rhizobial isolates have potential for use as inoculants.},
}
@article {pmid29997417,
year = {2018},
author = {Samago, TY and Anniye, EW and Dakora, FD},
title = {Grain yield of common bean (Phaseolus vulgaris L.) varieties is markedly increased by rhizobial inoculation and phosphorus application in Ethiopia.},
journal = {Symbiosis (Philadelphia, Pa.)},
volume = {75},
number = {3},
pages = {245-255},
doi = {10.1007/s13199-017-0529-9},
pmid = {29997417},
issn = {0334-5114},
abstract = {A field experiment was conducted to assess plant growth, symbiotic performance and grain yield of common bean in response to rhizobial incoculation and phosphorus application at Galalicha in Southern Ethiopia during the 2012 and 2013 cropping seasons under rain-fed conditions. The treatments consisted of 2 released common bean varieties (Hawassa Dume and Ibbado), 3 levels of Rhizobium inoculation (uninoculated, inoculated with strain HB-429 or GT-9) and 4 levels of phosphorus application (0, 10, 20 and 30 kg P ha-1) using a split-split plot design with four replications. Here, phosphorus levels, Rhizobium inoculation and common bean varieties were assigned as main, sub- and sub-sub treatments, respectively. The results revealed marked varietal differences in plant growth, grain yield and symbiotic performance. Of the two common bean varieties studied, Hawassa Dume generally showed superior performance in most measured parameters in 2013. Rhizobium inoculation significantly (p ≤ 0.05) increased plant growth, symbiotic performance and grain yield. Applying Rhizobium strain HB-429 to bean crop respectively increased plant growth, %Ndfa, amount of N-fixed and grain yield by 19, 17, 54 and 48% over uninoculated control. Similarly, the application of 20 kg P ha-1 to bean plants respectively resulted in 36, 20, 96 and 143% increase in plant growth, %Ndfa, N-fixed and grain yield when compared to the control. These results clearly indicate that plant growth, symbiotic performance and grain yield of common bean can be significantly increased by Rhizobium inoculation and phosphorus fertilization in Ethiopia. Rhizobium inoculants are a cheaper source of nitrogen than chemical fertilizers and when combined with moderate phosphorus application can markedly increase grain yield for resource-poor farmers.},
}
@article {pmid29997416,
year = {2018},
author = {Oteng-Frimpong, R and Dakora, FD},
title = {Selecting elite groundnut (Arachis hypogaea L) genotypes for symbiotic N nutrition, water-use efficiency and pod yield at three field sites, using 15N and 13C natural abundance.},
journal = {Symbiosis (Philadelphia, Pa.)},
volume = {75},
number = {3},
pages = {229-243},
doi = {10.1007/s13199-017-0524-1},
pmid = {29997416},
issn = {0334-5114},
abstract = {About 70% of the groundnut (Arachis hypogaea L.) produced in Ghana is from the Guinea savanna. However, low soil nutrients, especially N, together with erratic rainfall distribution have often resulted in poor grain yield. The aim of this study was to evaluate plant growth, N2-fixing efficiency, N contribution, water-use efficiency and pod yield of 21 elite groundnut genotypes in the Guinea savanna of Ghana, using the 15N natural abundance technique. The data revealed significant variations in plant growth, symbiotic N contribution, and pod yield among the 21 genotypes tested at each field site. Average N contribution by groundnut genotypes ranged from 48 to 108 kg N ha-1. Also, mean pod yield ranged from 0.58 to 2.1 t ha-1. Genotypes ICGV-IS 08837, ICG 6222, ICGV 03315 and NKATIESARI demonstrated superior plant growth, symbiotic N contribution and greater pod yield. In fact, ICGV-IS 08837 yielded almost 2.5 fold more than CHINESE which is the most widely cultivated variety in the region. Genotypes ICGV-IS 08837, ICG 6222, ICGV 03315 and ICGV 99247 are therefore recommended for development into varieties for the Guinea savanna of Ghana. Genotypes ICG (FDRS) 4, ICGV00362 and ICGV99247 exhibited increased water-use efficiency, but were low in N2 fixation and N contribution, and would therefore be good parental material in breeding programs aimed at enhancing water-use efficiency in high N2-fixing genotypes.},
}
@article {pmid29997415,
year = {2018},
author = {Mbah, GC and Dakora, FD},
title = {Nitrate inhibition of N2 fixation and its effect on micronutrient accumulation in shoots of soybean (Glycine max L. Merr.), Bambara groundnut (Vigna subterranea L. Vedc) and Kersting's groundnut (Macrotyloma geocarpum Harms.).},
journal = {Symbiosis (Philadelphia, Pa.)},
volume = {75},
number = {3},
pages = {205-216},
doi = {10.1007/s13199-017-0531-2},
pmid = {29997415},
issn = {0334-5114},
abstract = {Although nitrate is known to inhibit nodulation and N2 fixation in symbiotic legumes, little is known about its effect on the uptake and accumulation of trace elements such as Fe, Zn, Mn and Cu. The aim of this study was to evaluate the effect of 5 mM NO3- supply, either with or without rhizobial inoculation, on nodulation, nodule functioning and micronutrient levels in the shoots of soybean (Glycine max L.Merr.), Bambara groundnut (Vigna subterranea L. Vedc) and Kersting's groundnut (Macrotyloma geocarpum Harm). The results showed reduction in plant growth, nodule formation and nodule dry matter by the supply of 5 mM NO3- to inoculated seedlings of all three species. Nitrate inhibition respectively caused 1.2, 1.4, and 1.5-fold decrease in nodule number per plant in Bambara groundnut, soybean and Kersting's bean, which resulted in 2.3, 3.3 and 4.5-fold reduction in nodule dry weight of the test species (in that order). The application of 5 mM NO3- to soybean plants also resulted in 2.5, 4.0 and 5.4-fold decrease in shoot accumulation of Fe, Zn and Mn, respectively, when compared to the purely symbiotic control plants. Furthermore, we observed 1.3, 1.8 and 1.3-fold decreases in the concentration of Zn, Mn and Cu in shoots of inoculated Bambara groundnut with NO3- supply, levels lower than those found in soybean. With Kersting's groundnut, shoot concentration of Fe, Zn and Cu were higher with the application of 5 mM NO3- to inoculated plants when compared to the purely symbiotic treatment, which was opposite to soybean. But pure NO3-feeding of this species respectively resulted in 2.0, 1.4 and 1.3-fold decreases in Fe, Zn and Cu relative to inoculated NO3--fed plants. Clearly, NO3- supply to landraces/genotypes of the three legume species did not only inhibit nodule formation and functioning, it also reduced shoot micronutrient levels in soybean and Bambara groundnut, but not Kersting's bean.},
}
@article {pmid29997414,
year = {2018},
author = {Beyan, SM and Wolde-Meskel, E and Dakora, FD},
title = {An assessment of plant growth and N2 fixation in soybean genotypes grown in uninoculated soils collected from different locations in Ethiopia.},
journal = {Symbiosis (Philadelphia, Pa.)},
volume = {75},
number = {3},
pages = {189-203},
doi = {10.1007/s13199-018-0540-9},
pmid = {29997414},
issn = {0334-5114},
abstract = {Achieving food and nutritional security is a major challenge in Ethiopia, especially with increasing human population and low crop productivity. Legumes offer an alternative choice to chemical fertilizers for increasing crop yields. The aim of this study was to assess, under glasshouse conditions, plant growth and symbiotic performance of uninoculated soybean genotypes planted in soils collected from different locations in Ethiopia. The results showed significant differences in plant growth and symbiotic performance among the soybean genotypes planted in different soils. There was a location-specific effect of soil on plant growth and symbiotic N nutrition of soybean. Whole-plant biomass was highest in soil from Amaro, followed by Boricha, Dorebafano, Pawe, and Mambuk. The δ15N values ranged from +0.82‰ for Pawe to +5.11‰ at Dorebafano. However, %Ndfa of soybean was greater in plants grown in Mambuk soil, followed by Pawe with the lowest %Ndfa being in Amaro soil. The amount of N-fixed followed similar pattern as %Ndfa. The significant interaction found between soil type and soybean genotype for plant DM, shoot N concentration, δ15N, %Ndfa, N-fixed and soil N-uptake clearly indicated the effect of soil factors. This study revealed the presence of native rhizobia in Ethiopian soils that are compatible with soybean. The N contribution of the soybean genotypes was variable, and strongly influenced by the soil factors.},
}
@article {pmid29997413,
year = {2018},
author = {Bernard, N and Losologolo, M and Batlang, U and Ngwako, S and Mashungwa, GN and Tselaesele, NM and Pule-Meulenberg, F},
title = {Symbiotic performance of grain and wild herbaceous legumes in the Okavango Delta and Tswapong region of Botswana.},
journal = {Symbiosis (Philadelphia, Pa.)},
volume = {75},
number = {3},
pages = {179-188},
doi = {10.1007/s13199-017-0515-2},
pmid = {29997413},
issn = {0334-5114},
abstract = {The low inherent soil fertility, especially nitrogen (N) constrains arable agriculture in Botswana. Nitrogen is usually added to soil through inorganic fertilizer application. In this study, biological nitrogen fixation by legumes is explored as an alternative source of N. The objectives of this study were to measure levels of N2 fixation by grain legumes such as cowpea, Bambara groundnut and groundnut in farmers' fields as well as to estimated N2 fixation by indigenous herbaceous legumes growing in the Okavango Delta. Four flowering plants per species were sampled from the panhandle part of the Okavango Delta and Tswapong area. Nitrogen fixation was measured using the 15N stable isotope natural abundance technique. The δ15N values of indigenous herbaceous legumes indicated that they fixed N2 (-1.88 to +1.35 ‰) with the lowest value measured in Chamaecrista absus growing in Ngarange (Okavango Delta). The δ15N values of grain legumes growing on farmers' fields ranging from -1.2 ‰ to +3.3 ‰ indicated that they were fixing N2. For grain legumes growing at most farms, %Ndfa were above 50% indicating that they largely depended on symbiotic fixation for their N nutrition. With optimal planting density, Bambara groundnuts on farmers' fields could potentially fix over 90 kg N/ha in some parts of Tswapong area and about 60 kg N/ha in areas around the Okavango Delta. Results from this study have shown that herbaceous indigenous legumes and cultivated legumes play an important role in the cycling of N in the soil. It has also been shown that biological N2 on farmer's field could potentially supply the much needed N for the legumes and the subsequent cereal crops if plant densities are optimized with the potential to increase food security and mitigate climate change.},
}
@article {pmid29997412,
year = {2018},
author = {Bello, SK and Yusuf, AA and Cargele, M},
title = {Performance of cowpea as influenced by native strain of rhizobia, lime and phosphorus in Samaru, Nigeria.},
journal = {Symbiosis (Philadelphia, Pa.)},
volume = {75},
number = {3},
pages = {167-176},
doi = {10.1007/s13199-017-0507-2},
pmid = {29997412},
issn = {0334-5114},
abstract = {The complimentary effects of a native rhizobia strain (SAMFIX 286), lime and single superphosphate (SSP) as components of ISFM were evaluated on the biomass, nodulation and N2 fixation of cowpea (Vigna unguiculata L.). Lime was applied at the rate of 250 kg (Ca(OH)2) ha-1, while SSP was applied at 30 kg P ha-1. The trial was carried out in a screen house with the treatments arranged in randomized complete block design. Results obtained show that the performance of SAMFIX 286 inoculated plants did not significantly (p < 0.05) differ from that of the un-inoculated treatment. Application of lime significantly increased root dry weight, shoot dry weight, nodule number and dry weight by 42.5%, 35.3%, 65.6% and 50%, respectively. Nodulation was significantly (p < 0.05) increased by SSP. The complimentary effect of lime with SSP significantly increased total shoot N concentration. Similarly, combined inoculation of SAMFIX 286 with lime and SSP increased N concentration by 31.9% and N derived from atmosphere (Ndfa) by 16.3% compared to the un-inoculated treatment. Inoculation of SAMFIX 286 with SSP was also effective on Ndfa by cowpea. It was concluded that lime and SSP were good combination with native rhizobia strain in improving cowpea nodulation and biological N2 fixation.},
}
@article {pmid29992244,
year = {2018},
author = {Cheng, H and Dove, NC and Mena, JM and Perez, T and Ul-Hasan, S},
title = {The Biota Project: A Case Study of a Multimedia, Grassroots Approach to Scientific Communication for Engaging Diverse Audiences.},
journal = {Integrative and comparative biology},
volume = {},
number = {},
pages = {},
doi = {10.1093/icb/icy091},
pmid = {29992244},
issn = {1557-7023},
abstract = {SYNOPSIS: The Biota Project communicates science to populations historically ignored by the scientific community. The Biota Project is comprised of a team of young professionals from a myriad of backgrounds and locations with interests in promoting science accessibility and equity. We do this by highlighting research conducted by scientists from underrepresented groups in relatable yet underrated locations with the intention of increasing the participation of underrepresented populations in science. The Biota Project centers on the scientific definition of symbiosis as a tool for both educating and learning from its followers. We deliver stories on the environments of our own backyards by merging art and science and distributing these publicly available stories widely online through short films, media clips, drawings, paintings, blogs, and e-newsletters. This project demonstrates a fresh, transferable perspective on strengthening science communication in a way that conjoins scientific discovery with social justice through the promotion of critical thinking by its target audience. Likewise, contributors learn how to better support local communities with each new story and environment. The Biota Project thus sets a symbiotic tone for re-calibrating the balance between academics, researchers, and local communities. When science is made relevant through understanding, its quality and significance are enhanced, and public recognition of its value is increased.},
}
@article {pmid29991760,
year = {2018},
author = {Lind, AE and Lewis, WH and Spang, A and Guy, L and Embley, TM and Ettema, TJG},
title = {Genomes of two archaeal endosymbionts show convergent adaptations to an intracellular lifestyle.},
journal = {The ISME journal},
volume = {12},
number = {11},
pages = {2655-2667},
doi = {10.1038/s41396-018-0207-9},
pmid = {29991760},
issn = {1751-7370},
support = {310039//EC | European Research Council (ERC)/ ; 20100317//EC | European Research Council (ERC)/ ; 621-2009-4813//Vetenskapsrådet (Swedish Research Council)/ ; SSF-FFL5//Stiftelsen för Strategisk Forskning (Swedish Foundation for Strategic Research)/ ; },
abstract = {Endosymbiosis is a widespread phenomenon in the microbial world and can be based on diverse interactions between endosymbiont and host cell. The vast majority of the known endosymbiotic interactions involve bacteria that have invaded eukaryotic host cells. However, methanogenic archaea have been found to thrive in anaerobic, hydrogenosome-containing protists and it was suggested that this symbiosis is based on the transfer of hydrogen. Here, we used culture-independent genomics approaches to sequence the genomes of two distantly related methanogenic endosymbionts that have been acquired in two independent events by closely related anaerobic ciliate hosts Nyctotherus ovalis and Metopus contortus, respectively. The sequences obtained were then validated as originating from the ciliate endosymbionts by in situ probing experiments. Comparative analyses of these genomes and their closest free-living counterparts reveal that the genomes of both endosymbionts are in an early stage of adaptation towards endosymbiosis as evidenced by the large number of genes undergoing pseudogenization. For instance, the observed loss of genes involved in amino acid biosynthesis in both endosymbiont genomes indicates that the endosymbionts rely on their hosts for obtaining several essential nutrients. Furthermore, the endosymbionts appear to have gained significant amounts of genes of potentially secreted proteins, providing targets for future studies aiming to elucidate possible mechanisms underpinning host-interactions. Altogether, our results provide the first genomic insights into prokaryotic endosymbioses from the archaeal domain of life.},
}
@article {pmid29990771,
year = {2018},
author = {Setsungnern, A and Treesubsuntorn, C and Thiravetyan, P},
title = {Chlorophytum comosum-bacteria interactions for airborne benzene remediation: Effect of native endophytic Enterobacter sp. EN2 inoculation and blue-red LED light.},
journal = {Plant physiology and biochemistry : PPB},
volume = {130},
number = {},
pages = {181-191},
doi = {10.1016/j.plaphy.2018.06.042},
pmid = {29990771},
issn = {1873-2690},
mesh = {Air Pollutants ; Asparagaceae/*microbiology/*radiation effects ; Benzene/*metabolism ; Biodegradation, Environmental ; Endophytes ; Enterobacter/*physiology/*radiation effects ; *Light ; Photosynthesis ; Stress, Physiological ; Symbiosis ; Time Factors ; },
abstract = {This study was performed to determine the effect of plant-endophytic Enterobacter sp. EN2 interactions and blue-red LED light conditions on gaseous benzene removal by plants. It was found that under consecutive benzene fumigation for three cycles (18 days), inoculation of the strain EN2 into sterilized and non-sterilized native C. comosum resulted in significantly increased gaseous benzene removal compared to that in non-inoculated groups under the same light conditions (P < 0.05). Remarkably, EN2 colonization in inoculated plants under LED conditions was higher than under fluorescence conditions as the EN2 could grow better under LED conditions. Strain EN2 possesses NADPH that is used to facilitate benzene degradation and modulate plant growth under benzene stress by bacterial IAA production and ACC deaminase activity; higher IAA and lower ethylene levels were found in inoculated plants compared to non-inoculated ones. These contributed to better benzene removal efficiency. Interestingly, under fumigation for 16 cycles (67 days), there was no difference in gaseous benzene removal between inoculated plants and non-inoculated plants under the same light conditions at initial benzene concentrations of 5 ppm. This is probably due to EN2 reaching maximum growth under all treatments. However, C. comosum exhibited better benzene removal under LED conditions than under fluorescence conditions during 16 cycles, possibly due to better photosynthetic performance and plant growth, leading to more NADPH, and eventually enhanced benzene removal efficiency. Hence, the most efficient acceleration of benzene removal was provided by inoculation of strain EN2 onto C. comosum under blue-red LED light conditions.},
}
@article {pmid29990724,
year = {2018},
author = {Noori, F and Etesami, H and Najafi Zarini, H and Khoshkholgh-Sima, NA and Hosseini Salekdeh, G and Alishahi, F},
title = {Mining alfalfa (Medicago sativa L.) nodules for salinity tolerant non-rhizobial bacteria to improve growth of alfalfa under salinity stress.},
journal = {Ecotoxicology and environmental safety},
volume = {162},
number = {},
pages = {129-138},
doi = {10.1016/j.ecoenv.2018.06.092},
pmid = {29990724},
issn = {1090-2414},
mesh = {Klebsiella/isolation &amp; purification ; Medicago sativa/*growth &amp; development/*microbiology ; Rhizobium/*isolation &amp; purification ; Root Nodules, Plant/*microbiology ; *Salinity ; Salt-Tolerance ; Sinorhizobium meliloti/isolation &amp; purification ; Soil/chemistry ; Soil Microbiology ; Stress, Physiological ; Symbiosis ; },
abstract = {There are fewer reports on plant growth promoting (PGP) bacteria living in nodules as helper to tolerance to abiotic stress such as salinity and drought. The study was conducted to isolate rhizobial and non-rhizobial drought and salinity tolerant bacteria from the surface sterilized root nodules of alfalfa, grown in saline soils, and evaluate the effects of effective isolates on plant growth under salt stress. Based on drought and salinity tolerance of bacterial isolates and having multiple PGP traits, two non-rhizobial endophytic isolates and one rhizobial endophytic isolate were selected for further identification and characterization. Based on partial sequences of 16 S rRNA genes, non-rhizobial isolates and rhizobial isolate were closely related to Klebsiella sp., Kosakonia cowanii, and Sinorhizobium meliloti, respectively. None of the two non-rhizobial strains were able to form nodules on alfalfa roots under greenhouse and in vitro conditions. Co-inoculation of alfalfa plant with Klebsiella sp. A36, K. cowanii A37, and rhizobial strain S. meliloti ARh29 had a positive effect on plant growth indices under salinity stress. In addition, the single inoculation of non-rhizobial strains without rhizobial strain resulted in an increase in alfalfa growth indices compared to the plants non-inoculated and the ones inoculated with S. meliloti ARh29 alone under salinity stress, indicating that nodule non-rhizobial strains have PGP potentials and may be a promising way for improving effectiveness of Rhizobium bio-fertilizers in salt-affected soils.},
}
@article {pmid29990337,
year = {2018},
author = {Ashworth, AJ and Toler, HD and Allen, FL and Augé, RM},
title = {Global meta-analysis reveals agro-grassland productivity varies based on species diversity over time.},
journal = {PloS one},
volume = {13},
number = {7},
pages = {e0200274},
doi = {10.1371/journal.pone.0200274},
pmid = {29990337},
issn = {1932-6203},
abstract = {Ecological research suggests increased diversity may improve ecosystem services, as well as yield stability; however, such theories are sometimes disproven by agronomic research, particularly at higher diversity levels. We conducted a meta-analysis on 2,753 studies in 48 articles published over the last 53 years to test: if biological N2 fixation (BNF) supplies adequate nitrogen (N) for plant growth relative to synthetic fertilizers; how crop physiological traits affect legume-grass symbiosis; and, how cultural practices affect BNF over a range of soils and climates overtime (in polycultures versus sole grasslands). Globally, net primary productivity (NPP; total aboveground production response of grass and legume in higher-diversity treatments) increased 44% via legume associations relative to sole grass controls (including both with and without N fertilizer). Several moderating variables affected NPP including: (i) plant photosynthetic pathway (mixtures of C3 grasses resulted in a 57% increase in NPP, whereas mixtures of C4 grasses resulted in a 31% increase; similarly cool-season legumes increased NPP 52% compared to a 27% increase for warm-season legumes relative to grasslands without diversity); (ii) legume life cycle [NPP response for perennial legume mixtures was 50% greater than sole grass controls, followed by a 28% increase for biennial, and a 0% increase for annual legumes)]; and, (iii) species richness (one leguminous species in a grassland agroecosystem resulted in 52% increase in NPP, whereas >2 legumes resulted in only 6% increases). Temporal and spatial effect sizes also influenced facilitation, considering facilitation was greatest (114% change) in Mediterranean climates followed by oceanic (84%), and tropical savanna (65%) environments; conversely, semiarid and subarctic systems had lowest Rhizobium-induced changes (5 and 0% change, respectively). Facilitation of grass production by legumes was also affected by soil texture. For example, a 122% NPP increase was observed in silt clay soils compared to 14% for silt loam soils. Niche complementarity effects were greatest prior to 1971 (61% change), compared to recent studies (2011-2016; -7% change), likely owing to reduced global sulfur deposition and increased ambient temperatures overtime. These historical trends suggest potential for legume intercrops to displace inorganic-N fertilizer and sustainably intensify global NPP. Results herein provide a framework for ecologists and agronomists to improve crop diversification systems, refine research goals, and heighten BNF capacities in agro-grasslands.},
}
@article {pmid29988452,
year = {2018},
author = {Li, H and Chen, M and Duan, L and Zhang, T and Cao, Y and Zhang, Z},
title = {Domain Swap Approach Reveals the Critical Roles of Different Domains of SYMRK in Root Nodule Symbiosis in Lotus japonicus.},
journal = {Frontiers in plant science},
volume = {9},
number = {},
pages = {697},
doi = {10.3389/fpls.2018.00697},
pmid = {29988452},
issn = {1664-462X},
abstract = {Symbiosis receptor kinase (SYMRK) is a cell membrane-localized protein kinase containing extracellular malectin-like domain (MLD) and leucine-rich repeat (LRR) domains, which is critically required for both root nodule symbiosis (RNS) and arbuscular mycorrhizal symbiosis (AMS). SYMRK is widely distributed in the genomes of different plant species; however, the contribution of different domains of SYMRK and its homologs from other plant species to RNS is largely unclear. In this study, SYMRK and its homologs from three typical plant species including Medicago truncatula (for both RNS and AMS), Oryza sativa (for AMS but not RNS), and Arabidopsis thaliana (for neither RNS or AMS) were investigated using domain swap approach in response to rhizobia in Lotus japonicus. Full-length SYMRK from rice and Medicago but not from Arabidopsis could complement Lotus symrk-409 mutant plants to contribute RNS. The chimeric protein with the extracellular domain (ED) of LjSYMRK and cytoplasmic domains (CD) of SYMRK from both Medicago and rice but not Arabidopsis could contribute to RNS in Lotus, suggesting that the CD of SYMRK is required for symbiotic signaling. The chimeric receptors containing the CD of LjSYMRK (SYMRKCD) and the EDs of MtDMI2 (MtDMI2ED), OsSYMRK (OsSYMRKED), AtSYMRK (AtSYMRKED), NFR1 (NFR1ED), and NFR5 (NFR5ED) could complement Lotus symrk-409 mutant plants to develop nodules. However, MtDMI2 could partially complement Lotus symrk-409 mutants to form both effective nodules and ineffective bumps, which is similar to the complementation results from MtDMI2ED-LjSYMRKCD and LjSYMRKGDLC in Lotus symrk-409 mutants, suggesting that ED of SYMRK has a very fine-tune regulation for RNS in Lotus. The deletion of either MLD or LRR on SYMRKGDLC (a mutant version of SYMRK with GDPC motif replaced by GDLC) could contribute to RNS when overexpressed in Lotus symrk-409 mutants, suggesting that MLD and LRR domains might work together to be involved in symbiotic signaling and the LRR domain might play a negative role in LjSYMRKGDLC-mediated RNS. By mutagenizing the conserved amino acids on LRR domain, five serine residues were found to be required for the function of LjSYMRKGDLC in RNS. These finding precisely refine the molecular mechanisms of SYMRK function in symbiotic signaling in L. japonicus.},
}
@article {pmid29986646,
year = {2018},
author = {Minter, EJA and Lowe, CD and Sørensen, MES and Wood, AJ and Cameron, DD and Brockhurst, MA},
title = {Variation and asymmetry in host-symbiont dependence in a microbial symbiosis.},
journal = {BMC evolutionary biology},
volume = {18},
number = {1},
pages = {108},
doi = {10.1186/s12862-018-1227-9},
pmid = {29986646},
issn = {1471-2148},
support = {NE/K011774/2//Natural Environment Research Council/International ; BB/M011151/1//Biotechnology and Biological Sciences Research Council/United Kingdom ; PLP-2014-242//Leverhulme Trust/International ; UF090328//The Royal Society/International ; },
mesh = {Animals ; Chlorella/*physiology ; Chlorophyll/metabolism ; Fluorescence ; Paramecium/growth &amp; development/*microbiology ; Symbiosis/*physiology ; },
abstract = {BACKGROUND: Symbiosis is a major source of evolutionary innovation and, by allowing species to exploit new ecological niches, underpins the functioning of ecosystems. The transition from free-living to obligate symbiosis requires the alignment of the partners' fitness interests and the evolution of mutual dependence. While symbiotic taxa are known to vary widely in the extent of host-symbiont dependence, rather less is known about variation within symbiotic associations.<br><br>RESULTS: Using experiments with the microbial symbiosis between the protist Paramecium bursaria and the alga Chlorella, we show variation between pairings in host-symbiont dependence, encompassing facultative associations, mutual dependence and host dependence upon the symbiont. Facultative associations, that is where both the host and the symbiont were capable of free-living growth, displayed higher symbiotic growth rates and higher per host symbiont loads than those with greater degrees of dependence.<br><br>CONCLUSIONS: These data show that the Paramecium-Chlorella interaction exists at the boundary between facultative and obligate symbiosis, and further suggest that the host is more likely to evolve dependence than the algal symbiont.},
}
@article {pmid29984706,
year = {2018},
author = {Wildgaard, L and Vendt, J and Wildgaard, K},
title = {[Information specialists improve the quality of systematic reviews].},
journal = {Ugeskrift for laeger},
volume = {180},
number = {28},
pages = {},
pmid = {29984706},
issn = {1603-6824},
abstract = {Systematic reviews (SR) are a recognised standard for synthesising clinical data in order to support evidence-based clinical decisions. A robust search strategy is the core of an SR, requiring theoretical and methodological considerations in the pre-, intra- and post-search stage. This review discusses the competencies necessary to design a search including the necessary symbiosis between medical knowledge and detailed knowledge of database architecture and corresponding semantics. Information specialists play an important role in high-quality SR.},
}
@article {pmid29982997,
year = {2018},
author = {Rivero, J and Álvarez, D and Flors, V and Azcón-Aguilar, C and Pozo, MJ},
title = {Root metabolic plasticity underlies functional diversity in mycorrhiza-enhanced stress tolerance in tomato.},
journal = {The New phytologist},
volume = {220},
number = {4},
pages = {1322-1336},
doi = {10.1111/nph.15295},
pmid = {29982997},
issn = {1469-8137},
support = {201440E046//CSIC/ ; 201440E099//CSIC/ ; AGL2015-64990-C2-1-R//MINECO/ ; CGL2015-69118-C2-2-P//MINECO/ ; FA1405//European Cooperation in Science and Technology/ ; },
abstract = {Arbuscular mycorrhizal (AM) symbioses can improve plant tolerance to multiple stresses. We compared three AM fungi (AMF) from different genera, one of them isolated from a dry and saline environment, in terms of their ability to increase tomato tolerance to moderate or severe drought or salt stress. Plant physiological parameters and metabolic profiles were compared in order to find the molecular mechanisms underlying plant protection against stress. Mycorrhizal growth response was determined, and ultrahigh-performance LC-MS was used to compare the metabolic profile of plants under the different treatments. All AMF increased plant tolerance to stress, and the positive effects of the symbiosis were correlated with the severity of the stress. The AMF isolated from the stressful environment was the most effective in improving plant tolerance to salt stress. Differentially accumulated compounds were identified and the antistress properties of some of them were confirmed. We demonstrate that AM symbioses increase plant metabolic plasticity to cope with stress. Some responses were common to all AMF tested, while others were specifically related to particular isolates. Important metabolism reprograming was evidenced upon salt stress, and we identified metabolic pathways and compounds differentially accumulated in mycorrhizas that may underlie their enhanced tolerance to stress.},
}
@article {pmid29982978,
year = {2018},
author = {Rocha, MLC and Cristaldo, PF and Cruz, JS and Sacramento, JJM and Ferreira, DV and Araújo, APA},
title = {Ants Associated with Turnera subulata (Turneraceae): Elaiosome Attraction, Seed Dispersion and Germination.},
journal = {Neotropical entomology},
volume = {47},
number = {6},
pages = {750-756},
doi = {10.1007/s13744-018-0616-5},
pmid = {29982978},
issn = {1678-8052},
abstract = {Symbiosis between plants and ants include examples in which the plant provides shelter and/or food for ants that, in turn, act in the defense or in the dispersion of seeds from the host plant. Although traditionally referred as mutualistic, the results of these interactions may vary with the ecological context in which patterns are involved. A range of species have facultative association with Turnera subulata (Turneraceae). Here, using behavioral bioassays, we investigated the effects of the most frequent ant species associated with T. subulata (Brachymyrmex sp.1, Camponotus blandus (Smith), Dorymyrmex sp.1, Crematogaster obscurata Emery, and Solenopsis invicta Buren) in the dispersion of plant host seeds and in the number of seedlings around the associated ant nests. We also evaluated the effects of these ant species in the germination of T. subulata seeds, in the consumption of elaiosome, and in the attractiveness to elaiosome odor. Our results showed that the ant species associated with T. subulata presented variation in the attraction by the odor and in the rate of consumption of the elaiosomes. However, none of the ant species studied contributed significantly to the increase of seed germination and seedling growth. Our results suggest that the consumption of the elaiosome by ant species is not a determinant factor to the success of germination of T. subulata. However, such species could contribute indirectly to seed germination by carrying seeds to sites more fertile to germination. In general, our results help to elucidate the results of ecological interactions involving ants and plants.},
}
@article {pmid29982531,
year = {2018},
author = {Bisch, G and Neuvonen, MM and Pierce, NE and Russell, JA and Koga, R and Sanders, JG and Lukasik, P and Andersson, SGE},
title = {Genome Evolution of Bartonellaceae Symbionts of Ants at the Opposite Ends of the Trophic Scale.},
journal = {Genome biology and evolution},
volume = {10},
number = {7},
pages = {1687-1704},
doi = {10.1093/gbe/evy126},
pmid = {29982531},
issn = {1759-6653},
mesh = {Animal Nutritional Physiological Phenomena ; Animals ; Ants/anatomy &amp; histology/*microbiology/physiology/ultrastructure ; Bartonellaceae/*genetics/physiology ; *Evolution, Molecular ; Gastrointestinal Microbiome ; Genome Size ; *Genome, Bacterial ; Phylogeny ; Symbiosis ; },
abstract = {Many insects rely on bacterial symbionts to supply essential amino acids and vitamins that are deficient in their diets, but metabolic comparisons of closely related gut bacteria in insects with different dietary preferences have not been performed. Here, we demonstrate that herbivorous ants of the genus Dolichoderus from the Peruvian Amazon host bacteria of the family Bartonellaceae, known for establishing chronic or pathogenic infections in mammals. We detected these bacteria in all studied Dolichoderus species, and found that they reside in the midgut wall, that is, the same location as many previously described nutritional endosymbionts of insects. The genomic analysis of four divergent strains infecting different Dolichoderus species revealed genes encoding pathways for nitrogen recycling and biosynthesis of several vitamins and all essential amino acids. In contrast, several biosynthetic pathways have been lost, whereas genes for the import and conversion of histidine and arginine to glutamine have been retained in the genome of a closely related gut bacterium of the carnivorous ant Harpegnathos saltator. The broad biosynthetic repertoire in Bartonellaceae of herbivorous ants resembled that of gut bacteria of honeybees that likewise feed on carbohydrate-rich diets. Taken together, the broad distribution of Bartonellaceae across Dolichoderus ants, their small genome sizes, the specific location within hosts, and the broad biosynthetic capability suggest that these bacteria are nutritional symbionts in herbivorous ants. The results highlight the important role of the host nutritional biology for the genomic evolution of the gut microbiota-and conversely, the importance of the microbiota for the nutrition of hosts.},
}
@article {pmid29981276,
year = {2018},
author = {Hume, BCC and D'Angelo, C and Smith, EG and Stevens, JR and Burt, JA and Wiedenmann, J},
title = {Validation of the binary designation Symbiodinium thermophilum (Dinophyceae).},
journal = {Journal of phycology},
volume = {54},
number = {5},
pages = {762-764},
doi = {10.1111/jpy.12764},
pmid = {29981276},
issn = {1529-8817},
support = {NE/K00641X/1//Natural Environment Research Council/ ; FP7/2007-2013/ERC//European Research Council under the European Union's Seventh Framework Programme/ ; 311179//European Research Council under the European Union's Seventh Framework Programme/ ; },
abstract = {The binary designation Symbiodinium thermophilum was invalid due to the absence of an illustration as required by Article 44.2 of the ICN. Herein, it is validated. This species is the most common symbiont in reef corals in the southern Persian/Arabian Gulf, the world's hottest body of water sustaining reef coral growth.},
}
@article {pmid29978521,
year = {2018},
author = {Merilaita, S and Kelley, JL},
title = {Scary clowns: adaptive function of anemonefish coloration.},
journal = {Journal of evolutionary biology},
volume = {31},
number = {10},
pages = {1558-1571},
doi = {10.1111/jeb.13350},
pmid = {29978521},
issn = {1420-9101},
support = {//Ella and Georg Ehrnrooth Foundation/ ; //School of Biological Sciences at The University of Western Australia/ ; },
abstract = {Clownfishes, with their showy coloration, are well known for their symbiosis with sea anemones and for their hierarchical reproductive system, but the function of their coloration is unclear. We used a phylogeny of 27 clownfish species to test whether fish coloration (i) serves a protective function that involves their anemone hosts, or (ii) signals species identity in species with overlapping host ranges that can potentially share the same host. We tested for an association between fish colour pattern traits, host morphology and host toxicity and examined coloration in relation to host sharing and geographic proximity. Fish with fewer stripes occupied fewer anemone species, and hosts with shorter tentacles, than fish with multiple stripes. There was a negative relationship between anemone toxicity and tentacle length and these protective traits together were correlated with the evolution of stripes. Host sharing or range overlap was not associated with coloration divergence. We propose that ancestral anemonefishes had multiple stripes that served for hiding/camouflage among the hosts' long tentacles, whereas increased specialization towards fewer and more toxic hosts (with shorter tentacles) led to the use of coloration as an aposematic signal. The intriguing notion that an aposematic signal could advertise the defence of another species may reflect the unique symbiotic relationship between anemonefishes and their hosts.},
}
@article {pmid29976607,
year = {2018},
author = {Andryuschenko, SV and Zdvizhkova, IA and Perunova, NB and Bukharin, OV},
title = {Draft Genome Sequence of Klebsiella pneumoniae Strain ICIS-278_PBV, Isolated from the Feces of a Healthy 59-Year-Old Man from Orenburg, Russia.},
journal = {Genome announcements},
volume = {6},
number = {27},
pages = {},
doi = {10.1128/genomeA.00576-18},
pmid = {29976607},
issn = {2169-8287},
abstract = {This report describes the draft genome sequence of Klebsiella pneumoniae strain ICIS-278_PBV, isolated from the feces of a healthy 59-year-old man from Orenburg, Russia. The size of the genome was 5,584,615 bp (57.2% G+C content). Annotation revealed 5,302 coding sequences, including 5,254 proteins, 23 rRNA genes, and 81 tRNA genes.},
}
@article {pmid29974222,
year = {2018},
author = {Dash, SK and Stezin, A and Takalkar, T and George, L and Kamble, NL and Netravathi, M and Yadav, R and Kumar, KJ and Ingalhalikar, M and Saini, J and Pal, PK},
title = {Abnormalities of white and grey matter in early multiple system atrophy: comparison of parkinsonian and cerebellar variants.},
journal = {European radiology},
volume = {},
number = {},
pages = {},
doi = {10.1007/s00330-018-5594-9},
pmid = {29974222},
issn = {1432-1084},
abstract = {OBJECTIVE: Multiple system atrophy (MSA) is a neurodegenerative disorder with progressive motor and autonomic dysfunction. There is a paucity of information on the early neurostructural changes in MSA, especially its subtypes, MSA-P (patients with predominant parkinsonism) and MSA-C (patients with predominant cerebellar signs). This study investigates the abnormalities of grey matter (GM) and white matter (WM) in early MSA and its subtypes using multi-modal voxel-based analysis.<br><br>MATERIALS AND METHODS: Twenty-six patients with MSA with duration of symptoms ≤ 2.5 years (mean duration: 1.6 ±0.9 years) were assessed clinically and with 3T MRI. Voxel-based morphometry (VBM) and diffusion tensor imaging (DTI) were performed to identify the structural changes in MSA and its subtypes. The GM changes and diffusion parameters of WM tracts were correlated with the clinical scores. The results were compared with MRI of 25 age- and gender-matched healthy controls.<br><br>RESULTS: The early structural changes in MSA included GM loss of the cerebellum and subcallosal gyrus with widespread involvement of supratentorial and infratentorial WM fibres. In MSA-C, GM loss was limited to the cerebellum with WM changes predominantly affecting the infratentorial WM and association tracts. In contrast, MSA-P did not demonstrate any GM loss and the WM involvement was mainly supratentorial. There was no significant correlation between structural changes and clinical severity score.<br><br>CONCLUSION: In early MSA, WM microstructure was more affected than GM. These changes were greater in MSA-C than in MSA-P, suggesting variable deterioration in the subtypes of MSA.<br><br>KEY POINTS: • Structural changes in early multiple system atrophy were evaluated using multi-modal neuroimaging. • White matter was more affected than grey matter in early MSA. • Clinical variables did not correlate with early structural changes.},
}
@article {pmid29974051,
year = {2018},
author = {Fankhauser, M and Moser, C and Nyfeler, T},
title = {Patents as Early Indicators of Technology and Investment Trends: Analyzing the Microbiome Space as a Case Study.},
journal = {Frontiers in bioengineering and biotechnology},
volume = {6},
number = {},
pages = {84},
doi = {10.3389/fbioe.2018.00084},
pmid = {29974051},
issn = {2296-4185},
abstract = {The human microbiome is the collective of microbes living in symbiosis on and within humans. Modulating its composition and function has become an attractive means for the prevention and treatment of a variety of diseases including cancer. Since the initiation of the human microbiome project in 2007, the number of academic publications and active patent families around the microbiome has grown exponentially. Screening patent databases can be useful for the early detection and the tracking of new technology trends. However, it is not sufficient to assess portfolio sizes because emerging players with small but high-quality patent portfolios will be missed within the noise of large but low-quality portfolio owners. Here we used the consolidated database and software tool PatentSight to benchmark patent portfolios, and to analyze key patent owners and innovators in the microbiome space. Our study shows how in-depth patent analyses combining qualitative and quantitative parameters can identify actionable early indicators of technology and investment trends from large patent datasets.},
}
@article {pmid29973926,
year = {2018},
author = {Chen, YX and Zou, L and Penttinen, P and Chen, Q and Li, QQ and Wang, CQ and Xu, KW},
title = {Faba Bean (Vicia faba L.) Nodulating Rhizobia in Panxi, China, Are Diverse at Species, Plant Growth Promoting Ability, and Symbiosis Related Gene Levels.},
journal = {Frontiers in microbiology},
volume = {9},
number = {},
pages = {1338},
doi = {10.3389/fmicb.2018.01338},
pmid = {29973926},
issn = {1664-302X},
abstract = {We isolated 65 rhizobial strains from faba bean (Vicia faba L.) from Panxi, China, studied their plant growth promoting ability with nitrogen free hydroponics, genetic diversity with clustered analysis of combined ARDRA and IGS-RFLP, and phylogeny by sequence analyses of 16S rRNA gene, three housekeeping genes and symbiosis related genes. Eleven strains improved the plant shoot dry mass significantly comparing to that of not inoculated plants. According to the clustered analysis of combined ARDRA and IGS-RFLP the isolates were genetically diverse. Forty-one of 65 isolates represented Rhizobium anhuiense, and the others belonged to R. fabae, Rhizobium vallis, Rhizobium sophorae, Agrobacterium radiobacter, and four species related to Rhizobium and Agrobacterium. The isolates carried four and five genotypes of nifH and nodC, respectively, in six different nifH-nodC combinations. When looking at the species-nifH-nodC combinations it is noteworthy that all but two of the six R. anhuiense isolates were different. Our results suggested that faba bean rhizobia in Panxi are diverse at species, plant growth promoting ability and symbiosis related gene levels.},
}
@article {pmid29972876,
year = {2018},
author = {Onchuru, TO and Martinez, AJ and Kaltenpoth, M},
title = {The cotton stainer's gut microbiota suppresses infection of a cotransmitted trypanosomatid parasite.},
journal = {Molecular ecology},
volume = {},
number = {},
pages = {},
doi = {10.1111/mec.14788},
pmid = {29972876},
issn = {1365-294X},
abstract = {The evolutionary and ecological success of many insects is attributed to mutualistic partnerships with bacteria that confer hosts with novel traits including food digestion, nutrient supplementation, detoxification of harmful compounds and defence against natural enemies. Dysdercus fasciatus firebugs (Hemiptera: Pyrrhocoridae), commonly known as cotton stainers, possess a simple but distinctive gut bacterial community including B vitamin-supplementing Coriobacteriaceae symbionts. In addition, their guts are often infested with the intestinal trypanosomatid parasite Leptomonas pyrrhocoris (Kinetoplastida: Trypanosomatidae). In this study, using experimental bioassays and fluorescence in situ hybridization (FISH), we report on the protective role of the D. fasciatus gut bacteria against L. pyrrhocoris. We artificially infected 2nd instars of dysbiotic and symbiotic insects with a parasite culture and measured parasite titres, developmental time and survival rates. Our results show that L. pyrrhocoris infection increases developmental time and slightly modifies the quantitative composition of the gut microbiota. More importantly, we found significantly higher parasite titres and a tendency towards lower survival rates in parasite-infected dysbiotic insects compared to symbiotic controls, indicating that the gut bacteria successfully interfere with the establishment or proliferation of L. pyrrhocoris. The colonization of symbiotic bacteria on the peritrophic matrix along the gut wall, as revealed by FISH, likely acts as a barrier blocking parasite attachment or entry into the hemolymph. Our findings show that in addition to being nutritionally important, D. fasciatus' gut bacteria complement the host's immune system in preventing parasite invasions and that a stable gut microbial community is integral for the host's health.},
}
@article {pmid29970951,
year = {2018},
author = {Chibeba, AM and Kyei-Boahen, S and Guimarães, MF and Nogueira, MA and Hungria, M},
title = {Feasibility of transference of inoculation-related technologies: A case study of evaluation of soybean rhizobial strains under the agro-climatic conditions of Brazil and Mozambique.},
journal = {Agriculture, ecosystems &amp; environment},
volume = {261},
number = {},
pages = {230-240},
doi = {10.1016/j.agee.2017.06.037},
pmid = {29970951},
issn = {0167-8809},
abstract = {The soybean-Bradyrhizobium symbiosis can be very effective in fixing nitrogen and supply nearly all plant's demand on this nutrient, obviating the need for N-fertilizers. Brazil has been investing in research and use of inoculants for soybean for decades and with the expansion of the crop in African countries, the feasibility of transference of biological nitrogen fixation (BNF) technologies between the continents should be investigated. We evaluated the performance of five strains (four Brazilian and one North American) in the 2013/2014 and 2014/2015 crop seasons in Brazil (four sites) and Mozambique (five sites). The experimental areas were located in relatively similar agro-climatic regions and had soybean nodulating rhizobial population ranging from ≪ 10 to 2 × 105 cells g-1 soil. The treatments were: (1) NI, non-inoculated control with no N-fertilizer; (2) NI + N, non-inoculated control with 200 kg of N ha-1; and inoculated with (3) Bradyrhizobium japonicum SEMIA 5079; (4) B. diazoefficiens SEMIA 5080; (5) B. elkanii SEMIA 587; (6) B. elkanii SEMIA 5019; (7) B. diazoefficiens USDA 110; (8) SEMIA 5079 + 5080 (only tested in Brazil). The best inoculation treatments across locations and crop seasons in Brazil were SEMIA 5079 + 5080, SEMIA 5079 and USDA 110, with average grain yield gains of 4-5% in relation to the non-inoculated treatment. SEMIA 5079, SEMIA 5080, SEMIA 5019 and USDA 110 were the best strains in Mozambique, with average 20-29% grain yield gains over the non-inoculated treatment. Moreover, the four best performing strains in Mozambique resulted in similar or better yields than the non-inoculated + N treatment, confirming the BNF as an alternative to N-fertilizers. The results also confirm the feasibility to transfer soybean inoculation technologies between countries, speeding up the establishment of sustainable cropping systems.},
}
@article {pmid29970949,
year = {2018},
author = {van Heerwaarden, J and Baijukya, F and Kyei-Boahen, S and Adjei-Nsiah, S and Ebanyat, P and Kamai, N and Wolde-Meskel, E and Kanampiu, F and Vanlauwe, B and Giller, K},
title = {Soyabean response to rhizobium inoculation across sub-Saharan Africa: Patterns of variation and the role of promiscuity.},
journal = {Agriculture, ecosystems &amp; environment},
volume = {261},
number = {},
pages = {211-218},
doi = {10.1016/j.agee.2017.08.016},
pmid = {29970949},
issn = {0167-8809},
abstract = {Improving bacterial nitrogen fixation in grain legumes is central to sustainable intensification of agriculture in sub-Saharan Africa. In the case of soyabean, two main approaches have been pursued: first, promiscuous varieties were developed to form effective symbiosis with locally abundant nitrogen fixing bacteria. Second, inoculation with elite bacterial strains is being promoted. Analyses of the success of these approaches in tropical smallholder systems are scarce. It is unclear how current promiscuous and non-promiscuous soyabean varieties perform in inoculated and uninoculated fields, and the extent of variation in inoculation response across regions and environmental conditions remains to be determined. We present an analysis of on-farm yields and inoculation responses across ten countries in Sub Saharan Africa, including both promiscuous and non-promiscuous varieties. By combining data from a core set of replicated on-farm trials with that from a large number of farmer-managed try-outs, we study the potential for inoculation to increase yields in both variety types and evaluate the magnitude and variability of response. Average yields were estimated to be 1343 and 1227 kg/ha with and without inoculation respectively. Inoculation response varied widely between trials and locations, with no clear spatial patterns at larger scales and without evidence that this variation could be explained by yield constraints or environmental conditions. On average, specific varieties had similar uninoculated yields, while responding more strongly to inoculation. Side-by side comparisons revealed that stronger responses were observed at sites where promiscuous varieties had superior uninoculated yields, suggesting the availability of compatible, effective bacteria as a yield limiting factor and as a determinant of the magnitude of inoculation response.},
}
@article {pmid29967517,
year = {2018},
author = {Li, FW and Brouwer, P and Carretero-Paulet, L and Cheng, S and de Vries, J and Delaux, PM and Eily, A and Koppers, N and Kuo, LY and Li, Z and Simenc, M and Small, I and Wafula, E and Angarita, S and Barker, MS and Bräutigam, A and dePamphilis, C and Gould, S and Hosmani, PS and Huang, YM and Huettel, B and Kato, Y and Liu, X and Maere, S and McDowell, R and Mueller, LA and Nierop, KGJ and Rensing, SA and Robison, T and Rothfels, CJ and Sigel, EM and Song, Y and Timilsena, PR and Van de Peer, Y and Wang, H and Wilhelmsson, PKI and Wolf, PG and Xu, X and Der, JP and Schluepmann, H and Wong, GK and Pryer, KM},
title = {Fern genomes elucidate land plant evolution and cyanobacterial symbioses.},
journal = {Nature plants},
volume = {4},
number = {7},
pages = {460-472},
doi = {10.1038/s41477-018-0188-8},
pmid = {29967517},
issn = {2055-0278},
abstract = {Ferns are the closest sister group to all seed plants, yet little is known about their genomes other than that they are generally colossal. Here, we report on the genomes of Azolla filiculoides and Salvinia cucullata (Salviniales) and present evidence for episodic whole-genome duplication in ferns-one at the base of 'core leptosporangiates' and one specific to Azolla. One fern-specific gene that we identified, recently shown to confer high insect resistance, seems to have been derived from bacteria through horizontal gene transfer. Azolla coexists in a unique symbiosis with N2-fixing cyanobacteria, and we demonstrate a clear pattern of cospeciation between the two partners. Furthermore, the Azolla genome lacks genes that are common to arbuscular mycorrhizal and root nodule symbioses, and we identify several putative transporter genes specific to Azolla-cyanobacterial symbiosis. These genomic resources will help in exploring the biotechnological potential of Azolla and address fundamental questions in the evolution of plant life.},
}
@article {pmid29959893,
year = {2018},
author = {Liu, H and Sandal, N and Andersen, KR and James, EK and Stougaard, J and Kelly, S and Kawaharada, Y},
title = {A genetic screen for plant mutants with altered nodulation phenotypes in response to rhizobial glycan mutants.},
journal = {The New phytologist},
volume = {220},
number = {2},
pages = {526-538},
doi = {10.1111/nph.15293},
pmid = {29959893},
issn = {1469-8137},
support = {DNRF79//Danish National Research Foundation/ ; 268523//ERC/ ; //Chinese Scholarship Council (CSC)/ ; },
abstract = {Nodule primordia induced by rhizobial glycan mutants often remain uninfected. To identify processes involved in infection and organogenesis we used forward genetics to identify plant genes involved in perception and responses to bacterial glycans. To dissect the mechanisms underlying the negative plant responses to the Mesorhizobium loti R7AexoU and ML001cep mutants, a screen for genetic suppressors of the nodulation phenotypes was performed on a chemically mutagenized Lotus population. Two mutant lines formed infected nitrogen-fixing pink nodules, while five mutant lines developed uninfected large white nodules, presumably altered in processes controlling organogenesis. Genetic mapping identified a mutation in the cytokinin receptor Lhk1 resulting in an alanine to valine substitution adjacent to a coiled-coil motif in the juxta-membrane region of LHK1. This results in a spontaneous nodulation phenotype and increased ethylene production. The allele was renamed snf5, and segregation studies of snf5 together with complementation studies suggest that snf5 is a gain-of-function allele. This forward genetic approach to investigate the role of glycans in the pathway synchronizing infection and organogenesis shows that a combination of plant and bacterial genetics opens new possibilities to study glycan responses in plants as well as identification of mutant alleles affecting nodule organogenesis.},
}
@article {pmid29957177,
year = {2018},
author = {Murakami, E and Cheng, J and Gysel, K and Bozsoki, Z and Kawaharada, Y and Hjuler, CT and Sørensen, KK and Tao, K and Kelly, S and Venice, F and Genre, A and Thygesen, MB and Jong, N and Vinther, M and Jensen, DB and Jensen, KJ and Blaise, M and Madsen, LH and Andersen, KR and Stougaard, J and Radutoiu, S},
title = {Epidermal LysM receptor ensures robust symbiotic signalling in Lotus japonicus.},
journal = {eLife},
volume = {7},
number = {},
pages = {},
doi = {10.7554/eLife.33506},
pmid = {29957177},
issn = {2050-084X},
support = {DNRF 79//Danmarks Grundforskningsfond/ ; Engineering Nitrogen Symbiosis for Africa//Engineering Nitrogen Symbiosis for Africa/ ; },
abstract = {Recognition of Nod factors by LysM receptors is crucial for nitrogen-fixing symbiosis in most legumes. The large families of LysM receptors in legumes suggest concerted functions, yet only NFR1 and NFR5 and their closest homologs are known to be required. Here we show that an epidermal LysM receptor (NFRe), ensures robust signalling in L. japonicus. Mutants of Nfre react to Nod factors with increased calcium spiking interval, reduced transcriptional response and fewer nodules in the presence of rhizobia. NFRe has an active kinase capable of phosphorylating NFR5, which in turn, controls NFRe downstream signalling. Our findings provide evidence for a more complex Nod factor signalling mechanism than previously anticipated. The spatio-temporal interplay between Nfre and Nfr1, and their divergent signalling through distinct kinases suggests the presence of an NFRe-mediated idling state keeping the epidermal cells of the expanding root system attuned to rhizobia.},
}
@article {pmid29957169,
year = {2018},
author = {De Meyer, SE and Cnockaert, M and Moulin, L and Howieson, JG and Vandamme, P},
title = {Symbiotic and non-symbiotic Paraburkholderia isolated from South African Lebeckia ambigua root nodules and the description of Paraburkholderia fynbosensis sp. nov.},
journal = {International journal of systematic and evolutionary microbiology},
volume = {68},
number = {8},
pages = {2607-2614},
doi = {10.1099/ijsem.0.002884},
pmid = {29957169},
issn = {1466-5034},
mesh = {Bacterial Typing Techniques ; Base Composition ; Burkholderiaceae/*classification/isolation &amp; purification ; DNA, Bacterial/genetics ; Fabaceae/*microbiology ; Fatty Acids/chemistry ; Nucleic Acid Hybridization ; *Phylogeny ; Quinones/chemistry ; RNA, Ribosomal, 16S/genetics ; Root Nodules, Plant/*microbiology ; Sequence Analysis, DNA ; South Africa ; Symbiosis ; },
abstract = {Nine Gram-negative, rod-shaped bacteria were isolated from Lebeckia ambigua root nodules. All strains were able to nodulate and fix nitrogen with Lebeckia ambigua apart from WSM4178T, WSM4181 and WSM4182. Based on the 16S rRNA gene phylogeny, all strains were closely related to Paraburkholderia species (98.4-99.9 %), belonging to the Betaproteobacteria class and Burkholderiaceae family. According to 16S rRNA gene phylogeny the closest relative for WSM4174-WSM4177 and WSM4179-WSM4180 was Paraburkholderia tuberum(99.80-99.86 %), for WSM4178T was Paraburkholderia caledonica (98.42 %) and for WSM4181-WSM4182 was Paraburkholderia graminis (99.79 %). Analysis of the gyrB and recA housekeeping genes supported the assignment of WSM4181-WSM4182 to P. graminis and the other investigated strains could be assigned to the genus Paraburkholderia. The results of DNA-DNA hybridization, physiological and biochemical tests allowed genotypic and phenotypic differentiation of WSM4178T from the closest validly published Paraburkholderia species. However, WSM4174-WSM4177 and WSM4179-WSM4180 could not reliably be distinguished from its closest neighbour and therefore complete genome comparison was performed between WSM4176 and P. tuberum STM678T which gave ANI values of 96-97 %. Chemotaxonomic data, including fatty acid profiles and quinone data supported the assignment of the strains to the genus Paraburkholderia. On the basis of genotypic and phenotypic data one novel species, Paraburkholderiafynbosensis sp. nov. (WSM4178T=LMG 27177T=HAMBI 3356T), is proposed and the isolation of P. tuberum and P. graminis from root nodules of Lebeckia ambigua is reported.},
}
@article {pmid29954096,
year = {2018},
author = {Andrews, M and De Meyer, S and James, EK and Stępkowski, T and Hodge, S and Simon, MF and Young, JPW},
title = {Horizontal Transfer of Symbiosis Genes within and Between Rhizobial Genera: Occurrence and Importance.},
journal = {Genes},
volume = {9},
number = {7},
pages = {},
doi = {10.3390/genes9070321},
pmid = {29954096},
issn = {2073-4425},
abstract = {Rhizobial symbiosis genes are often carried on symbiotic islands or plasmids that can be transferred (horizontal transfer) between different bacterial species. Symbiosis genes involved in horizontal transfer have different phylogenies with respect to the core genome of their &amp;lsquo;host&amp;rsquo;. Here, the literature on legume⁻rhizobium symbioses in field soils was reviewed, and cases of phylogenetic incongruence between rhizobium core and symbiosis genes were collated. The occurrence and importance of horizontal transfer of rhizobial symbiosis genes within and between bacterial genera were assessed. Horizontal transfer of symbiosis genes between rhizobial strains is of common occurrence, is widespread geographically, is not restricted to specific rhizobial genera, and occurs within and between rhizobial genera. The transfer of symbiosis genes to bacteria adapted to local soil conditions can allow these bacteria to become rhizobial symbionts of previously incompatible legumes growing in these soils. This, in turn, will have consequences for the growth, life history, and biogeography of the legume species involved, which provides a critical ecological link connecting the horizontal transfer of symbiosis genes between rhizobial bacteria in the soil to the above-ground floral biodiversity and vegetation community structure.},
}
@article {pmid29951968,
year = {2018},
author = {Dejean, A and Azémar, F and Petitclerc, F and Delabie, JHC and Corbara, B and Leroy, C and Céréghino, R and Compin, A},
title = {Highly modular pattern in ant-plant interactions involving specialized and non-specialized myrmecophytes.},
journal = {Die Naturwissenschaften},
volume = {105},
number = {7-8},
pages = {43},
doi = {10.1007/s00114-018-1570-0},
pmid = {29951968},
issn = {1432-1904},
support = {CEBA, ref. ANR-10- LABX-25-01//Agence Nationale de la Recherche/ ; },
mesh = {Animals ; Ants/*physiology ; *Ecosystem ; Host Specificity ; *Plant Physiological Phenomena ; Symbiosis ; },
abstract = {Because Tachia guianensis (Gentianaceae) is a &quot;non-specialized myrmecophyte&quot; associated with 37 ant species, we aimed to determine if its presence alters the ant guild associated with sympatric &quot;specialized myrmecophytes&quot; (i.e., plants sheltering a few ant species in hollow structures). The study was conducted in a hilly zone of a neotropical rainforest where two specialized myrmecophytes grow at the bottom of the slopes, another at mid-slope, and a fourth on the hilltops. Tachia guianensis, which occurred everywhere, had its own guild of associated ant species. A network analysis showed that its connections with the four other myrmecophytes were rare and weak, the whole resulting in a highly modular pattern of interactions with one module (i.e., subnetwork) per myrmecophyte. Three ant species parasitized three out of the four specialized myrmecophytes (low nestedness noted), but were not or barely associated with T. guianensis that therefore did not influence the parasitism of specialized myrmecophytes.},
}
@article {pmid29951892,
year = {2018},
author = {Sharma, N and Baruah, MM},
title = {The microRNA signatures: aberrantly expressed miRNAs in prostate cancer.},
journal = {Clinical &amp; translational oncology : official publication of the Federation of Spanish Oncology Societies and of the National Cancer Institute of Mexico},
volume = {},
number = {},
pages = {},
doi = {10.1007/s12094-018-1910-8},
pmid = {29951892},
issn = {1699-3055},
abstract = {MicroRNAs (miRNAs) are short, non-coding, conserved, oligonucleotides that are regulatory in nature and are often dysregulated in many cancers including prostate cancer. Depending on the level of complementarity between the miRNA and mRNA target, they can either inhibit translation or degrade the target mRNA. MiRNAs expression is specific to the type of cancer, its stage and level of metastasis, making miRNAs potential stage-specific biomarkers of cancer. Recent research has shown that these miRNAs have the potential to be a diagnostic and prognostic non-invasive biomarker for various cancers including prostate cancer. Various miRNAs have been reported as novel biomarkers for prostate cancer therapy. However, there is inconsistency in the data reported and no overlapping expression pattern could be found. In this review, we have highlighted the most consistently reported dysregulated miRNAs in prostate cancer from the existing literature and discussed the currently available data on their role in regulating the hallmarks of prostate cancer. These four most consistently reported dysregulated miRNAs viz. miRNA-141, miRNA-375, miRNA-221 and miRNA-21 need to be further validated in terms of their regulatory potential in regulating various pathways important for prostate cancer management.},
}
@article {pmid29951862,
year = {2018},
author = {Qin, Y and Duan, G and Zhao, Z and Tian, H and Solaiman, ZM},
title = {18O-labeled phosphate applied to soil appears in the shoots of maize after uptake by roots but not after uptake by an arbuscular mycorrhizal fungus.},
journal = {Mycorrhiza},
volume = {28},
number = {8},
pages = {787-793},
doi = {10.1007/s00572-018-0849-5},
pmid = {29951862},
issn = {1432-1890},
abstract = {The application of 33P or 32P isotopes to directly trace phosphorus (P) uptake during arbuscular mycorrhizal (AM) symbiosis is limited by the radioactivity of the two P isotopes, especially under field conditions. A potential alternative method for tracing P uptake in plant-soil systems relies on the analysis of the stable oxygen (O) isotopes of ortho-phosphate (Pi); however, little is known about the fate of the P-O bond during Pi uptake in AM symbioses. This study investigated whether the abundance of 18O in Pi extracted from the shoots of maize increased after 18O-labeled Pi added to soil was taken up by either roots of maize or AM extraradical hyphae. A two-compartment culture system, consisting of a root and AM hyphal compartment (RHC, including both roots and AM hyphae) and an AM hyphal compartment (HC, including only hyphae) was designed, and the AM fungus Funneliformis mosseae was used to inoculate the roots of maize. Our results indicated that the abundance of 18O in Pi extracted from the maize shoots increased significantly 3 months after the addition of 18O-labeled Pi to the soil in the pots which only contained roots. The abundance of 18O was much lower than expected, however, which suggests a great majority of 18O in labeled Pi was lost in the soil or during Pi metabolism in the shoots of maize. The abundance of 18O in Pi extracted from the maize shoots did not increase 3 months after 18O-labeled Pi was added to the HC, and therefore, loss of 18O in labeled Pi may also occur during Pi metabolism in AM hyphae. Use of 18O-labeled Pi as a qualitative tracer of P uptake during AM symbiosis appears unfeasible for such a long-term (3 months) experiment, although it should be investigated in a short-term labeling experiment.},
}
@article {pmid29951740,
year = {2019},
author = {Kulkarni, RS and Bajaj, MS and Kale, VP},
title = {Induction and Detection of Autophagy in Aged Hematopoietic Stem Cells by Exposing Them to Microvesicles Secreted by HSC-Supportive Mesenchymal Stromal Cells.},
journal = {Methods in molecular biology (Clifton, N.J.)},
volume = {1854},
number = {},
pages = {21-34},
doi = {10.1007/7651_2018_166},
pmid = {29951740},
issn = {1940-6029},
abstract = {Autophagy is an important cellular process for maintenance of quality and functionality of cells. This happens through repair and renewal of cellular components like proteins and mitochondria. Reduction in autophagy process in aged hematopoietic stem cells (HSCs) leads to their compromised stemness and self-renewal capacity, and consequently, their applicability in various regenerative therapies also reduces. HSC functions are regulated by their microenvironment, known as &quot;HSC niche,&quot; which comprises of mesenchymal stromal cells (MSCs), osteoblasts, endothelial cells, etc. In this niche, the MSCs are known to closely interact with the HSCs, and therefore, they can directly influence the stem cell fate. In our earlier studies, we have demonstrated that young MSCs or aged MSCs rejuvenated by treating them with LY294002, a PI3K inhibitor (rescued aged MSCs), rejuvenate aged HSCs via intercellular transfer of microvesicles (MVs) harboring autophagy-inducing mRNAs.Here, we describe the protocol for induction of autophagy in aged HSCs by incubating them with microvesicles (MVs) collected from young MSCs or rescued aged MSCs. We also describe the protocols for determination of autophagy levels in these HSCs.},
}
@article {pmid29949657,
year = {2018},
author = {Mathieu, S and Cusant, L and Roux, C and Corradi, N},
title = {Arbuscular mycorrhizal fungi: intraspecific diversity and pangenomes.},
journal = {The New phytologist},
volume = {220},
number = {4},
pages = {1129-1134},
doi = {10.1111/nph.15275},
pmid = {29949657},
issn = {1469-8137},
support = {//Natural Sciences and Engineering Research Council of Canada/ ; ER13-09-190//Ontario Ministry of Research and Innovation/ ; ANR-10-LABX-41//French Ministry of Higher Education, Research and Innovation (MESRI)/ ; },
abstract = {Contents Summary 1129 I. Introduction 1129 II. Intraspecific phenotypic variation and the plant host 1130 III. High inter-isolate genetic diversity in model AMF 1130 IV. Genome diversity within the model AM fungus Rhizophagus irregularis 1131 V. Pangenomes and the future of AMF ecological genomics 1131 Acknowledgements 1133 References 1133 SUMMARY: Arbuscular mycorrhizal fungi (AMF) are ubiquitous plant symbionts with an intriguing population biology. Conspecific AMF strains can vary substantially at the genetic and phenotypic levels, leading to direct and quantifiable variation in plant growth. Recent studies have shown that high intraspecific diversity is very common in AMF, and not only found in model species. Studies have also revealed how the phenotype of conspecific isolates varies depending on the plant host, highlighting the functional relevance of intraspecific phenotypic plasticity for the AMF ecology and mycorrhizal symbiosis. Recent work has also demonstrated that conspecific isolates of the model AMF Rhizophagus irregularis harbor large and highly variable pangenomes, highlighting the potential role of intraspecific genome diversity for the ecological adaptation of these symbionts.},
}
@article {pmid29948922,
year = {2018},
author = {Kutschera, U},
title = {Systems biology of eukaryotic superorganisms and the holobiont concept.},
journal = {Theory in biosciences = Theorie in den Biowissenschaften},
volume = {137},
number = {2},
pages = {117-131},
doi = {10.1007/s12064-018-0265-6},
pmid = {29948922},
issn = {1611-7530},
support = {Stanford U. Kut. 2013/14//Alexander von Humboldt-Stiftung/ ; },
abstract = {The founders of modern biology (Jean Lamarck, Charles Darwin, August Weismann etc.) were organismic life scientists who attempted to understand the morphology and evolution of living beings as a whole (i.e., the phenotype). However, with the emergence of the study of animal and plant physiology in the nineteenth century, this &quot;holistic view&quot; of the living world changed and was ultimately replaced by a reductionistic perspective. Here, I summarize the history of systems biology, i.e., the modern approach to understand living beings as integrative organisms, from genotype to phenotype. It is documented that the physiologists Claude Bernard and Julius Sachs, who studied humans and plants, respectively, were early pioneers of this discipline, which was formally founded 50 years ago. In 1968, two influential monographs, authored by Ludwig von Bertalanffy and Mihajlo D. Mesarović, were published, wherein a &quot;systems theory of biology&quot; was outlined. Definitions of systems biology are presented with reference to metabolic or cell signaling networks, analyzed via genomics, proteomics, and other methods, combined with computer simulations/mathematical modeling. Then, key insights of this discipline with respect to epiphytic microbes (Methylobacterium sp.) and simple bacteria (Mycoplasma sp.) are described. The principles of homeostasis, molecular systems energetics, gnotobiology, and holobionts (i.e., complexities of host-microbiota interactions) are outlined, and the significance of systems biology for evolutionary theories is addressed. Based on the microbe-Homo sapiens-symbiosis, it is concluded that human biology and health should be interpreted in light of a view of the biomedical sciences that is based on the holobiont concept.},
}
@article {pmid29948488,
year = {2018},
author = {Yoshida, Y},
title = {The cellular machineries responsible for the division of endosymbiotic organelles.},
journal = {Journal of plant research},
volume = {131},
number = {5},
pages = {727-734},
doi = {10.1007/s10265-018-1050-9},
pmid = {29948488},
issn = {1618-0860},
support = {Career Development Award/CDA00049/2018-C//Human Frontier Science Program/ ; KAKENHI/JP18K06325//Japan Society for the Promotion of Science/ ; },
mesh = {Cell Division ; Chloroplasts/physiology/ultrastructure ; Mitochondria/physiology/ultrastructure ; Organelles/physiology/*ultrastructure ; Plastids/physiology/ultrastructure ; Rhodophyta/physiology/*ultrastructure ; *Symbiosis ; },
abstract = {Chloroplasts (plastids) and mitochondria evolved from endosymbiotic bacteria. These organelles perform vital functions in photosynthetic eukaryotes, such as harvesting and converting energy for use in biological processes. Consistent with their evolutionary origins, plastids and mitochondria proliferate by the binary fission of pre-existing organelles. Here, I review the structures and functions of the supramolecular machineries driving plastid and mitochondrial division, which were discovered and first studied in the primitive red alga Cyanidioschyzon merolae. In the past decade, intact division machineries have been isolated from plastids and mitochondria and examined to investigate their underlying structure and molecular mechanisms. A series of studies has elucidated how these division machineries assemble and transform during the fission of these organelles, and which of the component proteins generate the motive force for their contraction. Plastid- and mitochondrial-division machineries have important similarities in their structures and mechanisms despite sharing no component proteins, implying that these division machineries evolved in parallel. The establishment of these division machineries might have enabled the host eukaryotic ancestor to permanently retain these endosymbiotic organelles by regulating their binary fission and the equal distribution of resources to daughter cells. These findings provide key insights into the establishment of endosymbiotic organelles and have opened new avenues of research into their evolution and mechanisms of proliferation.},
}
@article {pmid29948435,
year = {2018},
author = {Linnakoski, R and Kasanen, R and Lasarov, I and Marttinen, T and Oghenekaro, AO and Sun, H and Asiegbu, FO and Wingfield, MJ and Hantula, J and Heliövaara, K},
title = {Cadophora margaritata sp. nov. and other fungi associated with the longhorn beetles Anoplophora glabripennis and Saperda carcharias in Finland.},
journal = {Antonie van Leeuwenhoek},
volume = {111},
number = {11},
pages = {2195-2211},
doi = {10.1007/s10482-018-1112-y},
pmid = {29948435},
issn = {1572-9699},
support = {University of Helsinki Postdoc Pool//Helsingin Yliopisto/ ; },
abstract = {Symbiosis with microbes is crucial for survival and development of wood-inhabiting longhorn beetles (Coleoptera: Cerambycidae). Thus, knowledge of the endemic fungal associates of insects would facilitate risk assessment in cases where a new invasive pest occupies the same ecological niche. However, the diversity of fungi associated with insects remains poorly understood. The aim of this study was to investigate fungi associated with the native large poplar longhorn beetle (Saperda carcharias) and the recently introduced Asian longhorn beetle (Anoplophora glabripennis) infesting hardwood trees in Finland. We studied the cultivable fungal associates obtained from Populus tremula colonised by S. carcharias, and Betula pendula and Salix caprea infested by A. glabripennis, and compared these to the samples collected from intact wood material. This study detected a number of plant pathogenic and saprotrophic fungi, and species with known potential for enzymatic degradation of wood components. Phylogenetic analyses of the most commonly encountered fungi isolated from the longhorn beetles revealed an association with fungi residing in the Cadophora-Mollisia species complex. A commonly encountered fungus was Cadophora spadicis, a recently described fungus associated with wood-decay. In addition, a novel species of Cadophora, for which the name Cadophora margaritata sp. nov. is provided, was isolated from the colonised wood.},
}
@article {pmid29948410,
year = {2018},
author = {Prihatna, C and Larkan, NJ and Barbetti, MJ and Barker, SJ},
title = {Tomato CYCLOPS/IPD3 is required for mycorrhizal symbiosis but not tolerance to Fusarium wilt in mycorrhiza-deficient tomato mutant rmc.},
journal = {Mycorrhiza},
volume = {28},
number = {5-6},
pages = {495-507},
doi = {10.1007/s00572-018-0842-z},
pmid = {29948410},
issn = {1432-1890},
mesh = {Disease Resistance ; Fusarium/pathogenicity ; Gene Deletion ; Genetic Complementation Test ; Lycopersicon esculentum/*genetics/microbiology ; *Mutation ; Mycorrhizae ; Plant Diseases/*microbiology ; Plant Proteins/*genetics ; Plant Roots/genetics/microbiology ; Promoter Regions, Genetic ; Symbiosis ; },
abstract = {Mycorrhizal symbiosis requires several common symbiosis genes including CYCLOPS/IPD3. The reduced mycorrhizal colonisation (rmc) tomato mutant has a deletion of five genes including CYCLOPS/IPD3, and rmc is more susceptible to Fusarium wilt than its wild-type parental line. This study investigated the genetic defects leading to both fungal interaction phenotypes and whether these were separable. Complementation was performed in rmc to test the requirement for CYCLOPS/IPD3 in mycorrhiza formation and Fusarium wilt tolerance. Promoter analysis via GFP expression in roots was conducted to determine the role of native regulatory elements in the proper functioning of CYCLOPS/IPD3. CYCLOPS/IPD3 regulated by its native promoter, but not a 2×35S promoter, restores mycorrhizal association in rmc. GFP regulated by the 2×35S promoter is not expressed in epidermal cells of roots, indicating that expression of CYCLOPS/IPD3 in these cells is required for colonisation by the fungi utilised in this research. CYCLOPS/IPD3 did not restore Fusarium wilt tolerance, however, showing that the genetic requirements for mycorrhizal association and Fusarium wilt tolerance are different. Our results confirm the expected role of CYCLOPS/IPD3 in mycorrhizal symbiosis and suggest that Fusarium tolerance is conferred by one of the other four genes affected by the deletion.},
}
@article {pmid29948017,
year = {2018},
author = {Mason, CJ and Campbell, AM and Scully, ED and Hoover, K},
title = {Bacterial and Fungal Midgut Community Dynamics and Transfer Between Mother and Brood in the Asian Longhorned Beetle (Anoplophora glabripennis), an Invasive Xylophage.},
journal = {Microbial ecology},
volume = {},
number = {},
pages = {},
doi = {10.1007/s00248-018-1205-1},
pmid = {29948017},
issn = {1432-184X},
support = {2015-67013-23287//National Institute of Food and Agriculture/ ; },
abstract = {Microbial symbionts play pivotal roles in the ecology and physiology of insects feeding in woody plants. Both eukaryotic and bacterial members occur in these systems where they facilitate digestive and nutrient provisioning. The larval gut of the Asian longhorned beetle (Anoplophora glabripennis) is associated with a microbial consortium that fulfills these metabolic roles. While members of the community vary in presence and abundance among individuals from different hosts, A. glabripennis is consistently associated with a fungus in the Fusarium solani species complex (FSSC). We used amplicon sequencing, taxon-specific PCR, culturing, and imaging to determine how bacterial and fungal communities differ between life stages and possible modes of symbiont transfer. The bacterial and fungal communities of adult guts were more diverse than those from larvae and eggs. The communities of larvae and eggs were more similar to those from oviposition sites than from adult female guts. FSSC isolates were not detected in the reproductive tissues of adult females, but were consistently detected on egg surfaces after oviposition and in frass. These results demonstrate that frass can serve as a vehicle of transmission of a subset for the beetle gut microbiota. Vertically transmitted symbionts are often beneficial to their host, warranting subsequent functional studies.},
}
@article {pmid29947761,
year = {2018},
author = {Faria, VG and Martins, NE and Schlötterer, C and Sucena, É},
title = {Readapting to DCV Infection without Wolbachia: Frequency Changes of Drosophila Antiviral Alleles Can Replace Endosymbiont Protection.},
journal = {Genome biology and evolution},
volume = {10},
number = {7},
pages = {1783-1791},
doi = {10.1093/gbe/evy137},
pmid = {29947761},
issn = {1759-6653},
support = {P 27630//Austrian Science Fund FWF/Austria ; },
mesh = {Adaptation, Physiological ; Alleles ; Animals ; Drosophila melanogaster/genetics/*microbiology/physiology/*virology ; Genome, Insect ; Host-Pathogen Interactions ; Insect Viruses/*physiology ; Polymorphism, Genetic ; *Symbiosis ; Wolbachia/*physiology ; },
abstract = {There is now ample evidence that endosymbionts can contribute to host adaptation to environmental challenges. However, how endosymbiont presence affects the adaptive trajectory and outcome of the host is yet largely unexplored. In Drosophila, Wolbachia confers protection to RNA virus infection, an effect that differs between Wolbachia strains and can be targeted by selection. Adaptation to RNA virus infections is mediated by both Wolbachia and the host, raising the question of whether adaptive genetic changes in the host vary with the presence/absence of the endosymbiont. Here, we address this question using a polymorphic D. melanogaster population previously adapted to DCV infection for 35 generations in the presence of Wolbachia, from which we removed the endosymbiont and followed survival over the subsequent 20 generations of infection. After an initial severe drop, survival frequencies upon DCV selection increased significantly, as seen before in the presence of Wolbachia. Whole-genome sequencing, revealed that the major genes involved in the first selection experiment, pastrel and Ubc-E2H, continued to be selected in Wolbachia-free D. melanogaster, with the frequencies of protective alleles being closer to fixation in the absence of Wolbachia. Our results suggest that heterogeneity in Wolbachia infection status may be sufficient to maintain polymorphisms even in the absence of costs.},
}
@article {pmid29947506,
year = {2018},
author = {Misztal, PK and Lymperopoulou, DS and Adams, RI and Scott, RA and Lindow, SE and Bruns, T and Taylor, JW and Uehling, J and Bonito, G and Vilgalys, R and Goldstein, AH},
title = {Emission Factors of Microbial Volatile Organic Compounds from Environmental Bacteria and Fungi.},
journal = {Environmental science &amp; technology},
volume = {52},
number = {15},
pages = {8272-8282},
doi = {10.1021/acs.est.8b00806},
pmid = {29947506},
issn = {1520-5851},
abstract = {Knowledge of the factors controlling the diverse chemical emissions of common environmental bacteria and fungi is crucial because they are important signal molecules for these microbes that also could influence humans. We show here not only a high diversity of mVOCs but that their abundance can differ greatly in different environmental contexts. Microbial volatiles exhibit dynamic changes across microbial growth phases, resulting in variance of composition and emission rate of species-specific and generic mVOCs. In vitro experiments documented emissions of a wide range of mVOCs (>400 different chemicals) at high time resolution from diverse microbial species grown under different controlled conditions on nutrient media, or residential structural materials (N = 54, Ncontrol = 23). Emissions of mVOCs varied not only between microbial taxa at a given condition but also as a function of life stage and substrate type. We quantify emission factors for total and specific mVOCs normalized for respiration rates to account for the microbial activity during their stationary phase. Our VOC measurements of different microbial taxa indicate that a variety of factors beyond temperature and water activity, such as substrate type, microbial symbiosis, growth phase, and lifecycle affect the magnitude and composition of mVOC emission.},
}
@article {pmid29946965,
year = {2018},
author = {Sharma, M and Bennewitz, B and Klösgen, RB},
title = {Rather rule than exception? How to evaluate the relevance of dual protein targeting to mitochondria and chloroplasts.},
journal = {Photosynthesis research},
volume = {138},
number = {3},
pages = {335-343},
doi = {10.1007/s11120-018-0543-7},
pmid = {29946965},
issn = {1573-5079},
mesh = {Biological Assay ; Biological Evolution ; Chloroplasts/*metabolism ; Mitochondria/*metabolism ; Protein Transport ; Symbiosis ; },
abstract = {Dual targeting of a nuclearly encoded protein into two different cell organelles is an exceptional event in eukaryotic cells. Yet, the frequency of such dual targeting is remarkably high in case of mitochondria and chloroplasts, the two endosymbiotic organelles of plant cells. In most instances, it is mediated by &quot;ambiguous&quot; transit peptides, which recognize both organelles as the target. A number of different approaches including in silico, in organello as well as both transient and stable in vivo assays are established to determine the targeting specificity of such transit peptides. In this review, we will describe and compare these approaches and discuss the potential role of this unusual targeting process. Furthermore, we will present a hypothetical scenario how dual targeting might have arisen during evolution.},
}
@article {pmid29946739,
year = {2018},
author = {Sajnaga, E and Kazimierczak, W and Skowronek, M and Lis, M and Skrzypek, T and Waśko, A},
title = {Steinernema poinari (Nematoda: Steinernematidae): a new symbiotic host of entomopathogenic bacteria Xenorhabdus bovienii.},
journal = {Archives of microbiology},
volume = {200},
number = {9},
pages = {1307-1316},
doi = {10.1007/s00203-018-1544-9},
pmid = {29946739},
issn = {1432-072X},
abstract = {Three strains of symbiotic bacteria were isolated from an entomopathogenic nematode Steinernema poinari retrieved from soil in eastern Poland. Using 16S rDNA, recA, gltX, gyrB, and dnaN gene sequences for phylogenetic analysis, these strains were shown to belong to the species Xenorhabdus bovienii. The nucleotide identity between the studied S. poinari microsymbionts and other X. bovienii strains calculated for 16S rDNA and concatenated sequences of four protein-coding genes was 98.7-100% and 97.9-99.5%, respectively. The phenotypic properties of the isolates also supported their close phylogenetic relationship with X. bovienii. All three tested X. bovienii strains of different Steinernema clade origin supported the recovery of infective juveniles and subsequent development of the nematode population. However, the colonization degree of new infective juvenile generations was significantly affected by the bacterial host donor/recipient. The colonization degree of infective juveniles reared on bacterial symbionts deriving from a non-cognate clade of nematodes was extremely low, but proved the possible host-switching between non-related Steinernema species.},
}
@article {pmid29946103,
year = {2018},
author = {Flórez, LV and Scherlach, K and Miller, IJ and Rodrigues, A and Kwan, JC and Hertweck, C and Kaltenpoth, M},
title = {An antifungal polyketide associated with horizontally acquired genes supports symbiont-mediated defense in Lagria villosa beetles.},
journal = {Nature communications},
volume = {9},
number = {1},
pages = {2478},
doi = {10.1038/s41467-018-04955-6},
pmid = {29946103},
issn = {2041-1723},
abstract = {Microbial symbionts are often a source of chemical novelty and can contribute to host defense against antagonists. However, the ecological relevance of chemical mediators remains unclear for most systems. Lagria beetles live in symbiosis with multiple strains of Burkholderia bacteria that protect their offspring against pathogens. Here, we describe the antifungal polyketide lagriamide, and provide evidence supporting that it is produced by an uncultured symbiont, Burkholderia gladioli Lv-StB, which is dominant in field-collected Lagria villosa. Interestingly, lagriamide is structurally similar to bistramides, defensive compounds found in marine tunicates. We identify a gene cluster that is probably involved in lagriamide biosynthesis, provide evidence for horizontal acquisition of these genes, and show that the naturally occurring symbiont strains on the egg are protective in the soil environment. Our findings highlight the potential of microbial symbionts and horizontal gene transfer as influential sources of ecological innovation.},
}
@article {pmid29946051,
year = {2018},
author = {Hendry, TA and Freed, LL and Fader, D and Fenolio, D and Sutton, TT and Lopez, JV},
title = {Ongoing Transposon-Mediated Genome Reduction in the Luminous Bacterial Symbionts of Deep-Sea Ceratioid Anglerfishes.},
journal = {mBio},
volume = {9},
number = {3},
pages = {},
doi = {10.1128/mBio.01033-18},
pmid = {29946051},
issn = {2150-7511},
abstract = {Diverse marine fish and squid form symbiotic associations with extracellular bioluminescent bacteria. These symbionts are typically free-living bacteria with large genomes, but one known lineage of symbionts has undergone genomic reduction and evolution of host dependence. It is not known why distinct evolutionary trajectories have occurred among different luminous symbionts, and not all known lineages previously had genome sequences available. In order to better understand patterns of evolution across diverse bioluminescent symbionts, we de novo sequenced the genomes of bacteria from a poorly studied interaction, the extracellular symbionts from the &quot;lures&quot; of deep-sea ceratioid anglerfishes. Deep-sea anglerfish symbiont genomes are reduced in size by about 50% compared to free-living relatives. They show a striking convergence of genome reduction and loss of metabolic capabilities with a distinct lineage of obligately host-dependent luminous symbionts. These losses include reductions in amino acid synthesis pathways and abilities to utilize diverse sugars. However, the symbiont genomes have retained a number of categories of genes predicted to be useful only outside the host, such as those involved in chemotaxis and motility, suggesting that they may persist in the environment. These genomes contain very high numbers of pseudogenes and show massive expansions of transposable elements, with transposases accounting for 28 and 31% of coding sequences in the symbiont genomes. Transposon expansions appear to have occurred at different times in each symbiont lineage, indicating either independent evolutions of reduction or symbiont replacement. These results suggest ongoing genomic reduction in extracellular luminous symbionts that is facilitated by transposon proliferations.IMPORTANCE Many female deep-sea anglerfishes possess a &quot;lure&quot; containing luminous bacterial symbionts. Here we show that unlike most luminous symbionts, these bacteria are undergoing an evolutionary transition toward small genomes with limited metabolic capabilities. Comparative analyses of the symbiont genomes indicate that this transition is ongoing and facilitated by transposon expansions. This transition may have occurred independently in different symbiont lineages, although it is unclear why. Genomic reduction is common in bacteria that only live within host cells but less common in bacteria that, like anglerfish symbionts, live outside host cells. Since multiple evolutions of genomic reduction have occurred convergently in luminous bacteria, they make a useful system with which to understand patterns of genome evolution in extracellular symbionts. This work demonstrates that ecological factors other than an intracellular lifestyle can lead to dramatic gene loss and evolutionary changes and that transposon expansions may play important roles in this process.},
}
@article {pmid29944191,
year = {2018},
author = {Blackstone, NW and Golladay, JM},
title = {Why Do Corals Bleach? Conflict and Conflict Mediation in a Host/Symbiont Community.},
journal = {BioEssays : news and reviews in molecular, cellular and developmental biology},
volume = {40},
number = {8},
pages = {e1800021},
doi = {10.1002/bies.201800021},
pmid = {29944191},
issn = {1521-1878},
abstract = {Coral bleaching has attracted considerable study, yet one central question remains unanswered: given that corals and their Symbiodinium symbionts have co-evolved for millions of years, why does this clearly maladaptive process occur? Bleaching may result from evolutionary conflict between the host corals and their symbionts. Selection at the level of the individual symbiont favors using the products of photosynthesis for selfish replication, while selection at the higher level favors using these products for growth of the entire host/symbiont community. To hold the selfish lower-level units in check, mechanisms of conflict mediation must evolve. Fundamental features of photosynthesis have been co-opted into conflict mediation so that symbionts that fail to export these products produce high levels of reactive oxygen species and undergo programmed cell death. These mechanisms function very well under most environmental conditions, but under conditions particularly detrimental to photosynthesis, it is these mechanisms of conflict mediation that trigger bleaching.},
}
@article {pmid29944179,
year = {2018},
author = {Becquer, A and Garcia, K and Amenc, L and Rivard, C and Doré, J and Trives-Segura, C and Szponarski, W and Russet, S and Baeza, Y and Lassalle-Kaiser, B and Gay, G and Zimmermann, SD and Plassard, C},
title = {The Hebeloma cylindrosporum HcPT2 Pi transporter plays a key role in ectomycorrhizal symbiosis.},
journal = {The New phytologist},
volume = {220},
number = {4},
pages = {1185-1199},
doi = {10.1111/nph.15281},
pmid = {29944179},
issn = {1469-8137},
support = {20160232//SOLEIL/ ; 2010 BLAN 1604 03//ANR/ ; ANR-10-LABX-04-0//ANR/ ; //French Minister of Research and Technology/ ; //INRA (France)/ ; NIFA 2017-67014-26530//United States Department of Agriculture/ ; },
abstract = {Through a mutualistic relationship with woody plant roots, ectomycorrhizal fungi provide growth-limiting nutrients, including inorganic phosphate (Pi), to their host. Reciprocal trades occur at the Hartig net, which is the symbiotic interface of ectomycorrhizas where the two partners are symplasmically isolated. Fungal Pi must be exported to the symbiotic interface, but the proteins facilitating this transfer are unknown. In the present study, we combined transcriptomic, microscopy, whole plant physiology, X-ray fluorescence mapping, 32 P labeling and fungal genetic approaches to unravel the role of HcPT2, a fungal Pi transporter, during the Hebeloma cylindrosporum-Pinus pinaster ectomycorrhizal association. We localized HcPT2 in the extra-radical hyphae and the Hartig net and demonstrated its determinant role for both the establishment of ectomycorrhizas and Pi allocation towards P. pinaster. We showed that the host plant induces HcPT2 expression and that the artificial overexpression of HcPT2 is sufficient to significantly enhance Pi export towards the central cylinder. Together, our results reveal that HcPT2 plays an important role in ectomycorrhizal symbiosis, affecting both Pi influx in the mycelium and efflux towards roots under the control of P. pinaster.},
}
@article {pmid29943438,
year = {2018},
author = {Hester, ER},
title = {How a System of Checks on Symbiosis Could Become Disastrous.},
journal = {BioEssays : news and reviews in molecular, cellular and developmental biology},
volume = {40},
number = {8},
pages = {e1800106},
doi = {10.1002/bies.201800106},
pmid = {29943438},
issn = {1521-1878},
}
@article {pmid29942701,
year = {2018},
author = {Riascos, JM and Aguirre, W and Hopfe, C and Morales, D and Navarrete, Á and Tavera, J},
title = {Floating nurseries? Scyphozoan jellyfish, their food and their rich symbiotic fauna in a tropical estuary.},
journal = {PeerJ},
volume = {6},
number = {},
pages = {e5057},
doi = {10.7717/peerj.5057},
pmid = {29942701},
issn = {2167-8359},
abstract = {Background: The anthropogenic modification of trophic pathways is seemingly prompting the increase of jellyfish populations at the expense of planktivorous fishes. However, gross generalizations are often made because the most basic aspects of trophic ecology and the diverse interactions of jellyfish with fishes remain poorly described. Here we inquire on the dynamics of food consumption of the medusoid stage of the scyphozoan jellyfish Stomolophus meleagris and characterize the traits and diversity of its symbiotic community.<br><br>Methods: S. meleagris and their associated fauna were sampled in surface waters between November 2015 and April 2017 in Málaga Bay, an estuarine system at the Colombian Pacific. Stomach contents of medusae were examined and changes in prey composition and abundance over time analysed using a multivariate approach. The associated fauna was identified and the relationship between the size of medusae and the size those organisms tested using least-square fitting procedures.<br><br>Results: The presence of S. meleagris medusa in surface waters was seasonal. The gut contents analysis revealed that algae, copepods and fish early life stages were the more abundant items, and PERMANOVA analysis showed that the diet differed within the seasons (P(perm) = 0.001) but not between seasons (P(perm) = 0.134). The majority of the collected medusae (50.4%) were associated with individuals of 11 symbiotic species, 95.3% of them fishes, 3.1% crustaceans and 1.6% molluscs. Therefore, this study reports 10 previously unknown associations. The bell diameter of S. meleagris was positively related to the body sizes of their symbionts. However, a stronger fit was observed when the size relationship between S. meleagris and the fish Hemicaranx zelotes was modelled.<br><br>Discussion: The occurrence of S. meleagris was highly seasonal, and the observed patterns of mean body size through the seasons suggested the arrival of adult medusae to the estuary from adjacent waters. The diet of S. meleagris in the study area showed differences with previous reports, chiefly because of the abundance of algae that are seemingly ingested but not digested. The low number of zooplanktonic items in gut contents suggest the contribution of alternative food sources not easily identifiable. The observed changes in the composition of food in the guts probably reflect seasonal changes in the availability of prey items. The regular pattern in the distribution of symbionts among medusae (a single symbiont per host) and the positive host-symbiont size relationship reflects antagonistic intraspecific and interspecific behaviour of the symbiont. This strongly suggest that medusa represent an &quot;economically defendable resource&quot; that potentially increases the survival and recruitment of the symbionts to the adult population. We argue that, if this outcome of the symbiotic association can be proven, scyphozoan jellyfish can be regarded as floating nurseries.},
}
@article {pmid29941972,
year = {2018},
author = {Fiorilli, V and Vannini, C and Ortolani, F and Garcia-Seco, D and Chiapello, M and Novero, M and Domingo, G and Terzi, V and Morcia, C and Bagnaresi, P and Moulin, L and Bracale, M and Bonfante, P},
title = {Omics approaches revealed how arbuscular mycorrhizal symbiosis enhances yield and resistance to leaf pathogen in wheat.},
journal = {Scientific reports},
volume = {8},
number = {1},
pages = {9625},
doi = {10.1038/s41598-018-27622-8},
pmid = {29941972},
issn = {2045-2322},
abstract = {Besides improved mineral nutrition, plants colonised by arbuscular mycorrhizal (AM) fungi often display increased biomass and higher tolerance to biotic and abiotic stresses. Notwithstanding the global importance of wheat as an agricultural crop, its response to AM symbiosis has been poorly investigated. We focused on the role of an AM fungus on mineral nutrition of wheat, and on its potential protective effect against Xanthomonas translucens. To address these issues, phenotypical, molecular and metabolomic approaches were combined. Morphological observations highlighted that AM wheat plants displayed an increased biomass and grain yield, as well as a reduction in lesion area following pathogen infection. To elucidate the molecular mechanisms underlying the mycorrhizal phenotype, we investigated changes of transcripts and proteins in roots and leaves during the double (wheat-AM fungus) and tripartite (wheat-AM fungus-pathogen) interaction. Transcriptomic and proteomic profiling identified the main pathways involved in enhancing plant biomass, mineral nutrition and in promoting the bio-protective effect against the leaf pathogen. Mineral and amino acid contents in roots, leaves and seeds, and protein oxidation profiles in leaves, supported the omics data, providing new insight into the mechanisms exerted by AM symbiosis to confer stronger productivity and enhanced resistance to X. translucens in wheat.},
}
@article {pmid29940639,
year = {2018},
author = {Tamaş, C and Pintilie, CT and Atănăsoae, IV and Corduneanu, AM and Dabija, I and Olaru, FŞ and Hreniuc, IM and Tecuceanu, A and Munteanu, I and Dobre, C and Moraru, DC and Ianole, V and Tamaş, I and Costan, VV},
title = {Surgical reconstruction of post-tumoral facial defects.},
journal = {Romanian journal of morphology and embryology = Revue roumaine de morphologie et embryologie},
volume = {59},
number = {1},
pages = {285-291},
pmid = {29940639},
issn = {1220-0522},
mesh = {Carcinoma, Squamous Cell/pathology/*surgery ; Facial Neoplasms/pathology/*surgery ; Female ; Humans ; Male ; Reconstructive Surgical Procedures/*methods ; Retrospective Studies ; },
abstract = {PURPOSE: The face is an unfortunate location for any type of tumor - malignant or not - with significant esthetic and functional outcomes. To reconstruct a facial defect may seem simple, but can be rather complicated. The aim of this study is to analyze and discuss our results in order to conclude with specific surgical strategies correlated with the morphopathological results. The most important objective for us is to offer the highest level of expertise to our patients and to prove that the symbiosis between the surgical treatment and the work of the Department of Morphopathology is essential in order to maximize the quality of medical care provided for our patients.<br><br>A retrospective study was conducted on 116 patients diagnosed with facial malignant tumors, 70 of which were confirmed as basal cell carcinomas (BCCs), 35 confirmed as squamous cell carcinomas (SCCs) and 11 malignant melanomas (MMs). Most BCC cases (57) showed ulceration, with a long clinical evolution (more than 10 years) in 48 cases. Only in 12 SCC cases, patients showed inflammation and ulceration, with a shorter evolution period (2-5 years). For complete microscopic diagnosis, immunohistochemical (IHC) examination was necessary in 46 cases. The BCC &quot;deceiving&quot; clinical behavior and the generally aggressive character of the MM were found in our patients as well.<br><br>RESULTS: The most frequent sites were the orbital region (27 cases) and the nasolabial sulcus (26 cases). In order to reconstruct the postexcisional defects, we had to perform local flaps in 62 cases (14 frontal flaps for orbital defects, 32 glabellar flaps for medial epicanthus, lower lid and nasal region, 15 nasolabial flaps for lower lid or nasal alae and one &quot;Z&quot;-plasty for the submental region). Oncological follow-up was performed in all patients and in 15 cases re-excision was necessary (11 BCCs, two SCCs and two MMs). Cervical lymph node metastasis occurred in six cases (three BCCs, one SCC and two MMs).<br><br>CONCLUSIONS: The cooperation between surgeons and pathologists allowed for good outcomes and the pathology examination can guide the surgical approach towards better results both functionally and esthetically.},
}
@article {pmid29939816,
year = {2018},
author = {Guerrero-Galán, C and Garcia, K and Houdinet, G and Zimmermann, SD},
title = {HcTOK1 participates in the maintenance of K+ homeostasis in the ectomycorrhizal fungus Hebeloma cylindrosporum, which is essential for the symbiotic K+ nutrition of Pinus pinaster.},
journal = {Plant signaling &amp; behavior},
volume = {13},
number = {6},
pages = {e1480845},
doi = {10.1080/15592324.2018.1480845},
pmid = {29939816},
issn = {1559-2324},
abstract = {Most land plants rely on root symbioses to complement or improve their mineral nutrition. Recent researches have put forward that mycorrhizal fungi efficiently absorb and transfer potassium (K+) from the soil to host plant roots, but the molecular mechanisms involved are not completely elucidated yet. We have recently revealed that K+ is likely released from the fungal Hartig net to the plant by TOK channels in the ectomycorrhizal model Hebeloma cylindrosporum - Pinus pinaster. H. cylindrosporum harbours three TOK members. Herein, we report that one of them, HcTOK1, has similar features than the yeast ScTOK1. Moreover, we propose a role for this channel in the transport of K+ from the medium to ectomycorrhizal roots under K+ starvation.},
}
@article {pmid29938093,
year = {2018},
author = {Christian, N and Bever, JD},
title = {Carbon allocation and competition maintain variation in plant root mutualisms.},
journal = {Ecology and evolution},
volume = {8},
number = {11},
pages = {5792-5800},
doi = {10.1002/ece3.4118},
pmid = {29938093},
issn = {2045-7758},
abstract = {Plants engage in multiple root symbioses that offer varying degrees of benefit. We asked how variation in partner quality persists using a resource-ratio model of population growth. We considered the plant's ability to preferentially allocate carbon to mutualists and competition for plant carbon between mutualist and nonmutualist symbionts. We treated carbon as two nutritionally interchangeable, but temporally separated, resources-carbon allocated indiscriminately for the construction of the symbiosis, and carbon preferentially allocated to the mutualist after symbiosis establishment and assessment. This approach demonstrated that coexistence of mutualists and nonmutualists is possible when fidelity of the plant to the mutualist and the cost of mutualism mediate resource competition. Furthermore, it allowed us to trace symbiont population dynamics given varying degrees of carbon allocation. Specifically, coexistence occurs at intermediate levels of preferential allocation. Our findings are consistent with previous empirical studies as well the application of biological market theory to plantroot symbioses.},
}
@article {pmid29938062,
year = {2018},
author = {Bellis, ES and Edlund, RB and Berrios, HK and Lessios, HA and Denver, DR},
title = {Molecular signatures of host specificity linked to habitat specialization in Exaiptasia sea anemones.},
journal = {Ecology and evolution},
volume = {8},
number = {11},
pages = {5413-5426},
doi = {10.1002/ece3.4058},
pmid = {29938062},
issn = {2045-7758},
abstract = {Rising ocean temperatures associated with global climate change induce breakdown of the symbiosis between coelenterates and photosynthetic microalgae of the genus Symbiodinium. Association with more thermotolerant partners could contribute to resilience, but the genetic mechanisms controlling specificity of hosts for particular Symbiodinium types are poorly known. Here, we characterize wild populations of a sea anemone laboratory model system for anthozoan symbiosis, from contrasting environments in Caribbean Panama. Patterns of anemone abundance and symbiont diversity were consistent with specialization of holobionts for particular habitats, with Exaiptasia pallida/S. minutum (ITS2 type B1) abundant on vertical substrate in thermally stable, shaded environments but E. brasiliensis/Symbiodinium sp. (ITS2 clade A) more common in shallow areas subject to high temperature and irradiance. Population genomic sequencing revealed a novel E. pallida population from the Bocas del Toro Archipelago that only harbors S. minutum. Loci most strongly associated with divergence of the Bocas-specific population were enriched in genes with putative roles in cnidarian symbiosis, including activators of the complement pathway of the innate immune system, thrombospondin-type-1 repeat domain proteins, and coordinators of endocytic recycling. Our findings underscore the importance of unmasking cryptic diversity in natural populations and the role of long-term evolutionary history in mediating interactions with Symbiodinium.},
}
@article {pmid29937759,
year = {2018},
author = {Prihatna, C and Barbetti, MJ and Barker, SJ},
title = {A Novel Tomato Fusarium Wilt Tolerance Gene.},
journal = {Frontiers in microbiology},
volume = {9},
number = {},
pages = {1226},
doi = {10.3389/fmicb.2018.01226},
pmid = {29937759},
issn = {1664-302X},
abstract = {The reduced mycorrhizal colonization (rmc) tomato mutant is unable to form mycorrhiza and is more susceptible to Fusarium wilt compared with its wild-type isogenic line 76R. The rmc mutant has a chromosomal deletion affecting five genes, one of which is similar to CYCLOPS. Loss of this gene is responsible for non-mycorrhizality in rmc but not enhanced Fusarium wilt susceptibility. Here, we describe assessment of a second gene in the rmc deletion, designated Solyc08g075770 that is expressed in roots. Sequence analyses show that Solyc08g075770 encodes a small transmembrane protein with putative phosphorylation and glycosylation sites. It is predicted to be localized in the plasma membrane and may function in transmembrane ion transport and/or as a cell surface receptor. Complementation and knock-out strategies were used to test its function. Some putative CRISPR/Cas-9 knock-out transgenic events exhibited Fusarium wilt susceptibility like rmc and some putative complementation lines were 76R-like, suggesting that the tomato Solyc08g075770 functions in Fusarium wilt tolerance. This is the first study to demonstrate that Solyc08g075770 is the contributor to the Tfw locus, conferring tolerance to Fusarium wilt in 76R which was lost in rmc.},
}
@article {pmid29937485,
year = {2018},
author = {Uchida, Y and Irie, K and Fukuhara, D and Kataoka, K and Hattori, T and Ono, M and Ekuni, D and Kubota, S and Morita, M},
title = {Commensal Microbiota Enhance Both Osteoclast and Osteoblast Activities.},
journal = {Molecules (Basel, Switzerland)},
volume = {23},
number = {7},
pages = {},
doi = {10.3390/molecules23071517},
pmid = {29937485},
issn = {1420-3049},
mesh = {Alkaline Phosphatase/genetics/metabolism ; Animals ; Biomarkers/metabolism ; Bone Remodeling/*genetics ; Cathepsin K/genetics/metabolism ; Forkhead Transcription Factors/genetics/metabolism ; GATA3 Transcription Factor/genetics/metabolism ; Gastrointestinal Microbiome/*physiology ; Gene Expression Regulation ; *Germ-Free Life ; Insulin-Like Growth Factor I/genetics/metabolism ; Male ; Mice ; Nerve Tissue Proteins/genetics/metabolism ; Osteoblasts/cytology/*metabolism/microbiology ; Osteocalcin/genetics/metabolism ; Osteoclasts/cytology/*metabolism/microbiology ; Osteogenesis/*genetics ; Osteoprotegerin/genetics/metabolism ; RANK Ligand/genetics/metabolism ; Symbiosis/*physiology ; },
abstract = {Recent studies suggest that the commensal microbiota affects not only host energy metabolism and development of immunity but also bone remodeling by positive regulation of osteoclast activity. However, the mechanism of regulation of bone cells by the commensal microbiota has not been elucidated. In this study, 8-week-old specific pathogen-free (SPF) and germ-free (GF) mice were compared in terms of alveolar bones and primary osteoblasts isolated from calvarias. Micro-CT analysis showed that SPF mice had larger body size associated with lower bone mineral density and bone volume fraction in alveolar bones compared with GF mice. Greater numbers of osteoclasts in alveolar bone and higher serum levels of tartrate-resistant acid phosphatase 5b were observed in SPF mice. Tissue extracts from SPF alveolar bone showed higher levels of cathepsin K, indicating higher osteoclast activity. SPF alveolar extracts also showed elevated levels of &amp;gamma;-carboxylated glutamic acid⁻osteocalcin as a marker of mature osteoblasts compared with GF mice. Polymerase chain reaction (PCR) array analysis of RNA directly isolated from alveolar bone showed that in SPF mice, expression of mRNA of osteocalcin, which also acts as an inhibitor of bone mineralization, was strongly enhanced compared with GF mice. Cultured calvarial osteoblasts from SPF mice showed reduced mineralization but significantly enhanced expression of mRNAs of osteocalcin, alkaline phosphatase, insulin-like growth factor-I/II, and decreased ratio of osteoprotegerin/receptor activator of nuclear factor-kappa B ligand compared with GF mice. Furthermore, PCR array analyses of transcription factors in cultured calvarial osteoblasts showed strongly upregulated expression of Forkhead box g1. In contrast, Gata-binding protein 3 was strongly downregulated in SPF osteoblasts. These results suggest that the commensal microbiota prevents excessive mineralization possibly by stimulating osteocalcin expression in osteoblasts, and enhances both osteoblast and osteoclast activity by regulating specific transcription factors.},
}
@article {pmid29935536,
year = {2018},
author = {Toju, H and Tanabe, AS and Sato, H},
title = {Network hubs in root-associated fungal metacommunities.},
journal = {Microbiome},
volume = {6},
number = {1},
pages = {116},
doi = {10.1186/s40168-018-0497-1},
pmid = {29935536},
issn = {2049-2618},
abstract = {BACKGROUND: Although a number of recent studies have uncovered remarkable diversity of microbes associated with plants, understanding and managing dynamics of plant microbiomes remain major scientific challenges. In this respect, network analytical methods have provided a basis for exploring &quot;hub&quot; microbial species, which potentially organize community-scale processes of plant-microbe interactions.<br><br>METHODS: By compiling Illumina sequencing data of root-associated fungi in eight forest ecosystems across the Japanese Archipelago, we explored hubs within &quot;metacommunity-scale&quot; networks of plant-fungus associations. In total, the metadata included 8080 fungal operational taxonomic units (OTUs) detected from 227 local populations of 150 plant species/taxa.<br><br>RESULTS: Few fungal OTUs were common across all the eight forests. However, in each of the metacommunity-scale networks representing northern four localities or southern four localities, diverse mycorrhizal, endophytic, and pathogenic fungi were classified as &quot;metacommunity hubs,&quot; which were detected from diverse host plant taxa throughout a climatic region. Specifically, Mortierella (Mortierellales), Cladophialophora (Chaetothyriales), Ilyonectria (Hypocreales), Pezicula (Helotiales), and Cadophora (incertae sedis) had broad geographic and host ranges across the northern (cool-temperate) region, while Saitozyma/Cryptococcus (Tremellales/Trichosporonales) and Mortierella as well as some arbuscular mycorrhizal fungi were placed at the central positions of the metacommunity-scale network representing warm-temperate and subtropical forests in southern Japan.<br><br>CONCLUSIONS: The network theoretical framework presented in this study will help us explore prospective fungi and bacteria, which have high potentials for agricultural application to diverse plant species within each climatic region. As some of those fungal taxa with broad geographic and host ranges have been known to promote the survival and growth of host plants, further studies elucidating their functional roles are awaited.},
}
@article {pmid29935468,
year = {2018},
author = {Li, J and Sun, Y and Zhang, X and Hu, Y and Li, T and Zhang, X and Wang, Z and Wu, S and Wu, Z and Chen, B},
title = {A methyltransferase gene from arbuscular mycorrhizal fungi involved in arsenic methylation and volatilization.},
journal = {Chemosphere},
volume = {209},
number = {},
pages = {392-400},
doi = {10.1016/j.chemosphere.2018.06.092},
pmid = {29935468},
issn = {1879-1298},
mesh = {Arsenic/*chemistry/pharmacology ; Drug Resistance, Fungal ; Escherichia coli/drug effects ; Methylation ; Methyltransferases/genetics/*metabolism ; Mycorrhizae/*enzymology/genetics ; Plant Roots/*metabolism/microbiology ; Soil/chemistry ; Symbiosis ; *Volatilization ; },
abstract = {Arbuscular mycorrhizal fungi (AMF), ubiquitous symbiotic fungi associated with the majority of terrestrial plants, were demonstrated to play important roles in arsenic (As) translocation and transformation in the plant-soil continuum, and substantially influence plant As tolerance. However, the direct involvement of AMF in As methylation and volatilization and their molecular mechanisms remain unsolved. Here, an arsenite methyltransferase gene RiMT-11 was identified and characterized from AM fungus Rhizophagus irregularis. Heterologous expression of RiMT-11 enhanced arsenite resistance of E. coli (Δars) through methylating As into monomethylarsonic acid (MMA), dimethylarsinic acid (DMA) and ultimately volatile trimethyl arsine (TMAs). In a two-compartment in vitro monoxenic cultivation system, methylated and volatile As were also detected from AM symbioses with arsenate addition, accompanied by strong up-regulation of RiMT-11 expression in extraradical hyphae. The present study provided direct evidence and illustrated an underlying mechanism of As methylation and volatilization by AMF, leading to a deeper insight into the role of AMF in As biogeochemical cycling.},
}
@article {pmid29934334,
year = {2018},
author = {Judd, AM and Matthews, MK and Hughes, R and Veloz, M and Sexton, CE and Chaston, JM},
title = {Bacterial Methionine Metabolism Genes Influence Drosophila melanogaster Starvation Resistance.},
journal = {Applied and environmental microbiology},
volume = {84},
number = {17},
pages = {},
doi = {10.1128/AEM.00662-18},
pmid = {29934334},
issn = {1098-5336},
abstract = {Animal-associated microorganisms (microbiota) dramatically influence the nutritional and physiological traits of their hosts. To expand our understanding of such influences, we predicted bacterial genes that influence a quantitative animal trait by a comparative genomic approach, and we extended these predictions via mutant analysis. We focused on Drosophila melanogaster starvation resistance (SR). We first confirmed that D. melanogaster SR responds to the microbiota by demonstrating that bacterium-free flies have greater SR than flies bearing a standard 5-species microbial community, and we extended this analysis by revealing the species-specific influences of 38 genome-sequenced bacterial species on D. melanogaster SR. A subsequent metagenome-wide association analysis predicted bacterial genes with potential influence on D. melanogaster SR, among which were significant enrichments in bacterial genes for the metabolism of sulfur-containing amino acids and B vitamins. Dietary supplementation experiments established that the addition of methionine, but not B vitamins, to the diets significantly lowered D. melanogaster SR in a way that was additive, but not interactive, with the microbiota. A direct role for bacterial methionine metabolism genes in D. melanogaster SR was subsequently confirmed by analysis of flies that were reared individually with distinct methionine cycle Escherichia coli mutants. The correlated responses of D. melanogaster SR to bacterial methionine metabolism mutants and dietary modification are consistent with the established finding that bacteria can influence fly phenotypes through dietary modification, although we do not provide explicit evidence of this conclusion. Taken together, this work reveals that D. melanogaster SR is a microbiota-responsive trait, and specific bacterial genes underlie these influences.IMPORTANCE Extending descriptive studies of animal-associated microorganisms (microbiota) to define causal mechanistic bases for their influence on animal traits is an emerging imperative. In this study, we reveal that D. melanogaster starvation resistance (SR), a model quantitative trait in animal genetics, responds to the presence and identity of the microbiota. Using a predictive analysis, we reveal that the amino acid methionine has a key influence on D. melanogaster SR and show that bacterial methionine metabolism mutants alter normal patterns of SR in flies bearing the bacteria. Our data further suggest that these effects are additive, and we propose the untested hypothesis that, similar to bacterial effects on fruit fly triacylglyceride deposition, the bacterial influence may be through dietary modification. Together, these findings expand our understanding of the bacterial genetic basis for influence on a nutritionally relevant trait of a model animal host.},
}
@article {pmid29933518,
year = {2018},
author = {Rey, PJ and Cancio, I and Manzaneda, AJ and González-Robles, A and Valera, F and Salido, T and Alcántara, JM},
title = {Regeneration of a keystone semiarid shrub over its range in Spain: habitat degradation overrides the positive effects of plant-animal mutualisms.},
journal = {Plant biology (Stuttgart, Germany)},
volume = {20},
number = {6},
pages = {1083-1092},
doi = {10.1111/plb.12870},
pmid = {29933518},
issn = {1438-8677},
support = {CGL-2009-08130//MINECO/ ; RNM-766//Junta de Andalucía/ ; //European FEDER/ ; BES-2010-035999//FPI/ ; },
mesh = {Animals ; Demography ; Ecosystem ; Models, Statistical ; Rabbits/physiology ; Seed Dispersal/physiology ; Spain ; *Symbiosis ; Ziziphus/*physiology ; },
abstract = {Global change drivers are currently affecting semiarid ecosystems. Because these ecosystems differ from others in biotic and abiotic filters, cues for plant regeneration and management derived from elsewhere may not be applicable to semiarid ecosystems. We sought to determine the extent to which regional variation in regeneration prospects of a long-lived semiarid keystone shrub depends on anthropogenic habitat degradation, plant-animal interactions and climate determinants. We investigated the regeneration ability (via population size structure, juvenile density and juvenile/adult ratio), fruit set and seed dispersal of Ziziphus lotus in 25 localities spanning the range of its threatened habitats in Spain. We dissected the relative contribution of different regeneration determinants using multiple regression and structural equation modelling. Population regeneration was extremely poor, and size structures were biased towards large classes and low juvenile densities and juvenile/adult ratios. Poor regeneration was often coincident with seed dispersal collapse. However, the positive effect of seed dispersal on population regeneration disappeared after considering its relationship with habitat degradation. Protected areas did have juveniles. Together, these data suggest that habitat degradation directly impacts juvenile establishment. Our results provide insights into habitat and species management at the regional level. Z. lotus populations are currently driven by persistence-based dynamics through the longevity of the species. Nonetheless, collapsed seed dispersal, poor regeneration and the removal of adults from their habitats forecast extinction of Z. lotus in many remnants. The extreme longevity of Z. lotus provides opportunities for recovery of its populations and habitats through effective enforcement of regulations.},
}
@article {pmid29933190,
year = {2018},
author = {Tang, CC and Tian, Y and He, ZW and Zuo, W and Zhang, J},
title = {Performance and mechanism of a novel algal-bacterial symbiosis system based on sequencing batch suspended biofilm reactor treating domestic wastewater.},
journal = {Bioresource technology},
volume = {265},
number = {},
pages = {422-431},
doi = {10.1016/j.biortech.2018.06.033},
pmid = {29933190},
issn = {1873-2976},
mesh = {*Biofilms ; Bioreactors ; Chlorella ; Chlorophyll ; Nitrogen ; Phosphorus ; *Symbiosis ; Waste Disposal, Fluid ; *Waste Water ; },
abstract = {A novel algal-bacterial symbiosis system based on sequencing batch suspended biofilm reactor (A-SBSBR) was developed for simultaneously enhanced nitrogen (N) and phosphorus (P) removal from domestic wastewater. Results showed that the total N (TN) and P (TP) removal efficiencies in A-SBSBR increased to 69.91% and 94.78%, respectively. The mechanism analysis indicated that TN removal mainly occurred at non-aeration stage, and TP removal happened during the whole cycle in A-SBSBR. Compared to control SBSBR, TN removal by denitrification and anabolism and TP removal by anabolism in A-SBSBR increased by 12.70%, 7.64% and 50.13%, respectively. The Chlorophyll a accumulation in biofilm increased to 4.80 ± 0.08 mg/g. Algae related to Chlorella and Scenedesmus and bacteria related to Flavobacterium, Micropruina and Comamonadaceae were enriched in A-SBSBR and responsible for the enhanced nutrients removal effect. This study may provide a new solution to achieve nutrients removal enhancement from wastewater.},
}
@article {pmid29931403,
year = {2018},
author = {Lee, SJ and Kong, M and Morse, D and Hijri, M},
title = {Expression of putative circadian clock components in the arbuscular mycorrhizal fungus Rhizoglomus irregulare.},
journal = {Mycorrhiza},
volume = {},
number = {},
pages = {},
doi = {10.1007/s00572-018-0843-y},
pmid = {29931403},
issn = {1432-1890},
support = {RGPIN-2018-04178//Natural Sciences and Engineering Research Council of Canada/ ; },
abstract = {Arbuscular mycorrhizal fungi (AMF) are obligatory plant symbionts that live underground, so few studies have examined their response to light. Responses to blue light by other fungi can be mediated by White Collar-1 (WC-1) and WC-2 proteins. These wc genes, together with the frequency gene (frq), also form part of the endogenous circadian clock. The clock mechanism has never been studied in AMF, although circadian growth of their hyphae in the field has been reported. Using both genomic and transcriptomic data, we have found homologs of wc-1, wc-2, and frq and related circadian clock genes in the arbuscular mycorrhizal fungus Rhizoglomus irregulare (synonym Rhizophagus irregularis). Gene expression of wc-1, wc-2, and frq was analyzed using RT-qPCR on RNA extracted from germinating spores and from fungal material cultivated in vitro with transformed carrot roots. We found that all three core clock genes were expressed in both pre- and post-mycorrhizal stages of R. irregulare growth. Similar to the model fungus Neurospora crassa, the core circadian oscillator gene frq was induced by brief light stimulation. The presence of circadian clock and output genes in R. irregulare opens the door to the study of circadian clocks in the fungal partner of plant-AMF symbiosis. Our finding also provides new insight into the evolution of the circadian frq gene in fungi.},
}
@article {pmid29930569,
year = {2018},
author = {Lang, C and Smith, LS and Haney, CH and Long, SR},
title = {Corrigendum: Characterization of Novel Plant Symbiosis Mutants Using a New Multiple Gene-Expression Reporter Sinorhizobium meliloti Strain.},
journal = {Frontiers in plant science},
volume = {9},
number = {},
pages = {848},
doi = {10.3389/fpls.2018.00848},
pmid = {29930569},
issn = {1664-462X},
abstract = {[This corrects the article on p. 76 in vol. 9, PMID: 29467773.].},
}
@article {pmid29930051,
year = {2018},
author = {Murat, C and Kuo, A and Barry, KW and Clum, A and Dockter, RB and Fauchery, L and Iotti, M and Kohler, A and LaButti, K and Lindquist, EA and Lipzen, A and Morin, E and Wang, M and Grigoriev, IV and Zambonelli, A and Martin, FM},
title = {Draft Genome Sequence of Tuber borchii Vittad., a Whitish Edible Truffle.},
journal = {Genome announcements},
volume = {6},
number = {25},
pages = {},
doi = {10.1128/genomeA.00537-18},
pmid = {29930051},
issn = {2169-8287},
abstract = {The ascomycete Tuber borchii (Pezizomycetes) is a whitish edible truffle that establishes ectomycorrhizal symbiosis with trees and shrubs. This fungus is ubiquitous in Europe and is also cultivated outside Europe. Here, we present the draft genome sequence of T. borchii strain Tbo3840 (97.18 Mb in 969 scaffolds, with 12,346 predicted protein-coding genes).},
}
@article {pmid29928757,
year = {2018},
author = {Ye, Z and Vollhardt, IMG and Parth, N and Rubbmark, O and Traugott, M},
title = {Facultative bacterial endosymbionts shape parasitoid food webs in natural host populations: A correlative analysis.},
journal = {The Journal of animal ecology},
volume = {87},
number = {5},
pages = {1440-1451},
doi = {10.1111/1365-2656.12875},
pmid = {29928757},
issn = {1365-2656},
abstract = {Facultative bacterial endosymbionts can protect their aphid hosts from natural enemies such as hymenopteran parasitoids. As such, they have the capability to modulate interactions between aphids, parasitoids and hyperparasitoids. However, the magnitude of these effects in natural aphid populations and their associated parasitoid communities is currently unknown. Moreover, environmental factors such as plant fertilization and landscape complexity are known to affect aphid-parasitoid interactions but it remains unclear how such environmental factors affect the interplay between aphids, parasitoids and endosymbionts. Here, we tested whether facultative endosymbionts confer protection to parasitoids in natural populations of the English grain aphid, Sitobion avenae, and if this is affected by plant fertilization and landscape complexity. Furthermore, we examined whether the effects of facultative endosymbionts can cascade up to the hyperparasitoid level and increase primary-hyperparasitoid food web specialization. Living aphids and mummies were collected in fertilized and unfertilized plots within 13 wheat fields in Central Germany. We assessed the occurrence of primary parasitoid, hyperparasitoid and endosymbiont species in aphids and mummies using a newly established molecular approach. Facultative endosymbiont infection rates were high across fields (~80%), independent of whether aphids were parasitized or unparasitized. Aphid mummies exhibited a significantly lower share of facultative endosymbiont infection (~38%). These findings suggest that facultative endosymbionts do not affect parasitoid oviposition behaviour, but decrease parasitoid survival in the host. Facultative endosymbiont infection rates were lower in mummies collected from fertilized compared to unfertilized plants, indicating that plant fertilization boosts the facultative endosymbiont protective effect. Furthermore, we found strong evidence for species-specific and negative cascading effects of facultative endosymbionts on primary and hyperparasitoids, respectively. Facultative endosymbionts impacted parasitoid assemblages and increased the specialization of primary-hyperparasitoid food webs: these effects were independent from and much stronger than other environmental factors. The current findings strongly suggest that facultative endosymbionts act as a driving force in aphid-parasitoid-hyperparasitoid networks: they shape insect community composition at different trophic levels and modulate, directly and indirectly, the interactions between aphids, parasitoids and their environment.},
}
@article {pmid29928265,
year = {2018},
author = {Zhou, J and Richlen, ML and Sehein, TR and Kulis, DM and Anderson, DM and Cai, Z},
title = {Microbial Community Structure and Associations During a Marine Dinoflagellate Bloom.},
journal = {Frontiers in microbiology},
volume = {9},
number = {},
pages = {1201},
doi = {10.3389/fmicb.2018.01201},
pmid = {29928265},
issn = {1664-302X},
support = {P01 ES021923/ES/NIEHS NIH HHS/United States ; },
abstract = {Interactions between microorganisms and algae during bloom events significantly impacts their physiology, alters ambient chemistry, and shapes ecosystem diversity. The potential role these interactions have in bloom development and decline are also of particular interest given the ecosystem impacts of algal blooms. We hypothesized that microbial community structure and succession is linked to specific bloom stages, and reflects complex interactions among taxa comprising the phycosphere environment. This investigation used pyrosequencing and correlation approaches to assess patterns and associations among bacteria, archaea, and microeukaryotes during a spring bloom of the dinoflagellate Alexandrium catenella. Within the bacterial community, Gammaproteobacteria and Bacteroidetes were predominant during the initial bloom stage, while Alphaproteobacteria, Cyanobacteria, and Actinobacteria were the most abundant taxa present during bloom onset and termination. In the archaea biosphere, methanogenic members were present during the early bloom period while the majority of species identified in the late bloom stage were ammonia-oxidizing archaea and Halobacteriales. Dinoflagellates were the major eukaryotic group present during most stages of the bloom, whereas a mixed assemblage comprising diatoms, green-algae, rotifera, and other microzooplankton were present during bloom termination. Temperature and salinity were key environmental factors associated with changes in bacterial and archaeal community structure, respectively, whereas inorganic nitrogen and inorganic phosphate were associated with eukaryotic variation. The relative contribution of environmental parameters measured during the bloom to variability among samples was 35.3%. Interaction analysis showed that Maxillopoda, Spirotrichea, Dinoflagellata, and Halobacteria were keystone taxa within the positive-correlation network, while Halobacteria, Dictyochophyceae, Mamiellophyceae, and Gammaproteobacteria were the main contributors to the negative-correlation network. The positive and negative relationships were the primary drivers of mutualist and competitive interactions that impacted algal bloom fate, respectively. Functional predictions showed that blooms enhance microbial carbohydrate and energy metabolism, and alter the sulfur cycle. Our results suggest that microbial community structure is strongly linked to bloom progression, although specific drivers of community interactions and responses are not well understood. The importance of considering biotic interactions (e.g., competition, symbiosis, and predation) when investigating the link between microbial ecological behavior and an algal bloom's trajectory is also highlighted.},
}
@article {pmid29927925,
year = {2018},
author = {Estrela, S and Brown, SP},
title = {Community interactions and spatial structure shape selection on antibiotic resistant lineages.},
journal = {PLoS computational biology},
volume = {14},
number = {6},
pages = {e1006179},
doi = {10.1371/journal.pcbi.1006179},
pmid = {29927925},
issn = {1553-7358},
mesh = {Anti-Bacterial Agents/*pharmacology/therapeutic use ; *Bacteria/drug effects/pathogenicity ; Bacterial Infections/drug therapy/*microbiology ; Biofilms/drug effects ; Computational Biology ; Drug Resistance, Bacterial ; Humans ; *Microbial Interactions/drug effects/physiology ; *Models, Biological ; Symbiosis/drug effects/physiology ; },
abstract = {Polymicrobial interactions play an important role in shaping the outcome of antibiotic treatment, yet how multispecies communities respond to antibiotic assault is still little understood. Here we use an individual-based simulation model of microbial biofilms to investigate how competitive and mutualistic interactions between an antibiotic-resistant and a susceptible strain (or species) influence the two-lineage community response to antibiotic exposure. Our model predicts that while increasing competition and antibiotics leads to increasing competitive release of the antibiotic-resistant strain, hitting a mutualistic community of cross-feeding species with antibiotics leads to a mutualistic suppression effect where both susceptible and resistant species are harmed. We next show that the impact of antibiotics is further governed by emergent spatial feedbacks within communities. Mutualistic cross-feeding communities can rescue susceptible members by subsidizing their growth inside the biofilm despite lack of access to the nutrient-rich and high-antibiotic growing front. Moreover, we show that antibiotic detoxification by resistant cells can protect nearby susceptible cells, but such cross-protection is more effective in mutualistic communities because mutualism drives mixing of resistant and susceptible cells. In contrast, competition leads to segregation, which ultimately prevents susceptible cells to profit from detoxification. Understanding how the interplay between microbial metabolic interactions and community spatial structuring shapes the outcome of antibiotic treatment can be key to effectively leverage the power of antibiotics and promote microbiome health.},
}
@article {pmid29926944,
year = {2018},
author = {Chapple, ILC and Mealey, BL and Van Dyke, TE and Bartold, PM and Dommisch, H and Eickholz, P and Geisinger, ML and Genco, RJ and Glogauer, M and Goldstein, M and Griffin, TJ and Holmstrup, P and Johnson, GK and Kapila, Y and Lang, NP and Meyle, J and Murakami, S and Plemons, J and Romito, GA and Shapira, L and Tatakis, DN and Teughels, W and Trombelli, L and Walter, C and Wimmer, G and Xenoudi, P and Yoshie, H},
title = {Periodontal health and gingival diseases and conditions on an intact and a reduced periodontium: Consensus report of workgroup 1 of the 2017 World Workshop on the Classification of Periodontal and Peri-Implant Diseases and Conditions.},
journal = {Journal of periodontology},
volume = {89 Suppl 1},
number = {},
pages = {S74-S84},
doi = {10.1002/JPER.17-0719},
pmid = {29926944},
issn = {1943-3670},
abstract = {Periodontal health is defined by absence of clinically detectable inflammation. There is a biological level of immune surveillance that is consistent with clinical gingival health and homeostasis. Clinical gingival health may be found in a periodontium that is intact, i.e. without clinical attachment loss or bone loss, and on a reduced periodontium in either a non-periodontitis patient (e.g. in patients with some form of gingival recession or following crown lengthening surgery) or in a patient with a history of periodontitis who is currently periodontally stable. Clinical gingival health can be restored following treatment of gingivitis and periodontitis. However, the treated and stable periodontitis patient with current gingival health remains at increased risk of recurrent periodontitis, and accordingly, must be closely monitored. Two broad categories of gingival diseases include non-dental plaque biofilm-induced gingival diseases and dental plaque-induced gingivitis. Non-dental plaque biofilm-induced gingival diseases include a variety of conditions that are not caused by plaque and usually do not resolve following plaque removal. Such lesions may be manifestations of a systemic condition or may be localized to the oral cavity. Dental plaque-induced gingivitis has a variety of clinical signs and symptoms, and both local predisposing factors and systemic modifying factors can affect its extent, severity, and progression. Dental plaque-induced gingivitis may arise on an intact periodontium or on a reduced periodontium in either a non-periodontitis patient or in a currently stable &quot;periodontitis patient&quot; i.e. successfully treated, in whom clinical inflammation has been eliminated (or substantially reduced). A periodontitis patient with gingival inflammation remains a periodontitis patient (Figure 1), and comprehensive risk assessment and management are imperative to ensure early prevention and/or treatment of recurrent/progressive periodontitis. Precision dental medicine defines a patient-centered approach to care, and therefore, creates differences in the way in which a &quot;case&quot; of gingival health or gingivitis is defined for clinical practice as opposed to epidemiologically in population prevalence surveys. Thus, case definitions of gingival health and gingivitis are presented for both purposes. While gingival health and gingivitis have many clinical features, case definitions are primarily predicated on presence or absence of bleeding on probing. Here we classify gingival health and gingival diseases/conditions, along with a summary table of diagnostic features for defining health and gingivitis in various clinical situations.},
}
@article {pmid29926499,
year = {2018},
author = {Chapple, ILC and Mealey, BL and Van Dyke, TE and Bartold, PM and Dommisch, H and Eickholz, P and Geisinger, ML and Genco, RJ and Glogauer, M and Goldstein, M and Griffin, TJ and Holmstrup, P and Johnson, GK and Kapila, Y and Lang, NP and Meyle, J and Murakami, S and Plemons, J and Romito, GA and Shapira, L and Tatakis, DN and Teughels, W and Trombelli, L and Walter, C and Wimmer, G and Xenoudi, P and Yoshie, H},
title = {Periodontal health and gingival diseases and conditions on an intact and a reduced periodontium: Consensus report of workgroup 1 of the 2017 World Workshop on the Classification of Periodontal and Peri-Implant Diseases and Conditions.},
journal = {Journal of clinical periodontology},
volume = {45 Suppl 20},
number = {},
pages = {S68-S77},
doi = {10.1111/jcpe.12940},
pmid = {29926499},
issn = {1600-051X},
abstract = {Periodontal health is defined by absence of clinically detectable inflammation. There is a biological level of immune surveillance that is consistent with clinical gingival health and homeostasis. Clinical gingival health may be found in a periodontium that is intact, i.e. without clinical attachment loss or bone loss, and on a reduced periodontium in either a non-periodontitis patient (e.g. in patients with some form of gingival recession or following crown lengthening surgery) or in a patient with a history of periodontitis who is currently periodontally stable. Clinical gingival health can be restored following treatment of gingivitis and periodontitis. However, the treated and stable periodontitis patient with current gingival health remains at increased risk of recurrent periodontitis, and accordingly, must be closely monitored. Two broad categories of gingival diseases include non-dental plaque biofilm-induced gingival diseases and dental plaque-induced gingivitis. Non-dental plaque biofilm-induced gingival diseases include a variety of conditions that are not caused by plaque and usually do not resolve following plaque removal. Such lesions may be manifestations of a systemic condition or may be localized to the oral cavity. Dental plaque-induced gingivitis has a variety of clinical signs and symptoms, and both local predisposing factors and systemic modifying factors can affect its extent, severity, and progression. Dental plaque-induced gingivitis may arise on an intact periodontium or on a reduced periodontium in either a non-periodontitis patient or in a currently stable &quot;periodontitis patient&quot; i.e. successfully treated, in whom clinical inflammation has been eliminated (or substantially reduced). A periodontitis patient with gingival inflammation remains a periodontitis patient (Figure 1), and comprehensive risk assessment and management are imperative to ensure early prevention and/or treatment of recurrent/progressive periodontitis. Precision dental medicine defines a patient-centered approach to care, and therefore, creates differences in the way in which a &quot;case&quot; of gingival health or gingivitis is defined for clinical practice as opposed to epidemiologically in population prevalence surveys. Thus, case definitions of gingival health and gingivitis are presented for both purposes. While gingival health and gingivitis have many clinical features, case definitions are primarily predicated on presence or absence of bleeding on probing. Here we classify gingival health and gingival diseases/conditions, along with a summary table of diagnostic features for defining health and gingivitis in various clinical situations.},
}
@article {pmid29922515,
year = {2018},
author = {Quigley, KM and Strader, ME and Matz, MV},
title = {Relationship between Acropora millepora juvenile fluorescence and composition of newly established Symbiodinium assemblage.},
journal = {PeerJ},
volume = {6},
number = {},
pages = {e5022},
doi = {10.7717/peerj.5022},
pmid = {29922515},
issn = {2167-8359},
abstract = {Coral-dinoflagellate symbiosis is the key biological interaction enabling existence of modern-type coral reefs, but the mechanisms regulating initial host-symbiont attraction, recognition and symbiont proliferation thus far remain largely unclear. A common reef-building coral, Acropora millepora, displays conspicuous fluorescent polymorphism during all phases of its life cycle, due to the differential expression of fluorescent proteins (FPs) of the green fluorescent protein family. In this study, we examine whether fluorescent variation in young coral juveniles exposed to natural sediments is associated with the uptake of disparate Symbiodinium assemblages determined using ITS-2 deep sequencing. We found that Symbiodinium assemblages varied significantly when redness values varied, specifically in regards to abundances of clades A and C. Whether fluorescence was quantified as a categorical or continuous trait, clade A was found at higher abundances in redder juveniles. These preliminary results suggest juvenile fluorescence may be associated with Symbiodinium uptake, potentially acting as either an attractant to ecologically specific types or as a mechanism to modulate the internal light environment to control Symbiodinium physiology within the host.},
}
@article {pmid29922321,
year = {2018},
author = {Campos, P and Borie, F and Cornejo, P and López-Ráez, JA and López-García, Á and Seguel, A},
title = {Phosphorus Acquisition Efficiency Related to Root Traits: Is Mycorrhizal Symbiosis a Key Factor to Wheat and Barley Cropping?.},
journal = {Frontiers in plant science},
volume = {9},
number = {},
pages = {752},
doi = {10.3389/fpls.2018.00752},
pmid = {29922321},
issn = {1664-462X},
abstract = {Wheat (Triticum aestivum L.) and barley (Hordeum vulgare L.) are major crops cultivated around the world, thus playing a crucial role on human diet. Remarkably, the growing human population requires a significant increase in agricultural production in order to feed everybody. In this context, phosphorus (P) management is a key factor as it is component of organic molecules such as nucleic acids, ATP and phospholipids, and it is the most abundant macronutrient in biomass after nitrogen (N), although being one of the scarcest elements in the lithosphere. In general, P fertilization has low efficiency, as only a fraction of the applied P is acquired by roots, leaving a substantial amount to be accumulated in soil as not readily available P. Breeding for P-efficient cultivars is a relatively low cost alternative and can be done through two mechanisms: i) improving P use efficiency (PUE), and/or ii) P acquisition efficiency (PAE). PUE is related to the internal allocation/mobilization of P, and is usually represented by the amount of P accumulated per biomass. PAE relies on roots ability to acquire P from the soil, and is commonly expressed as the relative difference of P acquired under low and high P availability conditions. In this review, plant adaptations related to improved PAE are described, with emphasis on arbuscular mycorrhizal (AM) symbiosis, which is generally accepted to enhance plant P acquisition. A state of the art (1980-2018) of AM growth responses and P uptake in wheat and barley is made to discuss about the commonly accepted growth promoting effect and P increased uptake by AM fungi and the contrasting evidence about the generally accepted lack of positive responses in both plant species. Finally, the mechanisms by which AM symbiosis can affect wheat and barley PAE are discussed, highlighting the importance of considering AM functional diversity on future studies and the necessity to improve PAE definition by considering the carbon trading between all the directly related PAE traits and its return to the host plant.},
}
@article {pmid29922306,
year = {2018},
author = {Li, YY and Chen, XM and Zhang, Y and Cho, YH and Wang, AR and Yeung, EC and Zeng, X and Guo, SX and Lee, YI},
title = {Immunolocalization and Changes of Hydroxyproline-Rich Glycoproteins During Symbiotic Germination of Dendrobium officinale.},
journal = {Frontiers in plant science},
volume = {9},
number = {},
pages = {552},
doi = {10.3389/fpls.2018.00552},
pmid = {29922306},
issn = {1664-462X},
abstract = {Hydroxyproline-rich glycoproteins (HRGPs) are abundant cell wall components involved in mycorrhizal symbiosis, but little is known about their function in orchid mycorrhizal association. To gain further insight into the role of HRGPs in orchid symbiosis, the location and function of HRGPs were investigated during symbiotic germination of Dendrobium officinale. The presence of JIM11 epitope in developing protocorms was determined using immunodot blots and immunohistochemical staining procedures. Real-time PCR was also employed to verify the expression patterns of genes coding for extensin-like genes selected from the transcriptomic database. The importance of HRGPs in symbiotic germination was further investigated using 3,4-dehydro-L-proline (3,4-DHP), an inhibitor of HRGP biosynthesis. In symbiotic cultures, immunodot blots of JIM11 signals were moderate in mature seeds, and the signals became stronger in swollen embryos. After germination, signal intensities decreased in developing protocorms. In contrast, in asymbiotic cultures, JIM11 signals were much lower as compared with those stages in symbiotic cultures. Immunofluorescence staining enabled the visualization of JIM11 epitope in mature embryo and protocorm cells. Positive signals were initially localized in the larger cells near the basal (suspensor) end of uninfected embryos, marking the future colonization site of fungal hyphae. After 1 week of inoculation, the basal end of embryos had been colonized, and a strong signal was detected mostly at the mid- and basal regions of the enlarging protocorm. As protocorm development progressed, the signal was concentrated in the colonized cells at the basal end. In colonized cells, signals were present in the walls and intracellularly associated with hyphae and the pelotons. The precise localization of JIM11 epitope is further examined by immunogold labeling. In the colonized cells, gold particles were found mainly in the cell wall and the interfacial matrix near the fungal cell wall. Four extensin-like genes were verified to be highly up-regulated in symbiotically germinated protocorms as compared to asymbiotically germinated ones. The 3,4-DHP treatment inhibited the accumulation of HRGPs and symbiotic seed germination. In these protocorms, fungal hyphae could be found throughout the protocorms. Our results indicate that HRGPs play an important role in symbiotic germination. They can serve as markers for fungal colonization, establishing a symbiotic compartment and constraining fungal colonization inside the basal cells of protocorms.},
}
@article {pmid29921018,
year = {2018},
author = {Lamouche, F and Gully, D and Chaumeret, A and Nouwen, N and Verly, C and Pierre, O and Sciallano, C and Fardoux, J and Jeudy, C and Szücs, A and Mondy, S and Salon, C and Nagy, I and Kereszt, A and Dessaux, Y and Giraud, E and Mergaert, P and Alunni, B},
title = {Transcriptomic dissection of Bradyrhizobium sp. strain ORS285 in symbiosis with Aeschynomene spp. inducing different bacteroid morphotypes with contrasted symbiotic efficiency.},
journal = {Environmental microbiology},
volume = {},
number = {},
pages = {},
doi = {10.1111/1462-2920.14292},
pmid = {29921018},
issn = {1462-2920},
abstract = {To circumvent the paucity of nitrogen sources in the soil legume plants establish a symbiotic interaction with nitrogen-fixing soil bacteria called rhizobia. During symbiosis, the plants form root organs called nodules, where bacteria are housed intracellularly and become active nitrogen fixers known as bacteroids. Depending on their host plant, bacteroids can adopt different morphotypes, being either unmodified (U), elongated (E) or spherical (S). E- and S-type bacteroids undergo a terminal differentiation leading to irreversible morphological changes and DNA endoreduplication. Previous studies suggest that differentiated bacteroids display an increased symbiotic efficiency (E > U and S > U). In this study, we used a combination of Aeschynomene species inducing E- or S-type bacteroids in symbiosis with Bradyrhizobium sp. ORS285 to show that S-type bacteroids present a better symbiotic efficiency than E-type bacteroids. We performed a transcriptomic analysis on E- and S-type bacteroids formed by Aeschynomene afraspera and Aeschynomene indica nodules and identified the bacterial functions activated in bacteroids and specific to each bacteroid type. Extending the expression analysis in E- and S-type bacteroids in other Aeschynomene species by qRT-PCR on selected genes from the transcriptome analysis narrowed down the set of bacteroid morphotype-specific genes. Functional analysis of a selected subset of 31 bacteroid-induced or morphotype-specific genes revealed no symbiotic phenotypes in the mutants. This highlights the robustness of the symbiotic program but could also indicate that the bacterial response to the plant environment is partially anticipatory or even maladaptive. Our analysis confirms the correlation between differentiation and efficiency of the bacteroids and provides a framework for the identification of bacterial functions that affect the efficiency of bacteroids.© 2018 Society for Applied Microbiology and John Wiley &amp; Sons Ltd.},
}
@article {pmid29917104,
year = {2018},
author = {Celis, JS and Wibberg, D and Ramírez-Portilla, C and Rupp, O and Sczyrba, A and Winkler, A and Kalinowski, J and Wilke, T},
title = {Binning enables efficient host genome reconstruction in cnidarian holobionts.},
journal = {GigaScience},
volume = {7},
number = {7},
pages = {},
doi = {10.1093/gigascience/giy075},
pmid = {29917104},
issn = {2047-217X},
mesh = {Algorithms ; Animals ; Anthozoa/*physiology ; Cnidaria/*genetics ; Computational Biology ; Coral Reefs ; DNA/analysis ; Ecology ; *Genome ; Genomics/*methods ; High-Throughput Nucleotide Sequencing ; Metagenomics/*methods ; Phylogeny ; RNA, Ribosomal, 16S/analysis ; Sequence Analysis, DNA ; Symbiosis ; Transcriptome ; },
abstract = {Background: Many cnidarians, including stony corals, engage in complex symbiotic associations, comprising the eukaryotic host, photosynthetic algae, and highly diverse microbial communities-together referred to as holobiont. This taxonomic complexity makes sequencing and assembling coral host genomes extremely challenging. Therefore, previous cnidarian genomic projects were based on symbiont-free tissue samples. However, this approach may not be applicable to the majority of cnidarian species for ecological reasons. We therefore evaluated the performance of an alternative method based on sequence binning for reconstructing the genome of the stony coral Porites rus from a hologenomic sample and compared it to traditional approaches.<br><br>Results: Our results demonstrate that binning performs well for hologenomic data, producing sufficient reads for assembling the draft genome of P. rus. An assembly evaluation based on operational criteria showed results that were comparable to symbiont-free approaches in terms of completeness and usefulness, despite a high degree of fragmentation in our assembly. In addition, we found that binning provides sufficient data for exploratory k-mer estimation of genomic features, such as genome size and heterozygosity.<br><br>Conclusions: Binning constitutes a powerful approach for disentangling taxonomically complex coral hologenomes. Considering the recent decline of coral reefs on the one hand and previous limitations to coral genome sequencing on the other hand, binning may facilitate rapid and reliable genome assembly. This study also provides an important milestone in advancing binning from the metagenomic to the hologenomic and from the prokaryotic to the eukaryotic level.},
}
@article {pmid29915699,
year = {2018},
author = {Yeom, J and Nikitin, MA and Ivanenko, VN and Lee, W},
title = {A new minute ectosymbiotic harpacticoid copepod living on the sea cucumber Eupentacta fraudatrix in the East/Japan Sea.},
journal = {PeerJ},
volume = {6},
number = {},
pages = {e4979},
doi = {10.7717/peerj.4979},
pmid = {29915699},
issn = {2167-8359},
abstract = {The ectosymbiotic copepods, Vostoklaophonte eupenta gen. &amp; sp. nov. associated with the sea cucumber Eupentacta fraudatrix, was found in the subtidal zone of Peter the Great Bay, East/Japan Sea. The new genus, Vostoklaophonte, is similar to Microchelonia in the flattened body form, reduced mandible, maxillule and maxilla, but with well-developed prehensile maxilliped, and in the reduced segmentation and setation of legs 1-5. Most appendages of the new genus are more primitive than those of Microchelonia. The inclusion of the symbiotic genera Microchelonia and Vostoklaophonte gen. nov. in Laophontidae, as well as their close phylogenetic relationships, are supported by morphological observations and molecular data. This is the third record of laophontid harpacticoid copepods living in symbiosis with sea cucumbers recorded from the Korean and Californian coasts.},
}
@article {pmid29915605,
year = {2018},
author = {Jia, N and Zhu, Y and Xie, F},
title = {An Efficient Protocol for Model Legume Root Protoplast Isolation and Transformation.},
journal = {Frontiers in plant science},
volume = {9},
number = {},
pages = {670},
doi = {10.3389/fpls.2018.00670},
pmid = {29915605},
issn = {1664-462X},
abstract = {Transient gene expression systems using protoplasts have been widely used for rapid functional characterization of genes and high-throughput analysis in many model and crop species. Here, we describe a simplified and highly efficient root protoplast isolation and transient expression system in the model legumes Lotus japonicus and Medicago truncatula. Firstly, we presented an efficient protocol for isolating protoplasts from L. japonicus and M. truncatula roots. We then established an efficient transient expression system in these legumes root protoplasts. Using this protocol, the subcellular localization of two symbiosis related proteins (SYMRK and ERN1) were visualized in the plasma membrane and nuclei, respectively. Collectively, this efficient protoplast isolation and transformation protocol is sufficient for studies on protein subcellular localization, and should be suitable for many other molecular biology applications.},
}
@article {pmid29914365,
year = {2018},
author = {Kobayashi, Y and Maeda, T and Yamaguchi, K and Kameoka, H and Tanaka, S and Ezawa, T and Shigenobu, S and Kawaguchi, M},
title = {The genome of Rhizophagus clarus HR1 reveals a common genetic basis for auxotrophy among arbuscular mycorrhizal fungi.},
journal = {BMC genomics},
volume = {19},
number = {1},
pages = {465},
doi = {10.1186/s12864-018-4853-0},
pmid = {29914365},
issn = {1471-2164},
support = {JPMJAC1403//Accelerated Innovation Research Initiative Turning Top Science and Ideas into High-Impact Values/ ; },
abstract = {BACKGROUND: Mycorrhizal symbiosis is one of the most fundamental types of mutualistic plant-microbe interaction. Among the many classes of mycorrhizae, the arbuscular mycorrhizae have the most general symbiotic style and the longest history. However, the genomes of arbuscular mycorrhizal (AM) fungi are not well characterized due to difficulties in cultivation and genetic analysis. In this study, we sequenced the genome of the AM fungus Rhizophagus clarus HR1, compared the sequence with the genome sequence of the model species R. irregularis, and checked for missing genes that encode enzymes in metabolic pathways related to their obligate biotrophy.<br><br>RESULTS: In the genome of R. clarus, we confirmed the absence of cytosolic fatty acid synthase (FAS), whereas all mitochondrial FAS components were present. A KEGG pathway map identified the absence of genes encoding enzymes for several other metabolic pathways in the two AM fungi, including thiamine biosynthesis and the conversion of vitamin B6 derivatives. We also found that a large proportion of the genes encoding glucose-producing polysaccharide hydrolases, that are present even in ectomycorrhizal fungi, also appear to be absent in AM fungi.<br><br>CONCLUSIONS: In this study, we found several new genes that are absent from the genomes of AM fungi in addition to the genes previously identified as missing. Missing genes for enzymes in primary metabolic pathways imply that AM fungi may have a higher dependency on host plants than other biotrophic fungi. These missing metabolic pathways provide a genetic basis to explore the physiological characteristics and auxotrophy of AM fungi.},
}
@article {pmid29910665,
year = {2018},
author = {de Gier, W and Fransen, CHJM},
title = {Odontonia plurellicola sp. n. and Odontonia bagginsi sp. n., two new ascidian-associated shrimp from Ternate and Tidore, Indonesia, with a phylogenetic reconstruction of the genus (Crustacea, Decapoda, Palaemonidae).},
journal = {ZooKeys},
volume = {},
number = {765},
pages = {123-160},
doi = {10.3897/zookeys.765.25277},
pmid = {29910665},
issn = {1313-2989},
abstract = {Two new species of palaemonid shrimp associated with ascidian hosts, Odontonia bagginsisp. n. from Tidore and Odontonia plurellicolasp. n., from Ternate, Indonesia are described and figured. Through phylogenetic analyses based on both morphological and molecular datasets (mitochondrial Cytochrome c oxidase subunit I gene and the 16S mitochondrial ribosomal gene) of the genus Odontonia, the phylogenetic positions of the new species have been reconstructed. Scanning Electron Microscopy has been used to observe additional characters on dactyli of the ambulatory pereiopods. Odontonia plurellicolasp. n. appears to be more closely related to O. simplicipes and O. seychellensis, but it differs most notably in the morphology of the rostrum and mouthparts. Odontonia plurellicolasp. n. appears to be the only Odontonia species living inside a phlebobranch ascidian Plurella sp. Odontonia bagginsisp. n. is closely related to O. sibogae, but differs markedly in the abundance of setae on the propodi of the ambulatory pereiopods. In the present paper, O. maldivensis Fransen, 2006 is regarded as a junior synonym of O. rufopunctata Fransen, 2002 based on both morphological and molecular aspects.},
}
@article {pmid29910003,
year = {2018},
author = {Cossart, P and Delseny, M and Dujon, B},
title = {Symbiosis and cohabitation.},
journal = {Comptes rendus biologies},
volume = {341},
number = {5},
pages = {275},
doi = {10.1016/j.crvi.2018.06.001},
pmid = {29910003},
issn = {1768-3238},
}
@article {pmid29909554,
year = {2018},
author = {Hopkins, SR and McGregor, CM and Belden, LK and Wojdak, JM},
title = {Handling times and saturating transmission functions in a snail-worm symbiosis.},
journal = {Oecologia},
volume = {},
number = {},
pages = {},
doi = {10.1007/s00442-018-4206-3},
pmid = {29909554},
issn = {1432-1939},
support = {DEB-1501466//Division of Environmental Biology/ ; DEB-0918960//Division of Environmental Biology/ ; DEB-0918656//Division of Environmental Biology/ ; },
abstract = {All dynamic species interaction models contain an assumption that describes how contact rates scale with population density. Choosing an appropriate contact-density function is important, because different functions have different implications for population dynamics and stability. However, this choice can be challenging, because there are many possible functions, and most are phenomenological and thus difficult to relate to underlying ecological processes. Using one such phenomenological function, we described a nonlinear relationship between field transmission rates and host density in a common snail-oligochaete symbiosis. We then used a well-known contact function from predator-prey models, the Holling Type II functional response, to describe and predict host snail contact rates in the laboratory. The Holling Type II functional response accurately described both the nonlinear contact-density relationship and the average contact duration that we observed. Therefore, we suggest that contact rates saturate with host density in this system because each snail contact requires a non-instantaneous handling time, and additional possible contacts do not occur during that handling time. Handling times and nonlinear contact rates might also explain the nonlinear relationship between symbiont transmission and snail density that we observed in the field, which could be confirmed by future work that controls for other potential sources of seasonal variation in transmission rates. Because most animal contacts are not instantaneous, the Holling Type II functional response might be broadly relevant to diverse host-symbiont systems.},
}
@article {pmid29908997,
year = {2018},
author = {Ivanenko, VN and Hoeksema, BW and Mudrova, SV and Nikitin, MA and Martínez, A and Rimskaya-Korsakova, NN and Berumen, ML and Fontaneto, D},
title = {Lack of host specificity of copepod crustaceans associated with mushroom corals in the Red Sea.},
journal = {Molecular phylogenetics and evolution},
volume = {127},
number = {},
pages = {770-780},
doi = {10.1016/j.ympev.2018.06.024},
pmid = {29908997},
issn = {1095-9513},
abstract = {The radiation of symbiotic copepods (Crustacea: Copepoda) living in association with stony corals (Cnidaria: Scleractinia) is considered host-specific and linked to the phylogenetic diversification of their hosts. However, symbiotic copepods are poorly investigated, occurrence records are mostly anecdotal, and no explicit analysis exists regarding their relationship with the hosts. Here, we analysed the occurrence of symbiotic copepods on different co-occurring and phylogenetically closely related scleractinian corals. We used an innovative approach of DNA extraction from single microscopic specimens that preserves the shape of the organisms for integrative morphological studies. The rationale of the study involved: (i) sampling of mushroom corals (Fungiidae) belonging to 13 species and eight genera on different reefs along the Saudi coastline in the Red Sea, (ii) extraction of all the associated copepods, (iii) morphological screening and identification of copepod species, (iv) use of DNA taxonomy on mitochondrial and nuclear markers to determine species boundaries for morphologically unknown copepod species, (v) reconstruction of phylogenies to understand their evolutionary relationships, and (vi) analysis of the ecological drivers of the occurrence, diversity and host specificity of the copepods. The seven species of coral-associated copepods, all new to science, did not show any statistically significant evidence of host-specificity or other pattern of ecological association. We thus suggest that, contrary to most assumptions and previous anecdotal evidence on this coral-copepod host-symbiont system, the association between copepods and their host corals is rather labile, not strict, and not phylogenetically constrained, changing our perception on evolutionary patterns and processes in symbiotic copepods.},
}
@article {pmid29904061,
year = {2018},
author = {Srivastava, PL and Shukla, A and Kalunke, RM},
title = {Comprehensive metabolic and transcriptomic profiling of various tissues provide insights for saponin biosynthesis in the medicinally important Asparagus racemosus.},
journal = {Scientific reports},
volume = {8},
number = {1},
pages = {9098},
doi = {10.1038/s41598-018-27440-y},
pmid = {29904061},
issn = {2045-2322},
abstract = {Asparagus racemosus (Shatavari), belongs to the family Asparagaceae and is known as a &quot;curer of hundred diseases&quot; since ancient time. This plant has been exploited as a food supplement to enhance immune system and regarded as a highly valued medicinal plant in Ayurvedic medicine system for the treatment of various ailments such as gastric ulcers, dyspepsia, cardiovascular diseases, neurodegenerative diseases, cancer, as a galactogogue and against several other diseases. In depth metabolic fingerprinting of various parts of the plant led to the identification of 13 monoterpenoids exclusively present in roots. LC-MS profiling led to the identification of a significant number of steroidal saponins (33). However, we have also identified 16 triterpene saponins for the first time in A. racemosus. In order to understand the molecular basis of biosynthesis of major components, transcriptome sequencing from three different tissues (root, leaf and fruit) was carried out. Functional annotation of A. racemosus transcriptome resulted in the identification of 153 transcripts involved in steroidal saponin biosynthesis, 45 transcripts in triterpene saponin biosynthesis, 44 transcripts in monoterpenoid biosynthesis and 79 transcripts in flavonoid biosynthesis. These findings will pave the way for better understanding of the molecular basis of steroidal saponin, triterpene saponin, monoterpenoids and flavonoid biosynthesis in A. racemosus.},
}
@article {pmid29900606,
year = {2018},
author = {Vančurová, L and Muggia, L and Peksa, O and Řídká, T and Škaloud, P},
title = {The complexity of symbiotic interactions influences the ecological amplitude of the host: A case study in Stereocaulon (lichenized Ascomycota).},
journal = {Molecular ecology},
volume = {27},
number = {14},
pages = {3016-3033},
doi = {10.1111/mec.14764},
pmid = {29900606},
issn = {1365-294X},
abstract = {Symbiosis plays a fundamental role in nature. Lichens are among the best known, globally distributed symbiotic systems whose ecology is shaped by the requirements of all symbionts forming the holobiont. The widespread lichen-forming fungal genus Stereocaulon provides a suitable model to study the ecology of microscopic green algal symbionts (i.e., phycobionts) within the lichen symbiosis. We analysed 282 Stereocaulon specimens, collected in diverse habitats worldwide, using the algal ITS rDNA and actin gene sequences and fungal ITS rDNA sequences. Phylogenetic analyses revealed a great diversity among the predominant phycobionts. The algal genus Asterochloris (Trebouxiophyceae) was recovered in most