@article {pmid33471433,
year = {2021},
author = {Liu, J and Rasing, M and Zeng, T and Klein, J and Kulikova, O and Bisseling, T},
title = {NIN is essential for development of symbiosomes, suppression of defence and premature senescence in Medicago truncatula nodules.},
journal = {The New phytologist},
volume = {},
number = {},
pages = {},
doi = {10.1111/nph.17215},
pmid = {33471433},
issn = {1469-8137},
abstract = {NIN (NODULE INCEPTION) is a transcription factor that plays a key role during root nodule initiation. However, it's role in later nodule developmental stages is unclear. Both NIN mRNA and protein accumulated at the highest level in the proximal part of the infection zone in Medicago truncatula nodules. Two nin weak allele mutants, nin-13/16, form a rather normal nodule infection zone, whereas a fixation zone is not formed. Instead, a zone with defence responses and premature senescence occured and symbiosome development gets arrested. Mutations in nin-13/16 resulted in a truncated NIN lacking the conserved PB1 domain. However, this did not cause the nodule phenotype as nin mutants expressing NINΔPB1 formed wild-type-like nodule. The phenotype is likely caused by reduced NIN mRNA levels in the cytoplasm. Transcriptome analyses of nin-16 nodules showed that expression level of defence/senescence-related genes is markedly increased, whereas this of defence suppressing genes is reduced. Although defence/senescence seems well suppressed in the infection zone, the transcriptome is already markedly changed in the proximal part of infection zone. In addition to its function in infection and nodule organogenesis, NIN also plays a major role at the transition from infection to fixation zone in establishing a functional symbiosis.},
}
@article {pmid33468585,
year = {2021},
author = {Swaney, MH and Kalan, LR},
title = {Living in your Skin: Microbes, Molecules and Mechanisms.},
journal = {Infection and immunity},
volume = {},
number = {},
pages = {},
doi = {10.1128/IAI.00695-20},
pmid = {33468585},
issn = {1098-5522},
abstract = {Human skin functions as a physical, chemical, and immune barrier against the external environment, while also providing a protective niche for its resident microbiota, known as the skin microbiome. Cooperation between the microbiota, host skin cells, and the immune system is responsible for maintenance of skin health, and a disruption to this delicate balance, such as by pathogen invasion or a breach in the skin barrier, may lead to impaired skin function. In this minireview, we describe the role of the microbiome in microbe, host, and immune interactions under distinct skin states, including homeostasis, tissue repair, and wound infection. Furthermore, we highlight the growing number of diverse microbial metabolites and products that have been identified to mediate these interactions, particularly those involved in host-microbe communication and defensive symbiosis. We also address the contextual pathogenicity exhibited by many skin commensals and provide insight into future directions in the skin microbiome field.},
}
@article {pmid33467041,
year = {2021},
author = {Ingersoll, JG},
title = {Observations on the Occurrence, Transmission and Management of the COVID-19 Pandemic Derived from Physics.},
journal = {Diseases (Basel, Switzerland)},
volume = {9},
number = {1},
pages = {},
doi = {10.3390/diseases9010009},
pmid = {33467041},
issn = {2079-9721},
abstract = {Three important observations derived from the ongoing COVID-19 pandemic could result in the development of novel approaches to deal with it and avoid or at least minimize the occurrence and impact of future outbreaks. First, the dramatic increase in pandemics in the past decade alone suggests that the current relationship of humans with the environment is quickly becoming unstable, with potentially catastrophic consequences. In order to reduce the toll in life and property, we would need to shift our emphasis from control of nature to a symbiosis with nature. This, then, can become the new framework for dealing effectively with environmental issues such as climate change, whereby properly applied medical science would provide the necessary impetus for action. Second, the existence of superspreaders of infection among populations in this pandemic requires that we develop objective tests, most likely of a genetic nature, to identify them rather than apply indiscriminate and draconian controls across the board. Not identifying superspreaders in a timely fashion could allow this pandemic to turn into a black swan event, with a catastrophic impact on society. Third, we need to refocus our efforts in dealing with this pandemic from the virus itself to the human hosts. An objective morbidity risk index can be developed such that most of us can go about our daily business without the fear of becoming seriously ill, while measures can be implemented to protect those who are most vulnerable to this virus. These observations point clearly to a need for a paradigm shift.},
}
@article {pmid33466994,
year = {2021},
author = {Ferrier-Pagès, C and Martinez, S and Grover, R and Cybulski, J and Shemesh, E and Tchernov, D},
title = {Tracing the Trophic Plasticity of the Coral-Dinoflagellate Symbiosis Using Amino Acid Compound-Specific Stable Isotope Analysis.},
journal = {Microorganisms},
volume = {9},
number = {1},
pages = {},
doi = {10.3390/microorganisms9010182},
pmid = {33466994},
issn = {2076-2607},
abstract = {The association between corals and photosynthetic dinoflagellates is one of the most well-known nutritional symbioses, but nowadays it is threatened by global changes. Nutritional exchanges are critical to understanding the performance of this symbiosis under stress conditions. Here, compound-specific δ15N and δ13C values of amino acids (δ15NAA and δ13CAA) were assessed in autotrophic, mixotrophic and heterotrophic holobionts as diagnostic tools to follow nutritional interactions between the partners. Contrary to what was expected, heterotrophy was mainly traced through the δ15N of the symbiont's amino acids (AAs), suggesting that symbionts directly profit from host heterotrophy. The trophic index (TP) ranged from 1.1 to 2.3 from autotrophic to heterotrophic symbionts. In addition, changes in TP across conditions were more significant in the symbionts than in the host. The similar δ13C-AAs signatures of host and symbionts further suggests that symbiont-derived photosynthates are the main source of carbon for AAs synthesis. Symbionts, therefore, appear to be a key component in the AAs biosynthetic pathways, and might, via this obligatory function, play an essential role in the capacity of corals to withstand environmental stress. These novel findings highlight important aspects of the nutritional exchanges in the coral-dinoflagellates symbiosis. In addition, they feature δ15NAA as a useful tool for studies regarding the nutritional exchanges within the coral-symbiodiniaceae symbiosis.},
}
@article {pmid33462192,
year = {2021},
author = {Rajkumar, R and Régio Brambilla, C and Veselinović, T and Bierbrier, J and Wyss, C and Ramkiran, S and Orth, L and Lang, M and Rota Kops, E and Mauler, J and Scheins, J and Neumaier, B and Ermert, J and Herzog, H and Langen, KJ and Binkofski, FC and Lerche, C and Shah, NJ and Neuner, I},
title = {Excitatory-inhibitory balance within EEG microstates and resting-state fMRI networks: assessed via simultaneous trimodal PET-MR-EEG imaging.},
journal = {Translational psychiatry},
volume = {11},
number = {1},
pages = {60},
pmid = {33462192},
issn = {2158-3188},
abstract = {The symbiosis of neuronal activities and glucose energy metabolism is reflected in the generation of functional magnetic resonance imaging (fMRI) and electroencephalography (EEG) signals. However, their association with the balance between neuronal excitation and inhibition (E/I-B), which is closely related to the activities of glutamate and γ-aminobutyric acid (GABA) and the receptor availability (RA) of GABAA and mGluR5, remains unexplored. This research investigates these associations during the resting state (RS) condition using simultaneously recorded PET/MR/EEG (trimodal) data. The trimodal data were acquired from three studies using different radio-tracers such as, [11C]ABP688 (ABP) (N = 9), [11C]Flumazenil (FMZ) (N = 10) and 2-[18F]fluoro-2-deoxy-D-glucose (FDG) (N = 10) targeted to study the mGluR5, GABAA receptors and glucose metabolism respectively. Glucose metabolism and neuroreceptor binding availability (non-displaceable binding potential (BPND)) of GABAA and mGluR5 were found to be significantly higher and closely linked within core resting-state networks (RSNs). The neuronal generators of EEG microstates and the fMRI measures were most tightly associated with the BPND of GABAA relative to mGluR5 BPND and the glucose metabolism, emphasising a predominance of inhibitory processes within in the core RSNs at rest. Changes in the neuroreceptors leading to an altered coupling with glucose metabolism may render the RSNs vulnerable to psychiatric conditions. The paradigm employed here will likely help identify the precise neurobiological mechanisms behind these alterations in fMRI functional connectivity and EEG oscillations, potentially benefitting individualised healthcare treatment measures.},
}
@article {pmid33456099,
year = {2019},
author = {Vanlauwe, B and Hungria, M and Kanampiu, F and Giller, KE},
title = {The role of legumes in the sustainable intensification of African smallholder agriculture: Lessons learnt and challenges for the future.},
journal = {Agriculture, ecosystems & environment},
volume = {284},
number = {},
pages = {106583},
pmid = {33456099},
issn = {0167-8809},
abstract = {Grain legumes play a key role in smallholder farming systems in sub-Saharan Africa (SSA), in relation to food and nutrition security and income generation. Moreover, because of their N2-fixation capacity, such legumes can also have a positive influence on soil fertility. Notwithstanding many decades of research on the agronomy of grain legumes, their N2-fixation capacity, and their contribution to overall system productivity, several issues remain to be resolved to realize fully the benefits of grain legumes. In this paper we highlight major lessons learnt and expose key knowledge gaps in relation to grain legumes and their contributions to farming system productivity. The symbiosis between legumes and rhizobia forms the basis for its benefits and biological N2-fixation (BNF) relies as much on the legume genotype as on the rhizobial strains. As such, breeding grain legumes for BNF deserves considerably more attention. Even promiscuous varieties usually respond to inoculation, and as African soils contain a huge pool of unexploited biodiversity with potential to contribute elite rhizobial strains, strain selection should go hand-in-hand with legume breeding for N2-fixation. Although inoculated strains can outcompete indigenous strains, our understanding of what constitutes a good competitor is rudimentary, as well as which factors affect the persistence of inoculated rhizobia, which in its turn determines whether a farmer needs to re-inoculate each and every season. Although it is commonly assumed that indigenous rhizobia are better adapted to local conditions than elite strains used in inoculants, there is little evidence that this is the case. The problems of delivering inoculants to smallholders through poorly-developed supply chains in Africa necessitates inoculants based on sterile carriers with long shelf life. Other factors critical for a well-functioning symbiosis are also central to the overall productivity of grain legumes. Good agronomic practices, including the use of phosphorus (P)-containing fertilizer, improve legume yields though responses to inputs are usually very variable. In some situations, a considerable proportion of soils show no response of legumes to applied inputs, often referred to as non-responsive soils. Understanding the causes underlying this phenomenon is limited and hinders the uptake of legume agronomy practices. Grain legumes also contribute to the productivity of farming systems, although such effects are commonly greater in rotational than in intercropping systems. While most cropping systems allow for the integration of legumes, intercropped legumes provide only marginal benefits to associated crops. Important rotational benefits have been shown for most grain legumes though those with the highest N accumulation and lowest N harvest index appear to demonstrate higher residual benefits. N balance estimates often results in contradictory observations, mostly caused by the lack of understanding of belowground contributions of legumes to the N balance. Lastly, the ultimate condition for increased uptake of grain legumes by smallholder farmers lies in the understanding of how legume technologies and management practices can be tailored to the enormous diversity of agroecologies, farming systems, and smallholder farms in SSA. In conclusion, while research on grain legumes has revealed a number of important insights that will guide realization of the full potential of such legumes to the sustainable intensification of smallholder farming systems in SSA, many research challenges remain to be addressed to realize the full potential of BNF in these systems.},
}
@article {pmid33454544,
year = {2021},
author = {Soyano, T and Liu, M and Kawaguchi, M and Hayashi, M},
title = {Leguminous nodule symbiosis involves recruitment of factors contributing to lateral root development.},
journal = {Current opinion in plant biology},
volume = {59},
number = {},
pages = {102000},
doi = {10.1016/j.pbi.2020.102000},
pmid = {33454544},
issn = {1879-0356},
abstract = {Legumes and several plant species in the monophyletic nitrogen-fixing clade produce root nodules that function as symbiotic organs and establish mutualistic relationships with nitrogen-fixing bacteria. The modes of nodule organogenesis are distinct from those of lateral root development and also differ among different types of nodules formed in legumes and actinorhizal plants. It is considered that the evolution of new organs occurs through rearrangement of molecular networks interposed by certain neo-functionalized factors. Accumulating evidence has suggested that root nodule organogenesis involves root or lateral root developmental pathways. This review describes the current knowledge about the factors/pathways acquired by the common ancestor of the nitrogen-fixing clade in order to control nodule organogenesis.},
}
@article {pmid33459999,
year = {2021},
author = {Mazumdar, T and Teh, BS and Murali, A and Schmidt-Heck, W and Schlenker, Y and Vogel, H and Boland, W},
title = {Transcriptomics Reveal the Survival Strategies of Enterococcus mundtii in the Gut of Spodoptera littoralis.},
journal = {Journal of chemical ecology},
volume = {},
number = {},
pages = {},
pmid = {33459999},
issn = {1573-1561},
abstract = {The complex interaction between a higher organism and its resident gut flora is a subject of immense interest in the field of symbiosis. Many insects harbor a complex community of microorganisms in their gut. Larvae of Spodoptera littoralis, a lepidopteran pest, house a bacterial community that varies both spatially (along the length of the gut) and temporally (during the insect's life cycle). To monitor the rapid adaptation of microbes to conditions in the gut, a GFP-tagged reporter strain of E. mundtii, a major player in the gut community, was constructed. After early-instar S. littoralis larvae were fed with the tagged microbes, these were recovered from the larval fore- and hindgut by flow cytometry. The fluorescent reporter confirmed the persistence of E. mundtii in the gut. RNA-sequencing of the sorted bacteria highlighted various strategies of the symbiont's survival, including upregulated pathways for tolerating alkaline stress, forming biofilms and two-component signaling systems for quorum sensing, and resisting oxidative stress. Although these symbionts depend on the host for amino acid and fatty acids, differential regulation among various metabolic pathways points to an enriched lysine synthesis pathway of E. mundtii in the hindgut of the larvae.},
}
@article {pmid33455582,
year = {2021},
author = {Goffredi, SK and Motooka, C and Fike, DA and Gusmão, LC and Tilic, E and Rouse, GW and Rodríguez, E},
title = {Mixotrophic chemosynthesis in a deep-sea anemone from hydrothermal vents in the Pescadero Basin, Gulf of California.},
journal = {BMC biology},
volume = {19},
number = {1},
pages = {8},
pmid = {33455582},
issn = {1741-7007},
abstract = {BACKGROUND: Numerous deep-sea invertebrates, at both hydrothermal vents and methane seeps, have formed symbiotic associations with internal chemosynthetic bacteria in order to harness inorganic energy sources typically unavailable to animals. Despite success in nearly all marine habitats and their well-known associations with photosynthetic symbionts, Cnidaria remain one of the only phyla present in the deep-sea without a clearly documented example of dependence on chemosynthetic symbionts.
RESULTS: A new chemosynthetic symbiosis between the sea anemone Ostiactis pearseae and intracellular bacteria was discovered at ~ 3700 m deep hydrothermal vents in the southern Pescadero Basin, Gulf of California. Unlike most sea anemones observed from chemically reduced habitats, this species was observed in and amongst vigorously venting fluids, side-by-side with the chemosynthetic tubeworm Oasisia aff. alvinae. Individuals of O. pearseae displayed carbon, nitrogen, and sulfur tissue isotope values suggestive of a nutritional strategy distinct from the suspension feeding or prey capture conventionally employed by sea anemones. Molecular and microscopic evidence confirmed the presence of intracellular SUP05-related bacteria housed in the tentacle epidermis of O. pearseae specimens collected from 5 hydrothermally active structures within two vent fields ~ 2 km apart. SUP05 bacteria (Thioglobaceae) dominated the O. pearseae bacterial community, but were not recovered from other nearby anemones, and were generally rare in the surrounding water. Further, the specific Ostiactis-associated SUP05 phylotypes were not detected in the environment, indicating a specific association. Two unusual candidate bacterial phyla (the OD1 and BD1-5 groups) appear to associate exclusively with O. pearseae and may play a role in symbiont sulfur cycling.
CONCLUSION: The Cnidarian Ostiactis pearseae maintains a physical and nutritional alliance with chemosynthetic bacteria. The mixotrophic nature of this symbiosis is consistent with what is known about other cnidarians and the SUP05 bacterial group, in that they both form dynamic relationships to succeed in nature. The advantages gained by appropriating metabolic and structural resources from each other presumably contribute to their striking abundance in the Pescadero Basin, at the deepest known hydrothermal vents in the Pacific Ocean.},
}
@article {pmid33444551,
year = {2021},
author = {Mikaelyan, A},
title = {Beating Them with Their Own Stick-Tick Uses Amidase of Bacterial Origin as Part of Its Immune Arsenal.},
journal = {Cell host & microbe},
volume = {29},
number = {1},
pages = {1-3},
doi = {10.1016/j.chom.2020.12.019},
pmid = {33444551},
issn = {1934-6069},
mesh = {Amidohydrolases/genetics ; Animals ; Immunologic Factors ; *Ixodes ; Symbiosis ; Vertebrates ; },
abstract = {As vectors of microbial diseases in vertebrates, ticks are excellent at regulating bacterial proliferation in and around them. In a recent issue of Cell, Hayes et al. (2020) reveal acarid toxins of bacterial origin that help eliminate microbes that are pathogenic to black-legged ticks but commensal to their vertebrate hosts.},
}
@article {pmid32924759,
year = {2020},
author = {Han, F and He, X and Chen, W and Gai, H and Bai, X and He, Y and Takeshima, K and Ohwada, T and Wei, M and Xie, F},
title = {Involvement of a Novel TetR-Like Regulator (BdtR) of Bradyrhizobium diazoefficiens in the Efflux of Isoflavonoid Genistein.},
journal = {Molecular plant-microbe interactions : MPMI},
volume = {33},
number = {12},
pages = {1411-1423},
doi = {10.1094/MPMI-08-20-0243-R},
pmid = {32924759},
issn = {0894-0282},
mesh = {Bacterial Proteins/genetics/metabolism ; *Bradyrhizobium/drug effects/genetics/metabolism ; Gene Expression Regulation, Bacterial ; *Genistein/pharmacology ; *Soybeans/metabolism/microbiology ; Symbiosis ; },
abstract = {A wide variety of leguminous plant-released (iso)flavonoids, such as genistein, are potential inducers of the nodulation (nod) genes of endosymbiotic rhizobia for the production of Nod factors, which are vital signaling molecules for triggering the symbiotic process. However, these (iso)flavonoids are generally thought to be toxic to the bacterial partner to varying degrees. Here, a novel TetR-like regulator gene of the soybean symbiont Bradyrhizobium diazoefficiens USDA110, bdtR (systematic designation blr7023), was characterized. It was found to be rapidly and preferentially induced by genistein, and its mutation resulted in significantly increased expression of the neighboring bll7019-bll7021 genes, encoding a multidrug resistance efflux pump system, in the absence of this isoflavonoid. Then, the transcriptional start site of BdtR was determined, and it was revealed that BdtR acted as a transcriptional repressor of the above efflux system through the binding of an AT-rich operator, which could be completely prevented by genistein. In addition, the ΔbdtR deletion mutant strain showed higher accumulation of extracellular genistein and became less susceptible to the isoflavonoid. In contrast, the inactivation of BdtR led to the significantly decreased induction of a nodulation gene (nodY) independent of the expression of nodD1 and nodW and to much weaker nodulation competitiveness. Taken together, the results show that BdtR plays an early sensing role in maintaining the intracellular homeostasis of genistein, helping to alleviate its toxic effect on this bacterium by negatively regulating neighboring genes encoding an efflux pump system while being essentially required for nodule occupancy competitiveness.[Formula: see text] Copyright © 2020 The Author(s). This is an open access article distributed under the CC BY-NC-ND 4.0 International license.},
}
@article {pmid32514032,
year = {2020},
author = {Massa, N and Bona, E and Novello, G and Todeschini, V and Boatti, L and Mignone, F and Gamalero, E and Lingua, G and Berta, G and Cesaro, P},
title = {AMF communities associated to Vitis vinifera in an Italian vineyard subjected to integrated pest management at two different phenological stages.},
journal = {Scientific reports},
volume = {10},
number = {1},
pages = {9197},
pmid = {32514032},
issn = {2045-2322},
mesh = {*Farms ; *Host Microbial Interactions ; Italy ; Mycobiome/*physiology ; Mycorrhizae/*physiology ; *Pest Control ; Plant Roots/*physiology ; *Soil Microbiology ; *Symbiosis ; Vitis/*physiology ; },
abstract = {Vitis vinifera L. is an economically important crop that can be influenced by soil microorganisms, including arbuscular mycorrhizal fungi (AMF), that establish symbiotic associations with its roots. AMF have beneficial effects on grapevine performance improving water use efficiency and replant success. Most grapevine varieties are susceptible to various diseases, and integrated pest management (IPM) is one of the emerging approaches to perform pest control. In the present study, we examined the AMF communities present in the soil associated to the roots of V. vinifera cv. Pinot Noir (comparing them to those present in a soil not affected by grapevine roots), in a vineyard subjected to IPM at two different phenological stages, using 454 Roche sequencing technology. We proposed a new approach to analyze sequencing data. Most of the taxa were included in the family Glomeraceae. In particular, Glomus sp. Rhizophagus sp. and Septoglomus viscosum were present. The family Archeosporaceae was represented only by the genus Archeospora sp. Different AMF communities were found in the two soils and the importance of the phenological stage in regulating AMF biodiversity was assessed.},
}
@article {pmid32468805,
year = {2020},
author = {Hajnal-Jafari, T and Seman, V and Stamenov, D and Đurić, S},
title = {Effect of Chlorella vulgaris on Growth and Photosynthetic Pigment Content in Swiss Chard (Beta vulgaris L. subsp. cicla).},
journal = {Polish journal of microbiology},
volume = {69},
number = {},
pages = {1-4},
pmid = {32468805},
issn = {2544-4646},
mesh = {Agriculture/*methods ; Beta vulgaris/*physiology ; Chlorella vulgaris/*physiology ; Chlorophyll/*metabolism ; Chlorophyll A/*metabolism ; Photosynthesis/physiology ; Plant Leaves/anatomy & histology/chemistry ; Symbiosis ; },
abstract = {Microalgae application in agriculture is an alternative measure that could be highly beneficial to plants. The application of microalgae Chlorella vulgaris S45 and its effect on plant growth and pigment content in Swiss chard were investigated. In the treatments, 5% and 10% algal suspensions were applied by spraying on plants and in soil, respectively. C. vulgaris S45 affected the initial growth of Swiss chard and the content of photosynthetic pigments positively. The correlation analysis proved the existence of statistically significant interdependency between chlorophyll a (Chl a) content and leaf number (r = 0.876 at p < 0.05), and chlorophyll b (Chl b) content and fresh leaf weight (r = 0.783 at p < 0.05).
Microalgae application in agriculture is an alternative measure that could be highly beneficial to plants. The application of microalgae Chlorella vulgaris S45 and its effect on plant growth and pigment content in Swiss chard were investigated. In the treatments, 5% and 10% algal suspensions were applied by spraying on plants and in soil, respectively. C. vulgaris S45 affected the initial growth of Swiss chard and the content of photosynthetic pigments positively. The correlation analysis proved the existence of statistically significant interdependency between chlorophyll a (Chl a) content and leaf number (r = 0.876 at p < 0.05), and chlorophyll b (Chl b) content and fresh leaf weight (r = 0.783 at p < 0.05).},
}
@article {pmid32289261,
year = {2020},
author = {Huus, KE and Bauer, KC and Brown, EM and Bozorgmehr, T and Woodward, SE and Serapio-Palacios, A and Boutin, RCT and Petersen, C and Finlay, BB},
title = {Commensal Bacteria Modulate Immunoglobulin A Binding in Response to Host Nutrition.},
journal = {Cell host & microbe},
volume = {27},
number = {6},
pages = {909-921.e5},
doi = {10.1016/j.chom.2020.03.012},
pmid = {32289261},
issn = {1934-6069},
mesh = {Adult ; Animals ; Bacteria/genetics/*metabolism ; DNA-Binding Proteins/genetics ; Diet ; Feces/microbiology ; Gastrointestinal Microbiome/*immunology ; Homeostasis ; Host Microbial Interactions/*immunology ; Humans ; Immunoglobulin A/*immunology ; Inflammation ; Intestine, Small ; Lactobacillus/physiology ; Mice ; Mice, Knockout ; *Nutritional Status ; Polysaccharides ; Sugars/metabolism ; Symbiosis/*physiology ; },
abstract = {Immunoglobulin (Ig) A controls host-microbial homeostasis in the gut. IgA recognition of beneficial bacteria is decreased in acutely undernourished children, but the factors driving these changes in IgA targeting are unknown. Child undernutrition is a global health challenge that is exacerbated by poor sanitation and intestinal inflammation. To understand how nutrition impacts immune-microbe interactions, we used a mouse model of undernutrition with or without fecal-oral exposure and assessed IgA-bacterial targeting from weaning to adulthood. In contrast to healthy control mice, undernourished mice fail to develop IgA recognition of intestinal Lactobacillus. Glycan-mediated interactions between Lactobacillus and host antibodies are lost in undernourished mice due to rapid bacterial adaptation. Lactobacillus adaptations occur in direct response to nutritional pressure, independently of host IgA, and are associated with reduced mucosal colonization and with bacterial mutations in carbohydrate processing genes. Together these data indicate that diet-driven bacterial adaptations shape IgA recognition in the gut.},
}
@article {pmid32249540,
year = {2020},
author = {Zhou, J and Lin, ZJ and Cai, ZH and Zeng, YH and Zhu, JM and Du, XP},
title = {Opportunistic bacteria use quorum sensing to disturb coral symbiotic communities and mediate the occurrence of coral bleaching.},
journal = {Environmental microbiology},
volume = {22},
number = {5},
pages = {1944-1962},
doi = {10.1111/1462-2920.15009},
pmid = {32249540},
issn = {1462-2920},
support = {20180124085935704//Trade and Information Commission of Shenzhen/International ; JCYJ20170412171947159//NSFC/International ; JCYJ20170817160708491//NSFC/International ; JCYJ20170412171959157//NSFC/International ; },
mesh = {Acyl-Butyrolactones ; Aeromonas/metabolism ; Animals ; Anthozoa/*microbiology ; Bacteria/*metabolism ; Climate Change ; Coral Reefs ; Dysbiosis/*physiopathology ; Edwardsiella/metabolism ; Microbiota/*physiology ; Pseudomonas/metabolism ; Quorum Sensing/*physiology ; Seawater/microbiology ; Signal Transduction/physiology ; Symbiosis/physiology ; Vibrio/metabolism ; },
abstract = {Coral associated microorganisms, especially some opportunistic pathogens can utilize quorum-sensing (QS) signals to affect population structure and host health. However, direct evidence about the link between coral bleaching and dysbiotic microbiomes under QS regulation was lacking. Here, using 11 opportunistic bacteria and their QS products (AHLs, acyl-homoserine-lactones), we exposed Pocillopora damicornis to three different treatments: test groups (A and B: mixture of AHLs-producing bacteria and cocktail of AHLs signals respectively); control groups (C and D: group A and B with furanone added respectively); and a blank control (group E: only seawater) for 21 days. The results showed that remarkable bleaching phenomenon was observed in groups A and B. The operational taxonomic units-sequencing analysis shown that the bacterial network interactions and communities composition were significantly changed, becoming especially enhanced in the relative abundances of Vibrio, Edwardsiella, Enterobacter, Pseudomonas, and Aeromonas. Interestingly, the control groups (C and D) were found to have a limited influence upon host microbial composition and reduced bleaching susceptibility of P. damicornis. These results indicate bleaching's initiation and progression may be caused by opportunistic bacteria of resident microbes in a process under regulation by AHLs. These findings add a new dimension to our understanding of the complexity of bleaching mechanisms from a chemoecological perspective.},
}
@article {pmid31943674,
year = {2020},
author = {Matthews, JL and Raina, JB and Kahlke, T and Seymour, JR and van Oppen, MJH and Suggett, DJ},
title = {Symbiodiniaceae-bacteria interactions: rethinking metabolite exchange in reef-building corals as multi-partner metabolic networks.},
journal = {Environmental microbiology},
volume = {22},
number = {5},
pages = {1675-1687},
doi = {10.1111/1462-2920.14918},
pmid = {31943674},
issn = {1462-2920},
support = {DP180100074//Australian Research Council/International ; DP180100838//Australian Research Council/International ; FL180100036//Australian Research Council/International ; LT000625/2018‐L//Human Frontier Science Program/International ; },
mesh = {Animals ; Anthozoa/*microbiology ; Archaea/*metabolism ; Bacteria/genetics/*metabolism ; Coral Reefs ; Dinoflagellida/*microbiology ; Ecosystem ; Fungi/genetics/*metabolism ; Metabolic Networks and Pathways ; Symbiosis/*physiology ; },
abstract = {The intimate relationship between scleractinian corals and their associated microorganisms is fundamental to healthy coral reef ecosystems. Coral-associated microbes (Symbiodiniaceae and other protists, bacteria, archaea, fungi and viruses) support coral health and resilience through metabolite transfer, inter-partner signalling, and genetic exchange. However, much of our understanding of the coral holobiont relationship has come from studies that have investigated either coral-Symbiodiniaceae or coral-bacteria interactions in isolation, while relatively little research has focused on other ecological and metabolic interactions potentially occurring within the coral multi-partner symbiotic network. Recent evidences of intimate coupling between phytoplankton and bacteria have demonstrated that obligate resource exchange between partners fundamentally drives their ecological success. Here, we posit that similar associations with bacterial consortia regulate Symbiodiniaceae productivity and are in turn central to the health of corals. Indeed, we propose that this bacteria-Symbiodiniaceae-coral relationship underpins the coral holobiont's nutrition, stress tolerance and potentially influences the future survival of coral reef ecosystems under changing environmental conditions. Resolving Symbiodiniaceae-bacteria associations is therefore a logical next step towards understanding the complex multi-partner interactions occurring in the coral holobiont.},
}
@article {pmid33453317,
year = {2021},
author = {Slijepcevic, P},
title = {Serial Endosymbiosis Theory: From biology to astronomy and back to the origin of life.},
journal = {Bio Systems},
volume = {},
number = {},
pages = {104353},
doi = {10.1016/j.biosystems.2021.104353},
pmid = {33453317},
issn = {1872-8324},
abstract = {Serial Endosymbiosis Theory, or SET, was conceived and developed by Lynn Margulis, to explain the greatest discontinuity in the history of life, the origin of eukaryotic cells. Some predictions of SET, namely the origin of mitochondria and chloroplasts, withstood the test of the most recent evidence from a variety of disciplines including phylogenetics, biochemistry, and cell biology. Even though some other predictions fared less well, SET remains a seminal theory in biology. In this paper, I focus on two aspects of SET. First, using the concept of "universal symbiogenesis", developed by Freeman Dyson to search for commonalities in astronomy and biology, I propose that SET can be extended beyond eukaryogenesis. The extension refers to the possibility that even prokaryotic organisms, themselves subject to the process of symbiogenesis in SET, could have emerged symbiotically. Second, I contrast a recent "viral eukaryogenesis" hypothesis, according to which the nucleus evolved from a complex DNA virus, with a view closer to SET, according to which the nucleus evolved through the interplay of the archaeal host, the eubacterial symbiont, and a non-LTR transposon, or telomerase. Viruses joined in later, through the process of viral endogenization, to shape eukaryotic chromosomes in the process of karyotype evolution. These two proposals based on SET are a testament to its longevity as a scientific theory.},
}
@article {pmid33453107,
year = {2021},
author = {Matamoros, MA and Becana, M},
title = {Molecular responses of legumes to abiotic stress: protein post-translational modifications and redox signaling.},
journal = {Journal of experimental botany},
volume = {},
number = {},
pages = {},
doi = {10.1093/jxb/erab008},
pmid = {33453107},
issn = {1460-2431},
abstract = {Legumes include several major crops that are able to fix atmospheric nitrogen in symbiotic root nodules, thus reducing the demand for nitrogen fertilizers and contributing to sustainable agriculture. Global change models predict increases in temperature and more extreme weather conditions. This scenario might increase plant exposure to abiotic stresses and negatively affect crop production. Regulation of whole-plant physiology and nitrogen fixation in legumes during abiotic stress is complex and only a few mechanisms have been elucidated. Reactive oxygen (ROS), nitrogen (RNS), and sulfur (RSS) species are key players in the acclimation and stress tolerance of plants. However, the specific redox-dependent signaling pathways are far from understood. One mechanism by which ROS, RNS, and RSS fulfil their signaling role is the post-translational modification (PTM) of proteins. Redox-based PTMs mostly occur in the cysteine thiol group (oxidation, S-nitrosylation, S-glutathionylation, persulfidation), but also in methionine (oxidation), tyrosine (nitration), and lysine and arginine (carbonylation/glycation) residues. Unraveling PTM patterns under different types of stress and establishing the functional implications may reveal so far unknown underlying mechanisms of the plant and nodule responses to adverse conditions. Here we review the current knowledge on redox PTMs in legumes and their possible consequences in plant and nodule biology.},
}
@article {pmid33452487,
year = {2021},
author = {Zhang, B and Wang, M and Sun, Y and Zhao, P and Liu, C and Qing, K and Hu, X and Zhong, Z and Cheng, J and Wang, H and Peng, Y and Shi, J and Zhuang, L and Du, S and He, M and Wu, H and Liu, M and Chen, S and Wang, H and Chen, X and Fan, W and Tian, K and Wang, Y and Chen, Q and Wang, S and Dong, F and Yang, C and Zhang, M and Song, Q and Li, Y and Wang, X},
title = {Glycine max NNL1 restricts symbiotic compatibility with widely distributed bradyrhizobia via root hair infection.},
journal = {Nature plants},
volume = {7},
number = {1},
pages = {73-86},
pmid = {33452487},
issn = {2055-0278},
abstract = {Symbiosis between soybean (Glycine max) and rhizobia is essential for efficient nitrogen fixation. Rhizobial effectors secreted through the type-III secretion system are key for mediating the interactions between plants and rhizobia, but the molecular mechanism remains largely unknown. Here, our genome-wide association study for nodule number identified G. max Nodule Number Locus 1 (GmNNL1), which encodes a new R protein. GmNNL1 directly interacts with the nodulation outer protein P (NopP) effector from Bradyrhizobium USDA110 to trigger immunity and inhibit nodulation through root hair infection. The insertion of a 179 bp short interspersed nuclear element (SINE)-like transposon into GmNNL1 leads to the loss of function of GmNNL1, enabling bradyrhizobia to successfully nodulate soybeans through the root hair infection route and enhancing nitrogen fixation. Our findings provide important insights into the coevolution of soybean-bradyrhizobia compatibility and offer a way to design new legume-rhizobia interactions for efficient symbiotic nitrogen fixation.},
}
@article {pmid33452473,
year = {2021},
author = {Rouzé, H and Galand, PE and Medina, M and Bongaerts, P and Pichon, M and Pérez-Rosales, G and Torda, G and Moya, A and , and Raina, JB and Hédouin, L},
title = {Symbiotic associations of the deepest recorded photosynthetic scleractinian coral (172 m depth).},
journal = {The ISME journal},
volume = {},
number = {},
pages = {},
pmid = {33452473},
issn = {1751-7370},
abstract = {The symbiosis between scleractinian corals and photosynthetic algae from the family Symbiodiniaceae underpins the health and productivity of tropical coral reef ecosystems. While this photosymbiotic association has been extensively studied in shallow waters (<30 m depth), we do not know how deeper corals, inhabiting large and vastly underexplored mesophotic coral ecosystems, modulate their symbiotic associations to grow in environments that receive less than 1% of surface irradiance. Here we report on the deepest photosymbiotic scleractinian corals collected to date (172 m depth), and use amplicon sequencing to identify the associated symbiotic communities. The corals, identified as Leptoseris hawaiiensis, were confirmed to host Symbiodiniaceae, predominantly of the genus Cladocopium, a single species of endolithic algae from the genus Ostreobium, and diverse communities of prokaryotes. Our results expand the reported depth range of photosynthetic scleractinian corals (0-172 m depth), and provide new insights on their symbiotic associations at the lower depth extremes of tropical coral reefs.},
}
@article {pmid33450718,
year = {2021},
author = {Berger, F and Gutjahr, C},
title = {Factors affecting plant responsiveness to arbuscular mycorrhiza.},
journal = {Current opinion in plant biology},
volume = {59},
number = {},
pages = {101994},
doi = {10.1016/j.pbi.2020.101994},
pmid = {33450718},
issn = {1879-0356},
abstract = {Arbuscular mycorrhiza (AM) is an ancient, widespread symbiosis between most land plants and fungi of the Glomeromycotina, which receives increasing interest for agricultural application because it can promote plant growth and yield. The ability of plants to react to AM with changes in morphology and/or performance in terms of yield is called 'AM responsiveness'. Its amplitude depends on the plant- fungal genotype combination and the abiotic and biotic environment. A molecular understanding of AM responsiveness is key for enabling rational application of AM in agriculture, for example through targeted breeding of AM-optimised crops. However, the genetic and mechanistic underpinnings of AM responsiveness variation remain still unknown. Here, we review current knowledge on AM responsiveness, with a focus on agricultural crops, and speculate on mechanisms that may contribute to the variation in AM response.},
}
@article {pmid33450673,
year = {2020},
author = {Kuhikar, R and Khan, N and Khare, SP and Fulzele, A and Melinkeri, S and Kale, V and Limaye, L},
title = {Neutrophils generated in vitro from hematopoietic stem cells isolated from apheresis samples and umbilical cord blood form neutrophil extracellular traps.},
journal = {Stem cell research},
volume = {50},
number = {},
pages = {102150},
doi = {10.1016/j.scr.2020.102150},
pmid = {33450673},
issn = {1876-7753},
abstract = {Neutrophils release neutrophil extracellular traps (NET) comprising of decondensed chromatin that immobilizes and kills pathogens. In vitro generation of neutrophils on a large scale from hematopoietic stem cells (HSCs) may be a useful strategy for treating neutropenic patients in future, though it is not in clinical practice yet. Microbial infections lead to major cause of morbidity and mortality in these patients. Despite the importance of NET in preventing infection, efficacy of in vitro-generated neutrophils from HSCs to form NET is not tested. We show that functional neutrophils could be generated in vitro from HSCs/MNCs isolated from umbilical cord blood (UCB) and apheresis-derived peripheral blood (APBL). Neutrophils generated from UCB showed properties comparable to those isolated from peripheral blood. We also show that isolation of HSCs is not absolutely essential for in vitro neutrophil generation. Further, we show that neutrophils generated from HSCs express PADI4 enzyme and their NET-forming ability is comparable to peripheral blood neutrophils. Taken together, our data show that fully functional neutrophils can be generated in vitro from HSCs. NET-forming ability of in vitro-generated neutrophils is an important parameter to determine their functionality and thus, should be studied along with other standard functional assays.},
}
@article {pmid33450310,
year = {2021},
author = {Widyarman, AS and Udawatte, NS and Theodorea, CF and Apriani, A and Richi, M and Astoeti, TE and Seneviratne, CJ},
title = {Casein phosphopeptide-amorphous calcium phosphate fluoride treatment enriches the symbiotic dental plaque microbiome in children.},
journal = {Journal of dentistry},
volume = {},
number = {},
pages = {103582},
doi = {10.1016/j.jdent.2021.103582},
pmid = {33450310},
issn = {1879-176X},
abstract = {OBJECTIVES: The dysbiotic oral microbiome plays a key role in the pathogenesis of caries in children. Topical application of casein phosphopeptide-amorphous calcium phosphate containing fluoride (CPP-ACP/F) is an effective treatment modality for children with caries (CC). Hitherto the mechanism by which CPP-ACP/F modules the oral microbiome in CC has not been investigated. The study aimed to examine the CPP-ACP/F effect on the dental plaque microbiome of children group with caries.
METHODS: This preliminary prospective clinical cohort included 10 children with caries. The children received topical fluoride CPP-ACP/F once-a-week for one month. Plaque samples were collected before and after treatment and subjected to 16S rDNA-based next-generation-sequencing. Microbial composition, diversity and functional roles were analyzed in comparison to the clinical characteristics of cohort using standard bioinformatics tools.
RESULTS: CPP-ACP/F treatment modulated dysbiotic oral microbiome towards healthier community as the higher proportion of Proteobacteria and certain microbial protective species were enriched following CPP-ACP/F treatment. Despite overall uniformity of community structure in children with caries between the groups, some bacterial species were differentially represented in a statistically significant manner between pre- and post- treatments. Three bacterial species were found to be predictive of strongly sensitive to the CPP-ACP/F treatment, marked by decreased abundance of Lautropia mirabalis and increased abundance of Gemella haemolysans and Schwartzia succinivorans.
CONCLUSION: Within the limits of the current study, it could be concluded that the CPP-ACP/F varnish treatment modulated the microbial composition of the dental plaque microbiome towards symbiosis. These symbiotic changes may demonstrate the potential clinical significance of CPP-ACP/F varnish treatment.},
}
@article {pmid33448795,
year = {2021},
author = {Borah, R and Ingavle, GC and Kumar, A and Sandeman, SR and Mikhalovsky, SV},
title = {Surface-Functionalized Conducting Nanofibers for Electrically Stimulated Neural Cell Function.},
journal = {Biomacromolecules},
volume = {},
number = {},
pages = {},
doi = {10.1021/acs.biomac.0c01445},
pmid = {33448795},
issn = {1526-4602},
abstract = {Strategies involving the inclusion of cell-instructive chemical and topographical cues to smart biomaterials in combination with a suitable physical stimulus may be beneficial to enhance nerve-regeneration rate. In this regard, we investigated the surface functionalization of poly[2-methoxy-5-(2-ethylhexyloxy)-1,4-phenylenevinylene] (MEH-PPV)-based electroconductive electrospun nanofibers coupled with externally applied electrical stimulus for accelerated neuronal growth potential. In addition, the voltage-dependent conductive mechanism of the nanofibers was studied in depth to interlink intrinsic conductive properties with electrically stimulated neuronal expressions. Surface functionalization was accomplished using 3-aminopropyltriethoxysilane (APTES) and 1,6-hexanediamine (HDA) as an alternative to costly biomolecule coating (e.g., collagen) for cell adhesion. The nanofibers were uniform, porous, electrically conductive, mechanically strong, and stable under physiological conditions. Surface amination boosted biocompatibility, 3T3 cell adhesion, and spreading, while the neuronal model rat PC12 cell line showed better differentiation on surface-functionalized mats compared to nonfunctionalized mats. When coupled with electrical stimulation (ES), these mats showed comparable or faster neurite formation and elongation than the collagen-coated mats with no-ES conditions. The findings indicate that surface amination in combination with ES may provide an improved strategy to faster nerve regeneration using MEH-PPV-based neural scaffolds.},
}
@article {pmid33448399,
year = {2020},
author = {},
title = {Liana T. Burghardt.},
journal = {The New phytologist},
volume = {228},
number = {1},
pages = {24-25},
doi = {10.1111/nph.16869},
pmid = {33448399},
issn = {1469-8137},
}
@article {pmid33448393,
year = {2020},
author = {Lennon, S and Dolan, L},
title = {The New Phytologist Tansley Medal 2018 - Liana Burghardt and Jana Sperschneider.},
journal = {The New phytologist},
volume = {228},
number = {1},
pages = {5},
doi = {10.1111/nph.16870},
pmid = {33448393},
issn = {1469-8137},
}
@article {pmid33447935,
year = {2021},
author = {Lamin, H and Alami, S and Lamrabet, M and Bouhnik, O and Bennis, M and Abdelmoumen, H and Bedmar, EJ and Missbah-El Idrissi, M},
title = {Bradyrhizobium sp. sv. retamae nodulates Retama monosperma grown in a lead and zinc mine tailings in Eastern Morocco.},
journal = {Brazilian journal of microbiology : [publication of the Brazilian Society for Microbiology]},
volume = {},
number = {},
pages = {},
pmid = {33447935},
issn = {1678-4405},
abstract = {The aim of this work was to characterize and identify some bacteria isolated from the root nodules of Retama monosperma grown in Sidi Boubker lead and zinc mine tailings. Very few root nodules were obtained on the root nodules of R. monosperma grown in these soils. The three bacteria isolated from the root nodules were tolerant in vitro to different concentrations of heavy metals, including lead and zinc. The rep-PCR experiments showed that the three isolates have different molecular fingerprints and were considered as three different strains. The analysis of their 16S rRNA gene sequences proved their affiliation to the genus Bradyrhizobium. The analysis and phylogeny of the housekeeping genes atpD, glnII, gyrB, recA, and rpoB confirmed that the closest species was B. valentinum with similarity percentages of 95.61 to 95.82%. The three isolates recovered from the root nodules were slow-growing rhizobia capable to renodulate their original host plant in the presence of Pb-acetate. They were able to nodulate R. sphaerocarpa and Lupinus luteus also but not Glycine max or Phaseolus vulgaris. The phylogeny of the nodA and nodC nodulation genes as well as the nifH gene of the three strains showed that they belong to the symbiovar retamae of the genus Bradyrhizobium. The three strains isolated could be considered for use as inoculum for Retama plants before use in phytoremediation experiments.},
}
@article {pmid33445955,
year = {2021},
author = {Ravi, S and Jadhav, S and Vaidya, A and Ghooi, R},
title = {Repurposing drugs during the COVID-19 pandemic and beyond.},
journal = {Pharmaceutical patent analyst},
volume = {},
number = {},
pages = {},
doi = {10.4155/ppa-2020-0031},
pmid = {33445955},
issn = {2046-8962},
}
@article {pmid33445801,
year = {2021},
author = {Leppyanen, IV and Pavlova, OA and Vashurina, MA and Bovin, AD and Dolgikh, AV and Shtark, OY and Sendersky, IV and Dolgikh, VV and Tikhonovich, IA and Dolgikh, EA},
title = {LysM Receptor-Like Kinase LYK9 of Pisum Sativum L. May Regulate Plant Responses to Chitooligosaccharides Differing in Structure.},
journal = {International journal of molecular sciences},
volume = {22},
number = {2},
pages = {},
doi = {10.3390/ijms22020711},
pmid = {33445801},
issn = {1422-0067},
support = {No. 16-16-10043 and No. 17-76-30016//Russian Science Foundation/ ; },
abstract = {This study focused on the interactions of pea (Pisum sativum L.) plants with phytopathogenic and beneficial fungi. Here, we examined whether the lysin-motif (LysM) receptor-like kinase PsLYK9 is directly involved in the perception of long- and short-chain chitooligosaccharides (COs) released after hydrolysis of the cell walls of phytopathogenic fungi and identified in arbuscular mycorrhizal (AM) fungal exudates. The identification and analysis of pea mutants impaired in the lyk9 gene confirmed the involvement of PsLYK9 in symbiosis development with AM fungi. Additionally, PsLYK9 regulated the immune response and resistance to phytopathogenic fungi, suggesting its bifunctional role. The existence of co-receptors may provide explanations for the potential dual role of PsLYK9 in the regulation of interactions with pathogenic and AM fungi. Co-immunoprecipitation assay revealed that PsLYK9 and two proposed co-receptors, PsLYR4 and PsLYR3, can form complexes. Analysis of binding capacity showed that PsLYK9 and PsLYR4, synthesized as extracellular domains in insect cells, were able to bind the deacetylated (DA) oligomers CO5-DA-CO8-DA. Our results suggest that the receptor complex consisting of PsLYK9 and PsLYR4 can trigger a signal pathway that stimulates the immune response in peas. However, PsLYR3 seems not to be involved in the perception of CO4-5, as a possible co-receptor of PsLYK9.},
}
@article {pmid33445484,
year = {2021},
author = {Vicente, C and Legaz, ME and Sánchez-Elordi, E},
title = {Physiological Basis of Smut Infectivity in the Early Stages of Sugar Cane Colonization.},
journal = {Journal of fungi (Basel, Switzerland)},
volume = {7},
number = {1},
pages = {},
doi = {10.3390/jof7010044},
pmid = {33445484},
issn = {2309-608X},
abstract = {Sugar cane smut (Sporisorium scitamineum) interactions have been traditionally considered from the plant's point of view: How can resistant sugar cane plants defend themselves against smut disease? Resistant plants induce several defensive mechanisms that oppose fungal attacks. Herein, an overall view of Sporisorium scitamineum's mechanisms of infection and the defense mechanisms of plants are presented. Quorum sensing effects and a continuous reorganization of cytoskeletal components, where actin, myosin, and microtubules are required to work together, seem to be some of the keys to a successful attack.},
}
@article {pmid33326418,
year = {2020},
author = {Umeki, M and Yamashita, H and Suzuki, G and Sato, T and Ohara, S and Koike, K},
title = {Fecal pellets of giant clams as a route for transporting Symbiodiniaceae to corals.},
journal = {PloS one},
volume = {15},
number = {12},
pages = {e0243087},
pmid = {33326418},
issn = {1932-6203},
mesh = {Alveolata/classification/genetics/*isolation & purification ; Animals ; Anthozoa/*parasitology ; Bivalvia/*parasitology ; Coral Reefs ; DNA, Protozoan/genetics ; Feces/parasitology ; Photosynthesis ; Sequence Analysis, DNA ; Symbiosis ; },
abstract = {Because more than 80% of species of gamete-spawning corals, including most Acroporidae species, do not inherit Symbiodiniaceae from their parents, they must acquire symbiont cells from sources in their environment. To determine whether photosynthetically competent Symbiodiniaceae expelled as fecal pellets from giant clams are capable of colonizing corals, we conducted laboratory experiments in which planula larvae of Acropora tenuis were inoculated with the cells in fecal pellets obtained from Tridacna crocea. T. crocea fecal pellets were administered once a day, and three days later, cells of Symbiodiniaceae from the fecal pellets had been taken up by the coral larvae. T. crocea fecal pellets were not supplied from the 4th day until the 8th day, and the cell densities in the larvae increased until the 8th day, which indicated the successful colonization by Symbiodiniaceae. The control group exhibited the highest mean percentage of larvae (100%) that were successfully colonized by culture strains of Symbiodiniaceae, and larvae inoculated with fecal pellets reached a colonization percentage of 66.7 ~ 96.7% on the 8th day. The highest colonization rate was achieved with the fecal pellets containing cells with high photosynthetic competency (Fv/Fm). Interestingly, the genetic composition of Symbiodiniaceae in the larvae retrieved on the 8th day differed from that in the fecal pellets and showed exclusive domination of the genus Symbiodinium. A minor but significant population of the genus Cladocopium in the fecal pellets was not inherited by the larvae. These experiments provided the first demonstration that the Symbiodiniaceae from tridacnine clams provided via fecal pellets can colonize and even proliferate in coral larvae.},
}
@article {pmid32601351,
year = {2020},
author = {Basu, DN and Kunte, K},
title = {Tools of the trade: MicroCT reveals native structure and functional morphology of organs that drive caterpillar-ant interactions.},
journal = {Scientific reports},
volume = {10},
number = {1},
pages = {10593},
pmid = {32601351},
issn = {2045-2322},
mesh = {Animals ; Ants/*physiology ; Biological Evolution ; Butterflies/*physiology ; Larva/*anatomy & histology/physiology ; Lepidoptera/genetics/physiology ; Plant Nectar ; Structure-Activity Relationship ; Symbiosis/physiology ; X-Ray Microtomography/methods ; },
abstract = {Caterpillars of many lycaenid butterflies are tended by ants that offer protection from predators and parasitoids. Specialized structures such as glands, ciliary organs and chitinous ornamentation in caterpillars play key roles in the underlying tactile, acoustic, and chemical communication between caterpillars and ants. Although the ecological, evolutionary, and behavioural aspects of these interactions are well studied, the mechanisms (i.e., the functional morphology) that drive the specialized interactive organs are poorly characterized. We used advanced X-ray microtomography (MicroCT) to delineate internal, native morphology of specialized larval dew patches, nectar glands, and tactile ciliary organs that mediate interactions between Crematogaster ants and caterpillars of the obligate myrmecophilous Apharitis lilacinus butterfly. Our non-destructive MicroCT analysis provided novel 3-D insights into the native structure and positions of these specialized organs in unmatched detail. This analysis also suggested a functional relationship between organ structures and surrounding muscles and nervation that operate the glands and tactile organs, including a 'lasso bag' control mechanism for dew patches and muscle control for other organs. This provided a holistic understanding of the organs that drive very close caterpillar-ant interactions. Our MicroCT analysis opens a door for similar structural and functional analysis of adaptive insect morphology.},
}
@article {pmid31918781,
year = {2020},
author = {Cholewińska, P and Czyż, K and Nowakowski, P and Wyrostek, A},
title = {The microbiome of the digestive system of ruminants - a review.},
journal = {Animal health research reviews},
volume = {21},
number = {1},
pages = {3-14},
doi = {10.1017/S1466252319000069},
pmid = {31918781},
issn = {1475-2654},
mesh = {Animals ; Ecosystem ; *Gastrointestinal Microbiome ; *Rumen/microbiology ; *Ruminants/microbiology ; Symbiosis ; },
abstract = {This review aims to explain the influence and characterization of the microbiome in the ruminant digestive system by presenting the knowledge collected so far. The knowledge presented in this work is focused on the main factors affecting the microbiome and the main dependencies that have been found in it so far. The microbiome in the rumen is the first to come into contact with the biomass of the forage and its main purpose is to decompose into smaller particles or compounds. With the gradual increase in knowledge about the microbiome, there is a chance to manipulate it so that the animal continues to live in a symbiotic relationship with it, while reducing greenhouse gas emissions to the environment as well as increasing feed efficiency. Therefore, understanding the influence of the ruminant microbiome is the main step to achieve such results. However, learning the relationship between microorganisms is only at an early stage, because research focuses mainly on taxonomy. Future research should focus on interactions in the ecosystem which is the microbiome, on explaining individual functions and on influence of environmental factors.},
}
@article {pmid33443511,
year = {2021},
author = {Ozulumba, T and Ingavle, G and Gogotsi, Y and Sandeman, S},
title = {Moderating cellular inflammation using 2-dimensional titanium carbide MXene and graphene variants.},
journal = {Biomaterials science},
volume = {},
number = {},
pages = {},
doi = {10.1039/d0bm01953d},
pmid = {33443511},
issn = {2047-4849},
abstract = {The effective control of microbial and metabolically derived biological toxins which negatively impact physical health remains a key challenge for the 21st century. 2-Dimensional graphene and MXene nanomaterials are relatively new additions to the field of biomedical materials with superior external surface areas suited to adsorptive remediation of biological toxins. However, relatively little is known about their physiological interactions with biological systems and, to date, no comparative biological studies have been done. This study compares titanium carbide MXene (Ti3C2Tx) in multilayered and delaminated forms with graphene variants to assess the impact of variable physical properties on cellular inflammatory response to endotoxin stimulus. No significant impact on cell metabolism or induction of inflammatory pathways leading to cell death was observed. No significant increase in markers of blood cell activation and haemolysis occurred. Whilst graphene nanoplatelets (GNP), graphene oxide (GO) and Ti3C2Tx showed insignificant antibacterial activity towards Escherichia coli, silver nanoparticle-modified GO (GO-Ag) induced bacterial cell death and at a lower dose than silver nanoparticles. All nanomaterials significantly reduced bacterial endotoxin induced THP-1 monocyte IL-8, IL-6 and TNF-α cytokine production by >99%, >99% and >80% respectively, compared to control groups. This study suggests the utility of these nanomaterials as adsorbents in blood contacting medical device applications for removal of inflammatory cytokines linked to poor outcome in patients with life-threatening infection.},
}
@article {pmid33203892,
year = {2020},
author = {Huang, YL and Mayfield, AB and Fan, TY},
title = {Effects of feeding on the physiological performance of the stony coral Pocillopora acuta.},
journal = {Scientific reports},
volume = {10},
number = {1},
pages = {19988},
pmid = {33203892},
issn = {2045-2322},
mesh = {Animals ; Anthozoa/*physiology ; Aquaculture/methods ; Artemia/physiology ; Autotrophic Processes/physiology ; Coral Reefs ; Darkness ; Dinoflagellida/physiology ; Feeding Behavior/*physiology ; Heterotrophic Processes/physiology ; Light ; Photosynthesis/physiology ; Pigmentation/physiology ; Symbiosis/physiology ; },
abstract = {Reef-building corals rely on both heterotrophy and endosymbiotic dinoflagellate autotrophy to meet their metabolic needs. Those looking to culture these organisms for scientific or industrial purposes must therefore consider both feeding regimes and the light environment. Herein the effects of three photosynthetically active radiation (PAR) levels were assessed in fed and unfed specimens of the model coral Pocillopora acuta that were cultured in a recirculating aquaculture system (RAS). Half of the corals were fed Artemia sp. brine shrimp in a separate feeding tank to prevent biofouling, and fragments were exposed to PAR levels of 105, 157, or 250 μmol quanta m-2 s-1 over a 12-h period each day. All cultured corals survived the 140-day treatment, and the physiological response variables assessed-buoyant weight, specific growth rate, linear extension, color, and Fv/Fm-were significantly influenced by feeding, and, to a lesser extent, light. Specifically, fed corals grew faster and larger, and presented darker pigmentation; corals fed at the highest light levels grew at the fastest rate (6 cm year-1 or 175 mg g-1 week-1). Given the high physiological performance observed, we advocate the active feeding of brine shrimp in RAS by those looking to cultivate P. acuta, and likely other corals, over long-term timescales.},
}
@article {pmid33002324,
year = {2021},
author = {Izraeli, Y and Lalzar, M and Netanel, N and Mozes-Daube, N and Steinberg, S and Chiel, E and Zchori-Fein, E},
title = {Wolbachia influence on the fitness of Anagyrus vladimiri (Hymenoptera: Encyrtidae), a bio-control agent of mealybugs.},
journal = {Pest management science},
volume = {77},
number = {2},
pages = {1023-1034},
doi = {10.1002/ps.6117},
pmid = {33002324},
issn = {1526-4998},
support = {20-02-0092//Chief Scientist of Agriculture, Israel/ ; },
mesh = {Animals ; Female ; *Hymenoptera ; Multilocus Sequence Typing ; Reproduction ; Symbiosis ; *Wasps ; *Wolbachia/genetics ; },
abstract = {BACKGROUND: Like numerous other animals, biocontrol agents (BCAs) of arthropod pests carry various microorganisms that may have diverse effects on the biology of their eukaryote hosts. We postulated that it is possible to improve the efficacy of BCAs by manipulating the composition of their associated microbiota. The parasitoid wasp Anagyrus vladimiri (Hymenoptera: Encyrtidae) from a mass-rearing facility was chosen for testing this hypothesis.
RESULTS: High-throughput sequencing analysis indicated that fungal abundance in A. vladimiri was low and variable, whereas the bacterial community was dominated by the endosymbiont Wolbachia. Wolbachia was fixed in the mass-rearing population, whereas in field-collected A. vladimiri Wolbachia's prevalence was only approximately 20%. Identification of Wolbachia strains from the two populations by Multi Locus Sequence Typing, revealed two closely related but unique strains. A series of bioassays with the mass-rearing Wolbachia-fixed (W+) and a derived antibiotic-treated Wolbachia-free (W-) lines revealed that: (i) Wolbachia does not induce reproductive manipulations; (ii) W- females have higher fecundity when reared individually, but not when reared with conspecifics; (iii) W+ females outcompete W- when they share hosts for oviposition; (iv) longevity and developmental time were similar in both lines.
CONCLUSIONS: The findings suggest that W+ A. vladimiri have no clear fitness benefit under mass-rearing conditions and may be disadvantageous under lab-controlled conditions. In a broader view, the results suggest that augmentative biological control can benefit from manipulation of the microbiome of natural enemies.},
}
@article {pmid32096554,
year = {2020},
author = {Preedy, KF and Chaplain, MAJ and Leybourne, DJ and Marion, G and Karley, AJ},
title = {Learning-induced switching costs in a parasitoid can maintain diversity of host aphid phenotypes although biocontrol is destabilized under abiotic stress.},
journal = {The Journal of animal ecology},
volume = {89},
number = {5},
pages = {1216-1229},
doi = {10.1111/1365-2656.13189},
pmid = {32096554},
issn = {1365-2656},
mesh = {Animals ; *Aphids ; Enterobacteriaceae ; Phenotype ; Stress, Physiological ; Symbiosis ; *Wasps ; },
abstract = {Aphid populations frequently include phenotypes that are resistant to parasitism by hymenopterous parasitoid wasps, which is often attributed to the presence of 'protective' facultative endosymbionts residing in aphid tissues, particularly Hamiltonella defensa. In field conditions, under parasitoid pressure, the observed coexistence of aphids with and without protective symbionts cannot be explained by their difference in fitness alone. Using the cereal aphid Rhopalosiphum padi as a model, we propose an alternative mechanism whereby parasitoids are more efficient at finding common phenotypes of aphid and experience a fitness cost when switching to the less common phenotype. We construct a model based on delay differential equations and parameterize and validate the model with values within the ranges obtained from experimental studies. We then use it to explore the possible effects on system dynamics under conditions of environmental stress, using our existing data on the effects of drought stress in crops as an example. We show the 'switching penalty' incurred by parasitoids leads to stable coexistence of aphids with and without H. defensa and provides a potential mechanism for maintaining phenotypic diversity among host organisms. We show that drought-induced reduction in aphid development time has little impact. However, greater reduction in fecundity on droughted plants of symbiont-protected aphids can cause insect population cycles when the system would be stable in the absence of drought stress. The stabilizing effect of the increased efficiency in dealing with more commonly encountered host phenotypes is applicable to a broad range of consumer-resource systems and could explain stable coexistence in competitive environments. The loss of stable coexistence when drought has different effects on the competing aphid phenotypes highlights the importance of scenario testing when considering biocontrol for pest management.},
}
@article {pmid31815300,
year = {2020},
author = {Markova, DN and Christensen, SM and Betrán, E},
title = {Telomere-Specialized Retroelements in Drosophila: Adaptive Symbionts of the Genome, Neutral, or in Conflict?.},
journal = {BioEssays : news and reviews in molecular, cellular and developmental biology},
volume = {42},
number = {1},
pages = {e1900154},
doi = {10.1002/bies.201900154},
pmid = {31815300},
issn = {1521-1878},
mesh = {Animals ; Drosophila/*genetics ; *Genome, Insect ; Long Interspersed Nucleotide Elements ; Retroelements/*genetics ; Symbiosis ; Telomerase/genetics/metabolism ; Telomere/*genetics/metabolism ; },
abstract = {Linear chromosomes shorten in every round of replication. In Drosophila, telomere-specialized long interspersed retrotransposable elements (LINEs) belonging to the jockey clade offset this shortening by forming head-to-tail arrays at Drosophila telomere ends. As such, these telomeric LINEs have been considered adaptive symbionts of the genome, protecting it from premature decay, particularly as Drosophila lacks a conventional telomerase holoenzyme. However, as reviewed here, recent work reveals a high degree of variation and turnover in the telomere-specialized LINE lineages across Drosophila. There appears to be no absolute requirement for LINE activity to maintain telomeres in flies, hence the suggestion that the telomere-specialized LINEs may instead be neutral or in conflict with the host, rather than adaptive.},
}
@article {pmid33436514,
year = {2021},
author = {Fagorzi, C and Bacci, G and Huang, R and Cangioli, L and Checcucci, A and Fini, M and Perrin, E and Natali, C and diCenzo, GC and Mengoni, A},
title = {Nonadditive Transcriptomic Signatures of Genotype-by-Genotype Interactions during the Initiation of Plant-Rhizobium Symbiosis.},
journal = {mSystems},
volume = {6},
number = {1},
pages = {},
pmid = {33436514},
issn = {2379-5077},
abstract = {Rhizobia are ecologically important, facultative plant-symbiotic microbes. In nature, there is a large variability in the association of rhizobial strains and host plants of the same species. Here, we evaluated whether plant and rhizobial genotypes influence the initial transcriptional response of rhizobium following perception of a host plant. RNA sequencing of the model rhizobium Sinorhizobium meliloti exposed to root exudates or luteolin (an inducer of nod genes, involved in the early steps of symbiotic interaction) was performed on a combination of three S. meliloti strains and three alfalfa varieties as host plants. The response to root exudates involved hundreds of changes in the rhizobium transcriptome. Of the differentially expressed genes, 35% were influenced by the strain genotype, 16% were influenced by the plant genotype, and 29% were influenced by strain-by-host plant genotype interactions. We also examined the response of a hybrid S. meliloti strain in which the symbiotic megaplasmid (∼20% of the genome) was mobilized between two of the above-mentioned strains. Dozens of genes were upregulated in the hybrid strain, indicative of nonadditive variation in the transcriptome. In conclusion, this study demonstrated that transcriptional responses of rhizobia upon perception of legumes are influenced by the genotypes of both symbiotic partners and their interaction, suggesting a wide spectrum of genetic determinants involved in the phenotypic variation of plant-rhizobium symbiosis.IMPORTANCE A sustainable way for meeting the need of an increased global food demand should be based on a holobiont perspective, viewing crop plants as intimately associated with their microbiome, which helps improve plant nutrition, tolerance to pests, and adverse climate conditions. However, the genetic repertoire needed for efficient association with plants by the microbial symbionts is still poorly understood. The rhizobia are an exemplary model of facultative plant symbiotic microbes. Here, we evaluated whether genotype-by-genotype interactions could be identified in the initial transcriptional response of rhizobium perception of a host plant. We performed an RNA sequencing study to analyze the transcriptomes of different rhizobial strains elicited by root exudates of three alfalfa varieties as a proxy of an early step of the symbiotic interaction. The results indicated strain- and plant variety-dependent variability in the observed transcriptional changes, providing fundamentally novel insights into the genetic basis of rhizobium-plant interactions. Our results provide genetic insights and perspective to aid in the exploitation of natural rhizobium variation for improvement of legume growth in agricultural ecosystems.},
}
@article {pmid33436431,
year = {2021},
author = {Deehan, M and Lin, W and Blum, B and Emili, A and Frydman, H},
title = {Intracellular Density of Wolbachia Is Mediated by Host Autophagy and the Bacterial Cytoplasmic Incompatibility Gene cifB in a Cell Type-Dependent Manner in Drosophila melanogaster.},
journal = {mBio},
volume = {12},
number = {1},
pages = {},
pmid = {33436431},
issn = {2150-7511},
abstract = {Autophagy is an intracellular degradation pathway involved in innate immunity. Pathogenic bacteria have evolved several mechanisms to escape degradation or exploit autophagy to acquire host nutrients. In the case of endosymbionts, which often have commensal or mutualistic interactions with the host, autophagy is not well characterized. We utilized tissue-specific autophagy mutants to determine if Wolbachia, a vertically transmitted obligate endosymbiont of Drosophila melanogaster, is regulated by autophagy in somatic and germ line cell types. Our analysis revealed core autophagy proteins Atg1 and Atg8 and a selective autophagy-specific protein Ref(2)p negatively regulate Wolbachia in the hub, a male gonad somatic cell type. Furthermore, we determined that the Wolbachia effector protein, CifB, modulates autophagy-Wolbachia interactions, identifying a new host-related pathway which these bacterial proteins interact with. In the female germ line, the cell type necessary for inheritance of Wolbachia through vertical transmission, we discovered that bulk autophagy mediated by Atg1 and Atg8 positively regulates Wolbachia density, whereas Ref(2)p had no effect. Global metabolomics of fly ovaries deficient in germ line autophagy revealed reduced lipid and carbon metabolism, implicating metabolites from these pathways as positive regulators of Wolbachia Our work provides further understanding of how autophagy affects bacteria in a cell type-dependent manner.IMPORTANCE Autophagy is a eukaryotic intracellular degradation pathway which can act as an innate immune response to eliminate pathogens. Conversely, pathogens can evolve proteins which modulate the autophagy pathway to subvert degradation and establish an infection. Wolbachia, a vertically transmitted obligate endosymbiont which infects up to 40% of insect species, is negatively regulated by autophagy in whole animals, but the specific molecular mechanism and tissue which govern this interaction remain unknown. Our studies use cell type-specific autophagy mutants to reveal that Wolbachia is negatively regulated by selective autophagy in the soma, while nonselective autophagy positively regulates Wolbachia in the female germ line. These data provide evidence that cell type can drive different basal autophagy programs which modulate intracellular microbes differently. Additionally, we identified that the Wolbachia effector CifB acts in the selective autophagy pathway to aid in intracellular bacterial survival, providing a new function for CifB beyond its previously identified role in reproductive manipulation.},
}
@article {pmid33435432,
year = {2021},
author = {Wang, R and Luo, S and Clarke, BB and Belanger, FC},
title = {The Epichloëfestucae Antifungal Protein Efe-AfpA Is also a Possible Effector Protein Required for the Interaction of the Fungus with Its Host Grass Festuca rubra subsp. rubra.},
journal = {Microorganisms},
volume = {9},
number = {1},
pages = {},
doi = {10.3390/microorganisms9010140},
pmid = {33435432},
issn = {2076-2607},
support = {2018-11-661//United States Golf Association/ ; 2020//Rutgers Center for Turfgrass Science/ ; },
abstract = {Strong creeping red fescue (Festuca rubra subsp. rubra) is a commercially important low-maintenance turfgrass and is often naturally infected with the fungal endophyte Epichloëfestucae. Epichloë spp. are endophytes of several cool-season grass species, often conferring insect resistance to the grass hosts due to the production of toxic alkaloids. In addition to insect resistance, a unique feature of the strong creeping red fescue/E. festucae symbiosis is the endophyte-mediated disease resistance to the fungal pathogen Clarireedia jacksonii, the causal agent of dollar spot disease. Such disease resistance is not a general feature of other grass/ Epichloë interactions. E. festucae isolates infecting red fescue have an antifungal protein gene Efe-afpA, whereas most other Epichloë spp. do not have a similar gene. The uniqueness of this gene suggests it may, therefore, be a component of the unique disease resistance seen in endophyte-infected red fescue. Here, we report the generation of CRISPR-Cas9 Efe-afpA gene knockouts with the goal of determining if absence of the protein in endophyte-infected Festuca rubra leads to disease susceptibility. However, it was not possible to infect plants with the knockout isolates, although infection was possible with the wild type E. festucae and with complemented isolates. This raises the interesting possibility that, in addition to having antifungal activity, the protein is required for the symbiotic interaction. The antifungal protein is a small secreted protein with high expression in planta relative to its expression in culture, all characteristics consistent with effector proteins. If Efe-AfpA is an effector protein it must be specific to certain interactions, since most Epichloë spp. do not have such a gene in their genomes.},
}
@article {pmid33435396,
year = {2021},
author = {Yang, CY and Chen, TW and Lu, WL and Liang, SS and Huang, HD and Tseng, CP and Tarng, DC},
title = {Synbiotics Alleviate the Gut Indole Load and Dysbiosis in Chronic Kidney Disease.},
journal = {Cells},
volume = {10},
number = {1},
pages = {},
doi = {10.3390/cells10010114},
pmid = {33435396},
issn = {2073-4409},
support = {V106D25-003-MY3, VGHUST107-G5-3-3, and VGHUST109-V5-1-2//Taipei Veterans General Hospital/ ; MOST 105-2628-B-075-008-MY3, MOST 108-2633-B-009-001, MOST 109-2314-B-010-053-MY3, and MOST 109-2321-B-009-007//Ministry of Science and Technology, Taiwan/ ; Yin Yen-Liang Foundation Development and Construction Plan (107F-M01-0504)//National Yang-Ming University School of Medicine/ ; Center for Intelligent Drug Systems and Smart Bio-devices (IDS2B)//Ministry of Education/ ; },
abstract = {Chronic kidney disease (CKD) has long been known to cause significant digestive tract pathology. Of note, indoxyl sulfate is a gut microbe-derived uremic toxin that accumulates in CKD patients. Nevertheless, the relationship between gut microbiota, fecal indole content, and blood indoxyl sulfate level remains unknown. In our study, we established an adenine-induced CKD rat model, which recapitulates human CKD-related gut dysbiosis. Synbiotic treatment in CKD rats showed a significant reduction in both the indole-producing bacterium Clostridium and fecal indole amount. Furthermore, gut microbiota diversity was reduced in CKD rats but was restored after synbiotic treatment. Intriguingly, in our end-stage kidney disease (ESKD) patients, the abundance of indole-producing bacteria, Bacteroides, Prevotella, and Clostridium, is similar to that of healthy controls. Consistently, the fecal indole tends to be higher in the ESKD patients, but the difference did not achieve statistical significance. However, the blood level of indoxyl sulfate was significantly higher than that of healthy controls, implicating that under an equivalent indole production rate, the impaired renal excretion contributes to the accumulation of this notorious uremic toxin. On the other hand, we did identify two short-chain fatty acid-producing bacteria, Faecalibacterium and Roseburia, were reduced in ESKD patients as compared to the healthy controls. This may contribute to gut dysbiosis. We also identified that three genera Fusobacterium, Shewanella, and Erwinia, in the ESKD patients but not in the healthy controls. Building up gut symbiosis to treat CKD is a novel concept, but once proved effective, it will provide an additional treatment strategy for CKD patients.},
}
@article {pmid33435069,
year = {2018},
author = {Borah, R and Ingavle, GC and Sandeman, SR and Kumar, A and Mikhalovsky, SV},
title = {Amine-Functionalized Electrically Conductive Core-Sheath MEH-PPV:PCL Electrospun Nanofibers for Enhanced Cell-Biomaterial Interactions.},
journal = {ACS biomaterials science & engineering},
volume = {4},
number = {9},
pages = {3327-3346},
doi = {10.1021/acsbiomaterials.8b00624},
pmid = {33435069},
issn = {2373-9878},
abstract = {In the present study, a conducting polymer, poly[2-methoxy-5-(2-ethylhexyloxy)-1,4-phenylenevinylene] (MEH-PPV) along with a biodegradable polymer poly(ε-caprolactone) (PCL) was used to prepare an electrically conductive, biocompatible, bioactive, and biodegradable nanofibrous scaffold for possible use in neural tissue engineering applications. Core-sheath electrospun nanofibers of PCL as the core and MEH-PPV as the sheath, were surface-functionalized with (3-aminopropyl) triethoxysilane (APTES) and 1,6-hexanediamine to obtain amine-functionalized surface to facilitate cell-biomaterial interactions with the aim of replacing the costly biomolecules such as collagen, fibronectin, laminin, and arginyl-glycyl-aspartic acid (RGD) peptide for surface modification. Scanning electron microscopy (SEM) and transmission electron microscopy (TEM) confirmed the formation of core-sheath morphology of the electrospun nanofibers, whereas Fourier-transform infrared spectroscopy (FTIR) and X-ray photoelectron spectroscopy (XPS) revealed successful incorporation of amine functionality after surface functionalization. Adhesion, spreading, and proliferation of 3T3 fibroblasts were enhanced on the surface-functionalized electrospun meshes, whereas the neuronal model rat pheochromocytoma 12 (PC12) cells also adhered and differentiated into sympathetic neurons on these meshes. Under a constant electric field of 500 mV for 2 h/day for 3 consecutive days, the PC12 cells displayed remarkable improvement in the neurite formation and outgrowth on the surface-functionalized meshes that was comparable to those on the collagen-coated meshes under no electrical signal. Electrical stimulation studies further demonstrated that electrically stimulated PC12 cells cultured on collagen I coated meshes yielded more and longer neurites than those of the unstimulated cells on the same scaffolds. The enhanced neurite growth and differentiation suggest the potential use of these scaffolds for neural tissue engineering applications.},
}
@article {pmid33398001,
year = {2021},
author = {Gray, DA and White, JBR and Oluwole, AO and Rath, P and Glenwright, AJ and Mazur, A and Zahn, M and Baslé, A and Morland, C and Evans, SL and Cartmell, A and Robinson, CV and Hiller, S and Ranson, NA and Bolam, DN and van den Berg, B},
title = {Insights into SusCD-mediated glycan import by a prominent gut symbiont.},
journal = {Nature communications},
volume = {12},
number = {1},
pages = {44},
pmid = {33398001},
issn = {2041-1723},
support = {BB/P003192/1/BB_/Biotechnology and Biological Sciences Research Council/United Kingdom ; 215064/Z/18/Z/WT_/Wellcome Trust/United Kingdom ; 108466/Z/15/Z/WT_/Wellcome Trust/United Kingdom ; MR/N020413/1/MRC_/Medical Research Council/United Kingdom ; },
mesh = {Bacterial Proteins/chemistry/*metabolism ; Cryoelectron Microscopy ; *Gastrointestinal Microbiome ; Ligands ; Magnetic Resonance Spectroscopy ; Models, Molecular ; Oligosaccharides/chemistry ; Polysaccharides/chemistry/*metabolism ; Protein Conformation ; Structure-Activity Relationship ; *Symbiosis ; },
abstract = {In Bacteroidetes, one of the dominant phyla of the mammalian gut, active uptake of large nutrients across the outer membrane is mediated by SusCD protein complexes via a "pedal bin" transport mechanism. However, many features of SusCD function in glycan uptake remain unclear, including ligand binding, the role of the SusD lid and the size limit for substrate transport. Here we characterise the β2,6 fructo-oligosaccharide (FOS) importing SusCD from Bacteroides thetaiotaomicron (Bt1762-Bt1763) to shed light on SusCD function. Co-crystal structures reveal residues involved in glycan recognition and suggest that the large binding cavity can accommodate several substrate molecules, each up to ~2.5 kDa in size, a finding supported by native mass spectrometry and isothermal titration calorimetry. Mutational studies in vivo provide functional insights into the key structural features of the SusCD apparatus and cryo-EM of the intact dimeric SusCD complex reveals several distinct states of the transporter, directly visualising the dynamics of the pedal bin transport mechanism.},
}
@article {pmid33272602,
year = {2021},
author = {Yan, Y and Wang, X and Askari, A and Lee, HS},
title = {A modelling study of the spatially heterogeneous mutualism between electroactive biofilm and planktonic bacteria.},
journal = {The Science of the total environment},
volume = {759},
number = {},
pages = {143537},
doi = {10.1016/j.scitotenv.2020.143537},
pmid = {33272602},
issn = {1879-1026},
mesh = {Bacteria ; Biofilms ; Electrodes ; *Plankton ; *Symbiosis ; },
abstract = {Microbial cooperation widely exists in anaerobic reactors degrading complex pollutants, conventionally studied separately inside the biofilm or the planktonic community. Recent experiments discovered the mutualism between the planktonic bacteria and electroactive biofilm treating propionate, an end-product usually accumulated in anaerobic digesters. Here, a one-dimensional multispecies model found the preference on acetate-based pathway over the hydrogen-based in such community, evidenced by the fact that acetate-originated current takes 66% of the total value and acetate-consuming anode-respiring bacteria takes over 80% of the biofilm. Acetate-based anodic respiration most apparently influences biofilm function while propionate fermentation is the dominant planktonic bio-reaction. Additionally, initial planktonic propionate level shows the ability of coordinating the balance between these two extracellular electron transfer pathways. Increasing the propionate concentration from 2 to 50 mM would increase the steady hydrogen-originated current by 210% but decrease the acetate-originated by 26%, suggesting a vital influence of the planktonic microbial process to the metabolic balance in biofilm. Best strategy to promote the biofilm activity is to increase the biomass density and biofilm conductivity simultaneously, which would increase the current density by 875% without thickening the biofilm thickness or prolonging the growth apparently.},
}
@article {pmid33082320,
year = {2020},
author = {Rayko, M and Komissarov, A and Kwan, JC and Lim-Fong, G and Rhodes, AC and Kliver, S and Kuchur, P and O'Brien, SJ and Lopez, JV},
title = {Draft genome of Bugula neritina, a colonial animal packing powerful symbionts and potential medicines.},
journal = {Scientific data},
volume = {7},
number = {1},
pages = {356},
pmid = {33082320},
issn = {2052-4463},
support = {PURE 51555639//Saint Petersburg State University (St. Petersburg State University)/International ; 17-00-00144//Russian Foundation for Basic Research (RFBR)/International ; 17-00-00144//Russian Foundation for Basic Research (RFBR)/International ; },
mesh = {Animals ; Bryostatins ; Bryozoa/*genetics ; *Genome ; Phylogeny ; Symbiosis ; },
abstract = {Many animal phyla have no representatives within the catalog of whole metazoan genome sequences. This dataset fills in one gap in the genome knowledge of animal phyla with a draft genome of Bugula neritina (phylum Bryozoa). Interest in this species spans ecology and biomedical sciences because B. neritina is the natural source of bioactive compounds called bryostatins. Here we present a draft assembly of the B. neritina genome obtained from PacBio and Illumina HiSeq data, as well as genes and proteins predicted de novo and verified using transcriptome data, along with the functional annotation. These sequences will permit a better understanding of host-symbiont interactions at the genomic level, and also contribute additional phylogenomic markers to evaluate Lophophorate or Lophotrochozoa phylogenetic relationships. The effort also fits well with plans to ultimately sequence all orders of the Metazoa.},
}
@article {pmid32961433,
year = {2020},
author = {Mechri, B and Tekaya, M and Attia, F and Hammami, M and Chehab, H},
title = {Drought stress improved the capacity of Rhizophagus irregularis for inducing the accumulation of oleuropein and mannitol in olive (Olea europaea) roots.},
journal = {Plant physiology and biochemistry : PPB},
volume = {156},
number = {},
pages = {178-191},
doi = {10.1016/j.plaphy.2020.09.011},
pmid = {32961433},
issn = {1873-2690},
mesh = {*Droughts ; Fungi/*physiology ; Iridoids/*metabolism ; Mannitol/*metabolism ; Mycorrhizae/physiology ; Olea/*metabolism/microbiology ; Plant Roots/*metabolism ; Stress, Physiological ; Symbiosis ; },
abstract = {Olive trees are often subjected to a prolonged dry season with low water availability, which induces oxidative stress. Arbuscular mycorrhizal (AM) symbioses can improve olive plant tolerance to water deficit. This study investigated several aspects related to drought tolerance in AM fungi olive plants. Non-AM and AM plants were grown under well-watered or drought-stressed conditions, and mycorrhizal growth response, neutral lipid fatty acid (NLFA)16:1ω5 and phospholipid fatty acid (PLFA) 16:1ω5 in roots (intraradical mycelium) and in soil (extraradical mycelium), carbohydrates (monosaccharides, disaccharides and polyols) and phenolic compounds (phenolic alcohols, flavonoids, lignans, secoiridoids and hydroxycinnamic acid derivatives) were determined. Results showed that the amounts of PLFA 16:1ω5 and NLFA 16:1ω5 were significantly influenced by drought stress conditions. The NLFA 16:1ω5/PLFA 16:1ω5 ratio showed a dramatic decrease (-62%) with the application of water deficit stress, indicating that AM fungi allocated low carbon to storage structures under stress conditions. Mannitol and verbascoside are the main compounds detected in the roots of well-watered plants, whereas oleuropein and mannitol are the main compounds differentially accumulated in the roots of water-stressed plants. The oleuropein/verbascoside ratio increased in the case of drought-stressed AM plants by 30%, while the mannitol/oleuropein ratio was decreased by 46%, when compared to the non-AM stressed plants. Mycorrhization therefore oriented the flux toward the biosynthetic pathway of oleuropein and the data suggest that sugar and phenolic compound metabolism may have been redirected to the formation of oleuropein in roots of AM stressed plants, that may underlie their enhanced tolerance to drought stress.},
}
@article {pmid32836177,
year = {2020},
author = {Grenier, T and Leulier, F},
title = {How commensal microbes shape the physiology of Drosophila melanogaster.},
journal = {Current opinion in insect science},
volume = {41},
number = {},
pages = {92-99},
doi = {10.1016/j.cois.2020.08.002},
pmid = {32836177},
issn = {2214-5753},
mesh = {Animals ; Drosophila melanogaster/growth & development/*microbiology/*physiology ; Gastrointestinal Microbiome ; Host Microbial Interactions ; Longevity ; *Symbiosis ; },
abstract = {The interactions between animals and their commensal microbes profoundly influence the host's physiology. In the last decade, Drosophila melanogaster has been extensively used as a model to study host-commensal microbes interactions. Here, we review the most recent advances in this field. We focus on studies that extend our understanding of the molecular mechanisms underlying the effects of commensal microbes on Drosophila's development and lifespan. We emphasize how commensal microbes influence nutrition and the intestinal epithelium homeostasis; how they elicit immune tolerance mechanisms and how these physiological processes are interconnected. Finally, we discuss the importance of diets and microbial strains and show how they can be confounding factors of microbe mediated host phenotypes.},
}
@article {pmid32823202,
year = {2020},
author = {Scharf, ME},
title = {Challenges and physiological implications of wood feeding in termites.},
journal = {Current opinion in insect science},
volume = {41},
number = {},
pages = {79-85},
doi = {10.1016/j.cois.2020.07.007},
pmid = {32823202},
issn = {2214-5753},
mesh = {Animals ; Gastrointestinal Microbiome/physiology ; Gastrointestinal Tract/physiology ; Isoptera/metabolism/*microbiology/*physiology ; Lignin/metabolism ; Symbiosis ; Wood/*chemistry/metabolism ; },
abstract = {Termites are fascinating insects for a number of reasons, one of which being their specialization on diets of wood lignocellulose. The goal of this review is to consider stress-inducing characteristics of wood and apparent molecular-physiological adaptations in termite guts to overcome these stressors. Defensive factors present in wood include extractive secondary plant metabolites, lignin and related phenolics, crystalline cellulose, and low nitrogen content. Molecular-physiological adaptations of the termite gut to deal with these factors include robust detoxification and antioxidant machinery, the production of a peritrophic matrix and a wide range of cellulases from host and symbiotic sources, and creation of niches available to nitrogen-fixing bacterial symbionts. Considering termite gut physiology and symbioses in the context of stress-response has applied implications. These outcomes can include development of efficient biomass breakdown strategies, protection of microbes during industrial processing applications, and safeguarding wooden structures from termite damage.},
}
@article {pmid32599512,
year = {2020},
author = {Ferreira, AG and Fairlie, S and Moreira, LA},
title = {Insect vectors endosymbionts as solutions against diseases.},
journal = {Current opinion in insect science},
volume = {40},
number = {},
pages = {56-61},
doi = {10.1016/j.cois.2020.05.014},
pmid = {32599512},
issn = {2214-5753},
mesh = {Animals ; Communicable Disease Control/*methods ; Disease Transmission, Infectious/*prevention & control ; Humans ; Insect Vectors/*physiology ; Insecta/*physiology ; *Symbiosis ; Wolbachia/*physiology ; },
abstract = {Viral diseases transmitted by mosquitoes, known as arboviruses, pose a significant threat to human life and are a major burden on many health systems around the world. Currently, arbovirus control strategies rely on insecticides or vector source reduction and, in the absence of effective, accessible and affordable vaccines, mainly on symptomatic based, non-specific treatments. However, insecticides have the potential to interfere with non-target organisms, cause environmental toxicity and insecticide resistance reduces their effectiveness as a sustainable control method. Complementary and sustainable strategies are urgently needed. Wolbachia, an invertebrate endosymbiont, has been used as an alternative strategy for arboviral control, through suppression or modification of mosquito populations. Here we discuss the burden that arboviruses impose on human populations and how Wolbachia can be used as a sustainable strategy for control, in alignment with the United Nations- 2030 Agenda for Sustainable Development.},
}
@article {pmid32485039,
year = {2020},
author = {Belan, HC and Barônio, GJ and Kuster, VC and Oliveira, DC and Vasconcelos, HL},
title = {Extranuptial nectaries in flowers: ants increase the reproductive success of the ant-plant Miconia tococa (Melastomataceae).},
journal = {Plant biology (Stuttgart, Germany)},
volume = {22},
number = {5},
pages = {917-923},
doi = {10.1111/plb.13138},
pmid = {32485039},
issn = {1438-8677},
support = {001//Coordenação de Aperfeiçoamento de Pessoal de Nível Superior/ ; 88887.137914/2017-00//Coordenação de Aperfeiçoamento de Pessoal de Nível Superior/ ; 88887.352134/2019-00//Coordenação de Aperfeiçoamento de Pessoal de Nível Superior/ ; 302588/2015-9//Conselho Nacional de Desenvolvimento Científico e Tecnológico/ ; 441225/2016-0//Conselho Nacional de Desenvolvimento Científico e Tecnológico/ ; },
mesh = {Animals ; *Ants ; *Flowers/anatomy & histology ; *Melastomataceae/anatomy & histology/physiology ; *Plant Nectar ; Pollination ; *Symbiosis ; },
abstract = {Although the production of extranuptial nectar is a common strategy of indirect defence against herbivores among tropical plants, the presence of extranuptial nectaries in reproductive structures is rare, especially in ant-plants. This is because the presence of ants in reproductive organs can generate conflicts between the partners, as ants can inhibit the activity of pollinators or even castrate their host plants. Here we evaluate the hypothesis that the ant-plant Miconia tococa produces nectar in its petals which attracts ants and affects fruit set. Floral buds were analysed using anatomical and histochemical techniques. The frequency and behaviour of floral visitors were recorded in field observations. Finally, an ant exclusion experiment was conducted to evaluate the effect of ant presence on fruit production. The petals of M. tococa have a secretory epidermis that produces sugary compounds. Nectar production occurred during the floral bud stage and attracted 17 species of non-obligate ants (i.e. have a facultative association with ant-plants). Ants foraged only on floral buds, and thus did not affect the activity of pollinators in the neighbouring open flowers. The presence of ants in the inflorescences increased fruit production by 15%. To our knowledge, the production of extranuptial nectar in the reproductive structures of a myrmecophyte is very rare, with few records in the literature. Although studies show conflicts between the partners in the ant-plant interaction, ants that forage on M. tococa floral buds protect the plant against floral herbivores without affecting bee pollination.},
}
@article {pmid32238763,
year = {2020},
author = {Zhang, Y and Bi, Y and Shen, H and Zhang, L},
title = {Arbuscular Mycorrhizal Fungi Enhance Sea Buckthorn Growth in Coal Mining Subsidence Areas in Northwest China.},
journal = {Journal of microbiology and biotechnology},
volume = {30},
number = {6},
pages = {848-855},
doi = {10.4014/jmb.1907.07007},
pmid = {32238763},
issn = {1738-8872},
mesh = {China ; Coal Mining ; *Hippophae/microbiology/physiology ; Mycorrhizae/*physiology ; *Rhizosphere ; Soil Microbiology ; Symbiosis/*physiology ; },
abstract = {Land subsidence induced by underground coal mining leads to severe ecological and environmental problems. Arbuscular mycorrhizal fungi (AMF) have the potential to improve plant growth and soil properties. We aimed to assess the effects of AMF on the growth and soil properties of sea buckthorn under field conditions at different reclamation times. Inoculation with AMF significantly promoted the survival rate of sea buckthorn over a 50-month period, while also increasing plant height after 14, 26, and 50 months. Crown width after 14 months and ground diameter after 50 months of inoculation treatment were significantly higher than in the uninoculated treatment. AMF inoculation significantly improved plant mycorrhizal colonization rate and promoted an increase in mycelial density in the rhizosphere soil. The pH and electrical conductivity of rhizosphere soil also increased after inoculation. Moreover, after 26 and 50 months the soil organic matter in the inoculation treatment was significantly higher than in the control. The number of inoculated soil rhizosphere microorganisms, as well as acid phosphatase activity, also increased. AMF inoculation may play an active role in promoting plant growth and improving soil quality in the long term and is conducive to the rapid ecological restoration of damaged mining areas.},
}
@article {pmid33434644,
year = {2021},
author = {Recorbet, G and Calabrese, S and Balliau, T and Zivy, M and Wipf, D and Boller, T and Courty, PE},
title = {Proteome adaptations under contrasting soil phosphate regimes of Rhizophagus irregularis engaged in a common mycorrhizal network.},
journal = {Fungal genetics and biology : FG & B},
volume = {},
number = {},
pages = {103517},
doi = {10.1016/j.fgb.2021.103517},
pmid = {33434644},
issn = {1096-0937},
abstract = {For many plants, their symbiosis with arbuscular mycorrhizal fungi plays a key role in the acquisition of mineral nutrients such as inorganic phosphate (Pi), in exchange for assimilated carbon. To study gene regulation and function in the symbiotic partners, we and others have used compartmented microcosms in which the extra-radical mycelium (ERM), responsible for mineral nutrient supply for the plants, was separated by fine nylon nets from the associated host roots and could be harvested and analysed in isolation. Here, we used such a model system to perform a quantitative comparative protein profiling of the ERM of Rhizophagus irregularis BEG75, forming a common mycorrhizal network (CMN) between poplar and sorghum roots under a long-term high- or low-Pi fertilization regime. Proteins were extracted from the ERM and analysed by liquid chromatography-tandem mass spectrometry. This workflow identified a total of 1301 proteins, among which 162 displayed a differential amount during Pi limitation, as monitored by spectral counting. Higher abundances were recorded for proteins involved in the mobilization of external Pi, such as secreted acid phosphatase, 3',5'-bisphosphate nucleotidase, and calcium-dependent phosphotriesterase. This was also the case for intracellular phospholipase and lysophospholipases that are involved in the initial degradation of phospholipids from membrane lipids to mobilize internal Pi. In Pi-deficient conditions. The CMN proteome was especially enriched in proteins assigned to beta-oxidation, glyoxylate shunt and gluconeogenesis, indicating that storage lipids rather than carbohydrates are fuelled in ERM as the carbon source to support hyphal growth and energy requirements. The contrasting pattern of expression of AM-specific fatty acid biosynthetic genes between the two plants suggests that in low Pi conditions, fatty acid provision to the fungal network is mediated by sorghum roots but not by poplar. Loss of enzymes involved in arginine synthesis coupled to the mobilization of proteins involved in the breakdown of nitrogen sources such as intercellular purines and amino acids, support the view that ammonium acquisition by host plants through the mycorrhizal pathway may be reduced under low-Pi conditions. This proteomic study highlights the functioning of a CMN in Pi limiting conditions, and provides new perspectives to study plant nutrient acquisition as mediated by arbuscular mycorrhizal fungi.},
}
@article {pmid33432136,
year = {2021},
author = {Ren, FR and Sun, X and Wang, TY and Yan, JY and Yao, YL and Li, CQ and Luan, JB},
title = {Pantothenate mediates the coordination of whitefly and symbiont fitness.},
journal = {The ISME journal},
volume = {},
number = {},
pages = {},
pmid = {33432136},
issn = {1751-7370},
support = {31871967//National Natural Science Foundation of China (National Science Foundation of China)/ ; },
abstract = {Intracellular symbionts in insects often have reduced genomes. Host acquisition of genes from bacteria is an important adaptation that supports symbionts. However, the function of horizontally transferred genes in insect symbiosis remains largely unclear. The primary symbiont Portiera housed in bacteriocytes lacks pantothenate synthesis genes: panB and panC, which is presumably complemented by a fused gene panB-panC (hereafter panBC) horizontally transferred from bacteria in Bemisia tabaci MEAM1. We found panBC in many laboratory cultures, and species of B. tabaci shares a common evolutionary origin. We demonstrated that complementation with whitefly panBC rescued E. coli pantothenate gene knockout mutants. Portiera elimination decreased the pantothenate level and PanBC abundance in bacteriocytes, and reduced whitefly survival and fecundity. Silencing PanBC decreased the Portiera titer, reduced the pantothenate level, and decreased whitefly survival and fecundity. Supplementation with pantothenate restored the symbiont titer, PanBC level, and fitness of RNAi whiteflies. These data suggest that pantothenate synthesis requires cooperation and coordination of whitefly PanBC expression and Portiera. This host-symbiont co-regulation was mediated by the pantothenate level. Our findings demonstrated that pantothenate production, by the cooperation of a horizontally acquired, fused bacteria gene and Portiera, facilitates the coordination of whitefly and symbiont fitness. Thus, this study extends our understanding on the basis of complex host-symbiont interactions.},
}
@article {pmid33431987,
year = {2021},
author = {Strassert, JFH and Wurzbacher, C and Hervé, V and Antany, T and Brune, A and Radek, R},
title = {Long rDNA amplicon sequencing of insect-infecting nephridiophagids reveals their affiliation to the Chytridiomycota and a potential to switch between hosts.},
journal = {Scientific reports},
volume = {11},
number = {1},
pages = {396},
pmid = {33431987},
issn = {2045-2322},
abstract = {Nephridiophagids are unicellular eukaryotes that parasitize the Malpighian tubules of numerous insects. Their life cycle comprises multinucleate vegetative plasmodia that divide into oligonucleate and uninucleate cells, and sporogonial plasmodia that form uninucleate spores. Nephridiophagids are poor in morphological characteristics, and although they have been tentatively identified as early-branching fungi based on the SSU rRNA gene sequences of three species, their exact position within the fungal tree of live remained unclear. In this study, we describe two new species of nephridiophagids (Nephridiophaga postici and Nephridiophaga javanicae) from cockroaches. Using long-read sequencing of the nearly complete rDNA operon of numerous further species obtained from cockroaches and earwigs to improve the resolution of the phylogenetic analysis, we found a robust affiliation of nephridiophagids with the Chytridiomycota-a group of zoosporic fungi that comprises parasites of diverse host taxa, such as microphytes, plants, and amphibians. The presence of the same nephridiophagid species in two only distantly related cockroaches indicates that their host specificity is not as strict as generally assumed.},
}
@article {pmid33430332,
year = {2021},
author = {Goyal, RK and Schmidt, MA and Hynes, MF},
title = {Molecular Biology in the Improvement of Biological Nitrogen Fixation by Rhizobia and Extending the Scope to Cereals.},
journal = {Microorganisms},
volume = {9},
number = {1},
pages = {},
doi = {10.3390/microorganisms9010125},
pmid = {33430332},
issn = {2076-2607},
abstract = {The contribution of biological nitrogen fixation to the total N requirement of food and feed crops diminished in importance with the advent of synthetic N fertilizers, which fueled the "green revolution". Despite being environmentally unfriendly, the synthetic versions gained prominence primarily due to their low cost, and the fact that most important staple crops never evolved symbiotic associations with bacteria. In the recent past, advances in our knowledge of symbiosis and nitrogen fixation and the development and application of recombinant DNA technology have created opportunities that could help increase the share of symbiotically-driven nitrogen in global consumption. With the availability of molecular biology tools, rapid improvements in symbiotic characteristics of rhizobial strains became possible. Further, the technology allowed probing the possibility of establishing a symbiotic dialogue between rhizobia and cereals. Because the evolutionary process did not forge a symbiotic relationship with the latter, the potential of molecular manipulations has been tested to incorporate a functional mechanism of nitrogen reduction independent of microbes. In this review, we discuss various strategies applied to improve rhizobial strains for higher nitrogen fixation efficiency, more competitiveness and enhanced fitness under unfavorable environments. The challenges and progress made towards nitrogen self-sufficiency of cereals are also reviewed. An approach to integrate the genetically modified elite rhizobia strains in crop production systems is highlighted.},
}
@article {pmid33248756,
year = {2021},
author = {Keshavmurthy, S and Beals, M and Hsieh, HJ and Choi, KS and Chen, CA},
title = {Physiological plasticity of corals to temperature stress in marginal coral communities.},
journal = {The Science of the total environment},
volume = {758},
number = {},
pages = {143628},
doi = {10.1016/j.scitotenv.2020.143628},
pmid = {33248756},
issn = {1879-1026},
mesh = {Animals ; *Anthozoa ; Coral Reefs ; Hot Temperature ; Islands ; Republic of Korea ; Stress, Physiological ; Symbiosis ; Taiwan ; Temperature ; },
abstract = {Adaptation and/or acclimatization through various mechanisms have been suggested to help some tropical coral species to overcome temperature-induced bleaching that is intensifying with climate change; however, while much research has been done on the physiological responses of tropical and subtropical corals to stress, little is known about these responses in corals in marginal environments-e.g., high-latitude and non-reefal communities. In this study, we examined the thermal-tolerant physiology of the flowerpot coral, Alveopora japonica, endemic to the high-latitude Jeju Island (33.39°N), South Korea and Oulastrea crispata and Coelastrea aspera from the subtropical non-reefal coral community on the Penghu Islands (23.34°N), Taiwan. Analysis of physiological parameters; photochemical efficiency, Chlorophyll pigment, Symbiodiniaceae cell number and host soluble proteins - showed that A. japonica can survive through a wide range of temperature stresses (10-32 °C) over a period of 8 days without showing signs of bleaching. In addition, corals O. crispata and C. aspera withstood temperature stresses of up to 33 °C and repeated temperature fluctuations without bleaching. Our results indicate that, under large seasonal variations and asymmetrical daily fluctuations in temperature, corals currently living in marginal environments could have thermal plasticity, allowing them to survive in the future climate change scenarios. This study reiterates the importance of studying the eco-physiology of corals that are generally ignored because of their neutral or positive responses to stress.},
}
@article {pmid32229436,
year = {2020},
author = {Zheng, JS and Wahlqvist, ML},
title = {Regulobiosis: A regulatory and food system-sensitive role for fungal symbionts in human evolution and ecobiology.},
journal = {Asia Pacific journal of clinical nutrition},
volume = {29},
number = {1},
pages = {9-15},
doi = {10.6133/apjcn.202003_29(1).0002},
pmid = {32229436},
issn = {1440-6047},
mesh = {Diet ; Fungi/*physiology ; *Host Microbial Interactions ; Humans ; *Microbial Interactions ; Microbiota/*physiology ; Mycobiome/*physiology ; *Symbiosis ; },
abstract = {The role of microbiomes in human biology and health are being extensively investigated, yet how the fungal community or mycobiome contributes to an integral microbiome is unclear and probably underestimated. We review the roles of fungi from the perspectives of their functionality in human biology, their cross-kingdom talk with other human microbial organisms, their dependence on diet and their involvement in human health and diseases. We hypothesize that members of the fungal community may interact as necessary symbionts with members of other human microbiome communities, and play a key role in human biology, yet to be fully understood. We propose further that "regulobiosis", whereby fungi play a regulatory role in human ecobiology, is operative in humans as probably obtains in other forms of life. Fungally-dependent regulobiosis would characterise, at first, microbiomes which include, but are not limited to, bacteria, archaea, and viruses; then, their human host; and, next, provide ecological connectedness.},
}
@article {pmid33429236,
year = {2020},
author = {Torres-Franco, AF and Zuluaga, M and Hernández-Roldán, D and Leroy-Freitas, D and Sepúlveda-Muñoz, CA and Blanco, S and Mota, CR and Muñoz, R},
title = {Assessment of the performance of an anoxic-aerobic microalgal-bacterial system treating digestate.},
journal = {Chemosphere},
volume = {270},
number = {},
pages = {129437},
doi = {10.1016/j.chemosphere.2020.129437},
pmid = {33429236},
issn = {1879-1298},
abstract = {The performance of an anoxic-aerobic microalgal-bacterial system treating synthetic food waste digestate at 10 days of hydraulic retention time via nitrification-denitrification under increasing digestate concentrations of 25%, 50%, and 100% (v/v) was assessed during Stages I, II and III, respectively. The system supported adequate treatment without external CO2 supplementation since sufficient inorganic carbon in the digestate was available for autotrophic growth. High steady-state Total Organic Carbon (TOC) and Total Nitrogen (TN) removal efficiencies of 85-96% and 73-84% were achieved in Stages I and II. Similarly, PO43--P removals of 81 ± 15% and 58 ± 4% were recorded during these stages. During Stage III, the average influent concentrations of 815 ± 35 mg TOC·L-1, 610 ± 23 mg TN·L-1, and 46 ± 11 mg PO43--P·L-1 induced O2 limiting conditions, resulting in TOC, TN and PO43--P removals of 85 ± 3%, 73 ± 3%, and 28 ± 16%, respectively. Digestate concentrations of 25% and 50% favored nitrification-denitrification mechanisms, whereas the treatment of undiluted digestate resulted in higher ammonia volatilization and hampered nitrification-denitrification. In Stages I and II, the microalgal community was dominated by Chlorella vulgaris and Cryptomonas sp., whereas Pseudoanabaena sp. was more abundant during Stage III. Illumina sequencing revealed the presence of carbon and nitrogen transforming bacteria, with dominances of the genera Gemmata, Azospirillum, and Psychrobacter during Stage I, II, and III, respectively. Finally, the high settleability of the biomass (98% of suspended solids removal in the settler) and average C (42%), N (7%), P (0.2%), and S (0.4%) contents recovered in the biomass confirmed its potential for agricultural applications, contributing to a closed-cycle management of food waste.},
}
@article {pmid33428287,
year = {2021},
author = {Corbin, C and Jones, JE and Chrostek, E and Fenton, A and Hurst, GDD},
title = {Thermal sensitivity of the Spiroplasma-Drosophila hydei protective symbiosis: The best of climes, the worst of climes.},
journal = {Molecular ecology},
volume = {},
number = {},
pages = {},
doi = {10.1111/mec.15799},
pmid = {33428287},
issn = {1365-294X},
abstract = {The outcome of natural enemy attack in insects is commonly influenced by the presence of protective symbionts in the host. The degree to which protection functions in natural populations, however, will depend on the robustness of the phenotype and symbiosis to variation in the abiotic environment. We studied the impact of a key environmental parameter - temperature - on the efficacy of the protective effect of the symbiont Spiroplasma on its host Drosophila hydei, against attack by the parasitoid wasp Leptopilina heterotoma. In addition, we investigated the thermal sensitivity of the symbiont's vertical transmission, which may be a key determinant of the ability of the symbiont to persist. We found that vertical transmission was more robust than previously considered, with Spiroplasma being maintained at 25°C, 18°C and with 18/15°C diurnal cycles, with rates of segregational loss only increasing at 15°C. Protection against wasp attack was ablated before symbiont transmission was lost, with the symbiont failing to rescue the fly host at 18°C. We conclude that the presence of a protective symbiosis in natural populations cannot be simply inferred from presence of a symbiont whose protective capacity has been tested under narrow controlled conditions. More broadly, we argue that the thermal environment is likely to represent an important determinant of the evolutionary ecology of defensive symbioses in natural environments, potentially driving seasonal, latitudinal and altitudinal variation in symbiont frequency.},
}
@article {pmid33424822,
year = {2020},
author = {Goldstein, SL and Klassen, JL},
title = {Pseudonocardia Symbionts of Fungus-Growing Ants and the Evolution of Defensive Secondary Metabolism.},
journal = {Frontiers in microbiology},
volume = {11},
number = {},
pages = {621041},
doi = {10.3389/fmicb.2020.621041},
pmid = {33424822},
issn = {1664-302X},
abstract = {Actinobacteria belonging to the genus Pseudonocardia have evolved a close relationship with multiple species of fungus-growing ants, where these bacteria produce diverse secondary metabolites that protect the ants and their fungal mutualists from disease. Recent research has charted the phylogenetic diversity of this symbiosis, revealing multiple instances where the ants and Pseudonocardia have formed stable relationships in which these bacteria are housed on specific regions of the ant's cuticle. Parallel chemical and genomic analyses have also revealed that symbiotic Pseudonocardia produce diverse secondary metabolites with antifungal and antibacterial bioactivities, and highlighted the importance of plasmid recombination and horizontal gene transfer for maintaining these symbiotic traits. Here, we propose a multi-level model for the evolution of Pseudonocardia and their secondary metabolites that includes symbiont transmission within and between ant colonies, and the potentially independent movement and diversification of their secondary metabolite biosynthetic genes. Because of their well-studied ecology and experimental tractability, Pseudonocardia symbionts of fungus-growing ants are an especially useful model system to understand the evolution of secondary metabolites, and also comprise a significant source of novel antibiotic and antifungal agents.},
}
@article {pmid33424816,
year = {2020},
author = {Miyabayashi, H and Jain, R and Suzuki, S and Grogan, DW and Kurosawa, N},
title = {PolB1 Is Sufficient for DNA Replication and Repair Under Normal Growth Conditions in the Extremely Thermophilic Crenarchaeon Sulfolobus acidocaldarius.},
journal = {Frontiers in microbiology},
volume = {11},
number = {},
pages = {613375},
doi = {10.3389/fmicb.2020.613375},
pmid = {33424816},
issn = {1664-302X},
abstract = {The thermophilic crenarchaeon Sulfolobus acidocaldarius has four DNA polymerases (DNAPs): PolB1, PolB2, PolB3, and Dbh (PolY). Previous in vitro studies suggested that PolB1 is the main replicative DNAP of Sulfolobales whereas PolB2 and Y-family polymerases Dpo4 (Saccharolobus solfataricus) or Dbh are involved in DNA repair and translesion DNA synthesis. On the other hand, there are various opinions about the role of PolB3, which remains to be clearly resolved. In order to examine the roles of the DNAPs of S. acidocaldarius through in vivo experiments, we constructed polB2, polB3, and dbh deletion strains and characterized their phenotypes. Efforts to construct a polB1 deletion strain were not successful; in contrast, it was possible to isolate triple gene-deletion strains lacking polB2, polB3, and dbh. The growth of these strains was nearly the same as that of the parent strains under normal growth conditions. The polB2, polB3, and dbh single-deletion strains were sensitive to some types of DNA-damaging treatments, but exhibited normal sensitivity to UV irradiation and several other damaging treatments. Overall, the genotype which exhibited the greatest sensitivity to the DNA-damaging treatments we tested was the ΔpolB2 ΔpolB3 combination, providing the first evidence of overlapping function for these two DNAPs in vivo. The results of our study strongly suggest that PolB1 is responsible for the DNA replication of both the leading and lagging strands and is sufficient to complete the repair of most DNA damage under normal growth conditions in S. acidocaldarius.},
}
@article {pmid33424811,
year = {2020},
author = {Thongprem, P and Evison, SEF and Hurst, GDD and Otti, O},
title = {Transmission, Tropism, and Biological Impacts of Torix Rickettsia in the Common Bed Bug Cimex lectularius (Hemiptera: Cimicidae).},
journal = {Frontiers in microbiology},
volume = {11},
number = {},
pages = {608763},
doi = {10.3389/fmicb.2020.608763},
pmid = {33424811},
issn = {1664-302X},
abstract = {The torix group of Rickettsia have been recorded from a wide assemblage of invertebrates, but details of transmission and biological impacts on the host have rarely been established. The common bed bug (Cimex lectularius) is a hemipteran insect which lives as an obligatory hematophagous pest of humans and is host to a primary Wolbachia symbiont and two facultative symbionts, a BEV-like symbiont, and a torix group Rickettsia. In this study, we first note the presence of a single Rickettsia strain in multiple laboratory bed bug isolates derived from Europe and Africa. Importantly, we discovered that the Rickettsia has segregated in two laboratory strains, providing infected and uninfected isogenic lines for study. Crosses with these lines established transmission was purely maternal. Fluorescence in-situ hybridization analysis indicates Rickettsia infection in oocytes, bacteriomes, and other somatic tissues. We found no evidence that Rickettsia infection was associated with sex ratio distortion activity, but Rickettsia infected individuals developed from first instar to adult more slowly. The impact of Rickettsia on fecundity and fertility resulted in infected females producing fewer fertile eggs. However, we could not find any evidence for cytoplasmic incompatibility associated with Rickettsia presence. These data imply the existence of an unknown benefit to C. lectularius carrying Rickettsia that awaits further research.},
}
@article {pmid33424808,
year = {2020},
author = {Doremus, MR and Stouthamer, CM and Kelly, SE and Schmitz-Esser, S and Hunter, MS},
title = {Cardinium Localization During Its Parasitoid Wasp Host's Development Provides Insights Into Cytoplasmic Incompatibility.},
journal = {Frontiers in microbiology},
volume = {11},
number = {},
pages = {606399},
doi = {10.3389/fmicb.2020.606399},
pmid = {33424808},
issn = {1664-302X},
abstract = {Arthropods harbor heritable intracellular symbionts that may manipulate host reproduction to favor symbiont transmission. In cytoplasmic incompatibility (CI), the symbiont sabotages the reproduction of infected males such that high levels of offspring mortality result when they mate with uninfected females. In crosses with infected males and infected females, however (the "rescue" cross), normal numbers of offspring are produced. A common CI-inducing symbiont, Cardinium hertigii, causes variable levels of CI mortality in the parasitoid wasp, Encarsia suzannae. Previous work correlated CI-induced mortality with male development time in this system, although the timing of Cardinium CI-induction and the relationship between development time and CI mortality was not well understood. Here, using a combination of crosses, manipulation of development time, and fluorescence microscopy, we identify the localization and the timing of the CI-induction step in the Cardinium-E. suzannae system. Antibiotic treatment of adult Cardinium-infected males did not reduce the mortality associated with the CI phenotype, suggesting that CI-alteration occurs prior to adulthood. Our results suggest that the alteration step occurs during the pupal period, and is limited by the duration of pupal development: 1) Encarsia produces most sperm prior to adulthood, 2) FISH localization of Cardinium in testes showed an association with sperm nuclei throughout spermatogenesis but not with mature sperm, and 3) two methods of prolonging the pupal period (cool temperatures and the juvenile hormone analog methoprene) both caused greater CI mortality, suggesting the degree of alteration is limited by the duration of the pupal stage. Based on these results, we compare two models for potential mechanisms of Cardinium sperm modification in the context of what is known about analogous mechanisms of Wolbachia, a more extensively studied CI-inducing symbiont.},
}
@article {pmid33424333,
year = {2021},
author = {Sayara, T and Khayat, S and Saleh, J and Van Der Steen, P},
title = {Evaluation of the effect of reaction time on nutrients removal from secondary effluent of wastewater: Field demonstrations using algal-bacterial photobioreactors.},
journal = {Saudi journal of biological sciences},
volume = {28},
number = {1},
pages = {504-511},
doi = {10.1016/j.sjbs.2020.10.035},
pmid = {33424333},
issn = {1319-562X},
abstract = {Real field demonstrations to assess the removal efficiency of nutrients and organic matter from domestic wastewater were carried out using algal-bacterial photobioreactors. The reactors which consisted of three basins of 200 L were fed with secondary effluent of domestic wastewater and operated under natural day light/dark cycles. The results demonstrated that reaction time (RT) has a substantial role on the whole process performance. Whereas inoculation with nitrifiers affected the process only in some aspects. The enhancement in the dissolved oxygen production rate (1.15 mg O2. L-1.h-1) was in alignment with growing higher algal biomass concentrations due to the increase in RT. COD removal rates were significantly increased (p < 0.05) with increasing the RT, and removal rates of 27%, 46% and 50% were obtained under RTs of 2, 3 and 4hrs. respectively. Meanwhile, 30%, 84% and 95% of the phosphorus was removed under the same studied RTs. No significant effect was recorded due to the addition of nitrifying bacteria on the removal of both COD and phosphorus. Ammonium (NH4+-N) removal rates were also increased with increasing RT and by the addition of nitrifiers, such that removal rates of 13%, 21% and 31% were obtained in basins inoculated with nitrifiers, but 11%, 14% and 19.5% were obtained in non-inoculated basins under RT of 2, 3, and 4 hrs. respectively. These results provide some new insights into algal-bacterial symbiosis systems under real field conditions which could be helpful for further process development.},
}
@article {pmid33206703,
year = {2020},
author = {McLean, AHC and Parker, BJ},
title = {Variation in intrinsic resistance of pea aphids to parasitoid wasps: A transcriptomic basis.},
journal = {PloS one},
volume = {15},
number = {11},
pages = {e0242159},
pmid = {33206703},
issn = {1932-6203},
mesh = {Animals ; Aphids/*parasitology/*physiology ; Biological Evolution ; Genotype ; Host-Parasite Interactions ; Immunity, Innate ; Medicago sativa ; Phenotype ; RNA/analysis ; Sequence Analysis, DNA ; Symbiosis ; *Transcriptome ; Vicia faba ; Wasps/*physiology ; },
abstract = {Evolutionary interactions between parasitoid wasps and insect hosts have been well studied at the organismal level, but little is known about the molecular mechanisms that insects use to resist wasp parasitism. Here we study the interaction between a braconid wasp (Aphidius ervi) and its pea aphid host (Acyrthosiphon pisum). We first identify variation in resistance to wasp parasitism that can be attributed to aphid genotype. We then use transcriptome sequencing to identify genes in the aphid genome that are differentially expressed at an early stage of parasitism, and we compare these patterns in highly resistant and susceptible aphid host lines. We find that resistant genotypes are upregulating genes involved in carbohydrate metabolism and several key innate immune system genes in response to parasitism, but that this response seems to be weaker in susceptible aphid genotypes. Together, our results provide a first look into the complex molecular mechanisms that underlie aphid resistance to wasp parasitism and contribute to a broader understanding of how resistance mechanisms evolve in natural populations.},
}
@article {pmid33046719,
year = {2020},
author = {Forsman, ZH and Ritson-Williams, R and Tisthammer, KH and Knapp, ISS and Toonen, RJ},
title = {Host-symbiont coevolution, cryptic structure, and bleaching susceptibility, in a coral species complex (Scleractinia; Poritidae).},
journal = {Scientific reports},
volume = {10},
number = {1},
pages = {16995},
pmid = {33046719},
issn = {2045-2322},
mesh = {Animals ; Anthozoa/*physiology ; Biological Evolution ; Coral Reefs ; Hawaii ; Host Adaptation ; Metagenomics/*methods ; Species Specificity ; Symbiosis/*genetics ; },
abstract = {The 'species' is a key concept for conservation and evolutionary biology, yet the lines between population and species-level variation are often blurred, especially for corals. The 'Porites lobata species complex' consists of branching and mounding corals that form reefs across the Pacific. We used reduced representation meta-genomic sequencing to examine genetic relationships within this species complex and to identify candidate loci associated with colony morphology, cryptic genetic structure, and apparent bleaching susceptibility. We compared existing Porites data with bleached and unbleached colonies of the branching coral P. compressa collected in Kāne'ohe Bay Hawai'i during the 2015 coral bleaching event. Loci that mapped to coral, symbiont, and microbial references revealed genetic structure consistent with recent host-symbiont co-evolution. Cryptic genetic clades were resolved that previous work has associated with distance from shore, but no genetic structure was associated with bleaching. We identified many candidate loci associated with morphospecies, including candidate host and symbiont loci with fixed differences between branching and mounding corals. We also found many loci associated with cryptic genetic structure, yet relatively few loci associated with bleaching. Recent host-symbiont co-evolution and rapid diversification suggests that variation and therefore the capacity of these corals to adapt may be underappreciated.},
}
@article {pmid32731255,
year = {2020},
author = {Wu, SE and Hashimoto-Hill, S and Woo, V and Eshleman, EM and Whitt, J and Engleman, L and Karns, R and Denson, LA and Haslam, DB and Alenghat, T},
title = {Microbiota-derived metabolite promotes HDAC3 activity in the gut.},
journal = {Nature},
volume = {586},
number = {7827},
pages = {108-112},
pmid = {32731255},
issn = {1476-4687},
support = {R01 DK098231/DK/NIDDK NIH HHS/United States ; P30 DK078392/DK/NIDDK NIH HHS/United States ; R01 DK116868/DK/NIDDK NIH HHS/United States ; R01 DK114123/DK/NIDDK NIH HHS/United States ; R56 DK098231/DK/NIDDK NIH HHS/United States ; F32 AI147591/AI/NIAID NIH HHS/United States ; },
mesh = {Animals ; Gastrointestinal Microbiome/*physiology ; Histone Deacetylases/*metabolism ; Humans ; Inositol 1,4,5-Trisphosphate/*metabolism ; Intestinal Mucosa/cytology/enzymology/metabolism/pathology ; Intestines/cytology/*enzymology/*microbiology/pathology ; Mice ; Mice, Inbred C57BL ; Organoids/enzymology/metabolism/pathology ; Phytic Acid/*metabolism ; Symbiosis ; },
abstract = {The coevolution of mammalian hosts and their beneficial commensal microbes has led to development of symbiotic host-microbiota relationships1. Epigenetic machinery permits mammalian cells to integrate environmental signals2; however, how these pathways are fine-tuned by diverse cues from commensal bacteria is not well understood. Here we reveal a highly selective pathway through which microbiota-derived inositol phosphate regulates histone deacetylase 3 (HDAC3) activity in the intestine. Despite the abundant presence of HDAC inhibitors such as butyrate in the intestine, we found that HDAC3 activity was sharply increased in intestinal epithelial cells of microbiota-replete mice compared with germ-free mice. This divergence was reconciled by the finding that commensal bacteria, including Escherichia coli, stimulated HDAC activity through metabolism of phytate and production of inositol-1,4,5-trisphosphate (InsP3). Both intestinal exposure to InsP3 and phytate ingestion promoted recovery following intestinal damage. Of note, InsP3 also induced growth of intestinal organoids derived from human tissue, stimulated HDAC3-dependent proliferation and countered butyrate inhibition of colonic growth. Collectively, these results show that InsP3 is a microbiota-derived metabolite that activates a mammalian histone deacetylase to promote epithelial repair. Thus, HDAC3 represents a convergent epigenetic sensor of distinct metabolites that calibrates host responses to diverse microbial signals.},
}
@article {pmid32572104,
year = {2020},
author = {Wu, WL and Hsiao, YY and Lu, HC and Liang, CK and Fu, CH and Huang, TH and Chuang, MH and Chen, LJ and Liu, ZJ and Tsai, WC},
title = {Expression regulation of MALATE SYNTHASE involved in glyoxylate cycle during protocorm development in Phalaenopsis aphrodite (Orchidaceae).},
journal = {Scientific reports},
volume = {10},
number = {1},
pages = {10123},
pmid = {32572104},
issn = {2045-2322},
mesh = {Carbohydrate Metabolism ; Gene Expression/genetics ; Gene Expression Regulation, Plant/genetics ; Germination ; Glyoxylates/metabolism ; Malate Synthase/*genetics/*metabolism ; Orchidaceae/*genetics/metabolism ; Seedlings/growth & development ; Seeds/physiology ; Symbiosis ; Transcription Factors/genetics ; Transcriptome ; },
abstract = {Orchid (Orchidaceae) is one of the largest families in angiosperms and presents exceptional diversity in lifestyle. Their unique reproductive characteristics of orchid are attracted by scientist for centuries. One of the synapomorphies of orchid plants is that their seeds do not contain endosperm. Lipids are used as major energy storage in orchid seeds. However, regulation and mobilization of lipid usage during early seedling (protocorm) stage of orchid is not understood. In this study, we compared transcriptomes from developing Phalaenopsis aphrodite protocorms grown on 1/2-strength MS medium with sucrose. The expression of P. aphrodite MALATE SYNTHASE (PaMLS), involved in the glyoxylate cycle, was significantly decreased from 4 days after incubation (DAI) to 7 DAI. On real-time RT-PCR, both P. aphrodite ISOCITRATE LYASE (PaICL) and PaMLS were down-regulated during protocorm development and suppressed by sucrose treatment. In addition, several genes encoding transcription factors regulating PaMLS expression were identified. A gene encoding homeobox transcription factor (named PaHB5) was involved in positive regulation of PaMLS. This study showed that sucrose regulates the glyoxylate cycle during orchid protocorm development in asymbiotic germination and provides new insights into the transcription factors involved in the regulation of malate synthase expression.},
}
@article {pmid32488494,
year = {2020},
author = {Rana, KL and Kour, D and Kaur, T and Devi, R and Yadav, AN and Yadav, N and Dhaliwal, HS and Saxena, AK},
title = {Endophytic microbes: biodiversity, plant growth-promoting mechanisms and potential applications for agricultural sustainability.},
journal = {Antonie van Leeuwenhoek},
volume = {113},
number = {8},
pages = {1075-1107},
pmid = {32488494},
issn = {1572-9699},
support = {Development of microbial consortium as bio-inoculants for drought//Department of Environmental and Science/ ; low temperature growing crops for organic farming in Himachal Pradesh//Department of Environmental and Science/ ; },
mesh = {Agriculture/methods ; Bacteria/*classification ; *Biodiversity ; Crops, Agricultural/*microbiology ; Endophytes/*classification/enzymology/*physiology ; Nitrogen Fixation ; *Plant Development ; Plant Growth Regulators ; Plant Roots/microbiology ; Symbiosis ; },
abstract = {Endophytic microbes are known to live asymptomatically inside their host throughout different stages of their life cycle and play crucial roles in the growth, development, fitness, and diversification of plants. The plant-endophyte association ranges from mutualism to pathogenicity. These microbes help the host to combat a diverse array of biotic and abiotic stressful conditions. Endophytic microbes play a major role in the growth promotion of their host by solubilizing of macronutrients such as phosphorous, potassium, and zinc; fixing of atmospheric nitrogen, synthesizing of phytohormones, siderophores, hydrogen cyanide, ammonia, and act as a biocontrol agent against wide array of phytopathogens. Endophytic microbes are beneficial to plants by directly promoting their growth or indirectly by inhibiting the growth of phytopathogens. Over a long period of co-evolution, endophytic microbes have attained the mechanism of synthesis of various hydrolytic enzymes such as pectinase, xylanases, cellulase, and proteinase which help in the penetration of endophytic microbes into tissues of plants. The effective usage of endophytic microbes in the form of bioinoculants reduce the usage of chemical fertilizers. Endophytic microbes belong to different phyla such as Actinobacteria, Acidobacteria, Bacteroidetes, Deinococcus-thermus, Firmicutes, Proteobacteria, and Verrucomicrobia. The most predominant and studied endophytic bacteria belonged to Proteobacteria followed by Firmicutes and then by Actinobacteria. The most dominant among reported genera in most of the leguminous and non-leguminous plants are Bacillus, Pseudomonas, Fusarium, Burkholderia, Rhizobium, and Klebsiella. In future, endophytic microbes have a wide range of potential for maintaining health of plant as well as environmental conditions for agricultural sustainability. The present review is focused on endophytic microbes, their diversity in leguminous as well as non-leguminous crops, biotechnological applications, and ability to promote the growth of plant for agro-environmental sustainability.},
}
@article {pmid32299221,
year = {2020},
author = {Sijbers, AM and Schoemaker, RJW and Nauta, A and Alkema, W},
title = {Revealing new leads for the impact of galacto-oligosaccharides on gut commensals and gut health benefits through text mining.},
journal = {Beneficial microbes},
volume = {11},
number = {3},
pages = {283-302},
doi = {10.3920/BM2019.0105},
pmid = {32299221},
issn = {1876-2891},
mesh = {Bifidobacterium/growth & development/physiology ; *Data Mining ; Feces/microbiology ; Fermentation ; *Galactose ; *Gastrointestinal Microbiome ; Health ; Humans ; Oligosaccharides/*administration & dosage ; Prebiotics/*analysis ; *Symbiosis ; },
abstract = {Galacto-oligosaccharides (GOS) are linked to various health benefits, such as the relief of symptoms of constipation. Part of the beneficial effects of GOS are thought to be the consequence of their bifidogenic effect, stimulating the growth of several Bifidobacterium species in vivo. However, GOS may exert additional effects by directly stimulating other bacterial species or by effects that bifidobacteria may have on other commensals in the gut. To get a better insight into the potential health effects induced by GOS, a good understanding of the gut ecosystem, the role of GOS and bifidobacteria is important. An increasing number of 16S DNA profiling and metagenomics studies have led to an expanding inventory of genera, species and strains that can be found in the human gut. To investigate the potential connection of these commensals with GOS and bifidobacteria, we have undertaken a text-mining study to chart the literature landscape around these commensals. To this end, we created controlled vocabularies describing GOS, a large set of gut commensals and a number of terms related to gut health, which were used to mine the entire MEDLINE database. Co-occurrence text-mining revealed that a large number of commensals found in the gut have a connection with Bifidobacterium species and with gut health effects. Word frequency analysis provided more insight into the functional nature of these relationships. Combined co-occurrence search results pointed to putative novel health benefits indirectly linked to bifidobacteria and GOS. The potential beneficial effects of GOS on the protection of epithelial function and epithelial barrier impairment and appendicitis are interesting novel leads. The text-mining approach reported here revealed a number of novel leads through which GOS could exert health effects and that could be investigated in dedicated studies.},
}
@article {pmid32130598,
year = {2020},
author = {Santos, JD and Vitorino, I and de la Cruz, M and Díaz, C and Cautain, B and Annang, F and Pérez-Moreno, G and Gonzalez, I and Tormo, JR and Martin, J and Vicente, MF and Lage, OM},
title = {Diketopiperazines and other bioactive compounds from bacterial symbionts of marine sponges.},
journal = {Antonie van Leeuwenhoek},
volume = {113},
number = {7},
pages = {875-887},
doi = {10.1007/s10482-020-01398-2},
pmid = {32130598},
issn = {1572-9699},
support = {UID/Multi/04423/2019//Fundação para a Ciência e a Tecnologia (PT)/ ; INP-2011-0016-PCT-010000-ACT6//Ministerio de Ciencia e Innovación/ ; },
mesh = {Animals ; Anti-Bacterial Agents/isolation & purification ; Antifungal Agents ; Antineoplastic Agents/pharmacology ; Antiparasitic Agents/pharmacology ; Bacteria/classification/*metabolism ; Cell Line, Tumor ; Diketopiperazines/chemistry/*isolation & purification/*metabolism/*pharmacology ; Enterococcus faecalis/drug effects ; Escherichia coli/drug effects ; Firmicutes/classification/metabolism ; Fungi/drug effects ; Hep G2 Cells/drug effects ; Humans ; Liver Neoplasms ; Methicillin-Resistant Staphylococcus aureus/drug effects ; Microbial Sensitivity Tests ; Porifera/*microbiology ; Symbiosis ; Trypanosoma cruzi/drug effects ; },
abstract = {Humanity faces great challenges, such as the rise of bacterial antibiotic resistance and cancer incidence. Thus, the discovery of novel therapeutics from underexplored environments, such as marine habitats, is fundamental. In this study, twelve strains from the phylum Firmicutes and thirty-four strains from the phylum Proteobacteria, isolated from marine sponges of the Erylus genus, collected in Portuguese waters, were tested for bioactivities and the secondary metabolites were characterised. Bioactivity screenings comprised antimicrobial, anti-fungal, anti-parasitic and anti-cancer assays. Selected bioactive extracts were further analysed for already described molecules through high performance liquid chromatography and mass spectrometry. Several bioactivities were observed against the fungus Aspergillusfumigatus, the bacteria (methicillin-resistant Staphylococcus aureus and Escherichia coli), the human liver cancer cell line HepG2 and the parasite Trypanosoma cruzi. Medium scale-up volume extracts confirmed anti-fungal activity by strains Proteus mirabilis #118_13 and Proteus sp. (JX006497) strain #118_20. Anti-parasitic activity was also confirmed in Enterococcus faecalis strain #118_3. Moreover, P. mirabilis #118_13 showed bioactivity in human melanoma cell line A2058 and the human hepatocellular carcinoma cell line HepG2. The dereplication of bioactive extracts showed the existence of a variety of secondary metabolites, with some unidentifiable molecules. This work shows that bacterial communities of sponges are indeed good candidates for drug discovery and, as far as we know, we describe anti-parasitic activity of a strain of E. faecalis and the presence of diketopiperazines in Proteus genus for the first time.},
}
@article {pmid33423360,
year = {2021},
author = {Gong, Z and Han, GZ},
title = {Flourishing in Water: The Early Evolution and Diversification of Plant Receptor-like Kinases.},
journal = {The Plant journal : for cell and molecular biology},
volume = {},
number = {},
pages = {},
doi = {10.1111/tpj.15157},
pmid = {33423360},
issn = {1365-313X},
abstract = {Receptor-like kinases (RLKs) play significant roles in mediating innate immunity and development of plants. The evolution of plant RLKs has been characterized by extensive variation in copy numbers and domain configurations. However, much remains unknown about the origin, evolution, and early diversification of plant RLKs. Here, we perform phylogenomic analyses of RLKs across plants (Archaeplastida), including embryophytes, charophytes, chlorophytes, prasinodermaphytes, glaucophytes, and rhodophytes. We identify the presence of RLKs in all the streptophytes (land plants and charophytes), nine out of 18 chlorophytes, one prasinodermaphyte, and one glaucophyte, but not in rhodophytes. Interestingly, the copy number of RLKs increased drastically in streptophytes after the split of the clade of Mesostigmatophyceae and Chlorokybophyceae and other streptophytes. Moreover, phylogenetic analyses suggest RLKs from charophytes form diverse distinct clusters, and are dispersed along the diversity of land plant RLKs, indicating that RLKs have extensively diversified in charophytes and charophyte RLKs seeded the major diversity of land plant RLKs. We identify at least 81 and 76 different kinase-associated domains for charophyte and land plant RLKs, 23 of which are shared, suggesting that RLKs might have evolved in a modular fashion through frequent domain gains or losses. We also detect signatures of positive selection for many charophyte RLK groups, indicating potential functions in host-microbe interaction. Taken together, our findings provide significant insights in the early evolution and diversification of plant RLKs and the ancient evolution of plant-microbe symbiosis.},
}
@article {pmid33419942,
year = {2021},
author = {Azargoshasb, S and Houwing, KHM and Roos, PR and van Leeuwen, SI and Boonekamp, M and Mazzone, E and Bauwens, K and Dell'Oglio, P and van Leeuwen, F and van Oosterom, MN},
title = {Optical navigation of a DROP-IN gamma probe as a means to strengthen the connection between robot-assisted and radioguided surgery.},
journal = {Journal of nuclear medicine : official publication, Society of Nuclear Medicine},
volume = {},
number = {},
pages = {},
doi = {10.2967/jnumed.120.259796},
pmid = {33419942},
issn = {1535-5667},
abstract = {Rationale: With translation of the DROP-IN gamma probe, radioguidance has advanced into laparoscopic robot-assisted surgery. 'GPS-like' navigation further enhances the symbiosis between nuclear medicine and surgery. Therefore, we developed a fluorescence-video-based tracking method that integrates the DROP-IN with navigated-robotic surgery. Methods: Fluorescent markers, integrated into the DROP-IN, were automatically detected using a daVinci Firefly laparoscope. Subsequently, a declipseSPECT-navigation platform calculated the DROP-IN's location within the surgical field. Using a phantom (n = 3), we pursued robotic-navigation on single-photon emission computed tomography/computed tomography (SPECT/CT), while intraoperative feasibility was validated during porcine surgery (n = 4). Results: Video-based tracking allowed for navigation of the DROP-IN towards all lesions detected on SPECT/CT (external-iliac and common-iliac artery regions). Augmented-reality visualization in the surgical console, indicated the distance to these lesions in real-time, confirmed by the DROP-IN read-out. Porcine surgery underlined the feasibility of the concept. Conclusion: Optical navigation of a DROP-IN probe provides a next step towards connecting nuclear-medicine with robotic surgery.},
}
@article {pmid33419736,
year = {2021},
author = {Shore, A and Day, RD and Stewart, JA and Burge, CA},
title = {Dichotomy between regulation of coral bacterial communities and calcification physiology under ocean acidification conditions.},
journal = {Applied and environmental microbiology},
volume = {},
number = {},
pages = {},
doi = {10.1128/AEM.02189-20},
pmid = {33419736},
issn = {1098-5336},
abstract = {Ocean acidification (OA) threatens the growth and function of coral reef ecosystems. A key component to coral health is the microbiome, but little is known about the impact of OA on coral microbiomes. A submarine CO2 vent at Maug Island in the Northern Marianas Islands provides a natural pH gradient to investigate coral responses to long-term OA conditions. Three coral species (Pocillopora eydouxi, Porites lobata, and Porites rus) were sampled from three sites where mean seawater pH is 8.04, 7.98, and 7.94. We characterized coral bacterial communities (using 16S rRNA gene sequencing) and determined pH of the extracellular calcifying fluid (ECF) (using skeletal boron isotopes) across the seawater pH gradient. Bacterial communities of both Porites species stabilized (decreases in community dispersion) with decreased seawater pH, coupled with large increases in the abundance of Endozoicomonas, an endosymbiont. P. lobata experienced a significant decrease in ECF pH near the vent, whereas P. rus experienced a trending decrease in ECF pH near the vent. By contrast, Pocillopora exhibited bacterial community destabilization (increases in community dispersion), with significant decreases in Endozoicomonas abundance, while its ECF pH remained unchanged across the pH gradient. Our study shows that OA has multiple consequences on Endozoicomonas abundance and suggests that Endozoicomonas abundance may be an indicator of coral response to OA. We reveal an interesting dichotomy between two facets of coral physiology (regulation of bacterial communities and regulation of calcification), highlighting the importance of multidisciplinary approaches to understanding coral health and function in a changing ocean.IMPORTANCEOcean acidification (OA) is a consequence of anthropogenic CO2 emissions that is negatively impacting marine ecosystems such as coral reefs. OA affects many aspects of coral physiology, including growth (i.e. calcification) and disrupting associated bacterial communities. Coral-associated bacteria are important for host health, but it remains unclear how coral-associated bacterial communities will respond to future OA conditions. We document changes in coral-associated bacterial communities and changes to calcification physiology with long-term exposure to decreases in seawater pH that are environmentally relevant under mid-range IPCC emission scenarios (0.1 pH units). We also find species-specific responses that may reflect different responses to long-term OA. In Pocillopora, calcification physiology was highly regulated despite changing seawater conditions. In Porites spp., changes in bacterial communities do not reflect a breakdown of coral-bacterial symbiosis. Insights into calcification and host-microbe interactions are critical to predicting the health and function of different coral taxa to future OA conditions.},
}
@article {pmid33419376,
year = {2020},
author = {Dolgikh, AV and Rudaya, ES and Dolgikh, EA},
title = {Identification of BELL Transcription Factors Involved in Nodule Initiation and Development in the Legumes Pisum sativum and Medicago truncatula.},
journal = {Plants (Basel, Switzerland)},
volume = {9},
number = {12},
pages = {},
doi = {10.3390/plants9121808},
pmid = {33419376},
issn = {2223-7747},
support = {16-16-10043 and 17-76-30016//Russian Science Foundation/ ; },
abstract = {Single three-amino acid loop extension (TALE) homeodomain proteins, including the KNOTTED-like (KNOX) and BEL-like (BELL) families in plants, usually work as heterodimeric transcription factor complexes to regulate different developmental processes, often via effects on phytohormonal pathways. Nitrogen-fixing nodule formation in legumes is regulated by different families of homeodomain transcription factors. Whereas the role of KNOX transcription factors in the control of symbiosis was studied early, BELL transcription factors have received less attention. Here, we report the identification and expression analysis of BELL genes in the legume plants Medicago truncatula and Pisum sativum, which are involved in regulating symbiosis initiation and development. A more precise analysis was performed for the most significantly upregulated PsBELL1-2 gene in pea. We found that the PsBELL1-2 transcription factor could be a potential partner of PsKNOX9. In addition, we showed that PsBELL1-2 can interact with the PsDELLA1 (LA) protein-regulator of the gibberellin pathway, which has a previously demonstrated important role in symbiosis development.},
}
@article {pmid33419044,
year = {2021},
author = {Inácio da Silva, LM and Dezordi, FZ and Paiva, MHS and Wallau, GL},
title = {Systematic Review of Wolbachia Symbiont Detection in Mosquitoes: An Entangled Topic about Methodological Power and True Symbiosis.},
journal = {Pathogens (Basel, Switzerland)},
volume = {10},
number = {1},
pages = {},
doi = {10.3390/pathogens10010039},
pmid = {33419044},
issn = {2076-0817},
abstract = {Wolbachia is an endosymbiotic bacterium that naturally infects several arthropods and nematode species. Wolbachia gained particular attention due to its impact on their host fitness and the capacity of specific Wolbachia strains in reducing pathogen vector and agricultural pest populations and pathogens transmission. Despite the success of mosquito/pathogen control programs using Wolbachia-infected mosquito release, little is known about the abundance and distribution of Wolbachia in most mosquito species, a crucial knowledge for planning and deployment of mosquito control programs and that can further improve our basic biology understanding of Wolbachia and host relationships. In this systematic review, Wolbachia was detected in only 30% of the mosquito species investigated. Fourteen percent of the species were considered positive by some studies and negative by others in different geographical regions, suggesting a variable infection rate and/or limitations of the Wolbachia detection methods employed. Eighty-three percent of the studies screened Wolbachia with only one technique. Our findings highlight that the assessment of Wolbachia using a single approach limited the inference of true Wolbachia infection in most of the studied species and that researchers should carefully choose complementary methodologies and consider different Wolbachia-mosquito population dynamics that may be a source of bias to ascertain the correct infectious status of the host species.},
}
@article {pmid33418397,
year = {2021},
author = {Diao, F and Dang, Z and Xu, J and Ding, S and Hao, B and Zhang, Z and Zhang, J and Wang, L and Guo, W},
title = {Effect of arbuscular mycorrhizal symbiosis on ion homeostasis and salt tolerance-related gene expression in halophyte Suaeda salsa under salt treatments.},
journal = {Microbiological research},
volume = {245},
number = {},
pages = {126688},
doi = {10.1016/j.micres.2020.126688},
pmid = {33418397},
issn = {1618-0623},
abstract = {Halophytes can remove large quantities of salts from saline soils, so their importance in ecology has received increasing attention. Preliminary studies have shown that arbuscular mycorrhizal (AM) fungi can improve the salt tolerance of halophytes. However, few studies have focused on the molecular mechanisms and effects of AM fungi in halophytes under different salt conditions. A pot experiment was carried out to investigate the effects of Funneliformis mosseae inoculation on growth, nutrient uptake, ion homeostasis and the expression of salt tolerance-related genes in Suaeda salsa under 0, 100, 200 and 400 mM NaCl. The results showed that F. mosseae promoted the growth of S. salsa and increased the shoot Ca2+ and Mg2+ concentrations under no-salt condition and high-salt condition. In addition, AM fungi increased the K+ concentration and maintained a high K+/Na+ ratio at 400 mM NaCl, while AM fungi decreased the K+ concentration and reduced the K+/Na+ ratio at 0 mM NaCl. AM fungi downregulated the expression of SsNHX1 in shoots and the expression of SsSOS1 in roots at 400 mM NaCl. These effects may decrease the compartmentation of Na+ into leaf vacuoles and restrict Na+ transport from roots to shoots, leading to an increase in root Na+ concentration. AM symbiosis upregulated the expression of SsSOS1 in shoots and downregulated the expression of SsSOS1 and SsNHX1 in roots at 100 mM NaCl. However, regulation of the genes (SsNHX1, SsSOS, SsVHA-B and SsPIP) was not significantly different with AM symbiosis at 0 mM or 200 mM NaCl. The results revealed that AM symbiosis might induce diverse modulation strategies in S. salsa, depending on external Na+ concentrations. These findings suggest that AM fungi may play significant ecological roles in the phytoremediation of salinized ecosystems.},
}
@article {pmid33418189,
year = {2021},
author = {Song, T and Sun, N and Dong, L and Cai, H},
title = {Enhanced alkali tolerance of rhizobia-inoculated alfalfa correlates with altered proteins and metabolic processes as well as decreased oxidative damage.},
journal = {Plant physiology and biochemistry : PPB},
volume = {159},
number = {},
pages = {301-311},
doi = {10.1016/j.plaphy.2020.12.021},
pmid = {33418189},
issn = {1873-2690},
abstract = {AIMS: Alkaline salt is one of the most devastating environmental factors limiting alfalfa productivity, however, the mechanisms underlying adaptation of alfalfa to alkaline remain unclear. Our aim is to investigate proteomic and metabolomic differences in growth and root of alfalfa under alkaline salt in Rhizobium-alfalfa symbiotic relationships.
METHODS: Rhizobium-inoculated and non-inoculated alfalfa plants were treated with 200 mmol/L NaHCO3 to investigate physiological, metabolic, and proteomic responses of root-nodule symbiosis under alkaline-induced stress, using an integrated approach combining metabolome and proteome analysis with measurements of physiological parameters.
RESULTS: The improved tolerance to alkalinity was observed in RI-plants compared with NI-plants. RI-plants accumulated more proline and MDH, and had higher antioxidant activity and relatively high RWC but low MDA content and low Na+/K+ ratio. The stress-related genes (P5CS, GST13, H+-Ppase, NADP-Me, SDH, and CS) were actively upregulated in RI plants under alkaline stress. In RI-plants, damage caused by alkaline stress was mainly alleviated by decreasing oxidative damage, enhancing the organic acid and amino acid metabolic processes, and scavenging harmful ROS by activating the phenylpropanoid biosynthetic pathway.
CONCLUSIONS: We revealed distinct proteins and metabolites related to alkali tolerance in RI-plants compared to NI-plants. Alkali tolerance of rhizobia-inoculated alfalfa was enhanced by altered proteins and metabolic processes as well as decreased oxidative damage.},
}
@article {pmid33418155,
year = {2021},
author = {Liu, Y and Liu, Y and Jiao, D and Lu, C and Lou, Y and Li, N and Wang, G and Wang, H},
title = {Synthesis and release of fatty acids under the interaction of Ulva pertusa and Heterosigma akashiwo by stable isotope analysis.},
journal = {Ecotoxicology and environmental safety},
volume = {210},
number = {},
pages = {111852},
doi = {10.1016/j.ecoenv.2020.111852},
pmid = {33418155},
issn = {1090-2414},
abstract = {Symbiosis of marine algae is inevitable in the marine environment, and species may occur interaction on the growth. In this study, the macroalgae Ulva pertusa and marine microalgae Heterosigma akashiwo were selected as target species to study the interaction mechanism between them. After the 8 days of co-cultivation, the inhibition on growth was observed for both of U. pertusa and H. akashiwo. Eight fatty acids in U. pertusa was detected, with the significant decrease in contents of polyunsaturated fatty acids (PUFAs) especially for C18:2, C18:3n-3 and C18:3n-6. Twelve fatty acids in H. akashiwo was detected, with the significant change for PUFAs. PUFA concentrations in the co-culture group were less than those in the mono-culture. Meanwhile the principal component analysis was conducted to insight into the interaction between U. pertusa and H. akashiwo by fatty acids content and carbon stable isotope ratio of fatty acids (δ13CFAs). Fatty acid content could not distinguish mono and co-culture. However, δ13CFAs could distinguish not only the culture time of algae, but also the living environment of algae. In addition, this study combined fatty acids content and δ13CFAs to explore the release of fatty acids by algae into the seawater. The C18:3n-3 was identified as the allelochemical released by U. pertusa to inhibit the growth of H. akashiwo. The ratio of δ13CFAs in seawater decreased. This study provides a theoretical basis for the symbiosis of marine algae, and a new method of compound-specific stable carbon isotopes was used to better explore the metabolism of fatty acids in algae.},
}
@article {pmid33417825,
year = {2021},
author = {Scharf, ME and Peterson, BF},
title = {A Century of Synergy in Termite Symbiosis Research: Linking the Past with New Genomic Insights.},
journal = {Annual review of entomology},
volume = {66},
number = {},
pages = {23-43},
doi = {10.1146/annurev-ento-022420-074746},
pmid = {33417825},
issn = {1545-4487},
abstract = {Termites have long been studied for their symbiotic associations with gut microbes. In the late nineteenth century, this relationship was poorly understood and captured the interest of parasitologists such as Joseph Leidy; this research led to that of twentieth-century biologists and entomologists including Cleveland, Hungate, Trager, and Lüscher. Early insights came via microscopy, organismal, and defaunation studies, which led to descriptions of microbes present, descriptions of the roles of symbionts in lignocellulose digestion, and early insights into energy gas utilization by the host termite. Focus then progressed to culture-dependent microbiology and biochemical studies of host-symbiont complementarity, which revealed specific microhabitat requirements for symbionts and noncellulosic mechanisms of symbiosis (e.g., N2 fixation). Today, knowledge on termite symbiosis has accrued exponentially thanks to omic technologies that reveal symbiont identities, functions, and interdependence, as well as intricacies of host-symbiont complementarity. Moving forward, the merging of classical twentieth-century approaches with evolving omic tools should provide even deeper insights into host-symbiont interplay.},
}
@article {pmid33417080,
year = {2021},
author = {Ogura-Tsujita, Y and Yukawa, T and Kinoshita, A},
title = {Evolutionary histories and mycorrhizal associations of mycoheterotrophic plants dependent on saprotrophic fungi.},
journal = {Journal of plant research},
volume = {},
number = {},
pages = {},
pmid = {33417080},
issn = {1618-0860},
abstract = {Mycoheterotrophic plants (MHPs) are leafless, achlorophyllous, and completely dependent on mycorrhizal fungi for their carbon supply. Mycorrhizal symbiosis is a mutualistic association with fungi that is undertaken by the majority of land plants, but mycoheterotrophy represents a breakdown of this mutualism in that plants parasitize fungi. Most MHPs are associated with fungi that are mycorrhizal with autotrophic plants, such as arbuscular mycorrhizal (AM) or ectomycorrhizal (ECM) fungi. Although these MHPs gain carbon via the common mycorrhizal network that links the surrounding autotrophic plants, some mycoheterotrophic lineages are associated with saprotrophic (SAP) fungi, which are free-living and decompose leaf litter and wood materials. Such MHPs are dependent on the forest carbon cycle, which involves the decomposition of wood debris and leaf litter, and have a unique biology and evolutionary history. MHPs associated with SAP fungi (SAP-MHPs) have to date been found only in the Orchidaceae and likely evolved independently at least nine times within that family. Phylogenetically divergent SAP Basidiomycota, mostly Agaricales but also Hymenochaetales, Polyporales, and others, are involved in mycoheterotrophy. The fungal specificity of SAP-MHPs varies from a highly specific association with a single fungal species to a broad range of interactions with multiple fungal orders. Establishment of symbiotic culture systems is indispensable for understanding the mechanisms underlying plant-fungus interactions and the conservation of MHPs. Symbiotic culture systems have been established for many SAP-MHP species as a pure culture of free-living SAP fungi is easier than that of biotrophic AM or ECM fungi. Culturable SAP-MHPs are useful research materials and will contribute to the advancement of plant science.},
}
@article {pmid32926791,
year = {2021},
author = {Li, H and Young, SE and Poulsen, M and Currie, CR},
title = {Symbiont-Mediated Digestion of Plant Biomass in Fungus-Farming Insects.},
journal = {Annual review of entomology},
volume = {66},
number = {},
pages = {297-316},
doi = {10.1146/annurev-ento-040920-061140},
pmid = {32926791},
issn = {1545-4487},
abstract = {Feeding on living or dead plant material is widespread in insects. Seminal work on termites and aphids has provided profound insights into the critical nutritional role that microbes play in plant-feeding insects. Some ants, beetles, and termites, among others, have evolved the ability to use microbes to gain indirect access to plant substrate through the farming of a fungus on which they feed. Recent genomic studies, including studies of insect hosts and fungal and bacterial symbionts, as well as metagenomics and proteomics, have provided important insights into plant biomass digestion across insect-fungal mutualisms. Not only do advances in understanding of the divergent and complementary functions of complex symbionts reveal the mechanism of how these herbivorous insects catabolize plant biomass, but these symbionts also represent a promising reservoir for novel carbohydrate-active enzyme discovery, which is of considerable biotechnological interest.},
}
@article {pmid31808246,
year = {2020},
author = {Mestre, A and Poulin, R and Hortal, J},
title = {A niche perspective on the range expansion of symbionts.},
journal = {Biological reviews of the Cambridge Philosophical Society},
volume = {95},
number = {2},
pages = {491-516},
doi = {10.1111/brv.12574},
pmid = {31808246},
issn = {1469-185X},
mesh = {Animals ; Biological Evolution ; Demography ; *Ecosystem ; Host-Parasite Interactions ; *Symbiosis ; },
abstract = {Range expansion results from complex eco-evolutionary processes where range dynamics and niche shifts interact in a novel physical space and/or environment, with scale playing a major role. Obligate symbionts (i.e. organisms permanently living on hosts) differ from free-living organisms in that they depend on strong biotic interactions with their hosts which alter their niche and spatial dynamics. A symbiotic lifestyle modifies organism-environment relationships across levels of organisation, from individuals to geographical ranges. These changes influence how symbionts experience colonisation and, by extension, range expansion. Here, we investigate the potential implications of a symbiotic lifestyle on range expansion capacity. We present a unified conceptual overview on range expansion of symbionts that integrates concepts grounded in niche and metapopulation theories. Overall, we explain how niche-driven and dispersal-driven processes govern symbiont range dynamics through their interaction across scales, from host switching to geographical range shifts. First, we describe a background framework for range dynamics based on metapopulation concepts applied to symbiont organisation levels. Then, we integrate metapopulation processes operating in the physical space with niche dynamics grounded in the environmental arena. For this purpose, we provide a definition of the biotope (i.e. living place) specific to symbionts as a hinge concept to link the physical and environmental spaces, wherein the biotope unit is a metapopulation patch (either a host individual or a land fragment). Further, we highlight the dual nature of the symbionts' niche, which is characterised by both host traits and the external environment, and define proper conceptual variants to provide a meaningful unification of niche, biotope and symbiont organisation levels. We also explore variation across systems in the relative relevance of both external environment and host traits to the symbiont's niche and their potential implications on range expansion. We describe in detail the potential mechanisms by which hosts, through their function as biotopes, could influence how some symbionts expand their range - depending on the life history and traits of both associates. From the spatial point of view, hosts can extend symbiont dispersal range via host-mediated dispersal, although the requirement for among-host dispersal can challenge symbiont range expansion. From the niche point of view, homeostatic properties of host bodies may allow symbiont populations to become insensitive to off-host environmental gradients during host-mediated dispersal. These two potential benefits of the symbiont-host interaction can enhance symbiont range expansion capacity. On the other hand, the central role of hosts governing the symbiont niche makes symbionts strongly dependent on the availability of suitable hosts. Thus, environmental, dispersal and biotic barriers faced by suitable hosts apply also to the symbiont, unless eventual opportunities for host switching allow the symbiont to expand its repertoire of suitable hosts (thus expanding its fundamental niche). Finally, symbionts can also improve their range expansion capacity through their impacts on hosts, via protecting their affiliated hosts from environmental harshness through biotic facilitation.},
}
@article {pmid33408228,
year = {2021},
author = {Renelies-Hamilton, J and Germer, K and Sillam-Dussès, D and Bodawatta, KH and Poulsen, M},
title = {Disentangling the Relative Roles of Vertical Transmission, Subsequent Colonizations, and Diet on Cockroach Microbiome Assembly.},
journal = {mSphere},
volume = {6},
number = {1},
pages = {},
pmid = {33408228},
issn = {2379-5042},
abstract = {A multitude of factors affect the assemblies of complex microbial communities associated with animal hosts, with implications for community flexibility, resilience, and long-term stability; however, their relative effects have rarely been deduced. Here, we use a tractable lab model to quantify the relative and combined effects of parental transmission (egg case microbiome present/reduced), gut inocula (cockroach versus termite gut provisioned), and varying diets (matched or unmatched with gut inoculum source) on gut microbiota structure of hatchlings of the omnivorous cockroach Shelfordella lateralis using 16S rRNA gene (rDNA) amplicon sequencing. We show that the presence of a preexisting bacterial community via vertical transmission of microbes on egg cases reduces subsequent microbial invasion, suggesting priority effects that allow initial colonizers to take a strong hold and which stabilize the microbiome. However, subsequent inoculation sources more strongly affect ultimate community composition and their ecological networks, with distinct host-taxon-of-origin effects on which bacteria establish. While this is so, communities respond flexibly to specific diets in ways that consequently impact predicted community functions. In conclusion, our findings suggest that inoculations drive communities toward different stable states depending on colonization and extinction events, through ecological host-microbe relations and interactions with other gut bacteria, while diet in parallel shapes the functional capabilities of these microbiomes. These effects may lead to consistent microbial communities that maximize the extended phenotype that the microbiota provides the host, particularly if microbes spend most of their lives in host-associated environments.IMPORTANCE When host fitness is dependent on gut microbiota, microbial community flexibility and reproducibility enhance host fitness by allowing fine-tuned environmental tracking and sufficient stability for host traits to evolve. Our findings lend support to the importance of vertically transmitted early-life microbiota as stabilizers, through interactions with potential colonizers, which may contribute to ensuring that the microbiota aligns within host fitness-enhancing parameters. Subsequent colonizations are driven by microbial composition of the sources available, and we confirm that host-taxon-of-origin affects stable subsequent communities, while communities at the same time retain sufficient flexibility to shift in response to available diets. Microbiome structure is thus the result of the relative impact and combined effects of inocula and fluctuations driven by environment-specific microbial sources and digestive needs. These affect short-term community structure on an ecological time scale but could ultimately shape host species specificities in microbiomes across evolutionary time, if environmental conditions prevail.},
}
@article {pmid33407518,
year = {2021},
author = {Kawade, A and Gore, M and Lele, P and Chavan, U and Pinnock, H and Smith, P and Juvekar, S and , },
title = {Interplaying role of healthcare activist and homemaker: a mixed-methods exploration of the workload of community health workers (Accredited Social Health Activists) in India.},
journal = {Human resources for health},
volume = {19},
number = {1},
pages = {7},
pmid = {33407518},
issn = {1478-4491},
support = {16/136/109//National Institute for Health Research/ ; },
abstract = {BACKGROUND: Globally, community health workers (CHWs) are integral contributors to many health systems. In India, Accredited Social Health Activists (ASHAs) have been deployed since 2005. Engaged in multiple health care activities, they are a key link between the health system and population. ASHAs are expected to participate in new health programmes prompting interest in their current workload from the perspective of the health system, community and their family.
METHODS: This mixed-methods design study was conducted in rural and tribal Primary Health Centers (PHCs), in Pune district, Western Maharashtra, India. All ASHAs affiliated with these PHCs were invited to participate in the quantitative study, those agreeing to contribute in-depth interviews (IDI) were enrolled in an additional qualitative study. Key informants' interviews were conducted with the Auxiliary Nurse Midwife (ANM), Block Facilitators (BFF) and Medical Officers (MO) of the same PHCs. Quantitative data were analysed using descriptive statistics. Qualitative data were analysed thematically.
RESULTS: We recruited 67 ASHAs from the two PHCs. ASHAs worked up to 20 h/week in their village of residence, serving populations of approximately 800-1200, embracing an increasing range of activities, despite a workload that contributed to feelings of being rushed and tiredness. They juggled household work, other paid jobs and their ASHA activities. Practical problems with travel added to time involved, especially in tribal areas where transport is lacking. Their sense of benefiting the community coupled with respect and recognition gained in village brought happiness and job satisfaction. They were willing to take on new tasks. ASHAs perceived themselves as 'voluntary community health workers' rather than as 'health activists".
CONCLUSIONS: ASHAs were struggling to balance their significant ASHA work and domestic tasks. They were proud of their role as CHWs and willing to take on new activities. Strategies to recruit, train, skills enhancement, incentivise, and retain ASHAs, need to be prioritised. Evolving attitudes to the advantages/disadvantages of current voluntary status and role of ASHAs need to be understood and addressed if ASHAs are to be remain a key component in achieving universal health coverage in India.},
}
@article {pmid33406726,
year = {2021},
author = {Day, DA and Smith, PMC},
title = {Iron Transport across Symbiotic Membranes of Nitrogen-Fixing Legumes.},
journal = {International journal of molecular sciences},
volume = {22},
number = {1},
pages = {},
doi = {10.3390/ijms22010432},
pmid = {33406726},
issn = {1422-0067},
support = {Industrial Transformation Research HUB IH140100013//Australian Research Council/ ; },
abstract = {Iron is an essential nutrient for the legume-rhizobia symbiosis and nitrogen-fixing bacteroids within root nodules of legumes have a very high demand for the metal. Within the infected cells of nodules, the bacteroids are surrounded by a plant membrane to form an organelle-like structure called the symbiosome. In this review, we focus on how iron is transported across the symbiosome membrane and accessed by the bacteroids.},
}
@article {pmid33406151,
year = {2021},
author = {Chevignon, G and Foray, V and Pérez-Jiménez, MM and Libro, S and Chung, M and Foster, JM and Landmann, F},
title = {Dual RNAseq analyses at soma and germline levels reveal evolutionary innovations in the elephantiasis-agent Brugia malayi, and adaptation of its Wolbachia endosymbionts.},
journal = {PLoS neglected tropical diseases},
volume = {15},
number = {1},
pages = {e0008935},
doi = {10.1371/journal.pntd.0008935},
pmid = {33406151},
issn = {1935-2735},
abstract = {Brugia malayi is a human filarial nematode responsible for elephantiasis, a debilitating condition that is part of a broader spectrum of diseases called filariasis, including lymphatic filariasis and river blindness. Almost all filarial nematode species infecting humans live in mutualism with Wolbachia endosymbionts, present in somatic hypodermal tissues but also in the female germline which ensures their vertical transmission to the nematode progeny. These α-proteobacteria potentially provision their host with essential metabolites and protect the parasite against the vertebrate immune response. In the absence of Wolbachia wBm, B. malayi females become sterile, and the filarial nematode lifespan is greatly reduced. In order to better comprehend this symbiosis, we investigated the adaptation of wBm to the host nematode soma and germline, and we characterized these cellular environments to highlight their specificities. Dual RNAseq experiments were performed at the tissue-specific and ovarian developmental stage levels, reaching the resolution of the germline mitotic proliferation and meiotic differentiation stages. We found that most wBm genes, including putative effectors, are not differentially regulated between infected tissues. However, two wBm genes involved in stress responses are upregulated in the hypodermal chords compared to the germline, indicating that this somatic tissue represents a harsh environment to which wBm have adapted. A comparison of the B. malayi and C. elegans germline transcriptomes reveals a poor conservation of genes involved in the production of oocytes, with the filarial germline proliferative zone relying on a majority of genes absent from C. elegans. The first orthology map of the B. malayi genome presented here, together with tissue-specific expression enrichment analyses, indicate that the early steps of oogenesis are a developmental process involving genes specific to filarial nematodes, that likely result from evolutionary innovations supporting the filarial parasitic lifestyle.},
}
@article {pmid33404552,
year = {2020},
author = {Huisman, R and Geurts, R},
title = {A Roadmap toward Engineered Nitrogen-Fixing Nodule Symbiosis.},
journal = {Plant communications},
volume = {1},
number = {1},
pages = {100019},
doi = {10.1016/j.xplc.2019.100019},
pmid = {33404552},
issn = {2590-3462},
abstract = {In the late 19th century, it was discovered that legumes can establish a root nodule endosymbiosis with nitrogen-fixing rhizobia. Soon after, the question was raised whether it is possible to transfer this trait to non-leguminous crops. In the past century, an ever-increasing amount of knowledge provided unique insights into the cellular, molecular, and genetic processes controlling this endosymbiosis. In addition, recent phylogenomic studies uncovered several genes that evolved to function specifically to control nodule formation and bacterial infection. However, despite this massive body of knowledge, the long-standing objective to engineer the nitrogen-fixing nodulation trait on non-leguminous crop plants has not been achieved yet. In this review, the unsolved questions and engineering strategies toward nitrogen-fixing nodulation in non-legume plants are discussed and highlighted.},
}
@article {pmid33404502,
year = {2021},
author = {Hinzke, T and Kleiner, M and Meister, M and Schlüter, R and Hentschker, C and Pané-Farré, J and Hildebrandt, P and Felbeck, H and Sievert, SM and Bonn, F and Völker, U and Becher, D and Schweder, T and Markert, S},
title = {Bacterial symbiont subpopulations have different roles in a deep-sea symbiosis.},
journal = {eLife},
volume = {10},
number = {},
pages = {},
doi = {10.7554/eLife.58371},
pmid = {33404502},
issn = {2050-084X},
support = {Chancellor's Faculty Excellence Program Cluster on Microbiomes and Complex Microbial Communities//NC State University/ ; Hatch project 1014212//National Institute of Food and Agriculture/ ; OCE-1131095//National Science Foundation/ ; The WHOI Investment in Science Fund//Woods Hole Oceanographic Institution/ ; MA6346/2-1//German Research Foundation/ ; OCE-1559198//National Science Foundation/ ; DFG Open Access Publication Fund: 393148499//German Research Foundation/ ; },
abstract = {The hydrothermal vent tubeworm Riftia pachyptila hosts a single 16S rRNA phylotype of intracellular sulfur-oxidizing symbionts, which vary considerably in cell morphology and exhibit a remarkable degree of physiological diversity and redundancy, even in the same host. To elucidate whether multiple metabolic routes are employed in the same cells or rather in distinct symbiont subpopulations, we enriched symbionts according to cell size by density gradient centrifugation. Metaproteomic analysis, microscopy, and flow cytometry strongly suggest that Riftia symbiont cells of different sizes represent metabolically dissimilar stages of a physiological differentiation process: While small symbionts actively divide and may establish cellular symbiont-host interaction, large symbionts apparently do not divide, but still replicate DNA, leading to DNA endoreduplication. Moreover, in large symbionts, carbon fixation and biomass production seem to be metabolic priorities. We propose that this division of labor between smaller and larger symbionts benefits the productivity of the symbiosis as a whole.},
}
@article {pmid33402818,
year = {2020},
author = {Gunawardana, D},
title = {An in silico Study of Two Transcription Factors Controlling Diazotrophic Fates of the Azolla Major Cyanobiont Trichormus azollae.},
journal = {Bioinformatics and biology insights},
volume = {14},
number = {},
pages = {1177932220977490},
doi = {10.1177/1177932220977490},
pmid = {33402818},
issn = {1177-9322},
abstract = {The cyanobiont Trichormus azollae lives symbiotically within fronds of the genus Azolla, and assimilates atmospheric nitrogen upon N-limitation, which earmarks this symbiosis to be a valuable biofertilizer in rice cultivation, among many other benefits that also include carbon sequestration. Therefore, studying the regulation of nitrogen fixation in Trichormus azollae is of great importance and benefit, especially the two topmost rungs of regulation, the NtcA and HetR transcription factors that are able to regulate the expression of myriads of downstream genes. Bioinformatics tools were used to zoom in on the NtcA and HetR transcription factors from Trichormus azollae to elaborate on what makes this particular cyanobiont different from other symbiotic as well as more distinct counterparts, in their commitment to nitrogen fixation. The utility of Azolla plants in tropical agriculture in particular merits the "top down N-regulation" by cyanobiont as a significant niche area of study, to make sense of superior N-fixing capabilities. The Trichormus azollae NtcA sequence was found as a phylogenetic outlier to horizontally infecting cyanobionts, which points to a distinct identity compared to symbiotic counterparts. There were borderline (60%-70%) levels of acceptable bootstrap support for the phylogenetic position of the Azolla cyanobiont's NtcA protein compared to other cyanobionts. Furthermore, the NtcA global nitrogen regulator in the Azolla cyanobiont has an extra cysteine at position 128, in addition to two other more conspicuous cysteines (positions, 157 and 164). A simulated homology model of the NtcA protein from Trichormus azollae, points to a single unique cysteine (Cysteine-128) as a key residue at the center of a lengthy C-helix, which forms a coiled-coil interface, through likely disulfide bond formation. Three cysteine (Cysteines: 128, 157, 164) architecture is exclusively found in Trichormus azollae and is absent in other cyanobacteria. A separate proline to alanine mutation in position 97-again exclusive to Trichormus azollae-appears to influence the flexibility of effector binding domain (EBD) to 2-oxoglutarate. The Trichormus azollae HetR sequence was found outside of horizontally-infecting cyanobiont sequences that formed a common clade, with the exception of the cyanobiont from the genus Cycas that formed one line of descent with the Trichormus azollae counterpart. Five (out of 6) serines predicted to be phosphorylated in the Trichormus azollae HetR sequence, are conserved in the Nostoc punctiforme counterpart, showcasing that phosphorylation is likley conserved in both vertically-transmitted and horizontally-acquired cyanobionts. A key Serine-127, within a conserved motif TSLTS, although conserved in heterocystous subsection IV and V cyanobacteria, are mutated in subsection III cyanobacteria that form trichomes but are unable to form heterocysts. I conclude that the NtcA protein from Trichormus azollae to be strategically divergent at specific amino acids that gives it an advantage in function as a 2-oxoglutarate-mediated transcription factor. The Trichormus azollae HetR transcription factor appears to possess parallel functionality to horizontally acquired counterparts. Especially Cysteine-128 in the NtcA transcription factor of the Azolla cyanobiont is an interesting proposition for future structure-function studies.},
}
@article {pmid33402640,
year = {2021},
author = {Chatla, C and Mishra, N and Jojula, M and Adepu, R and Puttala, M},
title = {A systematic review of utility of urine lipoarabinomannan in detecting tuberculosis among HIV-positive tuberculosis suspects.},
journal = {Lung India : official organ of Indian Chest Society},
volume = {38},
number = {1},
pages = {64-73},
doi = {10.4103/lungindia.lungindia_574_19},
pmid = {33402640},
issn = {0970-2113},
abstract = {Sputum smear microscopy (SSM), though regarded as an inexpensive and popular method for detecting tuberculosis (TB), lacks adequate sensitivity, specifically in adult people living with HIV/AIDS (PLHIV). Urine lipoarabinomannan (LAM) is a promising diagnostic tool among PLHIV with CD4 cell count < 200 cells/μl. We attempted to review all the studies undertaken in identifying the utility of urine LAM in diagnosing TB, especially among PLHIV. We searched PubMed, Google Scholar, and MEDLINE databases for studies reporting diagnostic utility of urine LAM status in PLHIV, published in the last 20 years till December 2019. The keywords used for searching were "Tuberculosis," "HIV/AIDS," "Diagnosis," "Screening" "Lipoarabinomannan," and "Urine." Our search resulted in 137 shortlisted citations, of which 67 related manuscripts were identified for detailed study. Based on inclusion and exclusion criteria, 37 studies were reviewed in detail. Average sample size of these studies was 464 (range = 81-2528; SD = 427). Crude average sensitivity of urine LAM in culture-confirmed TB cases was 44.1% (range = 8.3-93) while that of SSM was 38.6% (range = 14-65). However, sensitivity of urine LAM + SSM was 60.4% (range = 38.3-92.7), demonstrating the utility of SSM + urine LAM combination for detecting TB. Specificity was similar between urine LAM and SSM with 92.7% (range = 76-100) and 97.9% (range = 93.9-100), respectively. Majority of the studies demonstrated higher sensitivity of urine LAM in those with lesser the CD4 count, with immunocompromised and with debilitation who cannot produce self-expectorated sputum. We conclude that urine LAM is a potential diagnostic test in the algorithms involving immunocompromised, debilitated patients and specifically in PLHIV whose CD4 count is ≤100 cells/μl.},
}
@article {pmid33402066,
year = {2021},
author = {Epstein, B and Tiffin, P},
title = {Comparative genomics reveals high rates of horizontal transfer and strong purifying selection on rhizobial symbiosis genes.},
journal = {Proceedings. Biological sciences},
volume = {288},
number = {1942},
pages = {20201804},
doi = {10.1098/rspb.2020.1804},
pmid = {33402066},
issn = {1471-2954},
abstract = {Horizontal transfer (HT) alters the repertoire of symbiosis genes in rhizobial genomes and may play an important role in the on-going evolution of the rhizobia-legume symbiosis. To gain insight into the extent of HT of symbiosis genes with different functional roles (nodulation, N-fixation, host benefit and rhizobial fitness), we conducted comparative genomic and selection analyses of the full-genome sequences from 27 rhizobial genomes. We find that symbiosis genes experience high rates of HT among rhizobial lineages but also bear signatures of purifying selection (low Ka : Ks). HT and purifying selection appear to be particularly strong in genes involved in initiating the symbiosis (e.g. nodulation) and in genome-wide association candidates for mediating benefits provided to the host. These patterns are consistent with rhizobia adapting to the host environment through the loss and gain of symbiosis genes, but not with host-imposed positive selection driving divergence of symbiosis genes through recurring bouts of positive selection.},
}
@article {pmid33401672,
year = {2021},
author = {Yoshida, GJ},
title = {The Harmonious Interplay of Amino Acid and Monocarboxylate Transporters Induces the Robustness of Cancer Cells.},
journal = {Metabolites},
volume = {11},
number = {1},
pages = {},
doi = {10.3390/metabo11010027},
pmid = {33401672},
issn = {2218-1989},
support = {20K16340//Japan Society for the Promotion of Science/ ; },
abstract = {There is a growing body of evidence that metabolic reprogramming contributes to the acquisition and maintenance of robustness associated with malignancy. The fine regulation of expression levels of amino acid and monocarboxylate transporters enables cancer cells to exhibit the metabolic reprogramming that is responsible for therapeutic resistance. Amino acid transporters characterized by xCT (SLC7A11), ASCT2 (SLC1A5), and LAT1 (SLC7A5) function in the uptake and export of amino acids such as cystine and glutamine, thereby regulating glutathione synthesis, autophagy, and glutaminolysis. CD44 variant, a cancer stem-like cell marker, stabilizes the xCT antiporter at the cellular membrane, and tumor cells positive for xCT and/or ASCT2 are susceptible to sulfasalazine, a system Xc(-) inhibitor. Inhibiting the interaction between LAT1 and CD98 heavy chain prevents activation of the mammalian target of rapamycin (mTOR) complex 1 by glutamine and leucine. mTOR signaling regulated by LAT1 is a sensor of dynamic alterations in the nutrient tumor microenvironment. LAT1 is overexpressed in various malignancies and positively correlated with poor clinical outcome. Metabolic reprogramming of glutamine occurs often in cancer cells and manifests as ASCT2-mediated glutamine addiction. Monocarboxylate transporters (MCTs) mediate metabolic symbiosis, by which lactate in cancer cells under hypoxia is exported through MCT4 and imported by MCT1 in less hypoxic regions, where it is used as an oxidative metabolite. Differential expression patterns of transporters cause functional intratumoral heterogeneity leading to the therapeutic resistance. Therefore, metabolic reprogramming based on these transporters may be a promising therapeutic target. This review highlights the pathological function and therapeutic targets of transporters including xCT, ASCT2, LAT1, and MCT.},
}
@article {pmid33293528,
year = {2020},
author = {Claar, DC and Starko, S and Tietjen, KL and Epstein, HE and Cunning, R and Cobb, KM and Baker, AC and Gates, RD and Baum, JK},
title = {Dynamic symbioses reveal pathways to coral survival through prolonged heatwaves.},
journal = {Nature communications},
volume = {11},
number = {1},
pages = {6097},
pmid = {33293528},
issn = {2041-1723},
mesh = {Animals ; Anthozoa/microbiology/*physiology ; Coral Reefs ; Dinoflagellida/*physiology ; Heat-Shock Response ; Symbiosis/*physiology ; Thermotolerance/*physiology ; Tropical Climate/*adverse effects ; },
abstract = {Prospects for coral persistence through increasingly frequent and extended heatwaves seem bleak. Coral recovery from bleaching is only known to occur after temperatures return to normal, and mitigation of local stressors does not appear to augment coral survival. Capitalizing on a natural experiment in the equatorial Pacific, we track individual coral colonies at sites spanning a gradient of local anthropogenic disturbance through a tropical heatwave of unprecedented duration. Unexpectedly, some corals survived the event by recovering from bleaching while still at elevated temperatures. These corals initially had heat-sensitive algal symbiont communities, endured bleaching, and then recovered through proliferation of heat-tolerant symbionts. This pathway to survival only occurred in the absence of strong local stressors. In contrast, corals in highly disturbed areas were already dominated by heat-tolerant symbionts, and despite initially resisting bleaching, these corals had no survival advantage in one species and 3.3 times lower survival in the other. These unanticipated connections between disturbance, coral symbioses and heat stress resilience reveal multiple pathways to coral survival through future prolonged heatwaves.},
}
@article {pmid33156451,
year = {2021},
author = {Fritsche, Y and Lopes, ME and Selosse, MA and Stefenon, VM and Guerra, MP},
title = {Serendipita restingae sp. nov. (Sebacinales): an orchid mycorrhizal agaricomycete with wide host range.},
journal = {Mycorrhiza},
volume = {31},
number = {1},
pages = {1-15},
pmid = {33156451},
issn = {1432-1890},
support = {140562/2016-8//Conselho Nacional de Desenvolvimento Científico e Tecnológico (BR)/ ; 407974/2018-0//Conselho Nacional de Desenvolvimento Científico e Tecnológico (BR)/ ; 302798/2018-8//Conselho Nacional de Desenvolvimento Científico e Tecnológico (BR)/ ; },
mesh = {*Basidiomycota/genetics ; Host Specificity ; *Mycorrhizae ; *Orchidaceae ; Phylogeny ; Symbiosis ; },
abstract = {The Serendipitaceae family was erected in 2016 to accommodate the Sebacinales 'group B' clade, which contains peculiar species of cultivable root-associated fungi involved in symbiotic associations with a wide range of plant species. Here we report the isolation of a new Serendipita species which was obtained from protocorms of the terrestrial orchid Epidendrum fulgens cultivated in a greenhouse. This species is described based on phylogenetic analysis and on its microscopic and ultrastructural features in pure culture and in association with the host's protocorms. Its genome size was estimated using flow cytometry, and its capacity to promote the germination of E. fulgens seeds and to associate with roots of Arabidopsis thaliana was also investigated. Serendipita restingae sp. nov. is closely related to Serendipita sp. MAFF305841, isolated from Microtis rara (Orchidaceae), from which it differs by 14.2% in the ITS region and by 6.5% in the LSU region. It produces microsclerotia formed of non-monilioid hyphae, a feature that was not reported for the Sebacinales hitherto. Serendipita restingae promoted the germination of E. fulgens seeds, forming typical mycorrhizal pelotons within protocorm cells. It was also able to colonize the roots of Arabidopsis thaliana under in vitro conditions. Arabidopsis plants grown in association with S. restingae increased their biomass more than fourfold. Serendipita restingae is the first Serendipitaceae species described for the Americas.},
}
@article {pmid32346047,
year = {2020},
author = {Bassene, H and Niang, EHA and Fenollar, F and Doucoure, S and Faye, O and Raoult, D and Sokhna, C and Mediannikov, O},
title = {Role of plants in the transmission of Asaia sp., which potentially inhibit the Plasmodium sporogenic cycle in Anopheles mosquitoes.},
journal = {Scientific reports},
volume = {10},
number = {1},
pages = {7144},
pmid = {32346047},
issn = {2045-2322},
mesh = {Acetobacteraceae/*pathogenicity ; Animals ; Anopheles/*parasitology ; Female ; Malaria/prevention & control ; Male ; Plasmodium/pathogenicity/*physiology ; Symbiosis ; },
abstract = {Biological control against malaria and its transmission is currently a considerable challenge. Plant-associated bacteria of the genus Asaia are frequently found in nectarivorous arthropods, they thought to have a natural indirect action on the development of plasmodium in mosquitoes. However, virtually nothing is known about its natural cycle. Here, we show the role of nectar-producing plants in the hosting and dissemination of Asaia. We isolated Asaia strains from wild mosquitoes and flowers in Senegal and demonstrated the transmission of the bacteria from infected mosquitoes to sterile flowers and then to 26.6% of noninfected mosquitoes through nectar feeding. Thus, nectar-producing plants may naturally acquire Asaia and then colonize Anopheles mosquitoes through food-borne contamination. Finally, Asaia may play an indirect role in the reduction in the vectorial capacity of Anopheles mosquitoes in a natural environment (due to Plasmodium-antagonistic capacities of Asaia) and be used in the development of tools for Asaia-based paratransgenetic malaria control.},
}
@article {pmid32345105,
year = {2020},
author = {Abusleme, L and O'Gorman, H and Dutzan, N and Greenwell-Wild, T and Moutsopoulos, NM},
title = {Establishment and Stability of the Murine Oral Microbiome.},
journal = {Journal of dental research},
volume = {99},
number = {6},
pages = {721-729},
pmid = {32345105},
issn = {1544-0591},
mesh = {Animals ; Homeostasis ; Mice ; Mice, Inbred C57BL ; *Microbiota ; Mouth ; Symbiosis ; },
abstract = {Commensal microbiomes exert critical functions at barrier sites. In particular, establishment of the commensal microbiome after birth dictates immune functionality and tissue homeostasis at mucosal surfaces. To investigate the establishment and stability of the oral mucosal microbiome in mice, we evaluated oral microbiome communities shortly after birth, through adulthood, and up to 1 y of life in a controlled manner, using sequential oral samples from the same mice over time. We further evaluated transmissibility of oral microbiomes from parents and during cohousing experiments and evaluated susceptibility to oral inflammatory disease in mice harboring distinct microbiomes. Our work reveals basic principles in the establishment and stability of a health-associated oral microbiome after birth and provides insights that may be important for host-microbiome experimentation in animal models.},
}
@article {pmid32002992,
year = {2020},
author = {Moyano, J and Rodriguez-Cabal, MA and Nuñez, MA},
title = {Highly invasive tree species are more dependent on mutualisms.},
journal = {Ecology},
volume = {101},
number = {5},
pages = {e02997},
doi = {10.1002/ecy.2997},
pmid = {32002992},
issn = {1939-9170},
mesh = {Introduced Species ; *Mycorrhizae ; *Pinus ; Symbiosis ; Trees ; },
abstract = {Why some species become invasive while others do not remains an elusive question. It has been proposed that invasive species should depend less on mutualisms, because their spread would then be less constrained by the availability of mutualistic partners. We tested this idea with the genus Pinus, whose degree of invasiveness is known at the species level (being highly and negatively correlated with seed size), and which forms obligate mutualistic associations with ectomycorrhizal fungi (EMF). Mycorrhizal dependence is defined as the degree to which a plant needs the mycorrhizal fungi to show the maximum growth. In this regard, we use plant growth response to mycorrhizal fungi as a proxy for mycorrhizal dependence. We assessed the responsiveness of Pinus species to EMF using 1,206 contrasts published on 34 species, and matched these data with data on Pinus species invasiveness. Surprisingly, we found that species that are more invasive depend more on mutualisms (EMF). Seedling growth of species with smaller seeds benefited more from mutualisms, indicating a higher dependence. A higher reliance on EMF could be part of a strategy in which small-seeded species produce more seeds that can disperse further, and these species are likely to establish only if facilitated by mycorrhizal fungi. On the contrary, big-seeded species showed a lower dependence on EMF, which may be explained by their tolerance to stressful conditions during establishment. However, the limited dispersal of larger seeds may limit the spread of these species. We present strong evidence against a venerable belief in ecology that species that rely more on mutualisms are less prone to invade, and suggest that in certain circumstances greater reliance on mutualists can increase spread capacity.},
}
@article {pmid31810825,
year = {2020},
author = {Ghadimi, D and Yoness Hassan, MF and Fölster-Holst, R and Röcken, C and Ebsen, M and de Vrese, M and Heller, KJ},
title = {Regulation of hepcidin/iron-signalling pathway interactions by commensal bifidobateria plays an important role for the inhibition of metaflammation-related biomarkers.},
journal = {Immunobiology},
volume = {225},
number = {1},
pages = {151874},
doi = {10.1016/j.imbio.2019.11.009},
pmid = {31810825},
issn = {1878-3279},
mesh = {Bifidobacterium/*physiology ; Biomarkers/metabolism ; Coculture Techniques ; Diet, High-Fat ; HT29 Cells ; Hep G2 Cells ; Hepcidins/*metabolism ; Humans ; Inflammation/*metabolism ; Intestinal Mucosa/*immunology/microbiology ; Iron/*metabolism ; Lipopolysaccharides/metabolism ; NF-kappa B/metabolism ; Obesity/*immunology ; Oleic Acid/metabolism ; Signal Transduction ; Symbiosis ; Toll-Like Receptor 4/metabolism ; },
abstract = {Increased concentration of ferrous iron in the gastrointestinal tract increases the number of various pathogens and induces inflammation. LPS and/or high-fat diet-associated metaflammation is mediated through a quaternary receptor signaling complex containing iron-regulated pathway, IL-6/STAT inflammatory signaling pathway, hepcidin regulatory pathway, and common TLR4/NF-κB signaling pathway. We, therefore, investigated whether bifidobacteria directly or indirectly ameliorate LPS- and/or high-fat diet-associated metaflammation by reduction of intestinal iron concentration and/or the above-mentioned pathways.
MATERIAL & METHODS: We used a triple co-culture model of HT-29/B6, HMDM and HepG2 cells with apically added Bifidobacterium pseudolongum (DSMZ 20099), in the absence or presence of iron, LPS or oleate. Expressions of the biomarkers of interest were determined after 24 h incubation by TaqMan qRT-PCR, cell-based ELISA or Western blot.
RESULTS: Bifidobacteria inhibited LPS- and oleate-induced protein expression of inflammatory cytokines (IL-6, TNF-α) concomitantly with decreases in cellular TG and iron concentration. Exposure of co-cultured cells to bifidobacteria blocked NF-kB activity through inhibition of IκBα, p38 MAPK, and phosphorylation of NF-kB 65 subunit. TaqMan qRT-PCR and Western blot analysis revealed that bifidobacteria downregulated mRNA and protein expression of BMP6, DMT1, hepcidin, l-ferritin, ferroportin, IL-6, TfR1, Stat3, and TLR4 following exposure to excessive extracellular LPS, oleate and iron. However, the patterns of TLR2 mRNA and protein expression were quite the opposite of those of TLR4.
CONCLUSION: Commensal bifidobacteria ameliorate metaflammation/inflammatory responses to excessive extracellular LPS, oleate and iron through at least two molecular/signaling mechanisms: i. modulation of interactions of the hepcidin- and iron-signaling pathways via reduction of excess iron; ii. reduction of pro-inflammatory cytokines and hepcidin production through inhibition of the TLR4/NF-kB pathway. This may be a molecular basis by which commensal bifidobacteria enhance intrinsic cellular tolerance against excess consumption of energy-yielding substrates and/or free iron.},
}
@article {pmid31793324,
year = {2020},
author = {Fernández-Musoles, R and García Tejedor, A and Laparra, JM},
title = {Immunonutritional contribution of gut microbiota to fatty liver disease.},
journal = {Nutricion hospitalaria},
volume = {37},
number = {1},
pages = {193-206},
doi = {10.20960/nh.02775},
pmid = {31793324},
issn = {1699-5198},
mesh = {Animals ; Bile Acids and Salts/metabolism ; Choline Deficiency/complications ; Diabetes Mellitus, Type 2/complications ; Dysbiosis/complications/microbiology ; Exposome ; Fermentation ; *Gastrointestinal Microbiome ; Germ-Free Life ; Gram-Negative Bacteria/physiology ; Humans ; Immunity, Innate ; Metabolic Syndrome/complications ; Mice ; Non-alcoholic Fatty Liver Disease/etiology/immunology/*microbiology/prevention & control ; Obesity/complications/microbiology ; Prebiotics ; Probiotics ; Symbiosis ; Thinness/microbiology ; },
abstract = {Introduction: Non-alcoholic fatty liver disease (NAFLD) is indisputably the most widespread liver disease worldwide, leading to a significant increase in patient morbidity, mortality, and health care utilization. The gut microbiota and its genome (microbiome) have emerged as a novel modulator of the immunometabolic processes that NAFLD implies, but microbiota-targeted interventions have resulted both astounding and at the same time unsuccessful. The most relevant alteration appears to be the overgrowth of Gram-negative bacteria, characterized by an increased ratio of Firmicutes to Bacteroidetes, although current evidence indicates species- and strain-specific effects influencing energy harvest, the host's innate and adaptive immune systems, and epigenetic regulation as determinants of the immunomodulatory milieu in NAFLD. The genera Lactobacillus and Bifidobacterium deserve special attention since many of their probiotic strains are marketed for human consumption, even more so when considering that, in conjunction with prebiotics, they are potential modulators of gut microbiota composition and/or metabolic activity. Here, a better understanding of the major intestinal microbial factors with a detrimental or preventive role in NAFLD, and of the dynamic interplay between gut microbiome and host factors, appears crucial in defining the exposome for the prevention and treatment of NAFLD and associated diseases such as metabolic syndrome, type-2 diabetes, and obesity.},
}
@article {pmid31719642,
year = {2020},
author = {Rollenske, T and Macpherson, AJ},
title = {Anti-commensal Ig-from enormous diversity to clear function.},
journal = {Mucosal immunology},
volume = {13},
number = {1},
pages = {1-2},
doi = {10.1038/s41385-019-0223-8},
pmid = {31719642},
issn = {1935-3456},
mesh = {Animals ; Autoimmunity ; Biodiversity ; Cross Reactions ; Humans ; Immunity, Mucosal ; Immunoglobulins/*immunology ; Microbiota/*immunology ; Symbiosis ; },
}
@article {pmid31619761,
year = {2020},
author = {Ge, Y and Gong, M and Zadeh, M and Li, J and Abbott, JR and Li, W and Morel, L and Sonon, R and Supekar, NT and Azadi, P and Wang, Y and Jones, DP and Li, S and Mohamadzadeh, M},
title = {Regulating colonic dendritic cells by commensal glycosylated large surface layer protein A to sustain gut homeostasis against pathogenic inflammation.},
journal = {Mucosal immunology},
volume = {13},
number = {1},
pages = {34-46},
doi = {10.1038/s41385-019-0210-0},
pmid = {31619761},
issn = {1935-3456},
support = {R01 DK109560/DK/NIDDK NIH HHS/United States ; S10 OD018530/OD/NIH HHS/United States ; },
mesh = {Animals ; Bacterial Proteins/genetics/*metabolism ; Cell Adhesion Molecules/genetics/*metabolism ; Cell Differentiation ; Cells, Cultured ; Colitis/chemically induced/*immunology ; Colon/*immunology ; Dendritic Cells/*immunology ; Humans ; Inflammatory Bowel Diseases/*immunology ; Lectins, C-Type/genetics/*metabolism ; Listeria/*physiology ; Listeriosis/*immunology ; Lymphocyte Activation ; Mice ; Mice, Inbred C57BL ; Mice, Knockout ; Propionibacterium/*metabolism ; Protein Binding ; Receptors, Cell Surface/genetics/*metabolism ; Symbiosis ; T-Lymphocytes/*immunology ; },
abstract = {Microbial interaction with the host through sensing receptors, including SIGNR1, sustains intestinal homeostasis against pathogenic inflammation. The newly discovered commensal Propionibacterium strain, P. UF1, regulates the intestinal immunity against pathogen challenge. However, the molecular events driving intestinal phagocytic cell response, including colonic dendritic cells (DCs), by this bacterium are still elusive. Here, we demonstrate that the glycosylation of bacterial large surface layer protein A (LspA) by protein O-mannosyltransferase 1 (Pmt1) regulates the interaction with SIGNR1, resulting in the control of DC transcriptomic and metabolomic machineries. Programmed DCs promote protective T cell response to intestinal Listeria infection and resist chemically induced colitis in mice. Thus, our findings may highlight a novel molecular mechanism by which commensal surface glycosylation interacting with SIGNR1 directs the intestinal homeostasis to potentially protect the host against proinflammatory signals inducing colonic tissue damage.},
}
@article {pmid31413347,
year = {2020},
author = {Sterlin, D and Fadlallah, J and Slack, E and Gorochov, G},
title = {The antibody/microbiota interface in health and disease.},
journal = {Mucosal immunology},
volume = {13},
number = {1},
pages = {3-11},
doi = {10.1038/s41385-019-0192-y},
pmid = {31413347},
issn = {1935-3456},
mesh = {Animals ; Gastrointestinal Microbiome/*immunology ; Homeostasis ; Host Microbial Interactions/*immunology ; Humans ; Immunity, Mucosal ; Immunoglobulin A/immunology/*metabolism ; Immunoglobulin A, Secretory/biosynthesis/*immunology/metabolism ; Intestinal Mucosa/*innervation ; Symbiosis ; },
abstract = {The human intestine is densely colonized with commensal microbes that stimulate the immune system. While secretory Immunoglobulin (Ig) A is known to play a crucial role in gut microbiota compartmentalization, secretory IgM, and systemic IgG have recently been highlighted in host-microbiota interactions as well. In this review, we discuss important aspects of secretory IgA biology, but rather than focusing on mechanistic aspects of IgA impact on microbiota, we stress the current knowledge of systemic antibody responses to whole gut microbiota, in particular their generation, specificities, and function. We also provide a comprehensive picture of secretory IgM biology. Finally, therapeutic and diagnostic implications of these novel findings for the treatment of various diseases are outlined.},
}
@article {pmid33400553,
year = {2021},
author = {Li, J and Lu, Z and Yang, Y and Hou, J and Yuan, L and Chen, G and Wang, C and Jia, S and Feng, X and Zhu, S},
title = {Transcriptome Analysis Reveals the Symbiotic Mechanism of Ustilago esculenta-Induced Gall Formation of Zizania latifolia.},
journal = {Molecular plant-microbe interactions : MPMI},
volume = {},
number = {},
pages = {MPMI05200126R},
doi = {10.1094/MPMI-05-20-0126-R},
pmid = {33400553},
issn = {0894-0282},
abstract = {Zizania latifolia is a perennial aquatic vegetable, whose symbiosis with the fungus Ustilago esculenta (member of Basidiomycota, class Ustilaginaceae) results in the establishment of swollen gall formations. Here, we analyzed symbiotic relations of Z. latifolia and U. esculenta, using a triadimefon (TDF) treatment and transcriptome sequencing (RNA-seq). Specifically, accurately identify the whole growth cycle of Z. latifolia. Microstructure observations showed that the presence of U. esculenta could be clearly observed after gall formation but was absent after the TDF treatment. A total of 17,541 differentially expressed genes (DEGs) were identified, based on the transcriptome. According to gene ontology term and Kyoto Encyclopedia of Genes and Genomes pathway results, plant hormone signal transduction, and cell wall-loosening factors were all significantly enriched due to U. esculenta infecting Z. latifolia; relative expression levels of hormone-related genes were identified, of which downregulation of indole 3-acetic acid (IAA)-related DEGs was most pronounced in JB_D versus JB_B. The ultra-high performance liquid chromatography analysis revealed that IAA, zeatin+trans zeatin riboside, and gibberellin 3 were increased under U. esculenta infection. Based on our results, we proposed a hormone-cell wall loosening model to study the symbiotic mechanism of gall formation after U. esculenta infects Z. latifolia. Our study thus provides a new perspective for studying the physiological and molecular mechanisms of U. esculenta infection of Z. latifolia causing swollen gall formations as well as a theoretical basis for enhancing future yields of cultivated Z. latifolia.[Formula: see text] The author(s) have dedicated the work to the public domain under the Creative Commons CCO "No Rights Reserved" license by waiving all of his or her rights to the work worldwide under copyright law, including all related and neighboring rights, to the extent allowed by law.},
}
@article {pmid33097518,
year = {2021},
author = {Soukup, P and Větrovský, T and Stiblik, P and Votýpková, K and Chakraborty, A and Sillam-Dussès, D and Kolařík, M and Odriozola, I and Lo, N and Baldrian, P and Šobotník, J and Bourguignon, T},
title = {Termites Are Associated with External Species-Specific Bacterial Communities.},
journal = {Applied and environmental microbiology},
volume = {87},
number = {2},
pages = {},
pmid = {33097518},
issn = {1098-5336},
abstract = {All termites have established a wide range of associations with symbiotic microbes in their guts. Some termite species are also associated with microbes that grow in their nests, but the prevalence of these associations remains largely unknown. Here, we studied the bacterial communities associated with the termites and galleries of three wood-feeding termite species by using 16S rRNA gene amplicon sequencing. We found that the compositions of bacterial communities among termite bodies, termite galleries, and control wood fragments devoid of termite activities differ in a species-specific manner. Termite galleries were enriched in bacterial operational taxonomic units (OTUs) belonging to Rhizobiales and Actinobacteria, which were often shared by several termite species. The abundance of several bacterial OTUs, such as Bacillus, Clostridium, Corynebacterium, and Staphylococcus, was reduced in termite galleries. Our results demonstrate that both termite guts and termite galleries harbor unique bacterial communities.IMPORTANCE As is the case for all ecosystem engineers, termites impact their habitat by their activities, potentially affecting bacterial communities. Here, we studied three wood-feeding termite species and found that they influence the composition of the bacterial communities in their surrounding environment. Termite activities have positive effects on Rhizobiales and Actinobacteria abundance and negative effects on the abundance of several ubiquitous genera, such as Bacillus, Clostridium, Corynebacterium, and Staphylococcus Our results demonstrate that termite galleries harbor unique bacterial communities.},
}
@article {pmid32295161,
year = {2020},
author = {Xu, F and Cheng, R and Miao, S and Zhu, Y and Sun, Z and Qiu, L and Yang, J and Zhou, Y},
title = {Prior Toxoplasma Gondii Infection Ameliorates Liver Fibrosis Induced by Schistosoma Japonicum through Inhibiting Th2 Response and Improving Balance of Intestinal Flora in Mice.},
journal = {International journal of molecular sciences},
volume = {21},
number = {8},
pages = {},
pmid = {32295161},
issn = {1422-0067},
support = {BK20190597//Natural Science Foundation of Jiangsu Province/ ; WX18IIAN010//Wuxi Municipal Bureau on Science and Technology/ ; K2050205//Jiangnan University/ ; 2019M661729//Postdoctoral Research Foundation of China/ ; 81871268//National Natural Science Foundation of China/ ; 81373116//National Natural Science Foundation of China/ ; BL2014020//Clinical Medical Science and Technology of Jiangsu Province/ ; ZDXKA2016016//Health Project of Science and Education/ ; },
mesh = {Animals ; Biodiversity ; Coinfection ; Disease Models, Animal ; Disease Progression ; Disease Susceptibility ; *Gastrointestinal Microbiome ; Liver Cirrhosis/*complications/etiology/*pathology ; Liver Function Tests ; Lymphocyte Activation/immunology ; Mice ; *Schistosoma japonicum ; Symbiosis ; Th1 Cells/immunology/metabolism ; Th2 Cells/*metabolism ; Toxoplasmosis, Animal/*complications/*parasitology ; },
abstract = {Schistosomiasis is an immunopathogenic disease in which a T helper (Th) cell type 2-like response plays vital roles. Hepatic fibrosis is its main pathologic manifestations, which is the leading cause of hepatic cirrhosis. Co-infections of Schistosoma japonicum (Sj) with other pathogens are frequently encountered but are easily ignored in clinical studies, and effective therapeutic interventions are lacking. In this study, we explored the effect of Toxoplasma gondii (Tg) prior infection on Th1/Th2 response, community shifts in gut microbiome (GM), and the pathogenesis of schistosomiasis in murine hosts. Mice were prior infected with Tg before Sj infection. The effects of co-infection on Th1/Th2 response and hepatic fibrosis were analyzed. Furthermore, we investigated this issue by sequencing 16S rRNA from fecal specimens to define the GM profiles during co-infection. Tg prior infection markedly reduced the granuloma size and collagen deposit in livers against Sj infection. Prior infection promoted a shift toward Th1 immune response instead of Th2. Furthermore, Tg infection promoted the expansion of preponderant flora and Clostridiaceae was identified as a feature marker in the GM of the co-infection group. Redundancy analysis (RDA)/canonical correspondence analysis (CCA) results showed that liver fibrosis, Th1/Th2 cytokines were significantly correlated (P < 0.05) with the GM compositions. Tg infection inhibits hepatic fibrosis by downregulating Th2 immune response against Sj infection, and further promotes the GM shifts through "gut-liver axis" in the murine hosts. Our study may provide insights into potential anti-fibrosis strategies in co-infection individuals.},
}
@article {pmid32290414,
year = {2020},
author = {Matijašić, M and Meštrović, T and Paljetak, HČ and Perić, M and Barešić, A and Verbanac, D},
title = {Gut Microbiota beyond Bacteria-Mycobiome, Virome, Archaeome, and Eukaryotic Parasites in IBD.},
journal = {International journal of molecular sciences},
volume = {21},
number = {8},
pages = {},
pmid = {32290414},
issn = {1422-0067},
support = {IP-11-2013-5467//Hrvatska Zaklada za Znanost/ ; GA KK01.1.1.01.0008//European Regional Development Fund/ ; },
mesh = {Animals ; *Archaea ; *Bacteria ; Disease Susceptibility ; Dysbiosis ; Eukaryota ; *Gastrointestinal Microbiome ; Humans ; Inflammatory Bowel Diseases/etiology/metabolism/pathology ; *Mycobiome ; *Parasites ; Symbiosis ; *Virome ; },
abstract = {The human microbiota is a diverse microbial ecosystem associated with many beneficial physiological functions as well as numerous disease etiologies. Dominated by bacteria, the microbiota also includes commensal populations of fungi, viruses, archaea, and protists. Unlike bacterial microbiota, which was extensively studied in the past two decades, these non-bacterial microorganisms, their functional roles, and their interaction with one another or with host immune system have not been as widely explored. This review covers the recent findings on the non-bacterial communities of the human gastrointestinal microbiota and their involvement in health and disease, with particular focus on the pathophysiology of inflammatory bowel disease.},
}
@article {pmid32230931,
year = {2020},
author = {Leitão, AL and Costa, MC and Gabriel, AF and Enguita, FJ},
title = {Interspecies Communication in Holobionts by Non-Coding RNA Exchange.},
journal = {International journal of molecular sciences},
volume = {21},
number = {7},
pages = {},
pmid = {32230931},
issn = {1422-0067},
mesh = {Animals ; Anthozoa/physiology ; Bacteria ; Bacterial Physiological Phenomena ; Cell Communication/*genetics/*physiology ; Dysbiosis ; Mammals ; Metagenome ; MicroRNAs ; Microbiota/physiology ; Plant Physiological Phenomena ; Plants ; RNA, Untranslated/*genetics/*metabolism ; *Signal Transduction ; Symbiosis/genetics/physiology ; Transcriptome ; },
abstract = {Complex organisms are associations of different cells that coexist and collaborate creating a living consortium, the holobiont. The relationships between the holobiont members are essential for proper homeostasis of the organisms, and they are founded on the establishment of complex inter-connections between all the cells. Non-coding RNAs are regulatory molecules that can also act as communication signals between cells, being involved in either homeostasis or dysbiosis of the holobionts. Eukaryotic and prokaryotic cells can transmit signals via non-coding RNAs while using specific extracellular conveyors that travel to the target cell and can be translated into a regulatory response by dedicated molecular machinery. Within holobionts, non-coding RNA regulatory signaling is involved in symbiotic and pathogenic relationships among the cells. This review analyzes current knowledge regarding the role of non-coding RNAs in cell-to-cell communication, with a special focus on the signaling between cells in multi-organism consortia.},
}
@article {pmid33391669,
year = {2020},
author = {Parker, ES and Moczek, AP},
title = {Don't stand so close to me: Microbiota-facilitated enemy release dynamics in introduced Onthophagus taurus dung beetles.},
journal = {Ecology and evolution},
volume = {10},
number = {24},
pages = {13640-13648},
doi = {10.1002/ece3.6836},
pmid = {33391669},
issn = {2045-7758},
abstract = {Microbial symbionts can influence their hosts in stunningly diverse ways. Emerging research suggests that an underappreciated facet of these relationships is the influence microbes can have on their host's responses to novel, or stressful, environmental conditions. We sought to address these and related questions in populations resulting from the recent introduction and subsequent rapid range expansion of Onthophagus taurus dung beetles. Specifically, we manipulated both microbial communities and rearing temperature to detect signatures of developmental and life history differentiation in response to the local thermal conditions in two populations derived from the southern most (Florida) and northern most (Michigan) extremes of the exotic Eastern U.S. range of O. taurus. We then sought to determine the contributions, if any, of host-associated microbiota to this differentiation. We found that when reared under common garden conditions individuals from Florida and Michigan populations differed significantly in developmental performance measures and life history traits, consistent with population divergence. At the same time, and contrary to our predictions, we failed to find support for the hypothesis that animals perform better if reared at temperatures that match their location of origin and that performance differences may be mediated by host-associated microbiota. Instead, we found that microbiome swapping across host populations improved developmental performance in both populations, consistent with enemy release dynamics. We discuss the implications of our results for our understanding of the rapid spread of exotic O. taurus through the Eastern United States and the significance of symbiosis in host responses to novel environmental conditions more broadly.},
}
@article {pmid33391331,
year = {2020},
author = {Bonfante, P and Lanfranco, L and Salvioli di Fossalunga, A and Ghignone, S and Volpe, V and Fiorilli, V and Perotto, S and Balestrini, R and Genre, A},
title = {Editorial: Proceedings of iMMM 2019 - International Molecular Mycorrhiza Meeting.},
journal = {Frontiers in plant science},
volume = {11},
number = {},
pages = {627988},
doi = {10.3389/fpls.2020.627988},
pmid = {33391331},
issn = {1664-462X},
}
@article {pmid33391195,
year = {2020},
author = {Deka, D and Sonowal, S and Chikkaputtaiah, C and Velmurugan, N},
title = {Symbiotic Associations: Key Factors That Determine Physiology and Lipid Accumulation in Oleaginous Microorganisms.},
journal = {Frontiers in microbiology},
volume = {11},
number = {},
pages = {555312},
doi = {10.3389/fmicb.2020.555312},
pmid = {33391195},
issn = {1664-302X},
abstract = {Symbiosis naturally provides an opportunity for microorganisms to live together by mutual or one-way benefit. In symbiotic relationships, the microorganisms usually overcome the limitations of being free-living. Understanding the symbiotic relationships of oleaginous microorganisms provides potential route for the sustainable production of microbial-based alternative fuels. So far, several studies have been conducted in oleaginous microorganisms for the production of alternative fuels. However, some oleaginous microorganisms require high quantity of nutrients for their growth, and high level of energy and chemicals for harvest and separation of lipid bodies. Symbiotic associations can successfully be applied to address these issues. Of symbiotic associations, lichens and selective species of oleaginous endosymbiotic mucoromycotina have received substantial interest as better models to study the evolutionary relationships as well as single-cell oil production. Construction of artificial lichen system composed of cyanobacteria and oleaginous yeast has been achieved for sustainable production of lipids with minimum energy demand. Recently, endosymbiotic mucoromycotina species have been recognized as potential sources for biofuels. Studies found that endohyphal bacterium influences lipid profiling in endosymbiotic mucoromycotina species. Studies on the genetic factors related to oleaginous characteristics of endosymbiotic mucoromycotina species are scarce. In this regard, this review summarizes the different forms of symbiotic associations of oleaginous microorganisms and how symbiotic relationships are impacting the lipid formation in microorganisms. Further, the review also highlights the importance of evolutionary relationships and benefits of co-culturing (artificial symbiosis) approaches for sustainable production of biofuels.},
}
@article {pmid33391192,
year = {2020},
author = {Klarenberg, IJ and Keuschnig, C and Warshan, D and Jónsdóttir, IS and Vilhelmsson, O},
title = {The Total and Active Bacterial Community of the Chlorolichen Cetraria islandica and Its Response to Long-Term Warming in Sub-Arctic Tundra.},
journal = {Frontiers in microbiology},
volume = {11},
number = {},
pages = {540404},
doi = {10.3389/fmicb.2020.540404},
pmid = {33391192},
issn = {1664-302X},
abstract = {Lichens are traditionally defined as a symbiosis between a fungus and a green alga and or a cyanobacterium. This idea has been challenged by the discovery of bacterial communities inhabiting the lichen thalli. These bacteria are thought to contribute to the survival of lichens under extreme and changing environmental conditions. How these changing environmental conditions affect the lichen-associated bacterial community composition remains unclear. We describe the total (rDNA-based) and potentially metabolically active (rRNA-based) bacterial community of the lichen Cetaria islandica and its response to long-term warming using a 20-year warming experiment in an Icelandic sub-Arctic tundra. 16S rRNA and rDNA amplicon sequencing showed that the orders Acetobacterales (of the class Alphaproteobacteria) and Acidobacteriales (of the phylum Acidobacteria) dominated the bacterial community. Numerous amplicon sequence variants (ASVs) could only be detected in the potentially active community but not in the total community. Long-term warming led to increases in relative abundance of bacterial taxa on class, order and ASV level. Warming altered the relative abundance of ASVs of the most common bacterial genera, such as Granulicella and Endobacter. The potentially metabolically active bacterial community was also more responsive to warming than the total community. Our results suggest that the bacterial community of the lichen C. islandica is dominated by acidophilic taxa and harbors disproportionally active rare taxa. We also show for the first time that climate warming can lead to shifts in lichen-associated bacterial community composition.},
}
@article {pmid33211752,
year = {2020},
author = {Peter, C and Thoms, S and Koch, F and Sartoris, FJ and Bickmeyer, U},
title = {Sponge-derived Ageladine A affects the in vivo fluorescence emission spectra of microalgae.},
journal = {PloS one},
volume = {15},
number = {11},
pages = {e0242464},
pmid = {33211752},
issn = {1932-6203},
mesh = {Agelas/*chemistry ; Animals ; Chlorophyll A/chemistry ; Fluorescence ; Micrasterias/drug effects/metabolism ; Microalgae/*drug effects/metabolism ; Photosynthesis/drug effects/radiation effects ; Phycobilisomes/chemistry/drug effects ; Phycoerythrin/chemistry ; Pigments, Biological/chemistry ; Pyrroles/isolation & purification/*pharmacology ; Species Specificity ; Spectrometry, Fluorescence ; *Symbiosis ; Synechococcus/drug effects/metabolism ; Ultraviolet Rays ; },
abstract = {In several marine hosts of microalgae, fluorescent natural products may play an important role. While the ecological function of these compounds is not well understood, an interaction of these molecules with the photosynthesis of the symbionts has been suggested. In this study, the effect of Ageladine A (Ag A), a pH-dependent fluorophore found in sponges of the genus Agelas, on microalgal fluorescence was examined. The spectra showed an accumulation of Ag A within the cells, but with variable impacts on fluorescence. While in two Synechococcus strains, fluorescence of phycoerythrin increased significantly, the fluorescence of other Synechococcus strains was not affected. In four out of the five eukaryote species examined, chlorophyll a (Chl a) fluorescence intensity was modulated. In Tisochrysis lutea, for example, the position of the fluorescence emission maximum of Chl a was shifted. The variety of these effects of Ag A on microalgal fluorescence suggests that fluorophores derived from animals could play a crucial role in shaping the composition of marine host/symbiont systems.},
}
@article {pmid32546376,
year = {2020},
author = {Trumbo, S and Klassen, J},
title = {Editorial overview: Hidden players: microbes reshape the insect niche.},
journal = {Current opinion in insect science},
volume = {39},
number = {},
pages = {vi-ix},
doi = {10.1016/j.cois.2020.05.008},
pmid = {32546376},
issn = {2214-5753},
mesh = {Animals ; Bees/microbiology/parasitology ; Cockroaches/microbiology/parasitology ; Drosophila/microbiology ; *Insecta/microbiology/parasitology ; *Microbiota ; Mosquito Vectors/microbiology ; *Symbiosis ; },
}
@article {pmid32086000,
year = {2020},
author = {Lemoine, MM and Engl, T and Kaltenpoth, M},
title = {Microbial symbionts expanding or constraining abiotic niche space in insects.},
journal = {Current opinion in insect science},
volume = {39},
number = {},
pages = {14-20},
doi = {10.1016/j.cois.2020.01.003},
pmid = {32086000},
issn = {2214-5753},
mesh = {*Acclimatization ; Animal Shells/metabolism ; Animals ; Droughts ; Ecosystem ; Host Microbial Interactions ; Insecta/*microbiology/physiology ; Metals, Heavy/metabolism ; Microbiota ; Nitrogen Fixation ; Stress, Physiological ; Symbiosis/*physiology ; Temperature ; },
abstract = {In addition to their well-studied contributions to their host's nutrition, digestion, and defense, microbial symbionts of insects are increasingly found to affect their host's response toward abiotic stressors. In particular, symbiotic microbes can reduce or enhance tolerance to temperature extremes, improve desiccation resistance by aiding cuticle biosynthesis and sclerotization, and detoxify heavy metals. As such, individual symbionts or microbial communities can expand or constrain the abiotic niche space of their host and determine its adaptability to fluctuating environments. In light of the increasing impact of humans on climate and environment, a better understanding of host-microbe interactions is necessary to predict how different insect species will respond to changes in abiotic conditions.},
}
@article {pmid32078985,
year = {2020},
author = {Liberti, J and Engel, P},
title = {The gut microbiota - brain axis of insects.},
journal = {Current opinion in insect science},
volume = {39},
number = {},
pages = {6-13},
doi = {10.1016/j.cois.2020.01.004},
pmid = {32078985},
issn = {2214-5753},
mesh = {Animals ; Bees/*microbiology ; Behavior ; *Brain/microbiology/physiology ; Disease Models, Animal ; Drosophila/microbiology ; *Gastrointestinal Microbiome ; Host Microbial Interactions ; Hypocreales/pathogenicity ; Insecta/*microbiology ; Mental Disorders/microbiology ; Neurophysiology ; Symbiosis ; Wolbachia/pathogenicity ; },
abstract = {Research on the connections between gut microbes and the neurophysiology and behavior of their animal hosts has grown exponentially in just a few years. Most studies have focused on mammalian models as their relevance to human health is widely established. However, evidence is accumulating that insect behavior may be governed by molecular mechanisms that are partly homologous to those of mammals, and therefore relevant for the understanding of their behavioral dysfunctions. Social insects in particular may provide experimentally amenable models to disentangle the contributions of individual bacterial symbionts to the gut microbiota - brain axis. In this review, we summarize findings from recent research on the neurological and behavioral effects of the gut microbiota of insects and propose an integrated approach to unravel the extended behavioral phenotypes of gut microbes in the honey bee.},
}
@article {pmid31848755,
year = {2020},
author = {Kobiałka, M and Michalik, A and Świerczewski, D and Szklarzewicz, T},
title = {Complex symbiotic systems of two treehopper species: Centrotus cornutus (Linnaeus, 1758) and Gargara genistae (Fabricius, 1775) (Hemiptera: Cicadomorpha: Membracoidea: Membracidae).},
journal = {Protoplasma},
volume = {257},
number = {3},
pages = {819-831},
doi = {10.1007/s00709-019-01466-z},
pmid = {31848755},
issn = {1615-6102},
support = {K/ZDS/008068//Ministerstwo Nauki i Szkolnictwa Wyższego/ ; N18/DBS/000013//Ministerstwo Nauki i Szkolnictwa Wyższego/ ; },
mesh = {Animals ; Female ; Hemiptera ; Symbiosis/*physiology ; },
abstract = {The aim of the conducted study was to describe the symbiotic systems (the types of symbionts, distribution in the body of the host insect, the transovarial transmission between generations) of two treehoppers: Centrotus cornutus and Gargara genistae by means of microscopic and molecular techniques. We found that each of them is host to four species of bacteriome-inhabiting symbionts. In C. cornutus, ancestral bacterial symbionts Sulcia and Nasuia are accompanied by an additional symbiont-the bacterium Arsenophonus. In the bacteriomes of G. genistae, apart from Sulcia and Nasuia, bacterium Serratia is present. To our knowledge, this is the first report regarding the occurrence of Serratia as a symbiont in Hemiptera: Auchenorrhyncha. Bacteria Sulcia and Nasuia are harbored in their own bacteriocytes, whereas Arsenophonus and Serratia both inhabit their own bacteriocytes and also co-reside with bacteria Nasuia. We observed that both bacteria Arsenophonus and Serratia undergo autophagic degradation. We found that in both of the species examined, in the cytoplasm and nuclei of all of the cells of the bacteriome, bacteria Rickettsia are present. Our histological and ultrastructural observations revealed that all the bacteriome-associated symbionts of C. cornutus and G. genistae are transovarially transmitted from mother to offspring.},
}
@article {pmid33389542,
year = {2021},
author = {Wang, T and Cao, X and Wang, X and Chi, M and Li, L and Yao, N},
title = {Selection of suitable reference genes for quantitative real time PCR in different Tulasnella isolates and orchid-fungus symbiotic germination system.},
journal = {Molecular biology reports},
volume = {},
number = {},
pages = {},
pmid = {33389542},
issn = {1573-4978},
support = {31700547//National Natural Science Foundation of China/ ; BZ201901//Beijing Botanical Garden/ ; },
abstract = {Under natural conditions, mycorrhizal symbiosis accompanies nearly the entire life cycle of orchids from seed germination through to flowering and fruiting. Tulasnella-like orchid mycorrhizal fungi are the most common mycorrhizal fungi found in association with orchid species. Presently suitable reference genes have not been systematically selected for the quantification of gene expression via Real-Time Quantitative Reverse Transcription PCR (RT-qPCR). We evaluated 12 candidate Tulasnella genes in nine different Tulasnella isolates and in the Dendrobium-fungal symbiotic germination associations followed by statistical analysis using the programs Bestkeeper, geNorm, and Normfinder to analyze the expression stability of the individual genes. The results showed that the EF2, UBC, and PP2A genes had the highest rankings with relatively stable expression levels across the different genotypes and during the symbiotic seed germination process by the three programs, and may be suitable for RT-qPCR normalization. Furthermore, the gene encoding C-5 Sterol desaturase (C5SD) was selected to verify the reliability of EF2, UBC, and PP2A expression during the Tulasnella-Dendrobium symbiotic seed germination process. This study is the first systematic exploration of optimal reference genes for gene expression studies during the colonization of orchid seeds by the mycorrhizal fungus Tulasnella.},
}
@article {pmid33388854,
year = {2021},
author = {Chouvenc, T and Šobotník, J and Engel, MS and Bourguignon, T},
title = {Termite evolution: mutualistic associations, key innovations, and the rise of Termitidae.},
journal = {Cellular and molecular life sciences : CMLS},
volume = {},
number = {},
pages = {},
pmid = {33388854},
issn = {1420-9071},
support = {FLA-FLT 005660//USDA National Institute of Food and Agriculture/ ; 1754083//NSF-DEB/ ; IGA 20205014//Faculty of Tropical AgriSciences, Czech University of Life Sciences Prague/ ; },
abstract = {Termites are a clade of eusocial wood-feeding roaches with > 3000 described species. Eusociality emerged ~ 150 million years ago in the ancestor of modern termites, which, since then, have acquired and sometimes lost a series of adaptive traits defining of their evolution. Termites primarily feed on wood, and digest cellulose in association with their obligatory nutritional mutualistic gut microbes. Recent advances in our understanding of termite phylogenetic relationships have served to provide a tentative timeline for the emergence of innovative traits and their consequences on the ecological success of termites. While all "lower" termites rely on cellulolytic protists to digest wood, "higher" termites (Termitidae), which comprise ~ 70% of termite species, do not rely on protists for digestion. The loss of protists in Termitidae was a critical evolutionary step that fostered the emergence of novel traits, resulting in a diversification of morphology, diets, and niches to an extent unattained by "lower" termites. However, the mechanisms that led to the initial loss of protists and the succession of events that took place in the termite gut remain speculative. In this review, we provide an overview of the key innovative traits acquired by termites during their evolution, which ultimately set the stage for the emergence of "higher" termites. We then discuss two hypotheses concerning the loss of protists in Termitidae, either through an externalization of the digestion or a dietary transition. Finally, we argue that many aspects of termite evolution remain speculative, as most termite biological diversity and evolutionary trajectories have yet to be explored.},
}
@article {pmid33386853,
year = {2021},
author = {Ho-Plágaro, T and Huertas, R and Tamayo-Navarrete, MI and Blancaflor, E and Gavara, N and García-Garrido, JM},
title = {A novel putative microtubule-associated protein is involved in arbuscule development during arbuscular mycorrhiza formation.},
journal = {Plant & cell physiology},
volume = {},
number = {},
pages = {},
doi = {10.1093/pcp/pcaa159},
pmid = {33386853},
issn = {1471-9053},
abstract = {The formation of arbuscular mycorrhizal (AM) symbiosis requires plant root host cells to undergo major structural and functional reprogramming in order to house the highly branched AM fungal structure for the reciprocal exchange of nutrients. These morphological modifications are associated with cytoskeleton remodelling. However, molecular bases and the role of microtubules (MTs) and actin filament dynamics during AM formation are largely unknown. In this study, the tomato tsb gene, belonging to a Solanaceae group of genes encoding MT-associated proteins for pollen development, was found to be highly expressed in root cells containing arbuscules. At earlier stages of mycorrhizal development, tsb overexpression enhanced the formation of highly developed and transcriptionally active arbuscules, while tsb silencing hampers the formation of mature arbuscules and represses arbuscule functionality. However, at later stages of mycorrhizal colonization, tsb OE roots accumulate fully developed transcriptionally inactive arbuscules, suggesting that the collapse and turnover of arbuscules might be impaired by TSB accumulation. Imaging analysis of the MT cytoskeleton in cortex root cells overexpressing tsb revealed that TSB is involved in MT-bundling. Taken together, our results provide unprecedented insights into the role of novel MT-associated protein in MT rearrangements throughout the different stages of the arbuscule life cycle.},
}
@article {pmid33386621,
year = {2021},
author = {Zhang, M and Su, H and Gresshoff, PM and Ferguson, BJ},
title = {Shoot-derived miR2111 controls legume root and nodule development.},
journal = {Plant, cell & environment},
volume = {},
number = {},
pages = {},
doi = {10.1111/pce.13992},
pmid = {33386621},
issn = {1365-3040},
abstract = {Legumes control their nodule numbers through the Autoregulation Of Nodulation (AON). Rhizobia infection stimulates the production of root-derived CLE peptide hormones that are translocated to the shoot where they regulate a new signal. We used soybean to demonstrate that this shoot-derived signal is miR2111, which is transported via phloem to the root where it targets transcripts of Too Much Love (TML), a negative regulator of nodulation. Shoot perception of rhizobia-induced CLE peptides suppresses miR2111 expression, resulting in TML accumulation in roots and subsequent inhibition of nodule organogenesis. Feeding synthetic mature miR2111 via the petiole increased nodule numbers per plant. Likewise, elevating miR2111 availability by over-expression promoted nodulation, while target mimicry of TML induced the opposite effect on nodule development in wild-type plants and alleviated the supernodulating and stunted root growth phenotypes of AON-defective mutants. Additionally, in non-nodulating wild-type plants, ectopic expression of miR2111 significantly enhanced lateral root emergence with a decrease in lateral root length and average root diameter. In contrast, hairy roots constitutively expressing the target mimic construct exhibited reduced lateral root density. Overall, these findings demonstrate that miR2111 is both the critical shoot-to-root factor that positively regulates root nodule development, and also acts to shape root system architecture. This article is protected by copyright. All rights reserved.},
}
@article {pmid33384681,
year = {2020},
author = {Rodríguez, S and Correa-Galeote, D and Sánchez-Pérez, M and Ramírez, M and Isidra-Arellano, MC and Reyero-Saavedra, MDR and Zamorano-Sánchez, D and Hernández, G and Valdés-López, O and Girard, L},
title = {A Novel OmpR-Type Response Regulator Controls Multiple Stages of the Rhizobium etli - Phaseolus vulgaris N2-Fixing Symbiosis.},
journal = {Frontiers in microbiology},
volume = {11},
number = {},
pages = {615775},
pmid = {33384681},
issn = {1664-302X},
abstract = {OmpR, is one of the best characterized response regulators families, which includes transcriptional regulators with a variety of physiological roles including the control of symbiotic nitrogen fixation (SNF). The Rhizobium etli CE3 genome encodes 18 OmpR-type regulators; the function of the majority of these regulators during the SNF in common bean, remains elusive. In this work, we demonstrated that a R. etli mutant strain lacking the OmpR-type regulator RetPC57 (ΔRetPC57), formed less nodules when used as inoculum for common bean. Furthermore, we observed reduced expression level of bacterial genes involved in Nod Factors production (nodA and nodB) and of plant early-nodulation genes (NSP2, NIN, NF-YA and ENOD40), in plants inoculated with ΔRetPC57. RetPC57 also contributes to the appropriate expression of genes which products are part of the multidrug efflux pumps family (MDR). Interestingly, nodules elicited by ΔRetPC57 showed increased expression of genes relevant for Carbon/Nitrogen nodule metabolism (PEPC and GOGAT) and ΔRetPC57 bacteroids showed higher nitrogen fixation activity as well as increased expression of key genes directly involved in SNF (hfixL, fixKf, fnrN, fixN, nifA and nifH). Taken together, our data show that the previously uncharacterized regulator RetPC57 is a key player in the development of the R. etli - P. vulgaris symbiosis.},
}
@article {pmid33384333,
year = {2021},
author = {Geddes, BA and Kearsley, JVS and Huang, J and Zamani, M and Muhammed, Z and Sather, L and Panchal, AK and diCenzo, GC and Finan, TM},
title = {Minimal gene set from Sinorhizobium (Ensifer) meliloti pSymA required for efficient symbiosis with Medicago.},
journal = {Proceedings of the National Academy of Sciences of the United States of America},
volume = {118},
number = {2},
pages = {},
doi = {10.1073/pnas.2018015118},
pmid = {33384333},
issn = {1091-6490},
abstract = {Reduction of N2 gas to ammonia in legume root nodules is a key component of sustainable agricultural systems. Root nodules are the result of a symbiosis between leguminous plants and bacteria called rhizobia. Both symbiotic partners play active roles in establishing successful symbiosis and nitrogen fixation: while root nodule development is mostly controlled by the plant, the rhizobia induce nodule formation, invade, and perform N2 fixation once inside the plant cells. Many bacterial genes involved in the rhizobia-legume symbiosis are known, and there is much interest in engineering the symbiosis to include major nonlegume crops such as corn, wheat, and rice. We sought to identify and combine a minimal bacterial gene complement necessary and sufficient for symbiosis. We analyzed a model rhizobium, Sinorhizobium (Ensifer) meliloti, using a background strain in which the 1.35-Mb symbiotic megaplasmid pSymA was removed. Three regions representing 162 kb of pSymA were sufficient to recover a complete N2-fixing symbiosis with alfalfa, and a targeted assembly of this gene complement achieved high levels of symbiotic N2 fixation. The resulting gene set contained just 58 of 1,290 pSymA protein-coding genes. To generate a platform for future synthetic manipulation, the minimal symbiotic genes were reorganized into three discrete nod, nif, and fix modules. These constructs will facilitate directed studies toward expanding the symbiosis to other plant partners. They also enable forward-type approaches to identifying genetic components that may not be essential for symbiosis, but which modulate the rhizobium's competitiveness for nodulation and the effectiveness of particular rhizobia-plant symbioses.},
}
@article {pmid33374981,
year = {2020},
author = {Rubin, JA and Görres, JH},
title = {Potential for Mycorrhizae-Assisted Phytoremediation of Phosphorus for Improved Water Quality.},
journal = {International journal of environmental research and public health},
volume = {18},
number = {1},
pages = {},
doi = {10.3390/ijerph18010007},
pmid = {33374981},
issn = {1660-4601},
abstract = {During this 6th Great Extinction, freshwater quality is imperiled by upland terrestrial practices. Phosphorus, a macronutrient critical for life, can be a concerning contaminant when excessively present in waterways due to its stimulation of algal and cyanobacterial blooms, with consequences for ecosystem functioning, water use, and human and animal health. Landscape patterns from residential, industrial and agricultural practices release phosphorus at alarming rates and concentrations threaten watershed communities. In an effort to reconcile the anthropogenic effects of phosphorus pollution, several strategies are available to land managers. These include source reduction, contamination event prevention and interception. A total of 80% of terrestrial plants host mycorrhizae which facilitate increased phosphorus uptake and thus removal from soil and water. This symbiotic relationship between fungi and plants facilitates a several-fold increase in phosphorus uptake. It is surprising how little this relationship has been encouraged to mitigate phosphorus for water quality improvement. This paper explores how facilitating this symbiosis in different landscape and land-use contexts can help reduce the application of fertility amendments, prevent non-point source leaching and erosion, and intercept remineralized phosphorus before it enters surface water ecosystems. This literature survey offers promising insights into how mycorrhizae can aid ecological restoration to reconcile humans' damage to Earth's freshwater. We also identify areas where research is needed.},
}
@article {pmid33373523,
year = {2020},
author = {Fisher, JF and Mobashery, S},
title = {β-Lactams against the Fortress of the Gram-Positive Staphylococcus aureus Bacterium.},
journal = {Chemical reviews},
volume = {},
number = {},
pages = {},
doi = {10.1021/acs.chemrev.0c01010},
pmid = {33373523},
issn = {1520-6890},
abstract = {The biological diversity of the unicellular bacteria-whether assessed by shape, food, metabolism, or ecological niche-surely rivals (if not exceeds) that of the multicellular eukaryotes. The relationship between bacteria whose ecological niche is the eukaryote, and the eukaryote, is often symbiosis or stasis. Some bacteria, however, seek advantage in this relationship. One of the most successful-to the disadvantage of the eukaryote-is the small (less than 1 μm diameter) and nearly spherical Staphylococcus aureus bacterium. For decades, successful clinical control of its infection has been accomplished using β-lactam antibiotics such as the penicillins and the cephalosporins. Over these same decades S. aureus has perfected resistance mechanisms against these antibiotics, which are then countered by new generations of β-lactam structure. This review addresses the current breadth of biochemical and microbiological efforts to preserve the future of the β-lactam antibiotics through a better understanding of how S. aureus protects the enzyme targets of the β-lactams, the penicillin-binding proteins. The penicillin-binding proteins are essential enzyme catalysts for the biosynthesis of the cell wall, and understanding how this cell wall is integrated into the protective cell envelope of the bacterium may identify new antibacterials and new adjuvants that preserve the efficacy of the β-lactams.},
}
@article {pmid33372378,
year = {2020},
author = {Ishikawa, KH and Bueno, MR and Kawamoto, D and Simionato, MRL and Mayer, MPA},
title = {Lactobacilli Postbiotics reduce biofilm formation and alter transcription of virulence genes of Aggregatibacter actinomycetemcomitans.},
journal = {Molecular oral microbiology},
volume = {},
number = {},
pages = {},
doi = {10.1111/omi.12330},
pmid = {33372378},
issn = {2041-1014},
abstract = {Periodontitis is characterized by a dysbiotic microbial community and treatment strategies include the reestablishment of symbiosis by reducing pathogens abundance. Aggregatibacter actinomycetemcomitans (Aa) is frequently associated with rapidly progressing periodontitis. Since the oral ecosystem may be affected by metabolic-end-products of bacteria, we evaluated the effect of soluble compounds released by probiotic lactobacilli, known as postbiotics, on Aa biofilm and expression of virulence-associated genes. Cell-free pH-neutralized supernatants (CFS) of Lactobacillus rhamnosus Lr32, L. rhamnosus HN001, Lactobacillus acidophilus LA5 and L. acidophilus NCFM were tested against a fimbriated clinical isolate of Aa JP2-genotype (1x107 CFU/well) on biofilm formation for 24 h, and early and mature preformed biofilms (2 and 24 hours). Lactobacilli CFS partially reduced Aa viable counts and biofilms biomass, but did not affect the number of viable non-adherent bacteria, except for LA5 CFS. Furthermore, LA5 CFS and in a lesser extent HN001 CFS influenced Aa preformed biofilms. Lactobacilli postbiotics altered expression profile of Aa in a strain-specific fashion. Transcription of cytolethal distending toxin (cdtB) and leukotoxin (ltxA) was downregulated by CFS of LA5 and LR32 CFS. Although all probiotics produced detectable peroxide, transcription of katA was downregulated by lactobacilli CFS. Transcription of dspB was abrogated by LR32 and NCFM CFS, but increased by HN001, whereas expression of pgA was not affected by any postbiotic. Our data indicated the potential of postbiotics from lactobacilli, especially LA5, to reduce colonization levels of Aa to modulate the expression of virulence factors implicated in evasion of host defenses.},
}
@article {pmid33372311,
year = {2020},
author = {Xu, B and Liu, J and Zhao, C and Sun, S and Xu, J and Zhao, Y},
title = {Induction of vitamin B12 to purify biogas slurry and upgrade biogas using co-culture of microalgae and fungi.},
journal = {Water environment research : a research publication of the Water Environment Federation},
volume = {},
number = {},
pages = {},
doi = {10.1002/wer.1504},
pmid = {33372311},
issn = {1554-7531},
abstract = {Different gradient concentrations of vitamin B12 (0 ng L-1 , 10 ng L-1 , 100 ng L-1 , 1000 ng L-1) were used in the symbiosis system (Chlorella vulgaris-Ganoderma lucidum or Chlorella vulgaris-Pleurotus ostreatus) to assess their effect on simultaneous purification of biogas and removal of nutrients in biogas slurry using co-culture of microalgae and fungi. When B12 was added to the symbiosis system, biomass growth, intracellular carbonic anhydrase activity (CA), chlorophyll-a content (CHL-a), photosynthetic characteristics of the two cultivation system, and removal efficiency of nutrients in biogas slurry and CO2 in biogas were significantly higher than those in the control group. The optimal concentration of B12 was determined to be 100 ng L-1 considering the removal efficiency of nutrients and CO2 . Maximum mean chemical oxygen demand (COD), total nitrogen (TN), total phosphorus (TP) and CO2 removal efficiencies were 75.98±6.26%, 78.46±6.21%, 80.21±6.83% and 61.08 ± 5.21% in Chlorella vulgaris-Ganoderma lucidum, respectively. This study showed the potential of microalgae and fungi symbiosis system with B12 addition for nutrient removal and biogas upgrading.},
}
@article {pmid33369646,
year = {2020},
author = {Ghahremani, M and MacLean, AM},
title = {Home sweet home - how mutualistic microbes modify root development to promote symbiosis.},
journal = {Journal of experimental botany},
volume = {},
number = {},
pages = {},
doi = {10.1093/jxb/eraa607},
pmid = {33369646},
issn = {1460-2431},
abstract = {Post-embryonic organogenesis has uniquely equipped plants to become developmentally responsive to their environment, affording opportunities to remodel organism growth and architecture to an extent not possible in other higher order eukaryotes. It is this developmental plasticity that makes the field of plant-microbe interactions an exceptionally fascinating venue in which to study symbiosis. This review article describes the various ways in which mutualistic microbes alter the growth, development, and architecture of the roots of their plant hosts. We first summarize general knowledge of root development, and then examine how association of plants with beneficial microbes affects these processes. Working our way inwards from the epidermis to the pericycle, this review dissects the cell biology and molecular mechanisms underlying plant-microbe interactions in a tissue-specific manner. We examine the ways in which microbes gain entry into the root, and modify this specialized organ for symbiont accommodation, with a particular emphasis on the colonization of root cortical cells. We present significant advances in our understanding of root-microbe interactions, and conclude our discussion by identifying questions pertinent to root endosymbiosis that at present remain unresolved.},
}
@article {pmid33367261,
year = {2020},
author = {Lin, J and Frank, M and Reid, D},
title = {No Home without Hormones: How Plant Hormones Control Legume Nodule Organogenesis.},
journal = {Plant communications},
volume = {1},
number = {5},
pages = {100104},
pmid = {33367261},
issn = {2590-3462},
abstract = {The establishment of symbiotic nitrogen fixation requires the coordination of both nodule development and infection events. Despite the evolution of a variety of anatomical structures, nodule organs serve a common purpose in establishing a localized area that facilitates efficient nitrogen fixation. As in all plant developmental processes, the establishment of a new nodule organ is regulated by plant hormones. During nodule initiation, regulation of plant hormone signaling is one of the major targets of symbiotic signaling. We review the role of major developmental hormones in the initiation of the nodule organ and argue that the manipulation of plant hormones is a key requirement for engineering nitrogen fixation in non-legumes as the basis for improved food security and sustainability.},
}
@article {pmid33364583,
year = {2021},
author = {Wang, H and Zhang, H and Zhong, Z and Sun, Y and Wang, M and Chen, H and Zhou, L and Cao, L and Lian, C and Li, C},
title = {Molecular analyses of the gill symbiosis of the bathymodiolin mussel Gigantidas platifrons.},
journal = {iScience},
volume = {24},
number = {1},
pages = {101894},
pmid = {33364583},
issn = {2589-0042},
abstract = {Although the deep-sea bathymodiolin mussels have been intensively studied as a model of animal-bacteria symbiosis, it remains challenging to assess the host-symbiont interactions due to the complexity of the symbiotic tissue-the gill. Using cold-seep mussel Gigantidas platifrons as a model, we isolated the symbiont harboring bacteriocytes and profiled the transcriptomes of the three major parts of the symbiosis-the gill, the bacteriocyte, and the symbiont. This breakdown of the complex symbiotic tissue allowed us to characterize the host-symbiont interactions further. Our data showed that the gill's non-symbiotic parts play crucial roles in maintaining and protecting the symbiosis; the bacteriocytes supply the symbiont with metabolites, control symbiont population, and shelter the symbiont from phage infection; the symbiont dedicates to the methane oxidation and energy production. This study demonstrates that the bathymodiolin symbiosis interacts at the tissue, cellular, and molecular level, maintaining high efficiency and harmonic chemosynthetic micro niche.},
}
@article {pmid33361654,
year = {2020},
author = {Goto, Y},
title = {[Commensal bacteria prevent pathogenic bacterial infection by inducing of activation of host immune system].},
journal = {Nihon saikingaku zasshi. Japanese journal of bacteriology},
volume = {75},
number = {2},
pages = {185-194},
doi = {10.3412/jsb.75.185},
pmid = {33361654},
issn = {1882-4110},
abstract = {Countless numbers of bacteria inhabit the intestinal tract. One of the important functions of gut microbiota is the "colonization resistance" against infection by pathogenic microorganisms. However, detailed mechanism of the colonization resistance of intestinal bacteria is still largely unknown. We tried to identify molecular and cellular mechanism of it and found that antigen presentation by dendritic cells is required for the induction of intestinal segmented filamentous bacteria (SFB)-induced T helper 17 (Th17) cells that contribute to the protection against infection by Citrobacter rodentium. We further identified that gut Th17 cells selectively recognize antigens derived from SFB. We also revealed that SFB induce α1,2-fucose, one of carbohydrate chains, expressed on the intestinal epithelial cells mediated by group 3 innate lymphoid cells. Epithelial α1,2-fucose protected against infection by pathogenic bacterium Salmonella typhimurium. Furthermore, it was found that intestinal bacteria inhibit colonization of the pathogenic fungus Candida albicans as well as pathogenic bacteria. From these studies, detailed mechanism of "colonization resistance" against pathogenic microorganisms by intestinal bacteria has been clarified.},
}
@article {pmid33361196,
year = {2020},
author = {Leo, V and Tran, E and Morona, R},
title = {Polysaccharide co-polymerase WzzB/WzzE chimeras reveal transmembrane 2 region of WzzB is important for interaction with WzyB.},
journal = {Journal of bacteriology},
volume = {},
number = {},
pages = {},
doi = {10.1128/JB.00598-20},
pmid = {33361196},
issn = {1098-5530},
abstract = {The ability of bacteria to synthesise complex polysaccharide chains at a controlled number of repeating units has wide implications for a range of biological activities that include: symbiosis, biofilm formation and immune system avoidance. Complex polysaccharide chains such as the O antigen (Oag) component of lipopolysaccharide and the enterobacterial common antigen (ECA) are synthesised by the most common polysaccharide synthesis pathway used in bacteria, known as the Wzy-dependent pathway. The Oag and ECA are polymerized into chains via the inner membrane proteins WzyB and WzyE, respectively, while the respective co-polymerases WzzB and WzzE modulate the number of repeat units in the chains or "the modal length" of the polysaccharide via a hypothesised interaction. Our data shows for the first time "cross-talk" between Oag and ECA synthesis in that WzzE is able to partially regulate Oag modal length via a potential interaction with WzyB. To investigate this, one or both of the transmembrane regions (TM1 and TM2) of WzzE and WzzB were swapped creating six chimera proteins. Several chimeric proteins showed significant increases Oag modal length control, while others reduced control. Additionally, co-purification experiments show an interaction between WzyB and WzzB for the first time without the use of a chemical cross-linker, and a novel interaction between WzyB and WzzE. These results suggest the TM2 region of Wzz proteins plays a critical role in Oag and ECA modal length control, presumably via the interaction with respective Wzy proteins, thus providing insight into the complex mechanism underlying the control of polysaccharide biosynthesis.ImportanceBacteria synthesise complex polysaccharide chains at a controlled number of repeating units, this has wide implications for a range of bacterial activities involved in virulence. Examples of complex polysaccharide chains include, the O antigen (Oag) component of lipopolysaccharide and the enterobacterial common antigen (ECA), both of these examples are predominantly synthesised by their own independent Wzy-dependent pathway. Our data show for the first time "cross-talk" between Oag and ECA synthesis and identifies novel physical protein-protein interactions between proteins in these systems. These findings further the understanding of how the system functions to control polysaccharide chain length which has great implications for novel biotechnologies and/or the combat of bacterial diseases.},
}
@article {pmid33360287,
year = {2020},
author = {Ghorbani, A and Tafteh, M and Roudbari, N and Pishkar, L and Zhang, W and Wu, C},
title = {Piriformospora indica augments arsenic tolerance in rice (Oryza sativa) by immobilizing arsenic in roots and improving iron translocation to shoots.},
journal = {Ecotoxicology and environmental safety},
volume = {209},
number = {},
pages = {111793},
doi = {10.1016/j.ecoenv.2020.111793},
pmid = {33360287},
issn = {1090-2414},
abstract = {Arsenic (As) toxicity can be a hazardous threat to sustainable agriculture and human health. Piriformospora indica (P. indica), as a beneficial endophytic fungus, is involved in the plant tolerance to stressful conditions. Here, the biochemical and molecular responses of rice plants to As (50 μM) phytotoxicity and P. indica inoculation as well as the role of P. indica in improving rice adaptation to As stress were evaluated. The results showed that As stress reduced chlorophylls content, chlorophyll fluorescence yield (Fv/Fm), electron transport rate (ETR) and growth. However, P. indica restored chlorophyll content and growth. P. indica decreased the contents of methylglyoxal and malondialdehyde by improving the activity of enzymes involved in the glyoxalase pathway and modulating the redox state of the ascorbic acid-glutathione cycle, and consequently, increased the plant tolerance to As toxicity. P. indica, by downregulating Lsi2 expression (involved in As translocation to the shoot) and upregulating PCS1 and PCS2 expression (involved in As sequestration in vacuoles), immobilized As in the roots and reduced damage to photosynthetic organs. P. indica increased iron (Fe) accumulation in the shoot under As toxicity by upregulating the expression of IRO2, YSL2 and FRDL1 genes. The results of the present study augmented our knowledge in using P. indica symbiosis in improving the tolerance of rice plants against As toxicity for sustainable agriculture.},
}
@article {pmid33359013,
year = {2020},
author = {He, C and Gao, H and Wang, H and Guo, Y and He, M and Peng, Y and Wang, X},
title = {GSK3-Mediated Stress Signaling Inhibits Legume-Rhizobium Symbiosis by Phosphorylating GmNSP1 in Soybean.},
journal = {Molecular plant},
volume = {},
number = {},
pages = {},
doi = {10.1016/j.molp.2020.12.015},
pmid = {33359013},
issn = {1752-9867},
abstract = {Legumes establish symbiotic associations with rhizobia for biological nitrogen fixation. This process is highly regulated by various abiotic stresses, but the underlying genetic and molecular mechanisms are largely unknown. Here, we established that the glycogen synthase kinase 3 (GSK3)-like kinase, GmSK2-8, plays an important role in inhibiting symbiotic signaling and nodule formation in soybean (Glycine max) under salt stress. GmSK2-8 was strongly induced in soybean under high-salt conditions. GmSK2-8 interacted with two members of Glycine max Nodulation Signaling Pathway 1 (GmNSP1), GmNSP1a and GmNSP1b; these key transcription factors are essential for rhizobial infection, nodule initiation, and symbiotic gene expression in soybean. Furthermore, GmSK2-8 phosphorylated the LHRI domain of GmNSP1a, inhibiting its binding to the promoters of symbiotic genes, which reduces nodule formation under salt stress. Knockdown of GmSK2-8 and its close homologs reduced sensitivity to salt stress during nodule formation. Therefore, GSK3-like kinases directly regulate GmNSP1 and thereby mediate salt-inhibited legume-rhizobium symbiosis. These findings provide novel targets for improving symbiotic nitrogen fixation under environmental stress conditions in soybean and possibly other legumes.},
}
@article {pmid33356903,
year = {2020},
author = {Pérez-Rodríguez, F and González-Prieto, JM and Vera-Núñez, JA and Ruiz-Medrano, R and Peña-Cabriales, JJ and Ruiz-Herrera, J},
title = {Wide distribution of the Ustilago maydis-bacterium endosymbiosis in naturally infected maize plants.},
journal = {Plant signaling & behavior},
volume = {},
number = {},
pages = {1855016},
doi = {10.1080/15592324.2020.1855016},
pmid = {33356903},
issn = {1559-2324},
abstract = {We have previously described that laboratory strains of Ustilago maydis, a fungal pathogen of maize and its ancestor teosinte, harbor an intracellular bacterium that enables the fungus to fix nitrogen. However, it is not clear whether other strains isolated from nature also harbor endosymbiotic bacteria, and whether these fix nitrogen for its host. In the present study, we isolated U. maydis strains from naturally infected maize. All the isolated strains harbored intracellular bacteria as determined by PCR amplification of the 16S rRNA gene, and some of them showed capacity to fix nitrogen. That these are truly bacterial endosymbionts were shown by the fact that, after thorough treatments with CuSO4 followed by serial incubations with antibiotics, the aforementioned bacterial gene was still amplified in treated fungi. In all, these data support the notion that U. maydis-bacterium endosymbiosis is a general phenomenon in this species.},
}
@article {pmid33355157,
year = {2020},
author = {Hill, Y and Colombi, E and Bonello, E and Haskett, T and Ramsay, J and O'Hara, G and Terpolilli, J},
title = {Evolution of diverse effective N2-fixing microsymbionts of Cicer arietinum following horizontal transfer of the Mesorhizobium ciceri CC1192 symbiosis integrative and conjugative element.},
journal = {Applied and environmental microbiology},
volume = {},
number = {},
pages = {},
doi = {10.1128/AEM.02558-20},
pmid = {33355157},
issn = {1098-5336},
abstract = {Rhizobia are soil bacteria capable of forming N2-fixing symbioses with legumes, with highly effective strains often selected in agriculture as inoculants to maximize symbiotic N2 fixation. When rhizobia in the genus Mesorhizobium have been introduced with exotic legumes into farming systems, horizontal transfer of symbiosis Integrative and Conjugative Elements (ICEs) from the inoculant strain to soil bacteria has resulted in the evolution of ineffective N2-fixing rhizobia that are competitive for nodulation with the target legume. In Australia, Cicer arietinum (chickpea) has been inoculated since the 1970's with Mesorhizobium ciceri sv. ciceri CC1192, a highly effective strain from Israel. Although the full genome sequence of this organism is available, little is known about the mobility of its symbiosis genes and the diversity of cultivated C. arietinum-nodulating organisms. Here, we show the CC1192 genome harbors a 419-kb symbiosis ICE (ICEMcSym1192) and a 648-kb repABC-type plasmid pMC1192 carrying putative fix genes. We sequenced the genomes of 11 C. arietinum nodule isolates from a field site exclusively inoculated with CC1192 and showed they were diverse unrelated Mesorhizobium carrying ICEMcSym1192, indicating they had acquired the ICE by environmental transfer. No exconjugants harboured pMc1192 and the plasmid was not essential for N2 fixation in CC1192. Laboratory conjugation experiments confirmed ICEMcSym1192 is mobile, integrating site-specifically within the 3' end of one of the four ser-tRNA genes in the R7ANS recipient genome. Strikingly, all ICEMcSym1192 exconjugants were as efficient at fixing N2 with C. arietinum as CC1192, demonstrating ICE transfer does not necessarily yield ineffective microsymbionts as previously observed.Importance Symbiotic N2 fixation is a key component of sustainable agriculture and in many parts of the world legumes are inoculated with highly efficient strains of rhizobia to maximise fixed N2 inputs into farming systems. Symbiosis genes for Mesorhizobium spp. are often encoded chromosomally within mobile gene clusters called Integrative and Conjugative Elements or ICEs. In Australia, where all agricultural legumes and their rhizobia are exotic, horizontal transfer of ICEs from inoculant Mesorhizobium strains to native rhizobia has led to the evolution of inefficient strains that outcompete the original inoculant, with the potential to render it ineffective. However, the commercial inoculant strain for Cicer arietinum (chickpea), M. ciceri CC1192, has a mobile symbiosis ICE (ICEMcSym1192) which can support high rates of N2 fixation following either environmental or laboratory transfer into diverse Mesorhizobium backgrounds, demonstrating ICE transfer does not necessarily yield ineffective microsymbionts as previously observed.},
}
@article {pmid33355113,
year = {2020},
author = {Ebert, KM and Arnold, WG and Ebert, PR and Merritt, DJ},
title = {Hindgut microbiota reflects different digestive strategies in dung beetles (Coleoptera: Scarabaeidae: Scarabaeinae).},
journal = {Applied and environmental microbiology},
volume = {},
number = {},
pages = {},
doi = {10.1128/AEM.02100-20},
pmid = {33355113},
issn = {1098-5336},
abstract = {Gut microbes play an important role in the biology and evolution of insects. Australian native dung beetles (Scarabaeinae) present an opportunity to study gut microbiota in an evolutionary context as they come from two distinct phylogenetic lineages and some species in each lineage have secondarily adapted to alternative or broader diets. In this study, we characterised the hindgut bacterial communities found in 21 species of dung beetles across two lineages using 16S rRNA sequencing. We found that gut microbial diversity was more dependent on host phylogeny and gut morphology than specific dietary preferences or environment. In particular, gut microbial diversity was highest in the endemic, flightless genus Cephalodesmius that feeds on a broad range of composted organic matter. The hindgut of Cephalodesmius harbours a highly conserved core set of bacteria suggesting that the bacteria are symbiotic. Symbiosis is supported by the persistence of the core microbiota across isolated beetle populations and between species in the genus. A co-evolutionary relationship is supported by the expansion of the hindgut to form a fermentation chamber and the fermentative nature of the core microbes. In contrast, Australian species of the widespread dung beetle genus Onthophagus, specialise on a single food resource such as dung or fungus, exhibit minimal food processing behaviour, have a short, narrow hindgut and a variable gut microbiota with relatively few core bacterial taxa. A conserved, complex gut microbiota is hypothesised to be unnecessary for this highly mobile genus.IMPORTANCE Dung beetles are a very important part of an ecosystem because of their role in the removal and decomposition of vertebrate dung. It has been suspected that symbiotic gut bacteria facilitate this role, a hypothesis that we have explored with high throughput barcoding. We found that differences in hindgut morphology had the greatest effect on the bacterial community composition. Species with a hindgut fermentation chamber harboured a distinctly different hindgut community compared to those species with a narrow, undifferentiated hindgut. Diet and phylogeny were also associated with differences in gut community. Further understanding of the relationships between dung beetles and their gut microbes will provide insights into the evolution of their behaviours and how gut communities contribute to their fitness.},
}
@article {pmid33355107,
year = {2020},
author = {Petersen, JM and Yuen, B},
title = {The symbiotic 'all-rounders': Partnerships between marine animals and chemosynthetic nitrogen-fixing bacteria.},
journal = {Applied and environmental microbiology},
volume = {},
number = {},
pages = {},
doi = {10.1128/AEM.02129-20},
pmid = {33355107},
issn = {1098-5336},
abstract = {Nitrogen fixation is a widespread metabolic trait in certain types of microorganisms called diazotrophs. Bioavailable nitrogen is limited in various habitats on land and in the sea, and accordingly, a range of plant, animal, and single-celled eukaryotes have evolved symbioses with diverse diazotrophic bacteria, with enormous economic and ecological benefits. Until recently, all known nitrogen-fixing symbionts were heterotrophs such as nodulating rhizobia, or photoautotrophs such as cyanobacteria. In 2016, the first chemoautotrophic nitrogen-fixing symbionts were discovered in a common family of marine clams, the Lucinidae. Chemosynthetic nitrogen-fixing symbionts use the chemical energy stored in reduced sulfur compounds to power carbon and nitrogen fixation, making them metabolic 'all-rounders' with multiple functions in the symbiosis. This distinguishes them from heterotrophic symbionts that require a source of carbon from their host, and their chemosynthetic metabolism distinguishes them from photoautotrophic symbionts that produce oxygen, a potent inhibitor of nitrogenase. In this review, we consider evolutionary aspects of this discovery, by comparing strategies that have evolved for hosting intracellular nitrogen-fixing symbionts in plants and animals. The symbiosis between lucinid clams and chemosynthetic nitrogen-fixing bacteria also has important ecological impacts, as they form a nested symbiosis with endangered marine seagrasses. Notably, nitrogen fixation by lucinid symbionts may help support seagrass health by providing a source of nitrogen in seagrass habitats. These discoveries were enabled by new techniques for understanding the activity of microbial populations in natural environments. However, an animal (or plant) host represents a diverse landscape of microbial niches due to its structural, chemical, immune and behavioural properties. In future, methods that resolve microbial activity at the single cell level will provide radical new insights into the regulation of nitrogen fixation in chemosynthetic symbionts, shedding new light on the evolution of nitrogen-fixing symbioses in contrasting hosts and environments.},
}
@article {pmid33353519,
year = {2020},
author = {Rose, A and Titus, BM and Romain, J and Vondriska, C and Exton, DA},
title = {Multiple cleaner species provide simultaneous services to coral reef fish clients.},
journal = {Biology letters},
volume = {16},
number = {12},
pages = {20200723},
doi = {10.1098/rsbl.2020.0723},
pmid = {33353519},
issn = {1744-957X},
abstract = {Cleaning symbioses on tropical coral reefs are typically documented between two species: a single client fish and one or more conspecific cleaners. However, multiple cleaner species living sympatrically in the Caribbean have been anecdotally reported to simultaneously clean the same client. Nothing is known about the patterns and processes driving these interactions, which may differ from those involving a single cleaner species. Here, we used remote underwater videography on three reefs in Honduras to record simultaneous cleaning interactions involving Pederson's cleaner shrimp (Ancylomenes pedersoni) and cleaner gobies (Elacatinus spp.). A pilot study on adjacent shrimp and goby stations found interactions were always initiated by shrimp. A larger, multi-year dataset shows cleaner gobies joined 28% of all interactions initiated at A. pedersoni cleaning stations with cleaner gobies residing nearby. Client body size significantly predicted simultaneous cleaning interactions, with 45% of interactions simultaneous for clients greater than 20 cm total body length compared with only 8% for clients less than 20 cm. We also found that simultaneous cleaning interactions lasted over twice as long as shrimp-only interactions. We propose these novel multi-species interactions to be an ideal model system to explore broader questions about coexistence, niche overlap and functional redundancy among sympatric cleaner species.},
}
@article {pmid33353248,
year = {2020},
author = {Patel, CI and Labana, D and Pandya, S and Modi, K and Ghayvat, H and Awais, M},
title = {Histogram of Oriented Gradient-Based Fusion of Features for Human Action Recognition in Action Video Sequences.},
journal = {Sensors (Basel, Switzerland)},
volume = {20},
number = {24},
pages = {},
pmid = {33353248},
issn = {1424-8220},
abstract = {Human Action Recognition (HAR) is the classification of an action performed by a human. The goal of this study was to recognize human actions in action video sequences. We present a novel feature descriptor for HAR that involves multiple features and combining them using fusion technique. The major focus of the feature descriptor is to exploits the action dissimilarities. The key contribution of the proposed approach is to built robust features descriptor that can work for underlying video sequences and various classification models. To achieve the objective of the proposed work, HAR has been performed in the following manner. First, moving object detection and segmentation are performed from the background. The features are calculated using the histogram of oriented gradient (HOG) from a segmented moving object. To reduce the feature descriptor size, we take an averaging of the HOG features across non-overlapping video frames. For the frequency domain information we have calculated regional features from the Fourier hog. Moreover, we have also included the velocity and displacement of moving object. Finally, we use fusion technique to combine these features in the proposed work. After a feature descriptor is prepared, it is provided to the classifier. Here, we have used well-known classifiers such as artificial neural networks (ANNs), support vector machine (SVM), multiple kernel learning (MKL), Meta-cognitive Neural Network (McNN), and the late fusion methods. The main objective of the proposed approach is to prepare a robust feature descriptor and to show the diversity of our feature descriptor. Though we are using five different classifiers, our feature descriptor performs relatively well across the various classifiers. The proposed approach is performed and compared with the state-of-the-art methods for action recognition on two publicly available benchmark datasets (KTH and Weizmann) and for cross-validation on the UCF11 dataset, HMDB51 dataset, and UCF101 dataset. Results of the control experiments, such as a change in the SVM classifier and the effects of the second hidden layer in ANN, are also reported. The results demonstrate that the proposed method performs reasonably compared with the majority of existing state-of-the-art methods, including the convolutional neural network-based feature extractors.},
}
@article {pmid33352781,
year = {2020},
author = {Khoshkhatti, N and Eini, O and Koolivand, D and Pogiatzis, A and Klironomos, JN and Pakpour, S},
title = {Differential Response of Mycorrhizal Plants to Tomato bushy stunt virus and Tomato mosaic virus Infection.},
journal = {Microorganisms},
volume = {8},
number = {12},
pages = {},
pmid = {33352781},
issn = {2076-2607},
abstract = {Tomato bushy stunt virus (TBSV) and Tomato mosaic virus (ToMV) are important economic pathogens in tomato fields. Rhizoglomus irregulare is a species of arbuscular mycorrhizal (AM) fungus that provides nutrients to host plants. To understand the effect of R. irregulare on the infection by TBSV/ToMV in tomato plants, in a completely randomized design, five treatments, including uninfected control plants without AM fungi (C), uninfected control plants with AM fungi (M) TBSV/ToMV-infected plants without AM fungi (V), TBSV/ToMV-infected plants before mycorrhiza (VM) inoculation, and inoculated plants with mycorrhiza before TBSV/ToMV infection (MV), were studied. Factors including viral RNA accumulation and expression of Pathogenesis Related proteins (PR) coding genes including PR1, PR2, and PR3 in the young leaves were measured. For TBSV, a lower level of virus accumulation and a higher expression of PR genes in MV plants were observed compared to V and VM plants. In contrast, for ToMV, a higher level of virus accumulation and a lower expression of PR genes in MV plants were observed as compared to V and VM plants. These results indicated that mycorrhizal symbiosis reduces or increases the viral accumulation possibly via the regulation of PR genes in tomato plants.},
}
@article {pmid33351723,
year = {2020},
author = {Joshi, M and Kulkarni, M},
title = {Evaluation and Planning for a 250 Bedded COVID-19 Healthcare Infrastructure in City of Gurgaon, India.},
journal = {Hospital topics},
volume = {},
number = {},
pages = {1-9},
doi = {10.1080/00185868.2020.1859343},
pmid = {33351723},
issn = {1939-9278},
abstract = {The novel corona virus has reached the pandemic levels since March 2020. This has exerted tremendous pressure on existing infrastructure. Amenities related to quarantine and isolation are new norms in healthcare set-ups all over the world. The present study helps to understand the guidelines needed to change the current available infrastructural resources of essential departments in addition to forecasting and organizing the infrastructure required to cater the special needs of the COVID-19 patients without compromising the smooth functioning of the healthcare facility and not risking the safety of the health care professionals delivering it.},
}
@article {pmid33351288,
year = {2020},
author = {Abdel-Gaber, R and Alajmi, R and Haddadi, R and El-Ashram, S},
title = {The phylogenetic position of Arhaphe deviatica within Hemipteran insects: A potential model species for eco-devo studies of symbiosis.},
journal = {Journal of experimental zoology. Part B, Molecular and developmental evolution},
volume = {},
number = {},
pages = {},
doi = {10.1002/jez.b.23019},
pmid = {33351288},
issn = {1552-5015},
abstract = {Insecta is known to be the most diverse group of species, exhibiting numerous forms of endosymbiotic associations. Molecular techniques have provided significant indicators for insect-microbe interactions. The present study aimed to register one of the true bugs of pentatomomorpha and clarify its taxonomic position through phylogenetic analysis of the partial 16S rRNA gene region. A maximum likelihood analysis retrieved a generally well-supported phylogeny based on Tamura 3-parameter model. Based on the partial mitochondrial 16S rRNA gene sequences, a phylogenetic study of suborder Heteroptera relationships within Hemipteras' order was constructed. Sequences of 221 bases of the 3' end of the gene from 28 species within 16 families were analyzed. This analysis and bootstrap confidence revealed two major clades comprising four suborders within Hemiptera, with a close relationship between Heteroptera + (Sternorrhyncha + (Auchenorrhycha + Coleorrhyncha)). Infraorder Pentatomomorpha is forming a sister group with a substantial bootstrap value to Cimicomorpha. Pyrrhocoroidea forms a sister relationship with Lygaeoidea + Coreoidea. There is a close relationship between Largidae and Pyrrhocoridae within Pyrrhocoroidea. The results show that the present species is firmly embedded in the genus Arhaphe with 94.35% sequence resemblance to its congeners. Besides, the recovered hemipteran species considered a potential model group for studying different symbionts. We propose both phylogenetic and ecological evolutionary developmental biology viewpoints for a more synthetic understanding of insect populations' molecular evolution.},
}
@article {pmid33348186,
year = {2020},
author = {Fan, YV and Varbanov, PS and Klemeš, JJ and Romanenko, SV},
title = {Urban and industrial symbiosis for circular economy: Total EcoSite Integration.},
journal = {Journal of environmental management},
volume = {279},
number = {},
pages = {111829},
doi = {10.1016/j.jenvman.2020.111829},
pmid = {33348186},
issn = {1095-8630},
abstract = {The paper presents an extension of Pinch Analysis and namely, Total Site Process Integration. It benefits from up to date developments and introduction of Total EcoSite Integration for urban and industrial symbiosis. An important development is Pinch Analysis for Solid Waste Integration which is a crucial step for the symbiosis in a circular economy. As the potential EcoSites are usually extensive and cover various units, a methodology based on clusters has been used. The solution has been supported by graphical tools using the analogy with already implemented extensions of Pinch Analysis. The results of a demonstration case study revealed the potential of the novel approach. The identified integrated design increased the energy recovered from the solid waste by 11.39 MWh/d and diverted 2 t/d of the waste from the landfill, benefiting both the urban and industrial site. The proposed approach is also capable of minimising the requirement of energy-intensive thermal drying for waste whenever the process allowed, subsequently offer a solution with lower environmental footprint and cost. For future work, a even more comprehensive case study can be conducted by considering the other forms of the waste, recovery process and drying approaches.},
}
@article {pmid33347631,
year = {2020},
author = {Tiwari, M and Pandey, V and Singh, B and Bhatia, S},
title = {Dynamics of miRNA mediated regulation of legume symbiosis.},
journal = {Plant, cell & environment},
volume = {},
number = {},
pages = {},
doi = {10.1111/pce.13983},
pmid = {33347631},
issn = {1365-3040},
abstract = {Symbiotic nitrogen fixation in legume nodules is important in soils with low nitrogen availability. The initiation and sustainability of symbiosis requires cellular reprogramming that involves the miRNA-mediated inhibition or activation of specific nodulation genes. The high-throughput sequencing of small RNA libraries has identified miRNAs and their targets, which are the major players in the post-transcriptional gene regulation (PTGS) of the different stages of legume-rhizobia symbiosis ranging from bacterial colonization and organogenesis to symbiotic nitrogen fixation. Here we present an overview of information obtained from the miRNA libraries from nodulating tissues that have been sequenced to date. The functional analysis of miRNAs has revealed roles in phytohormone homeostasis and spatio-temporal regulation, as well as the mobility of miRNAs and their functions in shoot to root signalling that affects diverse functions, including bacterial entry, meristem division and differentiation, nitrogen fixation and senescence. Furthermore, small RNA fragments of rhizobial origin repress complementary plant mRNAs. We also consider the roles of miRNAs in determinate or indeterminate nodules. Taken together, this overview confirms that miRNAs are master regulators of the legume-rhizobia symbiosis. This article is protected by copyright. All rights reserved.},
}
@article {pmid33345523,
year = {2020},
author = {Li, JJ and Zeng, M},
title = {[Ecological significance of arbuscular mycorrhiza on plant rhizosphere stress].},
journal = {Ying yong sheng tai xue bao = The journal of applied ecology},
volume = {31},
number = {9},
pages = {3216-3226},
doi = {10.13287/j.1001-9332.202009.039},
pmid = {33345523},
issn = {1001-9332},
mesh = {*Mycorrhizae ; Plant Roots ; Plants ; Rhizosphere ; Symbiosis ; },
abstract = {In recent years, Chinese scientists have made remarkable achievements in on mycorrhizal molecular biology, nutrition, taxonomy, and ecology, with arbuscular mycorrhizal fungus (AMF) having been mostly studied. AMF can form symbiotic relationship with roots of most terrestrial plants, promote plant growth and development, improve plant stress resistance, maintain ecological balance, and protect ecological environment. This review mainly introduced the ecological function and mechanism of AMF in plant rhizosphere stress from the aspects of abiotic (drought stress, heavy metal pollution, saline-alkali stress) and biotic stresses (pathogenic bacteria and nematode infection). We proposed the remaining deficiencies and research prospects in this field to provide refe-rence for future research of AMF.},
}
@article {pmid33338554,
year = {2020},
author = {Ferrer, B and Prince, LM and Tinkov, AA and Santamaria, A and Farina, M and Rocha, JB and Bowman, AB and Aschner, M},
title = {Chronic exposure to methylmercury enhances the anorexigenic effects of leptin in C57BL/6J male mice.},
journal = {Food and chemical toxicology : an international journal published for the British Industrial Biological Research Association},
volume = {147},
number = {},
pages = {111924},
doi = {10.1016/j.fct.2020.111924},
pmid = {33338554},
issn = {1873-6351},
abstract = {Several studies have demonstrated that heavy metals disrupt energy homeostasis. Leptin inhibits food intake and decreases body weight through activation of its receptor in the hypothalamus. The impact of heavy metals on leptin signaling in the hypothalamus is unclear. Here, we show that the environmental pollutant, methylmercury (MeHg), favors an anorexigenic profile in wild-type males. C57BL/6J mice were exposed to MeHg via drinking water (5 ppm) up to 30 days. Our data shows that MeHg exposure was associated with changes in leptin induced activation of Janus kinase 2 (JAK2)/signal transducer and activator of transcription 3 (STAT3) signaling pathway in the hypothalamus. In males, the activation of JAK2/STAT3 signaling pathway was sustained by an increase in SOCS3 protein levels. In females, MeHg-activated STAT3 was inhibited by a concomitant increase in PTP1B. Taken together, our data suggest that MeHg enhanced leptin effects in males, favoring an anorexigenic profile in males, which notably, have been shown to be more sensitive to the neurological effects of this organometal than females. A better understanding of MeHg-induced molecular mechanism alterations in the hypothalamus advances the understanding of its neurotoxicity and provides molecular sites for novel therapies.},
}
@article {pmid33337985,
year = {2020},
author = {Mei, Y and Liu, CY and Li, SH and Guerin-Laguette, A and Xiao, YJ and Tang, P and Wan, SP and Bonito, G and Wang, Y},
title = {Phlebopus roseus, a new edible bolete from China, is associated with insects and plants.},
journal = {Mycologia},
volume = {},
number = {},
pages = {1-10},
doi = {10.1080/00275514.2020.1816781},
pmid = {33337985},
issn = {1557-2536},
abstract = {Phlebopus roseus is described as new based on collections from southwest China. Phylogenetic analyses of nuclear rDNA internal transcribed spacer region ITS1-5.8S-ITS2 (ITS) and portions of nuclear 28S rDNA (28S), translation elongation factor 1-alpha (tef1), and the largest and second largest subunits of RNA polymerase II (rpb1, rpb2) support P. roseus as a novel species in the genus Phlebopus (Boletinellaceae, Boletales). The new species resembles P. portentosus but differs from it in that mature basidiomata have a bright rose-red-colored stipe and a radiate tubular hymenophore with nested pores. Despite extensive searching, P. roseus has only been found at four sites within a 24-hectare orchard dominated by Eriobotrya japonica, which is agriculturally important given its fruit production (loquats). Therefore, this species appears to be endemic and geographically restricted. The ecology of this bolete is also unique. In line with the trophic behavior of other species in the Boletinellaceae, our observations indicate that P. roseus forms a symbiotic association with the scale insect Coccus hesperidum, identified through sequence analysis of its mitochondrial cytochrome c oxidase subunit I (COI) region, to form fungus-insect galls that develop on roots of E. japonica trees. Phlebopus roseus is an edible mushroom species and is collected from the type location by farmers and sold commercially in limited quantities at local markets alongside P. portentosus and other fungi.},
}
@article {pmid33332711,
year = {2020},
author = {Sgard, C and Bier, JC and Peigneux, P},
title = {Gesturing helps memory encoding in aMCI.},
journal = {Journal of neuropsychology},
volume = {},
number = {},
pages = {},
doi = {10.1111/jnp.12238},
pmid = {33332711},
issn = {1748-6653},
abstract = {Encoding in episodic memory is a step often impaired in patients with amnestic Mild Cognitive Impairment (aMCI). However, procedural memory processes are still relatively preserved. In line with previous research on the enactment effect, we investigated the potential benefit of encoding words combined with imitative gestures on episodic memory. Based on the Grober and Buschke's free/cued recall procedure, we developed the Symbiosis test in which 13 patients with aMCI and 16 healthy elderly participants learned 32 words belonging to 16 different semantic categories either in a verbal encoding (A) or a bimodal (B; verbal and motor imitation) condition, using a blocked ABBA/BAAB procedure. Overall, memory retrieval was better in healthy participants than in patients with aMCI, and better for cued retrieval in the bimodal encoding (gesture cues) than the verbal encoding (category cues) condition, but there was no interaction effect between group and encoding conditions. These results show that performing concomitant gestures can enhance cued episodic memory retrieval in patients with aMCI and in healthy elderly controls. The Symbiosis test broadens the scope of the enactment effect, from action phrases to isolated words learning in patients with aMCI. Future work should investigate how bimodal encoding provides novel perspectives for memory rehabilitation in patients with aMCI.},
}
@article {pmid33332645,
year = {2020},
author = {Eichmann, R and Richards, L and Schäfer, P},
title = {Hormones as go-betweens in plant microbiome assembly.},
journal = {The Plant journal : for cell and molecular biology},
volume = {},
number = {},
pages = {},
doi = {10.1111/tpj.15135},
pmid = {33332645},
issn = {1365-313X},
abstract = {The interaction of plants with complex microbial communities is the result of co-evolution over millions of years and contributed to plant transition and adaptation to land. The ability of plants to be an essential part of complex and highly dynamic ecosystems is dependent on their interaction with diverse microbial communities. Plant microbiota can support, and even enable, the diverse functions of plants and are crucial in sustaining plant fitness under often rapidly changing environments. The composition and diversity of microbiota differs between plant and soil compartments. It indicates that microbial communities in these compartments are not static but are adjusted by the environment as well as inter-microbial and plant-microbe communication. Hormones take a crucial role in contributing to the assembly of plant microbiomes, and plants and microbes often employ the same hormones with completely different intentions. Here, the function of hormones as go-betweens between plants and microbes to influence the shape of plant microbial communities is discussed. The versatility of plant and microbe-derived hormones essentially contributes to the creation of habitats that are the origin of diversity and, thus, multi-functionality of plants, their microbiota and ultimately ecosystems.},
}
@article {pmid33329684,
year = {2020},
author = {Sawa, S and Sato, MH and Favery, B},
title = {Editorial: Developmental Modification Under Biotic Interactions in Plants.},
journal = {Frontiers in plant science},
volume = {11},
number = {},
pages = {619804},
pmid = {33329684},
issn = {1664-462X},
}
@article {pmid33329665,
year = {2020},
author = {Villar, I and Larrainzar, E and Milazzo, L and Pérez-Rontomé, C and Rubio, MC and Smulevich, G and Martínez, JI and Wilson, MT and Reeder, B and Huertas, R and Abbruzzetti, S and Udvardi, M and Becana, M},
title = {A Plant Gene Encoding One-Heme and Two-Heme Hemoglobins With Extreme Reactivities Toward Diatomic Gases and Nitrite.},
journal = {Frontiers in plant science},
volume = {11},
number = {},
pages = {600336},
pmid = {33329665},
issn = {1664-462X},
abstract = {In plants, symbiotic hemoglobins act as carriers and buffers of O2 in nodules, whereas nonsymbiotic hemoglobins or phytoglobins (Glbs) are ubiquitous in tissues and may perform multiple, but still poorly defined, functions related to O2 and/or nitric oxide (NO). Here, we have identified a Glb gene of the model legume Medicago truncatula with unique properties. The gene, designated MtGlb1-2, generates four alternative splice forms encoding Glbs with one or two heme domains and 215-351 amino acid residues. This is more than double the size of any hemoglobin from plants or other organisms described so far. A combination of molecular, cellular, biochemical, and biophysical methods was used to characterize these novel proteins. RNA-sequencing showed that the four splice variants are expressed in plant tissues. MtGlb1-2 is transcriptionally activated by hypoxia and its expression is further enhanced by an NO source. The gene is preferentially expressed in the meristems and vascular bundles of roots and nodules. Two of the proteins, bearing one or two hemes, were characterized using mutants in the distal histidines of the hemes. The Glbs are extremely reactive toward the physiological ligands O2, NO, and nitrite. They show very high O2 affinities, NO dioxygenase activity (in the presence of O2), and nitrite reductase (NiR) activity (in the absence of O2) compared with the hemoglobins from vertebrates and other plants. We propose that these Glbs act as either NO scavengers or NO producers depending on the O2 tension in the plant tissue, being involved in the fast and fine tuning of NO concentration in the cytosol in response to sudden changes in O2 availability.},
}
@article {pmid33329491,
year = {2020},
author = {Moreno-Ruiz, D and Lichius, A and Turrà, D and Di Pietro, A and Zeilinger, S},
title = {Chemotropism Assays for Plant Symbiosis and Mycoparasitism Related Compound Screening in Trichoderma atroviride.},
journal = {Frontiers in microbiology},
volume = {11},
number = {},
pages = {601251},
pmid = {33329491},
issn = {1664-302X},
abstract = {Trichoderma atroviride is a mycoparasitic fungus used as biological control agent to protect plants against fungal pathogens. Successful biocontrol is based on the perception of signals derived from both the plant symbiont and the fungal prey. Here, we applied three different chemotropic assays to study the chemosensing capacity of T. atroviride toward compounds known or suspected to play a role in the mycoparasite/plant or host/prey fungal interactions and to cover the complete spectrum of T. atroviride developmental stages. Purified compounds, including nutrients, the fungal secondary metabolite 6-amyl-α-pyrone (6-pentyl-α-pyrone, 6-PP) and the plant oxylipin 13-(s)-HODE, as well as culture supernatants derived from fungal preys, including Rhizoctonia solani, Botrytis cinerea and Fusarium oxysporum, were used to evaluate chemotropic responses of conidial germlings, microcolonies and fully differentiated mycelia. Our results show that germlings respond preferentially to compounds secreted by plant roots and T. atroviride itself than to compounds secreted by prey fungi. With the progression of colony development, host plant cues and self-generated signaling compounds remained the strongest chemoattractants. Nevertheless, mature hyphae responded differentially to certain prey-derived signals. Depending on the fungal prey species, chemotropic responses resulted in either increased or decreased directional colony extension and hyphal density at the colony periphery closest to the test compound source. Together these findings suggest that chemotropic sensing during germling development is focused on plant association and colony network formation, while fungal prey recognition develops later in mature hyphae of fully differentiated mycelium. Furthermore, the morphological alterations of T. atroviride in response to plant host and fungal prey compounds suggest the presence of both positive and negative chemotropism. The presented assays will be useful for screening of candidate compounds, and for evaluating their impact on the developmental spectrum of T. atroviride and other related species alike. Conidial germlings proved particularly useful for simple and rapid compound screening, whereas more elaborate microscopic analysis of microcolonies and fully differentiated mycelia was essential to understand process-specific responses, such as plant symbiosis and biocontrol.},
}
@article {pmid33329456,
year = {2020},
author = {Walker, L and Lagunas, B and Gifford, ML},
title = {Determinants of Host Range Specificity in Legume-Rhizobia Symbiosis.},
journal = {Frontiers in microbiology},
volume = {11},
number = {},
pages = {585749},
pmid = {33329456},
issn = {1664-302X},
abstract = {Leguminous plants possess the almost unique ability to enter symbiosis with soil-resident, nitrogen fixing bacteria called rhizobia. During this symbiosis, the bacteria physically colonize specialized organs on the roots of the host plant called nodules, where they reduce atmospheric nitrogen into forms that can be assimilated by the host plant and receive photosynthates in return. In order for nodule development to occur, there is extensive chemical cross-talk between both parties during the formative stages of the symbiosis. The vast majority of the legume family are capable of forming root nodules and typically rhizobia are only able to fix nitrogen within the context of this symbiotic association. However, many legume species only enter productive symbiosis with a few, or even single rhizobial species or strains, and vice-versa. Permitting symbiosis with only rhizobial strains that will be able to fix nitrogen with high efficiency is a crucial strategy for the host plant to prevent cheating by rhizobia. This selectivity is enforced at all stages of the symbiosis, with partner choice beginning during the initial communication between the plant and rhizobia. However, it can also be influenced even once nitrogen-fixing nodules have developed on the root. This review sets out current knowledge about the molecular mechanisms employed by both parties to influence host range during legume-rhizobia symbiosis.},
}
@article {pmid33329441,
year = {2020},
author = {Li, R and Feng, Y and Chen, H and Zhang, C and Huang, Y and Chen, L and Hao, Q and Cao, D and Yuan, S and Zhou, X},
title = {Whole-Genome Sequencing of Bradyrhizobium diazoefficiens 113-2 and Comparative Genomic Analysis Provide Molecular Insights Into Species Specificity and Host Specificity.},
journal = {Frontiers in microbiology},
volume = {11},
number = {},
pages = {576800},
pmid = {33329441},
issn = {1664-302X},
abstract = {In the present study, we sequenced the complete genome of Bradyrhizobium diazoefficiens 113-2. The genomic characteristics of six selected rhizobial strains (two fast-growing rhizobia, two medium-slow-growing rhizobia and two slow-growing rhizobia) with four different legume hosts were analyzed by comparative genomic analysis. Genomes of B. diazoefficiens 113-2 and B. diazoefficiens USDA110 were found to share a large synteny blocks and a high ANI value, supporting 113-2 as a strain of B. diazoefficiens. 5,455 singletons and 11,656 clusters were identified among the six rhizobia genomes, and most of the pair-wise comparisons clusters were shared by the two genomes of strains in the same genus. Similar genus-specific gene numbers in the assigned COG functional terms were present in the two strains of the same genus, while the numbers were decreased with the increase of growth rate in most of the COG terms. KEGG pathway analysis of B. diazoefficiens 113-2 suggested that the rhizobial genes in ABC transporters and Two-Component system were mainly species-specific. Besides, the candidate genes related to secretion system and surface polysaccharides biosynthesis in the genomes of the six strains were explored and compared. 39 nodulation gene families, 12 nif gene families and 10 fix gene families in the genomes of these six strains were identified, and gene classes in most of gene families and the types and total gene numbers of gene families were substantially different among these six genomes. We also performed synteny analyses for above-mentioned nod, nif, and fix gene groupings, and selected NodW, NolK, NoeJ, NifB, FixK, and FixJ gene families to perform phylogeny analyses. Our results provided valuable molecular insights into species specificity and host specificity. The genetic information responsible for host specificity will play important roles in expanding the host range of rhizobia among legumes, which might provide new clues for the understanding of the genetic determinants of non-legume-rhizobium symbiosis.},
}
@article {pmid33329024,
year = {2020},
author = {Kirk, AL and Clowez, S and Lin, F and Grossman, AR and Xiang, T},
title = {Transcriptome Reprogramming of Symbiodiniaceae Breviolum minutum in Response to Casein Amino Acids Supplementation.},
journal = {Frontiers in physiology},
volume = {11},
number = {},
pages = {574654},
pmid = {33329024},
issn = {1664-042X},
abstract = {Dinoflagellates in the family Symbiodiniaceae can live freely in ocean waters or form a symbiosis with a variety of cnidarians including corals, sea anemones, and jellyfish. Trophic plasticity of Symbiodiniaceae is critical to its ecological success as it moves between environments. However, the molecular mechanisms underlying these trophic shifts in Symbiodiniaceae are still largely unknown. Using Breviolum minutum strain SSB01 (designated SSB01) as a model, we showed that Symbiodiniaceae go through a physiological and transcriptome reprogramming when the alga is grown with the organic nitrogen containing nutrients in hydrolyzed casein, but not with inorganic nutrients. SSB01 grows at a much faster rate and maintains stable photosynthetic efficiency when supplemented with casein amino acids compared to only inorganic nutrients or seawater. These physiological changes are driven by massive transcriptome changes in SSB01 supplemented with casein amino acids. The levels of transcripts encoding proteins involved in altering DNA conformation such as DNA topoisomerases, histones, and chromosome structural components were all significantly changed. Functional enrichment analysis also revealed processes involved in translation, ion transport, generation of second messengers, and phosphorylation. The physiological and molecular changes that underlie in vitro trophic transitions in Symbiodiniaceae can serve as an orthogonal platform to further understand the factors that impact the Symbiodiniaceae lifestyle.},
}
@article {pmid33328698,
year = {2020},
author = {Pröschold, T and Darienko, T},
title = {Choricystis and Lewiniosphaera gen. nov. (Trebouxiophyceae Chlorophyta), two different green algal endosymbionts in freshwater sponges.},
journal = {Symbiosis (Philadelphia, Pa.)},
volume = {82},
number = {3},
pages = {175-188},
pmid = {33328698},
issn = {0334-5114},
abstract = {Associations of freshwater sponges with coccoid green algae have been known for a long time. Two types of coccoid green algae, which are commonly assigned as zoochlorellae, are recognized by morphology: small coccoids (< 3 μm) without pyrenoids and larger Chlorella-like algae (4-6 μm) with pyrenoids. Despite their wide distribution in some freshwater sponges, these green algae were never studied using a combined analysis of morphology and molecular phylogeny. We investigated several endosymbiotic strains isolated from different Spongilla species, which were available in culture collections. Phylogenetic analyses of SSU and ITS rDNA sequences revealed that the strain SAG 211-40a is a member of the Chlorellaceae and represents a new species of the newly erected genus Lewiniosphaera, L symbiontica. The phylogenetic position was confirmed by morphology and ITS-2 barcode. The endosymbionts without pyrenoid were identified as Choricystis parasitica by morphology and phylogenetic analyses. The comparison with free-living strains revealed the recognition of two new Choricystis species, C. krienitzii and C. limnetica, which were confirmed by molecular signatures in V9 region of SSU rDNA and ITS-2 barcode.},
}
@article {pmid33327916,
year = {2020},
author = {Rajanala, K and Kumar, N and Chamallamudi, MR},
title = {Modulation of Gut-Brain Axis by probiotics: A promising anti-depressant approach.},
journal = {Current neuropharmacology},
volume = {},
number = {},
pages = {},
doi = {10.2174/1570159X19666201215142520},
pmid = {33327916},
issn = {1875-6190},
abstract = {The human digestive system is embedded with trillions of microbes of various species and genera. These organisms serve several purposes in human body and exist in symbiosis with the host. Their major role is involved in digestion and conversion of food materials into many useful substrates for human body. Apart from this, the gut microbiota also maintains healthy communication with other body parts including the brain. The connection between gut microbiota and brain is termed as Gut-Brain Axis (GBA) and these connections are established by neuronal, endocrine and immunological pathways. Thus, they are involved in neurophysiology and neuropathology of several diseases like Parkinson's Disease (PD), Alzheimer's Disease (AD), Depression and Autism. There are several food supplements such as prebiotics and probiotics the modulate the composition of gut microbiota. This article provides a review about the role of gut microbiota in depression and supplements such as probiotics that are useful in the treatment of depression.},
}
@article {pmid33326050,
year = {2021},
author = {Fiack, S and Koch-Gromus, U and Kuhn, J and Lübbing-Raukohl, C},
title = {[Medicine and media-symbiosis or conflict?].},
journal = {Bundesgesundheitsblatt, Gesundheitsforschung, Gesundheitsschutz},
volume = {64},
number = {1},
pages = {1-2},
doi = {10.1007/s00103-020-03262-0},
pmid = {33326050},
issn = {1437-1588},
}
@article {pmid33325846,
year = {2020},
author = {Li, Z and Kuan, YH and Mu, X and Miao, Z and Wu, C and Liao, WT},
title = {Ramsey interferometry through coherent A2Πu-X2Σg+-B2Σu+ coupling and population transfer in N2+ air laser.},
journal = {Optics letters},
volume = {45},
number = {24},
pages = {6587-6590},
doi = {10.1364/OL.401800},
pmid = {33325846},
issn = {1539-4794},
abstract = {Motivated by the hot debate on the mechanism of laser-like emission at 391 nm from N2 gas irradiated by a strong 800 nm pump laser and a weak 400 nm seed laser, we theoretically study the temporal profile, optical gain, and modulation of the 391 nm signal from N2+. Our calculation sheds light on the long standing controversy on whether population inversion is indispensable for optical gain and show the Ramsey fringes of the emission intensity at 391 nm formed by additionally injecting another 800 nm pump or 400 nm seed, which provides strong evidence for the coherence driven modulation of transition dipole moment and population transfer between the A2Πu(ν=2)-X2Σg+ states and the B2Σu+(ν=0)-X2Σg+ states. Our results show that the 391 nm optical gain is susceptible to the population inversion within N2+ states manipulated by the Ramsey technique and thus clearly reveal their symbiosis. This study reveals not only the physical picture of producing N2+ population inversion but also versatile control of the N2+ air laser.},
}
@article {pmid33324385,
year = {2020},
author = {Mironov, T and Sabaneyeva, E},
title = {A Robust Symbiotic Relationship Between the Ciliate Paramecium multimicronucleatum and the Bacterium Ca. Trichorickettsia Mobilis.},
journal = {Frontiers in microbiology},
volume = {11},
number = {},
pages = {603335},
pmid = {33324385},
issn = {1664-302X},
abstract = {Close reciprocal interactions in symbiotic systems have suggested the holobiont concept, in which the host and its microbiota are considered as a single entity. Ciliates are known for their ability to form symbiotic associations with prokaryotes. Relationships between the partners in such systems vary from mutualism to parasitism and differ significantly in their robustness. We assessed the viability of the ciliate Paramecium multimicronucleatum and its ability to maintain its intranuclear endosymbiont Ca. Trichorickettsia mobilis (Rickettsiaceae) after treatment with antibiotics characterized by different mode of action, such as ampicillin, streptomycin, chloramphenicol, tetracycline. The presence of endosymbionts in the host cell was determined by means of living cell observations made using differential interference contrast or fluorescence in situ hybridization with the species-specific oligonucleotide probe (FISH). Administration of antibiotics traditionally used in treatments of rickettsioses, tetracycline and chloramphenicol, depending on the concentration used and the ciliate strain treated, either caused death of both, infected and control cells, or did not affect the ability of the host to maintain the intranuclear endosymbiont. The surviving cells always manifested motile bacteria in the macronucleus. Streptomycin treatment never led to the loss of endosymbionts in any of the four infected strains, and nearly all ciliates remained viable. Ampicillin treatment never caused host cell death, but resulted in formation of filamentous and immobile oval bacterial forms. Under repeated ampicillin treatments, a part of endosymbionts was registered in the host cytoplasm, as evidenced both by FISH and transmission electron microscopy. Endosymbionts located in the host cytoplasm were enclosed in vacuoles, apparently, corresponding to autophagosomes. Nevertheless, the bacteria seemed to persist in this compartment and might cause relapse of the infection. Although the antibiotic sensitivity profile of Trichorickettsia seems to resemble that of other representatives of Rickettsiaceae, causative agents of severe diseases in humans, neither of the antibiotic treatments used in this study resulted in an aposymbiotic cell line, apparently, due to the protists' sensitivity to tetracyclines, the drugs of preference in rickettsiosis treatment. The observed robustness of this symbiotic system makes it a good model for further elaboration of the holobiont concept.},
}
@article {pmid33323417,
year = {2020},
author = {Zhou, J and Chai, X and Zhang, L and George, TS and Wang, F and Feng, G},
title = {Different Arbuscular Mycorrhizal Fungi Cocolonizing on a Single Plant Root System Recruit Distinct Microbiomes.},
journal = {mSystems},
volume = {5},
number = {6},
pages = {},
pmid = {33323417},
issn = {2379-5077},
abstract = {Plant roots are usually colonized by various arbuscular mycorrhizal (AM) fungal species, which vary in morphological, physiological, and genetic traits. This colonization constitutes the mycorrhizal nutrient uptake pathway (MP) and supplements the pathway through roots. Simultaneously, the extraradical hyphae of each AM fungus is associated with a community of bacteria. However, whether the community structure and function of the microbiome on the extraradical hyphae differ between AM fungal species remains unknown. In order to understand the community structure and the predicted functions of the microbiome associated with different AM fungal species, a split-root compartmented rhizobox cultivation system, which allowed us to inoculate two AM fungal species separately in two root compartments, was used. We inoculated two separate AM fungal species combinations, (i) Funneliformis mosseae and Gigaspora margarita and (ii) Rhizophagus intraradices and G. margarita, on a single root system of cotton. The hyphal exudate-fed, active microbiome was measured by combining 13C-DNA stable isotope probing with MiSeq sequencing. We found that different AM fungal species, which were simultaneously colonizing a single root system, hosted active microbiomes that were distinct from one another. Moreover, the predicted potential functions of the different microbiomes were distinct. We conclude that the arbuscular mycorrhizal fungal component of the system is responsible for the recruitment of distinct microbiomes in the hyphosphere. The potential significance of the predicted functions of the microbial ecosystem services is discussed.IMPORTANCE Arbuscular mycorrhizal (AM) fungi form tight symbiotic relationships with the majority of terrestrial plants and play critical roles in plant P acquisition, adding a further dimension of complexity. The plant-AM fungus-bacterium system is considered a continuum, with the bacteria colonizing not only the plant roots, but also the associated mycorrhizal hyphal network, known as the hyphosphere microbiome. Plant roots are usually colonized by different AM fungal species which form an independent phosphorus uptake pathway from the root pathway, i.e., the mycorrhizal pathway. The community structure and function of the hyphosphere microbiome of different AM species are completely unknown. In this novel study, we found that arbuscular mycorrhizal fungi cocolonizing on single plant roots recruit their own specific microbiomes, which should be considered in evaluating plant microbiome form and function. Our findings demonstrate the importance of understanding trophic interactions in order to gain insight into the plant-AM fungus-bacterium symbiosis.},
}
@article {pmid33323415,
year = {2020},
author = {Burgos, HL and Burgos, EF and Steinberger, AJ and Suen, G and Mandel, MJ},
title = {Multiplexed Competition in a Synthetic Squid Light Organ Microbiome Using Barcode-Tagged Gene Deletions.},
journal = {mSystems},
volume = {5},
number = {6},
pages = {},
pmid = {33323415},
issn = {2379-5077},
support = {R35 GM119627/GM/NIGMS NIH HHS/United States ; },
abstract = {Beneficial symbioses between microbes and their eukaryotic hosts are ubiquitous and have widespread impacts on host health and development. The binary symbiosis between the bioluminescent bacterium Vibrio fischeri and its squid host Euprymna scolopes serves as a model system to study molecular mechanisms at the microbe-animal interface. To identify colonization factors in this system, our lab previously conducted a global transposon insertion sequencing (INSeq) screen and identified over 300 putative novel squid colonization factors in V. fischeri To pursue mechanistic studies on these candidate genes, we present an approach to quickly generate barcode-tagged gene deletions and perform high-throughput squid competition experiments with detection of the proportion of each strain in the mixture by barcode sequencing (BarSeq). Our deletion approach improves on previous techniques based on splicing by overlap extension PCR (SOE-PCR) and tfoX-based natural transformation by incorporating a randomized barcode that results in unique DNA sequences within each deletion scar. Amplicon sequencing of the pool of barcoded strains before and after colonization faithfully reports on known colonization factors and provides increased sensitivity over colony counting methods. BarSeq enables rapid and sensitive characterization of the molecular factors involved in establishing the Vibrio-squid symbiosis and provides a valuable tool to interrogate the molecular dialogue at microbe-animal host interfaces.IMPORTANCE Beneficial microbes play essential roles in the health and development of their hosts. However, the complexity of animal microbiomes and general genetic intractability of their symbionts have made it difficult to study the coevolved mechanisms for establishing and maintaining specificity at the microbe-animal host interface. Model symbioses are therefore invaluable for studying the mechanisms of beneficial microbe-host interactions. Here, we present a combined barcode-tagged deletion and BarSeq approach to interrogate the molecular dialogue that ensures specific and reproducible colonization of the Hawaiian bobtail squid by Vibrio fischeri The ability to precisely manipulate the bacterial genome, combined with multiplex colonization assays, will accelerate the use of this valuable model system for mechanistic studies of how environmental microbes-both beneficial and pathogenic-colonize specific animal hosts.},
}
@article {pmid33323078,
year = {2020},
author = {Lyndby, NH and Rädecker, N and Bessette, S and Søgaard Jensen, LH and Escrig, S and Trampe, E and Kühl, M and Meibom, A},
title = {Amoebocytes facilitate efficient carbon and nitrogen assimilation in the Cassiopea-Symbiodiniaceae symbiosis.},
journal = {Proceedings. Biological sciences},
volume = {287},
number = {1941},
pages = {20202393},
doi = {10.1098/rspb.2020.2393},
pmid = {33323078},
issn = {1471-2954},
abstract = {The upside-down jellyfish Cassiopea engages in symbiosis with photosynthetic microalgae that facilitate uptake and recycling of inorganic nutrients. By contrast to most other symbiotic cnidarians, algal endosymbionts in Cassiopea are not restricted to the gastroderm but are found in amoebocyte cells within the mesoglea. While symbiont-bearing amoebocytes are highly abundant, their role in nutrient uptake and cycling in Cassiopea remains unknown. By combining isotopic labelling experiments with correlated scanning electron microscopy, and Nano-scale secondary ion mass spectrometry (NanoSIMS) imaging, we quantified the anabolic assimilation of inorganic carbon and nitrogen at the subcellular level in juvenile Cassiopea medusae bell tissue. Amoebocytes were clustered near the sub-umbrella epidermis and facilitated efficient assimilation of inorganic nutrients. Photosynthetically fixed carbon was efficiently translocated between endosymbionts, amoebocytes and host epidermis at rates similar to or exceeding those observed in corals. The Cassiopea holobionts efficiently assimilated ammonium, while no nitrate assimilation was detected, possibly reflecting adaptation to highly dynamic environmental conditions of their natural habitat. The motile amoebocytes allow Cassiopea medusae to distribute their endosymbiont population to optimize access to light and nutrients, and transport nutrition between tissue areas. Amoebocytes thus play a vital role for the assimilation and translocation of nutrients in Cassiopea, providing an interesting new model for studies of metabolic interactions in photosymbiotic marine organisms.},
}
@article {pmid33322342,
year = {2020},
author = {Flores-Félix, JD and Carro, L and Cerda-Castillo, E and Squartini, A and Rivas, R and Velázquez, E},
title = {Analysis of the Interaction between Pisum sativum L. and Rhizobium laguerreae Strains Nodulating This Legume in Northwest Spain.},
journal = {Plants (Basel, Switzerland)},
volume = {9},
number = {12},
pages = {},
pmid = {33322342},
issn = {2223-7747},
support = {AGL2013-48098-P//Ministerio de Ciencia e Innovación/ ; },
abstract = {Pisum sativum L. (pea) is one of the most cultivated grain legumes in European countries due to the high protein content of its seeds. Nevertheless, the rhizobial microsymbionts of this legume have been scarcely studied in these countries. In this work, we analyzed the rhizobial strains nodulating the pea in a region from Northwestern Spain, where this legume is widely cultivated. The isolated strains were genetically diverse, and the phylogenetic analysis of core and symbiotic genes showed that these strains belong to different clusters related to R. laguerreae sv. viciae. Representative strains of these clusters were able to produce cellulose and cellulases, which are two key molecules in the legume infection process. They formed biofilms and produced acyl-homoserine lactones (AHLs), which are involved in the quorum sensing regulation process. They also exhibited several plant growth promotion mechanisms, including phosphate solubilization, siderophore, and indole acetic acid production and symbiotic atmospheric nitrogen fixation. All strains showed high symbiotic efficiency on pea plants, indicating that strains of R. laguerreae sv. viciae are promising candidates for the biofertilization of this legume worldwide.},
}
@article {pmid33320798,
year = {2020},
author = {Medithi, S and Kasa, YD and Jee, B and Kodali, V and Jonnalagadda, PR},
title = {Organophosphate pesticide exposure among farm women and children: Status of micronutrients, acetylcholinesterase activity, and oxidative stress.},
journal = {Archives of environmental & occupational health},
volume = {},
number = {},
pages = {1-16},
doi = {10.1080/19338244.2020.1854646},
pmid = {33320798},
issn = {2154-4700},
abstract = {Nutritional status plays a major role in determining the possible adverse health outcomes due to pesticide toxicity. The objective of the present study was to assess the organophosphorus pesticide residue levels among farm women (FW) (24-45years) and farm children (FC) (9-12 and 13-15years) belonging to the Rangareddy district (Telangana, India) along with their micronutrient status, inhibition of acetylcholinesterase activity, and oxidative stress levels. Residues of Chlorpyrifos, Diazinon, Malathion, Monocrotophos and Phosalone were found in the serum samples of FW and FC along with significantly low levels of vitamins and minerals. Inhibition of AChE activity was observed in FW and FC and altered oxidative stress parameters among FW. Correlation studies have found significant associations between the pesticide residues, micronutrients and antioxidant enzymes. The study suggests an association between pesticide exposure coupled with micronutrient deficiency, induced AChE inhibition, and oxidative stress.},
}
@article {pmid33320473,
year = {2020},
author = {Zamłyńska, K},
title = {Structures of rhizobial lipopolysaccharides and their role in symbiosis process.},
journal = {Postepy biochemii},
volume = {66},
number = {1},
pages = {49-61},
doi = {10.18388/pb.2020_316},
pmid = {33320473},
issn = {0032-5422},
mesh = {Lipopolysaccharides/*chemistry/*metabolism ; Nitrogen Fixation ; Plants/*metabolism/*microbiology ; Rhizobium/*chemistry/*metabolism ; *Symbiosis ; },
}
@article {pmid33319429,
year = {2020},
author = {Neuenkamp, L and Zobel, M and Koorem, K and Jairus, T and Davison, J and Öpik, M and Vasar, M and Moora, M},
title = {Light availability and light demand of plants shape the arbuscular mycorrhizal fungal communities in their roots.},
journal = {Ecology letters},
volume = {},
number = {},
pages = {},
doi = {10.1111/ele.13656},
pmid = {33319429},
issn = {1461-0248},
support = {SLTOM20001T//Eesti Teadusagentuur/ ; PLTOM20903//University of Tartu/ ; SLTOM20001T//Estonian Research Council/ ; Centre of Excellence EcolChange//European Regional Development Fund/ ; },
abstract = {Plants involved in the arbuscular mycorrhizal (AM) symbiosis trade photosynthetically derived carbon for fungal-provided soil nutrients. However, little is known about how plant light demand and ambient light conditions influence root-associating AM fungal communities. We conducted a manipulative field experiment to test whether plants' shade-tolerance influences their root AM fungal communities in open and shaded grassland sites. We found similar light-dependent shifts in AM fungal community structure for experimental bait plant roots and the surrounding soil. Yet, deviation from the surrounding soil towards lower AM fungal beta-diversity in the roots of shade-intolerant plants in shade suggested preferential carbon allocation to specific AM fungi in conditions where plant-assimilated carbon available to fungi was limited. We conclude that favourable environmental conditions widen the plant biotic niche, as demonstrated here with optimal light availability reducing plants' selectivity for specific AM fungi, and promote compatibility with a larger number of AM fungal taxa.},
}
@article {pmid33317959,
year = {2020},
author = {Hedaoo, RP and Kabra, P and Gavaravarapu, SM},
title = {"Nutritainment" - A Nutrition Education Module for Indian Adolescents.},
journal = {Journal of nutrition education and behavior},
volume = {},
number = {},
pages = {},
doi = {10.1016/j.jneb.2020.11.002},
pmid = {33317959},
issn = {1878-2620},
}
@article {pmid33317774,
year = {2021},
author = {Ullah, J and Khanum, Z and Khan, IA and Khalid, AN and Musharraf, SG and Ali, A},
title = {Metaproteomics reveals the structural and functional diversity of Dermatocarpon miniatum (L.) W. Mann. Microbiota.},
journal = {Fungal biology},
volume = {125},
number = {1},
pages = {32-38},
doi = {10.1016/j.funbio.2020.10.001},
pmid = {33317774},
issn = {1878-6146},
abstract = {Metaproteomics is a strategy to understand the taxonomy, functionality and metabolic pathways of the microbial communities. The relationship among the symbiotic microbiota in the entire lichen thallus, Dermatocarpon miniatum, was evaluated using the metaproteomic approach. Proteomic profiling using one-dimensional SDS-PAGE followed by LC-MS/MS analysis resulted in a total of 138 identified proteins via Mascot search against UniRef100 and Swiss-Prot databases. In addition to the fungal and algal partners, D. miniatum proteome encompasses proteins from prokaryotes, which is a multifarious community mainly dominated by cyanobacteria and proteobacteria. While proteins assigned to fungus were the most abundant (55 %), followed by protists (16 %), bacterial (13 %), plant (11 %), and viral (1 %) origin, whereas 4 % remained undefined. Various proteins were assigned to the different lichen symbionts by using Gene Ontology (GO) terms, e.g. fungal proteins involved in the oxidation-reduction process, protein folding and glycolytic process, while protists and bacterial proteins were involved in photosynthetic electron transport in photosystem II (PS II), ATP synthesis coupled proton transport, and carbon fixation. The presence of bacterial communities extended the traditional concept of fungal-algal lichen symbiotic interaction.},
}
@article {pmid33317200,
year = {2020},
author = {Pujasatria, GC and Miura, C and Kaminaka, H},
title = {In Vitro Symbiotic Germination: A Revitalized Heuristic Approach for Orchid Species Conservation.},
journal = {Plants (Basel, Switzerland)},
volume = {9},
number = {12},
pages = {},
pmid = {33317200},
issn = {2223-7747},
abstract = {As one of the largest families of flowering plants, Orchidaceae is well-known for its high diversity and complex life cycles. Interestingly, such exquisite plants originate from minute seeds, going through challenges to germinate and establish in nature. Alternatively, orchid utilization as an economically important plant gradually decreases its natural population, therefore, driving the need for conservation. As with any conservation attempts, broad knowledge is required, including the species' interaction with other organisms. All orchids establish mycorrhizal symbiosis with certain lineages of fungi to germinate naturally. Since the whole in situ study is considerably complex, in vitro symbiotic germination study is a promising alternative. It serves as a tool for extensive studies at morphophysiological and molecular levels. In addition, it provides insights before reintroduction into its natural habitat. Here we reviewed how mycorrhiza contributes to orchid lifecycles, methods to conduct in vitro study, and how it can be utilized for conservation needs.},
}
@article {pmid33317178,
year = {2020},
author = {Tsyganov, VE and Tsyganova, AV},
title = {Symbiotic Regulatory Genes Controlling Nodule Development in Pisum sativum L.},
journal = {Plants (Basel, Switzerland)},
volume = {9},
number = {12},
pages = {},
pmid = {33317178},
issn = {2223-7747},
support = {17-76-30016//Russian Science Foundation/ ; },
abstract = {Analyses of natural variation and the use of mutagenesis and molecular-biological approaches have revealed 50 symbiotic regulatory genes in pea (Pisum sativum L.). Studies of genomic synteny using model legumes, such as Medicago truncatula Gaertn. and Lotus japonicus (Regel) K. Larsen, have identified the sequences of 15 symbiotic regulatory genes in pea. These genes encode receptor kinases, an ion channel, a calcium/calmodulin-dependent protein kinase, transcription factors, a metal transporter, and an enzyme. This review summarizes and describes mutant alleles, their phenotypic manifestations, and the functions of all identified symbiotic regulatory genes in pea. Some examples of gene interactions are also given. In the review, all mutant alleles in genes with identified sequences are designated and still-unidentified symbiotic regulatory genes of great interest are considered. The identification of these genes will help elucidate additional components involved in infection thread growth, nodule primordium development, bacteroid differentiation and maintenance, and the autoregulation of nodulation. The significance of symbiotic mutants of pea as extremely fruitful genetic models for studying nodule development and for comparative cell biology studies of legume nodules is clearly demonstrated. Finally, it is noted that many more sequences of symbiotic regulatory genes remain to be identified. Transcriptomics approaches and genome-wide sequencing could help address this challenge.},
}
@article {pmid33316994,
year = {2020},
author = {Baranova, AA and Chistov, AA and Tyurin, AP and Prokhorenko, IA and Korshun, VA and Biryukov, MV and Alferova, VA and Zakalyukina, YV},
title = {Chemical Ecology of Streptomycesalbidoflavus Strain A10 Associated with Carpenter Ant Camponotus vagus.},
journal = {Microorganisms},
volume = {8},
number = {12},
pages = {},
pmid = {33316994},
issn = {2076-2607},
support = {20-33-70215//Russian Foundation for Basic Research/ ; },
abstract = {Antibiotics produced by symbiotic microorganisms were previously shown to be of crucial importance for ecological communities, including ants. Previous works on ant-actinobacteria symbiosis are mainly focused on farming ants, which use antifungal microbial secondary metabolites to control pathogens in their fungal gardens. In this work, we studied microorganisms associated with carpenter ant Camponotus vagus. Pronounced antifungal activity of isolated actinobacteria strain A10 was found to be facilitated by biosynthesis of the antimycin A complex, consisting of small hydrophobic depsipeptides with high antimicrobial and cytotoxic activity. The actinomycete strain A10 was identified as Streptomyces albidoflavus. We studied the antagonistic activity of strain A10 against several entomopathogenic microorganisms. The antifungal activity of this strain potentially indicates a defensive symbiosis with the host ant, producing antimycins to protect carpenter ants against infections. The nature of this ant-microbe association however remains to be established.},
}
@article {pmid33315317,
year = {2020},
author = {Jarzyniak, K},
title = {The role of cytokinins in Legume-Rhizobium symbiosis.},
journal = {Postepy biochemii},
volume = {66},
number = {3},
pages = {229-238},
doi = {10.18388/pb.2020_343},
pmid = {33315317},
issn = {0032-5422},
mesh = {Cytokinins/*metabolism ; Fabaceae/*metabolism/*microbiology ; Plant Growth Regulators/metabolism ; Plant Roots/metabolism/microbiology ; Rhizobium/*metabolism ; Signal Transduction ; *Symbiosis ; },
abstract = {Legume plants have a unique ability to form associations with nitrogen-fixing rhizobial species. An exchange of specific signaling molecules between host and microsymbiont constitutes the first step required both for bacterial infection and the formation of new, root-derived organs, called nodules. Since these two events occur in different root tissues, namely in the rhizodermis and in the underlying cortical cells, their strict regulation and coordination have to exist. An essential role of plant hormones, especially cytokinins, in the modulation of nitrogen-fixing symbiosis has been widely postulated. Activation of the cytokinin signaling pathway in the root cortex, by an unknown signal, is thought to be a key event of the infection process. As a consequence bioactive cytokinins are biosynthesized in the root susceptible zone, and they are a part of a positive feedback loop to trigger cortical cell division and sustain nodule organogenesis. Understanding the genetic mechanisms underlying events that occur in the inner layers of the root is one of the key challenges emerging in the study of symbiotic processes.},
}
@article {pmid33315312,
year = {2020},
author = {Jarzyniak, K},
title = {Role of ABCG transporters in modulation of symbiotic interactions.},
journal = {Postepy biochemii},
volume = {66},
number = {3},
pages = {239-244},
doi = {10.18388/pb.2020_349},
pmid = {33315312},
issn = {0032-5422},
mesh = {ATP Binding Cassette Transporter, Subfamily G/*metabolism ; Animals ; Evolution, Molecular ; Humans ; Phylogeny ; Plants/metabolism ; *Symbiosis ; },
abstract = {ABC proteins, which include ABCG transporters, form one of the largest and most evolutionarily conserved protein families found in all systematic groups. Their function is associated with the active transport of several structurally and functionally unrelated compounds across cell membranes. All members of this protein family have a characteristic domain organization, which quantity and orientation determine their division and classification into subfamilies. ABCGs are recognized as being crucial for plant development as well as interactions with the environment. However, researchers have only just begun to discover the role of ABCG transporters as important modulators of symbioses.},
}
@article {pmid33314850,
year = {2020},
author = {Sun, SM and Chang, W and Song, FQ},
title = {[Mechanism of arbuscular mycorrhizal fungi improve the oxidative stress to the host plants under salt stress: A review].},
journal = {Ying yong sheng tai xue bao = The journal of applied ecology},
volume = {31},
number = {10},
pages = {3589-3596},
doi = {10.13287/j.1001-9332.202010.040},
pmid = {33314850},
issn = {1001-9332},
mesh = {Ecosystem ; *Mycorrhizae ; Oxidative Stress ; Plant Roots ; Plants ; Salt Stress ; Symbiosis ; },
abstract = {Soil salinization induced by the dual effects of natural environment and human activities is a serious ecological problem globally. Salinization caused osmotic imbalance, ion stress, oxidative damage, and other hazards to plants, leading to retard, reduce biomass and even total crop failure. Arbuscular mycorrhizal fungi (AMF) is a group of beneficial microorganism with wide distribution. AMF can form symbiotic relationship with most plant roots, with ecological significance in various stressed ecosystems. Because of the highly effective antioxidative system in symbionts, AMF could improve plant anti-oxidative response under salt stress and enhance their tolerance to salt stress. Here, we reviewed the research progress of arbuscular mycorrhizal symbiosis in improing plant antioxidative mechanism, including oxidative damage, osmotic regulation, antio-xidant mechanism and bioactive molecules. Finally, research prospects were proposed to provide theoritical support for improving plant salt tolerance by mycorrhizal biotechnology.},
}
@article {pmid33314845,
year = {2020},
author = {Xu, X and Liu, T and Kong, XQ and Chen, JQ and Chen, LD and Huang, S and Sun, SJ},
title = {[Effects of sawdust dosage on the diversity and community structure of bacteria associated with the hyphae of Pleurotus eryngii].},
journal = {Ying yong sheng tai xue bao = The journal of applied ecology},
volume = {31},
number = {10},
pages = {3547-3553},
doi = {10.13287/j.1001-9332.202010.036},
pmid = {33314845},
issn = {1001-9332},
mesh = {*Bacteria ; Humans ; *Hyphae ; Pleurotus ; RNA, Ribosomal, 16S ; Wood ; },
abstract = {Some fungi engage symbiosis with bacteria, which can effectively promote the metabolism and growth of fungi. The diversity and community structure of bacteria can reflect the growth and substrate utilization of fungi. In this study, we analyzed the effects of different sawdust dosages on the community structure and diversity of bacteria associated with the hyphae of Pleurotus eryngii using high-throughput sequencing technology (HST) based on PCR-amplified 16S rRNA V3-V4 fragments. The results showed that the high-quality sequences from five groups of mycelia samples were clustered into 25 phyla, 52 classes, 114 orders, 199 families, and 406 genera. Proteobacteria (35.0%-85.9%) and Firmicutes (6.5%-38.4%) were the most abundant bacterial phyla, while Acinetobacter (14.8%-71.6%) and Pseudomonas (1.7%-22.3%) were the dominant symbiotic genera. Compared with the mycelia grown on the complete culture medium, sawdust addition could increase the diversity of bacteria coexisting with P. eryngii mycelia, and change the community structure of 10 dominant phyla and 9 dominant genera. P. eryngii cultivated in substrate containing 5 g sawdust had the fastest mycelium growth rate, thick mycelia, and neatly edges. Furthermore, judging from the abundance and diversity, Pseudomonas and Lactobacillus became the dominant genera, which were positively correlated with the mycelia growth vigour. Sawdust, as an important carbon source, could affect the growth and development of P. eryngii and the community structure and diversity of bacteria coexisting with mycelia. This study would lay a theoretical foundation for exploring the molecular mechanism of sawdust and mycelium symbiosis affecting the growth and development of P. eryngii.},
}
@article {pmid33314556,
year = {2020},
author = {Kumar, N and Galli, M and Dempsey, D and Imani, J and Moebus, A and Kogel, KH},
title = {NPR1 is required for root colonization and the establishment of a mutualistic symbiosis between the beneficial bacterium Rhizobium radiobacter and barley.},
journal = {Environmental microbiology},
volume = {},
number = {},
pages = {},
doi = {10.1111/1462-2920.15356},
pmid = {33314556},
issn = {1462-2920},
support = {//DAAD/ ; //PrimedPlant consortium/ ; },
abstract = {Non-expressor of pathogenesis-related genes 1 (NPR1) is a key regulator of plant innate immunity and systemic disease resistance. The model for NPR1 function is based on experimental evidence obtained largely from dicots; however, this model does not fit all aspects of Poaceae family, which includes major crops such as wheat, rice and barley. In addition, there is little scientific data on NPR1's role in mutualistic symbioses. We assessed barley (Hordeum vulgare) HvNPR1 requirement during the establishment of mutualistic symbiosis between barley and beneficial Alphaproteobacterium Rhizobium radiobacter F4 (RrF4). Upon RrF4 root-inoculation, barley NPR1-knockdown (KD-hvnpr1) plants lost the typical spatiotemporal colonization pattern and supported less bacterial multiplication. Following RrF4 colonization, expression of salicylic acid marker genes were strongly enhanced in wild-type roots; whereas in comparison, KD-hvnpr1 roots exhibited little to no induction. Both basal and RrF4-induced root-initiated systemic resistance against virulent Blumeria graminis were impaired in leaves of KD-hvnpr1. Besides these immune-related differences, KD-hvnpr1 plants displayed higher root and shoot biomass than WT. However, RrF4-mediated growth promotion was largely compromised in KD-hvnpr1. Our results demonstrate a critical role for HvNPR1 in establishing a mutualistic symbiosis between a beneficial bacterium and a cereal crop.},
}
@article {pmid33314486,
year = {2020},
author = {Bapat, S and Jaspal, D and Malviya, A},
title = {Integrated textile effluent treatment method.},
journal = {Water environment research : a research publication of the Water Environment Federation},
volume = {},
number = {},
pages = {},
doi = {10.1002/wer.1494},
pmid = {33314486},
issn = {1554-7531},
abstract = {Textile wastewater purification is a challenging process. Conventional wastewater treatment methods either lack in efficiency, cost-effectiveness or leads to the generation of secondary pollutants. Additionally, some treatment methods are time-consuming. The research presented in the manuscript is a blend of filtration, biosorption, aeration, solar energy-assisted electrolytic precipitation, pH balance, and germicidal treatments with an aim of reducing the suspended solids, intense color, odor, pH, chemical oxygen demand (COD), total dissolved solids (TDS), electrical conductivity (EC), and heavy metal content of textile effluent. Use of environmentally sustainable surface activated biosorbents derived from waste weeds Water Hyacinth (WH) and Parthenium Hysterophorus (PH) as an alternative to commercial grade Activated Charcoal (AC), comparison of adsorption capacities of proposed adsorbents against AC for effluent decolorization, the application of solar energy to run an electrolytic precipitator, and the unique sequential design of various unit processes like coarse and fine filtration, biosorption, aeration, electrolytic precipitation, pH treatment and germicidal UV-C treatment to treat the effluent are some of the novel methodologies explored in the present study. The invented process provides almost completely decolorized (about 90%-94%), particle-free and odorless treated water, with the acceptable levels of heavy metals (Lead-not detected, Arsenic-not detected, Zinc-0.5-0.8 mg/L), TDS (1,500-1,850 mg/L), COD (149-169 mg/L) pH (7.1-7.15), and EC (2.5-2.8 mMhos/cm) as some of the important parameters, fitting well within the standard pollution limits. Performance efficiency estimation and statistical modeling were done for the data using the t test and f test. The values obtained were (t = 2.78 and f = 4.99 for treated WH against AC) and (t = 3.00 and f = 5.38 for treated PH against AC at 0.05 level of significance) as an essential part of the manuscript, proving the supremacy of the proposed process to achieve the standard pollution norms. Cost-effectiveness was an integral factor addressed in the proposed design, recorded a 1.7 USD per 1,000 L of input effluent, which was well below than most of the reported studies. The invented method in the present investigation thus provides an integrated, efficient, eco-friendly, and cost-effective solution to wastewater treatment. PRACTITIONER POINTS: Effluent decolorization is about 68% in comparison with conventional activated carbon. The adsorbent was found to be three times more active than activated carbon. COD value decreased from 2,352 mg/L to about 150 mg/L on treatment with the novel adsorbent.},
}
@article {pmid33310352,
year = {2020},
author = {Hei, Y and Zhang, H and Tan, N and Zhou, Y and Wei, X and Hu, C and Liu, Y and Wang, L and Qi, J and Gao, JM},
title = {Antimicrobial activity and biosynthetic potential of cultivable actinomycetes associated with Lichen symbiosis from Qinghai-Tibet Plateau.},
journal = {Microbiological research},
volume = {244},
number = {},
pages = {126652},
doi = {10.1016/j.micres.2020.126652},
pmid = {33310352},
issn = {1618-0623},
abstract = {Actinobacteria that inhabit lichen symbionts are considered a promising yet previously underexplored source of novel compounds. Here, for the first time, we conducted a comprehensive investigation with regard to strain isolation and identification of lichen-associated actinobacteria from Tibet Plateau, antimicrobial activity screening, biosynthetic genes detection, bioactive metabolites identification and activity prediction. A large number of culturable actinomycetes were isolated from lichens around Qinghai Lake, in Qinghai-Tibet Plateau. Twenty-seven strains with distinct morphological characteristics were preliminarily studied. 16S rRNA gene identification showed that 13 strains were new species. The PCR-screening of specific biosynthetic genes indicated that these 27 isolates had abundant intrinsic biosynthetic potential. The antimicrobial activity experiment screened out some potential biological control antagonistic bacteria. The metabolites of 13 strains of Streptomyces with antibacterial activity were analyzed by LC-HRMS, and further 18 compounds were identified by NMR and / or LC-HRMS. The identified compounds were mainly pyrrolidine and indole derivatives, as well as anthracyclines. Seven compounds were identified with less biological activity, then predicted and evaluated their biological activity. The predicted results showed that compound 2 had excellent inhibitory activity on HIV-1 reverse transcriptase. Overall, the results indicate actinobacteria isolated from unexploited plateau lichen are promising sources of biological active metabolite, which could provide important bioactive compounds as potential antibiotic drugs.},
}
@article {pmid33309968,
year = {2020},
author = {Grabovich, MY and Gureeva, MV and Dubinina, GA},
title = {The role of the "Thiodendron" consortium in postulating the karyomastigont chimaera of the endosymbiosis theory by Lynn Margulis.},
journal = {Bio Systems},
volume = {200},
number = {},
pages = {104322},
doi = {10.1016/j.biosystems.2020.104322},
pmid = {33309968},
issn = {1872-8324},
abstract = {The endosymbiosis theory of the origin of eukaryotic cell was first proposed more than a hundred years ago. In the second half of the 20th century, Lynn Margulis suggested a new interpretation of the origin of the nucleus in modern eukaryotes. The background was the study of the consortium "Thiodendron", a symbiotic bacterial community, which includes anaerobic aerotolerant motile spirochaetes and sulfidogenic bacteria (sulfidogens) of vibrioid form with a fermentation type of metabolism. Spirochaetes supply sulfidogens with metabolites (pyruvate and, probably, organic nitrogenous products of cell lysis) and get hydrogen sulfide from sulfidogens that helps to maintain a low redox potential. At low oxygen concentrations, spirochaetes are able to assimilate glucose more efficiently. Margulis hypothesized about the symbiotic origin of the nucleus by adding the bacterium Spirochaeta to the Thermoplasma-like archaea. She considered the "Thiodendron"-like consortium to be an intermediate stage in evolution. According to Margulis, the conversion of carbohydrates and the oxidation of Н2S to S0 by the bacterium provided the archaea with electron acceptors for anaerobic respiration, as shown for modern thermoplasmas and products saturated with carbon. The use of carbon sources increased by attaching the floating bacterium to the archaea. More efficient microaerobic oxidation of glucose pre-adapted the spirochaetes for association with Thermoplasma. However, modern "Thiodendron"-like consortia are not in stable symbiosis and a sulfidogenic component of the consortium is capable for fermentation, rather than anaerobic respiration, which makes the theory by Margulis disputable.},
}
@article {pmid33309942,
year = {2020},
author = {Wang, X and Feng, H and Wang, Y and Wang, M and Xie, X and Chang, H and Wang, L and Qu, J and Sun, K and He, W and Wang, C and Dai, C and Chu, Z and Tian, C and Yu, N and Zhang, X and Liu, H and Wang, E},
title = {Mycorrhizal Symbiosis Modulates the Rhizosphere Microbiota to Promote Rhizobia-Legume Symbiosis.},
journal = {Molecular plant},
volume = {},
number = {},
pages = {},
doi = {10.1016/j.molp.2020.12.002},
pmid = {33309942},
issn = {1752-9867},
abstract = {Plants establish symbioses with mutualistic fungi, such as arbuscular mycorrhizal (AM) fungi, and bacteria, such as rhizobia, to exchange key nutrients and thrive. The plants and symbionts have coevolved and represent vital components of terrestrial ecosystems. Plants employ an ancestral AM signaling pathway to establish intracellular symbioses, including the legume-rhizobia symbiosis, in their roots. Nevertheless, the relationship between the AM and rhizobial symbioses in native soil is poorly understood. Here, we examined how these distinct symbioses affect root-associated bacterial communities in Medicago truncatula, by quantitative microbiota profiling (QMP) of 16S rRNA genes. We found that M. truncatula mutants that cannot establish AM or rhizobia symbiosis have an altered microbial load (quantitative abundance) in rhizosphere and roots, and in particular that AM symbiosis is required to assemble a normal quantitative root-associated microbiota in native soil. Moreover, quantitative microbial co-abundance network analyses revealed that the AM symbiosis impacts Rhizobiales-hubs among the plant microbiota and benefit the plant holobiont. Through QMP of rhizobial rpoB and AM fungal SSU rRNA genes, we revealed a new layer of interaction, whereby AM symbiosis promotes rhizobia accumulation in the rhizosphere of M. truncatula. We further showed that AM symbiosis-conditioned microbial communities within the M. truncatula rhizosphere could promote nodulation in different legume plants in native soil. Given that the AM and rhizobial symbioses are critical for crop growth, our findings might inform strategies to improve agricultural management. Moreover, our work sheds light on the co-evolution of these intracellular symbioses during plant adaptation to native soil conditions.},
}
@article {pmid33308015,
year = {2020},
author = {Schertzer, JD and Lam, TKT},
title = {Peripheral and central regulation of insulin by the intestine and microbiome.},
journal = {American journal of physiology. Endocrinology and metabolism},
volume = {},
number = {},
pages = {},
doi = {10.1152/ajpendo.00547.2020},
pmid = {33308015},
issn = {1522-1555},
support = {FDN-154295//Gouvernement du Canada | Canadian Institutes of Health Research (Instituts de recherche en santé du Canada)/ ; FDN-143204//Gouvernement du Canada | Canadian Institutes of Health Research (Instituts de recherche en santé du Canada)/ ; MRT-168045//Gouvernement du Canada | Canadian Institutes of Health Research (Instituts de recherche en santé du Canada)/ ; MRT-168045//Gouvernement du Canada | Canadian Institutes of Health Research (Instituts de recherche en santé du Canada)/ ; },
abstract = {Blood glucose and insulin homeostasis is disrupted during the progression of type 2 Diabetes. Insulin levels and action are regulated by both peripheral and central responses that involve the intestine and microbiome. The intestine and its microbiota process nutrients and generate molecules that influence blood glucose and insulin. Peripheral insulin regulation is regulated by gut-segment dependent nutrient sensing and microbial factors such as short chain fatty acids and bile acids that engage G-protein coupled receptors. Innate immune sensing of gut-derived bacterial cell wall components and lipopolysaccharides also alter insulin homeostasis. These bacterial metabolites and postbiotics influence insulin secretion and insulin clearance in part by altering endocrine responses such as glucagon-like peptide-1. Gut-derived bacterial factors can promote inflammation and insulin resistance, but other postbiotics can be insulin sensitizers. In parallel, activation of small intestinal sirtuin 1 increases insulin sensitivity by reversing high-fat induced hypothalamic insulin resistance through a gut-brain neuronal axis, while high-fat feeding alters small intestinal microbiome and increases taurochenodeoxycholic acid in the plasma and the dorsal vagal complex to induce insulin resistance. In summary, emerging evidence indicates that intestinal molecular signaling involving nutrient sensing and the host-microbe symbiosis alter insulin homeostasis and action. Gut-derived host endocrine and paracrine factors as well as microbial metabolites act on the liver, pancreas, the brain and in parallel on the gut-brain neuronal axis. Understanding common nodes of peripheral and central insulin homeostasis and action may reveal new ways to target the intestinal host-microbe relationship in obesity, metabolic disease and type 2 diabetes.},
}
@article {pmid33306279,
year = {2020},
author = {Jiménez-Guerrero, I and Moreno-De Castro, N and Pérez-Montaño, F},
title = {One door closes, another opens: when nodulation impairment with natural hosts extends rhizobial host-range.},
journal = {Environmental microbiology},
volume = {},
number = {},
pages = {},
doi = {10.1111/1462-2920.15353},
pmid = {33306279},
issn = {1462-2920},
support = {US-1250546//Consejería de Economía, Innovación, Ciencia y Empleo, Junta de Andalucía/ ; US-1259948//Consejería de Economía, Innovación, Ciencia y Empleo, Junta de Andalucía/ ; PID2019-107634RB-I00//Ministerio de Ciencia e Innovación/ ; },
abstract = {The rhizobium-legume symbiosis is the best-understood plant-microbe association. The high degree of specificity observed in this relationship is supported by a complex exchange of signals between the two components of the symbiosis. Findings reported in last years indicate that multiple molecular mechanisms, such as the production of a particular set of nodulation factors at a very specific concentration or a suitable arsenal of effectors secreted through the type III secretion system, have been adjusted during evolution to ensure and optimize the recognition of specific rhizobial strains by its legume host. Qualitative or quantitative changes in the production of these symbiotic molecular determinants are detrimental for nodulation with its natural host but, in some cases, can also result beneficial for the rhizobium since it extends the nodulation host-range to other legumes. Potential repercussion of the extension in the nodulation host-range of rhizobia is discussed.},
}
@article {pmid33306193,
year = {2020},
author = {Rammitsu, K and Yukawa, T and Yamashita, Y and Isshiki, S and Ogura-Tsujita, Y},
title = {The mycorrhizal community of the epiphytic orchid Thrixspermum japonicum is strongly biased toward a single Ceratobasidiaceae fungus, despite a wide range of fungal partners.},
journal = {American journal of botany},
volume = {107},
number = {12},
pages = {1654-1662},
doi = {10.1002/ajb2.1575},
pmid = {33306193},
issn = {1537-2197},
support = {17K07536//JSPS/ ; 18H02500//JSPS/ ; //Yakushima Environmental and Cultural Foundation/ ; },
abstract = {PREMISE: Orchids depend primarily on mycorrhizal fungi to obtain nutrients throughout their life cycle. Epiphytic orchids account for 69% of orchid diversity. The unstable availability of water and nutrients in their arboreal habitats often results in severe water and nutrient stresses. Consequently, mycorrhizal associations may be important for the survival of epiphytic orchids, but our understanding thereof remains limited. Here, we investigated the mycorrhizal community in a single epiphytic orchid species, using more samples than in any previous study.
METHODS: We assessed the mycorrhizal communities of Thrixspermum japonicum, one of the most common epiphytic orchids in the temperate region of Japan. In total, 144 individuals were collected from 28 host tree species at 20 sites across 1300 km. The mycorrhizal fungi were identified based on nuclear ribosomal DNA internal transcribed spacer sequences and assigned operational taxonomic units (OTUs) based on 97% sequence similarity.
RESULTS: We obtained 24 OTUs; 9 belonged to the Ceratobasidiaceae and 15 to the Tulasnellaceae. These OTUs are widely distributed throughout the phylogenetic trees of the two fungal families. However, a single Ceratobasidiaceae OTU accounted for 49.7% of all fungal sequences and was predominant in samples from 15 host tree species and 12 sites.
CONCLUSIONS: Our results imply that despite having a broad range of mycorrhizal partners, T. japonicum was predominantly associated with a single fungal taxon at most of the sites among the host-tree species investigated. These findings contribute to elucidating mycorrhizal symbiosis in epiphytic habitats.},
}
@article {pmid33305497,
year = {2020},
author = {Mu, R and Jia, Y and Ma, G and Liu, L and Hao, K and Qi, F and Shao, Y},
title = {Advances in the Use of Microalgal-Bacterial Consortia for Wastewater Treatment: Community Structures, Interactions, Economic Resource Reclamation and Study Techniques.},
journal = {Water environment research : a research publication of the Water Environment Federation},
volume = {},
number = {},
pages = {},
doi = {10.1002/wer.1496},
pmid = {33305497},
issn = {1554-7531},
abstract = {The rise in living standards has generated a demand for higher aquatic environmental quality. The microalgal community and the surrounding organic molecules, environmental factors and microorganisms, such as bacteria, are together defined as the phycosphere. The bacteria in the phycosphere can form consortia with microalgae through various forms of interaction. The study of the species in these consortia and their relative proportions is of great significance in determining the species and strains of stable algae that can be used in sewage treatment. This article summarizes the following topics: the interactions between microalgae and bacteria that are required to establish consortia; how symbiosis between algae and bacteria is established; microalgal competition with bacteria through inhibition and anti-inhibition strategies; the influence of environmental factors on microalgal-bacterial aggregates, such as illumination conditions, pH, dissolved oxygen, temperature and nutrient levels; the application of algal-bacterial aggregates to enhance biomass production and nutrient reuse; and techniques for studying the community structure and interactions of algal-bacterial consortia, such as microscopy, flow cytometry, and omics.},
}
@article {pmid33304528,
year = {2020},
author = {Shu, L and Qian, X and Brock, DA and Geist, KS and Queller, DC and Strassmann, JE},
title = {Loss and resiliency of social amoeba symbiosis under simulated warming.},
journal = {Ecology and evolution},
volume = {10},
number = {23},
pages = {13182-13189},
pmid = {33304528},
issn = {2045-7758},
abstract = {Anthropogenic global change is increasingly raising concerns about collapses of symbiotic interactions worldwide. Therefore, understanding how climate change affects symbioses remains a challenge and demands more study. Here, we look at how simulated warming affects the social ameba Dictyostelium discoideum and its relationship with its facultative bacterial symbionts, Paraburkholderia hayleyella and Paraburkholderia agricolaris. We cured and cross-infected ameba hosts with different symbionts. We found that warming significantly decreased D. discoideum's fitness, and we found no sign of local adaptation in two wild populations. Experimental warming had complex effects on these symbioses with responses determined by both symbiont and host. Neither of these facultative symbionts increases its hosts' thermal tolerance. The nearly obligate symbiont with a reduced genome, P. hayleyella, actually decreases D. discoideum's thermal tolerance and even causes symbiosis breakdown. Our study shows how facultative symbioses may have complex responses to global change.},
}
@article {pmid33304460,
year = {2020},
author = {Jiao, J and Tian, CF},
title = {Ancestral zinc-finger bearing protein MucR in alpha-proteobacteria: A novel xenogeneic silencer?.},
journal = {Computational and structural biotechnology journal},
volume = {18},
number = {},
pages = {3623-3631},
pmid = {33304460},
issn = {2001-0370},
abstract = {The MucR/Ros family protein is conserved in alpha-proteobacteria and characterized by its zinc-finger motif that has been proposed as the ancestral domain from which the eukaryotic C2H2 zinc-finger structure evolved. In the past decades, accumulated evidences have revealed MucR as a pleiotropic transcriptional regulator that integrating multiple functions such as virulence, symbiosis, cell cycle and various physiological processes. Scattered reports indicate that MucR mainly acts as a repressor, through oligomerization and binding to multiple sites of AT-rich target promoters. The N-terminal region and zinc-finger bearing C-terminal region of MucR mediate oligomerization and DNA-binding, respectively. These features are convergent to those of xenogeneic silencers such as H-NS, MvaT, Lsr2 and Rok, which are mainly found in other lineages. Phylogenetic analysis of MucR homologs suggests an ancestral origin of MucR in alpha- and delta-proteobacteria. Multiple independent duplication and lateral gene transfer events contribute to the diversity and phyletic distribution of MucR. Finally, we posed questions which remain unexplored regarding the putative roles of MucR as a xenogeneic silencer and a general manager in balancing adaptation and regulatory integration in the pangenome context.},
}
@article {pmid33303659,
year = {2020},
author = {Mead, OL and Gueidan, C},
title = {Complete Genome Sequence of an Australian Strain of the Lichen-Forming Fungus Endocarpon pusillum (Hedwig).},
journal = {Microbiology resource announcements},
volume = {9},
number = {50},
pages = {},
pmid = {33303659},
issn = {2576-098X},
abstract = {The cosmopolitan lichen-forming fungus Endocarpon pusillum (Hedwig) has previously been used as a model for the study of symbiosis and drought resistance. Here, we present the annotated genome of the Australian strain Endocarpon pusillum EPUS1.4. This genome sequence provides additional information on the ability of this species to produce secondary metabolites.},
}
@article {pmid33301842,
year = {2020},
author = {Ferrer, B and Prince, LM and Tinkov, AA and Santamaria, A and Bowman, AB and Aschner, M},
title = {Chronic exposure to methylmercury disrupts ghrelin actions in C57BL/6J mice.},
journal = {Food and chemical toxicology : an international journal published for the British Industrial Biological Research Association},
volume = {147},
number = {},
pages = {111918},
doi = {10.1016/j.fct.2020.111918},
pmid = {33301842},
issn = {1873-6351},
abstract = {Methylmercury (MeHg) is a neurotoxic pollutant widely present in the environment. Initial symptoms of MeHg may include loss of body weight. However, the mechanisms by which MeHg induces body weight changes have yet to be fully elucidated. Body weight is regulated by multiple mechanisms. Whereas multiple peripheral peptides lead to food intake cessation, ghrelin is the only recognized peripheral hormone that stimulates food intake. It exerts its action on Neuropeptide Y/Agouti-related peptide neurons in the hypothalamus. To test if MeHg affects ghrelin signaling C57BL/6J mice (males and females) were exposed to 5 ppm MeHg via drinking water during a month. On days 15 and 30 of MeHg exposure ghrelin was administered intraperitoneally and changes in body weight and food intake were recorded. In addition, changes in ghrelin-induced signaling pathways in hypothalamus were also analyzed. Here, we show that in males, MeHg enhanced ghrelin-induced body weight gain by activating the AMP-activated Kinase (AMPK)/Uncoupled protein 2 (UCP2) signaling pathway. In contrast, in females, MeHg inhibited ghrelin-induced mTOR signaling activation and decreased Npy mRNA expression, thus mitigating the ghrelin-induced weight gain. Combined, our novel results demonstrate, for the first time, that MeHg disrupts the physiological functions of ghrelin differently in males and females.},
}
@article {pmid33300250,
year = {2020},
author = {Chen, WF and Wang, ET and Ji, ZJ and Zhang, JJ},
title = {Recent development and new insight of diversification and symbiosis specificity of legume rhizobia: mechanism and application.},
journal = {Journal of applied microbiology},
volume = {},
number = {},
pages = {},
doi = {10.1111/jam.14960},
pmid = {33300250},
issn = {1365-2672},
abstract = {Currently, symbiotic rhizobia (sl., rhizobium) refer to the soil bacteria in α- and β-Proteobacteria that can induce root and/or stem nodules on some legumes and a few of non-legumes. In the nodules, rhizobia convert the inert dinitrogen gas (N2) into ammonia (NH3) and supply them as nitrogen nutrient to the host plant. In general, this symbiotic association presents specificity between rhizobial and leguminous species, and most of the rhizobia use lipochitooligosaccharides (LCOs), so called nodulation factor (NF), for cooperating with their host plant to initiate the formation of nodule primordium and to inhibit the plant immunity. Besides NF, effectors secreted by type III secretion system (T3SS), exopolysaccharides, and many microbe-associated molecular patterns in the rhizobia also play important roles in nodulation and immunity response between rhizobia and legumes. However, the promiscuous hosts like Glycine max and Sophora flavescens can nodulate with various rhizobial species harboring diverse symbiosis genes in different soils, meaning that the nodulation specificity/efficiency might be mainly determined by the host plants and regulated by the soil conditions in a certain cases. Based on previous studies on rhizobial application, we propose a "1+n-N" model to promote the function of symbiotic nitrogen fixation (SNF) in agricultural practice, where "1" refers to appreciate rhizobium; "+n" means the addition of multiple trace elements and PGPR bacteria; and "-N" implies the reduction of chemical nitrogen fertilizer. Finally, open questions in the SNF field are raised to future think deeply and researches.},
}
@article {pmid33300204,
year = {2020},
author = {Akamatsu, A and Nagae, M and Nishimura, Y and Romero Montero, D and Ninomiya, S and Kojima, M and Takebayashi, Y and Sakakibara, H and Kawaguchi, M and Takeda, N},
title = {Endogenous gibberellins affect root nodule symbiosis via transcriptional regulation of NODULE INCEPTION in Lotus japonicus.},
journal = {The Plant journal : for cell and molecular biology},
volume = {},
number = {},
pages = {},
doi = {10.1111/tpj.15128},
pmid = {33300204},
issn = {1365-313X},
abstract = {Legumes and nitrogen-fixing rhizobial bacteria establish root nodule symbiosis, which is orchestrated by several plant hormones. Exogenous addition of biologically active gibberellic acid (GA) is known to inhibit root nodule symbiosis. However, the precise role of GA has not been elucidated because of the trace amounts of these hormones in plants and the multiple functions of GAs. Here, we found that GA signaling acts as a key regulator in a long-distance negative-feedback system of root nodule symbiosis called autoregulation of nodulation (AON). GA biosynthesis is activated during nodule formation in and around the nodule vascular bundles, and bioactive GAs accumulate in the nodule. In addition, GA signaling induces expression of the symbiotic transcription factor NODULE INCEPTION (NIN) via a cis-acting region on the NIN promoter. Mutants with deletions of this cis-acting region have increased susceptibility to rhizobial infection and reduced GA-induced CLE-RS1 and CLE-RS2 expression, suggesting that the inhibitory effect of GAs occurs through AON. This is supported by the GA-insensitive phenotypes of an AON-defective mutant of HYPERNODULATION ABERRANT ROOT FORMATION1 (HAR1), and a reciprocal grafting experiment. Thus, endogenous GAs induce NIN expression via its GA-responsive cis-acting region, then the GA-induced NIN activates the AON system to regulate nodule formation.},
}
@article {pmid33299183,
year = {2020},
author = {Dong, W and Zhu, Y and Chang, H and Wang, C and Yang, J and Shi, J and Gao, J and Yang, W and Lan, L and Wang, Y and Zhang, X and Dai, H and Miao, Y and Xu, L and He, Z and Song, C and Wu, S and Wang, D and Yu, N and Wang, E},
title = {An SHR-SCR module specifies legume cortical cell fate to enable nodulation.},
journal = {Nature},
volume = {},
number = {},
pages = {},
pmid = {33299183},
issn = {1476-4687},
abstract = {Legumes, unlike other plants, have the ability to establish symbiosis with nitrogen-fixing rhizobia. It has been theorized that a unique property of legume root cortical cells enabled the initial establishment of rhizobial symbiosis1-3. Here we show that a SHORTROOT-SCARECROW (SHR-SCR) stem cell program in cortical cells of the legume Medicago truncatula specifies their distinct fate. Regulatory elements drive the cortical expression of SCR, and stele-expressed SHR protein accumulates in cortical cells of M. truncatula but not Arabidopsis thaliana. The cortical SHR-SCR network is conserved across legume species, responds to rhizobial signals, and initiates legume-specific cortical cell division for de novo nodule organogenesis and accommodation of rhizobia. Ectopic activation of SHR and SCR in legumes is sufficient to induce root cortical cell division. Our work suggests that acquisition of the cortical SHR-SCR module enabled cell division coupled to rhizobial infection in legumes. We propose that this event was central to the evolution of rhizobial endosymbiosis.},
}
@article {pmid33299088,
year = {2020},
author = {Malard, F and Dore, J and Gaugler, B and Mohty, M},
title = {Introduction to host microbiome symbiosis in health and disease.},
journal = {Mucosal immunology},
volume = {},
number = {},
pages = {},
pmid = {33299088},
issn = {1935-3456},
abstract = {Humans share a core intestinal microbiome and yet human microbiome differs by genes, species, enterotypes (ecology), and gene count (microbial diversity). Achievement of microbiota metagenomic analysis has revealed that the microbiome gene count is a key stratifier of health in several immune disorders and clinical conditions. We review here the progress of the metagenomic pipeline analysis, and how this has allowed us to define the host-microbe symbiosis associated with a healthy status. The link between host-microbe symbiosis disruption, the so-called dysbiosis and chronic diseases or iatrogenic conditions is highlighted. Finally, opportunities to use microbiota modulation, with specific nutrients and/or live microbes, as a target for personalized nutrition and therapy for the maintenance, preservation, or restoration of host-microbe symbiosis are discussed.},
}
@article {pmid33297962,
year = {2020},
author = {Granado-Rodríguez, S and Bolaños, L and Reguera, M},
title = {MtNIP5;1, a novel Medicago truncatula boron diffusion facilitator induced under deficiency.},
journal = {BMC plant biology},
volume = {20},
number = {1},
pages = {552},
pmid = {33297962},
issn = {1471-2229},
abstract = {BACKGROUND: Legumes comprise important crops that offer major agronomic benefits, including the capacity of establishing symbiosis with rhizobia, fixing atmospheric N2. It has been proven that legumes are particularly susceptible to boron (B) stress, which leads to important yield penalties. Boron (B) deficiency or toxicity in plants causes the inhibition of growth and an altered development. Under such conditions, the participation of two distinct protein families (the major intrinsic protein family MIP and the Boron transporter family BOR) is required to minimize detrimental effects caused by B stress. However, in legumes, little is known about the transport mechanisms responsible for B uptake and distribution, especially under deficiency.
RESULTS: A Medicago truncatula protein, MtNIP5;1 (Medtr1g097840) (homologous to the Arabidopsis thaliana AtNIP5;1) was identified as a novel legume B transporter involved in B uptake under deficiency. Further analyses revealed that this M. truncatula aquaporin expression was boron-regulated in roots, being induced under deficiency and repressed under toxicity. It localizes at the plasma membrane of root epidermal cells and in nodules, where B plays pivotal roles in symbiosis. Furthermore, the partial complementation of the nip5;1-1 A. thaliana mutant phenotype under B deficiency supports a functional role of MtNIP5;1 as a B transporter in this legume model plant.
CONCLUSIONS: The results here presented support a functional role of MtNIP5;1 in B uptake under deficiency and provides new insights into B transport mechanisms in legume species.},
}
@article {pmid33297950,
year = {2020},
author = {Bos, N and Guimaraes, L and Palenzuela, R and Renelies-Hamilton, J and Maccario, L and Silue, SK and Koné, N'A and Poulsen, M},
title = {You don't have the guts: a diverse set of fungi survive passage through Macrotermes bellicosus termite guts.},
journal = {BMC evolutionary biology},
volume = {20},
number = {1},
pages = {163},
pmid = {33297950},
issn = {1471-2148},
support = {771349//H2020 European Research Council/ ; VKR10101//Villum Fonden/ ; },
abstract = {BACKGROUND: Monoculture farming poses significant disease challenges, but fungus-farming termites are able to successfully keep their monoculture crop free from contamination by other fungi. It has been hypothesised that obligate gut passage of all plant substrate used to manure the fungal symbiont is key to accomplish this. Here we refute this hypothesis in the fungus-farming termite species Macrotermes bellicosus.
RESULTS: We first used ITS amplicon sequencing to show that plant substrate foraged on by termite workers harbour diverse fungal communities, which potentially could challenge the farming symbiosis. Subsequently, we cultivated fungi from dissected sections of termite guts to show that fungal diversity does not decrease during gut passage. Therefore, we investigated if healthy combs harboured these undesirable fungal genera, and whether the presence of workers affected fungal diversity within combs. Removal of workers led to a surge in fungal diversity in combs, implying that termite defences must be responsible for the near-complete absence of other fungi in functioning termite gardens.
CONCLUSIONS: The rapid proliferation of some of these fungi when colonies are compromised indicates that some antagonists successfully employ a sit-and-wait strategy that allows them to remain dormant until conditions are favourable. Although this strategy requires potentially many years of waiting, it prevents these fungi from engaging in an evolutionary arms race with the termite host, which employs a series of complementary behavioural and chemical defences that may prove insurmountable.},
}
@article {pmid33297293,
year = {2020},
author = {Sontowski, R and Gerth, M and Richter, S and Gruppe, A and Schlegel, M and van Dam, NM and Bleidorn, C},
title = {Infection Patterns and Fitness Effects of Rickettsia and Sodalis Symbionts in the Green Lacewing Chrysoperla carnea.},
journal = {Insects},
volume = {11},
number = {12},
pages = {},
pmid = {33297293},
issn = {2075-4450},
support = {-//Georg-August-Universität Göttingen/ ; },
abstract = {Endosymbionts are widely distributed in insects and can strongly affect their host ecology. The common green lacewing (Chrysoperla carnea) is a neuropteran insect which is widely used in biological pest control. However, their endosymbionts and their interactions with their hosts have not been very well studied. Therefore, we screened for endosymbionts in natural and laboratory populations of Ch. carnea using diagnostic PCR amplicons. We found the endosymbiont Rickettsia to be very common in all screened natural and laboratory populations, while a hitherto uncharacterized Sodalis strain was found only in laboratory populations. By establishing lacewing lines with no, single or co-infections of Sodalis and Rickettsia, we found a high vertical transmission rate for both endosymbionts (>89%). However, we were only able to estimate these numbers for co-infected lacewings. Sodalis negatively affected the reproductive success in single and co-infected Ch. carnea, while Rickettsia showed no effect. We hypothesize that the fitness costs accrued by Sodalis infections might be more tolerable in the laboratory than in natural populations, as the latter are also prone to fluctuating environmental conditions and natural enemies. The economic and ecological importance of lacewings in biological pest control warrants a more profound understanding of its biology, which might be influenced by symbionts.},
}
@article {pmid33296393,
year = {2020},
author = {Słowiński, J and Surmik, D and Duda, P and Zatoń, M},
title = {Assessment of serpulid-hydroid association through the Jurassic: A case study from the Polish Basin.},
journal = {PloS one},
volume = {15},
number = {12},
pages = {e0242924},
pmid = {33296393},
issn = {1932-6203},
abstract = {The coexistence of sessile, tube-dwelling polychaetes (serpulids) and hydroids, has been investigated. Serpulid tubes bearing traces after hydroids are derived from different stratigraphic intervals spanning the Middle and Upper Jurassic, the rocks of which represent the diverse paleoenvironments of the Polish Basin. Although fossil colonial hydroids classified under the species Protulophila gestroi are a commonly occurring symbiont of these polychaetes during the Late Cretaceous and Cenozoic, they seem to be significantly less frequent during the Jurassic and limited to specific paleoenvironments. The hydroids described here are represented by traces after a thin stolonal network with elongated polyp chambers that open to the outer polychaete tube's surface with small, more or less subcircular apertures. Small chimney-like bulges around openings are an effect of the incorporation of the organism by in vivo embedment (bioclaustration) within the outer layers of the calcareous tube of the serpulid host. Considering the rich collection of well-preserved serpulid tubes (>3000 specimens), the frequency of bioclaustrated hydroids is very low, with an infestation percentage of only 0.6% (20 cases). It has been noticed that only specimens of the genus Propomatoceros from the Upper Bajocian, Lower Bathonian, Middle Bathonian, and Callovian have been found infested. However, the majority of bioclaustrated hydroids (17 cases) have been recorded in the Middle Bathonian serpulid species Propomatoceros lumbricalis coming from a single sampled site. Representatives of other genera are not affected, which is congruent with previous reports indicating that Protulophila gestroi was strongly selective in the choice of its host. A presumably commensal relationship is compared with the recent symbiosis between the hydroids of the genus Proboscidactyla and certain genera of sabellid polychaetes.},
}
@article {pmid33295865,
year = {2020},
author = {Lefoulon, E and Clark, T and Guerrero, R and Cañizales, I and Cardenas-Callirgos, JM and Junker, K and Vallarino-Lhermitte, N and Makepeace, BL and Darby, AC and Foster, JM and Martin, C and Slatko, BE},
title = {Diminutive, degraded but dissimilar: Wolbachia genomes from filarial nematodes do not conform to a single paradigm.},
journal = {Microbial genomics},
volume = {6},
number = {12},
pages = {},
doi = {10.1099/mgen.0.000487},
pmid = {33295865},
issn = {2057-5858},
abstract = {Wolbachia are alpha-proteobacteria symbionts infecting a large range of arthropod species and two different families of nematodes. Interestingly, these endosymbionts are able to induce diverse phenotypes in their hosts: they are reproductive parasites within many arthropods, nutritional mutualists within some insects and obligate mutualists within their filarial nematode hosts. Defining Wolbachia 'species' is controversial and so they are commonly classified into 17 different phylogenetic lineages, termed supergroups, named A-F, H-Q and S. However, available genomic data remain limited and not representative of the full Wolbachia diversity; indeed, of the 24 complete genomes and 55 draft genomes of Wolbachia available to date, 84 % belong to supergroups A and B, exclusively composed of Wolbachia from arthropods. For the current study, we took advantage of a recently developed DNA-enrichment method to produce four complete genomes and two draft genomes of Wolbachia from filarial nematodes. Two complete genomes, wCtub and wDcau, are the smallest Wolbachia genomes sequenced to date (863 988 bp and 863 427 bp, respectively), as well as the first genomes representing supergroup J. These genomes confirm the validity of this supergroup, a controversial clade due to weaknesses of the multilocus sequence typing approach. We also produced the first draft Wolbachia genome from a supergroup F filarial nematode representative (wMhie), two genomes from supergroup D (wLsig and wLbra) and the complete genome of wDimm from supergroup C. Our new data confirm the paradigm of smaller Wolbachia genomes from filarial nematodes containing low levels of transposable elements and the absence of intact bacteriophage sequences, unlike many Wolbachia from arthropods, where both are more abundant. However, we observe differences among the Wolbachia genomes from filarial nematodes: no global co-evolutionary pattern, strong synteny between supergroup C and supergroup J Wolbachia, and more transposable elements observed in supergroup D Wolbachia compared to the other supergroups. Metabolic pathway analysis indicates several highly conserved pathways (haem and nucleotide biosynthesis, for example) as opposed to more variable pathways, such as vitamin B biosynthesis, which might be specific to certain host-symbiont associations. Overall, there appears to be no single Wolbachia-filarial nematode pattern of co-evolution or symbiotic relationship.},
}
@article {pmid33295132,
year = {2020},
author = {Farnelid, H and Turk-Kubo, K and Zehr, JP},
title = {Cell sorting reveals few novel prokaryote and photosynthetic picoeukaryote associations in the oligotrophic ocean.},
journal = {Environmental microbiology},
volume = {},
number = {},
pages = {},
doi = {10.1111/1462-2920.15351},
pmid = {33295132},
issn = {1462-2920},
support = {329108//Simons Foundation/ ; 637-2013-7502//Vetenskapsrådet/ ; },
abstract = {Close associations between single-celled marine organisms can have a central role in biogeochemical processes and are of great interest for understanding the evolution of organisms. The global significance of such associations raises the question of whether unidentified associations are yet to be discovered. In this study, fluorescence-activated cell sorted photosynthetic picoeukayote (PPE) populations and single cells were analysed by sequencing of 16S rRNA genes in the oligotrophic North Pacific Subtropical Gyre. Samples were collected during two cruises, spanning depths near the deep chlorophyll maximum, where the abundance of PPEs was highest. The association between the widespread and significant nitrogen (N2)-fixing cyanobacterium, UCYN-A and its prymnesiophyte host was prevalent in both population and single-cell sorts. Several bacterial sequences, affiliating with previously described symbiotic taxa were detected but their detection was rare and not well replicated, precluding identification of novel tightly linked species-specific associations. Similarly, no enrichment of dominant seawater taxa such as Prochlorococcus, SAR11 or Synechococcus was observed suggesting that these were not systematically ingested by the PPE in this study. The results indicate that apart from the UCYN-A symbiosis, similar tight species-specific associations with PPEs are unusual in the oligotrophic ocean.},
}
@article {pmid33290681,
year = {2020},
author = {Bedgood, SA and Mastroni, SE and Bracken, MES},
title = {Flexibility of nutritional strategies within a mutualism: food availability affects algal symbiont productivity in two congeneric sea anemone species.},
journal = {Proceedings. Biological sciences},
volume = {287},
number = {1940},
pages = {20201860},
pmid = {33290681},
issn = {1471-2954},
abstract = {Mutualistic symbioses are common, especially in nutrient-poor environments where an association between hosts and symbionts can allow the symbiotic partners to persist and collectively out-compete non-symbiotic species. Usually these mutualisms are built on an intimate transfer of energy and nutrients (e.g. carbon and nitrogen) between host and symbiont. However, resource availability is not consistent, and the benefit of the symbiotic association can depend on the availability of resources to mutualists. We manipulated the diets of two temperate sea anemone species in the genus Anthopleura in the field and recorded the responses of sea anemones and algal symbionts in the family Symbiodiniaceae to our treatments. Algal symbiont density, symbiont volume and photosynthetic efficiency of symbionts responded to changes in sea anemone diet, but the responses depended on the species of sea anemone. We suggest that temperate sea anemones and their symbionts can respond to changes in anemone diet, modifying the balance between heterotrophy and autotrophy in the symbiosis. Our data support the hypothesis that symbionts are upregulated or downregulated based on food availability, allowing for a flexible nutritional strategy based on external resources.},
}
@article {pmid33288750,
year = {2020},
author = {Brooker, RM and Casey, JM and Cowan, ZL and Sih, TL and Dixson, DL and Manica, A and Feeney, WE},
title = {Domestication via the commensal pathway in a fish-invertebrate mutualism.},
journal = {Nature communications},
volume = {11},
number = {1},
pages = {6253},
pmid = {33288750},
issn = {2041-1723},
mesh = {Animals ; Belize ; Biodiversity ; Coral Reefs ; *Domestication ; *Ecosystem ; Fishes/classification/*physiology ; Geography ; Invertebrates/classification/*physiology ; Microalgae/classification/physiology ; Symbiosis/*physiology ; },
abstract = {Domesticator-domesticate relationships are specialized mutualisms where one species provides multigenerational support to another in exchange for a resource or service, and through which both partners gain an advantage over individuals outside the relationship. While this ecological innovation has profoundly reshaped the world's landscapes and biodiversity, the ecological circumstances that facilitate domestication remain uncertain. Here, we show that longfin damselfish (Stegastes diencaeus) aggressively defend algae farms on which they feed, and this protective refuge selects a domesticator-domesticate relationship with planktonic mysid shrimps (Mysidium integrum). Mysids passively excrete nutrients onto farms, which is associated with enriched algal composition, and damselfish that host mysids exhibit better body condition compared to those without. Our results suggest that the refuge damselfish create as a byproduct of algal tending and the mutual habituation that damselfish and mysids exhibit towards one another were instrumental in subsequent mysid domestication. These results are consistent with domestication via the commensal pathway, by which many common examples of animal domestication are hypothesized to have evolved.},
}
@article {pmid33287282,
year = {2020},
author = {Zorin, EA and Afonin, AM and Kulaeva, OA and Gribchenko, ES and Shtark, OY and Zhukov, VA},
title = {Transcriptome Analysis of Alternative Splicing Events Induced by Arbuscular Mycorrhizal Fungi (Rhizophagus irregularis) in Pea (Pisum sativum L.) Roots.},
journal = {Plants (Basel, Switzerland)},
volume = {9},
number = {12},
pages = {},
pmid = {33287282},
issn = {2223-7747},
support = {19-316-90058//Russian Foundation for Basic Research/ ; 20-04-01136//Russian Foundation for Basic Research/ ; },
abstract = {Alternative splicing (AS), a process that enables formation of different mRNA isoforms due to alternative ways of pre-mRNA processing, is one of the mechanisms for fine-tuning gene expression. Currently, the role of AS in symbioses formed by plants with soil microorganisms is not fully understood. In this work, a comprehensive analysis of the transcriptome of garden pea (Pisum sativum L.) roots in symbiosis with arbuscular mycorrhiza was performed using RNAseq and following bioinformatic analysis. AS profiles of mycorrhizal and control roots were highly similar, intron retention accounting for a large proportion of the observed AS types (67%). Using three different tools (SUPPA2, DRIMSeq and IsoformSwitchAnalyzeR), eight genes with AS events specific for mycorrhizal roots of pea were identified, among which four were annotated as encoding an apoptosis inhibitor protein, a serine/threonine-protein kinase, a dehydrodolichyl diphosphate synthase, and a pre-mRNA-splicing factor ATP-dependent RNA helicase DEAH1. In pea mycorrhizal roots, the isoforms of these four genes with preliminary stop codons leading to a truncated ORFs were up-regulated. Interestingly, two of these four genes demonstrating mycorrhiza-specific AS are related to the process of splicing, thus forming parts of the feedback loops involved in fine-tuning of gene expression during mycorrhization.},
}
@article {pmid33283865,
year = {2020},
author = {Fagorzi, C and Ilie, A and Decorosi, F and Cangioli, L and Viti, C and Mengoni, A and diCenzo, GC},
title = {Symbiotic and Nonsymbiotic Members of the Genus Ensifer (syn. Sinorhizobium) Are Separated into Two Clades Based on Comparative Genomics and High-Throughput Phenotyping.},
journal = {Genome biology and evolution},
volume = {12},
number = {12},
pages = {2521-2534},
pmid = {33283865},
issn = {1759-6653},
abstract = {Rhizobium-legume symbioses serve as paradigmatic examples for the study of mutualism evolution. The genus Ensifer (syn. Sinorhizobium) contains diverse plant-associated bacteria, a subset of which can fix nitrogen in symbiosis with legumes. To gain insights into the evolution of symbiotic nitrogen fixation (SNF), and interkingdom mutualisms more generally, we performed extensive phenotypic, genomic, and phylogenetic analyses of the genus Ensifer. The data suggest that SNF likely emerged several times within the genus Ensifer through independent horizontal gene transfer events. Yet, the majority (105 of 106) of the Ensifer strains with the nodABC and nifHDK nodulation and nitrogen fixation genes were found within a single, monophyletic clade. Comparative genomics highlighted several differences between the "symbiotic" and "nonsymbiotic" clades, including divergences in their pangenome content. Additionally, strains of the symbiotic clade carried 325 fewer genes, on average, and appeared to have fewer rRNA operons than strains of the nonsymbiotic clade. Initial characterization of a subset of ten Ensifer strains identified several putative phenotypic differences between the clades. Tested strains of the nonsymbiotic clade could catabolize 25% more carbon sources, on average, than strains of the symbiotic clade, and they were better able to grow in LB medium and tolerate alkaline conditions. On the other hand, the tested strains of the symbiotic clade were better able to tolerate heat stress and acidic conditions. We suggest that these data support the division of the genus Ensifer into two main subgroups, as well as the hypothesis that pre-existing genetic features are required to facilitate the evolution of SNF in bacteria.},
}
@article {pmid33281845,
year = {2020},
author = {Feng, Z and Liu, X and Zhu, H and Yao, Q},
title = {Responses of Arbuscular Mycorrhizal Symbiosis to Abiotic Stress: A Lipid-Centric Perspective.},
journal = {Frontiers in plant science},
volume = {11},
number = {},
pages = {578919},
pmid = {33281845},
issn = {1664-462X},
abstract = {Arbuscular mycorrhizal (AM) fungi are one of the most important soil microbial resources that help host plants cope with various abiotic stresses. Although a tremendous number of studies have revealed the responses of AM fungi to abiotic stress and their beneficial effects transferred to host plants, little work has focused on the role of lipid metabolism in AM fungi under abiotic stress conditions. AM fungi contain a large amount of lipids in their biomass, including phospholipids (PLs) in their hyphal membranes and neutral lipids (NLs) in their storage structures (e.g., vesicles and spores). Recently, lipid transfer from plants to AM fungi has been suggested to be indispensable for the establishment of AM symbiosis, and extraradical hyphae are capable of directly taking up lipids from the environment. This experimental evidence highlights the importance of lipids in AM symbiosis. Moreover, abiotic stress reduces lipid transfer to AM fungi and promotes arbuscule collapse as well as the hydrolysis and conversion of PLs to NLs in collapsed arbuscules. Overall, this knowledge encourages us to rethink the responses of AM symbiosis to abiotic stress from a lipid-centric perspective. The present review provides current and comprehensive knowledge on lipid metabolism in AM fungi, especially in response to various abiotic stresses. A regulatory role of abscisic acid (ABA), which is considered a "stress hormone," in lipid metabolism and in the resulting consequences is also proposed.},
}
@article {pmid33281793,
year = {2020},
author = {Miao, YH and Xiao, JH and Huang, DW},
title = {Distribution and Evolution of the Bacteriophage WO and Its Antagonism With Wolbachia.},
journal = {Frontiers in microbiology},
volume = {11},
number = {},
pages = {595629},
pmid = {33281793},
issn = {1664-302X},
abstract = {The symbiosis system comprising eukaryotic hosts, intracellular bacterium Wolbachia, and temperate bacteriophages WO is widely spread through nearly half the number of arthropod species. The relationships between the three components of the system are extremely intricate. Even though the bacteriophage WO can have diverse influences on the ecology and evolution of Wolbachia, little is known about the distribution and evolution of the phages. To the best of our knowledge, this study is the first to report that in infected fig wasps (Ceratosolen solmsi, Kradibia gibbosae, and Wiebesia pumilae), the genomes of all the Wolbachia strains had only one cryptic WO prophage, which contained defects in the genomic structural modules. This phenomenon was contrary to the widely accepted understanding that Wolbachia with cryptic prophages usually possesses at least one intact WO prophage consisting of gene sequences of the head, baseplate, and tail modules, through which the prophage could form intact virions. In addition to the genetic structure features, the phylogenetic relationships of WO and Wolbachia also revealed that bacteriophage WO can horizontally spread among a certain genus or a group of insect hosts, nearly free from the restriction of the affiliation of Wolbachia. Combined with the vertical transmission along with Wolbachia, the wide spread of WO phages can be explained. Furthermore, the gender preference and functional module preference for transcriptional activity of the genes in cryptic WOs implied the antagonized coevolutionary pattern between WO prophages and their Wolbachia hosts.},
}
@article {pmid33281765,
year = {2020},
author = {Rahaman, MS and Siraj, MA and Sultana, S and Seidel, V and Islam, MA},
title = {Molecular Phylogenetics and Biological Potential of Fungal Endophytes From Plants of the Sundarbans Mangrove.},
journal = {Frontiers in microbiology},
volume = {11},
number = {},
pages = {570855},
pmid = {33281765},
issn = {1664-302X},
abstract = {The Sundarbans forest in Bangladesh is the world's largest mangrove. It is a unique ecosystem where living organisms face extreme challenges to compete for survival. Such competition results in the production of bioactive molecules which are useful for agriculture and human health. In this study, eighty fungal endophytes from nine mangrove plants growing in a region, as yet unexplored, of the Sundarbans were isolated by surface sterilisation and pure culture techniques. Among the eighty isolates subjected to a preliminary antimicrobial screening using an agar plug diffusion assay, only fifteen showed some promising activity. These were subsequently identified by polymerase chain reaction of their ITS gene. Extracts prepared from the identified isolates were screened for antimicrobial, antioxidant, cytotoxic and α-glucosidase inhibitory activities. Their total polyphenol and flavonoid content and their FRAP value were also determined. All endophytes are reported for the first time in the plants under investigation.},
}
@article {pmid33281366,
year = {2020},
author = {Shinde, DB and Singhvi, S and Koratkar, SS and Saroj, SD},
title = {Isolation and characterization of Escherichia coli serotype O157:H7 and other verotoxin-producing E. coli in healthy Indian cattle.},
journal = {Veterinary world},
volume = {13},
number = {10},
pages = {2269-2274},
pmid = {33281366},
issn = {0972-8988},
abstract = {Background and Aim: Cattle are the main reservoir of Escherichia coli O157:H7 and other verotoxigenic E. coli (VTEC); therefore, there is an increased risk of infection to humans by either direct or indirect mode of transmissions. However, the prevalence of E. coli O157:H7 in the healthy cattle population of India is yet to be ascertained. This study aimed to screen the dairy cattle in and around Pune, Maharashtra, India, for verotoxin-producing E. coli O157:H7.
Materials and Methods: A total of 257 rectal swabs were collected from 15 different organized and unorganized dairy farms of Pune during the period, January-March 2015. The screening involved enrichment in EC broth followed by differential identification on MacConkey sorbitol agar. The presumptive positive isolates were further confirmed by multiplex polymerase chain reaction (PCR) using primers specific to rfbE (O157), fliC (H7), VT1 (MK1), and VT2 (MK2). Vero-toxicity and antibiotic sensitivity were examined in PCR confirmed isolates.
Results: Out of the 257 samples analyzed, 1.9% (2/105) were positive for O157:H7 and 39% (41/105) were positive for VTEC. Two PCR confirmed positive O157:H7 strains and two randomly selected PCR-positive VT strains exhibited in vitro cytopathic effect on Vero cells on day-7 post-inoculation. Antibiotic sensitivity profiling of O157:H7 strains exhibited resistance against penicillin G, kanamycin, ampicillin, tetracycline, gentamycin, cefotaxime, streptomycin, and piperacillin.
Conclusion: These findings reveal the presence of pathogenic E. coli O157:H7 in the healthy cattle of Pune; in a situation, wherein regular surveillance for O157:H7 is not a norm. Therefore, the findings presented herein warrant routine surveillance and public awareness to prevent the transfer of such pathogens and manage health risks to the public.},
}
@article {pmid33279568,
year = {2020},
author = {Kowallik, KV and Martin, WF},
title = {The origin of symbiogenesis: An annotated English translation of Mereschkowsky's 1910 paper on the theory of two plasma lineages.},
journal = {Bio Systems},
volume = {199},
number = {},
pages = {104281},
doi = {10.1016/j.biosystems.2020.104281},
pmid = {33279568},
issn = {1872-8324},
abstract = {In 1910, the Russian biologist Konstantin Sergejewitch Mereschkowsky (Константин Сергеевич Мережковский, in standard transliterations also written as Konstantin Sergeevič Merežkovskij and Konstantin Sergeevich Merezhkovsky) published a notable synthesis of observations and inferences concerning the origin of life and the origin of nucleated cells. His theory was based on physiology and leaned heavily upon the premise that thermophilic autotrophs were ancient. The ancestors of plants and animals were inferred as ancestrally mesophilic anucleate heterotrophs (Monera) that became complex and diverse through endosymbiosis. He placed a phylogenetic root in the tree of life among anaerobic autotrophic bacteria that lack chlorophyll. His higher level classification of all microbes and macrobes in the living world was based upon the presence or absence of past endosymbiotic events. The paper's primary aim was to demonstrate that all life forms descend from two fundamentally distinct organismal lineages, called mykoplasma and amoeboplasma, whose very nature was so different that, in his view, they could only have arisen independently of one another and at different times during Earth history. The mykoplasma arose at a time when the young Earth was still hot, it later gave rise to cyanobacteria, which in turn gave rise to plastids. The product of the second origin of life, the amoeboplasma, arose after the Earth had cooled and autotrophs had generated substrates for heterotrophic growth. Lineage diversification of that second plasma brought forth, via serial endosymbioses, animals (one symbiosis) and then plants (two symbioses, the second being the plastid). The paper was published in German, rendering it inaccessible to many interested scholars. Here we translate the 1910 paper in full and briefly provide some context.},
}
@article {pmid33278908,
year = {2020},
author = {Kirkpatrick, AW and Hamilton, DR and McKee, JL and MacDonald, B and Pelosi, P and Ball, CG and Roberts, D and McBeth, PB and Cocolini, F and Ansaloni, L and Peireira, B and Sugrue, M and Campbell, MR and Kimball, EJ and Malbrain, MLNG and Roberts, D},
title = {Do we have the guts to go? The abdominal compartment, intra-abdominal hypertension, the human microbiome and exploration class space missions.},
journal = {Canadian journal of surgery. Journal canadien de chirurgie},
volume = {63},
number = {6},
pages = {E581-E593},
pmid = {33278908},
issn = {1488-2310},
abstract = {Humans are destined to explore space, yet critical illness and injury may be catastrophically limiting for extraterrestrial travel. Humans are superorganisms living in symbiosis with their microbiomes, whose genetic diversity dwarfs that of humans. Symbiosis is critical and imbalances are associated with disease, occurring within hours of serious illness and injury. There are many characteristics of space flight that negatively influence the microbiome, especially deep space itself, with its increased radiation and absence of gravity. Prolonged weightlessness causes many physiologic changes that are detrimental; some resemble aging and will adversely affect the ability to tolerate critical illness or injury and subsequent treatment. Critical illness-induced intra-abdominal hypertension (IAH) may induce malperfusion of both the viscera and microbiome, with potentially catastrophic effects. Evidence from animal models confirms profound IAH effects on the gut, namely ischemia and disruption of barrier function, mechanistically linking IAH to resultant organ dysfunction. Therefore, a pathologic dysbiome, space-induced immune dysfunction and a diminished cardiorespiratory reserve with exacerbated susceptibility to IAH, imply that a space-deconditioned astronaut will be vulnerable to IAH-induced gut malperfusion. This sets the stage for severe gut ischemia and massive biomediator generation in an astronaut with reduced cardiorespiratory/immunological capacity. Fortunately, experiments in weightless analogue environments suggest that IAH may be ameliorated by conformational abdominal wall changes and a resetting of thoracoabdominal mechanics. Thus, review of the interactions of physiologic changes with prolonged weightlessness and IAH is required to identify appropriate questions for planning exploration class space surgical care.},
}
@article {pmid33277272,
year = {2020},
author = {Zou, Q and Zhou, Y and Cheng, G and Peng, Y and Luo, S and Wu, H and Yan, C and Li, X and He, D},
title = {Antioxidant ability of glutaredoxins and their role in symbiotic nitrogen fixation in Rhizobium leguminosarum bv. viciae 3841.},
journal = {Applied and environmental microbiology},
volume = {},
number = {},
pages = {},
doi = {10.1128/AEM.01956-20},
pmid = {33277272},
issn = {1098-5336},
abstract = {Glutaredoxins (Grx) are redoxin family proteins that reduce disulfides and mixed disulfides between glutathione and proteins. Rhizobium leguminosarum bv. Viciae 3841 contains three genes coding for glutaredoxins: RL4289 (grxA) codes for a dithiolic glutaredoxin, RL2615 (grxB) codes for a monothiol glutaredoxin, while RL4261 (grxC) codes for a glutaredoxin-like NrdH protein. We generated mutants interrupted in one, two, or three glutaredoxin genes. These mutants had no obvious differences in growth phenotypes from the wild type RL3841. However, while a mutant of grxC did not affect the antioxidant or symbiotic capacities of R. leguminosarum, grxA-derived or grxB mutants decreased antioxidant and nitrogen fixation capacities. Furthermore, grxA mutants were severely impaired in rhizosphere colonization, and formed smaller nodules with defects of bacteroid differentiation, whereas nodules induced by grxB mutants contained abnormally thick cortices and prematurely senescent bacteroids. The grx triple mutant had the greatest defect in antioxidant and symbiotic capacities of R. leguminosarum and quantitative proteomics revealed it had 56 up-regulated and 81 down-regulated proteins relative to wildtype. Of these proteins, twenty-eight are involved in transporter activity, twenty are related to stress response and virulence, and sixteen are involved in amino acid metabolism. Overall, R. leguminosarum glutaredoxins behave as antioxidant proteins mediating root nodule symbiosis.IMPORTANCE Glutaredoxin catalyzes glutathionylation/deglutathionylation reactions, protects SH-groups from oxidation and restores functionally active thiols. Three glutaredoxins exist in R. leguminosarum and their properties were investigated in free-living bacteria and during nitrogen-fixing symbiosis. All the glutaredoxins were necessary for oxidative stress defense. Dithiol GrxA affects nodulation and nitrogen fixation of bacteroids by altering deglutathionylation reactions, monothiol GrxB is involved in symbiotic nitrogen fixation by regulating Fe-S cluster biogenesis, and GrxC may participate in symbiosis by an unknown mechanism. Proteome analysis provides clues to explain the differences between the grx triple mutant and wild-type nodules.},
}
@article {pmid33277267,
year = {2020},
author = {Elston, KM and Perreau, J and Maeda, GP and Moran, NA and Barrick, JE},
title = {Engineering a Culturable Serratia symbiotica Strain for Aphid Paratransgenesis.},
journal = {Applied and environmental microbiology},
volume = {},
number = {},
pages = {},
doi = {10.1128/AEM.02245-20},
pmid = {33277267},
issn = {1098-5336},
abstract = {Aphids are global agricultural pests and important models for bacterial symbiosis. To date, none of the native symbionts of aphids have been genetically manipulated, which limits our understanding of how they interact with their hosts. Serratia symbiotica CWBI-2.3T is a culturable, gut-associated bacterium isolated from the black bean aphid. Closely related Serratia symbiotica strains are facultative aphid endosymbionts that are vertically transmitted from mother to offspring during embryogenesis. We demonstrate that CWBI-2.3T can be genetically engineered using a variety of techniques, plasmids, and gene expression parts. Then, we use fluorescent protein expression to track the dynamics with which CWBI-2.3T colonizes the guts of multiple aphid species, and we measure how this bacterium affects aphid fitness. Finally, we show that we can induce heterologous gene expression from engineered CWBI-2.3T in living aphids. These results inform the development of CWBI-2.3T for aphid paratransgenesis, which could be used to study aphid biology and enable future agricultural technologies.IMPORTANCE Insects have remarkably diverse and integral roles in global ecosystems. Many harbor symbiotic bacteria, but very few of these bacteria have been genetically engineered. Aphids are major agricultural pests and an important model system for the study of symbiosis. This work describes methods for engineering a culturable aphid symbiont, Serratia symbiotica CWBI-2.3T These approaches and genetic tools could be used in the future to implement new paradigms for the biological study and control of aphids.},
}
@article {pmid33274397,
year = {2020},
author = {Bien, T and Hambleton, EA and Dreisewerd, K and Soltwisch, J},
title = {Molecular insights into symbiosis-mapping sterols in a marine flatworm-algae-system using high spatial resolution MALDI-2-MS imaging with ion mobility separation.},
journal = {Analytical and bioanalytical chemistry},
volume = {},
number = {},
pages = {},
doi = {10.1007/s00216-020-03070-0},
pmid = {33274397},
issn = {1618-2650},
support = {Drei2/018/17//Interdisciplinary Center for Clinical Research, Münster, Germany/ ; SO976/5-1, project number 400912714//Deutsche Forschungsgemeinschaft/ ; },
abstract = {Waminoa sp. acoel flatworms hosting Symbiodiniaceae and the related Amphidinium dinoflagellate algae are an interesting model system for symbiosis in marine environments. While the host provides a microhabitat and safety, the algae power the system by photosynthesis and supply the worm with nutrients. Among these nutrients are sterols, including cholesterol and numerous phytosterols. While it is widely accepted that these compounds are produced by the symbiotic dinoflagellates, their transfer to and fate within the sterol-auxotrophic Waminoa worm host as well as their role in its metabolism are unknown. Here we used matrix-assisted laser desorption ionization (MALDI) mass spectrometry imaging combined with laser-induced post-ionization and trapped ion mobility spectrometry (MALDI-2-TIMS-MSI) to map the spatial distribution of over 30 different sterol species in sections of the symbiotic system. The use of laser post-ionization crucially increased ion yields and allowed the recording of images with a pixel size of 5 μm. Trapped ion mobility spectrometry (TIMS) helped with the tentative assignment of over 30 sterol species. Correlation with anatomical features of the worm, revealed by host-derived phospholipid signals, and the location of the dinoflagellates, revealed by chlorophyll a signal, disclosed peculiar differences in the distribution of different sterol species (e.g. of cholesterol versus stigmasterol) within the receiving host. These findings point to sterol species-specific roles in the metabolism of Waminoa beyond a mere source of energy. They also underline the value of the MALDI-2-TIMS-MSI method to future research in the spatially resolved analysis of sterols.},
}
@article {pmid33272985,
year = {2020},
author = {Ivanova, EV and Bekpergenova, AV and Perunova, NB and Andryuschenko, SV and Bondarenko, TA and Bukharin, OV},
title = {Genome Sequence Data of Lactobacillus ruminis ICIS-540, Isolated from the Intestine of a Healthy Woman.},
journal = {Microbiology resource announcements},
volume = {9},
number = {49},
pages = {},
pmid = {33272985},
issn = {2576-098X},
abstract = {Data on the draft genome sequence of Lactobacillus ruminis ICIS-540 are presented in this report. This Lactobacillus strain was isolated from the human colon as a prospective probiotic candidate. The genome size was 2,397,517 bp (G+C content, 42.7%). Annotation revealed 2,847 coding sequences, including 2,573 proteins.},
}
@article {pmid33272789,
year = {2020},
author = {Muñoz-Benavent, M and Pérez-Cobas, AE and García-Ferris, C and Moya, A and Latorre, A},
title = {Insects' potential: Understanding the functional role of their gut microbiome.},
journal = {Journal of pharmaceutical and biomedical analysis},
volume = {},
number = {},
pages = {113787},
doi = {10.1016/j.jpba.2020.113787},
pmid = {33272789},
issn = {1873-264X},
abstract = {The study of insect-associated microbial communities is a field of great importance in agriculture, principally because of the role insects play as pests. In addition, there is a recent focus on the potential of the insect gut microbiome in areas such as biotechnology, given some microorganisms produce molecules with biotechnological and industrial applications, and also in biomedicine, since some bacteria and fungi are a reservoir of antibiotic resistance genes (ARGs). To date, most studies aiming to characterize the role of the gut microbiome of insects have been based on high-throughput sequencing of the 16S rRNA gene and/or metagenomics. However, recently functional approaches such as metatranscriptomics, metaproteomics and metabolomics have also been employed. Besides providing knowledge about the taxonomic distribution of microbial populations, these techniques also reveal their functional and metabolic capabilities. This information is essential to gain a better understanding of the role played by microbes comprising the microbial communities in their hosts, as well as to indicate their possible exploitation. This review provides an overview of how far we have come in characterizing insect gut functionality through omics, as well as the challenges and future perspectives in this field.},
}
@article {pmid33271360,
year = {2020},
author = {Bridges, CM and Gage, DJ},
title = {Development and application of aerobic, chemically defined media for Dysgonomonas.},
journal = {Anaerobe},
volume = {67},
number = {},
pages = {102302},
doi = {10.1016/j.anaerobe.2020.102302},
pmid = {33271360},
issn = {1095-8274},
abstract = {Members of Dysgonomonas are Gram-stain-negative, non-motile, facultatively anaerobic coccobacilli originally described in relation to their isolation from stool and wounds of human patients (CDC group DF-3). More recently, Dysgonomonas have been found to be widely distributed in terrestrial environments and are particularly enriched in insect systems. Their prevalence in xylophagous insects such as termites and wood-feeding cockroaches, as well as in soil-fed microbial fuel cells, elicit interest in lignocellulose degradation and biofuel production, respectively. Their occurrence in mosquito and fruit fly have implications relating to symbiosis, host immunology and developmental biology. Additionally, their presence in termite, mosquito and nematode present novel opportunities for pest and vector control. Currently, the absolute growth requirements of Dysgonomonas are unknown, and they are commonly cultured under anaerobic conditions on complex media containing blood, peptones, tryptones, and yeast, plant or meat extracts. Restrictive and undefined culturing conditions preclude physiological and genetic studies, and thus further understanding of their metabolic potential. Here we describe the requirements for growth of termite-derived Dysgonomonas isolates and create parallel complex, defined and minimal media that permit vigorous and reliable aerobic growth. Furthermore, we show that these media can be used to easily enrich for Dysgonomonas isolates from densely-colonized and microbially-diverse environmental samples.},
}
@article {pmid33266512,
year = {2020},
author = {Fu, N and Li, J and Wang, M and Ren, L and Luo, Y},
title = {Genes Identification, Molecular Docking and Dynamics Simulation Analysis of Laccases from Amylostereum areolatum Provides Molecular Basis of Laccase Bound to Lignin.},
journal = {International journal of molecular sciences},
volume = {21},
number = {22},
pages = {},
pmid = {33266512},
issn = {1422-0067},
support = {2018YFC1200400//National Key R & D Program of China/ ; 31870642//Chinese National Natural Science Foundation/ ; },
abstract = {An obligate mutualistic relationship exists between the fungus Amylostereum areolatum and woodwasp Sirex noctilio. The fungus digests lignin in the host pine, providing essential nutrients for the growing woodwasp larvae. However, the functional properties of this symbiosis are poorly described. In this study, we identified, cloned, and characterized 14 laccase genes from A. areolatum. These genes encoded proteins of 508 to 529 amino acids and contained three typical copper-oxidase domains, necessary to confer laccase activity. Besides, we performed molecular docking and dynamics simulation of the laccase proteins in complex with lignin compounds (monomers, dimers, trimers, and tetramers). AaLac2, AaLac3, AaLac6, AaLac8, and AaLac10 were found that had low binding energies with all lignin model compounds tested and three of them could maintain stability when binding to these compounds. Among these complexes, amino acid residues ALA, GLN, LEU, PHE, PRO, and SER were commonly present. Our study reveals the molecular basis of A. areolatum laccases interacting with lignin, which is essential for understanding how the fungus provides nutrients to S. noctilio. These findings might also provide guidance for the control of S. noctilio by informing the design of enzyme mutants that could reduce the efficiency of lignin degradation.},
}
@article {pmid33266163,
year = {2020},
author = {Flegar, M and Serdar, M and Londono-Zuluaga, D and Scrivener, K},
title = {Regional Waste Streams as Potential Raw Materials for Immediate Implementation in Cement Production.},
journal = {Materials (Basel, Switzerland)},
volume = {13},
number = {23},
pages = {},
pmid = {33266163},
issn = {1996-1944},
support = {UIP-05-2018-4767//Hrvatska Zaklada za Znanost/ ; IZHRZO_180590/1//Schweizerischer Nationalfonds zur Förderung der Wissenschaftlichen Forschung/ ; },
abstract = {There is an urgent need to apply available technologies to reduce the environmental impact of the construction industry. One of the possible solutions that can be implemented immediately is the industrial symbiosis between the waste-producing industries on the one hand and the cement industry, which consumes enormous amounts of raw materials for its production, on the other. In order for the industry to accelerate the use of these available materials and technologies, the potential of these materials must be disclosed. The present study shows a systematic approach to assess the potential of waste materials, by-products, and other raw materials available in the South East Europe that can be used in cement production. Their evaluation included the analysis of their availability, their chemical and physical properties, their chemical reactivity, and their contribution to the mortar's strength. Based on the results and the analyses carried out, a recommendation for immediate use in the construction sector is given for each of the materials collected.},
}
@article {pmid33264074,
year = {2020},
author = {Haelewaters, D and Kasson, MT},
title = {Animal-associated fungi: Editorial.},
journal = {Mycologia},
volume = {112},
number = {6},
pages = {1045-1047},
doi = {10.1080/00275514.2020.1841469},
pmid = {33264074},
issn = {1557-2536},
abstract = {Of 1882 fungal species described in 2019, only 3.5% were animal-associated. This percentage is representative of the poor understanding we have of this group of fungi, which are ephemeral, sometimes inconspicuous, and difficult to access, while often requiring specialized methods for their study. Following a two-session symposium on animal-associated fungi during the 2019 Annual Meeting of the Mycological Society of America, this special issue presents the work of 61 researchers in 16 countries. Twelve articles cover animal-associated fungi among Ascomycota, Basidiomycota, and Neocallimastigomycota-describing 29 new species, presenting new evolutionary hypotheses, and unearthing new ecological data.},
}
@article {pmid33263889,
year = {2020},
author = {Kloc, M and Uosef, A and Elshawwaf, M and Abdelshafy, AAA and Elsaid, KMK and Kubiak, JZ and Ghobrial, RM},
title = {The Macrophages and Intestinal Symbiosis.},
journal = {Results and problems in cell differentiation},
volume = {69},
number = {},
pages = {605-616},
doi = {10.1007/978-3-030-51849-3_23},
pmid = {33263889},
issn = {0080-1844},
abstract = {The human intestinal tract is inhabited by trillions of microorganisms and houses the largest pool of macrophages in the human body. Being a part of the innate immune system, the macrophages, the professional phagocytes, vigorously respond to the microbial and dietary antigens present in the intestine. Because such a robust immune response poses the danger to the survival of the non-harmful and beneficial gut microbiota, the macrophages developed mechanisms of recognition and hyposensitivity toward the non-harmful/beneficial inhabitants of the gut. We will discuss the evolution and identity of some of these mechanisms in the following chapter.},
}
@article {pmid33263888,
year = {2020},
author = {Keane, JM and Joyce, SA and Gahan, CGM and Hyland, NP and Houston, A},
title = {Microbial Metabolites as Molecular Mediators of Host-Microbe Symbiosis in Colorectal Cancer.},
journal = {Results and problems in cell differentiation},
volume = {69},
number = {},
pages = {581-603},
doi = {10.1007/978-3-030-51849-3_22},
pmid = {33263888},
issn = {0080-1844},
abstract = {The symbiosis between the gut microbiota and the host has been identified as an integral part of normal human physiology and physiological development. Research in germ-free or gnotobiotic animals has demonstrated the importance of this symbiosis in immune, vascular, hepatic, respiratory and metabolic systems. Disruption of the microbiota can also contribute to disease, and the microbiota has been implicated in numerous intestinal and extra-intestinal pathologies including colorectal cancer. Interactions between host and microbiota can occur either directly or indirectly, via microbial-derived metabolites. In this chapter, we focus on two major products of microbial metabolism, short-chain fatty acids and bile acids, and their role in colorectal cancer. Short-chain fatty acids are the products of microbial fermentation of complex carbohydrates and confer protection against cancer risk, while bile acids are compounds which are endogenous to the host, but undergo microbial modification in the large intestine leading to alterations in their bioactivity. Lastly, we discuss the ability of microbial modulation to mediate cancer risk and the potential to harness this ability as a prophylactic or therapeutic treatment in colorectal cancer.},
}
@article {pmid33263883,
year = {2020},
author = {Eleftherianos, I and Heryanto, C},
title = {Molecular Regulators of Entomopathogenic Nematode-Bacterial Symbiosis.},
journal = {Results and problems in cell differentiation},
volume = {69},
number = {},
pages = {453-468},
doi = {10.1007/978-3-030-51849-3_17},
pmid = {33263883},
issn = {0080-1844},
abstract = {Entomopathogenic nematodes are parasitic organisms with an exceptional capacity to infect rapidly and efficiently a wide range of insect species. Their distinct pathogenic properties have established entomopathogenic nematodes as supreme biocontrol agents of insects as well as excellent models to simulate and dissect the molecular and physiological bases of conserved strategies employed by parasitic nematodes that cause infectious diseases in humans. The extreme infectivity of entomopathogenic nematodes is due in part to the presence of certain species of Gram-negative bacteria that live in mutualistic symbiosis during the infective juvenile stage, which forms the central part of the nematode life cycle. Both nematodes and their mutualistic bacteria are capable of interfering and undermining several aspects of the insect host innate immune system during the infection process. The mutualistic bacteria are also able to modulate other biological functions in their nematode host including growth, development, and reproduction. In this review, we will focus our attention on the mutualistic relationship between entomopathogenic nematodes and their associated bacteria to discuss the nature and distinct characteristics of the regulatory mechanisms, and their molecular as well as physiological components that control this specific biological partnership.},
}
@article {pmid33263881,
year = {2020},
author = {Valdés-López, O and Reyero-Saavedra, MDR and Isidra-Arellano, MC and Sánchez-Correa, MDS},
title = {Early Molecular Dialogue Between Legumes and Rhizobia: Why Are They So Important?.},
journal = {Results and problems in cell differentiation},
volume = {69},
number = {},
pages = {409-419},
doi = {10.1007/978-3-030-51849-3_15},
pmid = {33263881},
issn = {0080-1844},
abstract = {Legume-rhizobia symbiosis has a considerable ecological relevance because it replenishes the soil with fixed-nitrogen (e.g., ammonium) for other plants. Because of this benefit to the environment, the exploitation of the legume-rhizobia symbiosis can contribute to the development of the lower input, sustainable agriculture, thereby, reducing dependency on synthetic fertilizers. To achieve this goal, it is necessary to understand the different levels of regulation of this symbiosis to enhance its nitrogen-fixation efficiency. A different line of evidence attests to the relevance of early molecular events in the establishment of a successful symbiosis between legumes and rhizobia. In this chapter, we will review the early molecular signaling in the legume-rhizobia symbiosis. We will focus on the early molecular responses that are crucial for the recognition of the rhizobia as a potential symbiont.},
}
@article {pmid33263880,
year = {2020},
author = {Shen, D and Bisseling, T},
title = {The Evolutionary Aspects of Legume Nitrogen-Fixing Nodule Symbiosis.},
journal = {Results and problems in cell differentiation},
volume = {69},
number = {},
pages = {387-408},
doi = {10.1007/978-3-030-51849-3_14},
pmid = {33263880},
issn = {0080-1844},
abstract = {Nitrogen-fixing root nodule symbiosis can sustain the development of the host plants under nitrogen-limiting conditions. Such symbiosis occurs only in a clade of angiosperms known as the nitrogen-fixing clade (NFC). It has long been proposed that root nodule symbiosis evolved several times (in parallel) in the NFC. Two recent phylogenomic studies compared the genomes of nodulating and related non-nodulating species across the four orders of the NFC and found that genes essential for nodule formation are lost or pseudogenized in the non-nodulating species. As these symbiosis genes are specifically involved in the symbiotic interaction, it means that the presence of pseudogenes and the loss of symbiosis genes strongly suggest that their ancestor, which still had functional genes, most likely had a symbiosis with nitrogen-fixing bacteria. These findings agree with the hypothesis that nodulation evolved once at the common ancestor of the NFC, and challenge the hypothesis of parallel evolution. In this chapter, we will cover the current understandings on actinorhizal-type and legume nodule development, and discuss the evolution of the legume nodule type.},
}
@article {pmid33263876,
year = {2020},
author = {Kaczanowski, S},
title = {Symbiotic Origin of Apoptosis.},
journal = {Results and problems in cell differentiation},
volume = {69},
number = {},
pages = {253-280},
doi = {10.1007/978-3-030-51849-3_10},
pmid = {33263876},
issn = {0080-1844},
abstract = {The progress of evolutionary biology has revealed that symbiosis played a basic role in the evolution of complex eukaryotic organisms, including humans. Mitochondria are actually simplified endosymbiotic bacteria currently playing the role of cellular organelles. Mitochondrial domestication occurred at the very beginning of eukaryotic evolution. Mitochondria have two different basic functions: they produce energy using oxidative respiration, and they initiate different forms of apoptotic programmed/regulated cell death. Apoptotic programmed cell death may have different cytological forms. Mechanisms of apoptotic programmed cell death exist even in the unicellular organisms, and they play a basic role in the development of complex multicellular organisms, such as fungi, green plants, and animals. Multicellularity was independently established many times among eukaryotes. There are indications that apoptotic programmed cell death is a trait required for the establishment of multicellularity. Regulated cell death is initiated by many different parallel biochemical pathways. It is generally accepted that apoptosis evolved during mitochondrial domestication. However, there are different hypothetical models of the origin of apoptosis. The phylogenetic studies of my group indicate that apoptosis probably evolved during an evolutionary arms race between host ancestral eukaryotic predators and ancestral prey mitochondria (named protomitochondria). Protomitochondrial prey produced many different toxins as a defense against predators. From these toxins evolved extant apoptotic factors. There are indications that aerobic respiration and apoptosis co-evolved and are functionally linked in extant organisms. Perturbations of apoptosis and oxidative respiration are frequently observed during neoplastic transition. Our group showed that perturbations of apoptosis in yeasts also cause perturbations of oxidative respiration.},
}
@article {pmid33263875,
year = {2020},
author = {Blackstone, NW},
title = {Chemiosmosis, Evolutionary Conflict, and Eukaryotic Symbiosis.},
journal = {Results and problems in cell differentiation},
volume = {69},
number = {},
pages = {237-251},
doi = {10.1007/978-3-030-51849-3_9},
pmid = {33263875},
issn = {0080-1844},
abstract = {Mutualistic symbiosis, in which individuals of different species cooperate and both benefit, has long been an evolutionary puzzle. Why should individuals of two different species cooperate? In this case, as in all others, cooperation is not automatic, but rather requires the mediation of evolutionary conflicts. In chemiosmosis, redox reactions produce a trans-membrane "proton-motive force" that powers energy-requiring reactions in most organisms. Chemiosmosis may also have a role in conflict mediation. Chemiosmosis rapidly produces considerable amounts of products, increasing the risk of end-product inhibition and the formation of dangerous by-products, such as reactive oxygen species. While several mechanisms can modulate chemiosmosis, potential negative effects can also be ameliorated by simply dispersing excess product into the environment. This "free lunch you are forced to make" can attract individuals of other species leading to groups, in which other organisms share the products that are released into the environment by the chemiosmotic cell or organism. Since the time of Darwin, evolutionary biology has recognized that groups are the key to the evolution of cooperation. With many small groups, chance associations of cooperators can arise, even if cooperation is selected against at the individual level. Groups of cooperators can then outcompete groups of defectors, which do not cooperate. Indeed, numerous symbioses may have arisen in this way, perhaps most notably the symbioses of host cells and chemiosmotic bacteria that gave rise to the eukaryotic cell. Other examples in which one partner relies on chemiosmotic products supplied by the other include lichens, corals or other metazoans and dinoflagellates, sap-feeding insects, and plant-rhizobia and plant-mycorrhiza interactions. More problematic are cases of gut microbiomes-for instance, those of termites, ruminants, and even human beings. Under some but not all circumstances, chemiosmosis can be co-opted into punishing defectors and enforcing cooperation, thus leading to mutualistic symbioses.},
}
@article {pmid33263871,
year = {2020},
author = {Russell, SL and Castillo, JR},
title = {Trends in Symbiont-Induced Host Cellular Differentiation.},
journal = {Results and problems in cell differentiation},
volume = {69},
number = {},
pages = {137-176},
doi = {10.1007/978-3-030-51849-3_5},
pmid = {33263871},
issn = {0080-1844},
abstract = {Bacteria participate in a wide diversity of symbiotic associations with eukaryotic hosts that require precise interactions for bacterial recognition and persistence. Most commonly, host-associated bacteria interfere with host gene expression to modulate the immune response to the infection. However, many of these bacteria also interfere with host cellular differentiation pathways to create a hospitable niche, resulting in the formation of novel cell types, tissues, and organs. In both of these situations, bacterial symbionts must interact with eukaryotic regulatory pathways. Here, we detail what is known about how bacterial symbionts, from pathogens to mutualists, control host cellular differentiation across the central dogma, from epigenetic chromatin modifications, to transcription and mRNA processing, to translation and protein modifications. We identify four main trends from this survey. First, mechanisms for controlling host gene expression appear to evolve from symbionts co-opting cross-talk between host signaling pathways. Second, symbiont regulatory capacity is constrained by the processes that drive reductive genome evolution in host-associated bacteria. Third, the regulatory mechanisms symbionts exhibit correlate with the cost/benefit nature of the association. And, fourth, symbiont mechanisms for interacting with host genetic regulatory elements are not bound by native bacterial capabilities. Using this knowledge, we explore how the ubiquitous intracellular Wolbachia symbiont of arthropods and nematodes may modulate host cellular differentiation to manipulate host reproduction. Our survey of the literature on how infection alters gene expression in Wolbachia and its hosts revealed that, despite their intermediate-sized genomes, different strains appear capable of a wide diversity of regulatory manipulations. Given this and Wolbachia's diversity of phenotypes and eukaryotic-like proteins, we expect that many symbiont-induced host differentiation mechanisms will be discovered in this system.},
}
@article {pmid33263870,
year = {2020},
author = {Schrallhammer, M and Potekhin, A},
title = {Epidemiology of Nucleus-Dwelling Holospora: Infection, Transmission, Adaptation, and Interaction with Paramecium.},
journal = {Results and problems in cell differentiation},
volume = {69},
number = {},
pages = {105-135},
doi = {10.1007/978-3-030-51849-3_4},
pmid = {33263870},
issn = {0080-1844},
abstract = {The chapter describes the exceptional symbiotic associations formed between the ciliate Paramecium and Holospora, highly infectious bacteria residing in the host nuclei. Holospora and Holospora-like bacteria (Alphaproteobacteria) are characterized by their ability for vertical and horizontal transmission in host populations, a complex biphasic life cycle, and pronounced preference for host species and colonized cell compartment. These bacteria are obligate intracellular parasites; thus, their metabolic repertoire is dramatically reduced. Nevertheless, they perform complex interactions with the host ciliate. We review ongoing efforts to unravel the molecular adaptations of these bacteria to their unusual lifestyle and the host's employment in the symbiosis. Furthermore, we summarize current knowledge on the genetic and genomic background of Paramecium-Holospora symbiosis and provide insights into the ecological and evolutionary consequences of this interaction. The diversity and occurrence of symbioses between ciliates and Holospora-like bacteria in nature is discussed in connection with transmission modes of symbionts, host specificity and compatibility of the partners. We aim to summarize 50 years of research devoted to these symbiotic systems and conclude trying to predict some perspectives for further studies.},
}
@article {pmid33263867,
year = {2020},
author = {Ryan, F},
title = {Viral Symbiosis in the Origins and Evolution of Life with a Particular Focus on the Placental Mammals.},
journal = {Results and problems in cell differentiation},
volume = {69},
number = {},
pages = {3-24},
doi = {10.1007/978-3-030-51849-3_1},
pmid = {33263867},
issn = {0080-1844},
abstract = {Advances in understanding over the last decade or so highlight the need for a reappraisal of the role of viruses in relation to the origins and evolution of cellular life, as well as in the homeostasis of the biosphere on which all of life depends. The relevant advances have, in particular, revealed an important contribution of viruses to the evolution of the placental mammals, while also contributing key roles to mammalian embryogenesis, genomic evolution, and physiology. Part of this reappraisal will include the origins of viruses, a redefinition of their quintessential nature, and a suggestion as to how we might view viruses in relation to the tree of life.},
}
@article {pmid33262856,
year = {2020},
author = {Astrop, TI and Park Boush, L and Weeks, SC},
title = {Testing Weissman's Lineage Selection Model for the Maintenance of Sex: The Evolutionary Dynamics of Clam Shrimp Reproduction over Geologic Time.},
journal = {Zoological studies},
volume = {59},
number = {},
pages = {e34},
pmid = {33262856},
issn = {1810-522X},
abstract = {One of the most perplexing questions within evolutionary biology is: "why are there so many methods of reproduction?" Contemporary theories assume that sexual reproduction should allow long term survival as dispersal and recombination of genetic material provides a population of organisms with the ability to adapt to environmental change. One of the most frustrating aspects of studying the evolution of reproductive systems is that we have not yet been able to utilize information locked within the fossil record to assess breeding system evolution in deep time. While the fossil record provides us with information on an organism's living environment, as well as some aspects of its ecology, the preservation of biological interactions (reproduction, feeding, symbiosis, communication) is exceedingly rare. Using both information from extant taxa uncovered by a plethora of biological and ecological studies and the rich representation of the Spinicaudata (Branchiopoda: Crustacea) throughout the fossil record (from the Devonian to today), we address two hypotheses of reproductive evolutionary theory: (1) that unisexual species should be short lived and less speciose than their outcrossing counterparts and (2) that androdioecy (mixtures of males and hermaphrodites) is an unstable, transitionary system that should not persist over long periods of time. We find no evidence of all-unisexual spinicaudatan taxa (clam shrimp) in the fossil record, but do find evidence of both androdioecious and dioecious clam shrimp. We find that clades with many androdioecious species are less speciose but persist longer than their mostly dioecious counterparts. These data suggest that all-unisexual lineages likely do not persist long whereas mixtures of unisexual and sexual breeding can persist for evolutionarily long periods but tend to produce fewer species than mostly sexual breeding.},
}
@article {pmid33262843,
year = {2020},
author = {Hirose, E and Nozawa, Y},
title = {Latitudinal Difference in the Species Richness of Photosymbiotic Ascidians Along the East Coast of Taiwan.},
journal = {Zoological studies},
volume = {59},
number = {},
pages = {e19},
pmid = {33262843},
issn = {1810-522X},
abstract = {Some didemnid ascidians harbor cyanobacterial symbionts, and this is the only obligate photosymbiosis system known in chordates. These photosymbiotic ascidians are found only in tropical and subtropical waters, probably because the photosymbionts are vulnerable to low temperatures. We surveyed the photosymbiotic ascidian fauna along the east coast of Taiwan. The present and previous reports recorded 13 species in Taiwan, and the species richness and composition is different in five areas along the east coast. Along the middle-east, southeast, and south coasts, five or more species have been recorded, whereas only one species has been found along the northeast coast, and no species have been recorded on the north coast. This gap in the species richness is probably related to the Kuroshio Current, which travels from south to north along the east coast of Taiwan but changes to an easterly direction off the northeast coast. Increases in water temperature due to global warming could cause northward expansion of the distribution ranges of these ascidians in the future. Hence, the photosymbiotic ascidian fauna could be an environmental indicator in subtropical, shallow water, and the present study provides a basic dataset that illustrates the current status of photosymbiotic ascidians in Taiwan.},
}
@article {pmid33261536,
year = {2020},
author = {Patil, A and Banerji, R and Kanojiya, P and Koratkar, S and Saroj, S},
title = {Bacteriophages for ESKAPE: Role in pathogenicity and measures of control.},
journal = {Expert review of anti-infective therapy},
volume = {},
number = {},
pages = {},
doi = {10.1080/14787210.2021.1858800},
pmid = {33261536},
issn = {1744-8336},
abstract = {INTRODUCTION: The quest to combat bacterial infections has dreaded humankind for centuries. Infections involving ESKAPE (Enterococcus spp., Staphylococcus aureus, Klebsiella pneumoniae, Acinetobacter baumannii, Pseudomonas aeruginosa, and Enterobacter spp.) impose therapeutic challenges due to the emergence of antimicrobial drug resistance. Recently, investigations with bacteriophages have led to the development of novel strategies against ESKAPE infections. Also, bacteriophages have been demonstrated to be instrumental in the dissemination of virulence markers in ESKAPE pathogens.
AREAS COVERED: The review highlights the potential of bacteriophage in and against the pathogenicity of antibiotic-resistant ESKAPE pathogens. The review also emphasizes the challenges of employing bacteriophage in treating ESKAPE pathogens and the knowledge gap in the bacteriophage mediated antibiotic resistance and pathogenicity in ESKAPE infections.
EXPERT OPINION: Bacteriophage infection can kill the host bacteria but in survivors can transfer genes which contribute towards survival of the pathogens in the host and resistance towards multiple antimicrobials. The knowledge on the dual role of bacteriophages in the treatment and pathogenicity will assist in the prediction and development of novel therapeutics targeting antimicrobial resistant ESKAPE. Therefore, extensive investigations on the efficacy of synthetic bacteriophage, bacteriophage cocktails and bacteriophage in combination with antibiotics are needed to develop effective therapeutics against ESKAPE infections.},
}
@article {pmid33261217,
year = {2020},
author = {Caradus, JR and Johnson, LJ},
title = {Epichloë Fungal Endophytes-From a Biological Curiosity in Wild Grasses to an Essential Component of Resilient High Performing Ryegrass and Fescue Pastures.},
journal = {Journal of fungi (Basel, Switzerland)},
volume = {6},
number = {4},
pages = {},
pmid = {33261217},
issn = {2309-608X},
abstract = {The relationship between Epichloë endophytes found in a wide range of temperate grasses spans the continuum from antagonistic to mutualistic. The diversity of asexual mutualistic types can be characterised by the types of alkaloids they produce in planta. Some of these are responsible for detrimental health and welfare issues of ruminants when consumed, while others protect the host plant from insect pests and pathogens. In many temperate regions they are an essential component of high producing resilient tall fescue and ryegrass swards. This obligate mutualism between fungus and host is a seed-borne technology that has resulted in several commercial products being used with high uptake rates by end-user farmers, particularly in New Zealand and to a lesser extent Australia and USA. However, this has not happened by chance. It has been reliant on multi-disciplinary research teams undertaking excellent science to understand the taxonomic relationships of these endophytes, their life cycle, symbiosis regulation at both the cellular and molecular level, and the impact of secondary metabolites, including an understanding of their mammalian toxicity and bioactivity against insects and pathogens. Additionally, agronomic trials and seed biology studies of these microbes have all contributed to the delivery of robust and efficacious products. The supply chain from science, through seed companies and retailers to the end-user farmer needs to be well resourced providing convincing information on the efficacy and ensuring effective quality control to result in a strong uptake of these Epichloë endophyte technologies in pastoral agriculture.},
}
@article {pmid33258195,
year = {2020},
author = {Moreno, JC and Mi, J and Alagoz, Y and Al-Babili, S},
title = {Plant Apocarotenoids: From Retrograde Signaling to Interspecific Communication.},
journal = {The Plant journal : for cell and molecular biology},
volume = {},
number = {},
pages = {},
doi = {10.1111/tpj.15102},
pmid = {33258195},
issn = {1365-313X},
abstract = {Carotenoids are isoprenoid compounds synthesized by all photosynthetic and some non-photosynthetic organisms. They are essential for photosynthesis and contribute to many other aspects of a plant's life. The oxidative breakdown of carotenoids gives rise to the formation of a diverse family of essential metabolites called apocarotenoids. This metabolic process either takes place spontaneously through reactive oxygen species (ROS) or is catalyzed by enzymes generally belonging to the carotenoid cleavage dioxygenase (CCD) family. Apocarotenoids include the phytohormones abscisic acid (ABA) and strigolactones (SLs), signaling molecules, and growth regulators. ABA and SLs are vital in regulating plant growth, development, and stress response. SLs are also an essential component in plants'rhizospheric communication with symbionts and parasites. Other apocarotenoid small molecules, such as blumenols, mycorradicins, zaxinone, anchorene, β-cyclocitral, β-cyclogeranic acid, β-ionone, and loliolide, are involved in plant growth and development, and/or contribute to different processes, including arbuscular mycorrhiza (AM) symbiosis, abiotic stress response, plant-plant and plant-herbivore interactions, and plastid retrograde signaling. There are also indications for the presence of structurally unidentifiedlinearcis-carotene-derived apocarotenoids (LCDAs), which are presumed to modulateplastid biogenesis and leaf morphology, among other developmental processes. Here, we provide an overview on the biology of old, recently discovered, and supposed plant apocarotenoid signaling molecules, describing their biosynthesis, developmental and physiological functions, and role as a messenger in plants' communication.},
}
@article {pmid33257574,
year = {2020},
author = {Sánchez-García, M and Ryberg, M and Khan, FK and Varga, T and Nagy, LG and Hibbett, DS},
title = {Fruiting body form, not nutritional mode, is the major driver of diversification in mushroom-forming fungi.},
journal = {Proceedings of the National Academy of Sciences of the United States of America},
volume = {},
number = {},
pages = {},
doi = {10.1073/pnas.1922539117},
pmid = {33257574},
issn = {1091-6490},
abstract = {With ∼36,000 described species, Agaricomycetes are among the most successful groups of Fungi. Agaricomycetes display great diversity in fruiting body forms and nutritional modes. Most have pileate-stipitate fruiting bodies (with a cap and stalk), but the group also contains crust-like resupinate fungi, polypores, coral fungi, and gasteroid forms (e.g., puffballs and stinkhorns). Some Agaricomycetes enter into ectomycorrhizal symbioses with plants, while others are decayers (saprotrophs) or pathogens. We constructed a megaphylogeny of 8,400 species and used it to test the following five hypotheses regarding the evolution of morphological and ecological traits in Agaricomycetes and their impact on diversification: 1) resupinate forms are plesiomorphic, 2) pileate-stipitate forms promote diversification, 3) the evolution of gasteroid forms is irreversible, 4) the ectomycorrhizal (ECM) symbiosis promotes diversification, and 5) the evolution of ECM symbiosis is irreversible. The ancestor of Agaricomycetes was a saprotroph with a resupinate fruiting body. There have been 462 transitions in the examined morphologies, including 123 origins of gasteroid forms. Reversals of gasteroid forms are highly unlikely but cannot be rejected. Pileate-stipitate forms are correlated with elevated diversification rates, suggesting that this morphological trait is a key to the success of Agaricomycetes. ECM symbioses have evolved 36 times in Agaricomycetes, with several transformations to parasitism. Across the entire 8,400-species phylogeny, diversification rates of ectomycorrhizal lineages are no greater than those of saprotrophic lineages. However, some ECM lineages have elevated diversification rates compared to their non-ECM sister clades, suggesting that the evolution of symbioses may act as a key innovation at local phylogenetic scales.},
}
@article {pmid33257562,
year = {2020},
author = {Martinson, VG and Gawryluk, RMR and Gowen, BE and Curtis, CI and Jaenike, J and Perlman, SJ},
title = {Multiple origins of obligate nematode and insect symbionts by a clade of bacteria closely related to plant pathogens.},
journal = {Proceedings of the National Academy of Sciences of the United States of America},
volume = {117},
number = {50},
pages = {31979-31986},
pmid = {33257562},
issn = {1091-6490},
abstract = {Obligate symbioses involving intracellular bacteria have transformed eukaryotic life, from providing aerobic respiration and photosynthesis to enabling colonization of previously inaccessible niches, such as feeding on xylem and phloem, and surviving in deep-sea hydrothermal vents. A major challenge in the study of obligate symbioses is to understand how they arise. Because the best studied obligate symbioses are ancient, it is especially challenging to identify early or intermediate stages. Here we report the discovery of a nascent obligate symbiosis in Howardula aoronymphium, a well-studied nematode parasite of Drosophila flies. We have found that Haoronymphium and its sister species harbor a maternally inherited intracellular bacterial symbiont. We never find the symbiont in nematode-free flies, and virtually all nematodes in the field and the laboratory are infected. Treating nematodes with antibiotics causes a severe reduction in fly infection success. The association is recent, as more distantly related insect-parasitic tylenchid nematodes do not host these endosymbionts. We also report that the Howardula nematode symbiont is a member of a widespread monophyletic group of invertebrate host-associated microbes that has independently given rise to at least four obligate symbioses, one in nematodes and three in insects, and that is sister to Pectobacterium, a lineage of plant pathogenic bacteria. Comparative genomic analysis of this group, which we name Candidatus Symbiopectobacterium, shows signatures of genome erosion characteristic of early stages of symbiosis, with the Howardula symbiont's genome containing over a thousand predicted pseudogenes, comprising a third of its genome.},
}
@article {pmid33255636,
year = {2020},
author = {Kumar, H and Collado, MC and Wopereis, H and Salminen, S and Knol, J and Roeselers, G},
title = {The Bifidogenic Effect Revisited-Ecology and Health Perspectives of Bifidobacterial Colonization in Early Life.},
journal = {Microorganisms},
volume = {8},
number = {12},
pages = {},
pmid = {33255636},
issn = {2076-2607},
abstract = {Extensive microbial colonization of the infant gastrointestinal tract starts after parturition. There are several parallel mechanisms by which early life microbiome acquisition may proceed, including early exposure to maternal vaginal and fecal microbiota, transmission of skin associated microbes, and ingestion of microorganisms present in breast milk. The crucial role of vertical transmission from the maternal microbial reservoir during vaginal delivery is supported by the shared microbial strains observed among mothers and their babies and the distinctly different gut microbiome composition of caesarean-section born infants. The healthy infant colon is often dominated by members of the keystone genus Bifidobacterium that have evolved complex genetic pathways to metabolize different glycans present in human milk. In exchange for these host-derived nutrients, bifidobacteria's saccharolytic activity results in an anaerobic and acidic gut environment that is protective against enteropathogenic infection. Interference with early-life microbiota acquisition and development could result in adverse health outcomes. Compromised microbiota development, often characterized by decreased abundance of Bifidobacterium species has been reported in infants delivered prematurely, delivered by caesarean section, early life antibiotic exposure and in the case of early life allergies. Various microbiome modulation strategies such as probiotic, prebiotics, synbiotics and postbiotics have been developed that are able to generate a bifidogenic shift and help to restore the microbiota development. This review explores the evolutionary ecology of early-life type Bifidobacterium strains and their symbiotic relationship with humans and discusses examples of compromised microbiota development in which stimulating the abundance and activity of Bifidobacterium has demonstrated beneficial associations with health.},
}
@article {pmid33254825,
year = {2021},
author = {Riaz, M and Kamran, M and Fang, Y and Wang, Q and Cao, H and Yang, G and Deng, L and Wang, Y and Zhou, Y and Anastopoulos, I and Wang, X},
title = {Arbuscular mycorrhizal fungi-induced mitigation of heavy metal phytotoxicity in metal contaminated soils: A critical review.},
journal = {Journal of hazardous materials},
volume = {402},
number = {},
pages = {123919},
doi = {10.1016/j.jhazmat.2020.123919},
pmid = {33254825},
issn = {1873-3336},
abstract = {The heavy metal pollution is a worldwide problem and has received a serious concern for the ecosystem and human health. In the last decade, remediation of the agricultural polluted soil has attracted great attention. Phytoremediation is one of the technologies that effectively alleviate heavy metal toxicity, however, this technique is limited to many factors contributing to low plant growth rate and nature of metal toxicities. Arbuscular mycorrhizal fungi (AMF) assisted alleviation of heavy metal phytotoxicity is a cost-effective and environment-friendly strategy. AMF have a symbiotic relationship with the host plant. The bidirectional exchange of resources is a hallmark and also a functional necessity in mycorrhizal symbiosis. During the last few years, a significant progress in both physiological and molecular mechanisms regarding roles of AMF in the alleviation of heavy metals (HMs) toxicities in plants, acquisition of nutrients, and improving plant performance under toxic conditions of HMs has been well studied. This review summarized the current knowledge regarding AMF assisted remediation of heavy metals and some of the strategies used by mycorrhizal fungi to cope with stressful environments. Moreover, this review provides the information of both molecular and physiological responses of mycorrhizal plants as well as AMF to heavy metal stress which could be helpful for exploring new insight into the mechanisms of HMs remediation by utilizing AMF.},
}
@article {pmid33254523,
year = {2020},
author = {Benny, S and Mishra, R and Manojkumar, MK and Aneesh, TP},
title = {From Warburg effect to Reverse Warburg effect; the new horizons of anti-cancer therapy.},
journal = {Medical hypotheses},
volume = {144},
number = {},
pages = {110216},
doi = {10.1016/j.mehy.2020.110216},
pmid = {33254523},
issn = {1532-2777},
abstract = {An old ideology of killing the cancer cells by starving them is the underlying concept of the Warburg effect. It is the process of aerobic glycolysis exhibited by the cancer cells irrespective of anaerobic glycolysis or mitochondrial oxidative phosphorylation following by their healthy counterparts. Dr Otto Heinrich Warburg proposed this abnormal metabolic behaviour of tumour cells in 1920. This phenomenon illustrates the metabolic switching in tumour cells from oxidative phosphorylation to aerobic glycolysis triggered by an injury to the mitochondrial respiration. A modernised perspective of the Warburg hypothesis termed the Reverse Warburg effect introduced in 2009, with a two-compartment model describing the metabolic symbiosis between cancer cells and its neighbouring stromal cells or cancer-associated fibroblasts. This theory is elucidating the aerobic glycolysis occurring in cancer-associated fibroblasts which leads to the generation and deposition of the lactate in tumour microenvironment along with its significance. The transportation of lactate to and from the cancer cell and extracellular space is facilitated by the lactate transporters called monocarboxylate transporters. This lactate generated irrespective of the hypoxic or aerobic conditions acts as a primary metabolic fuel for the cancer cells. Besides, it will create a tumour microenvironment that is favouring the progression and metastasis of malignancy through several means. Overall, the lactate produced through this metabolic reprogramming is supporting and worsening the conditions of cancer. The concept of the Reverse Warburg effect proposes a new anti-cancer treatment modality by preventing the generation and transport of lactate through the inhibition of monocarboxylate transporters and in turn, defeating the cancer disease by arresting the cancer cells along with silencing tumour microenvironment.},
}
@article {pmid33254468,
year = {2021},
author = {Okurowska, K and Karunakaran, E and Al-Farttoosy, A and Couto, N and Pandhal, J},
title = {Adapting the algal microbiome for growth on domestic landfill leachate.},
journal = {Bioresource technology},
volume = {319},
number = {},
pages = {124246},
doi = {10.1016/j.biortech.2020.124246},
pmid = {33254468},
issn = {1873-2976},
mesh = {Biodegradation, Environmental ; *Chlorella vulgaris ; *Microbiota ; RNA, Ribosomal, 16S/genetics ; *Water Pollutants, Chemical/analysis ; },
abstract = {We aimed to improve algal growth rate on leachate by optimising the algal microbiome. An algal-bacterial consortium was enriched from landfill leachate and subjected to 24 months of adaptive laboratory evolution, increasing the growth rate of the dominant algal strain, Chlorella vulgaris, almost three-fold to 0.2 d-1. A dramatic reduction in nitrate production suggested a shift in biological utilisation of ammoniacal-N, supported by molecular 16S rRNA taxonomic analyses, where Nitrosomonas numbers were not detected in the adapted consortium. A PICRUSt approach predicted metagenomic functional content and revealed a high number of sequences belonging to bioremediation pathways, including degradation of aromatic compounds, benzoate and naphthalene, as well as pathways known to be involved in algal-bacterial symbiosis. This study enhances our understanding of beneficial mechanisms in algal-bacterial associations in complex effluents, and ultimately enables the bottom-up design of optimised algal microbiomes for exploitation within industry.},
}
@article {pmid33253747,
year = {2020},
author = {Budgude, P and Kale, V and Vaidya, A},
title = {Cryopreservation of mesenchymal stromal cell-derived extracellular vesicles using trehalose maintains their ability to expand hematopoietic stem cells in vitro.},
journal = {Cryobiology},
volume = {},
number = {},
pages = {},
doi = {10.1016/j.cryobiol.2020.11.009},
pmid = {33253747},
issn = {1090-2392},
abstract = {The multitude of clinical trials using mesenchymal stromal cells (MSCs) has underscored their significance as a promising cell source for regenerative therapies. Most studies have however shown that MSCs get entrapped into the microvasculature of lungs, liver and spleen. In addition to intercellular communication, MSCs exert their effects in a paracrine manner by secretion of extracellular vesicles (EVs). The therapeutic effects of MSC-derived EVs have been examined in several diseases such as hepatic failure, liver injury, hematopoiesis etc. Therefore, optimization of cryopreservation strategies for the long-term storage of functional EVs could help in the development of off-the-shelf biologics. The aim of this study was to develop an optimal cryopreservation strategy for the efficient storage of both types of EVs - Microvesicles (MVs) and exosomes, independently, and to further examine the effect of the cryopreserved EVs on the ex vivo expansion of HSCs. MVs and exosomes were separately cryopreserved at different temperatures using PBS or PBS supplemented with trehalose (pTRE), and these cryopreserved EVs were then assessed for their functionality after revival. We found that addition of trehalose during cryopreservation helped in maintaining the morphology and functionality of the EVs, as assessed by their HSC-supportive potential, ability to expand phenotypically defined HSCs and ability to maintain the chemotactic migration potential of the HSCs co-cultured with them. This strategy could prove to be beneficial for facilitating the use of EVs as cell-free ready-to-use biologics for the ex vivo expansion of HSCs and in regenerative medicine.},
}
@article {pmid33252650,
year = {2020},
author = {Nasir, F and Bahadur, A and Lin, X and Gao, Y and Tian, C},
title = {Novel Insights into Host Receptors and Receptor-mediated Signaling that Regulate Arbuscular Mycorrhizal Symbiosis.},
journal = {Journal of experimental botany},
volume = {},
number = {},
pages = {},
doi = {10.1093/jxb/eraa538},
pmid = {33252650},
issn = {1460-2431},
abstract = {More than 80% of land plant species benefit from symbiotic partnerships with arbuscular mycorrhizal (AM) fungi that assist in nutrient acquisition and enhance the ability of host plants to adapt to environmental constraints. Host-generated plasma membrane-residing receptor-like kinases and the α/β-hydrolases, e.g. DWARF14-LIKE (D14L), a putative karrikin receptor, are used to detect the presence of AM fungi prior to physical contact between the host and fungus. Detection induces the activation of symbiosis-related transcriptional programming, enabling the successful establishment of AM symbiosis. In order to prevent hyper-colonization and to maintain a mutually beneficial association, the host plants precisely monitor and control AM symbiosis during the post-symbiotic stage via different molecular strategies. While previous studies have elucidated how host plant receptors and receptor-mediated signaling regulate AM symbiosis, the molecular details underlying these processes remain poorly understood. The recent identification of a rice (Oryza sativa) CHITIN-ELICITOR RECEPTOR-KINASE 1 (OsCERK1) interaction partner MYC FACTOR RECEPTOR 1 (OsMYR1), as well as new insights into D14L-receptor- and SUPER NUMERIC NODULES 1 (SUNN1) receptor-mediated signaling have improved our understanding of how host plant receptors and their corresponding signaling regulate AM symbiosis. The present review summarizes these and other current findings that have increased our limited understanding of receptor-mediated signaling mechanisms involved in the regulation of AM symbiosis. The identified receptors and/or their downstream signaling components could potentially be used to engineer economically-important crops with improved agronomic traits by conferring the ability to control the colonization of AM fungi in a precise manner.},
}
@article {pmid33250866,
year = {2020},
author = {Taboada-Castro, H and Castro-Mondragón, JA and Aguilar-Vera, A and Hernández-Álvarez, AJ and van Helden, J and Encarnación-Guevara, S},
title = {RhizoBindingSites, a Database of DNA-Binding Motifs in Nitrogen-Fixing Bacteria Inferred Using a Footprint Discovery Approach.},
journal = {Frontiers in microbiology},
volume = {11},
number = {},
pages = {567471},
pmid = {33250866},
issn = {1664-302X},
abstract = {Basic knowledge of transcriptional regulation is needed to understand the mechanisms governing biological processes, i.e., nitrogen fixation by Rhizobiales bacteria in symbiosis with leguminous plants. The RhizoBindingSites database is a computer-assisted framework providing motif-gene-associated conserved sequences potentially implicated in transcriptional regulation in nine symbiotic species. A dyad analysis algorithm was used to deduce motifs in the upstream regulatory region of orthologous genes, and only motifs also located in the gene seed promoter with a p-value of 1e-4 were accepted. A genomic scan analysis of the upstoream sequences with these motifs was performed. These predicted binding sites were categorized according to low, medium and high homology between the matrix and the upstream regulatory sequence. On average, 62.7% of the genes had a motif, accounting for 80.44% of the genes per genome, with 19613 matrices (a matrix is a representation of a motif). The RhizoBindingSites database provides motif and gene information, motif conservation in the order Rhizobiales, matrices, motif logos, regulatory networks constructed from theoretical or experimental data, a criterion for selecting motifs and a guide for users. The RhizoBindingSites database is freely available online at rhizobindingsites.ccg.unam.mx.},
}
@article {pmid33249664,
year = {2020},
author = {Porro, B and Zamoum, T and Mallien, C and Hume, BCC and Voolstra, CR and Röttinger, E and Furla, P and Forcioli, D},
title = {Horizontal acquisition of Symbiodiniaceae in the Anemonia viridis (Cnidaria, Anthozoa) species complex.},
journal = {Molecular ecology},
volume = {},
number = {},
pages = {},
doi = {10.1111/mec.15755},
pmid = {33249664},
issn = {1365-294X},
support = {ANR-12-ADAP-0016//Agence Nationale de la Recherche/ ; },
abstract = {All metazoans are in fact holobionts, resulting from the association of several organisms, and organismal adaptation is then due to the composite response of this association to the environment. Deciphering the mechanisms of symbiont acquisition in a holobiont is therefore essential to understanding the extent of its adaptive capacities. In cnidarians, some species acquire their photosynthetic symbionts directly from their parents (vertical transmission) but may also acquire symbionts from the environment (horizontal acquisition) at the adult stage. The Mediterranean snakelocks sea anemone, Anemonia viridis (Forskål, 1775), passes down symbionts from one generation to the next by vertical transmission, but the capacity for such horizontal acquisition is still unexplored. To unravel the flexibility of the association between the different host lineages identified in A. viridis and its Symbiodiniaceae, we genotyped both the animal hosts and their symbiont communities in members of host clones in five different locations in the North Western Mediterranean Sea. The composition of within-host-symbiont populations was more dependent on the geographical origin of the hosts than their membership to a given lineage or even to a given clone. Additionally, similarities in host-symbiont communities were greater among genets (i.e. among different clones) than among ramets (i.e. among members of the same given clonal genotype). Taken together, our results demonstrate that A. viridis may form associations with a range of symbiotic dinoflagellates and suggest a capacity for horizontal acquisition. A mixed-mode transmission strategy in A. viridis, as we posit here, may help explain the large phenotypic plasticity that characterizes this anemone.},
}
@article {pmid33248899,
year = {2021},
author = {Santander, C and Aroca, R and Cartes, P and Vidal, G and Cornejo, P},
title = {Aquaporins and cation transporters are differentially regulated by two arbuscular mycorrhizal fungi strains in lettuce cultivars growing under salinity conditions.},
journal = {Plant physiology and biochemistry : PPB},
volume = {158},
number = {},
pages = {396-409},
doi = {10.1016/j.plaphy.2020.11.025},
pmid = {33248899},
issn = {1873-2690},
abstract = {The aim was to identify the effects of AM symbiosis on the expression patterns of genes associated with K+ and Na+ compartmentalization and translocation and on K+/Na+ homeostasis in some lettuce (Lactuca sativa) cultivars as well as the effects of the relative abundance of plant AQPs on plant water status. Two AM fungi species (Funneliformis mosseae and Claroideoglomus lamellosum) isolated from the hyper-arid Atacama Desert (northern Chile) were inoculated to two lettuce cultivars (Grand Rapids and Lollo Bionda), and watered with 0 and 60 mM NaCl. At 60 days of plant growth, the AM symbiotic development, biomass production, nutrient content (Pi, Na+, K+), physiological parameters, gene expressions of ion channels and transporters (NHX and HKT1), and aquaporins proteins abundance (phosphorylated and non-phosphorylated) were evaluated. Salinity increased the AM root colonization by both inocula. AM lettuce plants showed an improved growth, increased relative water content and improved of K/Na ratio in root. In Grand Rapids cultivar, the high efficiency of photosystem II was higher than Lollo Bionda cultivar; on the contrary, stomatal conductance was higher in Lollo Bionda. Nevertheless, both parameters were increased by AM colonization. In the same way, LsaHKT1;1, LsaHKT1;6, LsaNHX2, LsaNHX4, LsaNHX6 and LsaNHX8 genes and aquaporins PIP2 were up-regulated differentially by both AM fungi. The improved plant growth was closely related to a higher water status due to increased PIP2 abundance, as well as to the upregulation of LsaNHX gene expression, which concomitantly improved plant nutrition and K+/Na+ homeostasis maintenance.},
}
@article {pmid33246955,
year = {2020},
author = {Cooke, I and Ying, H and Forêt, S and Bongaerts, P and Strugnell, JM and Simakov, O and Zhang, J and Field, MA and Rodriguez-Lanetty, M and Bell, SC and Bourne, DG and van Oppen, MJ and Ragan, MA and Miller, DJ},
title = {Genomic signatures in the coral holobiont reveal host adaptations driven by Holocene climate change and reef specific symbionts.},
journal = {Science advances},
volume = {6},
number = {48},
pages = {},
pmid = {33246955},
issn = {2375-2548},
abstract = {Genetic signatures caused by demographic and adaptive processes during past climatic shifts can inform predictions of species' responses to anthropogenic climate change. To identify these signatures in Acropora tenuis, a reef-building coral threatened by global warming, we first assembled the genome from long reads and then used shallow whole-genome resequencing of 150 colonies from the central inshore Great Barrier Reef to inform population genomic analyses. We identify population structure in the host that reflects a Pleistocene split, whereas photosymbiont differences between reefs most likely reflect contemporary (Holocene) conditions. Signatures of selection in the host were associated with genes linked to diverse processes including osmotic regulation, skeletal development, and the establishment and maintenance of symbiosis. Our results suggest that adaptation to post-glacial climate change in A. tenuis has involved selection on many genes, while differences in symbiont specificity between reefs appear to be unrelated to host population structure.},
}
@article {pmid33244313,
year = {2020},
author = {Pan, H and Pierson, LS and Pierson, EA},
title = {PcsR2 Is a LuxR-Type Regulator That Is Upregulated on Wheat Roots and Is Unique to Pseudomonas chlororaphis.},
journal = {Frontiers in microbiology},
volume = {11},
number = {},
pages = {560124},
pmid = {33244313},
issn = {1664-302X},
abstract = {LuxR solos are common in plant-associated bacteria and increasingly recognized for playing important roles in plant-microbe interkingdom signaling. Unlike the LuxR-type transcriptional regulators of prototype LuxR/LuxI quorum sensing systems, luxR solos do not have a LuxI-type autoinducer synthase gene associated with them. LuxR solos in plant-pathogenic bacteria are important for virulence and in plant endosymbionts contribute to symbiosis. In the present study, we characterized an atypical LuxR solo, PcsR2, in the biological control species Pseudomonas chlororaphis 30-84 that is highly conserved among sequenced P. chlororaphis strains. Unlike most LuxR solos in the plant-associated bacteria characterized to date, pcsR2 is not associated with a proline iminopeptidase gene and the protein has an atypical N-terminal binding domain. We created a pcsR2 deletion mutant and used quantitative RT-PCR to show that the expression of pcsR2 and genes in the operon immediately downstream was upregulated ∼10-fold when the wild type strain was grown on wheat roots compared to planktonic culture. PcsR2 was involved in upregulation. Using a GFP transcriptional reporter, we found that expression of pcsR2 responded specifically to root-derived substrates as compared to leaf-derived substrates but not to endogenous AHLs. Compared to the wild type, the mutant was impaired in the ability to utilize root carbon and nitrogen sources in wheat root macerate and to colonize wheat roots. Phenazine production and most biofilm traits previously shown to be correlated with phenazine production also were diminished in the mutant. Gene expression of several of the proteins in the phenazine regulatory network including PhzR, Pip (phenazine inducing protein) and RpeA/RpeB were reduced in the mutant, and overexpression of these genes in trans restored phenazine production in the mutant to wild-type levels, indicating PcsR2 affects the activity of the these regulatory genes upstream of RpeA/RpeB via an undetermined mechanism. Our results indicate PcsR2 upregulates the expression of the adjacent operon in response to unknown wheat root-derived signals and belongs to a novel subfamily of LuxR-type transcriptional regulators found in sequenced P. chlororaphis strains.},
}
@article {pmid33243641,
year = {2020},
author = {Hu, B and Hu, S and Chen, Z and Vymazal, J},
title = {Employ of arbuscular mycorrhizal fungi for pharmaceuticals ibuprofen and diclofenac removal in mesocosm-scale constructed wetlands.},
journal = {Journal of hazardous materials},
volume = {},
number = {},
pages = {124524},
doi = {10.1016/j.jhazmat.2020.124524},
pmid = {33243641},
issn = {1873-3336},
abstract = {This study investigated the effects of arbuscular mycorrhizal fungi (AMF) colonization on the growth of wetland plants (Glyceria maxima), and treatment performance in constructed wetlands (CWs) under the stress of pharmaceuticals ibuprofen (IBU) and diclofenac (DCF). Results showed that the growth of G. maxima was significantly increased by AMF colonization. AMF significantly increased the activities of antioxidant enzymes (peroxidase and superoxide dismutase) and soluble protein content in wetland plants, but the contents of malondialdehyde and O2•- were reduced. The removal efficiencies of TOC, PO43--P, NH4+-N, and TN were increased in AMF+ treatments by 6%, 11%, 15% and 11%, respectively. AMF increased the removal efficiencies of IBU and DCF by 6-14% and 2-21%, respectively, and reduced the content of their metabolites (2-OH IBU, CA IBU and 4'-OH DCF) in the effluent. Besides, the presence of AMF increased the contents of IBU and DCF in plant roots, while decreased their transportation to shoots. AMF symbiosis decreased the contents of IBU metabolites (2-OH IBU and CA IBU) but increased the contents of DCF metabolite (4'-OH DCF) in the roots of the host plant. In conclusion, these results indicated that AMF plays a promising role in CWs for emerging pollutants removal.},
}
@article {pmid33242081,
year = {2020},
author = {Maity, S and Ambatipudi, K},
title = {Mammary microbial dysbiosis leads to the zoonosis of bovine mastitis: a One-Health perspective.},
journal = {FEMS microbiology ecology},
volume = {97},
number = {1},
pages = {},
doi = {10.1093/femsec/fiaa241},
pmid = {33242081},
issn = {1574-6941},
abstract = {Bovine mastitis is a prototypic emerging and reemerging bacterial disease that results in cut-by-cut torture to animals, public health and the global economy. Pathogenic microbes causing mastitis have overcome a series of hierarchical barriers resulting in the zoonotic transmission from bovines to humans either by proximity or remotely through milk and meat. The disease control is challenging and has been attributed to faulty surveillance systems to monitor their emergence at the human-animal interface. The complex interaction between the pathogens, the hidden pathobionts and commensals of the bovine mammary gland that create a menace during mastitis remains unexplored. Here, we review the zoonotic potential of these pathogens with a primary focus on understanding the interplay between the host immunity, mammary ecology and the shift from symbiosis to dysbiosis. We also address the pros and cons of the current management strategies and the extent of the success in implementing the One-Health approach to keep these pathogens at bay.},
}
@article {pmid33240603,
year = {2020},
author = {Aichelman, HE and Barshis, DJ},
title = {Adaptive divergence, neutral panmixia, and algal symbiont population structure in the temperate coral Astrangia poculata along the Mid-Atlantic United States.},
journal = {PeerJ},
volume = {8},
number = {},
pages = {e10201},
pmid = {33240603},
issn = {2167-8359},
abstract = {Astrangia poculata is a temperate scleractinian coral that exists in facultative symbiosis with the dinoflagellate alga Breviolum psygmophilum across a range spanning the Gulf of Mexico to Cape Cod, Massachusetts. Our previous work on metabolic thermal performance of Virginia (VA) and Rhode Island (RI) populations of A. poculata revealed physiological signatures of cold (RI) and warm (VA) adaptation of these populations to their respective local thermal environments. Here, we used whole-transcriptome sequencing (mRNA-Seq) to evaluate genetic differences and identify potential loci involved in the adaptive signature of VA and RI populations. Sequencing data from 40 A. poculata individuals, including 10 colonies from each population and symbiotic state (VA-white, VA-brown, RI-white, and RI-brown), yielded a total of 1,808 host-associated and 59 algal symbiont-associated single nucleotide polymorphisms (SNPs) post filtration. Fst outlier analysis identified 66 putative high outlier SNPs in the coral host and 4 in the algal symbiont. Differentiation of VA and RI populations in the coral host was driven by putatively adaptive loci, not neutral divergence (Fst = 0.16, p = 0.001 and Fst = 0.002, p = 0.269 for outlier and neutral SNPs respectively). In contrast, we found evidence of neutral population differentiation in B. psygmophilum (Fst = 0.093, p = 0.001). Several putatively adaptive host loci occur on genes previously associated with the coral stress response. In the symbiont, three of four putatively adaptive loci are associated with photosystem proteins. The opposing pattern of neutral differentiation in B. psygmophilum, but not the A. poculata host, reflects the contrasting dynamics of coral host and algal symbiont population connectivity, dispersal, and gene by environment interactions.},
}
@article {pmid33236822,
year = {2020},
author = {Mortezaee, K},
title = {Redox tolerance and metabolic reprogramming in solid tumors.},
journal = {Cell biology international},
volume = {},
number = {},
pages = {},
doi = {10.1002/cbin.11506},
pmid = {33236822},
issn = {1095-8355},
abstract = {Tumor cells are needed to cope with the host environment in order to maintain their survival and keep growing in hard conditions. This infers that tumors must acquire characteristics more potent than what seen for normal tissue cells, without which they are condemned to disruption. As for example, cancer cells have more potent redox tolerance compared to normal cells, which is due to their high adaptation to the oxidative crisis. In addition, increased demand for bioenergetics and biosynthesis can cause a rise of nutrient uptake in tumors. Utilizing nutrients in low nutrient conditions infers that tumors are also equipped with adaptive metabolic processes. Switching the metabolic demands toward glucose consumption upon exposure to the hypoxic TME, or changing toward using other sources when there is an over-consumption of glucose in the tumor area are examples of fitness metabolic systems in tumors. In fact, cancer cells in cooperation with their nearby stroma (in a process called metabolic coupling) can reprogram their metabolic systems in their favor. This infers the high importance of stroma for meeting the metabolic demands of a growing tumor, an example in this context is the metabolic symbiosis between cancer associated fibroblasts (CAFs) with cancer cells. The point is that redox tolerance and metabolic reprogramming are inter-related, and that, without a doubt, disruption of redox tolerance systems by transient exposure to either oxidative or antioxidative loading, or targeting metabolic rewiring by modulation of tumor glucose availability, controlling tumor/stroma interactions, etc. can be effective from therapeutic window. This article is protected by copyright. All rights reserved.},
}
@article {pmid33236502,
year = {2020},
author = {Ahmad, F and Yang, GY and Liang, SY and Zhou, QH and Gaal, HA and Mo, JC},
title = {Multipartite symbioses in fungus-growing termites (Blattodea: Termitidae, Macrotermitinae) for the degradation of lignocellulose.},
journal = {Insect science},
volume = {},
number = {},
pages = {},
doi = {10.1111/1744-7917.12890},
pmid = {33236502},
issn = {1744-7917},
support = {31770686//National Natural Science Foundation of China/ ; },
abstract = {Fungus-growing termites are among the most successful herbivorous animals and improve crop productivity and soil fertility. A range of symbiotic organisms can be found inside their nests. However, interactions of termites with these symbionts are poorly understood. This review provides detailed information on the role of multipartite symbioses (between termitophiles, termites, fungi, and bacteria) in fungus-growing termites for lignocellulose degradation. The specific functions of each component in the symbiotic system are also discussed. Based on previous studies, we argue that the enzymatic contribution from the host, fungus, and bacteria greatly facilitates the decomposition of complex polysaccharide plant materials. The host-termitophile interaction protects the termite nest from natural enemies and maintains the stability of the microenvironment inside the colony.},
}
@article {pmid33235281,
year = {2020},
author = {Gorman, LM and Wilkinson, SP and Kitchen, SA and Oakley, CA and Grossman, AR and Weis, VM and Davy, SK},
title = {Phylogenetic analysis of cell-cycle regulatory proteins within the Symbiodiniaceae.},
journal = {Scientific reports},
volume = {10},
number = {1},
pages = {20473},
pmid = {33235281},
issn = {2045-2322},
abstract = {In oligotrophic waters, cnidarian hosts rely on symbiosis with their photosynthetic dinoflagellate partners (family Symbiodiniaceae) to obtain the nutrients they need to grow, reproduce and survive. For this symbiosis to persist, the host must regulate the growth and proliferation of its symbionts. One of the proposed regulatory mechanisms is arrest of the symbiont cell cycle in the G1 phase, though the cellular mechanisms involved remain unknown. Cell-cycle progression in eukaryotes is controlled by the conserved family of cyclin-dependent kinases (CDKs) and their partner cyclins. We identified CDKs and cyclins in different Symbiodiniaceae species and examined their relationship to homologs in other eukaryotes. Cyclin proteins related to eumetazoan cell-cycle-related cyclins A, B, D, G/I and Y, and transcriptional cyclin L, were identified in the Symbiodiniaceae, alongside several alveolate-specific cyclin A/B proteins, and proteins related to protist P/U-type cyclins and apicomplexan cyclins. The largest expansion of Symbiodiniaceae cyclins was in the P/U-type cyclin groups. Proteins related to eumetazoan cell-cycle-related CDKs (CDK1) were identified as well as transcription-related CDKs. The largest expansion of CDK groups was, however, in alveolate-specific groups which comprised 11 distinct CDK groups (CDKA-J) with CDKB being the most widely distributed CDK protein. As a result of its phylogenetic position, conservation across Symbiodiniaceae species, and the presence of the canonical CDK motif, CDKB emerged as a likely candidate for a Saccharomyces cerevisiae Cdc28/Pho85-like homolog in Symbiodiniaceae. Similar to cyclins, two CDK-groups found in Symbiodiniaceae species were solely associated with apicomplexan taxa. A comparison of Breviolum minutum CDK and cyclin gene expression between free-living and symbiotic states showed that several alveolate-specific CDKs and two P/U-type cyclins exhibited altered expression in hospite, suggesting that symbiosis influences the cell cycle of symbionts on a molecular level. These results highlight the divergence of Symbiodiniaceae cell-cycle proteins across species. These results have important implications for host control of the symbiont cell cycle in novel cnidarian-dinoflagellate symbioses.},
}
@article {pmid33232849,
year = {2020},
author = {Youseif, SH and Abd El-Megeed, FH and Mohamed, AH and Ageez, A and Veliz, E and Martínez-Romero, E},
title = {Diverse Rhizobium strains isolated from root nodules of Trifolium alexandrinum in Egypt and symbiovars.},
journal = {Systematic and applied microbiology},
volume = {44},
number = {1},
pages = {126156},
doi = {10.1016/j.syapm.2020.126156},
pmid = {33232849},
issn = {1618-0984},
abstract = {Berseem clover (T. alexandrinum) is the main forage legume crop used as animal feed in Egypt. Here, eighty rhizobial isolates were isolated from root nodules of berseem clover grown in different regions in Egypt and were grouped by RFLP-16S rRNA ribotyping. Representative isolates were characterized using phylogenetic analyses of the 16S rRNA, rpoB, glnA, pgi, and nodC genes. We also investigated the performance of these isolates using phenotypic tests and nitrogen fixation efficiency assays. The majority of strains (<90%) were closely related to Rhizobium aegyptiacum and Rhizobium aethiopicum and of the remaining strains, six belonged to the Rhizobium leguminosarum genospecies complex and only one strain was assigned to Agrobacterium fabacearum. Despite their heterogeneous chromosomal background, most of the strains shared nodC gene alleles corresponding to symbiovar trifolii. Some of the strains closely affiliated to R. aegyptiacum and R. aethiopicum had superior nodulation and nitrogen fixation capabilities in berseem clover, compared to the commercial inoculant (Okadein®) and N-added treatments. R. leguminosarum strain NGB-CR 17 that harbored a nodC allele typical of symbiovar viciae, was also able to form an effective symbiosis with clover. Two strains with nodC alleles of symbiovar trifolii, R. aegyptiacum strains NGB-CR 129 and 136, were capable of forming effective nodules in Phaseolus vulgaris in axenic greenhouse conditions. This adds the symbiovar trifolii which is well-established in the Egyptian soils to the list of symbiovars that form nodules in P. vulgaris.},
}
@article {pmid33231729,
year = {2020},
author = {Li, Q and Kuo, YW and Lin, KH and Huang, W and Deng, C and Yeh, KW and Chen, SP},
title = {Piriformospora indica colonization increases the growth, development, and herbivory resistance of sweet potato (Ipomoea batatas L.).},
journal = {Plant cell reports},
volume = {},
number = {},
pages = {},
doi = {10.1007/s00299-020-02636-7},
pmid = {33231729},
issn = {1432-203X},
support = {2018N0069//Fujian Provincial Department of Science and Technology/ ; 2020N0201//Fujian Provincial Department of Science and Technology/ ; 2017NZ0002-2//Fujian Provincial Department of Science and Technology/ ; },
abstract = {KEY MESSAGE: Piriformospora indica symbiosis promoted the growth and photosynthesis, and simultaneously enhanced the resistance against insect herbivory by regulating sporamin-dependent defense in sweet potato. Piriformospora indica (P. indica), a versatile endophytic fungus, promotes the growth and confers resistance against multiple stresses by root colonization in plant hosts. In this study, the effects of P. indica colonization on the growth, physiological change, and herbivore resistance of leaf-vegetable sweet potato cultivar were investigated. P. indica symbiosis significantly improved the biomass in both above- and under-ground parts of sweet potato plants. In comparison with the non-colonized plants, the content of photosynthetic pigments and the efficiency of photosynthesis were increased in P. indica-colonized sweet potato plants. Further investigation showed that the activity of catalase was enhanced in both leaves and roots of sweet potato plants after colonization, but ascorbate peroxidase, peroxidase, and superoxide dismutase were not enhanced. Furthermore, the interaction between P. indica and sweet potato plants also showed the biological function in jasmonic acid (JA)-mediated defense. The plants colonized by P. indica had greatly increased JA accumulation and defense gene expressions, including IbNAC1, IbbHLH3, IbpreproHypSys, and sporamin, leading to elevated trypsin inhibitory activity, which was consistent with a reduced Spodoptera litura performance when larvae fed on the leaves of P. indica-colonized sweet potato plants. The root symbiosis of P. indica is helpful for the plant promoting growth and development and has a strong function as resistance inducers against herbivore attack in sweet potato cultivation by regulating sporamin-dependent defense.},
}
@article {pmid33231304,
year = {2020},
author = {Chen, M and Bruisson, S and Bapaume, L and Darbon, G and Glauser, G and Schorderet, M and Reinhardt, D},
title = {VAPYRIN attenuates defence by repressing PR gene induction and localized lignin accumulation during arbuscular mycorrhizal symbiosis of Petunia hybrida.},
journal = {The New phytologist},
volume = {},
number = {},
pages = {},
doi = {10.1111/nph.17109},
pmid = {33231304},
issn = {1469-8137},
support = {31003A_169732//Schweizerischer Nationalfonds zur Förderung der Wissenschaftlichen Forschung/ ; },
abstract = {The intimate association of host and fungus in arbuscular mycorrhizal (AM) symbiosis can potentially trigger induction of host defence mechanisms against the fungus, implying that successful symbiosis requires suppression of defence. We addressed this phenomenon by using AM-defective vapyrin (vpy) mutants in Petunia hybrida, including a new allele (vpy-3) with a transposon insertion close to the ATG start codon. We explore whether abortion of fungal infection in vpy mutants is associated with the induction of defence markers, such as cell wall alterations, accumulation of reactive oxygen species (ROS), defence hormones and induction of pathogenesis-related (PR) genes. We show that vpy mutants exhibit a strong resistance against intracellular colonization, which is associated with the generation of cell wall appositions (papillae) with lignin impregnation at fungal entry sites, while no accumulation of defence hormones, ROS or callose was observed. Systematic analysis of PR gene expression revealed that several PR genes are induced in mycorrhizal roots of the wild-type, and even more in vpy plants. Some PR genes are induced exclusively in vpy mutants. Our results suggest that VPY is involved in avoiding or suppressing the induction of a cellular defence syndrome that involves localized lignin deposition and PR gene induction.},
}
@article {pmid33230800,
year = {2020},
author = {Virdi, JK and Pethe, P},
title = {Biomaterials Regulate Mechanosensors YAP/TAZ in Stem Cell Growth and Differentiation.},
journal = {Tissue engineering and regenerative medicine},
volume = {},
number = {},
pages = {},
doi = {10.1007/s13770-020-00301-4},
pmid = {33230800},
issn = {2212-5469},
support = {BT/PR28474/MED/31/393/2018//Department of Biotechnology , Ministry of Science and Technology/ ; },
abstract = {Tissue-resident stem cells are surrounded by a microenvironment known as 'stem cell niche' which is specific for each stem cell type. This niche comprises of cell-intrinsic and -extrinsic factors like biochemical and biophysical signals, which regulate stem cell characteristics and differentiation. Biochemical signals have been thoroughly studied however, the effect of biophysical signals on stem cell regulation is yet to be completely understood. Biomaterials have aided in addressing this issue since they can provide a defined and tuneable microenvironment resembling in vivo conditions. We review various biomaterials used in many studies which have shown a connection between biomaterial-generated mechanical signals and alteration in stem cell behaviour. Researchers probed to understand the mechanism of mechanotransduction and reported that the signals from the extracellular matrix regulate a transcription factor yes-associated protein (YAP)/transcriptional coactivator with PDZ-binding motif (TAZ), which is a downstream-regulator of the Hippo pathway and it transduces the mechanical signals inside the nucleus. We highlight the role of the YAP/TAZ as mechanotransducers in stem cell self-renewal and differentiation in response to substrate stiffness, also the possibility of mechanobiology as the emerging field of regenerative medicines and three-dimensional tissue printing.},
}
@article {pmid33229539,
year = {2020},
author = {Hu, H and Zakharov, PN and Peterson, OJ and Unanue, ER},
title = {Cytocidal macrophages in symbiosis with CD4 and CD8 T cells cause acute diabetes following checkpoint blockade of PD-1 in NOD mice.},
journal = {Proceedings of the National Academy of Sciences of the United States of America},
volume = {117},
number = {49},
pages = {31319-31330},
pmid = {33229539},
issn = {1091-6490},
support = {R01 AI114551/AI/NIAID NIH HHS/United States ; R01 DK058177/DK/NIDDK NIH HHS/United States ; },
abstract = {Autoimmune diabetes is one of the complications resulting from checkpoint blockade immunotherapy in cancer patients, yet the underlying mechanisms for such an adverse effect are not well understood. Leveraging the diabetes-susceptible nonobese diabetic (NOD) mouse model, we phenocopy the diabetes progression induced by programmed death 1 (PD-1)/PD-L1 blockade and identify a cascade of highly interdependent cellular interactions involving diabetogenic CD4 and CD8 T cells and macrophages. We demonstrate that exhausted CD8 T cells are the major cells that respond to PD-1 blockade producing high levels of IFN-γ. Most importantly, the activated T cells lead to the recruitment of monocyte-derived macrophages that become highly activated when responding to IFN-γ. These macrophages acquire cytocidal activity against β-cells via nitric oxide and induce autoimmune diabetes. Collectively, the data in this study reveal a critical role of macrophages in the PD-1 blockade-induced diabetogenesis, providing new insights for the understanding of checkpoint blockade immunotherapy in cancer and infectious diseases.},
}
@article {pmid33227009,
year = {2020},
author = {Guilhot, R and Fellous, S and Cohen, JE},
title = {Yeast facilitates the multiplication of Drosophila bacterial symbionts but has no effect on the form or parameters of Taylor's law.},
journal = {PloS one},
volume = {15},
number = {11},
pages = {e0242692},
pmid = {33227009},
issn = {1932-6203},
mesh = {Animals ; Bacteria/classification/*growth & development ; Drosophila melanogaster ; Larva/microbiology ; Symbiosis/*physiology ; Yeasts/classification/*growth & development ; },
abstract = {Interactions between microbial symbionts influence their demography and that of their hosts. Taylor's power law (TL)-a well-established relationship between population size mean and variance across space and time-may help to unveil the factors and processes that determine symbiont multiplications. Recent studies suggest pervasive interactions between symbionts in Drosophila melanogaster. We used this system to investigate theoretical predictions regarding the effects of interspecific interactions on TL parameters. We assayed twenty natural strains of bacteria in the presence and absence of a strain of yeast using an ecologically realistic set-up with D. melanogaster larvae reared in natural fruit. Yeast presence led to a small increase in bacterial cell numbers; bacterial strain identity largely affected yeast multiplication. The spatial version of TL held among bacterial and yeast populations with slopes of 2. However, contrary to theoretical prediction, the facilitation of bacterial symbionts by yeast had no detectable effect on TL's parameters. These results shed new light on the nature of D. melanogaster's symbiosis with yeast and bacteria. They further reveal the complexity of investigating TL with microorganisms.},
}
@article {pmid33226500,
year = {2020},
author = {Walther, C and Zumbülte, S and Faerber, CM and Wierichs, RJ and Meyer-Lueckel, H and Conrads, G and Henne, K and Esteves-Oliveira, M},
title = {Analysis of relative bacterial activity and lactate dehydrogenase gene expression of caries-associated bacteria in a site-specific natural biofilm: an ex vivo study.},
journal = {Clinical oral investigations},
volume = {},
number = {},
pages = {},
doi = {10.1007/s00784-020-03691-w},
pmid = {33226500},
issn = {1436-3771},
support = {(#39/17)//Medizinische Fakultät, RWTH Aachen University (DE)/ ; },
abstract = {OBJECTIVES: Detecting bacterial activity is considered a promising approach to monitor shifts from symbiosis to dysbiosis in oral microbiome. The present study aimed at investigating both the relative bacterial activity and the lactate dehydrogenase (ldh) gene expression of caries-associated bacteria in a site-specific natural biofilm.
MATERIAL AND METHODS: Sixty subjects (age, mean ± SE: 30.1 ± 1.4) were allocated to two groups: caries-free subjects (CF) or caries-active subjects (CA). CF presented one sound surface (CFS, n = 30). CA presented two donor sites: a cavitated caries lesion (CAC, n = 30) and a sound reference surface (CAS, n = 30). Real-time quantitative PCR (q-PCR) on species or genus level and total bacteria was performed targeting the 16S gene, the 16S rRNA, the ldh gene, and the ldh mRNA (increasing 16S ribosomal RNA copy numbers can function as an indicator of increased energy metabolism). As the 16S rRNA abundance represents the number of ribosomes, while the 16S gene abundance represents the number of genomes, the quotient of the relative abundances functions as a measure for the relative bacterial activity (%).
RESULTS: Both lactobacilli and S. mutans showed the highest relative bacterial activity in CAC ((mean ± SE) 218 ± 60% and 61 ± 16%, respectively) and the lowest values for both sound reference surfaces (69 ± 48%; 8 ± 3%). Significant differences were found between CAC and CAS as well as between CAC and CFS for both lactobacilli and S. mutans (p < 0.05). The ldh gene expression of lactobacilli and S. mutans only showed moderate values in CAC (1.90E+03 ± 2.11E+03; 2.08E+04 ± 4.44E+04 transcripts/μl) and CFS (2.04E+03 ± 2.74E+03; 8.16E+03 ± 6.64E+03 transcripts/μl); consequently no significant differences were detected.
Caries-associated bacteria (lactobacilli and S. mutans) showed the highest relative bacterial activity in plaque of cavitated lesions, the lowest in sound surfaces, allowing the detection of a significant activity shift in health and disease for caries-active patients. However, no significant differences in ldh gene expression could be determined.},
}
@article {pmid33226302,
year = {2020},
author = {Nouwen, N and Arrighi, JF and Gully, D and Giraud, E},
title = {RibBX of Bradyrhizobium ORS285 Plays an Important Role in Intracellular Persistence in Various Aeschynomene Host Plants.},
journal = {Molecular plant-microbe interactions : MPMI},
volume = {},
number = {},
pages = {MPMI07200209R},
doi = {10.1094/MPMI-07-20-0209-R},
pmid = {33226302},
issn = {0894-0282},
abstract = {Bradyrhizobium ORS285 forms a nitrogen-fixating symbiosis with both Nod factor (NF)-dependent and NF-independent Aeschynomene spp. The Bradyrhizobium ORS285 ribBA gene encodes for a putative bifunctional enzyme with 3,4-dihydroxybutanone phosphate (3,4-DHBP) synthase and guanosine triphosphate (GTP) cyclohydrolase II activities, catalyzing the initial steps in the riboflavin biosynthesis pathway. In this study, we show that inactivating the ribBA gene does not cause riboflavin auxotrophy under free-living conditions and that, as shown for RibBAs from other bacteria, the GTP cyclohydrolase II domain has no enzymatic activity. For this reason, we have renamed the annotated ribBA as ribBX. Because we were unable to identify other ribBA or ribA and ribB homologs in the genome of Bradyrhizobium ORS285, we hypothesize that the ORS285 strain can use unconventional enzymes or an alternative pathway for the initial steps of riboflavin biosynthesis. Inactivating ribBX has a drastic impact on the interaction of Bradyrhizobium ORS285 with many of the tested Aeschynomene spp. In these Aeschynomene spp., the ORS285 ribBX mutant is able to infect the plant host cells but the intracellular infection is not maintained and the nodules senesce early. This phenotype can be complemented by reintroduction of the 3,4-DHBP synthase domain alone. Our results indicate that, in Bradyrhizobium ORS285, the RibBX protein is not essential for riboflavin biosynthesis under free-living conditions and we hypothesize that its activity is needed to sustain riboflavin biosynthesis under certain symbiotic conditions.[Formula: see text] Copyright © 2020 The Author(s). This is an open access article distributed under the CC BY-NC-ND 4.0 International license.},
}
@article {pmid33224901,
year = {2020},
author = {Govender, Y and Chan, T and Yamamoto, HS and Budnik, B and Fichorova, RN},
title = {The Role of Small Extracellular Vesicles in Viral-Protozoan Symbiosis: Lessons From Trichomonasvirus in an Isogenic Host Parasite Model.},
journal = {Frontiers in cellular and infection microbiology},
volume = {10},
number = {},
pages = {591172},
pmid = {33224901},
issn = {2235-2988},
support = {R56 AI091889/AI/NIAID NIH HHS/United States ; RC1 AI086788/AI/NIAID NIH HHS/United States ; },
abstract = {The protozoan parasite Trichomonas vaginalis (TV), exclusively adapted to the human genital tract, is one of the most common sexually transmitted pathogens. Adding to the complexity of the host-pathogen interactions, the parasite harbors TV-specific endosymbiont viruses (Trichomonasvirus, TVV). It was reported that small extracellular vesicles (sEVs) released by TV play a role in host immunity; however, the role of the viral endosymbiosis in this process remained unknown. We hypothesized that the virus may offer evolutionary benefit to its protozoan host at least in part by altering the immunomodulatory properties of sEVs spreading from the site of infection to non-infected immune effector cells. We infected human vaginal epithelial cells, the natural host of the parasite, with TV natively harboring TVV and an isogenic derivative of the parasite cured from the viral infection. sEVs were isolated from vaginal cell culture 24 h post TV infection and from medium where the isogenic TV strains were cultured in the absence of the human host. sEVs from TVV-negative but not TVV-positive parasites cultured alone caused NF-κB activation and increase of IL-8 and RANTES expression by uterine endocervical cells, which provide innate immune defense at the gate to the upper reproductive tract. Similarly, mononuclear leukocytes increased their IL-8, IL-6 and TNF-α output in response to sEVs from virus-negative, but not isogenic virus-positive parasites, the latter exosomes being immunosuppressive in comparison to TV medium control. The same phenomenon of suppressed immunity induced by the TVV-positive compared to TVV-negative phenotype was seen when stimulating the leukocytes with sEVs originating from infected vaginal cultures. In addition, the sEVs from the TVV-positive infection phenotype suppressed immune signaling of a toll-like receptor ligand derived from mycoplasma, another frequent TV symbiont. Quantitative comparative proteome analysis of the secreted sEVs from virus-positive versus virus-negative TV revealed differential expression of two functionally uncharacterized proteins and five proteins involved in Zn binding, protein binding, electron transfer, transferase and catalytic activities. These data support the concept that symbiosis with viruses may provide benefit to the protozoan parasite by exploiting sEVs as a vehicle for inter-cellular communications and modifying their protein cargo to suppress host immune activation.},
}
@article {pmid33223597,
year = {2020},
author = {Pichler, G and Stöggl, W and Trippel, D and Candotto Carniel, F and Muggia, L and Ametrano, CG and Çimen, T and Holzinger, A and Tretiach, M and Kranner, I},
title = {Phytohormone release by three isolated lichen mycobionts and the effects of indole-3-acetic acid on their compatible photobionts.},
journal = {Symbiosis (Philadelphia, Pa.)},
volume = {82},
number = {1},
pages = {95-108},
pmid = {33223597},
issn = {0334-5114},
abstract = {Evidence is emerging that phytohormones represent key inter-kingdom signalling compounds supporting chemical communication between plants, fungi and bacteria. The roles of phytohormones for the lichen symbiosis are poorly understood, particularly in the process of lichenization, i.e. the key events which lead free-living microalgae and fungi to recognize each other, make physical contact and start developing a lichen thallus. Here, we studied cellular and extracellularly released phytohormones in three lichen mycobionts, Cladonia grayi, Xanthoria parietina and Tephromela atra, grown on solid medium, and the effects of indole-3-acetic acid (IAA) on their respective photobionts, Asterochloris glomerata, Trebouxia decolorans, Trebouxia sp. Using ultra-high-performance liquid chromatography coupled with tandem mass spectrometry (UHPLC-MS/MS) we found that mycobionts produced IAA, salicylic acid (SA) and jasmonic acid (JA). IAA represented the most abundant phytohormone produced and released by all mycobionts, whereas SA was released by X. parietina and T. atra, and JA was released by C. grayi only. With a half-life of 5.2 days, IAA degraded exponentially in solid BBM in dim light. When IAA was exogenously offered to the mycobionts' compatible photobionts at "physiological" concentrations (as released by their respective mycobionts and accumulated in the medium over seven days), the photobionts' water contents increased up to 4.4%. Treatment with IAA had no effects on the maximum quantum yield of photosystem II, dry mass, and the contents of photosynthetic pigments and α-tocopherol of the photobionts. The data presented may be useful for designing studies aimed at elucidating the roles of phytohormones in lichens.},
}
@article {pmid33222085,
year = {2020},
author = {Sgibnev, AV and Kremleva, EA},
title = {Inflammation Mediators Regulate the Microbiota Resistance to Adverse Factors.},
journal = {Bulletin of experimental biology and medicine},
volume = {170},
number = {1},
pages = {49-52},
doi = {10.1007/s10517-020-05002-5},
pmid = {33222085},
issn = {1573-8221},
abstract = {We studied the effects of IL-1β, IL-8, TNFα, and prostaglandin E2α in concentrations typically observed in health and during inflammation on the growth of vaginal microbiota and its resistance to factors inhibiting the synthesis of proteins, nucleic acids, and peptidoglycans. An increase in the cytokine levels, characteristic of inflammation, inhibits the growth of Lactobacillus population and improves its resistance to adverse factors. The growth of the population of opportunistic microorganisms (S. aureus, E. coli) is stimulated under these conditions, while their resistance to adverse factors decreases. Hence, it seems that the cytokines regulate the behavior of the host cells and of its bacterial symbionts.},
}
@article {pmid33220679,
year = {2020},
author = {Nilsson, JF and Castellani, LG and Draghi, WO and Mogro, EG and Wibberg, D and Winkler, A and Hansen, LH and Schlüter, A and Pühler, A and Kalinowski, J and Torres Tejerizo, GA and Pistorio, M},
title = {Global transcriptome analysis of Rhizobium favelukesii LPU83 in response to acid stress.},
journal = {FEMS microbiology ecology},
volume = {97},
number = {1},
pages = {},
doi = {10.1093/femsec/fiaa235},
pmid = {33220679},
issn = {1574-6941},
abstract = {Acidic environments naturally occur worldwide and inappropriate agricultural management may also cause acidification of soils. Low soil pH values are an important barrier in the plant-rhizobia interaction. Acidic conditions disturb the establishment of the efficient rhizobia usually used as biofertilizer. This negative effect on the rhizobia-legume symbiosis is mainly due to the low acid tolerance of the bacteria. Here, we describe the identification of relevant factors in the acid tolerance of Rhizobium favelukesii using transcriptome sequencing. A total of 1924 genes were differentially expressed under acidic conditions, with ∼60% underexpressed. Rhizobium favelukesii acid response mainly includes changes in the energy metabolism and protein turnover, as well as a combination of mechanisms that may contribute to this phenotype, including GABA and histidine metabolism, cell envelope modifications and reverse proton efflux. We confirmed the acid-sensitive phenotype of a mutant in the braD gene, which showed higher expression under acid stress. Remarkably, 60% of the coding sequences encoded in the symbiotic plasmid were underexpressed and we evidenced that a strain cured for this plasmid featured an improved performance under acidic conditions. Hence, this work provides relevant information in the characterization of genes associated with tolerance or adaptation to acidic stress of R. favelukesii.},
}
@article {pmid33220182,
year = {2020},
author = {Song, H and Hewitt, OH and Degnan, SM},
title = {Arginine Biosynthesis by a Bacterial Symbiont Enables Nitric Oxide Production and Facilitates Larval Settlement in the Marine-Sponge Host.},
journal = {Current biology : CB},
volume = {},
number = {},
pages = {},
doi = {10.1016/j.cub.2020.10.051},
pmid = {33220182},
issn = {1879-0445},
abstract = {Larval settlement and metamorphosis are regulated by nitric oxide (NO) signaling in a wide diversity of marine invertebrates.1-10 It is thus surprising that, in most invertebrates, the substrate for NO synthesis-arginine-cannot be biosynthesized but instead must be exogenously sourced.11 In the sponge Amphimedon queenslandica, vertically inherited proteobacterial symbionts in the larva are able to biosynthesize arginine.12,13 Here, we test the hypothesis that symbionts provide arginine to the sponge host so that nitric oxide synthase expressed in the larva can produce NO, which regulates metamorphosis,8 and the byproduct citrulline (Figure 1). First, we find support for an arginine-citrulline biosynthetic loop in this sponge larval holobiont by using stable isotope tracing. In symbionts, incorporated 13C-citrulline decreases as 13C-arginine increases, consistent with the use of exogenous citrulline for arginine synthesis. In contrast, 13C-citrulline accumulates in larvae as 13C-arginine decreases, demonstrating the uptake of exogenous arginine and its conversion to NO and citrulline. Second, we show that, although Amphimedon larvae can derive arginine directly from seawater, normal settlement and metamorphosis can occur in artificial sea water lacking arginine. Together, these results support holobiont complementation of the arginine-citrulline loop and NO biosynthesis in Amphimedon larvae, suggesting a critical role for bacterial symbionts in the development of this marine sponge. Given that NO regulates settlement and metamorphosis in diverse animal phyla1-10 and arginine is procured externally in most animals,11 we propose that symbionts might play an equally critical regulatory role in this essential life cycle transition in other metazoans.},
}
@article {pmid33219668,
year = {2020},
author = {Shin, J and Marx, H and Richards, A and Vaneechoutte, D and Jayaraman, D and Maeda, J and Chakraborty, S and Sussman, M and Vandepoele, K and Ané, JM and Coon, J and Roy, S},
title = {A network-based comparative framework to study conservation and divergence of proteomes in plant phylogenies.},
journal = {Nucleic acids research},
volume = {},
number = {},
pages = {},
doi = {10.1093/nar/gkaa1041},
pmid = {33219668},
issn = {1362-4962},
abstract = {Comparative functional genomics offers a powerful approach to study species evolution. To date, the majority of these studies have focused on the transcriptome in mammalian and yeast phylogenies. Here, we present a novel multi-species proteomic dataset and a computational pipeline to systematically compare the protein levels across multiple plant species. Globally we find that protein levels diverge according to phylogenetic distance but is more constrained than the mRNA level. Module-level comparative analysis of groups of proteins shows that proteins that are more highly expressed tend to be more conserved. To interpret the evolutionary patterns of conservation and divergence, we develop a novel network-based integrative analysis pipeline that combines publicly available transcriptomic datasets to define co-expression modules. Our analysis pipeline can be used to relate the changes in protein levels to different species-specific phenotypic traits. We present a case study with the rhizobia-legume symbiosis process that supports the role of autophagy in this symbiotic association.},
}
@article {pmid33219377,
year = {2020},
author = {Huo, H and Wang, X and Liu, Y and Chen, J and Wei, G},
title = {A Nod factor- and type III secretion system-dependent manner for Robinia pseudoacacia to establish symbiosis with Mesorhizobium amorphae CCNWGS0123.},
journal = {Tree physiology},
volume = {},
number = {},
pages = {},
doi = {10.1093/treephys/tpaa160},
pmid = {33219377},
issn = {1758-4469},
abstract = {Under nitrogen-limiting conditions, symbiotic nodulation promotes the growth of legume plants via the fixation of atmospheric nitrogen to ammonia by rhizobia in root nodules. The rhizobial Nod factor (NF) and type III secretion system (T3SS) are two key signaling pathways for establishing the legume-rhizobium symbiosis. However, whether NF signaling is involved in the nodulation of Robinia pseudoacacia and Mesorhizobium amorphae CCNWGS0123, and its symbiotic differences compared to T3SS signaling remain unclear. Therefore, to elucidate the function of NF signaling in nodulation, we mutated nodC in M. amorphae CCNWGS0123, which aborted NF synthesis. Compared to the plants inoculated with the wild type strain, the plants inoculated with the NF-deficient strain exhibited shorter shoots with etiolated leaves. These phenotypic characteristics were similar to those of the plants inoculated with the T3SS-deficient strain, which served as a nod- (non-effective nodulation) control. Both the plants inoculated with the NF- and T3SS-deficient strains formed massive root hair swellings, but no normal infection threads were detected. Sections of the nodules showed that inoculation with the NF- and T3SS-deficient strains induced small, white bumps without any rhizobia inside. Analyzing the accumulation of six plant hormones and the expression of ten plant genes indicated that the NF- and T3SS-deficient strains activated plant defense reactions while suppressing plant symbiotic signaling during the perception and nodulation processes. The requirement for NF signaling appeared to be conserved in two other leguminous trees that can establish symbiosis with M. amorphae CCNWGS0123. In contrast, the function of the T3SS might differ among species, even within the same subfamily (Faboideae). Overall, this work demonstrated that nodulation of R. pseudoacacia and M. amorphae CCNWGS0123 was both NF and T3SS dependent.},
}
@article {pmid33219283,
year = {2020},
author = {Binet, MN and Marchal, C and Lipuma, J and Geremia, RA and Bagarri, O and Candaele, B and Fraty, D and David, B and Perigon, S and Barbreau, V and Mouhamadou, B},
title = {Plant health status effects on arbuscular mycorrhizal fungi associated with Lavandula angustifolia and Lavandula intermedia infected by Phytoplasma in France.},
journal = {Scientific reports},
volume = {10},
number = {1},
pages = {20305},
pmid = {33219283},
issn = {2045-2322},
abstract = {We investigated root communities of arbuscular mycorrhizal fungi (AMF) in relation to lavender (Lavandula angustifolia) and lavandin (Lavandula intermedia) health status from organic and conventional fields affected by Phytoplasma infection. The intensity of root mycorrhizal colonization was significantly different between diseased and healthy plants and was higher in the latter regardless of agricultural practice. This difference was more pronounced in lavender. The root AMF diversity was influenced by the plant health status solely in lavender and only under the conventional practice resulting in an increase in the AMF abundance and richness. The plant health status did not influence the distribution of root AMF communities in lavandin unlike its strong impact in lavender in both agricultural practices. Finally, among the most abundant molecular operational taxonomic units (MOTUs), four different MOTUs for each plant species were significantly abundant in the roots of healthy lavender and lavandin in either agricultural practice. Our study demonstrated that the plant health status influences root colonization and can influence the diversity and distribution of root AMF communities. Its effects vary according to plant species, can be modified by agricultural practices and allow plants to establish symbiosis with specific AMF species.},
}
@article {pmid33218179,
year = {2020},
author = {Tavarini, S and Clemente, C and Bender, C and Angelini, LG},
title = {Health-Promoting Compounds in Stevia: The Effect of Mycorrhizal Symbiosis, Phosphorus Supply and Harvest Time.},
journal = {Molecules (Basel, Switzerland)},
volume = {25},
number = {22},
pages = {},
pmid = {33218179},
issn = {1420-3049},
abstract = {This work aimed to establish the synergic role of arbuscular mycorrhizal fungi (AMF) symbiosis, phosphorus (P) fertilization and harvest time on the contents of stevia secondary metabolites. Consequently, steviol glycosides (SVglys) concentration and profile, total phenols and flavonoids as well as antioxidant assays, have been assessed in inoculated and no-inoculated plants, grown with or without P supply and collected at different growth stages(69, 89 and 123 days after transplanting).The obtained results suggest that the synthesis of stevia secondary metabolites is induced and/or modulated by all the investigated variability factors. In particular, AMF symbiosis promoted total SVglys content and positively influenced the concentration of some minor compounds (steviolbioside, dulcoside A and rebaudioside B), indicating a clear effect of mycorrhizal inoculation on SVglys biosynthetic pathway. Interestingly, only the mycorrhizal plants were able to synthesize rebaudioside B. In addition, P supply provided the highest levels of total phenols and flavonoids at leaf level, together with the maximum in vitro antioxidant activities (FRAP and ORAC). Finally, the harvest time carried out during the full vegetative phase enhanced the entire composition of the phytocomplex (steviolbioside, dulcoside A, stevioside, rebaudioside A, B, C. total phenols and flavonoids). Moreover, polyphenols and SVglys appeared to be the main contributors to the in vitro antioxidant capacity, while only total phenols mostly contributed to the cellular antioxidant activity (CAA). These findings provide original information about the role played by AMF in association with P supply, in modulating the accumulation of bioactive compounds during stevia growth. At the cultivation level, the control of these preharvest factors, together with the most appropriate harvest time, can be used as tools for improving the nutraceutical value of raw material, with particular attention to its exploitation as functional ingredient for food and dietary supplements and cosmetics.},
}
@article {pmid33216794,
year = {2020},
author = {Garcia, K and Guerrero-Galán, C and Frank, HER and Haider, MZ and Delteil, A and Conéjéro, G and Lambilliotte, R and Fizames, C and Sentenac, H and Zimmermann, SD},
title = {Fungal Shaker-like channels beyond cellular K+ homeostasis: A role in ectomycorrhizal symbiosis between Hebeloma cylindrosporum and Pinus pinaster.},
journal = {PloS one},
volume = {15},
number = {11},
pages = {e0242739},
pmid = {33216794},
issn = {1932-6203},
abstract = {Potassium (K+) acquisition, translocation and cellular homeostasis are mediated by various membrane transport systems in all organisms. We identified and described an ion channel in the ectomycorrhizal fungus Hebeloma cylindrosporum (HcSKC) that harbors features of animal voltage-dependent Shaker-like K+ channels, and investigated its role in both free-living hyphae and symbiotic conditions. RNAi lines affected in the expression of HcSKC were produced and used for in vitro mycorrhizal assays with the maritime pine as host plant, under standard or low K+ conditions. The adaptation of H. cylindrosporum to the downregulation of HcSKC was analyzed by qRT-PCR analyses for other K+-related transport proteins: the transporters HcTrk1, HcTrk2, and HcHAK, and the ion channels HcTOK1, HcTOK2.1, and HcTOK2.2. Downregulated HcSKC transformants displayed greater K+ contents at standard K+ only. In such conditions, plants inoculated with these transgenic lines were impaired in K+ nutrition. Taken together, these results support the hypothesis that the reduced expression of HcSKC modifies the pool of fungal K+ available for the plant and/or affects its symbiotic transfer to the roots. Our study reveals that the maintenance of K+ transport in H. cylindrosporum, through the regulation of HcSKC expression, is required for the K+ nutrition of the host plant.},
}
@article {pmid33214705,
year = {2021},
author = {Qiu, X and Macchietto, MG and Liu, X and Lu, Y and Ma, Y and Guo, H and Saqui-Salces, M and Bernlohr, DA and Chen, C and Shen, S and Chen, X},
title = {Identification of gut microbiota and microbial metabolites regulated by an antimicrobial peptide lipocalin 2 in high fat diet-induced obesity.},
journal = {International journal of obesity (2005)},
volume = {45},
number = {1},
pages = {143-154},
pmid = {33214705},
issn = {1476-5497},
support = {R01 DK123042/DK/NIDDK NIH HHS/United States ; },
abstract = {Lipocalin 2 (Lcn2), as an antimicrobial peptide is expressed in intestine, and the upregulation of intestinal Lcn2 has been linked to inflammatory bowel disease. However, the role of Lcn2 in shaping gut microbiota during diet-induced obesity (DIO) remains unknown. We found that short-term high fat diet (HFD) feeding strongly stimulates intestinal Lcn2 expression and secretion into the gut lumen. As the HFD feeding prolongs, fecal Lcn2 levels turn to decrease. Lcn2 deficiency accelerates the development of HFD-induced intestinal inflammation and microbiota dysbiosis. Moreover, Lcn2 deficiency leads to the remodeling of microbiota-derived metabolome, including decreased production of short-chain fatty acids (SCFAs) and SCFA-producing microbes. Most importantly, we have identified Lcn2-targeted bacteria and microbiota-derived metabolites that potentially play roles in DIO and metabolic dysregulation. Correlation analyses suggest that Lcn2-targeted Dubosiella and Angelakisella have a novel role in regulating SCFAs production and obesity. Our results provide a novel mechanism involving Lcn2 as an antimicrobial host factor in the control of gut microbiota symbiosis during DIO.},
}
@article {pmid33214187,
year = {2020},
author = {Durán, D and Albareda, M and Marina, A and García, C and Ruiz-Argüeso, T and Palacios, J},
title = {Proteome analysis reveals a significant host-specific response in Rhizobium leguminosarum bv viciae endosymbiotic cells.},
journal = {Molecular & cellular proteomics : MCP},
volume = {},
number = {},
pages = {},
doi = {10.1074/mcp.RA120.002276},
pmid = {33214187},
issn = {1535-9484},
abstract = {The Rhizobium-legume symbiosis is a beneficial interaction in which the bacterium converts atmospheric nitrogen into ammonia and delivers it to the plant in exchange for carbon compounds. This symbiosis implies the adaptation of bacteria to live inside host plant cells. In this work we apply RP-LC-MS/MS and iTRAQ techniques to study the proteomic profile of endosymbiotic cells (bacteroids) induced by Rhizobium leguminosarum bv viciae strain UPM791 in legume nodules. Nitrogenase subunits, tricarboxylic acid cycle enzymes, and stress response proteins are amongst the most abundant from over one thousand rhizobial proteins identified in pea (Pisum sativum) bacteroids. Comparative analysis of bacteroids induced in pea and in lentil (Lens culinaris)nodules revealed the existence of a significant host-specific differential response affecting dozens of bacterial proteins, including stress-related proteins, transcriptional regulators, and proteins involved in the carbon and nitrogen metabolisms. A mutant affected in one of these proteins, homologous to a GntR-like transcriptional regulator, showed a symbiotic performance significantly impaired in symbiosis with pea, but not with lentil plants. Analysis of the proteomes of bacteroids isolated from both hosts also revealed the presence of different sets of plant-derived nodule-specific cysteine rich (NCR) peptides, indicating that the endosymbiotic bacteria find a host-specific cocktail of chemical stressors inside the nodule. By studying variations of the bacterial response to different plant cell environments we will be able to identify specific limitations imposed by the host that might give us clues for the improvement of rhizobial performance.},
}
@article {pmid33211006,
year = {2020},
author = {Ramírez-Flores, MR and Perez-Limon, S and Li, M and Barrales-Gamez, B and Albinsky, D and Paszkowski, U and Olalde-Portugal, V and Sawers, RJ},
title = {The genetic architecture of host response reveals the importance of arbuscular mycorrhizae to maize cultivation.},
journal = {eLife},
volume = {9},
number = {},
pages = {},
pmid = {33211006},
issn = {2050-084X},
support = {Impact of native arbuscular mycorrhizal fungi on maize performance (Nº 62, 2016-2018)//La Comisión Nacional para el Conocimiento y Uso de la Biodiversidad (CONABIO), Mexico/International ; Ph.D. scholarship//Consejo Nacional de Ciencia y Tecnología (CONACYT), Mexico/International ; Hatch Appropriations under Project #PEN04734 and Accession #1021929//U.S. Department of Agriculture/International ; Engineering the Nitrogen Symbiosis for Africa (ENSA)//Bill & Melinda Gates Foundation and the Foreign, Commonwealth & Development Office (FCDO)/International ; },
abstract = {Arbuscular mycorrhizal fungi (AMF) are ubiquitous in cultivated soils, forming symbiotic relationships with the roots of major crop species. Studies in controlled conditions have demonstrated the potential of AMF to enhance the growth of host plants. However, it is difficult to estimate the actual benefit in the field, not least because of the lack of suitable AMF-free controls. Here we implement a novel strategy using the selective incorporation of AMF-resistance into a genetic mapping population to evaluate maize response to AMF. We found AMF to account for about one-third of the grain production in a medium input field, as well as to affect the relative performance of different plant genotypes. Characterization of the genetic architecture of the host response indicated a trade-off between mycorrhizal dependence and benefit. We identified several QTL linked to host benefit, supporting the feasibility of breeding crops to maximize profit from symbiosis with AMF.},
}
@article {pmid33210234,
year = {2020},
author = {Abdulsalam, O and Wagner, K and Wirth, S and Kunert, M and David, A and Kallenbach, M and Boland, W and Kothe, E and Krause, K},
title = {Phytohormones and volatile organic compounds, like geosmin, in the ectomycorrhiza of Tricholoma vaccinum and Norway spruce (Picea abies).},
journal = {Mycorrhiza},
volume = {},
number = {},
pages = {},
doi = {10.1007/s00572-020-01005-2},
pmid = {33210234},
issn = {1432-1890},
abstract = {The ectomycorrhizospheric habitat contains a diverse pool of organisms, including the host plant, mycorrhizal fungi, and other rhizospheric microorganisms. Different signaling molecules may influence the ectomycorrhizal symbiosis. Here, we investigated the potential of the basidiomycete Tricholoma vaccinum to produce communication molecules for the interaction with its coniferous host, Norway spruce (Picea abies). We focused on the production of volatile organic compounds and phytohormones in axenic T. vaccinum cultures, identified the potential biosynthesis genes, and investigated their expression by RNA-Seq analyses. T. vaccinum released volatiles not usually associated with fungi, like limonene and β-barbatene, and geosmin. Using stable isotope labeling, the biosynthesis of geosmin was elucidated. The geosmin biosynthesis gene ges1 of T. vaccinum was identified, and up-regulation was scored during mycorrhiza, while a different regulation was seen with mycorrhizosphere bacteria. The fungus also released the volatile phytohormone ethylene and excreted salicylic and abscisic acid as well as jasmonates into the medium. The tree excreted the auxin, indole-3-acetic acid, and its biosynthesis intermediate, indole-3-acetamide, as well as salicylic acid with its root exudates. These compounds could be shown for the first time in exudates as well as in soil of a natural ectomycorrhizospheric habitat. The effects of phytohormones present in the mycorrhizosphere on hyphal branching of T. vaccinum were assessed. Salicylic and abscisic acid changed hyphal branching in a concentration-dependent manner. Since extensive branching is important for mycorrhiza establishment, a well-balanced level of mycorrhizospheric phytohormones is necessary. The regulation thus can be expected to contribute to an interkingdom language.},
}
@article {pmid33209854,
year = {2020},
author = {Shigli, K and Nayak, SS and Menon, K and Jirge, VL and Gali, S and Patil, M and Limaye, T and Ambali, A},
title = {Dietary counseling: A requisite in geriatric prosthodontics.},
journal = {Journal of family medicine and primary care},
volume = {9},
number = {9},
pages = {5081-5082},
pmid = {33209854},
issn = {2249-4863},
}
@article {pmid33209293,
year = {2020},
author = {Melo Clavijo, J and Frankenbach, S and Fidalgo, C and Serôdio, J and Donath, A and Preisfeld, A and Christa, G},
title = {Identification of scavenger receptors and thrombospondin-type-1 repeat proteins potentially relevant for plastid recognition in Sacoglossa.},
journal = {Ecology and evolution},
volume = {10},
number = {21},
pages = {12348-12363},
pmid = {33209293},
issn = {2045-7758},
abstract = {Functional kleptoplasty is a photosymbiotic relationship, in which photosynthetically active chloroplasts serve as an intracellular symbiont for a heterotrophic host. Among Metazoa, functional kleptoplasty is only found in marine sea slugs belonging to the Sacoglossa and recently described in Rhabdocoela worms. Although functional kleptoplasty has been intensively studied in Sacoglossa, the fundamentals of the specific recognition of the chloroplasts and their subsequent incorporation are unknown. The key to ensure the initiation of any symbiosis is the ability to specifically recognize the symbiont and to differentiate a symbiont from a pathogen. For instance, in photosymbiotic cnidarians, several studies have shown that the host innate immune system, in particular scavenger receptors (SRs) and thrombospondin-type-1 repeat (TSR) protein superfamily, is playing a major role in the process of recognizing and differentiating symbionts from pathogens. In the present study, SRs and TSRs of three Sacoglossa sea slugs, Elysia cornigera, Elysia timida, and Elysia chlorotica, were identified by translating available transcriptomes into potential proteins and searching for receptor specific protein and/or transmembrane domains. Both receptors classes are highly diverse in the slugs, and many new domain arrangements for each receptor class were found. The analyses of the gene expression of these three species provided a set of species-specific candidate genes, that is, SR-Bs, SR-Es, C-type lectins, and TSRs, that are potentially relevant for the recognition of kleptoplasts. The results set the base for future experimental studies to understand if and how these candidate receptors are indeed involved in chloroplast recognition.},
}
@article {pmid33207834,
year = {2020},
author = {Wilkes, TI and Warner, DJ and Edmonds-Brown, V and Davies, KG},
title = {Species-Specific Interactions of Bacillus Innocula and Arbuscular Mycorrhizal Fungi Symbiosis with Winter Wheat.},
journal = {Microorganisms},
volume = {8},
number = {11},
pages = {},
pmid = {33207834},
issn = {2076-2607},
support = {01092017//SALISBURY CHARITABLE TRUST/ ; },
abstract = {Arbuscular mycorrhizal (AM) fungi establish close interactions with host plants, an estimated 80% of vascular plant species. The host plant receives additional soil bound nutrients that would otherwise not be available. Other components of the microbiome, such as rhizobacteria, may influence interactions between AM fungi and the host plant. Within a commercial arable crop selected rhizobacteria in combination with AM fungi may benefit crop yields. The precise nature of interactions between rhizobacteria and AM fungi in a symbiotic relationship overall requires greater understanding. The present study aims to assess this relationship by quantifying: (1) AM fungal intracellular root structures (arbuscules) and soil glomalin as an indicator of AM fungal growth; and (2) root length and tiller number as a measure of crop growth, in response to inoculation with one of three species of Bacillus: B. amyloliquefaciences, B. pumilis, or B. subtilis. The influence of soil management, conventional (CT) or zero tillage (ZT) was a further variable evaluated. A significant (p < 0.0001) species-specific impact on the number of quantifiable AM fungal arbuscules was observed. The inoculation of winter wheat (Triticum aestivum) with B. amyloliquefaciences had a positive impact on AM fungal symbiosis, as indicated by an average of 3226 arbuscules per centimetre of root tissue. Bacillus subtilis increased root length significantly (p < 0.01) but decreased fungal symbiosis (p < 0.01). The inoculation of field soils altered the concentration of glomalin, an indicator of AM fungal growth, significantly (p < 0.00001) for each tillage treatment. The greatest increase was associated with B. amyloliquefaciences for both CT (p < 0.0001) and ZT (p < 0.00001). Bacillus subtilis reduced measured glomalin significantly in both tillage treatments (p < 0.0001 and p < 0.00001 for CT and ZT respectively). The interaction between rhizobacteria and AM fungi is variable, being beneficial or detrimental depending on species. This relationship was evident in both tillage treatments and has important implications for maximizing symbiosis in the crop plant-microbiome present in agricultural systems.},
}
@article {pmid33204029,
year = {2020},
author = {Kumar, PR and Moore, JA and Bowles, KM and Rushworth, SA and Moncrieff, MD},
title = {Mitochondrial oxidative phosphorylation in cutaneous melanoma.},
journal = {British journal of cancer},
volume = {},
number = {},
pages = {},
doi = {10.1038/s41416-020-01159-y},
pmid = {33204029},
issn = {1532-1827},
abstract = {The Warburg effect in tumour cells is associated with the upregulation of glycolysis to generate ATP, even under normoxic conditions and the presence of fully functioning mitochondria. However, scientific advances made over the past 15 years have reformed this perspective, demonstrating the importance of oxidative phosphorylation (OXPHOS) as well as glycolysis in malignant cells. The metabolic phenotypes in melanoma display heterogeneic dynamism (metabolic plasticity) between glycolysis and OXPHOS, conferring a survival advantage to adapt to harsh conditions and pathways of chemoresistance. Furthermore, the simultaneous upregulation of both OXPHOS and glycolysis (metabolic symbiosis) has been shown to be vital for melanoma progression. The tumour microenvironment (TME) has an essential supporting role in promoting progression, invasion and metastasis of melanoma. Mesenchymal stromal cells (MSCs) in the TME show a symbiotic relationship with melanoma, protecting tumour cells from apoptosis and conferring chemoresistance. With the significant role of OXPHOS in metabolic plasticity and symbiosis, our review outlines how mitochondrial transfer from MSCs to melanoma tumour cells plays a key role in melanoma progression and is the mechanism by which melanoma cells regain OXPHOS capacity even in the presence of mitochondrial mutations. The studies outlined in this review indicate that targeting mitochondrial trafficking is a potential novel therapeutic approach for this highly refractory disease.},
}
@article {pmid33203688,
year = {2020},
author = {Zhou, F and Xu, L and Wu, X and Zhao, X and Liu, M and Zhang, X},
title = {Symbiotic Bacterium-Derived Organic Acids Protect Delia antiqua Larvae from Entomopathogenic Fungal Infection.},
journal = {mSystems},
volume = {5},
number = {6},
pages = {},
pmid = {33203688},
issn = {2379-5077},
abstract = {Colonization resistance, i.e., the protective effects of associated microbiota for the animal host against pathogen infection, has been studied widely over the last 100 years. However, few molecules mediating colonization resistance have been identified. In the symbiosis formed by Delia antiqua and its associated microbes, six bacteria protect larvae from infection with the entomopathogen Beauveria bassiana, providing an ideal model to investigate the chemical mechanism for colonization resistance. Subsequently using this symbiotic system, we first compared effects of the six bacterial species, and one control bacterium (Klebsiella oxytoca) that showed no antifungal effects, on B. bassiana and its infection of D. antiqua Second, metabolomic profiles of the six bacteria and K. oxytoca were compared to identify candidate metabolites that may prevent infection. Third, the concentrations of candidate metabolites in situ from axenic and nonaxenic larvae were determined. Finally, effects of artificial metabolite cocktails on B.bassiana and its infection of D. antiqua larvae were determined. Results showed that compared to K. oxytoca, the six bacteria produced a metabolite cocktail showing inhibitory effects on conidial germination, mycelial growth of B.bassiana, and fungal infection. Our work revealed novel molecules that mediate colonization resistance, which could help in developing chemical mechanisms of colonization resistance. Moreover, this work may aid in discovery and expansion of new bioactive antibiotics, promoting development of prophylactic and therapeutic approaches for treating infectious diseases.IMPORTANCE The protection of associated microbiota for their animal hosts against pathogen infection has been studied widely over the last 100 years. However, how those microbes protect the animal host remains unclear. In former studies, body surface microbes of one insect, Delia antiqua, protected the insect larvae from infection with the entomopathogen Beauveria bassiana By comparing the metabolites produced by microbes that protect the insect and microbes that cannot protect the insect, the question of how the microbes protect the insect is answered. It turns out that body surface bacteria produce a metabolite cocktail that inhibits colonization of B.bassiana and consequently protects the insect. This work reveals novel molecules with antifungal activity, which may aid in discovery and expansion of new prophylactic and therapeutic natural chemicals for treating infectious diseases.},
}
@article {pmid33201434,
year = {2020},
author = {Ci, D and Tang, Z and Ding, H and Cui, L and Zhang, G and Li, S and Dai, L and Qin, F and Zhang, Z and Yang, J and Xu, Y},
title = {The synergy effect of arbuscular mycorrhizal fungi symbiosis and exogenous calcium on bacterial community composition and growth performance of peanut (Arachis hypogaea L.) in saline alkali soil.},
journal = {Journal of microbiology (Seoul, Korea)},
volume = {},
number = {},
pages = {},
doi = {10.1007/s12275-021-0317-3},
pmid = {33201434},
issn = {1976-3794},
abstract = {Peanut (Arachis hypogaea. L) is an important oil seed crop. Both arbuscular mycorrhizal fungi (AMF) symbiosis and calcium (Ca2+) application can ameliorate the impact of saline soil on peanut production, and the rhizosphere bacterial communities are also closely correlated with peanut salt tolerance; however, whether AMF and Ca2+ can withstand high-salinity through or partially through modulating rhizosphere bacterial communities is unclear. Here, we used the rhizosphere bacterial DNA from saline alkali soil treated with AMF and Ca2+ alone or together to perform high-throughput sequencing of 16S rRNA genes. Taxonomic analysis revealed that AMF and Ca2+ treatment increased the abundance of Proteobacteria and Firmicutes at the phylum level. The nitrogen-fixing bacterium Sphingomonas was the dominant genus in these soils at the genus level, and the soil invertase and urease activities were also increased after AMF and Ca2+ treatment, implying that AMF and Ca2+ effectively improved the living environment of plants under salt stress. Moreover, AMF combined with Ca2+ was better than AMF or Ca2+ alone at altering the bacterial structure and improving peanut growth in saline alkali soil. Together, AMF and Ca2+ applications are conducive to peanut salt adaption by regulating the bacterial community in saline alkali soil.},
}
@article {pmid33200348,
year = {2020},
author = {Paparokidou, C and Leake, JR and Beerling, DJ and Rolfe, SA},
title = {Phosphate availability and ectomycorrhizal symbiosis with Pinus sylvestris have independent effects on the Paxillus involutus transcriptome.},
journal = {Mycorrhiza},
volume = {},
number = {},
pages = {},
doi = {10.1007/s00572-020-01001-6},
pmid = {33200348},
issn = {1432-1890},
support = {CDREG, 322998//H2020 European Research Council/ ; },
abstract = {Many plant species form symbioses with ectomycorrhizal fungi, which help them forage for limiting nutrients in the soil such as inorganic phosphate (Pi). The transcriptional responses to symbiosis and nutrient-limiting conditions in ectomycorrhizal fungal hyphae, however, are largely unknown. An artificial system was developed to study ectomycorrhizal basidiomycete Paxillus involutus growth in symbiosis with its host tree Pinus sylvestris at different Pi concentrations. RNA-seq analysis was performed on P. involutus hyphae growing under Pi-limiting conditions, either in symbiosis or alone. We show that Pi starvation and ectomycorrhizal symbiosis have an independent effect on the P. involutus transcriptome. Notably, low Pi availability induces expression of newly identified putative high-affinity Pi transporter genes, while reducing the expression of putative organic acid transporters. Additionally, low Pi availability induces a close transcriptional interplay between P and N metabolism. GTP-related signalling was found to have a positive effect in the maintenance of ectomycorrhizal symbiosis, whereas multiple putative cytochrome P450 genes were found to be downregulated, unlike arbuscular mycorrhizal fungi. We provide the first evidence of global transcriptional changes induced by low Pi availability and ectomycorrhizal symbiosis in the hyphae of P. involutus, revealing both similarities and differences with better-characterized arbuscular mycorrhizal fungi.},
}
@article {pmid33200347,
year = {2020},
author = {de Oliveira, IF and Simeone, MLF and de Guimarães, CC and Garcia, NS and Schaffert, RE and de Sousa, SM},
title = {Sorgoleone concentration influences mycorrhizal colonization in sorghum.},
journal = {Mycorrhiza},
volume = {},
number = {},
pages = {},
doi = {10.1007/s00572-020-01006-1},
pmid = {33200347},
issn = {1432-1890},
support = {12.14.10.003.00.00//Embrapa/ ; },
abstract = {The association between arbuscular mycorrhizal fungi (AMF) and sorghum, the fifth most cultivated cereal in the world and a staple food for many countries, is relevant to improving phosphorus (P) absorption. The importance of root exudation as a signal for the symbiosis has been shown for several species, but a complete understanding of the signaling molecules involved in the mycorrhizal symbiosis signaling pathway has not yet been elucidated. In this context, we investigated the effect of sorgoleone, one of the most studied allelochemicals and a predominant compound of root exudates in sorghum, on AMF colonization and consequently P uptake and plant growth on a sorghum genotype. The sorghum genotype P9401 presents low endogenous sorgoleone content, and when it was inoculated with Rhizophagus clarus together with 5 and 10 µM sorgoleone, mycorrhizal colonization was enhanced. A significant enhancement of mycorrhizal colonization and an increase of P content and biomass were observed when R. clarus was inoculated together with 20 µM sorgoleone. Thus, our results indicate that sorgoleone influences mycorrhizal colonization, but the mechanisms by which it does so still need to be revealed.},
}
@article {pmid33197827,
year = {2021},
author = {de Souza Campos, PM and Borie, F and Cornejo, P and Meier, S and López-Ráez, JA and López-Garcia, Á and Seguel, A},
title = {Wheat root trait plasticity, nutrient acquisition and growth responses are dependent on specific arbuscular mycorrhizal fungus and plant genotype interactions.},
journal = {Journal of plant physiology},
volume = {256},
number = {},
pages = {153297},
doi = {10.1016/j.jplph.2020.153297},
pmid = {33197827},
issn = {1618-1328},
abstract = {This study aimed to examine how interactions at both plant genotype and arbuscular mycorrhizal fungus species levels affected the expression of root traits and the subsequent effect on plant nutrition and growth. We used two wheat cultivars with contrasting phosphorus (P) acquisition efficiencies (Tukan and Crac) and two arbuscular mycorrhizal (AM) fungi (Rhizophagus intraradices and Claroideoglomus claroideum). Plant growth, as well as morphological and architectural root traits, were highly dependent on the myco-symbiotic partner in the case of the less P-acquisition efficient cultivar Tukan, with mycorrhizal responses ranging from -45 to 54 % with respect to non-mycorrhizal plants. Meanwhile, these responses were between only -7 and 5 % in the P-acquisition efficient cultivar Crac. The AM fungal species produced contrasting mechanisms in the improvement of plant nutrition and root trait responses. Colonization by R. intraradices increased Ca accumulation, regardless of the cultivar, but reduced root growth on Tukan plants. On the other hand, C. claroideum increased P content in both cultivars, with a concomitant increase in root growth and diffusion-based nutrient acquisition by Tukan. Moreover, plants in symbiosis with R. intraradices showed greater organic acid concentration in their rhizosphere compared to C. claroideum-colonized plants, especially Tukan (24 and 35 % more citrate and oxalate, respectively). Our results suggest that the responses in plant-AM fungal interactions related to nutrient dynamics are highly influenced at the fungus level and also by intra-specific variations in root traits at the genotype level, while growth responses related to improved nutrition depend on plant intrinsic acquisition efficiency.},
}
@article {pmid33194832,
year = {2020},
author = {Wood, TE and Aksoy, E and Hachani, A},
title = {From Welfare to Warfare: The Arbitration of Host-Microbiota Interplay by the Type VI Secretion System.},
journal = {Frontiers in cellular and infection microbiology},
volume = {10},
number = {},
pages = {587948},
pmid = {33194832},
issn = {2235-2988},
abstract = {The health of mammals depends on a complex interplay with their microbial ecosystems. Compartments exposed to external environments such as the mucosal surfaces of the gastrointestinal tract accommodate the gut microbiota, composed by a wide range of bacteria. The gut microbiome confers benefits to the host, including expansion of metabolic potential and the development of an immune system that can robustly protect from external and internal insults. The cooperation between gut microbiome and host is enabled in part by the formation of partitioned niches that harbor diverse bacterial phyla. Bacterial secretion systems are commonly employed to manipulate the composition of these local environments. Here, we explore the roles of the bacterial type VI secretion system (T6SS), present in ~25% of gram-negative bacteria, including many symbionts, in the establishment and perturbation of bacterial commensalism, and symbiosis in host mucosal sites. This versatile apparatus drives bacterial competition, although in some cases can also interfere directly with host cells and facilitate nutrient acquisition. In addition, some bacterial pathogens cause disease when their T6SS leads to dysbiosis and subverts host immune responses in defined animal models. This review explores our knowledge of the T6SS in the context of the "host-microbiota-pathogen" triumvirate and examines contexts in which the importance of this secretion system may be underappreciated.},
}
@article {pmid33194828,
year = {2020},
author = {Arora, G and Chaudhary, D and Kidwai, S and Sharma, D and Singh, R},
title = {Corrigendum: CitE Enzymes Are Essential for Mycobacterium tuberculosis to Establish Infection in Macrophages and Guinea Pigs.},
journal = {Frontiers in cellular and infection microbiology},
volume = {10},
number = {},
pages = {587907},
doi = {10.3389/fcimb.2020.587907},
pmid = {33194828},
issn = {2235-2988},
abstract = {[This corrects the article DOI: 10.3389/fcimb.2018.00385.].},
}
@article {pmid33194431,
year = {2020},
author = {Qu, YF and Wu, YQ and Zhao, YT and Lin, LH and Du, Y and Li, P and Li, H and Ji, X},
title = {The invasive red-eared slider turtle is more successful than the native Chinese three-keeled pond turtle: evidence from the gut microbiota.},
journal = {PeerJ},
volume = {8},
number = {},
pages = {e10271},
pmid = {33194431},
issn = {2167-8359},
abstract = {Background: The mutualistic symbiosis between the gut microbial communities (microbiota) and their host animals has attracted much attention. Many factors potentially affect the gut microbiota, which also varies among host animals. The native Chinese three-keeled pond turtle (Chinemys reevesii) and the invasive red-eared slider turtle (Trachemys scripta elegans) are two common farm-raised species in China, with the latter generally considered a more successful species. However, supporting evidence from the gut microbiota has yet to be collected.
Methods: We collected feces samples from these two turtle species raised in a farm under identical conditions, and analyzed the composition and relative abundance of the gut microbes using bacterial 16S rRNA sequencing on the Roach/454 platform.
Results: The gut microbiota was mainly composed of Bacteroidetes and Firmicutes at the phylum level, and Porphyromonadaceae, Bacteroidaceae and Lachnospiraceae at the family level in both species. The relative abundance of the microbes and gene functions in the gut microbiota differed between the two species, whereas alpha or beta diversity did not. Microbes of the families Bacteroidaceae, Clostridiaceae and Lachnospiraceae were comparatively more abundant in C. reevesii, whereas those of the families Porphyromonadaceae and Fusobacteriaceae were comparatively more abundant in T. s. elegans. In both species the gut microbiota had functional roles in enhancing metabolism, genetic information processing and environmental information processing according to the Kyoto Encyclopedia of Genes and Genomes database. The potential to gain mass is greater in T. s. elegans than in C. reevesii, as revealed by the fact that the Firmicutes/Bacteroidetes ratio was lower in the former species. The percentage of human disease-related functional genes was lower in T. s. elegans than in C. reevesii, presumably suggesting an enhanced potential to colonize new habitats in the former species.},
}
@article {pmid33194344,
year = {2020},
author = {Peng, SE and Moret, A and Chang, C and Mayfield, AB and Ren, YT and Chen, WU and Giordano, M and Chen, CS},
title = {A shift away from mutualism under food-deprived conditions in an anemone-dinoflagellate association.},
journal = {PeerJ},
volume = {8},
number = {},
pages = {e9745},
pmid = {33194344},
issn = {2167-8359},
abstract = {The mutualistic symbiosis between anthozoans and intra-gastrodermal dinoflagellates of the family Symbiodiniaceae is the functional basis of all coral reef ecosystems, with the latter providing up to 95% of their fixed photosynthate to their hosts in exchange for nutrients. However, recent studies of sponges, jellyfish, and anemones have revealed the potential for this mutualistic relationship to shift to parasitism under stressful conditions. Over a period of eight weeks, we compared the physiological conditions of both inoculated and aposymbiotic anemones (Exaiptasia pallida) that were either fed or starved. By the sixth week, both fed groups of anemones were significantly larger than their starved counterparts. Moreover, inoculated and starved anemones tended to disintegrate into "tissue balls" within eight weeks, and 25% of the samples died; in contrast, starved aposymbiotic anemones required six months to form tissue balls, and no anemones from this group died. Our results show that the dinoflagellates within inoculated anemones may have posed a fatal metabolic burden on their hosts during starvation; this may be because of the need to prioritize their own metabolism and nourishment at the expense of their hosts. Collectively, our study reveals the potential of this dynamic symbiotic association to shift away from mutualism during food-deprived conditions.},
}
@article {pmid33193996,
year = {2020},
author = {Maire, J and Chouaia, B and Zaidman-Rémy, A and Heddi, A},
title = {Endosymbiosis morphological reorganization during metamorphosis diverges in weevils.},
journal = {Communicative & integrative biology},
volume = {13},
number = {1},
pages = {184-188},
pmid = {33193996},
issn = {1942-0889},
abstract = {Virtually all animals associate with beneficial symbiotic bacteria. Whether and how these associations are modulated across a host's lifecycle is an important question in disentangling animal-bacteria interactions. We recently reported a case of complete morphological reorganization of symbiosis during metamorphosis of the cereal weevil, Sitophilus oryzae. In this model, the bacteriome, a specialized organ that houses the intracellular bacterium Sodalis pierantonius, undergoes a two-phase remodeling program synchronously driven by host and endosymbiont, resulting in a localization shift and the formation of multiple new bacteriomes. Here, we provide comparative data in a closely-related coleopteran, the red palm weevil Rhynchophorus ferrugineus, which is associated with the ancestral endosymbiont Nardonella. Using cell imaging experiments, we show that the red pal weevil bacteriome remains unchanged during metamorphosis, hence contrasting with what we reported in the cereal weevil S. oryzae. These findings highlight the complexity and divergence of host-symbiont interactions and their intertwining with host development, even in closely-related species. Abbreviations: DAPI: 4',6-diamidino-2-phenylindole; FISH: Fluorescence in situ hybridization; T3SS: Type III secretion system.},
}
@article {pmid33193716,
year = {2020},
author = {Liu, A and Ku, YS and Contador, CA and Lam, HM},
title = {The Impacts of Domestication and Agricultural Practices on Legume Nutrient Acquisition Through Symbiosis With Rhizobia and Arbuscular Mycorrhizal Fungi.},
journal = {Frontiers in genetics},
volume = {11},
number = {},
pages = {583954},
pmid = {33193716},
issn = {1664-8021},
abstract = {Legumes are unique among plants as they can obtain nitrogen through symbiosis with nitrogen-fixing rhizobia that form root nodules in the host plants. Therefore they are valuable crops for sustainable agriculture. Increasing nitrogen fixation efficiency is not only important for achieving better plant growth and yield, but it is also crucial for reducing the use of nitrogen fertilizer. Arbuscular mycorrhizal fungi (AMF) are another group of important beneficial microorganisms that form symbiotic relationships with legumes. AMF can promote host plant growth by providing mineral nutrients and improving the soil ecosystem. The trilateral legume-rhizobia-AMF symbiotic relationships also enhance plant development and tolerance against biotic and abiotic stresses. It is known that domestication and agricultural activities have led to the reduced genetic diversity of cultivated germplasms and higher sensitivity to nutrient deficiencies in crop plants, but how domestication has impacted the capability of legumes to establish beneficial associations with rhizospheric microbes (including rhizobia and fungi) is not well-studied. In this review, we will discuss the impacts of domestication and agricultural practices on the interactions between legumes and soil microbes, focusing on the effects on AMF and rhizobial symbioses and hence nutrient acquisition by host legumes. In addition, we will summarize the genes involved in legume-microbe interactions and studies that have contributed to a better understanding of legume symbiotic associations using metabolic modeling.},
}
@article {pmid33193551,
year = {2020},
author = {Cibils-Stewart, X and Powell, JR and Popay, AJ and Lattanzi, FA and Hartley, SE and Johnson, SN},
title = {Reciprocal Effects of Silicon Supply and Endophytes on Silicon Accumulation and Epichloë Colonization in Grasses.},
journal = {Frontiers in plant science},
volume = {11},
number = {},
pages = {593198},
pmid = {33193551},
issn = {1664-462X},
abstract = {Cool season grasses associate asymptomatically with foliar Epichloë endophytic fungi in a symbiosis where Epichloë spp. protects the plant from a number of biotic and abiotic stresses. Furthermore, many grass species can accumulate large quantities of silicon (Si), which also alleviates a similar range of stresses. While Epichloë endophytes may improve uptake of minerals and nutrients, their impact on Si is largely unknown. Likewise, the effect of Si availability on Epichloë colonization remains untested. To assess the bidirectional relationship, we grew tall fescue (Festuca arundinacea) and perennial ryegrass (Lolium perenne) hydroponically with or without Si. Grasses were associated with five different Epichloë endophyte strains [tall fescue: AR584 or wild type (WT); perennial ryegrass: AR37, AR1, or WT] or as Epichloë-free controls. Reciprocally beneficial effects were observed for tall fescue associations. Specifically, Epichloë presence increased Si concentration in the foliage of tall fescue by at least 31%, regardless of endophyte strain. In perennial ryegrass, an increase in foliar Si was observed only for plants associated with the AR37. Epichloë promotion of Si was (i) independent of responses in plant growth, and (ii) positively correlated with endophyte colonization, which lends support to an endophyte effect independent of their impacts on root growth. Moreover, Epichloë colonization in tall fescue increased by more than 60% in the presence of silicon; however, this was not observed in perennial ryegrass. The reciprocal benefits of Epichloë-endophytes and foliar Si accumulation reported here, especially for tall fescue, might further increase grass tolerance to stress.},
}
@article {pmid33193538,
year = {2020},
author = {Wu, Z and Huang, W and Qin, E and Liu, S and Liu, H and Grennan, AK and Liu, H and Qin, R},
title = {Comprehensive Identification and Expression Profiling of Circular RNAs During Nodule Development in Phaseolus vulgaris.},
journal = {Frontiers in plant science},
volume = {11},
number = {},
pages = {587185},
pmid = {33193538},
issn = {1664-462X},
abstract = {Symbiotic nitrogen fixation by legume nodules provides an abundant nitrogen source for plants, and understanding this process is key for developing green agriculture. Circular RNA (circRNA), a type of endogenous RNA produced by reverse splicing of mRNA precursors, plays important regulatory roles in plants at the transcriptional and post-transcriptional levels. However, the relationship between circRNAs and legume-rhizobium is unknown. Here, we performed comprehensive identification and expression profiling of circRNAs during nodulation in common bean (Phaseolus vulgaris) compared to uninoculated roots of corresponding ages by constructing circRNA-seq and mRNA-seq libraries. We identified 8,842 high-confident circRNAs, 3,448 of which were specifically produced during symbiosis, with the highest number at the nitrogen-fixing stage. Significantly, more circRNAs were derived from exons than from intergenic regions or introns in all samples. The lengths and GC contents of the circRNAs were similar in roots and nodules. However, circRNAs showed specific spatiotemporal expression patterns during nodule and root development. GO and other functional annotation of parental genes of differentially expressed circRNAs indicated their potential involvement in different biological processes. The expression of major circRNAs during symbiosis is independent of parental genes' expression to a certain degree, while expression of the remaining minor circRNAs showed positive correlation to parental genes. Functional annotation of the targeted mRNAs in the circRNA-miRNA-mRNA network showed that circRNAs may be involved in transmembrane transport and positive regulation of kinase activity during nodulation and nitrogen fixation as miRNA sponges. Our comprehensive analysis of the expression profile of circRNAs and their potential functions suggests that circRNAs may function as new post-transcriptional regulators in legume-rhizobium symbiosis.},
}
@article {pmid33193249,
year = {2020},
author = {Hirota, B and Meng, XY and Fukatsu, T},
title = {Bacteriome-Associated Endosymbiotic Bacteria of Nosodendron Tree Sap Beetles (Coleoptera: Nosodendridae).},
journal = {Frontiers in microbiology},
volume = {11},
number = {},
pages = {588841},
pmid = {33193249},
issn = {1664-302X},
abstract = {The family Nosodendridae is a small group of tree sap beetles with only 91 described species representing three genera from the world. In 1930s, bacteria-harboring symbiotic organs, called bacteriomes, were briefly described in a European species Nosodendron fasciculare. Since then, however, no studies have been conducted on the nosodendrid endosymbiosis for decades. Here we investigated the bacteriomes and the endosymbiotic bacteria of Nosodendron coenosum and Nosodendron asiaticum using molecular phylogenetic and histological approaches. In adults and larvae, a pair of slender bacteriomes were found along both sides of the midgut. The bacteriomes consisted of large bacteriocytes at the center and flat sheath cells on the surface. Fluorescence in situ hybridization detected preferential localization of the endosymbiotic bacteria in the cytoplasm of the bacteriocytes. In reproductive adult females, the endosymbiotic bacteria were also detected at the infection zone in the ovarioles and on the surface of growing oocytes, indicating vertical symbiont transmission via ovarial passage. Transmission electron microscopy unveiled bizarre structural features of the bacteriocytes, whose cytoplasm exhibited degenerate cytology with deformed endosymbiont cells. Molecular phylogenetic analysis revealed that the nosodendrid endosymbionts formed a distinct clade in the Bacteroidetes. The nosodendrid endosymbionts were the most closely related to the bacteriome endosymbionts of bostrichid powderpost beetles and also allied to the bacteriome endosymbionts of silvanid grain beetles, uncovering an unexpected endosymbiont relationship across the unrelated beetle families Nosodendridae, Bostrichidae and Silvanidae. Host-symbiont co-evolution and presumable biological roles of the endosymbiotic bacteria are discussed.},
}
@article {pmid33193213,
year = {2020},
author = {Compton, KK and Hildreth, SB and Helm, RF and Scharf, BE},
title = {An Updated Perspective on Sinorhizobium meliloti Chemotaxis to Alfalfa Flavonoids.},
journal = {Frontiers in microbiology},
volume = {11},
number = {},
pages = {581482},
pmid = {33193213},
issn = {1664-302X},
abstract = {The symbiotic interaction between leguminous plants and their cognate rhizobia allows for the fixation of gaseous dinitrogen into bioavailable ammonia. The perception of host-derived flavonoids is a key initial step for the signaling events that must occur preceding the formation of the nitrogen-fixing organ. Past work investigating chemotaxis - the directed movement of bacteria through chemical gradients - of Bradyrhizobium japonicum, Rhizobium leguminosarum, and Rhizobium meliloti discovered chemotaxis to various organic compounds, but focused on chemotaxis to flavonoids because of their relevance to the symbiosis biochemistry. The current work sought to replicate and further examine Sinorhizobium (Ensifer) meliloti chemotaxis to the flavonoids previously thought to act as the principal attractant molecules prior to the initial signaling stage. Exudate from germinating alfalfa seedlings was analyzed for composition and quantities of different flavonoid compounds using mass spectrometry. The abundance of four prevalent flavonoids in germinating alfalfa seed exudates (SEs) was at a ratio of 200:5:5:1 for hyperoside, luteolin, luteolin-7-glucoside, and chrysoeriol. Using quantitative chemotaxis capillary assays, we did not detect chemotaxis of motile S. meliloti cells to these, and two other flavonoids identified in seed exudates. In support of these findings, the flavonoid fraction of seed exudates was found to be an insignificant attractant relative to the more hydrophilic fraction. Additionally, we observed that cosolvents commonly used to dissolve flavonoids confound the results. We propose that the role flavonoids play in S. meliloti chemotaxis is insignificant relative to other components released by alfalfa seeds.},
}
@article {pmid33191496,
year = {2020},
author = {Maruyama, S and Weis, VM},
title = {Limitations of Using Cultured Algae to Study Cnidarian-Algal Symbioses and Suggestions for Future Studies1.},
journal = {Journal of phycology},
volume = {},
number = {},
pages = {},
doi = {10.1111/jpy.13102},
pmid = {33191496},
issn = {1529-8817},
support = {1645164//Division of Integrative Organismal Systems/ ; },
abstract = {Much of our understanding of the cellular mechanisms underlying cnidarian-algal symbiosis comes from studying the biological differences between the partners when they are engaged in symbiosis and when they are isolated from one another. When comparing the in hospite and ex hospite states in Symbiodiniaceae, the in hospite state is represented by algae sampled from hosts, and the ex hospite state is commonly represented by cultured algae. The use of cultured algae in this comparison may introduce nutrition as a confounding variable because, while hosts are kept in nutrient-depleted conditions, culture media is nutrient rich and designed to facilitate algal growth. In this perspective, we reexamine how nutrition may be a confounding variable in studies that compare the biology of Symbiodiniaceae in hospite and in culture. We also suggest several innovations in experimental design to strengthen the comparison of the two lifestyles, including the adoption of nutritional controls, alternatives to culture for the representation of Symbiodiniaceae ex hospite, and the adoption of several proteomic approaches to find novel Symbiodiniaceae genes important for symbiosis.},
}
@article {pmid33190974,
year = {2020},
author = {Singh, P and Itankar, N and Patil, Y},
title = {Biomanagement of hexavalent chromium: Current trends and promising perspectives.},
journal = {Journal of environmental management},
volume = {},
number = {},
pages = {111547},
doi = {10.1016/j.jenvman.2020.111547},
pmid = {33190974},
issn = {1095-8630},
abstract = {Chromium (Cr) is most widely used heavy metal with vast applications in industrial sectors such as metallurgy, automobile, leather, electroplating, etc. Subsequently, these industries discharge large volumes of toxic Cr containing industrial wastewaters without proper treatment/management into the environment, causing severe damage to human health and ecology. This review gives some novel insights on the existing, successful and promising bio-based approaches for Cr remediation. In lieu of the multiple limitations of the physical and chemical methods for remediation, various biological means have been deciphered, wherein dead and live biomass have shown immense capabilities of removing/reducing and/or remediating Cr from polluted environmental niches. Adsorption of Cr by various agro-based waste and reduction/precipitation by different microbial groups have shown promising results in chromium removal/recovery. Various microbial based agents and aquatic plants like duckweeds are emerging as efficient adsorbents of metals and their role in chromium bioremediation is an effective green technology that needs to be harnessed effectively. The role of iron and sulphur reducing bacteria have shown potential for enhanced Cr remediation. Biosurfactants have revealed immense scope as enhancers of microbial metal bioremediation and have been reported to have potential for use in chromium recovery as well. The authors also explore the combined use of biochar and biosurfactants as a potential strategy for chromium bioremediation for the development of technology worth adopting. Cr is non-renewable and finite resource, therefore its safe removal/recovery from wastes is of major significance for achieving social, economic and environmental sustainability.},
}
@article {pmid33189975,
year = {2021},
author = {Mohamed, AYA and Welles, L and Siggins, A and Healy, MG and Brdjanovic, D and Rada-Ariza, AM and Lopez-Vazquez, CM},
title = {Effects of substrate stress and light intensity on enhanced biological phosphorus removal in a photo-activated sludge system.},
journal = {Water research},
volume = {189},
number = {},
pages = {116606},
doi = {10.1016/j.watres.2020.116606},
pmid = {33189975},
issn = {1879-2448},
abstract = {Photo-activated sludge (PAS) systems are an emerging wastewater treatment technology where microalgae provide oxygen to bacteria without the need for external aeration. There is limited knowledge on the optimal conditions for enhanced biological phosphorus removal (EBPR) in systems containing a mixture of polyphosphate accumulating organisms (PAOs) and microalgae. This research aimed to study the effects of substrate composition and light intensity on the performance of a laboratory-scale EBPR-PAS system. Initially, a model-based design was developed to study the effect of organic carbon (COD), inorganic carbon (HCO3) and ammonium-nitrogen (NH4-N) in nitrification deprived conditions on phosphorus (P) removal. Based on the mathematical model, two different synthetic wastewater compositions (COD:HCO3:NH4-N: 10:20:1 and 10:10:4) were examined at a light intensity of 350 µmol m-2 sec-1. Add to this, the performance of the system was also investigated at light intensities: 87.5, 175, and 262.5 µmol m-2 sec-1 for short terms. Results showed that wastewater having a high level of HCO3 and low level of NH4-N (ratio of 10:20:1) favored only microalgal growth, and had poor P removal due to a shortage of NH4-N for PAOs growth. However, lowering the HCO3 level and increasing the NH4-N level (ratio of 10:10:4) balanced PAOs and microalgae symbiosis, and had a positive influence on P removal. Under this mode of operation, the system was able to operate without external aeration and achieved a net P removal of 10.33 ±1.45 mg L-1 at an influent COD of 100 mg L-1. No significant variation was observed in the reactor performance for different light intensities, indicating the EBPR-PAS system can be operated at low light intensities with a positive influence on P removal.},
}
@article {pmid33189450,
year = {2020},
author = {Wang, G and Wang, L and Ma, F and Yang, D and You, Y},
title = {Earthworm and arbuscular mycorrhiza interactions: Strategies to motivate antioxidant responses and improve soil functionality.},
journal = {Environmental pollution (Barking, Essex : 1987)},
volume = {},
number = {},
pages = {115980},
doi = {10.1016/j.envpol.2020.115980},
pmid = {33189450},
issn = {1873-6424},
abstract = {Earthworms and arbuscular mycorrhizal fungi (AMF) act synergistically in the rhizosphere and may increase host plant tolerance to Cd. However, mechanisms by which earthworm-AMF-plant partnerships counteract Cd phytotoxicity are unknown. Thus, we evaluated individual and interactive effects of these soil organisms on photosynthesis, antioxidant capacity, and essential nutrient uptake by Solanum nigrum, as well as on soil quality following Cd exposure (0-120 mg kg-1). Decreases in biomass and photosynthetic activity, as well as nutrient imbalances were observed in Cd-stressed plants; however, the addition of AMF and earthworms reversed these effects. Cd exposure increased superoxide dismutase (SOD), peroxidase (POD), and catalase (CAT) activities, whereas inoculation with Rhizophagus intraradices decreased those. Soil enzymatic activity decreased by 15-60% with increasing Cd concentrations. However, Cd-mediated toxicity was partially reversed by soil organisms. Earthworms and AMF ameliorated soil quality based on soil enzyme activity. At 120 mg kg-1 Cd, the urease, catalase, and acid phosphatase activities were 1.6-, 1.4-, and 1.2-fold higher, respectively, in soils co-incubated with earthworms and AMF than in uninoculated soil. Cd inhibited shoot Fe and Ca phytoaccumulation, whereas AMF and earthworms normalized the status of essential elements in plants. Cd detoxification by earthworm-AMF-S. nigrum symbiosis was manifested by increases in plant biomass accumulation (22-117%), chlorophyll content (17-63%), antioxidant levels (SOD 10-18%, POD 9-25%, total polyphenols 17-22%, flavonoids 15-29%, and glutathione 7-61%). It also ameliorated the photosynthetic capacity, and macro- and micronutrient statuses of plants; markedly reduced the levels of malondialdehyde (20-27%), superoxide anion (29-36%), and hydrogen peroxide (19-30%); and upregulated the transcription level of FeSOD. Thus, the combined action of earthworms and AMF feasibly enhances metal tolerance of hyperaccumulating plants and improves the quality of polluted soil.},
}
@article {pmid33188641,
year = {2020},
author = {Ma, X and Geng, Q and Zhang, H and Bian, C and Chen, HYH and Jiang, D and Xu, X},
title = {Global negative effects of nutrient enrichment on arbuscular mycorrhizal fungi, plant diversity and ecosystem multifunctionality.},
journal = {The New phytologist},
volume = {},
number = {},
pages = {},
doi = {10.1111/nph.17077},
pmid = {33188641},
issn = {1469-8137},
support = {//"5151" Talent Program of Nanjing Forestry University/ ; KYCX19_1095//Postgraduate Research & Practice Innovation Program of Jiangsu Province/ ; 17KJA180006//Natural Science Key Fund for Colleges and Universities of Jiangsu Province of China/ ; //Priority Academic Program Development of Jiangsu Higher Education Institutions (PAPD)/ ; JY-041& TD-XYDXX-006//Six Talent Peaks Program of Jiangsu Province/ ; 31700376//National Science Foundation/ ; },
abstract = {Despite widespread anthropogenic nutrient enrichment, it remains unclear how nutrient enrichment influences plant-arbuscular mycorrhizal fungi (AMF) symbiosis and ecosystem multifunctionality at the global scale. Here, we conducted a meta-analysis to examine the worldwide effects of nutrient enrichment on AMF and plant diversity and ecosystem multifunctionality using data of field experiments from 136 papers. Our analyses showed that nutrient addition simultaneously decreased AMF diversity and abundance belowground and plant diversity aboveground at the global scale. The decreases in AMF diversity and abundance associated with nutrient addition were more pronounced with increasing experimental duration, mean annual temperature (MAT) and mean annual precipitation (MAP). Nutrient addition-induced changes in soil pH and available phosphorus (P) predominantly regulated the responses of AMF diversity and abundance. Furthermore, AMF diversity correlated with ecosystem multifunctionality under nutrient addition worldwide. Our findings identify the negative effects of nutrient enrichment on AMF and plant diversity and suggest that AMF diversity is closely linked with ecosystem function. This study offers an important advancement in our understanding of plant-AMF interactions and their likely responses to ongoing global change.},
}
@article {pmid33187223,
year = {2020},
author = {Shelomi, M and Chen, MJ},
title = {Culturing-Enriched Metabarcoding Analysis of the Oryctes rhinoceros Gut Microbiome.},
journal = {Insects},
volume = {11},
number = {11},
pages = {},
pmid = {33187223},
issn = {2075-4450},
support = {106-2311-B-002-002-MY3//Ministry of Science and Technology, Taiwan/ ; },
abstract = {Wood-feeding insects should have a source of enzymes like cellulases to digest their food. These enzymes can be produced by the insect, or by microbes living in the wood and/or inside the insect gut. The coconut rhinoceros beetle, Oryctes rhinoceros, is a pest whose digestive microbes are of considerable interest. This study describes the compartments of the O. rhinoceros gut and compares their microbiomes using culturing-enriched metabarcoding. Beetle larvae were collected from a coconut grove in southern Taiwan. Gut contents from the midgut and hindgut were plated on nutrient agar and selective carboxymethylcellulose agar plates. DNA was extracted from gut and fat body samples and 16S rDNA metabarcoding performed to identify unculturable bacteria. Cellulase activity tests were performed on gut fluids and microbe isolates. The midgut and hindgut both showed cellulolytic activity. Bacillus cereus, Citrobacter koseri, and the cellulolytic fungus Candida xylanilytica were cultured from both gut sections in most larvae. Metabarcoding did not find Bacillus cereus, and found that either Citrobacter koseri or Paracoccus sp. were the dominant gut microbes in any given larva. No significant differences were found between midgut and hindgut microbiomes. Bacillus cereus and Citrobacter koseri are common animal gut microbes frequently found in Oryctes rhinoceros studies while Candida xylanilytica and the uncultured Paracoccus sp. had not been identified in this insect before. Some or all of these may well have digestive functions for the beetle, and are most likely acquired from the diet, meaning they may be transient commensalists rather than obligate mutualists. Broader collection efforts and tests with antibiotics will resolve ambiguities in the beetle-microbe interactions.},
}
@article {pmid33185681,
year = {2020},
author = {Yoshioka, Y and Yamashita, H and Suzuki, G and Zayasu, Y and Tada, I and Kanda, M and Satoh, N and Shoguchi, E and Shinzato, C},
title = {Whole-genome transcriptome analyses of native symbionts reveal host coral genomic novelties for establishing coral-algae symbioses.},
journal = {Genome biology and evolution},
volume = {},
number = {},
pages = {},
doi = {10.1093/gbe/evaa240},
pmid = {33185681},
issn = {1759-6653},
abstract = {Reef-building corals and photosynthetic, endosymbiotic algae of the family Symbiodiniaceae establish mutualistic relationships that are fundamental to coral biology, enabling coral reefs to support a vast diversity of marine species. Although numerous types of Symbiodiniaceae occur in coral reef environments, Acropora corals select specific types in early life stages. In order to study molecular mechanisms of coral-algal symbioses occurring in nature, we performed whole-genome transcriptomic analyses of Acropora tenuis larvae inoculated with Symbiodinium microadriaticum strains isolated from Acropora. In order to identify genes specifically involved in symbioses with native symbionts in early life stages, we also investigated transcriptomic responses of Acropora larvae exposed to closely related, non-symbiotic, and occasionally symbiotic Symbiodinium strains. We found that the number of differentially expressed genes was largest when larvae acquired native symbionts. Repertoires of differentially expressed genes indicated that corals reduced amino acid, sugar, and lipid metabolism, such that metabolic enzymes performing these functions were derived primarily from S. microadriaticum rather than from A. tenuis. Up-regulated gene expression of transporters for those metabolites occurred only when coral larvae acquired their natural symbionts, suggesting active utilization of native symbionts by host corals. We also discovered that in Acropora, genes for sugar and amino acid transporters, prosaposin-like, and Notch ligand-like, were up-regulated only in response to native symbionts, and included tandemly duplicated genes. Gene duplications in coral genomes may have been essential to establish genomic novelties for coral-algae symbiosis.},
}
@article {pmid33185350,
year = {2020},
author = {Bukharin, OV and Kuzmin, MD and Perunova, NB and Ivanova, EV and Bekpergenova, AV and Bondarenko, TA},
title = {[Characterization of the microbiota and cytokine profile of sperm plasma in men with chronic bacterial prostatitis].},
journal = {Urologiia (Moscow, Russia : 1999)},
volume = {},
number = {5},
pages = {67-72},
pmid = {33185350},
issn = {1728-2985},
mesh = {Cytokines ; Humans ; *Infertility, Male ; Male ; *Microbiota ; *Prostatitis ; Semen ; Sperm Count ; Sperm Motility ; Spermatozoa ; },
abstract = {BACKGROUND: One of the leading causes of the occurrence of chronic bacterial prostatitis (CBP) in men is infection, microecological disorders of the urogenital tract and cytokine-mediated mechanisms of inflammation of the prostate gland, which actualizes a comprehensive study of the clinical and bacteriological features of CBP from the perspective of a symbiotic approach in the framework of a new scientific field - "infectious symbiology".
OBJECTIVE: to study the characteristics of spermogram, microbiota, and the cytokine profile in men with chronic bacterial prostatitis (CBP) and CBP complicated by infertility.
MATERIALS AND METHODS: A comprehensive study of patients with CBP and CBP complicated by infertility, in comparison with conditionally healthy individuals, was conducted. Species identification of microorganisms was carried out according to biochemical characteristics and the genetic method (sequencing of strains). The biological properties of the microbiota were evaluated: growth properties, biofilm formation, antipeptide activity against the cytokines IL-10, RAIL-1, TNF-, INF- and IL-17 (8 parameters). Immunological parameters of sperm plasma included 13 parameters: the content of cytokines TNF-, INF-, Rail, interleukins (IL) -1, 2, 4, 6, 8, 10, 17, immunoglobulin (Ig) A, lactoferrin and lysozyme. To evaluate sperm plasma, the following quantities were determined: ejaculate volume, pH, sperm plasma liquefaction, total sperm count, sperm count per 1 ml, motility, number of progressively motile, non-progressive motile and motionless spermatozoa, number of round cells, white blood cells, spermatogenesis cells, erythrocytes, erythrocytes, cells, sperm agglutination and aggregation (16 parameters in total). The results are statistically processed.
RESULTS: Data were obtained on changes in biofilm formation, antipeptide activity of microbiota (especially pronounced in corynebacteria), sperm plasma cytokine profile (increased TNF , IL-2, 6, 17), as well as IgA and lactoferrin, which can be used to build a prognostic model of reproductive pathology tract of men and their fertile activity.
CONCLUSION: The study of the antipeptide activity of microbiota in combination with the cytokine profile of ejaculate allows us to recommend them as a "biotarget" for diagnostic, preventive and therapeutic measures for chronic prostatitis in men, which contribute to solving the medical and social problem of preventing male infertility and contributes to the development of health-saving technologies with incorporating elements of personalized medicine.},
}
@article {pmid33184570,
year = {2020},
author = {Braunberger, P},
title = {Symbiosis and survival: Xanthoria elegans.},
journal = {Journal of the Canadian Academy of Child and Adolescent Psychiatry = Journal de l'Academie canadienne de psychiatrie de l'enfant et de l'adolescent},
volume = {29},
number = {4},
pages = {256-259},
pmid = {33184570},
issn = {1719-8429},
}
@article {pmid33184348,
year = {2020},
author = {Huffines, JT and Scoffield, JA},
title = {Disruption of Streptococcus mutans and Candida albicans synergy by a commensal streptococcus.},
journal = {Scientific reports},
volume = {10},
number = {1},
pages = {19661},
pmid = {33184348},
issn = {2045-2322},
support = {R00 DE025913/DE/NIDCR NIH HHS/United States ; },
mesh = {Biofilms ; Candida albicans/*metabolism ; Glucans/metabolism ; Glucosyltransferases/metabolism ; Hydrogen Peroxide/metabolism ; Metabolomics ; Streptococcus/*metabolism ; Streptococcus mutans/*metabolism ; Sucrose ; Symbiosis ; },
abstract = {Polymicrobial interactions in dental plaque play a significant role in dysbiosis and homeostasis in the oral cavity. In early childhood caries, Streptococcus mutans and Candida albicans are often co-isolated from carious lesions and associated with increased disease severity. Studies have demonstrated that metabolic and glucan-dependent synergism between C. albicans and S. mutans contribute to enhanced pathogenesis. However, it is unclear how oral commensals influence pathogen synergy. Streptococcus parasanguinis, a hydrogen peroxide (H2O2) producing oral commensal, has antimicrobial activity against S. mutans. In this study, we utilized a three species biofilm model to understand the impact of S. parasanguinis on S. mutans and C. albicans synergy. We report that S. parasanguinis disrupts S. mutans and C. albicans biofilm synergy in a contact and H2O2-independent manner. Further, metabolomics analysis revealed a S. parasanguinis-driven alteration in sugar metabolism that restricts biofilm development by S. mutans. Moreover, S. parasanguinis inhibits S. mutans glucosyltransferase (GtfB) activity, which is important for glucan matrix development and GtfB-mediated binding to C. albicans mannan. Taken together, our study describes a new antimicrobial role for S. parasanguinis and highlights how this abundant oral commensal may be utilized to attenuate pathogen synergism.},
}
@article {pmid33184315,
year = {2020},
author = {Kagawa, O and Uchida, S and Yamazaki, D and Osawa, Y and Ito, S and Chiba, S and , },
title = {Citizen science via social media revealed conditions of symbiosis between a marine gastropod and an epibiotic alga.},
journal = {Scientific reports},
volume = {10},
number = {1},
pages = {19647},
pmid = {33184315},
issn = {2045-2322},
abstract = {Environmental factors promote symbiosis, but its mechanism is not yet well understood. The alga Pseudocladophora conchopheria grows only on the shell of an intertidal gastropod Lunella correensis, and these species have a close symbiotic relationship which the alga reduces heat stress of the gastropod. In collaboration with general public, we investigated how environmental conditions alter the symbiotic interaction between the alga and the gastropod. Information about the habitats of each gastropod and images of shells was obtained from the Japanese and Korean coasts via social media. We constructed the hierarchical Bayesian model using the data. The results indicated that the proportion of shell area covered by P. conchopheria increased as the substrate size utilized by the gastropod increased. Meanwhile, temperature did not affect the proportion of P. conchopheria on the shell. These suggested that the alga provides no benefits for the gastropod on small substrates because gastropod can reduce the heat stress by diving into the small sediment. Further, the gastropod's cost incurred by growing the alga on the shell seems to be low as the algae can grow even in cooler places where no benefits of heat resistance for gastropods. Different environments can yield variable conditions in symbiosis.},
}
@article {pmid33183238,
year = {2020},
author = {Yuan, S and Ke, D and Li, R and Li, X and Wang, L and Chen, H and Zhang, C and Huang, Y and Chen, L and Hao, Q and Yang, H and Cao, D and Chen, S and Guo, W and Shan, Z and Yang, Z and Zhang, X and Qiu, D and Guan, Y and Zhou, X},
title = {Genome-wide survey of soybean papain-like cysteine proteases and their expression analysis in root nodule symbiosis.},
journal = {BMC plant biology},
volume = {20},
number = {1},
pages = {517},
pmid = {33183238},
issn = {1471-2229},
abstract = {BACKGROUND: Plant papain-like cysteine proteases (PLCPs) are a large class of proteolytic enzymes and play important roles in root nodule symbiosis (RNS), while the whole-genome studies of PLCP family genes in legume are quite limited, and the roles of Glycine max PLCPs (GmPLCPs) in nodulation, nodule development and senescence are not fully understood.
RESULTS: In the present study, we identified 97 GmPLCPs and performed a genome-wide survey to explore the expansion of soybean PLCP family genes and their relationships to RNS. Nineteen paralogous pairs of genomic segments, consisting of 77 GmPLCPs, formed by whole-genome duplication (WGD) events were identified, showing a high degree of complexity in duplication. Phylogenetic analysis among different species showed that the lineage differentiation of GmPLCPs occurred after family expansion, and large tandem repeat segment were specifically in soybean. The expression patterns of GmPLCPs in symbiosis-related tissues and nodules identified RNS-related GmPLCPs and provided insights into their putative symbiotic functions in soybean. The symbiotic function analyses showed that a RNS-related GmPLCP gene (Glyma.04G190700) really participate in nodulation and nodule development.
CONCLUSIONS: Our findings improved our understanding of the functional diversity of legume PLCP family genes, and provided insights into the putative roles of the legume PLCPs in nodulation, nodule development and senescence.},
}
@article {pmid33181990,
year = {2021},
author = {Ramin, E and Bestuzheva, K and Gargalo, CL and Ramin, D and Schneider, C and Ramin, P and Flores-Alsina, X and Andersen, MM and Gernaey, KV},
title = {Incremental design of water symbiosis networks with prior knowledge: The case of an industrial park in Kenya.},
journal = {The Science of the total environment},
volume = {751},
number = {},
pages = {141706},
doi = {10.1016/j.scitotenv.2020.141706},
pmid = {33181990},
issn = {1879-1026},
abstract = {Industrial parks have a high potential for recycling and reusing resources such as water across companies by creating symbiosis networks. In this study, we introduce a mathematical optimization framework for the design of water network integration in industrial parks formulated as a large-scale standard mixed-integer non-linear programming (MINLP) problem. The novelty of our approach relies on i) developing a multi-level incremental optimization framework for water network synthesis, ii) including prior knowledge of water demand growth and projected water scarcity to evaluate the significance of water-saving solutions, iii) incorporating a comprehensive formulation of the water network synthesis problem including multiple pollutants and different treatment units and iv) performing a multi-objective optimization of the network including freshwater savings and relative cost of the network. The significance of the proposed optimization framework is illustrated by applying it to an existing industrial park in a water-scarce region in Kenya. Firstly, we illustrated the benefits of including prior knowledge to prevent an over-design of the network at the early stages. In the case study, we achieved a more flexible and expandable water network with 36% lower unit cost at the early stage and 15% lower unit cost at later stages for overall maximum freshwater savings of 25%. Secondly, multi-objective analysis suggests an optimum freshwater savings of 14% to reduce the unit cost of the network by half. Moreover, the significance of symbiosis networks is highlighted by showing that intra-company connections can only achieve a maximum freshwater savings of 17% with significantly higher unit cost (+45%). Finally, we showed that the values of symbiosis connectivity index in the Pareto front correspond to higher freshwater savings, indicating the significant role of the symbiosis network in the industrial park under study. This is the first study, where all the above elements have been taken into account simultaneously for the design of a water reuse network.},
}
@article {pmid33178254,
year = {2020},
author = {Tahayori, B},
title = {Prokaryote-Eukaryote Symbiosis to Produce RNA-Based Therapeutics.},
journal = {Frontiers in genetics},
volume = {11},
number = {},
pages = {583464},
pmid = {33178254},
issn = {1664-8021},
}
@article {pmid33178165,
year = {2020},
author = {Bengoa, AA and Dardis, C and Gagliarini, N and Garrote, GL and Abraham, AG},
title = {Exopolysaccharides From Lactobacillus paracasei Isolated From Kefir as Potential Bioactive Compounds for Microbiota Modulation.},
journal = {Frontiers in microbiology},
volume = {11},
number = {},
pages = {583254},
pmid = {33178165},
issn = {1664-302X},
abstract = {Microbiota coexists in true symbiosis with the host playing pivotal roles as a key element for well-being and health. Exopolysaccharides from lactic acid bacteria are an alternative as novel potential prebiotics that increase microbiota diversity. Considering this, the aim of the present work was to evaluate the capacity of the EPS produced by two L. paracasei strains isolated from kefir grains, to be metabolized in vitro by fecal microbiota producing short chain fatty acids. For this purpose, fecal samples from healthy children were inoculated in a basal medium with EPS and incubated in anaerobiosis at 37°C for 24, 48, and 72 h. DGGE profiles and the production of SCFA after fermentation were analyzed. Additionally, three selected samples were sequenced by mass sequencing analysis using Ion Torrent PGM. EPS produced by L. paracasei CIDCA 8339 (EPS8339) and CIDCA 83124 (EPS83124) are metabolized by fecal microbiota producing a significant increase in SCFA. EPS8339 fermentation led to an increment of propionate and butyrate, while fermentation of EPS83124 increased butyrate levels. Both EPS led to a profile of SCFA different from the ones obtained with inulin or glucose fermentation. DGGE profiles of 72 h fermentation demonstrated that both EPS showed a different band profile when compared to the controls; EPS profiles grouped in a cluster that have only 65% similarity with glucose or inulin profiles. Mass sequencing analysis demonstrated that the fermentation of EPS8339 leads to an increase in the proportion of the genera Victivallis, Acidaminococcus and Comamonas and a significant drop in the proportion of enterobacteria. In the same direction, the fermentation of EPS83124 also resulted in a marked reduction of Enterobacteriaceae with a significant increase in the genus Comamonas. It was observed that the changes in fecal microbiota and SCFA profile exerted by both polymers are different probably due to differences in their structural characteristics. It can be concluded that EPS synthesized by both L. paracasei strains, could be potentially used as bioactive compound that modify the microbiota increasing the production of propionic and butyric acid, two metabolites highly associated with beneficial effects both at the gastrointestinal and extra-intestinal level.},
}
@article {pmid33177277,
year = {2020},
author = {Goto, S and Ohbayashi, T and Takeshita, K and Sone, T and Matsuura, Y and Mergaert, P and Kikuchi, Y},
title = {A Peptidoglycan Amidase Mutant of Burkholderia insecticola Adapts an L-form-like Shape in the Gut Symbiotic Organ of the Bean Bug Riptortus pedestris.},
journal = {Microbes and environments},
volume = {35},
number = {4},
pages = {},
pmid = {33177277},
issn = {1347-4405},
abstract = {Bacterial cell shapes may be altered by the cell cycle, nutrient availability, environmental stress, and interactions with other organisms. The bean bug Riptortus pedestris possesses a symbiotic bacterium, Burkholderia insecticola, in its midgut crypts. This symbiont is a typical rod-shaped bacterium under in vitro culture conditions, but changes to a spherical shape inside the gut symbiotic organ of the host insect, suggesting the induction of morphological alterations in B. insecticola by host factors. The present study revealed that a deletion mutant of a peptidoglycan amidase gene (amiC), showing a filamentous chain form in vitro, adapted a swollen L-form-like cell shape in midgut crypts. Spatiotemporal observations of the ΔamiC mutant in midgut crypts revealed the induction of swollen cells, particularly prior to the molting of insects. To elucidate the mechanisms underlying in vivo-specific morphological alterations, the symbiont was cultured under 13 different conditions and its cell shape was examined. Swollen cells, similar to symbiont cells in midgut crypts, were induced when the mutant was treated with fosfomycin, an inhibitor of peptidoglycan precursor biosynthesis. Collectively, these results strongly suggest that the Burkholderia symbiont in midgut crypts is under the control of the host insect via a cell wall-attacking agent.},
}
@article {pmid33177190,
year = {2020},
author = {Masson, F and Lemaitre, B},
title = {Growing Ungrowable Bacteria: Overview and Perspectives on Insect Symbiont Culturability.},
journal = {Microbiology and molecular biology reviews : MMBR},
volume = {84},
number = {4},
pages = {},
pmid = {33177190},
issn = {1098-5557},
abstract = {Insects are often involved in endosymbiosis, that is, the housing of symbiotic microbes within their tissues or within their cells. Endosymbionts are a major driving force in insects' evolution, because they dramatically affect their host physiology and allow them to adapt to new niches, for example, by complementing their diet or by protecting them against pathogens. Endosymbiotic bacteria are, however, fastidious and therefore difficult to manipulate outside of their hosts, especially intracellular species. The coevolution between hosts and endosymbionts leads to alterations in the genomes of endosymbionts, limiting their ability to cope with changing environments. Consequently, few insect endosymbionts are culturable in vitro and genetically tractable, making functional genetics studies impracticable on most endosymbiotic bacteria. However, recently, major progress has been made in manipulating several intracellular endosymbiont species in vitro, leading to astonishing discoveries on their physiology and the way they interact with their host. This review establishes a comprehensive picture of the in vitro tractability of insect endosymbiotic bacteria and addresses the reason why most species are not culturable. By compiling and discussing the latest developments in the design of custom media and genetic manipulation protocols, it aims at providing new leads to expand the range of tractable endosymbionts and foster genetic research on these models.},
}
@article {pmid33175396,
year = {2020},
author = {Prasad, S and Rajan, A and Pasha, SA and Mangalore, S and Saini, J and Ingalhalikar, M and Pal, PK},
title = {Abnormal structural connectivity in progressive supranuclear palsy-Richardson syndrome.},
journal = {Acta neurologica Scandinavica},
volume = {},
number = {},
pages = {},
doi = {10.1111/ane.13372},
pmid = {33175396},
issn = {1600-0404},
support = {ECR/2016/000808//Science and Engineering Research Board/ ; },
abstract = {OBJECTIVES: Progressive supranuclear palsy-Richardson syndrome (PSP-RS) is characterized by symmetrical parkinsonism with postural instability and frontal dysfunction. This study aims to use the whole brain structural connectome (SC) to gain insights into the underlying disconnectivity which may be implicated in the clinical features of PSP-RS.
METHODS: Sixteen patients of PSP-RS and 12 healthy controls were recruited. Disease severity was quantified using PSP rating scale (PSPRS), and mini-mental scale was applied to evaluate cognition. Thirty-two direction diffusion MRIs were acquired and used to compute the structural connectome of the whole brain using deterministic fiber tracking. Group analyses were performed at the edge-wise, nodal, and global levels. Age and gender were used as nuisance covariates for all the subsequent analyses, and FDR correction was applied.
RESULTS: Network-based statistics revealed a 34-edge network with significantly abnormal edge-wise connectivity in the patient group. Of these, 25 edges were cortical connections, of which 68% were frontal connections. Abnormal deep gray matter connections were predominantly comprised of connections between structures of the basal ganglia. The characteristic path length of the SC was lower in PSP-RS, and nodal analysis revealed abnormal degree, strength, local efficiency, betweenness centrality, and participation coefficient in several nodes.
CONCLUSIONS: Significant alterations in the structural connectivity of the whole brain connectome were observed in PSP-RS. The higher degree of abnormality observed in nodes belonging to the frontal lobe and basal ganglia substantiates the predominant frontal dysfunction and parkinsonism observed in PSP-RS. The findings of this study support the concept that PSP-RS may be a network-based disorder.},
}
@article {pmid33174770,
year = {2020},
author = {Avadhanam, V and Ingavle, G and Zheng, Y and Kumar, S and Liu, C and Sandeman, S},
title = {Biomimetic bone-like composites as osteo-odonto-keratoprosthesis skirt substitutes.},
journal = {Journal of biomaterials applications},
volume = {},
number = {},
pages = {885328220972219},
doi = {10.1177/0885328220972219},
pmid = {33174770},
issn = {1530-8022},
abstract = {Osteo-odonto-keratoprostheses, incorporating dental laminate material as an anchoring skirt around a central poly(methyl methacrylate) (PMMA) optic, have been used to replace the cornea for many years. However, there are many intricacies associated with the use of autologous dental laminate material, surgical complexity and skirt erosion. Tissue engineering approaches to bone replacement may offer suitable alternatives in osteo-odonto-keratoprosthesis (OOKP) surgery. In this study, a hydrogel polymer composite was investigated as a synthetic substitute for the OOKP skirt. A novel high strength interpenetrating network (IPN) hydrogel composite with nano-crystalline hydroxyapatite (nHAp) coated poly (lactic-co-glycolic acid) PLGA microspheres was created to mimic the alveo-dental lamina by employing agarose and poly(ethylene glycol) diacrylate (PEGDA) polymers. The incorporation of nHAp coated PLGA microspheres into the hybrid IPN network provide a micro-environment similar to that of skeletal tissues and improve cellular response. Agarose was used as a first network to encapsulate keratocytes/3T3 fibroblasts and PEGDA (6000 Da) was used as a second network with varying concentrations (20 and 40 wt %) to produce a strong and biocompatible scaffold. An increased concentration of either agarose or PEG-DA and incorporation of nHAp coated PLGA microspheres led to an increase in the elastic modulus. The IPN hydrogel combinations supported the adhesion and proliferation of both fibroblast and ocular human keratocyte cell types during in in-vitro testing. The cells endured the encapsulation process into the IPN and remained viable at 1 week post-encapsulation in the presence of nHAp coated microspheres. The material did not induce significant production of inflammatory cytokine IL-6 in comparison to a positive control (p < 0.05) indicating non-inflammatory potential. The nHAp encapsulated composite IPN hydrogels are mechanically strong, cell supportive, non-inflammatory materials supporting their development as OOKP skirt substitutes using a new approach to dental laminate biomimicry in the OOKP skirt material.},
}
@article {pmid33172703,
year = {2020},
author = {Izadi, P and Izadi, P and Eldyasti, A},
title = {Towards mainstream deammonification: Comprehensive review on potential mainstream applications and developed sidestream technologies.},
journal = {Journal of environmental management},
volume = {},
number = {},
pages = {111615},
doi = {10.1016/j.jenvman.2020.111615},
pmid = {33172703},
issn = {1095-8630},
abstract = {Deammonification (partial nitritation-anammox) process is a favorable and innovative process, for treatment of nitrogen-rich wastewater due to decreased oxygen and carbon requirements at very high nitrogen loadings. The bacterial groups responsible for this process are anaerobic ammonium oxidation (anammox) bacteria in symbiosis with ammonium oxidizing bacteria (AOB) which have an active role in development of nitrogen removal biotechnology in wastewater. Development and operation of sidestream deammonification processes has augmented since the initial full-scale systems, yet there are several aspects which mandate additional investigation and deliberation by the practitioners, to reach the operating perspective, set for the facility. Process technologies for treatment of streams with high ammonia concentrations continue to emerge, correspondingly, further investigation towards feasibility of applying the deammonification concept, in the mainstream treatment process is required. Mainstream deammonification can potentially improve the process of achieving more sustainable and energy-neutral municipal wastewater treatment, however feasible applications are not accessible yet. This critical review focuses on a comprehensive assessment of the worldwide lab-scale, pilot-scale and full-scale sidestream applications as well as identifying the major issues obstructing the implementation of mainstream processes, in addition to the designs, operational factors and technology advancements at both novel and/or conventional levels. This review aims to provide a novel and broad overview of the status and challenges of both sidestream and mainstream deammonification technologies and installations worldwide to assess the global perspectives on deammonification research in the recent years. The different configurations, crucial factors and overall trends in the development of deammonification research are discussed and conclusively, the future needs for feasible applications are critically reviewed.},
}
@article {pmid33171105,
year = {2020},
author = {Saha, S and Basak, B and Hwang, JH and Salama, ES and Chatterjee, PK and Jeon, BH},
title = {Microbial Symbiosis: A Network towards Biomethanation.},
journal = {Trends in microbiology},
volume = {28},
number = {12},
pages = {968-984},
doi = {10.1016/j.tim.2020.03.012},
pmid = {33171105},
issn = {1878-4380},
abstract = {Biomethanation through anaerobic digestion (AD) is the most reliable energy harvesting process to achieve waste-to-energy. Microbial communities, including hydrolytic and fermentative bacteria, syntrophic bacteria, and methanogenic archaea, and their interspecies symbioses allow complex metabolisms for the volumetric reduction of organic waste in AD. However, heterogeneity in organic waste induces community shifts in conventional anaerobic digesters treating sewage sludge at wastewater treatment plants globally. Assessing the metabolic roles of individual microbial species in syntrophic communities remains a challenge, but such information has important implications for microbially enhanced energy recovery. This review focuses on the alterations in digester microbiome and intricate interspecies networks during substrate variation, symbiosis among the populations, and their implications for biomethanation to aid stable operation in real-scale digesters.},
}
@article {pmid33168733,
year = {2020},
author = {Cleves, PA and Krediet, CJ and Lehnert, EM and Onishi, M and Pringle, JR},
title = {Insights into coral bleaching under heat stress from analysis of gene expression in a sea anemone model system.},
journal = {Proceedings of the National Academy of Sciences of the United States of America},
volume = {117},
number = {46},
pages = {28906-28917},
pmid = {33168733},
issn = {1091-6490},
support = {P30 DK116074/DK/NIDDK NIH HHS/United States ; S10 OD025212/OD/NIH HHS/United States ; },
abstract = {Loss of endosymbiotic algae ("bleaching") under heat stress has become a major problem for reef-building corals worldwide. To identify genes that might be involved in triggering or executing bleaching, or in protecting corals from it, we used RNAseq to analyze gene-expression changes during heat stress in a coral relative, the sea anemone Aiptasia. We identified >500 genes that showed rapid and extensive up-regulation upon temperature increase. These genes fell into two clusters. In both clusters, most genes showed similar expression patterns in symbiotic and aposymbiotic anemones, suggesting that this early stress response is largely independent of the symbiosis. Cluster I was highly enriched for genes involved in innate immunity and apoptosis, and most transcript levels returned to baseline many hours before bleaching was first detected, raising doubts about their possible roles in this process. Cluster II was highly enriched for genes involved in protein folding, and most transcript levels returned more slowly to baseline, so that roles in either promoting or preventing bleaching seem plausible. Many of the genes in clusters I and II appear to be targets of the transcription factors NFκB and HSF1, respectively. We also examined the behavior of 337 genes whose much higher levels of expression in symbiotic than aposymbiotic anemones in the absence of stress suggest that they are important for the symbiosis. Unexpectedly, in many cases, these expression levels declined precipitously long before bleaching itself was evident, suggesting that loss of expression of symbiosis-supporting genes may be involved in triggering bleaching.},
}
@article {pmid33166751,
year = {2021},
author = {Sikorskaya, TV and Efimova, KV and Imbs, AB},
title = {Lipidomes of phylogenetically different symbiotic dinoflagellates of corals.},
journal = {Phytochemistry},
volume = {181},
number = {},
pages = {112579},
doi = {10.1016/j.phytochem.2020.112579},
pmid = {33166751},
issn = {1873-3700},
mesh = {Animals ; *Anthozoa ; *Dinoflagellida ; Ecosystem ; Lipidomics ; Symbiosis ; },
abstract = {The structural base of all membranes of symbiotic dinoflagellates (SD) is composed of glycolipids and betaine lipids, whereas triacylglycerols (TG) constitute an energy reserve and are involved in biosynthesis of glycolipids. Since data on the SD lipidome and the host's influence on symbionts' lipidome are scanty, we analyzed and compared the lipidomes of SD isolated from the zoantharian Palythoa tuberculosa and the alcyonarian Sinularia heterospiculata. A sequencing of nuclear gene regions showed that both cnidarians hosted the dinoflagellates Cladocopium sp. (subclades C1 and C3), but the zoantharian also contained the dinoflagellates Durusdinium trenchii (clade D). The presence of the thermotolerant D. trenchii resulted in a higher unsaturation of mono- and digalactosyldiacylglycerols (MGDG and DGDG), but a lower unsaturation of sulfoquinovosyldiacylglycerol (SQDG). The same features were earlier described for same SD from a reef-building coral. Hence, the profile of glycolipid molecules, which form SD thylakoid membranes, seems to be species-specific and does not depend on the host's taxonomic position. In contrast, the betaine lipid molecular species profile of diacylglyceryl-3-O-carboxyhydroxymethylcholine (DGCC), which forms SD cell membranes, can be influenced by the host. The profiles of the TG molecular species from freshly isolated SD have been determined for the first time. These molecular species can be divided on the basis of the acyl group in sn-2 position. The TG with 16:0 acyl group in sn-2 position may enrich total TG of a cnidarian colony and originate from SD cytoplasm. In contrast, TG 18:3/18:4/18:3 may be biosynthetically related with DGDG and concentrated in SD plastoglobules. Our data may be useful for further investigations of natural and technogenic variations in microalgal lipids and symbiont-host interactions in marine ecosystems.},
}
@article {pmid33166245,
year = {2020},
author = {Davray, D and Deo, D and Kulkarni, R},
title = {Plasmids encode niche-specific traits in Lactobacillaceae.},
journal = {Microbial genomics},
volume = {},
number = {},
pages = {},
doi = {10.1099/mgen.0.000472},
pmid = {33166245},
issn = {2057-5858},
abstract = {Species belonging to the family Lactobacillaceae are found in highly diverse environments and play an important role in fermented foods and probiotic products. Many of these species have been individually reported to harbour plasmids that encode important genes. In this study, we performed comparative genomic analysis of publicly available data for 512 plasmids from 282 strains represented by 51 species of this family and correlated the genomic features of plasmids with the ecological niches in which these species are found. Two-thirds of the species had at least one plasmid-harbouring strain. Plasmid abundance and GC content were significantly lower in vertebrate-adapted species as compared to nomadic and free-living species. Hierarchical clustering highlighted the distinct nature of plasmids from the nomadic and free-living species than those from the vertebrate-adapted species. EggNOG-assisted functional annotation revealed that genes associated with transposition, conjugation, DNA repair and recombination, exopolysaccharide production, metal ion transport, toxin-antitoxin system, and stress tolerance were significantly enriched on the plasmids of the nomadic and in some cases nomadic and free-living species. On the other hand, genes related to anaerobic metabolism, ABC transporters and the major facilitator superfamily were overrepresented on the plasmids of the vertebrate-adapted species. These genomic signatures correlate with the comparatively nutrient-depleted, stressful and dynamic environments of nomadic and free-living species and nutrient-rich and anaerobic environments of vertebrate-adapted species. Thus, these results indicate the contribution of the plasmids in the adaptation of lactobacilli to their respective habitats. This study also underlines the potential application of these plasmids in improving the technological and probiotic properties of lactic acid bacteria.},
}
@article {pmid33165962,
year = {2020},
author = {Blackstone, NW and Gutterman, JU},
title = {Can natural selection and druggable targets synergize? Of nutrient scarcity, cancer, and the evolution of cooperation.},
journal = {BioEssays : news and reviews in molecular, cellular and developmental biology},
volume = {},
number = {},
pages = {e2000160},
doi = {10.1002/bies.202000160},
pmid = {33165962},
issn = {1521-1878},
abstract = {Since the dawn of molecular biology, cancer therapy has focused on druggable targets. Despite some remarkable successes, cell-level evolution remains a potent antagonist to this approach. We suggest that a deeper understanding of the breakdown of cooperation can synergize the evolutionary and druggable-targets approaches. Complexity requires cooperation, whether between cells of different species (symbiosis) or between cells of the same organism (multicellularity). Both forms of cooperation may be associated with nutrient scarcity, which in turn may be associated with a chemiosmotic metabolism. A variety of examples from modern organisms supports these generalities. Indeed, mammalian cancers-unicellular, glycolytic, and fast-replicating-parallel these examples. Nutrient scarcity, chemiosmosis, and associated signaling may favor cooperation, while under conditions of nutrient abundance a fermentative metabolism may signal the breakdown of cooperation. Manipulating this metabolic milieu may potentiate the effects of targeted therapeutics. Specific opportunities are discussed in this regard, including avicins, a novel plant product.},
}
@article {pmid33162579,
year = {2020},
author = {Jadhav, MS},
title = {Operative procedures performed during SARS-Cov-2 pandemic: Safe for patients and health care workers under appropriate guidelines.},
journal = {Indian journal of anaesthesia},
volume = {64},
number = {9},
pages = {807-809},
pmid = {33162579},
issn = {0019-5049},
}
@article {pmid33161357,
year = {2020},
author = {Efstathiadou, E and Savvas, D and Tampakaki, AP},
title = {Genetic diversity and phylogeny of indigenous rhizobia nodulating faba bean (Vicia faba L.) in Greece.},
journal = {Systematic and applied microbiology},
volume = {43},
number = {6},
pages = {126149},
doi = {10.1016/j.syapm.2020.126149},
pmid = {33161357},
issn = {1618-0984},
abstract = {The genetic diversity and phylogeny of fast-growing rhizobia isolated from root nodules of Vicia faba grown in different geographical regions of Greece were assessed. Although Rhizobium leguminosarum sv. viciae is the most common symbiont of Vicia spp. in European soils, there is no available information on native rhizobia nodulating faba bean in Greece. Seventy bacterial strains were isolated and grouped into sixteen distinct profiles based on BOX-PCR fingerprinting. The phylogenetic affiliation was further defined by sequence analysis of the rrs and multilocus sequence analysis (MLSA) of three housekeeping genes (recA, atpD and gyrB). Fifty-eight isolates were affiliated with recently described genospecies gsF-2, represented by R. laguerreae FB206T, whereas six isolates were closely related to gsB and two isolates might belong to gsA. Two isolates assigned to R. hidalgonense and another two non-nodulating strains could not be assigned to any validly defined species and possibly belong to a new rhizobial lineage. Interestingly, R. laguerreae strains were commonly found at all sampling sites, suggesting that they could be the main symbionts of faba beans in Greek soils. According to the phylogenies of two symbiosis-related genes (nodC and nifH), all nodulating isolates belonged to symbiovar (sv.) viciae harboring four distinct nodC gene haplotypes and they were grouped into two clades together with strains assigned to R. laguerreae and genospecies of R. leguminosarum isolated from other countries and continents. This is the first report that R. hidalgonense strains belong to sv. viciae. No correlation was observed between the nodC haplotypes, geographic origin and chromosomal background of the isolates in the study.},
}
@article {pmid33161208,
year = {2020},
author = {Taerum, SJ and Jasso-Selles, DE and Hileman, JT and De Martini, F and Mizumoto, N and Gile, GH},
title = {Spirotrichonymphea (Parabasalia) symbionts of the termite Paraneotermes simplicicornis.},
journal = {European journal of protistology},
volume = {76},
number = {},
pages = {125742},
doi = {10.1016/j.ejop.2020.125742},
pmid = {33161208},
issn = {1618-0429},
mesh = {Animals ; DNA, Protozoan/genetics ; Isoptera/*parasitology ; Parabasalidea/*classification/genetics/*physiology ; Phylogeny ; RNA, Ribosomal, 18S/genetics ; Species Specificity ; *Symbiosis ; },
abstract = {The desert dampwood termite Paraneotermes simplicicornis harbors several species of obligately symbiotic protists that support its nutrition by fermenting lignocellulose. Among them are three morphotypes with the dexiotropic spiraling flagellar bands characteristic of Spirotrichonymphea (Parabasalia). The largest morphotype, characterized by an elongated cell apex with axial columella and internally positioned spiraling flagellar bands, was previously described as Spirotrichonympha polygyra. A smaller morphotype, with similarly internalized flagellar bands but a more rounded posterior without a protruding axostyle, was previously reported but not named. The smallest morphotype has surface flagellar bands and can attach to other protist cells by its apex. In this study, we combine light microscopy of live specimens and 18S rRNA gene sequencing of individually isolated cells to better understand the diversity of symbionts in P. simplicicornis. We found that S. polygyra branches distantly from true Spirotrichonympha, which are associated with Reticulitermes termites. Thus, we propose the new genus Cuppa to accommodate C. polygyra n. comb. (type species) and the similar but smaller morphotype Cuppa taenia n. sp. The undescribed smallest morphotype can be excluded from all previously described Spirotrichonymphea genera by molecular and behavioral evidence, so we propose Fraterculus simplicicornis n. gen., n. sp., to accommodate this organism.},
}
@article {pmid33159824,
year = {2020},
author = {Locsin, RC and Pepito, JA and Juntasopeepun, P and Constantino, RE},
title = {Transcending human frailties with technological enhancements and replacements: Transhumanist perspective in nursing and healthcare.},
journal = {Nursing inquiry},
volume = {},
number = {},
pages = {e12391},
doi = {10.1111/nin.12391},
pmid = {33159824},
issn = {1440-1800},
support = {//Visiting Professorship Grant/ ; },
abstract = {As human beings age, they become weak, fragile, and feeble. It is a slowly progressing yet complex syndrome in which old age or some disabilities are not prerequisites; neither does loss of human parts lead to frailty among the physically fit older persons. This paper aims to describe the influences of transhumanist perspectives on human-technology enhancements and replacements in the transcendence of human frailties, including those of older persons, in which technology is projected to deliver solutions toward transcending these frailties. Through technologies including genetic screening and other technological manipulations, intelligent machines and augmented humans improve, maintain, and remedy human-linked susceptibilities. Furthermore, other technologies replace parts fabricated through inorganic-mechanical processes such as 3D-printing. Advancing technologies are reaching the summit of technological sophistication contributing to the transhumanist views of being human in a technological world. Technologies enhance the transcendence of human frailties as essential expressions of the symbiosis between human beings and technology in a transcendental world.},
}
@article {pmid33159597,
year = {2020},
author = {Miyamoto, Y and Danilov, AV and Bryanin, SV},
title = {The dominance of Suillus species in ectomycorrhizal fungal communities on Larix gmelinii in a post-fire forest in the Russian Far East.},
journal = {Mycorrhiza},
volume = {},
number = {},
pages = {},
doi = {10.1007/s00572-020-00995-3},
pmid = {33159597},
issn = {1432-1890},
abstract = {Wildfires can negatively affect ectomycorrhizal (EM) fungal communities. However, potential shifts in community structures due to wildfires have rarely been evaluated in the forests of eastern Eurasia, where surface fires are frequent. We investigated EM fungal communities in a Larix gmelinii-dominated forest that burned in 2003 in Zeya, in the Russian Far East. A total of 120 soil samples were collected from burned and adjacent unburned forest sites. The EM fungal root tips were morphotyped and internal transcribed spacer (ITS) sequences were obtained for fungal identification. We detected 147 EM fungal operational taxonomic units, and EM fungal richness was 25% lower at the burned site than at the unburned site. EM fungal composition was characterized by the occurrence of disturbance-adapted fungi (Amphinema and Wilcoxina) at the burned site and late-successional fungi (Lactarius, Russula and Cortinarius) at the unburned site. These findings suggest that the EM fungal communities did not recover to pre-fire levels 16 years after the fire. Suillus species were the dominant EM fungi on L. gmelinii, with greater richness and frequency at the burned site. Both Larix and Suillus exhibit adaptive traits to quickly colonize fire-disturbed habitats. Frequent surface fires common to eastern Eurasia are likely to play important roles in maintaining Larix forests, concomitantly with their closely associated EM fungi.},
}
@article {pmid33158898,
year = {2020},
author = {Jiang, Y and Brandt, BW and Buijs, MJ and Cheng, L and Exterkate, RAM and Crielaard, W and Deng, DM},
title = {Manipulation of saliva-derived microcosm biofilms to resemble dysbiotic subgingival microbiota.},
journal = {Applied and environmental microbiology},
volume = {},
number = {},
pages = {},
doi = {10.1128/AEM.02371-20},
pmid = {33158898},
issn = {1098-5336},
abstract = {Periodontitis is a highly prevalent oral inflammatory disease triggered by dysbiotic subgingival microbiota. For the development of microbiome modulators that can reverse the dysbiotic state and re-establish a health-related microbiota, a high-throughput in vitro multi-species biofilm model is needed. Our aim is to establish a model that resembles a dysbiotic subgingival microbial biofilm by incorporating the major periodontal pathogen Porphyromonas gingivalis into microcosm biofilms cultured from pooled saliva of healthy volunteers. The biofilms were grown for 3, 7, and 10 days and analyzed for their microbial composition by 16S rDNA amplicon sequencing as well as dipeptidyl peptidase IV (DPP4) activity and butyric acid production. The addition of P. gingivalis increased its abundance in saliva-derived microcosm biofilms from 2.7% on day 3 to >50% on day 10, which significantly reduced the Shannon diversity, but did not affect the total number of operational taxonomic units (OTUs). The P. gingivalis-enriched biofilms displayed altered microbial composition as revealed by principle component analysis and reduced interactions among microbial species. Moreover, these biofilms exhibited enhanced DPP4 activity and butyric acid production. In conclusion, by adding P. gingivalis into saliva-derived microcosm biofilms, we established an in vitro pathogen-enriched dysbiotic microbiota, which resembles periodontitis-associated subgingival microbiota in terms of increased P. gingivalis abundance and higher DPP4 activity and butyric acid production. This model may allow for investigating factors that accelerate or hinder microbial shift from symbiosis to dysbiosis and for developing microbiome modulation strategies.IMPORTANCE In line with the new paradigm of the etiology of periodontitis, an inflammatory disorder initiated by dysbiotic subgingival microbiota, novel therapeutic strategies have been proposed, targeting reversing dysbiosis and restoring host-compatible microbiota, rather than eliminating the biofilms unselectively. Thus, appropriate laboratory models are required to evaluate the efficacy of potential microbiome modulators. In the present study, we used the easily obtainable saliva as an inoculum, spiked the microcosm biofilms with the periodontal pathogen Porphyromonas gingivalis, and obtained a P. gingivalis-enriched microbiota, which resembles the in vivo pathogen-enriched subgingival microbiota in severe periodontitis. This biofilm model circumvents the difficulties encountered when using subgingival plaque as the inoculum and achieves microbiota in dysbiotic state in a controlled and reproducible manner, which is required for high-throughput and large scale evaluation of strategies that can potentially modulate microbial ecology.},
}
@article {pmid33158887,
year = {2020},
author = {Shi, Y and Queller, DC and Tian, Y and Zhang, S and Yan, Q and He, Z and He, Z and Wu, C and Wang, C and Shu, L},
title = {The ecology and evolution of amoeba-bacteria interactions.},
journal = {Applied and environmental microbiology},
volume = {},
number = {},
pages = {},
doi = {10.1128/AEM.01866-20},
pmid = {33158887},
issn = {1098-5336},
abstract = {Amoebae are protists that have complicated relationships with bacteria, which cover the whole spectrum of symbiosis. Amoeba-bacteria interactions contribute to the study of predation, symbiosis, pathogenesis, and human health. Given the complexity of their relationships, it is necessary to understand the ecology and evolution of their interactions. In this paper, we provide an updated review of the current understanding of amoeba-bacteria interactions. We start by discussing the diversity of amoebae and their bacterial partners. Besides, we define three types of ecological interactions between amoebae and bacteria and discuss their different outcomes. Finally, we focus on the implications of amoeba-bacteria interactions on human health, horizontal gene transfer, drinking water safety, and the evolution of symbiosis. In conclusion, amoeba-bacteria interactions are excellent model systems to investigate a wide range of scientific questions. Future studies should utilize advanced techniques to address research gaps such as detecting hidden diversity, lack of amoebae genome, and the impacts of amoeba predation on the microbiome.},
}
@article {pmid33158453,
year = {2020},
author = {Van de Guchte, M and Burz, SD and Cadiou, J and Wu, J and Mondot, S and Blottière, HM and Doré, J},
title = {Alternative stable states in the intestinal ecosystem: proof of concept in a rat model and a perspective of therapeutic implications.},
journal = {Microbiome},
volume = {8},
number = {1},
pages = {153},
pmid = {33158453},
issn = {2049-2618},
abstract = {BACKGROUND: Chronic immune-mediated diseases are rapidly expanding and notoriously difficult to cure. Altered relatively stable intestinal microbiota configurations are associated with several of these diseases, and with a possible pre-disease condition (more susceptible to disease development) of the host-microbiota ecosystem. These observations are reminiscent of the behavior of an ecosystem with alternative stable states (different stable configurations that can exist under identical external conditions), and we recently postulated that health, pre-disease and disease represent such alternative states. Here, our aim was to examine if alternative stable states indeed exist in the intestinal ecosystem.
RESULTS: Rats were exposed to varying concentrations of DSS in order to create a wide range of mildly inflammatory conditions, in a context of diet-induced low microbiota diversity. The consequences for the intestinal microbiota were traced by 16S rRNA gene profiling over time, and inflammation of the distal colon was evaluated at sacrifice, 45 days after the last DSS treatment. The results provide the first formal experimental proof for the existence of alternative stable states in the rat intestinal ecosystem, taking both microbiota and host inflammatory status into consideration. The alternative states are host-microbiota ecosystem states rather than independent and dissociated microbiota and host states, and inflammation can prompt stable state-transition. Based on these results, we propose a conceptual model providing new insights in the interplay between host inflammatory status and microbiota status. These new insights call for innovative therapeutic strategies to cure (pre-)disease.
CONCLUSIONS: We provide proof of concept showing the existence of alternative stable states in the rat intestinal ecosystem. We further propose a model which, if validated in humans, will support innovative diagnosis, therapeutic strategy, and monitoring in the treatment of chronic inflammatory conditions. This model provides a strong rationale for the application of combinatorial therapeutic strategies, targeting host and microbiota rather than only one of the two in chronic immune-mediated diseases. Video Abstract.},
}
@article {pmid33153292,
year = {2020},
author = {Egea, MB and Santos, DCD and Oliveira Filho, JG and Ores, JDC and Takeuchi, KP and Lemes, AC},
title = {A review of nondairy kefir products: their characteristics and potential human health benefits.},
journal = {Critical reviews in food science and nutrition},
volume = {},
number = {},
pages = {1-17},
doi = {10.1080/10408398.2020.1844140},
pmid = {33153292},
issn = {1549-7852},
abstract = {Functional foods are foods that, in addition to having nutrients, contain in their composition ingredients that act specifically on body functions associated with the control and reduction of the risk of developing some diseases. In this sense, kefir, a group of microorganisms in symbiosis, mainly yeasts and lactic acid bacteria, stands out. The trend of ingesting kefir has been focused on the development of products that serve specific consumers, such as those who are lactose-intolerant, vegans and vegetarians, and consumers in general who seek to combine the consumption of functional products with the improvement of their health and lifestyle. This overview provides an insight into kefir, presenting the technological process to produce a nondairy beverage and evidence of the benefits of its use to reduce the risk of disease. We also discuss regulatory aspects of products fermented using kefir. Until now, the use of kefir (isolated microorganism, kefiran, or fermented product) has demonstrated the potential to promote an increase in the number of bifidobacteria in the colon and an increase in the glycemic control while reducing the blood cholesterol and balancing the intestinal microbiota, which helps in reducing constipation and diarrhea, improving intestinal permeability, and stimulating and balancing the immune system. However, the literature still has gaps that need to be clarified, such as the consumption dose of kefir or its products to cause some health benefit.},
}
@article {pmid33152013,
year = {2020},
author = {Jerbi, M and Labidi, S and Lounès-Hadj Sahraoui, A and Chaar, H and Ben Jeddi, F},
title = {Higher temperatures and lower annual rainfall do not restrict, directly or indirectly, the mycorrhizal colonization of barley (Hordeum vulgare L.) under rainfed conditions.},
journal = {PloS one},
volume = {15},
number = {11},
pages = {e0241794},
pmid = {33152013},
issn = {1932-6203},
abstract = {Whereas the role of arbuscular mycorrhizal fungi (AMF) in plant growth improvement has been well described in agroecosystems, little is known about the effect of environmental factors on AMF root colonization status of barley, the fourth most important cereal crop all over the world. In order to understand the influence of environmental factors, such as climatic and soil physico-chemical properties, on the spontaneous mycorrhizal ability of barley (Hordeum vulgare L.), a field investigation was conducted in 31 different sites in sub-humid, upper and middle semi-arid areas of Northern Tunisia. Mycorrhizal root colonization of H. vulgare varied considerably among sites. Principal component analysis showed that barley mycorrhization is influenced by both climatic and edaphic factors. A partial least square structural equation modelling (PLS-SEM) revealed that 39% (R²) of the total variation in AMF mycorrhizal rate of barley roots was mainly explained by chemical soil properties and climatic characteristics. Whereas barley root mycorrhizal rates were inversely correlated with soil organic nitrogen (ON), available phosphorus amounts (P), altitude (Z), average annual rainfall (AAR), they were directly correlated with soil pH and temperature. Our results indicated that AMF root colonization of barley was strongly related to climatic characteristics than chemical soil properties. The current study highlights the importance of the PLS-SEM to understand the interactions between climate, soil properties and AMF symbiosis of barley in field conditions.},
}
@article {pmid33151753,
year = {2020},
author = {Starzak, DE and Quinnell, RG and Cook, CB and Davy, SK},
title = {Influence of Symbiont Species on the Glycerol and Glucose Pools in a Model Cnidarian-Dinoflagellate Symbiosis.},
journal = {The Biological bulletin},
volume = {239},
number = {2},
pages = {143-151},
doi = {10.1086/710349},
pmid = {33151753},
issn = {1939-8697},
abstract = {AbstractSymbiotic dinoflagellates in the family Symbiodiniaceae release mobile compounds (e.g., glucose, glycerol, amino acids, and lipids) to their host's tissues. Little is known about how different symbionts affect quantitative and qualitative differences in these compounds. We tested how symbiont identity affects glycerol and glucose pools in the tissues of the sea anemone Exaiptasia pallida ("Aiptasia"). We infected symbiont-free anemones with three different symbiotic dinoflagellates: Breviolum minutum isolated from our Aiptasia stock, B. minutum isolated from a different Aiptasia population, and the free-living Effrenium voratum. We measured free glycerol and glucose levels in host tissues under photosynthetic conditions, as well as metabolite release by these algae when freshly isolated from Aiptasia and incubated in a host tissue homogenate. Anemone tissues containing the stock B. minutum accumulated glycerol at a higher symbiont cell-specific rate than those containing the alternative B. minutum or E. voratum (e.g., at 9 h of light incubation: stock B. minutum, 4.05 × 10-5 nmol per algal cell; alternative B. minutum, 0.90 × 10-5 nmol per algal cell; E. voratum: 1.14 × 10-5 nmol per algal cell). All symbiotic hosts accumulated glucose between 1 and 12 h of light incubation. At 12 h, the symbiont cell-specific glucose content was 6-fold higher in anemone tissues that contained stock B. minutum than in those containing the alternative B. minutum (1.73 × 10-6vs. 0.30 × 10-6 nmol per algal cell, respectively). All freshly isolated algae released glycerol and glucose when incubated in host homogenate except E. voratum, which did not release glycerol. These trends mirrored those in hospite. Our results suggest that, on an algal cell-specific basis, B. minutum isolated from the same Aiptasia stock provided better nutritional support to the host than did the two other algae, though this was not reflected in colonization success, highlighting the underlying complexity of host-symbiont recognition and symbiosis establishment in the cnidarian-dinoflagellate partnership.},
}
@article {pmid33150498,
year = {2020},
author = {Pino-Bodas, R and Stenroos, S},
title = {Global Biodiversity Patterns of the Photobionts Associated with the Genus Cladonia (Lecanorales, Ascomycota).},
journal = {Microbial ecology},
volume = {},
number = {},
pages = {},
doi = {10.1007/s00248-020-01633-3},
pmid = {33150498},
issn = {1432-184X},
support = {FLF program//Royal Botanical Gardens, Kew/ ; Juan de la Cierva-Incorporación 2015-23526//Ministerio de Ciencia, Innovación y Universidades/ ; },
abstract = {The diversity of lichen photobionts is not fully known. We studied here the diversity of the photobionts associated with Cladonia, a sub-cosmopolitan genus ecologically important, whose photobionts belong to the green algae genus Asterochloris. The genetic diversity of Asterochloris was screened by using the ITS rDNA and actin type I regions in 223 specimens and 135 species of Cladonia collected all over the world. These data, added to those available in GenBank, were compiled in a dataset of altogether 545 Asterochloris sequences occurring in 172 species of Cladonia. A high diversity of Asterochloris associated with Cladonia was found. The commonest photobiont lineages associated with this genus are A. glomerata, A. italiana, and A. mediterranea. Analyses of partitioned variation were carried out in order to elucidate the relative influence on the photobiont genetic variation of the following factors: mycobiont identity, geographic distribution, climate, and mycobiont phylogeny. The mycobiont identity and climate were found to be the main drivers for the genetic variation of Asterochloris. The geographical distribution of the different Asterochloris lineages was described. Some lineages showed a clear dominance in one or several climatic regions. In addition, the specificity and the selectivity were studied for 18 species of Cladonia. Potentially specialist and generalist species of Cladonia were identified. A correlation was found between the sexual reproduction frequency of the host and the frequency of certain Asterochloris OTUs. Some Asterochloris lineages co-occur with higher frequency than randomly expected in the Cladonia species.},
}
@article {pmid33147604,
year = {2020},
author = {Euring, D and Janz, D and Polle, A},
title = {Wood properties and transcriptional responses of poplar hybrids in mixed cropping with the nitrogen-fixing species Robinia pseudoacacia.},
journal = {Tree physiology},
volume = {},
number = {},
pages = {},
doi = {10.1093/treephys/tpaa144},
pmid = {33147604},
issn = {1758-4469},
abstract = {Cultivation of fast growing tree species is often confined to marginal land. Mixed cropping with Robinia pseudoacacia, a legume tree species that forms a symbiosis with N2-fixing bacteria, has been proposed to be a measure to improve soil fertility and to achieve beneficial effects on the cocultivated tree species. The goal of our study was to examine the influence of a Robinia mixture on wood chemistry, anatomy, and gene expression in poplar. We hypothesized that annual wood growth is stimulated in species mixtures due to the positive effects of Robinia on N availability and complementary resource use. Alternatively, we hypothesized that competition, especially for water, has negative effects on the wood growth of poplar. We used two commercial biomass clones, Hybride 275 (H275, P. trichocarpa × P. maximowiczii) and Max1 (P. nigra × P. maximowiczii), which were planted at two locations with contrasting soil fertility in monoculture or mixed plots with Robinia to investigate the annual wood increment, wood N and δ13C, wood anatomy (length, cell wall thickness, lumina and frequencies of fibers and vessels) and transcriptional profiles in the developing xylem of 4-year-old stems. In a mixture with Robinia, the annual stem increment was reduced, nitrogen in wood was enhanced, δ13C in wood was decreased, vessel and fiber frequencies were increased, and fiber lengths and fiber lumina were decreased. Transcriptional profiles showed stronger differences between the genotypes and sites than between mono and mixed cultivation. The transcriptional abundances of only one gene (the putative nitrate transporter, NRT1.2) and one gene ontology term ("immune system process") were significantly enriched in wood-forming tissues in response to the mixture, irrespective of the poplar genotype and growth location. Weighted gene coexpression network analyses extracted gene modules that linked wood nitrogen mainly to vessel traits and wood δ13C with fiber traits. Collectively, molecular and anatomical changes in poplar wood suggest beneficial effects on the water and N supply in response to the mixture with Robinia. These alterations may render poplars less drought-susceptible. However, these benefits are accompanied by a reduced wood increment, emphasizing that other critical factors, presumably light competition or allelopathic effects, overrule a potential growth stimulation.},
}
@article {pmid33144618,
year = {2020},
author = {Yahiro, K and Ogura, K and Goto, Y and Iyoda, S and Kobayashi, T and Takeuchi, H and Ohnishi, M and Moss, J},
title = {Subtilase cytotoxin induces a novel form of Lipocalin 2, which promotes Shiga-toxigenic Escherichia coli survival.},
journal = {Scientific reports},
volume = {10},
number = {1},
pages = {18943},
pmid = {33144618},
issn = {2045-2322},
abstract = {Shiga-toxigenic Escherichia coli (STEC) infection causes severe bloody diarrhea, renal failure, and hemolytic uremic syndrome. Recent studies showed global increases in Locus for Enterocyte Effacement (LEE)-negative STEC infection. Some LEE-negative STEC produce Subtilase cytotoxin (SubAB), which cleaves endoplasmic reticulum (ER) chaperone protein BiP, inducing ER stress and apoptotic cell death. In this study, we report that SubAB induces expression of a novel form of Lipocalin-2 (LCN2), and describe its biological activity and effects on apoptotic cell death. SubAB induced expression of a novel LCN2, which was regulated by PRKR-like endoplasmic reticulum kinase via the C/EBP homologous protein pathway. SubAB-induced novel-sized LCN2 was not secreted into the culture supernatant. Increased intracellular iron level by addition of holo-transferrin or FeCl3 suppressed SubAB-induced PARP cleavage. Normal-sized FLAG-tagged LCN2 suppressed STEC growth, but this effect was not seen in the presence of SubAB- or tunicamycin-induced unglycosylated FLAG-tagged LCN2. Our study demonstrates that SubAB-induced novel-sized LCN2 does not have anti-STEC activity, suggesting that SubAB plays a crucial role in the survival of LEE-negative STEC as well as inducing apoptosis of the host cells.},
}
@article {pmid33143304,
year = {2020},
author = {Goicoechea, N},
title = {Mycorrhizal Fungi as Bioprotectors of Crops Against Verticillium Wilt-A Hypothetical Scenario Under Changing Environmental Conditions.},
journal = {Plants (Basel, Switzerland)},
volume = {9},
number = {11},
pages = {},
pmid = {33143304},
issn = {2223-7747},
abstract = {The association that many crops can establish with the arbuscular mycorrhizal fungi (AMF) present in soils can enhance the resistance of the host plants against several pathogens, including Verticillium spp. The increased resistance of mycorrhizal plants is mainly due to the improved nutritional and water status of crops and to enhanced antioxidant metabolism and/or increased production of secondary metabolites in the plant tissues. However, the effectiveness of AMF in protecting their host plants against Verticillium spp. may vary depending on the environmental factors. Some environmental factors, such as the concentration of carbon dioxide in the atmosphere, the availability of soil water and the air and soil temperatures, are predicted to change drastically by the end of the century. The present paper discusses to what extent the climate change may influence the role of AMF in protecting crops against Verticillium-induced wilt, taking into account the current knowledge about the direct and indirect effects that the changing environment can exert on AMF communities in soils and on the symbiosis between crops and AMF, as well as on the development, incidence and impact of diseases caused by soil-borne pathogens.},
}
@article {pmid33143295,
year = {2020},
author = {Ling, J and Guan, H and Liu, L and Tao, J and Li, J and Dong, J and Zhang, S},
title = {The Diversity, Composition, and Putative Functions of Gill-Associated Bacteria of Bathymodiolin Mussel and Vesicomyid Clam from Haima Cold Seep, South China Sea.},
journal = {Microorganisms},
volume = {8},
number = {11},
pages = {},
pmid = {33143295},
issn = {2076-2607},
support = {2018YFC0310005//National Key R&D Program of China/ ; QNLM2016ORP0210//Qingdao National Laboratory for Marine Science and Technology/ ; 91958105//NSF of China/ ; 2019B030302004//Major Program of Guangdong Basic and Applied Research/ ; GML2019ZD0401//Key Special Project for Introduced Talents Team of Southern Marine Science and Engineering Guangdong Laboratory (Guangzhou)/ ; },
abstract = {The Haima cold seep, which is one of the two active cold seeps in the South China Sea, is known for its great ecological importance. The seep bivalves are assumed to depend mainly on their bacterial symbiosis for survival and growth. However, information on the bacterial diversity, composition, and putative function of gill-associated of dominant dwelling animals in Haima cold seep remain elusive. Herein, we adopted a high-throughput sequencing of 16S rRNA gene amplicons, and function prediction methods (Functional Annotation of Prokaryotic Taxa (FAPROTAX) and Phylogenetic Investigation of Communities by Reconstruction of Unobserved States (PICURUSTs)) to purposely illustrate the taxonomic and phylogenetic diversity, composition, and putative functions of the symbionts in bathymodiolin mussel Gigantidas haimaensis (Bivalvia: Mytilidae: Gigantidas) and vesicomyid clam Archivesica marissinica (Bivalvia: Glossoidea: Vesicomyidae). The predominant microbes of both species were Proteobacteria and Gammaproteobacteria on the phylum and class level, respectively. The taxonomic and phylogenetic diversity of gill microbial communities in G. haimaensis were significantly different from those in A. marissinica (p < 0.05). Nine functional groups, including seven carbon-related biogeochemical groups, were identified through the FAPROTAX analysis. However, the most dominant groups for G. haimaensis and A. marissinica were both chemoheterotrophic. G. haimaensis and A. marissinica shared many pathways, however, 16 obtained Kyoto Encyclopedia of Genes and Genomes (KEGG) orthologous groups (42.11%) significantly differed between the two species (p < 0.05). These findings would provide insight into the functions of microbes in the element cycling and energy flow as well as the host-symbiont relationship of bivalves in the Haima cold seep environment.},
}
@article {pmid33143227,
year = {2020},
author = {Petrushin, I and Belikov, S and Chernogor, L},
title = {Cooperative Interaction of Janthinobacterium sp. SLB01 and Flavobacterium sp. SLB02 in the Diseased Sponge Lubomirskiabaicalensis.},
journal = {International journal of molecular sciences},
volume = {21},
number = {21},
pages = {},
pmid = {33143227},
issn = {1422-0067},
support = {19-14-00088//Russian Science Foundation/ ; 0345-2019-0002 (AAAA-A16-116122110066-1)//Siberian Branch, Russian Academy of Sciences/ ; },
abstract = {Endemic freshwater sponges (demosponges, Lubomirskiidae) dominate in Lake Baikal, Central Siberia, Russia. These sponges are multicellular filter-feeding animals that represent a complex consortium of many species of eukaryotes and prokaryotes. In recent years, mass disease and death of Lubomirskia baicalensis has been a significant problem in Lake Baikal. The etiology and ecology of these events remain unknown. Bacteria from the families Flavobacteriaceae and Oxalobacteraceae dominate the microbiomes of diseased sponges. Both species are opportunistic pathogens common in freshwater ecosystems. The aim of our study was to analyze the genomes of strains Janthinobacterium sp. SLB01 and Flavobacterium sp. SLB02, isolated from diseased sponges to identify the reasons for their joint dominance. Janthinobacterium sp. SLB01 attacks other cells using a type VI secretion system and suppresses gram-positive bacteria with violacein, and regulates its own activity via quorum sensing. It produces floc and strong biofilm by exopolysaccharide biosynthesis and PEP-CTERM/XrtA protein expression. Flavobacterium sp. SLB02 utilizes the fragments of cell walls produced by polysaccharides. These two strains have a marked difference in carbohydrate acquisition. We described a possible means of joint occupation of the ecological niche in the freshwater sponge microbial community. This study expands the understanding of the symbiotic relationship of microorganisms with freshwater Baikal sponges.},
}
@article {pmid33142812,
year = {2020},
author = {Genitsaris, S and Stefanidou, N and Leontidou, K and Matsi, T and Karamanoli, K and Mellidou, I},
title = {Bacterial Communities in the Rhizosphere and Phyllosphere of Halophytes and Drought-Tolerant Plants in Mediterranean Ecosystems.},
journal = {Microorganisms},
volume = {8},
number = {11},
pages = {},
pmid = {33142812},
issn = {2076-2607},
support = {705//Hellenic Foundation for Research and Innovation/ ; 705//General Secretariat for Research and Technology/ ; },
abstract = {The aim of the study was to investigate the bacterial community diversity and structure by means of 16S rRNA gene high-throughput amplicon sequencing, in the rhizosphere and phyllosphere of halophytes and drought-tolerant plants in Mediterranean ecosystems with different soil properties. The locations of the sampled plants included alkaline, saline-sodic soils, acidic soils, and the volcanic soils of Santorini Island, differing in soil fertility. Our results showed high bacterial richness overall with Proteobacteria and Actinobacteria dominating in terms of OTUs number and indicated that variable bacterial communities differed depending on the plant's compartment (rhizosphere and phyllosphere), the soil properties and location of sampling. Furthermore, a shared pool of generalist bacterial taxa was detected independently of sampling location, plant species, or plant compartment. We conclude that the rhizosphere and phyllosphere of native plants in stressed Mediterranean ecosystems consist of common bacterial assemblages contributing to the survival of the plant, while at the same time the discrete soil properties and environmental pressures of each habitat drive the development of a complementary bacterial community with a distinct structure for each plant and location. We suggest that this trade-off between generalist and specialist bacterial community is tailored to benefit the symbiosis with the plant.},
}
@article {pmid33142139,
year = {2020},
author = {Soares, MO and Matos, E and Lucas, C and Rizzo, L and Allcock, L and Rossi, S},
title = {Microplastics in corals: An emergent threat.},
journal = {Marine pollution bulletin},
volume = {161},
number = {Pt A},
pages = {111810},
doi = {10.1016/j.marpolbul.2020.111810},
pmid = {33142139},
issn = {1879-3363},
mesh = {Animals ; *Anthozoa ; Coral Reefs ; Microplastics ; Plastics ; *Water Pollutants, Chemical/analysis ; },
abstract = {This article seeks to present a summary of knowledge and thus improve awareness of microplastic impacts on corals. Recent research suggests that microplastics have a variety of species-specific impacts. Among them, a reduced growth, a substantial decrease of detoxifying and immunity enzymes, an increase in antioxidant enzyme activity, high production of mucus, reduction of fitness, and negative effects on coral-Symbiodiniaceae relationships have been highlighted in recent papers. In addition to this, tissue necrosis, lower fertilization success, alteration of metabolite profiles, energetic costs, decreased skeletal growth and calcification, and coral bleaching have been observed under significant concentrations of microplastics. Furthermore, impairment of feeding performance and food intake, changes in photosynthetic performance and increased exposure to contaminants, pathogens and other harmful compounds have also been found. In conclusion, microplastics may cause a plethora of impacts on corals in shallow, mesophotic, and deep-sea zones at different latitudes; underlining an emerging threat globally.},
}
@article {pmid33141816,
year = {2020},
author = {Moriano-Gutierrez, S and Bongrand, C and Essock-Burns, T and Wu, L and McFall-Ngai, MJ and Ruby, EG},
title = {The noncoding small RNA SsrA is released by Vibrio fischeri and modulates critical host responses.},
journal = {PLoS biology},
volume = {18},
number = {11},
pages = {e3000934},
pmid = {33141816},
issn = {1545-7885},
support = {P20 GM125508/GM/NIGMS NIH HHS/United States ; R01 AI050661/AI/NIAID NIH HHS/United States ; R01 GM135254/GM/NIGMS NIH HHS/United States ; R01 OD011024/OD/NIH HHS/United States ; R37 AI050661/AI/NIAID NIH HHS/United States ; },
abstract = {The regulatory noncoding small RNAs (sRNAs) of bacteria are key elements influencing gene expression; however, there has been little evidence that beneficial bacteria use these molecules to communicate with their animal hosts. We report here that the bacterial sRNA SsrA plays an essential role in the light-organ symbiosis between Vibrio fischeri and the squid Euprymna scolopes. The symbionts load SsrA into outer membrane vesicles, which are transported specifically into the epithelial cells surrounding the symbiont population in the light organ. Although an SsrA-deletion mutant (ΔssrA) colonized the host to a normal level after 24 h, it produced only 2/10 the luminescence per bacterium, and its persistence began to decline by 48 h. The host's response to colonization by the ΔssrA strain was also abnormal: the epithelial cells underwent premature swelling, and host robustness was reduced. Most notably, when colonized by the ΔssrA strain, the light organ differentially up-regulated 10 genes, including several encoding heightened immune-function or antimicrobial activities. This study reveals the potential for a bacterial symbiont's sRNAs not only to control its own activities but also to trigger critical responses promoting homeostasis in its host. In the absence of this communication, there are dramatic fitness consequences for both partners.},
}
@article {pmid33141350,
year = {2020},
author = {Hakim, S and Imran, A and Mirza, MS},
title = {Phylogenetic diversity analysis reveals Bradyrhizobium yuanmingense and Ensifer aridi as major symbionts of mung bean (Vigna radiata L.) in Pakistan.},
journal = {Brazilian journal of microbiology : [publication of the Brazilian Society for Microbiology]},
volume = {},
number = {},
pages = {},
doi = {10.1007/s42770-020-00397-9},
pmid = {33141350},
issn = {1678-4405},
abstract = {The present study was carried out to evaluate the diversity of rhizobia associated with nodules of mung bean in Pakistan, because this information is necessary for inoculum development. Based on sequence analysis of 16S rRNA gene of thirty-one bacteria, 11 were assigned to genus Bradyrhizobium, 17 to Ensifer, and 3 to Rhizobium. Phylogenetic analyses on the basis of 16S-23S ITS region, atpD, recA, nifH, and nodA of representative strains revealed that B. yuanmingense is the predominant species distributed throughout different mung bean-growing areas. Among the fast-growing rhizobia, Ensifer aridi was predominant in Faisalabad, Layyah, and Rawalpindi, while E. meliloti in Thal desert. Sequence variations and phylogeny of nifH and nodA genes suggested that these genes might have been co-evolved with the housekeeping genes and maintained by vertical gene transfer in rhizobia detected in the present study. Host infectivity assay revealed the successful nodulation of host by rhizobia related to genera Bradyrhizobium, Ensifer and Rhizobium. Among all, Bradyrhizobium and Ensifer spp. inoculation exhibited a significantly higher number of nodules (11-34 nodules plant-1) and nitrogenase activity (nodule ARA 60-110 μmol g-1 h-1). Contrary to the previous studies, our data reveal that B. yuanmingense and E. aridi are predominant species forming effective nodules in mung bean in Pakistan. Furthermore, to the best of our knowledge, this is the first report showing the effective symbiosis of E. aridi, E. meliloti, and Rhizobium pusense with mung bean. The diversity of rhizobia in different habitats revealed in the present study will contribute towards designing site-specific inocula for mung bean.},
}
@article {pmid33139881,
year = {2020},
author = {Neubacher, N and Tobias, NJ and Huber, M and Cai, X and Glatter, T and Pidot, SJ and Stinear, TP and Lütticke, AL and Papenfort, K and Bode, HB},
title = {Symbiosis, virulence and natural-product biosynthesis in entomopathogenic bacteria are regulated by a small RNA.},
journal = {Nature microbiology},
volume = {5},
number = {12},
pages = {1481-1489},
doi = {10.1038/s41564-020-00797-5},
pmid = {33139881},
issn = {2058-5276},
support = {EXC 2051//Deutsche Forschungsgemeinschaft (German Research Foundation)/ ; SFB 902//Deutsche Forschungsgemeinschaft (German Research Foundation)/ ; StG-758212//EC | EU Framework Programme for Research and Innovation H2020 | H2020 Priority Excellent Science | H2020 European Research Council (H2020 Excellent Science - European Research Council)/ ; },
abstract = {Photorhabdus and Xenorhabdus species have mutualistic associations with nematodes and an entomopathogenic stage1,2 in their life cycles. In both stages, numerous specialized metabolites are produced that have roles in symbiosis and virulence3,4. Although regulators have been implicated in the regulation of these specialized metabolites3,4, how small regulatory RNAs (sRNAs) are involved in this process is not clear. Here, we show that the Hfq-dependent sRNA, ArcZ, is required for specialized metabolite production in Photorhabdus and Xenorhabdus. We discovered that ArcZ directly base-pairs with the mRNA encoding HexA, which represses the expression of specialized metabolite gene clusters. In addition to specialized metabolite genes, we show that the ArcZ regulon affects approximately 15% of all transcripts in Photorhabdus and Xenorhabdus. Thus, the ArcZ sRNA is crucial for specialized metabolite production in Photorhabdus and Xenorhabdus species and could become a useful tool for metabolic engineering and identification of commercially relevant natural products.},
}
@article {pmid33138319,
year = {2020},
author = {Boilard, A and Dubé, CE and Gruet, C and Mercière, A and Hernandez-Agreda, A and Derome, N},
title = {Defining Coral Bleaching as a Microbial Dysbiosis within the Coral Holobiont.},
journal = {Microorganisms},
volume = {8},
number = {11},
pages = {},
pmid = {33138319},
issn = {2076-2607},
support = {6333//Natural Sciences and Engineering Research Council of Canada/ ; },
abstract = {Coral microbiomes are critical to holobiont health and functioning, but the stability of host-microbial interactions is fragile, easily shifting from eubiosis to dysbiosis. The heat-induced breakdown of the symbiosis between the host and its dinoflagellate algae (that is, "bleaching"), is one of the most devastating outcomes for reef ecosystems. Yet, bleaching tolerance has been observed in some coral species. This review provides an overview of the holobiont's diversity, explores coral thermal tolerance in relation to their associated microorganisms, discusses the hypothesis of adaptive dysbiosis as a mechanism of environmental adaptation, mentions potential solutions to mitigate bleaching, and suggests new research avenues. More specifically, we define coral bleaching as the succession of three holobiont stages, where the microbiota can (i) maintain essential functions for holobiont homeostasis during stress and/or (ii) act as a buffer to mitigate bleaching by favoring the recruitment of thermally tolerant Symbiodiniaceae species (adaptive dysbiosis), and where (iii) environmental stressors exceed the buffering capacity of both microbial and dinoflagellate partners leading to coral death.},
}
@article {pmid33137653,
year = {2020},
author = {Ryan, DG and Frezza, C and O'Neill, LA},
title = {TCA cycle signalling and the evolution of eukaryotes.},
journal = {Current opinion in biotechnology},
volume = {68},
number = {},
pages = {72-88},
doi = {10.1016/j.copbio.2020.09.014},
pmid = {33137653},
issn = {1879-0429},
support = {MC_UU_12022/6/MRC_/Medical Research Council/United Kingdom ; },
abstract = {A major question remaining in the field of evolutionary biology is how prokaryotic organisms made the leap to complex eukaryotic life. The prevailing theory depicts the origin of eukaryotic cell complexity as emerging from the symbiosis between an α-proteobacterium, the ancestor of present-day mitochondria, and an archaeal host (endosymbiont theory). A primary contribution of mitochondria to eukaryogenesis has been attributed to the mitochondrial genome, which enabled the successful internalisation of bioenergetic membranes and facilitated remarkable genome expansion. It has also been postulated that a key contribution of the archaeal host during eukaryogenesis was in providing 'archaeal histones' that would enable compaction and regulation of an expanded genome. Yet, how the communication between the host and the symbiont evolved is unclear. Here, we propose an evolutionary concept in which mitochondrial TCA cycle signalling was also a crucial player during eukaryogenesis enabling the dynamic control of an expanded genome via regulation of DNA and histone modifications. Furthermore, we discuss how TCA cycle remodelling is a common evolutionary strategy invoked by eukaryotic organisms to coordinate stress responses and gene expression programmes, with a particular focus on the TCA cycle-derived metabolite itaconate.},
}
@article {pmid33136520,
year = {2020},
author = {Li, Y and Skelton, J and Adams, S and Hattori, Y and Smith, ME and Hulcr, J},
title = {The Ambrosia Beetle Sueus niisimai (Scolytinae: Hyorrhynchini) is Associated with the Canker Disease Fungus Diatrypella japonica (Xylariales).},
journal = {Plant disease},
volume = {104},
number = {12},
pages = {3143-3150},
doi = {10.1094/PDIS-03-20-0482-RE},
pmid = {33136520},
issn = {0191-2917},
mesh = {Ambrosia ; Animals ; *Coleoptera ; *Disease ; Japan ; Phylogeny ; Plant Diseases ; Southeastern United States ; *Weevils ; *Xylariales ; },
abstract = {Ambrosia beetles in the subtribe Hyorrhynchini are one example of an entire ambrosia beetle lineage whose fungi have never been studied. Here, we identify one dominant fungus associated with a widespread Asian hyorrhynchine beetle Sueus niisimai. This fungus was consistently isolated from beetle galleries from multiple collections. Phylogenetic analyses of combined ITS rDNA and β-tubulin sequences identified the primary fungal symbiont as Diatrypella japonica Higuchi, Nikaido & Hattori (Diatrypaceae, Xylariales, Sordariomycetes), which was recently described as a pathogen of sycamore (Platanus spp.) in Japan. To assess the invasion potential of this beetle-fungus interaction into the U.S., we have investigated the pathogenicity of two D. japonica strains on four species of healthy landscape trees native to the southeastern United States. Only Shumard oak (Quercus shumardii) responded with lesions significantly greater than the control inoculations, but there was no observable dieback or tree mortality. Although disease symptoms were not as prominent as in previous studies of the same fungus in Japan, routine reisolation from the inoculation point suggests that this species is capable of colonizing healthy sapwood of several tree species. Our study shows that the geographical area of its distribution is broader in Asia and potentially includes many hosts of its polyphagous vector. We conclude that the Sueus-Diatrypella symbiosis has high invasion potential but low damage potential, at least on young trees during the growing season.},
}
@article {pmid33133783,
year = {2020},
author = {Sarmiento-López, LG and López-Meyer, M and Sepúlveda-Jiménez, G and Cárdenas, L and Rodríguez-Monroy, M},
title = {Photosynthetic performance and stevioside concentration are improved by the arbuscular mycorrhizal symbiosis in Stevia rebaudiana under different phosphate concentrations.},
journal = {PeerJ},
volume = {8},
number = {},
pages = {e10173},
pmid = {33133783},
issn = {2167-8359},
abstract = {In plants, phosphorus (P) uptake occurs via arbuscular mycorrhizal (AM) symbiosis and through plant roots. The phosphate concentration is known to affect colonization by AM fungi, and the effect depends on the plant species. Stevia rebaudiana plants are valuable sources of sweetener compounds called steviol glycosides (SGs), and the principal components of SGs are stevioside and rebaudioside A. However, a detailed analysis describing the effect of the phosphate concentration on the colonization of AM fungi in the roots and the relationship of these factors to the accumulation of SGs and photochemical performance has not been performed; such an analysis was the aim of this study. The results indicated that low phosphate concentrations (20 and 200 µM KH2PO4) induced a high percentage of colonization by Rhizophagus irregularis in the roots of S. rebaudiana, while high phosphate concentrations (500 and 1,000 µM KH2PO4) reduced colonization. The morphology of the colonization structure is a typical Arum-type mycorrhiza, and a mycorrhiza-specific phosphate transporter was identified. Colonization with low phosphate concentrations improved plant growth, chlorophyll and carotenoid concentration, and photochemical performance. The transcription of the genes that encode kaurene oxidase and glucosyltransferase (UGT74G1) was upregulated in colonized plants at 200 µM KH2PO4, which was consistent with the observed patterns of stevioside accumulation. In contrast, at 200 µM KH2PO4, the transcription of UGT76G1 and the accumulation of rebaudioside A were higher in noncolonized plants than in colonized plants. These results indicate that a low phosphate concentration improves mycorrhizal colonization and modulates the stevioside and rebaudioside A concentration by regulating the transcription of the genes that encode kaurene oxidase and glucosyltransferases, which are involved in stevioside and rebaudioside A synthesis in S. rebaudiana.},
}
@article {pmid33130897,
year = {2020},
author = {Peng, Z and Chen, H and Tan, L and Shu, H and Varshney, RK and Zhou, Z and Zhao, Z and Luo, Z and Chitikineni, A and Wang, L and Maku, J and López, Y and Gallo, M and Zhou, H and Wang, J},
title = {Natural Polymorphisms in a Pair of NSP2 Homoeologs Can Cause Loss of Nodulation in Peanut.},
journal = {Journal of experimental botany},
volume = {},
number = {},
pages = {},
doi = {10.1093/jxb/eraa505},
pmid = {33130897},
issn = {1460-2431},
abstract = {Microbial symbiosis in legumes is achieved through nitrogen-fixing root nodules, which is important for sustainable agriculture. The molecular mechanisms underlying development of root nodules in polyploid legume crops are largely understudied. Through map-based cloning and QTL-seq approaches, we identified a pair of homoeologous GRAS transcription factor genes, Nodulation Signaling Pathway 2 (AhNSP2-B07 or Nb) and AhNSP2-A08 (Na), controlling nodulation in cultivated peanut (Arachis hypogaea L.), an allotetraploid legume crop, which exhibited non-Mendelian and Mendelian inheritance, respectively. The segregation of nodulation in the progeny of Nananbnb genotypes followed a 3:1 Mendelian ratio, in contrast to the 5:3 ~ 1:1 non-Mendelian ratio for nanaNbnb genotypes. Additionally, a much higher frequency of the nb allele (13%) than the na allele (4%) exists in the peanut germplasm collection, suggesting that Nb is less essential than Na in nodule organogenesis. Our findings provided the genetic basis of naturally occurred non-nodulating peanut plants, which can be potentially used for nitrogen fixation improvement in peanut. Furthermore, the results provided implications and insights into the evolution of homoeologous genes in allopolyploid species.},
}
@article {pmid33130893,
year = {2020},
author = {Fedorova, EE and de la Peña, TC and Lara-Dampier, V and Trifonova, NA and Kulikova, O and Pueyo, JJ and Lucas, MM},
title = {Potassium content diminishes in infected cells of Medicago truncatula nodules due to the mislocation of channels MtAKT1 and MtSKOR/GORK.},
journal = {Journal of experimental botany},
volume = {},
number = {},
pages = {},
doi = {10.1093/jxb/eraa508},
pmid = {33130893},
issn = {1460-2431},
abstract = {Rhizobia establish a symbiotic relationship with legumes that results in the formation of root nodules, where bacteria encapsulated by a membrane of plant origin (symbiosomes), convert atmospheric nitrogen into ammonia. Nodules are more sensitive to ionic stresses than the host plant itself. We hypothesize that such a high vulnerability might be due to defects in ion balance in the infected tissue. Low temperature-scanning electron microscopy (LTSEM) and X-ray microanalysis of Medicago truncatula nodules revealed a potassium (K+) decrease in symbiosomes and vacuoles during the lifespan of infected cells. To clarify K+ homeostasis in the nodule, we performed phylogenetic and gene expression analyses, confocal and electron microscopy localization of two key plant Shaker K+ channels, AKT1 and SKOR/GORK.Phylogenetic analyses showed that the genome of some legume species, including the Medicago genus, contained one SKOR/GORK and one AKT1 gene copy, while other species contained more than one copy of each gene. Localization studies revealed mistargeting and partial depletion of both channels from the plasma membrane of M. truncatula mature nodule infected cells that might compromise ion transport. We propose that root nodule infected cells do have defects in K+ balance due to mislocation of some plant ion channels, as compared with non-infected cells. The putative consequences are discussed.},
}
@article {pmid33130852,
year = {2020},
author = {Ahmad, MZ and Zhang, Y and Zeng, X and Li, P and Wang, X and Benedito, VA and Zhao, J},
title = {Isoflavone malonyl-CoA acyltransferase GmMaT2 is involved in nodulation of soybean (Glycine max) by modifying synthesis and secretion of isoflavones.},
journal = {Journal of experimental botany},
volume = {},
number = {},
pages = {},
doi = {10.1093/jxb/eraa511},
pmid = {33130852},
issn = {1460-2431},
abstract = {Malonyl-CoA:flavonoid acyltransferases (MaT) modify isoflavones, but only a few have been characterized for activity and assigned to specific physiological processes. Legume roots exude isoflavone malonates into the rhizosphere, where they are hydrolyzed into isoflavone aglycones. Soybean GmMaT2 was highly expressed in seeds, root hairs, and nodules. GmMaT2 and GmMaT4 recombinant enzymes used isoflavone 7-O-glucosides as acceptors and malonyl-CoA as an acyl donor to generate isoflavone glucoside malonates. GmMaT2 had higher activity towards isoflavone glucosides than GmMaT4. Overexpression (OE) in hairy roots of GmMaT2 and 4 produced more malonyldaidzin, malonylgenistin, and malonylglycitin, and resulted in more nodules than control. However, only GmMaT2 knockdown (KD) hairy roots showed reduced levels of malonyldaidzin, malonylgenistin, and malonylglycitin, and likewise, reduced nodule numbers. These were consistent with the up-regulation of only GmMaT2 by rhizobial infection, and higher expression levels of early nodulation genes in GmMaT2- and 4-OE, but lower only in GmMaT2-KD roots compared to control roots. Higher malonyl isoflavonoid levels in transgenic hairy roots were associated with higher levels of isoflavones in root exudates and more nodules, and vice versa. We posit that GmMaT2 participates in soybean nodulation by catalyzing isoflavone malonylation and affecting malonyl isoflavone secretion for activation of Nod factor and nodulation.},
}
@article {pmid33129085,
year = {2021},
author = {Park, JH and Chandrasekhar, K and Jeon, BH and Jang, M and Liu, Y and Kim, SH},
title = {State-of-the-art technologies for continuous high-rate biohydrogen production.},
journal = {Bioresource technology},
volume = {320},
number = {Pt A},
pages = {124304},
doi = {10.1016/j.biortech.2020.124304},
pmid = {33129085},
issn = {1873-2976},
mesh = {Bacteria/genetics ; *Bioreactors ; Fermentation ; *Hydrogen ; RNA, Ribosomal, 16S/genetics ; },
abstract = {Dark fermentation is a technically feasible technology for achieving carbon dioxide-free hydrogen production. This review presents the current findings on continuous hydrogen production using dark fermentation. Several operational strategies and reactor configurations have been suggested. The formation of attached mixed-culture microorganisms is a typical prerequisite for achieving high production rate, hydrogen yield, and resilience. To date, fixed-bed reactors and dynamic membrane bioreactors yielded higher biohydrogen performance than other configurations. The symbiosis between H2-producing bacteria and biofilm-forming bacteria was essential to avoid washout and maintain the high loading rates and hydrogenic metabolic flux. Recent research has initiated a more in-depth comparison of microbial community changes during dark fermentation, primarily with computational science techniques based on 16S rRNA gene sequencing investigations. Future techno-economic analysis of dark fermentative biohydrogen production and perspectives on unraveling mitigation mechanisms induced by attached microorganisms in dark fermentation processes are further discussed.},
}
@article {pmid33127381,
year = {2020},
author = {Hashiguchi, H and Tsukamoto, Y and Ogawa, M and Tashima, Y and Takeuchi, H and Nakamura, M and Kawashima, H and Fujishiro, M and Okajima, T},
title = {Glycoproteomic analysis identifies cryptdin-related sequence 1 as O-glycosylated protein modified with α1,2-fucose in the small intestine.},
journal = {Archives of biochemistry and biophysics},
volume = {695},
number = {},
pages = {108653},
doi = {10.1016/j.abb.2020.108653},
pmid = {33127381},
issn = {1096-0384},
mesh = {Animals ; Fucose/*metabolism ; Glycoproteins/*metabolism ; Glycosylation ; Intestine, Small/*metabolism ; Mice ; Paneth Cells/*metabolism ; Protein Precursors/*metabolism ; *Proteomics ; },
abstract = {The modification of galactose with α1,2-fucose is involved in symbiosis with intestinal bacteria and elimination of pathogenic bacteria. It is postulated that α1,2-fucosylated mucin secreted from goblet cells is involved in defending an organism against infections, but the detailed molecular mechanisms are yet to be elucidated. It was previously reported that Paneth cells of the small intestine were positive for UEA-1 lectin staining. However, glycoproteins in Paneth cells carrying α1,2-fucose have not yet been identified. Glycoproteomic analysis of ileal lysates identified 3212 O-linked and 2962 N-linked glycopeptides. In particular, cryptdin-related sequence 1 (CRS1) expressed in Paneth cells was found to be α1,2-fucosylated. Unlike other antimicrobial α-defensin proteins, CRS1 contains unique Thr residues, which are modified with O-glycans, with 3HexNAc2Hex1Fuc1NeuAc being the main glycoform. Identification of α1,2-fucose on the O-glycans of CRS1 expressed in Paneth cells will pave the way for a mechanistic understanding of α1,2-fucose-dependent symbiosis with intestinal bacteria and elimination of pathogenic bacteria in the intestine.},
}
@article {pmid33126720,
year = {2020},
author = {Lebedeva, M and Azarakhsh, M and Yashenkova, Y and Lutova, L},
title = {Nitrate-Induced CLE Peptide Systemically Inhibits Nodulation in Medicago truncatula.},
journal = {Plants (Basel, Switzerland)},
volume = {9},
number = {11},
pages = {},
pmid = {33126720},
issn = {2223-7747},
support = {16-16-10011//Russian Scientific Foundation/ ; 20-016-00129//Russian Foundation for Basic Research/ ; 19-016-00177//Russian Foundation for Basic Research/ ; ID 60256785//Saint-Petersburg State University/ ; },
abstract = {Legume plants form nitrogen-fixing nodules in symbiosis with soil bacteria rhizobia. The number of symbiotic nodules is controlled at the whole-plant level with autoregulation of nodulation (AON), which includes a shoot-acting CLV1-like receptor kinase and mobile CLE (CLAVATA3/ENDOSPERM SURROUNDING REGION-related) peptides that are produced in the root in response to rhizobia inoculation. In addition to rhizobia-induced CLE peptides, nitrate-induced CLE genes have been identified in Lotus japonicus and Glycine max, which inhibited nodulation when overexpressed. However, nitrate-induced CLE genes that systemically suppress nodulation in AON-dependent manner have not been identified in Medicago truncatula. Here, we found that MtCLE35 expression is activated by both rhizobia inoculation and nitrate treatment in M. truncatula, similarly to L. japonicus CLE genes. Moreover, we found that MtCLE35 systemically suppresses nodulation in AON-dependent manner, suggesting that MtCLE35 may mediate nitrate-induced inhibition of nodulation in M. truncatula.},
}
@article {pmid33126019,
year = {2020},
author = {Li, Z and Mertens, KN and Gottschling, M and Gu, H and Söhner, S and Price, AM and Marret, F and Pospelova, V and Smith, KF and Carbonell-Moore, C and Nézan, E and Bilien, G and Shin, HH},
title = {Taxonomy and Molecular Phylogenetics of Ensiculiferaceae, fam. nov. (Peridiniales, Dinophyceae), with Consideration of their Life-history.},
journal = {Protist},
volume = {171},
number = {5},
pages = {125759},
doi = {10.1016/j.protis.2020.125759},
pmid = {33126019},
issn = {1618-0941},
mesh = {Diatoms/physiology ; Dinoflagellida/*classification/*genetics/parasitology ; *Phylogeny ; Species Specificity ; Symbiosis ; },
abstract = {In the current circumscription, the Thoracosphaeraceae comprise all dinophytes exhibiting calcified coccoid cells produced during their life-history. Species hitherto assigned to Ensiculifera and Pentapharsodinium are mostly based on the monadoid stage of life-history, while the link to the coccoid stage (occasionally treated taxonomically distinct) is not always resolved. We investigated the different life-history stages and DNA sequence data of Ensiculifera mexicana and other species occurring in samples collected from all over the world. Based on concatenated ribosomal RNA gene sequences Ensiculiferaceae represented a distinct peridinalean branch, which showed a distant relationship to other calcareous dinophytes. Both molecular and morphological data (particularly of the coccoid stage) revealed the presence of three distinct clades within Ensiculiferaceae, which may include other dinophytes exhibiting a parasitic life-history stage. At a higher taxonomic level, Ensiculiferaceae showed relationships to parasites and endosymbionts (i.e., Blastodinium and Zooxanthella) as well as to dinophytes harbouring diatoms instead of chloroplasts. These unexpected phylogenetic relationships are corroborated by the presence of five cingular plates in all such taxa, which differs from the six cingular plates of most other Thoracosphaeraceae. We herein describe Ensiculiferaceae, emend the descriptions of Ensiculifera and Pentapharsodinium, erect Matsuokaea and provide several new combinations at the species level.},
}
@article {pmid33124078,
year = {2020},
author = {Van't Padje, A and Werner, GDA and Kiers, ET},
title = {Mycorrhizal fungi control phosphorus value in trade symbiosis with host roots when exposed to abrupt 'crashes' and 'booms' of resource availability.},
journal = {The New phytologist},
volume = {},
number = {},
pages = {},
doi = {10.1111/nph.17055},
pmid = {33124078},
issn = {1469-8137},
support = {//Junior Research Fellowship/ ; 335542//H2020 European Research Council/ ; //Royal Society Newton International Fellowship/ ; //Ammodo Foundation/ ; },
abstract = {Biological market theory provides a conceptual framework to analyse trade strategies in symbiotic partnerships. A key prediction of biological market theory is that individuals can influence resource value - meaning the amount a partner is willing to pay for it - by mediating where and when it is traded. The arbuscular mycorrhizal symbiosis, characterised by roots and fungi trading phosphorus and carbon, shows many features of a biological market. However, it is unknown if or how fungi can control phosphorus value when exposed to abrupt changes in their trade environment. We mimicked an economic 'crash', manually severing part of the fungal network (Rhizophagus irregularis) to restrict resource access, and an economic 'boom' through phosphorus additions. We quantified trading strategies over a 3-wk period using a recently developed technique that allowed us to tag rock phosphate with fluorescing quantum dots of three different colours. We found that the fungus: compensated for resource loss in the 'crash' treatment by transferring phosphorus from alternative pools closer to the host root (Daucus carota); and stored the surplus nutrients in the 'boom' treatment until root demand increased. By mediating from where, when and how much phosphorus was transferred to the host, the fungus successfully controlled resource value.},
}
@article {pmid33123749,
year = {2020},
author = {Fernández Di Pardo, A and Mancini, M and Cravero, V and Gil-Cardeza, ML},
title = {Diagnose of Indigenous Arbuscular Mycorrhizal Communities Associated to Cynara cardunculus L. var. altilis and var. sylvestris.},
journal = {Current microbiology},
volume = {},
number = {},
pages = {},
doi = {10.1007/s00284-020-02257-z},
pmid = {33123749},
issn = {1432-0991},
support = {PUE: 22920160100043CO//Consejo Nacional de Investigaciones Científicas y Técnicas (CONICET)/ ; },
abstract = {Cynara cardunculus L. is a perennial species with high potential for bioenergy production. Arbuscular mycorrhizal symbiosis (AMF) is probably the terrestrial symbiosis most extended on earth. It presence in roots and soils improves plant nutrition and soil quality. Indigenous AMF have developed a variety of modifications to survive in their habitat and thus could serve as potential inoculants for the implantation of plant species in the respective AMF soil habitat. This work aimed to diagnose the status of the AMF symbiosis associated to two cardoon cultivars after a year of growth in a saline soil and in a conventional farming soil. For that purpose we determined AMF parameters in 4 rhizospheric soils and in roots of the cardoon varieties. We found that: (1) the rhizosphere of C. cardunculus var. altilis positively influenced the extraradical mycelium development in the saline soil, (2) the inorganic fertilization history of the conventional farming soil could have had a negative effect on the AMF community and, (3) the intraradical mycelium (IRM) development was extremely low. Our diagnosis suggests that, in order to improve the positive effects of AMF on cardoon growth and soil quality, efforts should be focused on the development of the IRM. In a boarder sense, the implementation of a diagnosis of indigenous AMF communities as a general agronomic practice could become an useful tool to farmers that are willing to potentiate the benefits of AMF on plant growth and soil quality.},
}
@article {pmid33122629,
year = {2020},
author = {Cai, W and Snyder, J and Hastings, A and D'Souza, RM},
title = {Mutualistic networks emerging from adaptive niche-based interactions.},
journal = {Nature communications},
volume = {11},
number = {1},
pages = {5470},
pmid = {33122629},
issn = {2041-1723},
mesh = {Animals ; Biological Evolution ; Computational Biology ; Ecology/*methods ; Ecosystem ; *Food Chain ; *Models, Theoretical ; *Symbiosis ; },
abstract = {Mutualistic networks are vital ecological and social systems shaped by adaptation and evolution. They involve bipartite cooperation via the exchange of goods or services between actors of different types. Empirical observations of mutualistic networks across genres and geographic conditions reveal correlated nested and modular patterns. Yet, the underlying mechanism for the network assembly remains unclear. We propose a niche-based adaptive mechanism where both nestedness and modularity emerge simultaneously as complementary facets of an optimal niche structure. Key dynamical properties are revealed at different timescales. Foremost, mutualism can either enhance or reduce the network stability, depending on competition intensity. Moreover, structural adaptations are asymmetric, exhibiting strong hysteresis in response to environmental change. Finally, at the evolutionary timescale we show that the adaptive mechanism plays a crucial role in preserving the distinctive patterns of mutualism under species invasions and extinctions.},
}
@article {pmid33121045,
year = {2020},
author = {Zamai, L},
title = {Unveiling Human Non-Random Genome Editing Mechanisms Activated in Response to Chronic Environmental Changes: I. Where Might These Mechanisms Come from and What Might They Have Led To?.},
journal = {Cells},
volume = {9},
number = {11},
pages = {},
pmid = {33121045},
issn = {2073-4409},
abstract = {This article challenges the notion of the randomness of mutations in eukaryotic cells by unveiling stress-induced human non-random genome editing mechanisms. To account for the existence of such mechanisms, I have developed molecular concepts of the cell environment and cell environmental stressors and, making use of a large quantity of published data, hypothesised the origin of some crucial biological leaps along the evolutionary path of life on Earth under the pressure of natural selection, in particular, (1) virus-cell mating as a primordial form of sexual recombination and symbiosis; (2) Lamarckian CRISPR-Cas systems; (3) eukaryotic gene development; (4) antiviral activity of retrotransposon-guided mutagenic enzymes; and finally, (5) the exaptation of antiviral mutagenic mechanisms to stress-induced genome editing mechanisms directed at "hyper-transcribed" endogenous genes. Genes transcribed at their maximum rate (hyper-transcribed), yet still unable to meet new chronic environmental demands generated by "pollution", are inadequate and generate more and more intronic retrotransposon transcripts. In this scenario, RNA-guided mutagenic enzymes (e.g., Apolipoprotein B mRNA editing catalytic polypeptide-like enzymes, APOBECs), which have been shown to bind to retrotransposon RNA-repetitive sequences, would be surgically targeted by intronic retrotransposons on opened chromatin regions of the same "hyper-transcribed" genes. RNA-guided mutagenic enzymes may therefore "Lamarkianly" generate single nucleotide polymorphisms (SNP) and gene copy number variations (CNV), as well as transposon transposition and chromosomal translocations in the restricted areas of hyper-functional and inadequate genes, leaving intact the rest of the genome. CNV and SNP of hyper-transcribed genes may allow cells to surgically explore a new fitness scenario, which increases their adaptability to stressful environmental conditions. Like the mechanisms of immunoglobulin somatic hypermutation, non-random genome editing mechanisms may generate several cell mutants, and those codifying for the most environmentally adequate proteins would have a survival advantage and would therefore be Darwinianly selected. Non-random genome editing mechanisms represent tools of evolvability leading to organismal adaptation including transgenerational non-Mendelian gene transmission or to death of environmentally inadequate genomes. They are a link between environmental changes and biological novelty and plasticity, finally providing a molecular basis to reconcile gene-centred and "ecological" views of evolution.},
}
@article {pmid33120157,
year = {2021},
author = {da Silva Fonseca, J and Mies, M and Paranhos, A and Taniguchi, S and Güth, AZ and Bícego, MC and Marques, JA and Fernandes de Barros Marangoni, L and Bianchini, A},
title = {Isolated and combined effects of thermal stress and copper exposure on the trophic behavior and oxidative status of the reef-building coral Mussismilia harttii.},
journal = {Environmental pollution (Barking, Essex : 1987)},
volume = {268},
number = {Pt B},
pages = {115892},
doi = {10.1016/j.envpol.2020.115892},
pmid = {33120157},
issn = {1873-6424},
mesh = {Animals ; *Anthozoa ; Copper/toxicity ; Coral Reefs ; Oxidation-Reduction ; Oxidative Stress ; Symbiosis ; },
abstract = {Global warming and local disturbances such as pollution cause several impacts on coral reefs. Among them is the breakdown of the symbiosis between host corals and photosynthetic symbionts, which is often a consequence of oxidative stress. Therefore, we investigated if the combined effects of thermal stress and copper (Cu) exposure change the trophic behavior and oxidative status of the reef-building coral Mussismilia harttii. Coral fragments were exposed in a mesocosm system to three temperatures (25.0, 26.6 and 27.3 °C) and three Cu concentrations (2.9, 5.4 and 8.6 μg L-1). Samples were collected after 4 and 12 days of exposure. We then (i) performed fatty acid analysis by gas chromatography-mass spectrometry to quantify changes in stearidonic acid and docosapentaenoic acid (autotrophy markers) and cis-gondoic acid (heterotrophy marker), and (ii) assessed the oxidative status of both host and symbiont through analyses of lipid peroxidation (LPO) and total antioxidant capacity (TAC). Our findings show that trophic behavior was predominantly autotrophic and remained unchanged under individual and combined stressors for both 4- and 12-day experiments; for the latter, however, there was an increase in the heterotrophy marker. Results also show that 4 days was not enough to trigger changes in LPO or TAC for both coral and symbiont. However, the 12-day experiment showed a reduction in symbiont LPO associated with thermal stress alone, and the combination of stressors increased their TAC. For the coral, the isolated effects of increase in Cu and temperature led to an increase in LPO. The effects of combined stressors on trophic behavior and oxidative status were not much different than those from the isolated effects of each stressor. These findings highlight that host and symbionts respond differently to stress and are relevant as they show the physiological response of individual holobiont compartments to both global and local stressors.},
}
@article {pmid33118266,
year = {2020},
author = {Mashiguchi, K and Seto, Y and Yamaguchi, S},
title = {Strigolactone biosynthesis, transport and perception.},
journal = {The Plant journal : for cell and molecular biology},
volume = {},
number = {},
pages = {},
doi = {10.1111/tpj.15059},
pmid = {33118266},
issn = {1365-313X},
support = {//Takeda Science Foundation/ ; //Yamada Science Foundation/ ; //The Mitsubishi Foundation/ ; 2020-90//International Collaborative Research Program of Institute for Chemical Research, Kyoto University/ ; //Kato Memorial Bioscience Foundation/ ; 17H06474//JSPS KAKENHI/ ; 19H02892//JSPS KAKENHI/ ; 19K05852//JSPS KAKENHI/ ; },
abstract = {Strigolactones (SLs) are plant hormones that regulate diverse developmental processes and environmental responses. They are also known to be root-derived chemical signals that regulate symbiotic and parasitic interactions with arbuscular mycorrhizal fungi and root parasitic plants, respectively. Since the discovery of the hormonal function of SLs in 2008, there has been much progress in the SL research field. In particular, a number of breakthroughs have been achieved in our understanding of SL biosynthesis, transport and perception. The discovery of the hormonal function of SL was quite valuable not only as the identification of a new class of plant hormones, but also as the discovery of the long-sought-after SL biosynthetic and response mutants. These mutants in several plant species provided us the genetic resources to address fundamental questions regarding SL biosynthesis and perception. Such mutants were further characterized later, and biochemical analyses of these genetically identified factors have uncovered the outline of SL biosynthesis and perception so far. Moreover, new genes involved in SL transport have been discovered through reverse genetic analyses. In this review, we summarize recent advances in SL research with a focus on biosynthesis, transport and perception.},
}
@article {pmid33118170,
year = {2020},
author = {Marqués-Gálvez, JE and Miyauchi, S and Paolocci, F and Navarro-Ródenas, A and Arenas, F and Pérez-Gilabert, M and Morin, E and Auer, L and Barry, KW and Kuo, A and Grigoriev, IV and Martin, FM and Kohler, A and Morte, A},
title = {Desert truffle genomes reveal their reproductive modes and new insights into plant-fungal interaction and ectendomycorrhizal lifestyle.},
journal = {The New phytologist},
volume = {},
number = {},
pages = {},
doi = {10.1111/nph.17044},
pmid = {33118170},
issn = {1469-8137},
support = {20866/PI/18//Fundación Séneca/ ; CGL2016-78946-R//Ministerio de Economía y Competitividad/ ; CI-2016-28252//Ministerio de Economía y Competitividad/ ; DI-14-06904//Ministerio de Economía y Competitividad/ ; ANR-11-LABX-0002-01//Laboratory of Excellence ARBRE/ ; DE-AC02-05CH11231//DOE - Joint Genome Institute/ ; },
abstract = {Desert truffles are edible hypogeous fungi forming ectendomycorrhizal symbiosis with plants of Cistaceae family. Knowledge about the reproductive modes of these fungi and the molecular mechanisms driving the ectendomycorrhizal interaction is lacking. Genomes of the highly appreciated edible desert truffles Terfezia claveryi Chatin and Tirmania nivea Trappe have been sequenced and compared with other Pezizomycetes. Transcriptomes of T. claveryi × Helianthemum almeriense mycorrhiza from well-watered and drought-stressed plants, when intracellular colonizations is promoted, were investigated. We have identified the fungal genes related to sexual reproduction in desert truffles and desert-truffles-specific genomic and secretomic features with respect to other Pezizomycetes, such as the expansion of a large set of gene families with unknown Pfam domains and a number of species or desert-truffle-specific small secreted proteins differentially regulated in symbiosis. A core set of plant genes, including carbohydrate, lipid-metabolism, and defence-related genes, differentially expressed in mycorrhiza under both conditions was found. Our results highlight the singularities of desert truffles with respect to other mycorrhizal fungi while providing a first glimpse on plant and fungal determinants involved in ecto to endo symbiotic switch that occurs in desert truffle under dry conditions.},
}
@article {pmid33117302,
year = {2020},
author = {Sun, Y and Jiang, L and Gong, S and Guo, M and Yuan, X and Zhou, G and Lei, X and Zhang, Y and Yuan, T and Lian, J and Qian, P and Huang, H},
title = {Impact of Ocean Warming and Acidification on Symbiosis Establishment and Gene Expression Profiles in Recruits of Reef Coral Acropora intermedia.},
journal = {Frontiers in microbiology},
volume = {11},
number = {},
pages = {532447},
pmid = {33117302},
issn = {1664-302X},
abstract = {The onset of symbiosis and the early development of most broadcast spawning corals play pivotal roles in recruitment success, yet these critical early stages are threatened by multiple stressors. However, molecular mechanisms governing these critical processes under ocean warming and acidification are still poorly understood. The present study investigated the interactive impact of elevated temperature (∼28.0°C and ∼30.5°C) and partial pressure of carbon dioxide (pCO2) (∼600 and ∼1,200 μatm) on early development and the gene expression patterns in juvenile Acropora intermedia over 33 days. The results showed that coral survival was >89% and was unaffected by high temperature, pCO2, or the combined treatment. Notably, high temperature completely arrested successful symbiosis establishment and the budding process, whereas acidification had a negligible effect. Moreover, there was a positive exponential relationship between symbiosis establishment and budding rates (y = 0.0004e6.43x, R = 0.72, P < 0.0001), which indicated the importance of symbiosis in fueling asexual budding. Compared with corals at the control temperature (28°C), those under elevated temperature preferentially harbored Durusdinium spp., despite unsuccessful symbiosis establishment. In addition, compared to the control, 351 and 153 differentially expressed genes were detected in the symbiont and coral host in response to experimental conditions, respectively. In coral host, some genes involved in nutrient transportation and tissue fluorescence were affected by high temperature. In the symbionts, a suite of genes related to cell growth, ribosomal proteins, photosynthesis, and energy production was downregulated under high temperatures, which may have severely hampered successful cell proliferation of the endosymbionts and explains the failure of symbiosis establishment. Therefore, our results suggest that the responses of symbionts to future ocean conditions could play a vital role in shaping successful symbiosis in juvenile coral.},
}
@article {pmid33116335,
year = {2020},
author = {Mayers, CG and Harrington, TC and Masuya, H and Jordal, BH and McNew, DL and Shih, HH and Roets, F and Kietzka, GJ},
title = {Patterns of coevolution between ambrosia beetle mycangia and the Ceratocystidaceae, with five new fungal genera and seven new species.},
journal = {Persoonia},
volume = {44},
number = {},
pages = {41-66},
pmid = {33116335},
issn = {0031-5850},
abstract = {Ambrosia beetles farm specialised fungi in sapwood tunnels and use pocket-like organs called mycangia to carry propagules of the fungal cultivars. Ambrosia fungi selectively grow in mycangia, which is central to the symbiosis, but the history of coevolution between fungal cultivars and mycangia is poorly understood. The fungal family Ceratocystidaceae previously included three ambrosial genera (Ambrosiella, Meredithiella, and Phialophoropsis), each farmed by one of three distantly related tribes of ambrosia beetles with unique and relatively large mycangium types. Studies on the phylogenetic relationships and evolutionary histories of these three genera were expanded with the previously unstudied ambrosia fungi associated with a fourth mycangium type, that of the tribe Scolytoplatypodini. Using ITS rDNA barcoding and a concatenated dataset of six loci (28S rDNA, 18S rDNA, tef1-α, tub, mcm7, and rpl1), a comprehensive phylogeny of the family Ceratocystidaceae was developed, including Inodoromyces interjectus gen. & sp. nov., a non-ambrosial species that is closely related to the family. Three minor morphological variants of the pronotal disk mycangium of the Scolytoplatypodini were associated with ambrosia fungi in three respective clades of Ceratocystidaceae: Wolfgangiella gen. nov., Toshionella gen. nov., and Ambrosiella remansi sp. nov. Closely-related species that are not symbionts of ambrosia beetles are accommodated by Catunica adiposa gen. & comb. nov. and Solaloca norvegica gen. & comb. nov. The divergent morphology of the ambrosial genera and their phylogenetic placement among non-ambrosial genera suggest three domestication events in the Ceratocystidaceae. Estimated divergence dates for the ambrosia fungi and mycangia suggest that Scolytoplatypodini mycangia may have been the first to acquire Ceratocystidaceae symbionts and other ambrosial fungal genera emerged shortly after the evolution of new mycangium types. There is no evidence of reversion to a non-ambrosial lifestyle in the mycangial symbionts.},
}
@article {pmid33115970,
year = {2020},
author = {Jadhav, S and Sanagar, S and Shaha, J and Kutty, J and Jadhav, M},
title = {A Bronchial Lipoma: Occurrence at an Unusual Site and Its Successful Bronchoscopic Resection with an Electrosurgical Snare.},
journal = {The Korean journal of thoracic and cardiovascular surgery},
volume = {53},
number = {6},
pages = {400-402},
pmid = {33115970},
issn = {2233-601X},
abstract = {Primary tracheobronchial lipoma is an extremely rare entity, the diagnosis of which is often missed initially. Cases are generally diagnosed late after initial treatment for asthma and bronchitis. We report a case of a 42-year-old man with a left main bronchus lipoma that caused near-total obstruction. The lipoma was treated by bronchoscopic resection with an electrosurgical snare and cryoablation.},
}
@article {pmid33115723,
year = {2020},
author = {Tidjani Alou, M and Naud, S and Khelaifia, S and Bonnet, M and Lagier, JC and Raoult, D},
title = {State of the Art in the Culture of the Human Microbiota: New Interests and Strategies.},
journal = {Clinical microbiology reviews},
volume = {34},
number = {1},
pages = {},
pmid = {33115723},
issn = {1098-6618},
abstract = {SUMMARYThe last 5 years have seen a turning point in the study of the gut microbiota with a rebirth of culture-dependent approaches to study the gut microbiota. High-throughput methods have been developed to study bacterial diversity with culture conditions aimed at mimicking the gut environment by using rich media such as YCFA (yeast extract, casein hydrolysate, fatty acids) and Gifu anaerobic medium in an anaerobic workstation, as well as media enriched with rumen and blood and coculture, to mimic the symbiosis of the gut microbiota. Other culture conditions target phenotypic and metabolic features of bacterial species to facilitate their isolation. Preexisting technologies such as next-generation sequencing and flow cytometry have also been utilized to develop innovative methods to isolate previously uncultured bacteria or explore viability in samples of interest. These techniques have been applied to isolate CPR (Candidate Phyla Radiation) among other, more classic approaches. Methanogenic archaeal and fungal cultures present different challenges than bacterial cultures. Efforts to improve the available systems to grow archaea have been successful through coculture systems. For fungi that are more easily isolated from the human microbiota, the challenge resides in the identification of the isolates, which has been approached by applying matrix-assisted laser desorption ionization-time of flight mass spectrometry technology to fungi. Bacteriotherapy represents a nonnegligible avenue in the future of medicine to correct dysbiosis and improve health or response to therapy. Although great strides have been achieved in the last 5 years, efforts in bacterial culture need to be sustained to continue deciphering the dark matter of metagenomics, particularly CPR, and extend these methods to archaea and fungi.},
}
@article {pmid33106084,
year = {2020},
author = {Harris, JM and Balint-Kurti, P and Bede, JC and Day, B and Gold, S and Goss, EM and Grenville-Briggs, LJ and Jones, KM and Wang, A and Wang, Y and Mitra, RM and Sohn, KH and Alvarez, ME},
title = {What are the Top 10 Unanswered Questions in Molecular Plant-Microbe Interactions?.},
journal = {Molecular plant-microbe interactions : MPMI},
volume = {33},
number = {12},
pages = {1354-1365},
doi = {10.1094/MPMI-08-20-0229-CR},
pmid = {33106084},
issn = {0894-0282},
abstract = {This article is part of the Top 10 Unanswered Questions in MPMI invited review series.The past few decades have seen major discoveries in the field of molecular plant-microbe interactions. As the result of technological and intellectual advances, we are now able to answer questions at a level of mechanistic detail that we could not have imagined possible 20 years ago. The MPMI Editorial Board felt it was time to take stock and reassess. What big questions remain unanswered? We knew that to identify the fundamental, overarching questions that drive our research, we needed to do this as a community. To reach a diverse audience of people with different backgrounds and perspectives, working in different areas of plant-microbe interactions, we queried the more than 1,400 participants at the 2019 International Congress on Molecular Plant-Microbe Interactions meeting in Glasgow. This group effort resulted in a list of ten, broad-reaching, fundamental questions that influence and inform our research. Here, we introduce these Top 10 unanswered questions, giving context and a brief description of the issues. Each of these questions will be the subject of a detailed review in the coming months. We hope that this process of reflecting on what is known and unknown and identifying the themes that underlie our research will provide a framework to use going forward, giving newcomers a sense of the mystery of the big questions and inspiring new avenues and novel insights.[Formula: see text] Copyright © 2020 The Author(s). This is an open access article distributed under the CC BY 4.0 International license.},
}
@article {pmid33105830,
year = {2020},
author = {Shahbazi, R and Yasavoli-Sharahi, H and Alsadi, N and Ismail, N and Matar, C},
title = {Probiotics in Treatment of Viral Respiratory Infections and Neuroinflammatory Disorders.},
journal = {Molecules (Basel, Switzerland)},
volume = {25},
number = {21},
pages = {},
pmid = {33105830},
issn = {1420-3049},
mesh = {Betacoronavirus/drug effects/pathogenicity/physiology ; Brain/immunology ; COVID-19 ; Coronavirus Infections/immunology/microbiology/*therapy/virology ; Gastrointestinal Microbiome/immunology ; Gastrointestinal Tract/immunology/microbiology ; Humans ; Immunomodulation ; Influenza, Human/immunology/microbiology/*therapy/virology ; Lung/immunology ; Mental Disorders/immunology/microbiology/*therapy ; Microbial Consortia/immunology ; Multiple Sclerosis/immunology/microbiology/*therapy ; Orthomyxoviridae/drug effects/pathogenicity/physiology ; Pandemics ; Pneumonia, Viral/immunology/microbiology/*therapy/virology ; Probiotics/*therapeutic use ; Respiratory Tract Infections/immunology/microbiology/*therapy ; SARS-CoV-2 ; Symbiosis/immunology ; },
abstract = {Inflammation is a biological response to the activation of the immune system by various infectious or non-infectious agents, which may lead to tissue damage and various diseases. Gut commensal bacteria maintain a symbiotic relationship with the host and display a critical function in the homeostasis of the host immune system. Disturbance to the gut microbiota leads to immune dysfunction both locally and at distant sites, which causes inflammatory conditions not only in the intestine but also in the other organs such as lungs and brain, and may induce a disease state. Probiotics are well known to reinforce immunity and counteract inflammation by restoring symbiosis within the gut microbiota. As a result, probiotics protect against various diseases, including respiratory infections and neuroinflammatory disorders. A growing body of research supports the beneficial role of probiotics in lung and mental health through modulating the gut-lung and gut-brain axes. In the current paper, we discuss the potential role of probiotics in the treatment of viral respiratory infections, including the COVID-19 disease, as major public health crisis in 2020, and influenza virus infection, as well as treatment of neurological disorders like multiple sclerosis and other mental illnesses.},
}
@article {pmid33105490,
year = {2020},
author = {Basyal, B and Emery, SM},
title = {An arbuscular mycorrhizal fungus alters switchgrass growth, root architecture, and cell wall chemistry across a soil moisture gradient.},
journal = {Mycorrhiza},
volume = {},
number = {},
pages = {},
doi = {10.1007/s00572-020-00992-6},
pmid = {33105490},
issn = {1432-1890},
abstract = {The abiotic environment can dictate the relative costs and benefits of plant-arbuscular mycorrhizal fungi (AMF) symbioses. While the effects of varying light or soil nutrient conditions are well studied, outcomes of plant-AMF interactions along soil moisture gradients are not fully understood. It is predicted that mycorrhizal associations may become parasitic in extreme soil moisture conditions. Under low soil moisture stress, costs of maintaining a mycorrhizal symbiont may outweigh benefits for the host plant, whereas under high soil moisture stress, the host plant may not need the symbiont. In a factorial growth chamber study, we investigated the effects of a plant-arbuscular mycorrhizal fungus symbiosis along a soil moisture gradient on growth, cell wall chemistry, and root architecture of a biofuel crop, Panicum virgatum (switchgrass). Regardless of soil moisture conditions, we found an increase in the number of tillers, number of leaves, root biomass, and amount of cellulose and hemicellulose in response to root colonization by the arbuscular mycorrhizal fungus. The fungus also increased aboveground biomass and changed several root architectural traits, but only under low soil moisture conditions, indicating a reduction in benefits of the mycorrhizal association under high soil moisture. Results from this study indicate that an arbuscular mycorrhizal fungus can increase some key measures of plant growth and cell wall chemistry regardless of soil moisture conditions but is most beneficial in low soil moisture conditions.},
}
@article {pmid33103993,
year = {2020},
author = {Lari, S and Medithi, S and Kasa, YD and Pandiyan, A and Jonnalagadda, P},
title = {Pesticide handling practices and self-reported morbidity symptoms among farmers.},
journal = {Archives of environmental & occupational health},
volume = {},
number = {},
pages = {1-11},
doi = {10.1080/19338244.2020.1828245},
pmid = {33103993},
issn = {2154-4700},
abstract = {Amid growing concern about the adverse effects of pesticides, a questionnaire-based cross-sectional study was conducted to evaluate farmers' knowledge on pesticides handling. Results of in-depth surveys (n = 217) with field observations revealed that participants had a mean 18 years of farming experience and knapsack-sprays were used for spraying. About 99% were not using any personal-protective-equipments during mixing, loading, application operations. Over 80% reentered the treated farms within two-days of application without following safety protocols and 39% admitted unsafe disposal of empty containers of pesticides. Statistical-analysis revealed a significant association between participant's pesticide handling practices and self-reported morbidity symptoms (p < 0.05). Despite awareness of toxicity, participants were mishandling the pesticides. Training on safe handling practices and incentives in form of personal-protective-equipments could be productive to ensure safety at work.},
}
@article {pmid33102664,
year = {2020},
author = {Kataev, VY and Sleptsov, II and Martynov, AA and Aduchiev, BK and Khlopko, YA and Miroshnikov, SA and Cherkasov, SV and Plotnikov, AO},
title = {Data on rumen and faeces microbiota profiles of Yakutian and Kalmyk cattle revealed by high-throughput sequencing of 16S rRNA gene amplicons.},
journal = {Data in brief},
volume = {33},
number = {},
pages = {106407},
pmid = {33102664},
issn = {2352-3409},
abstract = {It is known that the rumen microbiome directly or indirectly contributes to animal production, and may be a prospective target for mitigation of greenhouse gas emissions [1]. At the same time, feed types and components of diet can influence the composition of the rumen microbiome [2,3]. Fluctuations in the composition of the digestive tract microbiota can alter the development, health, and productivity of cattle [4]. Many studies of cattle microbiomes have focussed on the rumen microbiota, whereas the faecal microbiota has received less attention [5], [6], [7]. Therefore, the features of the faecal and the ruminal microbiomes in different cattle breeds are yet to be studied. Here, we provided 16S rRNA gene amplicon data of the ruminal and the faecal microbiomes from Yakutian and Kalmyk cattle living in the Republic of Sakha, Yakutia, Russia. Total DNA was extracted from 13 faecal and 13 ruminal samples, and DNA libraries were prepared and sequenced on an Illumina MiSeq platform. Paired-end raw reads were processed, and final operational taxonomic units (OTUs) were assigned to the respective prokaryotic taxa using the RDP (Ribosomal Database Project) database. Analysis of the microbiome composition at the phylum level revealed very similar faecal microbiota between the introduced Kalmyk breed and the indigenous Yakutian breed, whereas the ruminal microbiomes of these breeds differed substantially in terms of relative abundance of some prokaryotic phyla. We believe that the data obtained may provide new insights into the dynamics of the ruminal and the faecal microbiota of cattle as well as disclose breed-specific features of ruminal microbiomes. Besides, these data will contribute to our understanding of the ruminal microbiome structure and function, and might be useful for the management of cattle feeding and ruminal methane production.},
}
@article {pmid33101237,
year = {2020},
author = {Grubbs, KJ and Surup, F and Biedermann, PHW and McDonald, BR and Klassen, JL and Carlson, CM and Clardy, J and Currie, CR},
title = {Cycloheximide-Producing Streptomyces Associated With Xyleborinus saxesenii and Xyleborus affinis Fungus-Farming Ambrosia Beetles.},
journal = {Frontiers in microbiology},
volume = {11},
number = {},
pages = {562140},
pmid = {33101237},
issn = {1664-302X},
support = {T32 GM007215/GM/NIGMS NIH HHS/United States ; },
abstract = {Symbiotic microbes help a myriad of insects acquire nutrients. Recent work suggests that insects also frequently associate with actinobacterial symbionts that produce molecules to help defend against parasites and predators. Here we explore a potential association between Actinobacteria and two species of fungus-farming ambrosia beetles, Xyleborinus saxesenii and Xyleborus affinis. We isolated and identified actinobacterial and fungal symbionts from laboratory reared nests, and characterized small molecules produced by the putative actinobacterial symbionts. One 16S rRNA phylotype of Streptomyces (XylebKG-1) was abundantly and consistently isolated from the galleries and adults of X. saxesenii and X. affinis nests. In addition to Raffaelea sulphurea, the symbiont that X. saxesenii cultivates, we also repeatedly isolated a strain of Nectria sp. that is an antagonist of this mutualism. Inhibition bioassays between Streptomyces griseus XylebKG-1 and the fungal symbionts from X. saxesenii revealed strong inhibitory activity of the actinobacterium toward the fungal antagonist Nectria sp. but not the fungal mutualist R. sulphurea. Bioassay guided HPLC fractionation of S. griseus XylebKG-1 culture extracts, followed by NMR and mass spectrometry, identified cycloheximide as the compound responsible for the observed growth inhibition. A biosynthetic gene cluster putatively encoding cycloheximide was also identified in S. griseus XylebKG-1. The consistent isolation of a single 16S phylotype of Streptomyces from two species of ambrosia beetles, and our finding that a representative isolate of this phylotype produces cycloheximide, which inhibits a parasite of the system but not the cultivated fungus, suggests that these actinobacteria may play defensive roles within these systems.},
}
@article {pmid33101225,
year = {2020},
author = {Blanton, AG and Peterson, BF},
title = {Symbiont-Mediated Insecticide Detoxification as an Emerging Problem in Insect Pests.},
journal = {Frontiers in microbiology},
volume = {11},
number = {},
pages = {547108},
pmid = {33101225},
issn = {1664-302X},
abstract = {Pesticide use is prevalent with applications from the backyard gardener to large-scale agriculture and combatting pests in homes and industrial settings. Alongside the need to control unwanted pests comes the selective pressure generated by sustained pesticide use has become a concern leading to environmental contamination, pest resistance, and, thus, reduced pesticide efficacy. Despite efforts to improve the environmental impact and reduce off-target effects, chemical pesticides are relied on and control failures are costly. Though pesticide resistance mechanisms vary, one pattern that has recently emerged is symbiont-mediated detoxification within insect pests. The localization within the insect host, the identity of the symbiotic partner, and the stability of the associations across different systems vary. The diversity of insects and ecological settings linked to this phenomenon are broad. In this mini-review, we summarize the recent trend of insecticide detoxification modulated by symbiotic associations between bacteria and insects, as well as highlight the implications for pesticide development, pest management strategies, and pesticide bioremediation.},
}
@article {pmid33099700,
year = {2020},
author = {Matsuda, Y and Yamaguchi, Y and Matsuo, N and Uesugi, T and Ito, J and Yagame, T and Figura, T and Selosse, MA and Hashimoto, Y},
title = {Communities of mycorrhizal fungi in different trophic types of Asiatic Pyrola japonica sensu lato (Ericaceae).},
journal = {Journal of plant research},
volume = {133},
number = {6},
pages = {841-853},
doi = {10.1007/s10265-020-01233-9},
pmid = {33099700},
issn = {1618-0860},
support = {25304026//KAKENHI/ ; },
mesh = {DNA Barcoding, Taxonomic ; Heterotrophic Processes ; Japan ; *Mycorrhizae ; Phylogeny ; Plant Leaves ; Pyrola/*microbiology ; Rhizome ; Symbiosis ; },
abstract = {Mixotrophic plants obtain carbon by their own photosynthetic activity and from their root-associated mycorrhizal fungi. Mixotrophy is deemed a pre-adaptation for evolution of mycoheterotrophic nutrition, where plants fully depend on fungi and lose their photosynthetic activity. The aim of this study was to clarify mycorrhizal dependency and heterotrophy level in various phenotypes of mixotrophic Pyrola japonica (Ericaceae), encompassing green individuals, rare achlorophyllous variants (albinos) and a form with minute leaves, P. japonica f. subaphylla. These three phenotypes were collected in two Japanese forests. Phylogenetic analysis of both plants and mycorrhizal fungi was conducted based on DNA barcoding. Enrichment in 13C among organs (leaves, stems and roots) of the phenotypes with reference plants and fungal fruitbodies were compared by measuring stable carbon isotopic ratio. All plants were placed in the same clade, with f. subaphylla as a separate subclade. Leaf 13C abundances of albinos were congruent with a fully mycoheterotrophic nutrition, suggesting that green P. japonica leaves are 36.8% heterotrophic, while rhizomes are 74.0% heterotrophic. There were no significant differences in δ13C values among organs in both albino P. japonica and P. japonica f. subaphylla, suggesting full and high mycoheterotrophic nutrition, respectively. Among 55 molecular operational taxonomic units (OTUs) detected as symbionts, the genus Russula was the most abundant in each phenotype and its dominance was significantly higher in albino P. japonica and P. japonica f. subaphylla. Russula spp. detected in P. japonica f. subaphylla showed higher dissimilarity with other phenotypes. These results suggest that P. japonica sensu lato is prone to evolve mycoheterotrophic variants, in a process that changes its mycorrhizal preferences, especially towards the genus Russula for which this species has a marked preference.},
}
@article {pmid33099003,
year = {2020},
author = {Aschner, M and Nguyen, TT and Sinitskii, AI and Santamaría, A and Bornhorst, J and Ajsuvakova, OP and da Rocha, JBT and Skalny, AV and Tinkov, AA},
title = {Isolevuglandins (isoLGs) as toxic lipid peroxidation byproducts and their pathogenetic role in human diseases.},
journal = {Free radical biology & medicine},
volume = {},
number = {},
pages = {},
doi = {10.1016/j.freeradbiomed.2020.10.024},
pmid = {33099003},
issn = {1873-4596},
abstract = {Lipid peroxidation results in generation of a variety of lipid hydroperoxides and other highly reactive species that covalently modify proteins, nucleic acids, and other lipids, thus resulting in lipotoxicity. Although biological relevance of 4-hydroxynonenal (4-HNE) and malondialdehyde (MDA) is well studied, the existing data on the role of isolevuglandins (isoLGs) in pathology are insufficient. Therefore, the objective of the present study was to review the existing data on biological effects of isoLG and isoLG adducts and their role in multiple diseases. Sixty four highly reactive levuglandin-like γ-ketoaldehyde (γ-KA, or isoketals, IsoK, or isolevuglandins, IsoLG) regio- and stereo-isomers are formed as products of arachidonic acid oxidation. IsoLGs react covalently with lysyl residues of proteins to form a stable adduct and intramolecular aminal, bispyrrole, and trispyrrole cross-links. Phosphatidylethanolamine was also shown to be the target for isoLG binding as compared to proteins and DNA. Free IsoLGs are not detectable in vivo, although isolevuglandin adduction to amino acid residues of particular proteins may be evaluated with liquid chromatography-tandem mass spectrometry. Adducts formed were shown to play a significant role in the development and maintenance of oxidative stress, endoplasmic reticulum stress, mitochondrial dysfunction, and inflammation. These, and more specific molecular pathways, link isoLG and isoLG-adduct formation to develop a variety of pathologies, including cardiovascular diseases (atherosclerosis, hypertension, heart failure), obesity and diabetes, cancer, neurodegeneration, eye diseases (retinal degeneration and glaucoma), as well as ageing. Hypothetically, isoLGs and isoLG adduct formation may be considered as the potential target for treatment of oxidative stress-related diseases.},
}
@article {pmid33098658,
year = {2020},
author = {Palmer, TM and Riginos, C and Milligan, PD and Hays, BR and Pietrek, AG and Maiyo, NJ and Mutisya, S and Gituku, B and Musila, S and Carpenter, S and Goheen, JR},
title = {Frenemy at the gate: Invasion by Pheidole megacephala facilitates a competitively subordinate plant ant in Kenya.},
journal = {Ecology},
volume = {},
number = {},
pages = {e03230},
doi = {10.1002/ecy.3230},
pmid = {33098658},
issn = {1939-9170},
support = {NSF DEB 1556905//National Science Foundation/ ; },
abstract = {Biological invasions can lead to the reassembly of communities and understanding and predicting the impacts of exotic species on community structure and functioning are a key challenge in ecology. We investigated the impact of a predatory species of invasive ant, Pheidole megacephala, on the structure and function of a foundational mutualism between Acacia drepanolobium and its associated acacia-ant community in an East African savanna. Invasion by P. megacephala was associated with the extirpation of three extrafloral nectar-dependent Crematogaster acacia ant species and strong increases in the abundance of a competitively subordinate and locally rare acacia ant species, Tetraponera penzigi, which does not depend on host plant nectar. Using a combination of long-term monitoring of invasion dynamics, observations and experiments, we demonstrate that P. megacephala directly and indirectly facilitates T. penzigi by reducing the abundance of T. penzigi's competitors (Crematogaster spp.), imposing recruitment limitation on these competitors, and generating a landscape of low-reward host plants that favor colonization and establishment by the strongly dispersing T. penzigi. Seasonal variation in use of host plants by P. megacephala may further increase the persistence of T. penzigi colonies in invaded habitat. The persistence of the T. penzigi-A. drepanolobium symbiosis in invaded areas afforded host plants some protection against herbivory by elephants (Loxodonta africana), a key browser that reduces tree cover. However, elephant damage on T. penzigi-occupied trees was higher in invaded than in uninvaded areas, likely owing to reduced T. penzigi colony size in invaded habitats. Our results reveal the mechanisms underlying the disruption of this mutualism and suggest that P. megacephala invasion may drive long-term declines in tree cover, despite the partial persistence of the ant-acacia symbiosis in invaded areas.},
}
@article {pmid33097853,
year = {2020},
author = {Jackrel, SL and Yang, JW and Schmidt, KC and Denef, VJ},
title = {Host specificity of microbiome assembly and its fitness effects in phytoplankton.},
journal = {The ISME journal},
volume = {},
number = {},
pages = {},
doi = {10.1038/s41396-020-00812-x},
pmid = {33097853},
issn = {1751-7370},
support = {Dow Sustainability Fellow//Dow Chemical Company (Dow)/ ; NSF-EAGER # 1737680//National Science Foundation (NSF)/ ; EFRI-PRSB #1332342//National Science Foundation (NSF)/ ; 1332342//NSF | BIO | Division of Emerging Frontiers (EF)/ ; },
abstract = {Insights into symbiosis between eukaryotic hosts and their microbiomes have shifted paradigms on what determines host fitness, ecology, and behavior. Questions remain regarding the roles of host versus environment in shaping microbiomes, and how microbiome composition affects host fitness. Using a model system in ecology, phytoplankton, we tested whether microbiomes are host-specific, confer fitness benefits that are host-specific, and remain conserved in time in their composition and fitness effects. We used an experimental approach in which hosts were cleaned of bacteria and then exposed to bacterial communities from natural environments to permit recruitment of microbiomes. We found that phytoplankton microbiomes consisted of a subset of taxa recruited from these natural environments. Microbiome recruitment was host-specific, with host species explaining more variation in microbiome composition than environment. While microbiome composition shifted and then stabilized over time, host specificity remained for dozens of generations. Microbiomes increased host fitness, but these fitness effects were host-specific for only two of the five species. The shifts in microbiome composition over time amplified fitness benefits to the hosts. Overall, this work solidifies the importance of host factors in shaping microbiomes and elucidates the temporal dynamics of microbiome compositional and fitness effects.},
}
@article {pmid33096259,
year = {2020},
author = {Li, M and Liu, H and Guo, Y and Chen, F and Zi, X and Fan, R and Li, H and Cai, Y and He, C and Lu, Z and Zhao, X},
title = {Single symbiotic cell transcriptome sequencing of coral.},
journal = {Genomics},
volume = {112},
number = {6},
pages = {5305-5312},
doi = {10.1016/j.ygeno.2020.10.019},
pmid = {33096259},
issn = {1089-8646},
abstract = {Zooxanthellae and coral can form an intracellular symbiotic system. Yet, little is known about the molecular mechanism underlying this symbiosis. In this study, we characterized the symbiosis based on analyses of gene expression at the single-cell level. Among 9110 single coral cells, we identified 4871 symbiotic cells based on the detection of both coral and zooxanthellae gene transcripts within a single cell. Using the bioinformatics tool Seurat, symbiotic cells were further clustered into five groups, 52 genes exhibited differential expression between groups. We proposed an index called the "symbiosis index", to indicate the degree of gene expression of both species in a single symbiotic cell. Interestingly, the index differed distinctly among the five groups. The symbiosis index was highly correlated with the expression of the coral gene gfas1.m1.6761 (ANKRD40), which encodes ankyrin repeat domain-containing protein 40 and is involved in DNA replication (r = 0.76). Two metabolism-related genes, DAGLA and betaGlu, were highly expressed in cells with a high symbiosis index. Four zooxanthellae genes, PRPF19, ATRN, aAA-ATPases and AK812-SmicGene44833, exhibited substantial changes in expression levels when zooxanthellae lived within coral. A trajectory analysis suggested that cells with a higher symbiosis index may be derived from those with a lower index during coral colony development. Taken together, our results provide evidence for zooxanthellae residing within coral, forming a symbiotic system. The symbiosis index is an effective indicator of different cell groups, with lineage relationships among groups. Additionally, we identified specific genes that exhibit expression changes in the symbiotic system.},
}
@article {pmid33093662,
year = {2020},
author = {Morais, LH and Schreiber, HL and Mazmanian, SK},
title = {The gut microbiota-brain axis in behaviour and brain disorders.},
journal = {Nature reviews. Microbiology},
volume = {},
number = {},
pages = {},
doi = {10.1038/s41579-020-00460-0},
pmid = {33093662},
issn = {1740-1534},
abstract = {In a striking display of trans-kingdom symbiosis, gut bacteria cooperate with their animal hosts to regulate the development and function of the immune, metabolic and nervous systems through dynamic bidirectional communication along the 'gut-brain axis'. These processes may affect human health, as certain animal behaviours appear to correlate with the composition of gut bacteria, and disruptions in microbial communities have been implicated in several neurological disorders. Most insights about host-microbiota interactions come from animal models, which represent crucial tools for studying the various pathways linking the gut and the brain. However, there are complexities and manifest limitations inherent in translating complex human disease to reductionist animal models. In this Review, we discuss emerging and exciting evidence of intricate and crucial connections between the gut microbiota and the brain involving multiple biological systems, and possible contributions by the gut microbiota to neurological disorders. Continued advances from this frontier of biomedicine may lead to tangible impacts on human health.},
}
@article {pmid33093112,
year = {2020},
author = {Batstone, RT and O'Brien, AM and Harrison, TL and Frederickson, ME},
title = {Experimental evolution makes microbes more cooperative with their local host genotype.},
journal = {Science (New York, N.Y.)},
volume = {370},
number = {6515},
pages = {476-478},
doi = {10.1126/science.abb7222},
pmid = {33093112},
issn = {1095-9203},
mesh = {*Adaptation, Biological ; Host Microbial Interactions/*genetics ; Medicago truncatula/*genetics/*microbiology ; Microbiota/*physiology ; Sinorhizobium meliloti/*physiology ; Symbiosis ; },
abstract = {Advances in microbiome science require a better understanding of how beneficial microbes adapt to hosts. We tested whether hosts select for more-cooperative microbial strains with a year-long evolution experiment and a cross-inoculation experiment designed to explore how nitrogen-fixing bacteria (rhizobia) adapt to legumes. We paired the bacterium Ensifer meliloti with one of five Medicago truncatula genotypes that vary in how strongly they "choose" bacterial symbionts. Independent of host choice, E. meliloti rapidly adapted to its local host genotype, and derived microbes were more beneficial when they shared evolutionary history with their host. This local adaptation was mostly limited to the symbiosis plasmids, with mutations in putative signaling genes. Thus, cooperation depends on the match between partner genotypes and increases as bacteria adapt to their local host.},
}
@article {pmid33093110,
year = {2020},
author = {Bergstrom, K and Shan, X and Casero, D and Batushansky, A and Lagishetty, V and Jacobs, JP and Hoover, C and Kondo, Y and Shao, B and Gao, L and Zandberg, W and Noyovitz, B and McDaniel, JM and Gibson, DL and Pakpour, S and Kazemian, N and McGee, S and Houchen, CW and Rao, CV and Griffin, TM and Sonnenburg, JL and McEver, RP and Braun, J and Xia, L},
title = {Proximal colon-derived O-glycosylated mucus encapsulates and modulates the microbiota.},
journal = {Science (New York, N.Y.)},
volume = {370},
number = {6515},
pages = {467-472},
doi = {10.1126/science.aay7367},
pmid = {33093110},
issn = {1095-9203},
support = {R01 DK085691/DK/NIDDK NIH HHS/United States ; P20 GM103441/GM/NIGMS NIH HHS/United States ; },
mesh = {Animals ; Colon/*metabolism/*microbiology ; Feces/microbiology ; *Gastrointestinal Microbiome ; Glycosylation ; Mice ; Mice, Knockout ; Mucin-2/genetics/*metabolism ; Mucus/*metabolism ; Transcription, Genetic ; },
abstract = {Colon mucus segregates the intestinal microbiota from host tissues, but how it organizes to function throughout the colon is unclear. In mice, we found that colon mucus consists of two distinct O-glycosylated entities of Muc2: a major form produced by the proximal colon, which encapsulates the fecal material including the microbiota, and a minor form derived from the distal colon, which adheres to the major form. The microbiota directs its own encapsulation by inducing Muc2 production from proximal colon goblet cells. In turn, O-glycans on proximal colon-derived Muc2 modulate the structure and function of the microbiota as well as transcription in the colon mucosa. Our work shows how proximal colon control of mucin production is an important element in the regulation of host-microbiota symbiosis.},
}
@article {pmid33092221,
year = {2020},
author = {Marczak, M and Wójcik, M and Żebracki, K and Turska-Szewczuk, A and Talarek, K and Nowak, D and Wawiórka, L and Sieńczyk, M and Łupicka-Słowik, A and Bobrek, K and Romańczuk, M and Koper, P and Mazur, A},
title = {PssJ Is a Terminal Galactosyltransferase Involved in the Assembly of the Exopolysaccharide Subunit in Rhizobium Leguminosarum bv. Trifolii.},
journal = {International journal of molecular sciences},
volume = {21},
number = {20},
pages = {},
pmid = {33092221},
issn = {1422-0067},
support = {2017/27/B/NZ9/01849//Narodowe Centrum Nauki/ ; Statute Funds 8201003902//Wroclaw University of Science and Technology/ ; },
abstract = {Rhizobium leguminosarum bv. trifolii produces exopolysaccharide (EPS) composed of glucose, glucuronic acid, and galactose residues at a molar ratio 5:2:1. A majority of genes involved in the synthesis, modification, and export of exopolysaccharide are located in the chromosomal Pss-I region. In the present study, a ΔpssJ deletion mutant was constructed and shown to produce EPS lacking terminal galactose in the side chain of the octasaccharide subunit. The lack of galactose did not block EPS subunit translocation and polymerization. The in trans delivery of the pssJ gene restored the production of galactose-containing exopolysaccharide. The mutant was compromised in several physiological traits, e.g., motility and biofilm production. An impact of the pssJ mutation and changed EPS structure on the symbiotic performance was observed as improper signaling at the stage of molecular recognition, leading to formation of a significant number of non-infected empty nodules. Terminal galactosyltransferase PssJ was shown to display a structure typical for the GT-A class of glycosyltransferases and interact with other GTs and Wzx/Wzy system proteins. The latter, together with PssJ presence in soluble and membrane protein fractions indicated that the protein plays its role at the inner membrane interface and as a component of a larger complex.},
}
@article {pmid33092035,
year = {2020},
author = {Engl, T and Schmidt, THP and Kanyile, SN and Klebsch, D},
title = {Metabolic Cost of a Nutritional Symbiont Manifests in Delayed Reproduction in a Grain Pest Beetle.},
journal = {Insects},
volume = {11},
number = {10},
pages = {},
pmid = {33092035},
issn = {2075-4450},
support = {position of TE//Max-Planck-Gesellschaft/ ; },
abstract = {Animals engage in a plethora of mutualistic interactions with microorganisms that can confer various benefits to their host but can also incur context-dependent costs. The sawtoothed grain beetle Oryzaephilus surinamensis harbors nutritional, intracellular Bacteroidetes bacteria that supplement precursors for the cuticle synthesis and thereby enhance desiccation resistance of its host. Experimental elimination of the symbiont impairs cuticle formation and reduces fitness under desiccation stress but does not disrupt the host's life cycle. For this study, we first demonstrated that symbiont populations showed the strongest growth at the end of metamorphosis and then declined continuously in males, but not in females. The symbiont loss neither impacted the development time until adulthood nor adult mortality or lifespan. Furthermore, lifetime reproduction was not influenced by the symbiont presence. However, symbiotic females started to reproduce almost two weeks later than aposymbiotic ones. Thus, symbiont presence incurs a metabolic and context-dependent fitness cost to females, probably due to a nutrient allocation trade-off between symbiont growth and sexual maturation. The O. surinamensis symbiosis thereby represents an experimentally amenable system to study eco-evolutionary dynamics under variable selection pressures.},
}
@article {pmid33091033,
year = {2020},
author = {Young, BD and Serrano, XM and Rosales, SM and Miller, MW and Williams, D and Traylor-Knowles, N},
title = {Innate immune gene expression in Acropora palmata is consistent despite variance in yearly disease events.},
journal = {PloS one},
volume = {15},
number = {10},
pages = {e0228514},
pmid = {33091033},
issn = {1932-6203},
mesh = {Alveolata/*genetics ; Animals ; Anthozoa/genetics/immunology/*parasitology ; Climate Change ; Gene Expression Profiling/*veterinary ; Gene Expression Regulation ; Genotype ; *Immunity, Innate ; Protozoan Proteins/genetics ; Ribosomal Proteins/genetics ; Symbiosis ; },
abstract = {Coral disease outbreaks are expected to increase in prevalence, frequency and severity due to climate change and other anthropogenic stressors. This is especially worrying for the Caribbean branching coral Acropora palmata which has already seen an 80% decrease in cover primarily due to disease. Despite the importance of this keystone species, there has yet to be a characterization of its transcriptomic response to disease exposure. In this study we provide the first transcriptomic analysis of 12 A. palmata genotypes and their symbiont Symbiodiniaceae exposed to disease in 2016 and 2017. Year was the primary driver of gene expression variance for A. palmata and the Symbiodiniaceae. We hypothesize that lower expression of ribosomal genes in the coral, and higher expression of transmembrane ion transport genes in the Symbiodiniaceae indicate that a compensation or dysbiosis may be occurring between host and symbiont. Disease response was the second driver of gene expression variance for A. palmata and included a core set of 422 genes that were significantly differentially expressed. Of these, 2 genes (a predicted cyclin-dependent kinase 11b and aspartate 1-decarboxylase) showed negative Log2 fold changes in corals showing transmission of disease, and positive Log2 fold changes in corals showing no transmission of disease, indicating that these may be important in disease resistance. Co-expression analysis identified two modules positively correlated to disease exposure, one enriched for lipid biosynthesis genes, and the other enriched in innate immune genes. The hub gene in the immune module was identified as D-amino acid oxidase, a gene implicated in phagocytosis and microbiome homeostasis. The role of D-amino acid oxidase in coral immunity has not been characterized but could be an important enzyme for responding to disease. Our results indicate that A. palmata mounts a core immune response to disease exposure despite differences in the disease type and virulence between 2016 and 2017. These identified genes may be important for future biomarker development in this Caribbean keystone species.},
}
@article {pmid33090749,
year = {2020},
author = {Kidaj, D and Krysa, M and Susniak, K and Matys, J and Komaniecka, I and Sroka-Bartnicka, A},
title = {Biological activity of Nod factors.},
journal = {Acta biochimica Polonica},
volume = {67},
number = {4},
pages = {435-440},
doi = {10.18388/abp.2020_5353},
pmid = {33090749},
issn = {1734-154X},
abstract = {Chemically, the Nod factors (NFs) are lipochitooligosaccharides, produced mainly by bacteria of the Rhizobium genus. They are the main signaling molecules involved in the initiation of symbiosis between rhizobia and legume plants. Nod factors affect plant tissues at very low concentrations, even as low as 10-12 mol/L. They induce root hair deformation, cortical cell division, and root nodules' formation in the host plant. At the molecular level, the cytoskeleton is reorganized and expression of genes encoding proteins called nodulins is induced in response to Nod factors in the cell. Action of Nod factors is highly specific because it depends on the structure of a particular Nod factor involved, as well as the plant receptor reacting with it.},
}
@article {pmid33088201,
year = {2020},
author = {Suzuki, M and Numazaki, R and Nakagawa, T and Shibuya, N and Kaku, H},
title = {Cytoplasmic interaction of LysM receptors contributes to the formation of symbiotic receptor complex.},
journal = {Plant biotechnology (Tokyo, Japan)},
volume = {37},
number = {3},
pages = {359-362},
pmid = {33088201},
issn = {1342-4580},
abstract = {Receptor complex formation at the cell surface is a key step to initiate downstream signaling but the contribution of this process for the regulation of the direction of downstream responses is not well understood. In the plant-microbe interactions, while CERK1, an Arabidopsis LysM-RLK, mediates chitin-induced immune responses, NFR1, a Lotus homolog of CERK1, regulates the symbiotic process with rhizobial bacteria through the recognition of Nod factors. Concerning the mechanistic insight of the regulation of such apparently opposite biological responses by the structurally related RLKs, Nakagawa et al. previously showed that the addition of YAQ sequence, conserved in NFR1 and other symbiotic LysM-RLKs, to the kinase domain of CERK1 switched downstream responses from defense to symbiosis using a set of chimeric receptors, NFR1-CERK1s. These results indicated that such a subtle difference in the cytoplasmic domain of LysM-RLKs could determine the direction of host responses from defense to symbiosis. On the other hand, it is still not understood how such structural differences in the cytoplasmic domains determine the direction of host responses. We here analyzed the interaction between chimeric NFR1s and NFR5, a partner receptor of NFR1, by co-immunoprecipitation (Co-IP) of these proteins transiently expressed in Nicotiana benthamiana. These results indicated that the cytoplasmic interaction between the LysM-RLKs is important for the symbiotic receptor complex formation and the YAQ containing region of NFR1 contributes to trigger symbiotic signaling through the successful formation of NFR1/NFR5 complex.},
}
@article {pmid33087470,
year = {2020},
author = {Mason, RAB and Wall, CB and Cunning, R and Dove, S and Gates, RD},
title = {High light alongside elevated PCO2 alleviates thermal depression of photosynthesis in a hard coral (Pocillopora acuta).},
journal = {The Journal of experimental biology},
volume = {223},
number = {Pt 20},
pages = {},
doi = {10.1242/jeb.223198},
pmid = {33087470},
issn = {1477-9145},
abstract = {The absorbtion of human-emitted CO2 by the oceans (elevated PCO2) is projected to alter the physiological performance of coral reef organisms by perturbing seawater chemistry (i.e. ocean acidification). Simultaneously, greenhouse gas emissions are driving ocean warming and changes in irradiance (through turbidity and cloud cover), which have the potential to influence the effects of ocean acidification on coral reefs. Here, we explored whether physiological impacts of elevated PCO2 on a coral-algal symbiosis (Pocillopora acuta-Symbiodiniaceae) are mediated by light and/or temperature levels. In a 39 day experiment, elevated PCO2 (962 versus 431 µatm PCO2) had an interactive effect with midday light availability (400 versus 800 µmol photons m-2 s-1) and temperature (25 versus 29°C) on areal gross and net photosynthesis, for which a decline at 29°C was ameliorated under simultaneous high-PCO2 and high-light conditions. Light-enhanced dark respiration increased under elevated PCO2 and/or elevated temperature. Symbiont to host cell ratio and chlorophyll a per symbiont increased at elevated temperature, whilst symbiont areal density decreased. The ability of moderately strong light in the presence of elevated PCO2 to alleviate the temperature-induced decrease in photosynthesis suggests that higher substrate availability facilitates a greater ability for photochemical quenching, partially offsetting the impacts of high temperature on the photosynthetic apparatus. Future environmental changes that result in moderate increases in light levels could therefore assist the P. acuta holobiont to cope with the 'one-two punch' of rising temperatures in the presence of an acidifying ocean.},
}
@article {pmid33086184,
year = {2021},
author = {Tang, J and Wu, Z and Wan, L and Cai, W and Chen, S and Wang, X and Luo, J and Zhou, Z and Zhao, J and Lin, S},
title = {Differential enrichment and physiological impacts of ingested microplastics in scleractinian corals in situ.},
journal = {Journal of hazardous materials},
volume = {404},
number = {Pt B},
pages = {124205},
doi = {10.1016/j.jhazmat.2020.124205},
pmid = {33086184},
issn = {1873-3336},
abstract = {Microplastics are emerging contaminants and widespread in the ocean, but their impacts on coral reef ecosystems are poorly understood, and in situ study is still lacking. In the present study, the distribution patterns of microplastics in the environment and inhabiting organisms were investigated along the east coast of Hainan Island, South China Sea, and the physiological impacts of the microplastics on scleractinian corals were analyzed. We documented average microplastic concentrations of 14.90 particlesL-1 in seawater, 343.04 particleskg-1 in sediment, 4.97 particlescm-2 in corals, and 0.67-3.12 particlescm-1 in Tridacnidae, Trochidae and fish intestines. Further analysis revealed that the characteristics of microplastics in the organisms were different from those in the environment, indicating preferential enrichment in the organisms. Furthermore, there was an obvious correlation between microplastic concentration and symbiotic density in corals. Furthermore, caspase3 activity was significantly positively correlated with the microplastic content in the small-polyp coral Pocillopora damicornis, but the large-polyp coral Galaxea fascicularis showed higher tolerance to microplastics. Taken together, our results suggest that microplastics are selectively enriched in corals and other reef-dwellers, in which they exact differential stress (apoptotic) effects, with the potential to impact the coral-Symbiodiniaceae symbiosis and alter the coral community structure.},
}
@article {pmid33085023,
year = {2020},
author = {Stone, LBL and Bidochka, MJ},
title = {The multifunctional lifestyles of Metarhizium: evolution and applications.},
journal = {Applied microbiology and biotechnology},
volume = {104},
number = {23},
pages = {9935-9945},
pmid = {33085023},
issn = {1432-0614},
support = {RGPIN-2014-04496//Canadian Network for Research and Innovation in Machining Technology, Natural Sciences and Engineering Research Council of Canada/ ; },
abstract = {The genus Metarhizium is comprised of a diverse group of common soil fungi that exhibit multifunctional lifestyles with varying degrees of saprotrophic, endophytic, and insect pathogenic modes of nutrient acquisition. The transcriptome of these species is modulated to reflect immediate needs of the fungus and availability of resources-a form of transcriptional plasticity that allows for physiological adaptation to environments with diverse and dynamic exploitable nutrient sources. In this review, we discuss the endophytic, insect pathogenic lifestyles of Metarhizium spp., including their symbiotic interface, origins, and evolution, and agricultural applications. Isotope labeling experiments have demonstrated that a mutually beneficial exchange of limiting nutrients occurs between the fungus and its host plant, with nitrogen derived via insect pathogenesis being translocated from Metarhizium to host plants in exchange for fixed carbon in the form of photosynthate. Thus, the endophytic and entomopathogenic abilities of Metarhizium spp. are not exclusive of one another, but rather are interdependent and reciprocal in nature. Although endophytic, insect pathogenic fungi (EIPF) could certainly have evolved from insect pathogenic fungi, phylogenomic evidence indicates that this genus is more closely related to plant-associated fungi than animal pathogens, suggesting that Metarhizium evolved from a lineage of plant symbionts, which subsequently acquired genes for insect pathogenesis. Entomopathogenicity may have been an adaptive trait, allowing for procurement of insect-derived nitrogen that could be translocated to host plants and bartered for fixed carbon, thereby improving the stability of fungal-plant symbioses. Given their ability to simultaneously parasitize soil insects, including a number of pests of agriculturally important crops, as well as promote plant health, growth, and productivity, Metarhizium spp. are considered promising alternatives to the chemical pesticides and fertilizers that have wreaked havoc on the health and integrity of ecosystems. KEY POINTS: • Metarhizium is a fungus that is an insect pathogen as well as a plant symbiont. • The genus Metarhizium has specialist and generalist insect pathogens. • Metarhizium is phylogenetically most closely related to plant endophytes.},
}
@article {pmid33083143,
year = {2020},
author = {Pyle, AE and Johnson, AM and Villareal, TA},
title = {Isolation, growth, and nitrogen fixation rates of the Hemiaulus-Richelia (diatom-cyanobacterium) symbiosis in culture.},
journal = {PeerJ},
volume = {8},
number = {},
pages = {e10115},
pmid = {33083143},
issn = {2167-8359},
abstract = {Nitrogen fixers (diazotrophs) are often an important nitrogen source to phytoplankton nutrient budgets in N-limited marine environments. Diazotrophic symbioses between cyanobacteria and diatoms can dominate nitrogen-fixation regionally, particularly in major river plumes and in open ocean mesoscale blooms. This study reports the successful isolation and growth in monocultures of multiple strains of a diatom-cyanobacteria symbiosis from the Gulf of Mexico using a modified artificial seawater medium. We document the influence of light and nutrients on nitrogen fixation and growth rates of the host diatom Hemiaulus hauckii Grunow together with its diazotrophic endosymbiont Richelia intracellularis Schmidt, as well as less complete results on the Hemiaulus membranaceus-R. intracellularis symbiosis. The symbioses rates reported here are for the joint diatom-cyanobacteria unit. Symbiont diazotrophy was sufficient to support both the host diatom and cyanobacteria symbionts, and the entire symbiosis replicated and grew without added nitrogen. Maximum growth rates of multiple strains of H. hauckii symbioses in N-free medium with N2 as the sole N source were 0.74-0.93 div d-1. Growth rates followed light saturation kinetics in H. hauckii symbioses with a growth compensation light intensity (EC) of 7-16 µmol m-2s-1and saturation light level (EK) of 84-110 µmol m-2s-1. Nitrogen fixation rates by the symbiont while within the host followed a diel pattern where rates increased from near-zero in the scotophase to a maximum 4-6 h into the photophase. At the onset of the scotophase, nitrogen-fixation rates declined over several hours to near-zero values. Nitrogen fixation also exhibited light saturation kinetics. Maximum N2 fixation rates (84 fmol N2 heterocyst-1h-1) in low light adapted cultures (50 µmol m-2s-1) were approximately 40-50% of rates (144-154 fmol N2 heterocyst-1h-1) in high light (150 and 200 µmol m-2s-1) adapted cultures. Maximum laboratory N2 fixation rates were ~6 to 8-fold higher than literature-derived field rates of the H. hauckii symbiosis. In contrast to published results on the Rhizosolenia-Richelia symbiosis, the H. hauckii symbiosis did not use nitrate when added, although ammonium was consumed by the H. hauckii symbiosis. Symbiont-free host cell cultures could not be established; however, a symbiont-free H. hauckii strain was isolated directly from the field and grown on a nitrate-based medium that would not support DDA growth. Our observations together with literature reports raise the possibility that the asymbiotic H. hauckii are lines distinct from an obligately symbiotic H. hauckii line. While brief descriptions of successful culture isolation have been published, this report provides the first detailed description of the approaches, handling, and methodologies used for successful culture of this marine symbiosis. These techniques should permit a more widespread laboratory availability of these important marine symbioses.},
}
@article {pmid33082280,
year = {2020},
author = {Khakisahneh, S and Zhang, XY and Nouri, Z and Wang, DH},
title = {Gut Microbiota and Host Thermoregulation in Response to Ambient Temperature Fluctuations.},
journal = {mSystems},
volume = {5},
number = {5},
pages = {},
pmid = {33082280},
issn = {2379-5077},
abstract = {Ambient temperature (Ta) is an important factor in shaping phenotypic plasticity. Plasticity is generally beneficial for animals in adapting to their environments. Gut microbiota are crucial in regulating host physiological and behavioral processes. However, whether the gut microbiota play a role in regulating host phenotypic plasticity under the conditions of repeated fluctuations in environmental factors has rarely been examined. We used intermittent Ta acclimations to test the hypothesis that the plasticity of gut microbiota confers on the host a metabolic adaptation to Ta fluctuations. Mongolian gerbils (Meriones unguiculatus) were acclimated to intermittent 5°C to 23°C, 37°C to 23°C or 23°C to 23°C conditions for 3 cycles (totally 3 months). Intermittent Ta acclimations induced variations in resting metabolic rate (RMR), serum thyroid hormones, and core body temperature (Tb). We further identified that the β-diversity of the microbial community varied with Ta and showed diverse responses during the 3 cycles. Some specific bacteria were more sensitive to Ta and were associated with host dynamic metabolic plasticity during Ta acclimations. In addition, depletion of gut microbiota in antibiotic-treated gerbils impaired metabolic plasticity, particularly at low Ta , whereas supplementation with propionate as an energy resource improved the inhibited thermogenic capacity and increased the survival rate in the cold. These findings demonstrate that both gut microbiota and their host were more adaptive after repeated acclimations, and dynamic gut microbiota and their metabolites may confer host plasticity in thermoregulation in response to Ta fluctuations. It also implies that low Ta is a crucial cue in driving symbiosis between mammals and their gut microbiota during evolution.IMPORTANCE Whether gut microbiota play a role in regulating host phenotypic plasticity in small mammals living in seasonal environments has rarely been examined. The present study, through an intermittent temperature acclimation model, indicates that both gut microbiota and their host were more adaptive after repeated acclimations. It also demonstrates that dynamic gut microbiota confer host plasticity in thermoregulation in response to intermittent temperature fluctuations. Furthermore, low temperature seems to be a crucial cue in driving the symbiosis between mammals and their gut microbiota during evolution.},
}
@article {pmid33081703,
year = {2020},
author = {Duplouy, A and Pranter, R and Warren-Gash, H and Tropek, R and Wahlberg, N},
title = {Towards unravelling Wolbachia global exchange: a contribution from the Bicyclus and Mylothris butterflies in the Afrotropics.},
journal = {BMC microbiology},
volume = {20},
number = {1},
pages = {319},
pmid = {33081703},
issn = {1471-2180},
support = {790531//H2020 Marie Skłodowska-Curie Actions/ ; 1328944//Academy of Finland/ ; UNCE204069//Charles University/ ; PRIMUS/17/SCI/8//Charles University/ ; Waitt Grant W163-11//National Geographic Society/ ; 2015-04441//Swedish Research Council/ ; },
abstract = {BACKGROUND: Phylogenetically closely related strains of maternally inherited endosymbiotic bacteria are often found in phylogenetically divergent, and geographically distant insect host species. The interspecies transfer of the symbiont Wolbachia has been thought to have occurred repeatedly, facilitating its observed global pandemic. Few ecological interactions have been proposed as potential routes for the horizontal transfer of Wolbachia within natural insect communities. These routes are however likely to act only at the local scale, but how they may support the global distribution of some Wolbachia strains remains unclear.
RESULTS: Here, we characterize the Wolbachia diversity in butterflies from the tropical forest regions of central Africa to discuss transfer at both local and global scales. We show that numerous species from both the Mylothris (family Pieridae) and Bicyclus (family Nymphalidae) butterfly genera are infected with similar Wolbachia strains, despite only minor interclade contacts across the life cycles of the species within their partially overlapping ecological niches. The phylogenetic distance and differences in resource use between these genera rule out the role of ancestry, hybridization, and shared host-plants in the interspecies transfer of the symbiont. Furthermore, we could not identify any shared ecological factors to explain the presence of the strains in other arthropod species from other habitats, or even ecoregions.
CONCLUSION: Only the systematic surveys of the Wolbachia strains from entire species communities may offer the material currently lacking for understanding how Wolbachia may transfer between highly different and unrelated hosts, as well as across environmental scales.},
}
@article {pmid33080083,
year = {2020},
author = {Dal Forno, M and Lawrey, JD and Sikaroodi, M and Gillevet, PM and Schuettpelz, E and Lücking, R},
title = {Extensive photobiont sharing in a rapidly radiating cyanolichen clade.},
journal = {Molecular ecology},
volume = {},
number = {},
pages = {},
doi = {10.1111/mec.15700},
pmid = {33080083},
issn = {1365-294X},
support = {0841405//Division of Environmental Biology/ ; 1609022//Division of Biological Infrastructure/ ; Global Genome Initiative (GGI-Exp_Sci-2016-069)//National Museum of Natural History/ ; Peter Buck Postdoctoral Fellowship//National Museum of Natural History/ ; },
abstract = {Recent studies have uncovered remarkable diversity in Dictyonema s.lat. basidiolichens, here recognized as subtribe Dictyonemateae. This group includes five genera and 148 species, but hundreds more await description. The photobionts of these lichens belong to Rhizonema, a recently resurrected cyanobacterial genus known by a single species. To further investigate photobiont diversity within Dictyonemateae, we generated 765 new cyanobacterial sequences from 635 specimens collected from 18 countries. The ITS barcoding locus supported the recognition of 200 mycobiont (fungal) species among these samples, but the photobiont diversity was comparatively low. Our analyses revealed three main divisions of Rhizonema, with two repeatedly recovered as monophyletic (proposed as new species), and the third mostly paraphyletic. The paraphyletic lineage corresponds to R. interruptum and partnered with mycobionts from all five genera in Dictyonemateae. There was no evidence of photobiont-mycobiont co-speciation, but one of the monophyletic lineages of Rhizonema appears to partner predominantly with one of the two major clades of Cora (mycobiont) with samples collected largely from the northern Andes. Molecular clock estimations indicate the Rhizonema species are much older than the fungal species in the Dictyonemateae, suggesting that these basidiolichens obtained their photobionts from older ascolichen lineages and the photobiont variation in extant lineages of Dictyonemateae is the result of multiple photobiont switches. These results support the hypothesis of lichens representing "fungal farmers," in which diverse mycobiont lineages associate with a substantially lower diversity of photobionts by sharing those photobionts best suited for the lichen symbiosis among multiple and often unrelated mycobiont lineages.},
}
@article {pmid33079241,
year = {2020},
author = {Ori, F and Leonardi, M and Faccio, A and Sillo, F and Iotti, M and Pacioni, G and Balestrini, R},
title = {Synthesis and ultrastructural observation of arbutoid mycorrhizae of black truffles (Tuber melanosporum and T. aestivum).},
journal = {Mycorrhiza},
volume = {30},
number = {6},
pages = {715-723},
pmid = {33079241},
issn = {1432-1890},
mesh = {*Ascomycota ; *Ericaceae ; *Mycorrhizae ; Seedlings ; Symbiosis ; },
abstract = {Arbutus unedo (the strawberry tree) is a Mediterranean shrub which forms arbutoid mycorrhizae with a variety of Asco- and Basidiomycetes. After the discovery of the mycorrhizal symbiosis between A. unedo and Tuber borchii, in this study, arbutoid mycorrhizae were synthetized in greenhouse with Tuber aestivum and Tuber melanosporum. Six months after inoculation, both species colonized the roots of all inoculated A. unedo seedlings, but mature mycorrhizae were only observed after 12 months. Ultrastructure analysis of Tuber arbutoid mycorrhizae was described for the first time, showing, as observed in typical endosymbiosis, a rearrangement of host cells and the creation of an interface compartment with both truffle species. Immunolabelling experiments suggested that pectins are not present in the interface matrix surrounding the intracellular hyphae. Thus, the ability to establish symbiosis with A. unedo seems to be a common feature in the genus Tuber, opening up the possibility to use this plant for mycorrhization with valuable truffles. This could represent an important economic opportunity in Mediterranean areas by combining the production of truffles, edible fruits and valued honey.},
}
@article {pmid33075657,
year = {2021},
author = {van Capelleveen, G and Amrit, C and Zijm, H and Yazan, DM and Abdi, A},
title = {Toward building recommender systems for the circular economy: Exploring the perils of the European Waste Catalogue.},
journal = {Journal of environmental management},
volume = {277},
number = {},
pages = {111430},
doi = {10.1016/j.jenvman.2020.111430},
pmid = {33075657},
issn = {1095-8630},
mesh = {*Algorithms ; Commerce ; Comprehension ; *Semantics ; },
abstract = {The growth in the number of industries aiming at more sustainable business processes is driving the use of the European Waste Catalogue (EWC). For example, the identification of industrial symbiosis opportunities, in which a user-generated item description has to be annotated with exactly one EWC tag from an a priori defined tag ontology. This study aims to help researchers understand the perils of the EWC when building a recommender system based on natural language processing techniques. We experiment with semantic enhancement (an EWC thesaurus) and the linguistic contexts of words (learned by Word2vec) for detecting term vector similarity in addition to direct term matching algorithms, which often fail to detect an identical term in the short text generated by users. Our in-depth analysis provides an insight into why the different recommenders were unable to generate a correct annotation and motivates a discussion on the current design of the EWC system.},
}
@article {pmid33073900,
year = {2021},
author = {CaraDonna, PJ and Burkle, LA and Schwarz, B and Resasco, J and Knight, TM and Benadi, G and Blüthgen, N and Dormann, CF and Fang, Q and Fründ, J and Gauzens, B and Kaiser-Bunbury, CN and Winfree, R and Vázquez, DP},
title = {Seeing through the static: the temporal dimension of plant-animal mutualistic interactions.},
journal = {Ecology letters},
volume = {24},
number = {1},
pages = {149-161},
doi = {10.1111/ele.13623},
pmid = {33073900},
issn = {1461-0248},
support = {DEB 1145274//National Science Foundation/ ; Friedrich Wilhelm Bessel Research Award : Alexander von Humboldt Professorship//Alexander von Humboldt-Stiftung/ ; FP7/2007-2013//FP7 People: Marie-Curie Actions/ ; BE 6231/1-//Deutsche Forschungsgemeinschaft/ ; FR 3364/4-1//Deutsche Forschungsgemeinschaft/ ; FZT 118//Deutsche Forschungsgemeinschaft/ ; Heisenberg Fellowship KA 3349/3-1//Deutsche Forschungsgemeinschaft/ ; Short-term scholarship//Deutscher Akademischer Austauschdienst/ ; PICT-2014-3168//Fondo para la Investigación Científica y Tecnológica/ ; //Helmholtz Association/ ; //Alexander von Humboldt-Stiftung/ ; //Helmholtz-Gemeinschaft/ ; //Seventh Framework Programme/ ; },
mesh = {Animals ; Ecosystem ; Plants ; *Pollination ; *Symbiosis ; },
abstract = {Most studies of plant-animal mutualistic networks have come from a temporally static perspective. This approach has revealed general patterns in network structure, but limits our ability to understand the ecological and evolutionary processes that shape these networks and to predict the consequences of natural and human-driven disturbance on species interactions. We review the growing literature on temporal dynamics of plant-animal mutualistic networks including pollination, seed dispersal and ant defence mutualisms. We then discuss potential mechanisms underlying such variation in interactions, ranging from behavioural and physiological processes at the finest temporal scales to ecological and evolutionary processes at the broadest. We find that at the finest temporal scales (days, weeks, months) mutualistic interactions are highly dynamic, with considerable variation in network structure. At intermediate scales (years, decades), networks still exhibit high levels of temporal variation, but such variation appears to influence network properties only weakly. At the broadest temporal scales (many decades, centuries and beyond), continued shifts in interactions appear to reshape network structure, leading to dramatic community changes, including loss of species and function. Our review highlights the importance of considering the temporal dimension for understanding the ecology and evolution of complex webs of mutualistic interactions.},
}
@article {pmid33072048,
year = {2020},
author = {Guo, DJ and Singh, RK and Singh, P and Li, DP and Sharma, A and Xing, YX and Song, XP and Yang, LT and Li, YR},
title = {Complete Genome Sequence of Enterobacter roggenkampii ED5, a Nitrogen Fixing Plant Growth Promoting Endophytic Bacterium With Biocontrol and Stress Tolerance Properties, Isolated From Sugarcane Root.},
journal = {Frontiers in microbiology},
volume = {11},
number = {},
pages = {580081},
pmid = {33072048},
issn = {1664-302X},
abstract = {Sugarcane is the leading economic crop in China, requires huge quantities of nitrogen in the preliminary plant growth stages. However, the use of an enormous amount of nitrogen fertilizer increases the production price, and have detrimental results on the environment, causes severe soil and water pollution. In this study, a total of 175 endophytic strains were obtained from the sugarcane roots, belonging to five different species, i.e., Saccharum officinarum, Saccharum barberi, Saccharum robustum, Saccharum spontaneum, and Saccharum sinense. Among these, only 23 Enterobacter strains were chosen based on nitrogen fixation, PGP traits, hydrolytic enzymes production, and antifungal activities. Also, all selected strains were showed diverse growth range under different stress conditions, i.e., pH (5-10), temperature (20-45°C), and NaCl (7-12%) and 14 strains confirmed positive nifH, and 12 strains for acdS gene amplification, suggested that these strains could fix nitrogen along with stress tolerance properties. Out of 23 selected strains, Enterobacter roggenkampii ED5 was the most potent strain. Hence, this strain was further selected for comprehensive genome analysis, which includes a genome size of 4,702,851 bp and 56.05% of the average G + C content. Genome annotations estimated 4349 protein-coding with 83 tRNA and 25 rRNA genes. The CDSs number allocated to the KEGG, COG, and GO database were 2839, 4028, and 2949. We recognized a total set of genes that are possibly concerned with ACC deaminase activity, siderophores and plant hormones production, nitrogen and phosphate metabolism, symbiosis, root colonization, biofilm formation, sulfur assimilation and metabolism, along with resistance response toward a range of biotic and abiotic stresses. E. roggenkampii ED5 strain was also a proficient colonizer in sugarcane (variety GT11) and enhanced growth of sugarcane under the greenhouse. To the best of our knowledge, this is the first information on the whole-genome sequence study of endophytic E. roggenkampii ED5 bacterium associated with sugarcane root. And, our findings proposed that identification of predicted genes and metabolic pathways might describe this strain an eco-friendly bioresource to promote sugarcane growth by several mechanisms of actions under multi-stresses.},
}
@article {pmid33072023,
year = {2020},
author = {Dias, T and Pimentel, V and Cogo, AJD and Costa, R and Bertolazi, AA and Miranda, C and de Souza, SB and Melo, J and Carolino, M and Varma, A and Eutrópio, F and Olivares, FL and Ramos, AC and Cruz, C},
title = {The Free-Living Stage Growth Conditions of the Endophytic Fungus Serendipita indica May Regulate Its Potential as Plant Growth Promoting Microbe.},
journal = {Frontiers in microbiology},
volume = {11},
number = {},
pages = {562238},
pmid = {33072023},
issn = {1664-302X},
abstract = {Serendipita indica (former Piriformospora indica) is a non-obligate endophytic fungus and generally a plant growth and defence promoter with high potential to be used in agriculture. However, S. indica may switch from biotrophy to saprotrophy losing its plant growth promoting traits. Our aim was to understand if the free-living stage growth conditions (namely C availability) regulate S. indica's phenotype, and its potential as plant-growth-promoting-microbe (PGPM). We grew S. indica in its free-living stage under increasing C availabilities (2-20 g L-1 of glucose or sucrose). We first characterised the effect of C availability during free-living stage growth on fungal phenotype: colonies growth and physiology (plasma membrane proton pumps, stable isotopic signatures, and potential extracellular decomposing enzymes). The effect of the C availability during the free-living stage of the PGPM was evaluated on wheat. We observed that C availability during the free-living stage regulated S. indica's growth, ultrastructure and physiology, resulting in two distinct colony phenotypes: compact and explorer. The compact phenotype developed at low C, used peptone as the major C and N source, and displayed higher decomposing potential for C providing substrates; while the explorer phenotype developed at high C, used glucose and sucrose as major C sources and casein and yeast extract as major N sources, and displayed higher decomposing potential for N and P providing substrates. The C availability, or the C/N ratio, during the free-living stage left a legacy to the symbiosis stage, regulating S. indica's potential to promote plant growth: wheat growth promotion by the explorer phenotype was ± 40% higher than that by the compact phenotype. Our study highlights the importance of considering microbial ecology in designing PGPM/biofertilizers. Further studies are needed to test the phenotypes under more extreme conditions, and to understand if the in vitro acquired characteristics persist under field conditions.},
}
@article {pmid33071821,
year = {2020},
author = {Goulet, TL and Erill, I and Ascunce, MS and Finley, SJ and Javan, GT},
title = {Conceptualization of the Holobiont Paradigm as It Pertains to Corals.},
journal = {Frontiers in physiology},
volume = {11},
number = {},
pages = {566968},
pmid = {33071821},
issn = {1664-042X},
abstract = {Corals' obligate association with unicellular dinoflagellates, family Symbiodiniaceae form the foundation of coral reefs. For nearly a century, researchers have delved into understanding the coral-algal mutualism from multiple levels of resolution and perspectives, and the questions and scope have evolved with each iteration of new techniques. Advances in genetic technologies not only aided in distinguishing between the multitude of Symbiodiniaceae but also illuminated the existence and diversity of other organisms constituting the coral microbiome. The coral therefore is a meta-organism, often referred to as the coral holobiont. In this review, we address the importance of including a holistic perspective to understanding the coral holobiont. We also discuss the ramifications of how different genotypic combinations of the coral consortium affect the holobiont entity. We highlight the paucity of data on most of the coral microbiome. Using Symbiodiniaceae data, we present evidence that the holobiont properties are not necessarily the sum of its parts. We then discuss the consequences of the holobiont attributes to the fitness of the holobiont and the myriad of organisms that contribute to it. Considering the complexity of host-symbiont genotypic combinations will aid in our understanding of coral resilience, robustness, acclimation, and/or adaptation in the face of environmental change and increasing perturbations.},
}
@article {pmid33070356,
year = {2020},
author = {Creed, RP and Skelton, J and Farrell, KJ and Brown, BL},
title = {Strong effects of a mutualism on freshwater community structure.},
journal = {Ecology},
volume = {},
number = {},
pages = {e03225},
doi = {10.1002/ecy.3225},
pmid = {33070356},
issn = {1939-9170},
support = {DEB-0949780//National Science Foundation/ ; DEB-0949823//National Science Foundation/ ; //Biology Department at Appalachian State University/ ; //Clemson University/ ; //Virginia Tech/ ; },
abstract = {Numerous mutualisms have been described from terrestrial and marine communities and many of these mutualisms have significant effects on community structure and function. In contrast, there are far fewer examples of mutualisms from freshwater habitats and there is no evidence that any mutualism has community-wide or ecosystem-level consequences. Northern hemisphere crayfish are host to a variety of ectosymbiotic worms called branchiobdellidans. The association between some of these "crayfish worms" and their hosts is a mutualism. The outcome of the association is context dependent and can be influenced by host size, symbiont number, and the environment. Here we document in two experiments that the mutualism between crayfish and these worms alters the effect of crayfish on stream community structure and sediment deposition, an important ecosystem variable. We enclosed crayfish stocked with 0 worms and intermediate (3-6) and high worm densities (12) in cages in streams in Boone, North Carolina and Clemson, South Carolina, United States. At both locations, there was a negative relationship between initial worm density and final macroinvertebrate abundance. There was a significant effect of worm treatment on macroinvertebrate community structure in both the Boone and Clemson experiments. In Boone, there were effects on both overall macroinvertebrate abundance and community composition, whereas in Clemson, changes to community structure were primarily driven by changes in total abundance. There was a negative relationship between benthic sediment volume and initial worm density in both experiments, primarily later in the experiments, though these effects were influenced by sediment deposition rates. Our results are the first to demonstrate strong effects of a mutualism on freshwater communities. Both members of this mutualism are found throughout the northern hemisphere, so similar impacts may occur in many other waterways. Given that various species in addition to crayfish function as keystone species and ecosystem engineers in freshwater systems throughout the world, mutualisms involving these strongly interacting species may be as important to the structure and functioning of freshwater systems as comparable mutualisms in marine and terrestrial systems.},
}
@article {pmid33068168,
year = {2020},
author = {Rodrigues, TF and Bender, FR and Sanzovo, AWS and Ferreira, E and Nogueira, MA and Hungria, M},
title = {Impact of pesticides in properties of Bradyrhizobium spp. and in the symbiotic performance with soybean.},
journal = {World journal of microbiology & biotechnology},
volume = {36},
number = {11},
pages = {172},
doi = {10.1007/s11274-020-02949-5},
pmid = {33068168},
issn = {1573-0972},
support = {CNPq 465133/2014-2, Fundação Araucária-STI-043/2019, CAPES//INCT-Plant-Growth Promoting Microorganisms for Agricultural Sustainability and Environmental Responsibility/ ; 400468/2016-6//Conselho Nacional de Desenvolvimento Científico e Tecnológico/ ; },
abstract = {Soybean [Glycine max (L.) Merr.] has great economic and nutritional importance mainly due to its high protein content. All plant's N needs can be met by the symbiosis with elite Bradyrhizobium strains applied as inoculants to the seeds at sowing time; however, the increasing use of pesticides in seed treatments can impair the contribution of the biological nitrogen fixation. In this study, we report decreases in cell survival of two strains, B. japonicum SEMIA 5079 and B. elkanii SEMIA 587 in seeds inoculated and treated with StandakTop™, composed of the fungicides pyraclostrobin and thiophanate-methyl and the insecticide fipronil, the pesticides most used in soybean seed treatment in several countries. Cell death was enhanced with the time of exposure to the pesticides, and B. elkanii was less tolerant, with almost no detectable viable cells after 15 days. Change in colony morphology with smaller colonies was observed in the presence of the pesticides, being more drastic with the time of exposure, and attributed to an adaptive response towards survival in the presence of the abiotic stress. However, morphological changes were reversible after elimination of the stressing agent and symbiotic performance under controlled greenhouse conditions was similar between strains that had been or not exposed to the pesticides. In addition, no changes in DNA profiles (BOX-PCR) of both strains were observed after the contact with the pesticides. In two field experiments, impacting effects of the pesticides were observed mainly on the total N accumulated in grains of plants relying on both N2-fixation and N-fertilizer. Our data indicate that StandakTop® affects parameters never reported before, including colony morphology of Bradyrhizobium spp. and N metabolism and/or N remobilization to soybean grains.},
}
@article {pmid33068149,
year = {2020},
author = {Mabaso, N and Tinarwo, P and Abbai, N},
title = {Lack of association between Mycoplasma hominis and Trichomonas vaginalis symbiosis in relation to metronidazole resistance.},
journal = {Parasitology research},
volume = {119},
number = {12},
pages = {4197-4204},
doi = {10.1007/s00436-020-06930-x},
pmid = {33068149},
issn = {1432-1955},
support = {636713//Inyuvesi Yakwazulu-Natali/ ; },
mesh = {Adult ; Antiprotozoal Agents/pharmacology ; *Drug Resistance ; Female ; Humans ; Metronidazole/*pharmacology ; Mycoplasma hominis/isolation & purification/*physiology ; Parasitic Sensitivity Tests ; Pregnancy ; South Africa/epidemiology ; *Symbiosis ; Trichomonas Vaginitis/epidemiology/microbiology/parasitology ; Trichomonas vaginalis/drug effects/*microbiology ; },
abstract = {Resistance mechanisms of Trichomonas vaginalis to metronidazole are still not well understood. It has been shown that Mycoplasma hominis has the ability to establish an endosymbiotic relationship with T. vaginalis. This study investigated the association between T. vaginalis and M. hominis symbiosis in relation to metronidazole resistance. This study included 362 pregnant women from the King Edward VIII hospital in South Africa. The women provided self-collected vaginal swabs for the diagnosis of T. vaginalis by culture. Metronidazole susceptibility using the broth-microdilution assay was performed. Detection of the 16S rRNA from M. hominis using T. vaginalis genomic DNA as the template was performed. All statistical analysis was conducted in R statistical computing software. A total of 21 culture positive isolates were obtained resulting in a prevalence of 5.8% for T. vaginalis in the study population. Under anaerobic incubation, 52.4% (11/21) of the isolates were susceptible to metronidazole (MIC ≤ 1 μg/ml). Intermediate resistance (MIC of 2 μg/ml) and full resistance (4 μg/ml) was observed in 38.1% (8/21) and 9.5% (2/21) of the isolates, respectively. The majority of the isolates 95% (19/20) were susceptible to metronidazole under aerobic conditions. Only one isolate had a MIC of 50 μg/ml. M. hominis was shown to be present in 85.7% (18/21) of the T. vaginalis isolates. However, there was no significant association between metronidazole susceptibility and T. vaginalis-M. hominis symbiosis. This study provides evidence of emerging metronidazole resistance in T. vaginalis. However, these resistance profiles were not associated with M. hominis symbiosis.},
}
@article {pmid33067828,
year = {2020},
author = {Mens, C and Hastwell, AH and Su, H and Gresshoff, PM and Mathesius, U and Ferguson, BJ},
title = {Characterisation of Medicago truncatula CLE34 and CLE35 in nitrate and rhizobia regulation of nodulation.},
journal = {The New phytologist},
volume = {},
number = {},
pages = {},
doi = {10.1111/nph.17010},
pmid = {33067828},
issn = {1469-8137},
support = {DP130102266//Australian Research Council/ ; DP130103084//Australian Research Council/ ; DP190102996//Australian Research Council/ ; //Hermon Slade Foundation/ ; },
abstract = {Legumes form a symbiosis with atmospheric nitrogen (N2)-fixing soil rhizobia, resulting in new root organs called nodules that enable N2 -fixation. Nodulation is a costly process that is tightly regulated by the host through autoregulation of nodulation (AON) and nitrate-dependent regulation of nodulation. Both pathways require legume-specific CLAVATA/ESR-related (CLE) peptides. Nitrogen-induced nodulation-suppressing CLE peptides have not previously been investigated in Medicago truncatula, for which only rhizobia-induced MtCLE12 and MtCLE13 have been characterised. Here, we report on novel peptides MtCLE34 and MtCLE35 in nodulation control. The nodulation-suppressing CLE peptides of five legume species were classified into three clades based on sequence homology and phylogeny. This approached identified MtCLE34 and MtCLE35 and four new CLE peptide orthologues of Pisum sativum. Whereas MtCLE12 and MtCLE13 are induced by rhizobia, MtCLE34 and MtCLE35 respond to both rhizobia and nitrate. MtCLE34 was identified as a pseudogene lacking a functional CLE-domain. MtCLE35 was found to inhibit nodulation in a SUNN- and RDN1-dependent manner via overexpression analysis. Together, our findings indicate that MtCLE12 and MtCLE13 have a specific role in AON, while MtCLE35 regulates nodule numbers in response to both rhizobia and nitrate. MtCLE34 likely had a similar role to MtCLE35, but its function was lost due to a premature nonsense mutation.},
}
@article {pmid33067391,
year = {2020},
author = {Koch, EJ and Bongrand, C and Bennett, BD and Lawhorn, S and Moriano-Gutierrez, S and Pende, M and Vadiwala, K and Dodt, HU and Raible, F and Goldman, W and Ruby, EG and McFall-Ngai, M},
title = {The cytokine MIF controls daily rhythms of symbiont nutrition in an animal-bacterial association.},
journal = {Proceedings of the National Academy of Sciences of the United States of America},
volume = {117},
number = {44},
pages = {27578-27586},
pmid = {33067391},
issn = {1091-6490},
support = {P20 GM125508/GM/NIGMS NIH HHS/United States ; R01 AI050661/AI/NIAID NIH HHS/United States ; R01 GM135254/GM/NIGMS NIH HHS/United States ; R01 OD011024/OD/NIH HHS/United States ; R37 AI050661/AI/NIAID NIH HHS/United States ; },
abstract = {The recent recognition that many symbioses exhibit daily rhythms has encouraged research into the partner dialogue that drives these biological oscillations. Here we characterized the pivotal role of the versatile cytokine macrophage migration inhibitory factor (MIF) in regulating a metabolic rhythm in the model light-organ symbiosis between Euprymna scolopes and Vibrio fischeri As the juvenile host matures, it develops complex daily rhythms characterized by profound changes in the association, from gene expression to behavior. One such rhythm is a diurnal shift in symbiont metabolism triggered by the periodic provision of a specific nutrient by the mature host: each night the symbionts catabolize chitin released from hemocytes (phagocytic immune cells) that traffic into the light-organ crypts, where the population of V. fischeri cells resides. Nocturnal migration of these macrophage-like cells, together with identification of an E. scolopes MIF (EsMIF) in the light-organ transcriptome, led us to ask whether EsMIF might be the gatekeeper controlling the periodic movement of the hemocytes. Western blots, ELISAs, and confocal immunocytochemistry showed EsMIF was at highest abundance in the light organ. Its concentration there was lowest at night, when hemocytes entered the crypts. EsMIF inhibited migration of isolated hemocytes, whereas exported bacterial products, including peptidoglycan derivatives and secreted chitin catabolites, induced migration. These results provide evidence that the nocturnal decrease in EsMIF concentration permits the hemocytes to be drawn into the crypts, delivering chitin. This nutritional function for a cytokine offers the basis for the diurnal rhythms underlying a dynamic symbiotic conversation.},
}
@article {pmid33066763,
year = {2020},
author = {Murarkar, S and Gothankar, J and Doke, P and Pore, P and Lalwani, S and Dhumale, G and Quraishi, S and Patil, R and Waghachavare, V and Dhobale, R and Rasote, K and Palkar, S and Malshe, N},
title = {Prevalence and determinants of undernutrition among under-five children residing in urban slums and rural area, Maharashtra, India: a community-based cross-sectional study.},
journal = {BMC public health},
volume = {20},
number = {1},
pages = {1559},
pmid = {33066763},
issn = {1471-2458},
support = {OPP1084307/GATES/Bill & Melinda Gates Foundation/United States ; },
mesh = {Adult ; Child Nutrition Disorders/*epidemiology ; Child, Preschool ; Cross-Sectional Studies ; Female ; Humans ; India/epidemiology ; Infant ; Male ; Mothers/statistics & numerical data ; *Poverty Areas ; Prevalence ; Risk Factors ; Rural Population/*statistics & numerical data ; Socioeconomic Factors ; Urban Population/*statistics & numerical data ; },
abstract = {BACKGROUND: Undernutrition among under five children in India is a major public health problem. Despite India's growth in the economy, the child mortality rate due to undernutrition is still high in both urban and rural areas. Studies that focus on urban slums are scarce. Hence the present study was carried out to assess the prevalence and determinants of undernutrition in children under five in Maharashtra, India.
METHODS: A community-based cross-sectional study was conducted in 16 randomly selected clusters in two districts of Maharashtra state, India. Data were collected through house to house survey by interviewing mothers of under five children. Total 2929 mothers and their 3671 under five children were covered. Multivariate logistic regression analysis was carried out to identify the determinants of child nutritional status seperately in urban and rural areas.
RESULTS: The mean age of the children was 2.38 years (±SD 1.36) and mean age of mothers was 24.25 years (± SD 6.37). Overall prevalence of stunting among children under five was 45.9%, wasting was 17.1 and 35.4% children were underweight. Prevalence of wasting, stunting and underweight were more seen in an urban slum than a rural area. In the rural areas exclusive breast feeding (p < 0.001) and acute diarrhea (p = 0.001) were associated with wasting, children with birth order 2 or less than 2 were associated with stunting and exclusive breast feeding (p < 0.05) and low maternal education were associated with underweight. Whereas in the urban slums exclusive breast feeding (p < 0.05) was associated with wasting, sex of the child (p < 0.05) and type of family (p < 0.05) were associated with stunting,and low income of the family (p < 0.05) was associated with underweight.
CONCLUSIONS: Factors like sex of the child, birth order,exclusive breast feeding,economic status of the family, type of family,acute diarrhea and maternal education have influence on nutritional status of the child. Improvement of maternal education will improve the nutritional status of the child. Strategies are needed to improve the economic status of the community.
TRIAL REGISTRATION: Trial registration number: CTRI/2017/12/010881 ; Registration date:14/12/2017. Retrospectively registered.},
}
@article {pmid33064903,
year = {2020},
author = {Hoysted, GA and Bidartondo, MI and Duckett, JG and Pressel, S and Field, KJ},
title = {Phenology and function in lycopod-Mucoromycotina symbiosis.},
journal = {The New phytologist},
volume = {},
number = {},
pages = {},
doi = {10.1111/nph.17009},
pmid = {33064903},
issn = {1469-8137},
support = {NE/N00941X/1//Natural Environment Research Council/ ; NE/N009665/1//Natural Environment Research Council/ ; NE/S009663/1//Natural Environment Research Council/ ; PLP-2017-079//Leverhulme Trust/ ; BB/M026825/1/BB_/Biotechnology and Biological Sciences Research Council/United Kingdom ; },
}
@article {pmid33064769,
year = {2020},
author = {Pons, S and Fournier, S and Chervin, C and Bécard, G and Rochange, S and Frei Dit Frey, N and Puech Pagès, V},
title = {Phytohormone production by the arbuscular mycorrhizal fungus Rhizophagus irregularis.},
journal = {PloS one},
volume = {15},
number = {10},
pages = {e0240886},
pmid = {33064769},
issn = {1932-6203},
mesh = {Chromatography, Gas ; Chromatography, High Pressure Liquid ; Cytokinins/analysis/metabolism ; Ethylenes/analysis/metabolism ; Fungi/*metabolism ; Gibberellins/analysis/metabolism ; Indoleacetic Acids/analysis/metabolism ; Mass Spectrometry ; Mycorrhizae/metabolism ; Plant Growth Regulators/*analysis/metabolism ; Spores, Fungal/metabolism ; Symbiosis ; },
abstract = {Arbuscular mycorrhizal symbiosis is a mutualistic interaction between most land plants and fungi of the glomeromycotina subphylum. The initiation, development and regulation of this symbiosis involve numerous signalling events between and within the symbiotic partners. Among other signals, phytohormones are known to play important roles at various stages of the interaction. During presymbiotic steps, plant roots exude strigolactones which stimulate fungal spore germination and hyphal branching, and promote the initiation of symbiosis. At later stages, different plant hormone classes can act as positive or negative regulators of the interaction. Although the fungus is known to reciprocally emit regulatory signals, its potential contribution to the phytohormonal pool has received little attention, and has so far only been addressed by indirect assays. In this study, using mass spectrometry, we analyzed phytohormones released into the medium by germinated spores of the arbuscular mycorrhizal fungus Rhizophagus irregularis. We detected the presence of a cytokinin (isopentenyl adenosine) and an auxin (indole-acetic acid). In addition, we identified a gibberellin (gibberellin A4) in spore extracts. We also used gas chromatography to show that R. irregularis produces ethylene from methionine and the α-keto γ-methylthio butyric acid pathway. These results highlight the possibility for AM fungi to use phytohormones to interact with their host plants, or to regulate their own development.},
}
@article {pmid33064761,
year = {2020},
author = {Selwyn, M and Garrote, PJ and Castilla, AR and Fedriani, JM},
title = {Interspecific interactions among functionally diverse frugivores and their outcomes for plant reproduction: A new approach based on camera-trap data and tailored null models.},
journal = {PloS one},
volume = {15},
number = {10},
pages = {e0240614},
pmid = {33064761},
issn = {1932-6203},
mesh = {Animals ; Birds/physiology ; Deer/*physiology ; Feeding Behavior/*physiology ; Fruit/physiology ; Herbivory/*physiology ; Plant Development/*physiology ; Reproduction/physiology ; Seed Dispersal/physiology ; Spain ; Symbiosis/physiology ; Trees/physiology ; },
abstract = {The study of plant-frugivore interactions is essential to understand the ecology and evolution of many plant communities. However, very little is known about how interactions among frugivores indirectly affect plant reproductive success. In this study, we examined direct interactions among vertebrate frugivores sharing the same fruit resources. Then, we inferred how the revealed direct interspecific interactions could lead to indirect (positive or negative) effects on reproductive success of fleshy fruited plants. To do so, we developed a new analytical approach that combines camera trap data (spatial location, visitor species, date and time, activity) and tailored null models that allowed us to infer spatial-temporal interactions (attraction, avoidance or indifference) between pairs of frugivore species. To illustrate our approach, we chose to study the system composed by the Mediterranean dwarf palm, Chamaerops humilis, the Iberian pear tree, Pyrus bourgaeana, and their shared functionally diverse assemblages of vertebrate frugivores in a Mediterranean area of SW Spain. We first assessed the extent to which different pairs of frugivore species tend to visit the same or different fruiting individual plants. Then, for pairs of species that used the same individual plants, we evaluated their spatial-temporal relationship. Our first step showed, for instance, that some prey frugivore species (e.g. lagomorphs) tend to avoid those C. humilis individuals that were most visited by their predators (e.g. red foxes). Also, the second step revealed temporal attraction between large wild and domestic frugivore ungulates (e.g. red deer, cows) and medium-sized frugivores (e.g. red foxes) suggesting that large mammals could facilitate the C. humilis and P. bourgaeana exploitation to other smaller frugivores by making fruits more easily accessible. Finally, our results allowed us to identify direct interaction pathways, that revealed how the mutualistic and antagonistic relations between animal associates derived into indirect effects on both plants seed dispersal success. For instance, we found that large-sized seed predators (e.g. ungulates) had a direct positive effect on the likelihood of visits by legitimate seed dispersers (e.g. red foxes) to both fleshy fruited plants. Then, seed predators showed an indirect positive effect on the plants' reproductive success. Our new analytical approach provides a widely applicable framework for further studies on multispecies interactions in different systems beyond plant-frugivore interactions, including plant-pollinator interactions, the exploitation of plants by herbivores, and the use of carcasses by vertebrate scavengers.},
}
@article {pmid33060360,
year = {2020},
author = {Vidal, MC and Wang, SP and Rivers, DM and Althoff, DM and Segraves, KA},
title = {Species richness and redundancy promote persistence of exploited mutualisms in yeast.},
journal = {Science (New York, N.Y.)},
volume = {370},
number = {6514},
pages = {346-350},
doi = {10.1126/science.abb6703},
pmid = {33060360},
issn = {1095-9203},
mesh = {Adenine/metabolism ; Biota ; Lysine/genetics/metabolism ; Saccharomyces cerevisiae/genetics/*physiology ; Symbiosis/genetics/*physiology ; },
abstract = {Mutualisms, or reciprocally beneficial interspecific interactions, constitute the foundation of many ecological communities and agricultural systems. Mutualisms come in different forms, from pairwise interactions to extremely diverse communities, and they are continually challenged with exploitation by nonmutualistic community members (exploiters). Thus, understanding how mutualisms persist remains an essential question in ecology. Theory suggests that high species richness and functional redundancy could promote mutualism persistence in complex mutualistic communities. Using a yeast system (Saccharomyces cerevisiae), we experimentally show that communities with the greatest mutualist richness and functional redundancy are nearly two times more likely to survive exploitation than are simple communities. Persistence increased because diverse communities were better able to mitigate the negative effects of competition with exploiters. Thus, large mutualistic networks may be inherently buffered from exploitation.},
}
@article {pmid33059931,
year = {2020},
author = {Das, M and Kale, V},
title = {Extracellular vesicles: Mediators of embryo-maternal crosstalk during pregnancy and a new weapon to fight against infertility.},
journal = {European journal of cell biology},
volume = {99},
number = {8},
pages = {151125},
doi = {10.1016/j.ejcb.2020.151125},
pmid = {33059931},
issn = {1618-1298},
abstract = {In modern-day life, infertility is one of the major issues that can affect an individual, both physically and psychologically. Several anatomical, physiological, and genetic factors might contribute to the infertility of an individual. Intercellular communication between trophectoderm and endometrial epithelium triggers successful embryo implantation and thereby establishes pregnancy. Recent studies demonstrate that Extracellular vesicles (EVs) are emerging as one of the crucial components that are involved in embryo-maternal communication and promote pregnancy. Membrane-bound EVs release several secreted factors within the uterine fluid, which mediates an intermolecular transfer of EVs' cargos between blastocysts and endometrium. Emerging evidences indicate that several events like imbalance in the release of endometrial or placenta-derived EVs (exosomes/MVs), uptake of their content, failure of embryo selection might lead to implantation failure. Here in this review, we have discussed the current knowledge of the involvement of EVs in maternal-fetal communications during implantation and also highlighted the EVs' rejuvenating ability to overcome infertility-related issues. We also discussed the alteration of the EVs' cargo in different pathological conditions that lead to infertility. Therefore, this review would give a better understanding of EVs' contribution in successful embryo implantation, which could help in the development of new diagnostic tools and cell-free biologics to improve the in vivo reproductive process and to treat infertility by restoring normal reproductive functions.},
}
@article {pmid33059667,
year = {2020},
author = {Doering, JA and Booth, T and Wiersma, YF and Piercey-Normore, MD},
title = {How do genes flow? Identifying potential dispersal mode for the semi-aquatic lichen Dermatocarpon luridum using spatial modelling and photobiont markers.},
journal = {BMC ecology},
volume = {20},
number = {1},
pages = {56},
pmid = {33059667},
issn = {1472-6785},
support = {CGS-M//Canadian Network for Research and Innovation in Machining Technology, Natural Sciences and Engineering Research Council of Canada/International ; Discovery//Canadian Network for Research and Innovation in Machining Technology, Natural Sciences and Engineering Research Council of Canada/International ; },
mesh = {Gene Flow ; Genetics, Population ; Genotype ; *Lichens/genetics ; Symbiosis ; },
abstract = {BACKGROUND: Landscape genetics is an interdisciplinary field that combines tools and techniques from population genetics with the spatially explicit principles from landscape ecology. Spatial variation in genotypes is used to test hypotheses about how landscape pattern affects dispersal in a wide range of taxa. Lichens, symbiotic associations between mycobionts and photobionts, are an entity for which little is known about their dispersal mechanism. Our objective was to infer the dispersal mechanism in the semi-aquatic lichen Dermatocarpon luridum using spatial models and the spatial variation of the photobiont, Diplosphaera chodatii. We sequenced the ITS rDNA and the β-actin gene regions of the photobiont and mapped the haplotype spatial distribution in Payuk Lake. We subdivided Payuk Lake into subpopulations and applied four spatial models based on the topography and hydrology to infer the dispersal mechanism.
RESULTS: Genetic variation corresponded with the topography of the lake and the net flow of water through the waterbody. A lack of isolation-by-distance suggests high gene flow or dispersal within the lake. We infer the dispersal mechanism in D. luridum could either be by wind and/or water based on the haplotype spatial distribution of its photobiont using the ITS rDNA and β-actin markers.
CONCLUSIONS: We inferred that the dispersal mechanism could be either wind and/or water dispersed due to the conflicting interpretations of our landscape hypotheses. This is the first study to use spatial modelling to infer dispersal in semi-aquatic lichens. The results of this study may help to understand lichen dispersal within aquatic landscapes, which can have implications in the conservation of rare or threatened lichens.},
}
@article {pmid33059155,
year = {2020},
author = {Herrera-Belaroussi, A and Normand, P and Pawlowski, K and Fernandez, MP and Wibberg, D and Kalinowski, J and Brachmann, A and Berckx, F and Lee, N and Blom, J and Pozzi, AC and Fournier, P and Bethencourt, L and Dubost, A and Abrouk, D and Sellstedt, A},
title = {Candidatus Frankia nodulisporulans sp. nov., an Alnus glutinosa-infective Frankia species unable to grow in pure culture and able to sporulate in-planta.},
journal = {Systematic and applied microbiology},
volume = {43},
number = {6},
pages = {126134},
doi = {10.1016/j.syapm.2020.126134},
pmid = {33059155},
issn = {1618-0984},
abstract = {We describe a new Frankia species, for three non-isolated strains obtained from Alnus glutinosa in France and Sweden, respectively. These strains can nodulate several Alnus species (A. glutinosa, A. incana, A. alnobetula), they form hyphae, vesicles and sporangia in the root nodule cortex but have resisted all attempts at isolation in pure culture. Their genomes have been sequenced, they are significantly smaller than those of other Alnus-infective species (5Mb instead of 7.5Mb) and are very closely related to one another (ANI of 100%). The name Candidatus Frankia nodulisporulans is proposed. The GenBank/EMBL/DDBJ accession numbers for the 16S rRNA gene and draft genome sequences reported in this study for AgTrS, AgUmASt1 and AgUmASH1 are MT023539/LR778176/LR778180 and NZ_CADCWS000000000.1/CADDZU010000001/CADDZW010000001, respectively.},
}
@article {pmid33059057,
year = {2020},
author = {Khasa, R and Sharma, P and Vaidya, A and Vrati, S and Kalia, M},
title = {Proteins involved in actin filament organization are key host factors for Japanese encephalitis virus life-cycle in human neuronal cells.},
journal = {Microbial pathogenesis},
volume = {149},
number = {},
pages = {104565},
doi = {10.1016/j.micpath.2020.104565},
pmid = {33059057},
issn = {1096-1208},
abstract = {Multiple membrane trafficking networks operate in the eukaryotic cell and are hijacked by viruses to establish infection. Recent studied have highlighted that viruses can exploit distinct pathways depending on the cell type. Japanese encephalitis virus (JEV), a neurotropic flavivirus, can infect neuronal cells through a clathrin-independent endocytic mechanism. To further characterize the membrane trafficking requirements for JEV infection of neuronal cells, we have performed a RNA interference-based study targeting 136 proteins in the human cell line IMR-32. Through quantitative RT-PCR and plaque assays we have validated that JEV infection in neuronal cells was independent of clathrin, and identified host-factors that were crucial for establishment of infection. Several of these proteins were involved in regulation of actin filament organization such as RHOA, RAC1, proteins of the ARP2/3 complex and N-WASP family, LIMK1, PAK1 and ROCK2. The small molecule inhibitors of ARP2/3 complex, CK-548 and of the N-WASP, Wiskostatin inhibited virus replication highlighting the important roles of these proteins in the virus life-cycle. We also identified ATG12, BECN1, VAPA, VAPB and VCP proteins as crucial host-factors for JEV replication across epithelial and neuronal cell lineages.},
}
@article {pmid33056606,
year = {2020},
author = {Prakash, S and Marimuthu, N},
title = {Notes on some crinoid associated decapod crustaceans (Crustacea: Decapoda) of Lakshadweep Archipelago, Central Indian Ocean.},
journal = {Zootaxa},
volume = {4766},
number = {1},
pages = {zootaxa.4766.1.4},
doi = {10.11646/zootaxa.4766.1.4},
pmid = {33056606},
issn = {1175-5334},
mesh = {Animals ; Coral Reefs ; *Decapoda ; Indian Ocean ; },
abstract = {Decapod crustaceans symbiotic with echinoderms (sea stars, brittle stars, feather stars, basket stars, sea cucumbers, and sea urchins) possess remarkable diversification in the Indo-Pacific. In the present study, seven species of decapod crustaceans symbiotic with crinoids are recorded based on collections from selected Islands (Agatti, Amini, Bangaram, Kavaratti, Kalpeni, and Minicoy) of Lakshadweep Archipelago. Of these decapods, five caridean shrimps (Alpheidae: Synalpheus carinatus (de Man, 1888), S. comatularum (Haswell, 1882), S. stimpsonii (de Man, 1888); Palaemonidae: Palaemonella pottsi (Borradaile, 1915), Pontoniopsis comanthi (Borradaile, 1915), one brachyuran crab [Pilumnidae: Permanotus purpureus (Gordon, 1934)] and one squat lobster [Galatheidae: Allogalathea elegans (Adams White, 1848)] were identified. The caridean shrimps have associated with the crinoids Comaster multifidus (Müller, 1841), Phanogenia gracilis (Hartlaub, 1893), P. distincta (Carpenter, 1888), P. multibrachiata (Carpenter, 1888) and Stephanometra indica (Smith, 1876). The brachyuran crab was observed in association with the crinoid Phanogenia gracilis whereas the squat lobsters were associated with Stephanometra tenuipinna (Hartlaub, 1890) and S. indica. Except S. stimpsonii and P. purpureus, all other species were recorded for the first time from India. Here, we provide details on morphology, distribution, habitat, and hosts for all species. We recommend further exploration of the sub-shallow coral reef areas of Lakshadweep as there will be many species that certainly remain to be discovered.},
}
@article {pmid33056527,
year = {2020},
author = {Neves, K},
title = {A new species of the shrimp genus Typton Costa, 1844 (Malacostraca, Decapoda, Palaemonidae) from the Cabo Verde Archipelago.},
journal = {Zootaxa},
volume = {4768},
number = {2},
pages = {zootaxa.4768.2.7},
doi = {10.11646/zootaxa.4768.2.7},
pmid = {33056527},
issn = {1175-5334},
mesh = {Animal Distribution ; Animal Structures ; Animals ; Cabo Verde ; *Decapoda ; *Palaemonidae ; },
abstract = {A new species of sponge-dwelling palaemonid shrimp of the genus Typton Costa, 1844 is described based on specimens collected in Enseada de Corais da Matiota, São Vicente Island, Cabo Verde. Typton anaramosae sp. nov., is the twentieth species known in this genus and is morphologically most similar to T. prionurus from the western Atlantic and T. granulosus and T. serratus from the eastern Pacific, all four sharing the serrated distal part of the outer margin of the uropodal exopod and the absence of a median tooth on the posterodorsal margin of the sixth pleonite. The more specific features, which distinguish the new species from its related congeners are discussed.},
}
@article {pmid33056380,
year = {2020},
author = {Schneider, SA and Lapolla, JS},
title = {Trophobiosis between a new species of Williamsrhizoecus (Hemiptera: Coccomorpha: Rhizoecidae) and Acropyga silvestrii (Hymenoptera: Formicidae) in Tanzania.},
journal = {Zootaxa},
volume = {4853},
number = {2},
pages = {zootaxa.4853.2.9},
doi = {10.11646/zootaxa.4853.2.9},
pmid = {33056380},
issn = {1175-5334},
mesh = {Animals ; *Ants ; *Hemiptera ; Symbiosis ; Tanzania ; },
abstract = {A new myrmecophilous species of root mealybug, Williamsrhizoecus udzungwensis sp. n., is described from individuals found living within a nest of Acropyga silvestrii in the Udzungwa Mountains of Tanzania. Acropyga ants are highly specialized, obligate associates of scale insects, typically members of the scale family Xenococcidae. Acropyga are best known for vertically transmitting trophobiotic partners during their nuptial flights and for housing them within brood chambers. This article presents the first record of trophobiosis between a species of Williamsrhizoecus and Acropyga, and only the second record of an association between Acropyga and rhizoecids in the Old World. This discovery contributes important information about the few species of Rhizoecidae confirmed to engage in these unique symbioses, each putatively the result of a past horizontal transmission event from a xenococcid to a rhizoecid lineage. Included is a discussion on the diagnosis of Williamsrhizoecus and an updated key to the species.},
}
@article {pmid33055756,
year = {2020},
author = {Anker, A and Al-Kandari, M and DE Grave, S},
title = {On two species of the alpheid shrimp genus Salmoneus Holthuis, 1955 from Kuwait, one of them new to science (Malacostraca: Decapoda: Caridea).},
journal = {Zootaxa},
volume = {4780},
number = {1},
pages = {zootaxa.4780.1.3},
doi = {10.11646/zootaxa.4780.1.3},
pmid = {33055756},
issn = {1175-5334},
mesh = {Animal Distribution ; Animal Structures ; Animals ; *Decapoda ; Kuwait ; },
abstract = {The alpheid genus Salmoneus Holthuis, 1955 is reported from Kuwait for the first time, with two species. One species, Salmoneus ikaros sp. nov., is described based on a single specimen from Failaka Island, extracted from the burrow of the callianassid ghost-shrimp Balsscallichirus masoomi (Tirmizi, 1970), together with the host. The new species is characterised by its peculiar eyes, which together with other characters separate it from all previously described species of Salmoneus. The second species, Salmoneus gracilipes Miya, 1972, is reported from Kuwait based on three specimens from two different localities and different habitats. Two specimens were found under coral rocks at a depth of about 7 m off Kubbar Island, whereas the third specimen was extracted from the burrow of the echiuran worm, Listriolobus cf. brevirostris Chen Yeh, 1958, at the type locality of S. ikaros sp. nov. at Failaka Island. Material identified as S. gracilipes from across its wide distribution range appears to be morphologically heterogeneous, possibly containing more than one species, and thus will need further studies.},
}
@article {pmid33053886,
year = {2020},
author = {Awais, M and Ghayvat, H and Krishnan Pandarathodiyil, A and Nabillah Ghani, WM and Ramanathan, A and Pandya, S and Walter, N and Saad, MN and Zain, RB and Faye, I},
title = {Healthcare Professional in the Loop (HPIL): Classification of Standard and Oral Cancer-Causing Anomalous Regions of Oral Cavity Using Textural Analysis Technique in Autofluorescence Imaging.},
journal = {Sensors (Basel, Switzerland)},
volume = {20},
number = {20},
pages = {},
pmid = {33053886},
issn = {1424-8220},
support = {Ministry of Education (MOE) Malaysia High Impact Research (HIR) Grant//UM.C/625/1/HIR/MOHE/DENT/06/ ; },
abstract = {Oral mucosal lesions (OML) and oral potentially malignant disorders (OPMDs) have been identified as having the potential to transform into oral squamous cell carcinoma (OSCC). This research focuses on the human-in-the-loop-system named Healthcare Professionals in the Loop (HPIL) to support diagnosis through an advanced machine learning procedure. HPIL is a novel system approach based on the textural pattern of OML and OPMDs (anomalous regions) to differentiate them from standard regions of the oral cavity by using autofluorescence imaging. An innovative method based on pre-processing, e.g., the Deriche-Canny edge detector and circular Hough transform (CHT); a post-processing textural analysis approach using the gray-level co-occurrence matrix (GLCM); and a feature selection algorithm (linear discriminant analysis (LDA)), followed by k-nearest neighbor (KNN) to classify OPMDs and the standard region, is proposed in this paper. The accuracy, sensitivity, and specificity in differentiating between standard and anomalous regions of the oral cavity are 83%, 85%, and 84%, respectively. The performance evaluation was plotted through the receiver operating characteristics of periodontist diagnosis with the HPIL system and without the system. This method of classifying OML and OPMD areas may help the dental specialist to identify anomalous regions for performing their biopsies more efficiently to predict the histological diagnosis of epithelial dysplasia.},
}
@article {pmid33053656,
year = {2020},
author = {Mayasari, NR and Ho, DKN and Lundy, DJ and Skalny, AV and Tinkov, AA and Teng, IC and Wu, MC and Faradina, A and Mohammed, AZM and Park, JM and Ngu, YJ and Aliné, S and Shofia, NM and Chang, JS},
title = {Impacts of the COVID-19 Pandemic on Food Security and Diet-Related Lifestyle Behaviors: An Analytical Study of Google Trends-Based Query Volumes.},
journal = {Nutrients},
volume = {12},
number = {10},
pages = {},
pmid = {33053656},
issn = {2072-6643},
support = {109TMU-TMUH-13//Taipei Medical University Hospital/ ; MOST109-2923-B-038-001-MY3//Ministry of Science and Technology, Taiwan/ ; MOST107-2320-B-038-010-MY3//Ministry of Science and Technology, Taiwan/ ; },
mesh = {Betacoronavirus ; COVID-19 ; Coronavirus ; *Coronavirus Infections/epidemiology/immunology/virology ; Curcuma ; *Diet ; Fatty Acids, Omega-3 ; *Feeding Behavior ; *Food Supply ; Garlic ; Health Behavior ; Humans ; Information Seeking Behavior ; *Life Style ; Nutrients ; *Pandemics ; *Pneumonia, Viral/epidemiology/immunology/virology ; Restaurants ; SARS-CoV-2 ; Search Engine ; Sedentary Behavior ; Severe Acute Respiratory Syndrome ; *Social Isolation ; Trace Elements ; Vitamins ; },
abstract = {The severe acute respiratory syndrome coronavirus (SARS-CoV)-2 disease (COVID)-19 is having profound effects on the global economy and food trade. Limited data are available on how this pandemic is affecting our dietary and lifestyle-related behaviors at the global level. Google Trends was used to obtain worldwide relative search volumes (RSVs) covering a timeframe from before the COVID-19 pandemic 1 June 2019 to 27 April 2020. Spearman's rank-order correlation coefficients were used to measure relationships between daily confirmed cases and aforementioned RSVs between 31 December 2019 and 15 April 2020. RSV curves showed increased interest in multiple keywords related to dietary and lifestyle behaviors during the COVID-19 lockdown period in March and April 2020. Spearman's correlation analysis showed that the strongest variables in each keyword category were (1) food security (food shortage: r = 0.749, food bank: r = 0.660, and free food: r = 0.555; all p < 0.001), (2) dietary behaviors (delivery: r = 0.780, restaurant: r = -0.731, take-away: r = 0.731, and food-delivery: r = 0.693; all p < 0.001), (3) outdoor-related behaviors (resort: r = -0.922, hotel: r = -0.913, cinema: r = -0.844, park: r = -0.827, fitness: r = -0.817, gym: r = -0.811; plant: r = 0.749, sunbathing: r = 0.668, and online: r = 0.670; all p < 0.001), and (4) immune-related nutrients/herbs/foods (vitamin C: r = 0.802, vitamin A: r = 0.780, zinc: r = 0.781, immune: r = 0.739, vitamin E: r = 0.707, garlic: r = 0.667, omega-3 fatty acid: r = -0.633, vitamin D: r = 0.549, and turmeric: r = 0.545; all p < 0.001). Restricted movement has affected peoples' dietary and lifestyle behaviors as people tend to search for immune-boosting nutrients/herbs and have replaced outdoor activities with sedentary indoor behaviors.},
}
@article {pmid33052936,
year = {2020},
author = {Ray, C and Rochefort, RM and Ransom, JI and Nesmith, JCB and Haultain, SA and Schaming, TD and Boetsch, JR and Holmgren, ML and Wilkerson, RL and Siegel, RB},
title = {Assessing trends and vulnerabilities in the mutualism between whitebark pine (Pinus albicaulis) and Clark's nutcracker (Nucifraga columbiana) in national parks of the Sierra-Cascade region.},
journal = {PloS one},
volume = {15},
number = {10},
pages = {e0227161},
pmid = {33052936},
issn = {1932-6203},
mesh = {Animals ; Bayes Theorem ; North America ; Parks, Recreational ; Passeriformes/*growth & development ; Pinus/*growth & development ; Population Density ; Population Dynamics ; Spatio-Temporal Analysis ; Symbiosis ; },
abstract = {Dispersal of whitebark pine (Pinus albicaulis Engelm.), a keystone species of many high-elevation ecosystems in western North America, depends on Clark's nutcracker (Nucifraga columbiana Wilson), a seed-caching bird with an affinity for whitebark seeds. To the extent that this dependence is mutual, declines in whitebark seed production could cause declines in nutcracker abundance. Whitebark pine is in decline across much of its range due to interacting stressors, including the non-native pathogen white pine blister rust (Cronartium ribicola J. C. Fisch.). We used avian point-count data and tree surveys from four national park units to investigate whether trends in whitebark pine can explain trends in Clark's nutcracker. Spatial trends were modeled using recent data from two parks, while temporal trends were modeled using longer time-series of nutcracker and whitebark data from two additional parks. To assess the potential dependence of nutcrackers on whitebark, we linked a model of nutcracker density (accounting for detection probability) with a model of whitebark trends, using a Bayesian framework to translate uncertainty in whitebark metrics to uncertainty in nutcracker density. In Mount Rainier National Park, temporal models showed dramatic declines in nutcracker density concurrent with significant increases in whitebark crown mortality and trees infected with white pine blister rust. However, nutcrackers did not trend with whitebark metrics in North Cascades National Park Service Complex. In spatial models of data from Yosemite National Park and Sequoia-Kings Canyon National Park, nutcracker density varied not only with local cover of whitebark but also with elevation and, in Sequoia-Kings Canyon, with cover of another species of white pine. Our results add support for the hypothesis that the mutualism between whitebark pine and Clark's nutcracker is vulnerable to disruption by blister rust, and our approach integrates data across monitoring programs to explore trends in species interactions.},
}
@article {pmid33051774,
year = {2020},
author = {Knudsen, L and Brandenberger, C and Ochs, M},
title = {Stereology as the 3D tool to quantitate lung architecture.},
journal = {Histochemistry and cell biology},
volume = {},
number = {},
pages = {},
doi = {10.1007/s00418-020-01927-0},
pmid = {33051774},
issn = {1432-119X},
abstract = {Stereology is the method of choice for the quantitative assessment of biological objects in microscopy. It takes into account the fact that, in traditional microscopy such as conventional light and transmission electron microscopy, although one has to rely on measurements on nearly two-dimensional sections from fixed and embedded tissue samples, the quantitative data obtained by these measurements should characterize the real three-dimensional properties of the biological objects and not just their "flatland" appearance on the sections. Thus, three-dimensionality is a built-in property of stereological sampling and measurement tools. Stereology is, therefore, perfectly suited to be combined with 3D imaging techniques which cover a wide range of complementary sample sizes and resolutions, e.g. micro-computed tomography, confocal microscopy and volume electron microscopy. Here, we review those stereological principles that are of particular relevance for 3D imaging and provide an overview of applications of 3D imaging-based stereology to the lung in health and disease. The symbiosis of stereology and 3D imaging thus provides the unique opportunity for unbiased and comprehensive quantitative characterization of the three-dimensional architecture of the lung from macro to nano scale.},
}
@article {pmid33050511,
year = {2020},
author = {Shelly, A and Gupta, P and Ahuja, R and Srichandan, S and Meena, J and Majumdar, T},
title = {Impact of Microbiota: A Paradigm for Evolving Herd Immunity against Viral Diseases.},
journal = {Viruses},
volume = {12},
number = {10},
pages = {},
pmid = {33050511},
issn = {1999-4915},
mesh = {Betacoronavirus/immunology ; COVID-19 ; Coronavirus Infections/epidemiology/immunology/microbiology/transmission ; Dysbiosis/immunology ; Humans ; *Immunity, Herd ; Immunity, Heterologous ; Immunity, Innate ; *Microbiota/immunology ; Pandemics ; Pneumonia, Viral/epidemiology/immunology/microbiology/transmission ; SARS-CoV-2 ; Vaccination ; Virus Diseases/epidemiology/*immunology/*microbiology/transmission ; },
abstract = {Herd immunity is the most critical and essential prophylactic intervention that delivers protection against infectious diseases at both the individual and community level. This process of natural vaccination is immensely pertinent to the current context of a pandemic caused by severe acute respiratory syndrome coronavirus-2 (SARS-CoV-2) infection around the globe. The conventional idea of herd immunity is based on efficient transmission of pathogens and developing natural immunity within a population. This is entirely encouraging while fighting against any disease in pandemic circumstances. A spatial community is occupied by people having variable resistance capacity against a pathogen. Protection efficacy against once very common diseases like smallpox, poliovirus or measles has been possible only because of either natural vaccination through contagious infections or expanded immunization programs among communities. This has led to achieving herd immunity in some cohorts. The microbiome plays an essential role in developing the body's immune cells for the emerging competent vaccination process, ensuring herd immunity. Frequency of interaction among microbiota, metabolic nutrients and individual immunity preserve the degree of vaccine effectiveness against several pathogens. Microbiome symbiosis regulates pathogen transmissibility and the success of vaccination among different age groups. Imbalance of nutrients perturbs microbiota and abrogates immunity. Thus, a particular population can become vulnerable to the infection. Intestinal dysbiosis leads to environmental enteropathy (EE). As a consequence, the generation of herd immunity can either be delayed or not start in a particular cohort. Moreover, disparities of the protective response of many vaccines in developing countries outside of developed countries are due to inconsistencies of healthy microbiota among the individuals. We suggested that pan-India poliovirus vaccination program, capable of inducing herd immunity among communities for the last 30 years, may also influence the inception of natural course of heterologous immunity against SARS-CoV-2 infection. Nonetheless, this anamnestic recall is somewhat counterintuitive, as antibody generation against original antigens of SARS-CoV-2 will be subdued due to original antigenic sin.},
}
@article {pmid33049039,
year = {2020},
author = {Santos-Garcia, D and Mestre-Rincon, N and Ouvrard, D and Zchori-Fein, E and Morin, S},
title = {Portiera Gets Wild: Genome Instability Provides Insights into the Evolution of Both Whiteflies and Their Endosymbionts.},
journal = {Genome biology and evolution},
volume = {12},
number = {11},
pages = {2107-2124},
doi = {10.1093/gbe/evaa216},
pmid = {33049039},
issn = {1759-6653},
abstract = {Whiteflies (Hemiptera: Sternorrhyncha: Aleyrodidae) are a superfamily of small phloem-feeding insects. They rely on their primary endosymbionts "Candidatus Portiera aleyrodidarum" to produce essential amino acids not present in their diet. Portiera has been codiverging with whiteflies since their origin and therefore reflects its host's evolutionary history. Like in most primary endosymbionts, the genome of Portiera stays stable across the Aleyrodidae superfamily after millions of years of codivergence. However, Portiera of the whitefly Bemisia tabaci has lost the ancestral genome order, reflecting a rare event in the endosymbiont evolution: the appearance of genome instability. To gain a better understanding of Portiera genome evolution, identify the time point in which genome instability appeared and contribute to the reconstruction of whitefly phylogeny, we developed a new phylogenetic framework. It targeted five Portiera genes and determined the presence of the DNA polymerase proofreading subunit (dnaQ) gene, previously associated with genome instability, and two alternative gene rearrangements. Our results indicated that Portiera gene sequences provide a robust tool for studying intergenera phylogenetic relationships in whiteflies. Using these new framework, we found that whitefly species from the Singhiella, Aleurolobus, and Bemisia genera form a monophyletic tribe, the Aleurolobini, and that their Portiera exhibit genome instability. This instability likely arose once in the common ancestor of the Aleurolobini tribe (at least 70 Ma), drawing a link between the appearance of genome instability in Portiera and the switch from multibacteriocyte to a single-bacteriocyte mode of inheritance in this tribe.},
}
@article {pmid33047414,
year = {2020},
author = {Stoy, KS and Gibson, AK and Gerardo, NM and Morran, LT},
title = {A need to consider the evolutionary genetics of host-symbiont mutualisms.},
journal = {Journal of evolutionary biology},
volume = {33},
number = {12},
pages = {1656-1668},
doi = {10.1111/jeb.13715},
pmid = {33047414},
issn = {1420-9101},
support = {2019-67013-29371//National Institute of Food and Agriculture/ ; DEB- 1754595//National Science Foundation/ ; DEB-1750553//National Science Foundation/ ; DGE-1444932//National Science Foundation/ ; },
abstract = {Despite the ubiquity and importance of mutualistic interactions, we know little about the evolutionary genetics underlying their long-term persistence. As in antagonistic interactions, mutualistic symbioses are characterized by substantial levels of phenotypic and genetic diversity. In contrast to antagonistic interactions, however, we, by and large, do not understand how this variation arises, how it is maintained, nor its implications for future evolutionary change. Currently, we rely on phenotypic models to address the persistence of mutualistic symbioses, but the success of an interaction almost certainly depends heavily on genetic interactions. In this review, we argue that evolutionary genetic models could provide a framework for understanding the causes and consequences of diversity and why selection may favour processes that maintain variation in mutualistic interactions.},
}
@article {pmid33046698,
year = {2020},
author = {Miyauchi, S and Kiss, E and Kuo, A and Drula, E and Kohler, A and Sánchez-García, M and Morin, E and Andreopoulos, B and Barry, KW and Bonito, G and Buée, M and Carver, A and Chen, C and Cichocki, N and Clum, A and Culley, D and Crous, PW and Fauchery, L and Girlanda, M and Hayes, RD and Kéri, Z and LaButti, K and Lipzen, A and Lombard, V and Magnuson, J and Maillard, F and Murat, C and Nolan, M and Ohm, RA and Pangilinan, J and Pereira, MF and Perotto, S and Peter, M and Pfister, S and Riley, R and Sitrit, Y and Stielow, JB and Szöllősi, G and Žifčáková, L and Štursová, M and Spatafora, JW and Tedersoo, L and Vaario, LM and Yamada, A and Yan, M and Wang, P and Xu, J and Bruns, T and Baldrian, P and Vilgalys, R and Dunand, C and Henrissat, B and Grigoriev, IV and Hibbett, D and Nagy, LG and Martin, FM},
title = {Large-scale genome sequencing of mycorrhizal fungi provides insights into the early evolution of symbiotic traits.},
journal = {Nature communications},
volume = {11},
number = {1},
pages = {5125},
pmid = {33046698},
issn = {2041-1723},
mesh = {Ecosystem ; Evolution, Molecular ; Fungal Proteins/genetics ; Fungi/classification/*genetics/physiology ; *Genome, Fungal ; Mycorrhizae/classification/*genetics/physiology ; Phylogeny ; Plant Physiological Phenomena ; Plants/microbiology ; *Symbiosis ; },
abstract = {Mycorrhizal fungi are mutualists that play crucial roles in nutrient acquisition in terrestrial ecosystems. Mycorrhizal symbioses arose repeatedly across multiple lineages of Mucoromycotina, Ascomycota, and Basidiomycota. Considerable variation exists in the capacity of mycorrhizal fungi to acquire carbon from soil organic matter. Here, we present a combined analysis of 135 fungal genomes from 73 saprotrophic, endophytic and pathogenic species, and 62 mycorrhizal species, including 29 new mycorrhizal genomes. This study samples ecologically dominant fungal guilds for which there were previously no symbiotic genomes available, including ectomycorrhizal Russulales, Thelephorales and Cantharellales. Our analyses show that transitions from saprotrophy to symbiosis involve (1) widespread losses of degrading enzymes acting on lignin and cellulose, (2) co-option of genes present in saprotrophic ancestors to fulfill new symbiotic functions, (3) diversification of novel, lineage-specific symbiosis-induced genes, (4) proliferation of transposable elements and (5) divergent genetic innovations underlying the convergent origins of the ectomycorrhizal guild.},
}
@article {pmid33043859,
year = {2020},
author = {Singh, A and Jha, A and Purbey, S},
title = {Identification of Measures Affecting Job Satisfaction and Levels of Perceived Stress and Burnout among Home Health Nurses of a Developing Asian Country.},
journal = {Hospital topics},
volume = {},
number = {},
pages = {1-11},
doi = {10.1080/00185868.2020.1830009},
pmid = {33043859},
issn = {1939-9278},
abstract = {BACKGROUND: Factors affecting job satisfaction of home health nurses are studied.
METHODS: PSS-10, CBI and HHNJS are used to measure the perceived stress, burnout of home health nurses and Job Satisfaction.
RESULTS: The significant predictors for Job satisfaction were Relationship with organization, Autonomy and control, Salary and Benefits as 82% of variation in job satisfaction was explained by these, (F change (3, 144) = 236.72, p < .001).
CONCLUSION: Agencies should work upon improving the dimensions such as the "relationship with the organization", "Autonomy and control" and "Salary and Benefits" to increases the Job satisfaction of home health nurses.},
}
@article {pmid33043803,
year = {2020},
author = {Robledo, M and García-Tomsig, NI and Matia-González, AM and García-Rodríguez, FM and Jiménez-Zurdo, JI},
title = {Synthetase of the methyl donor S-adenosylmethionine from nitrogen-fixing α-rhizobia can bind functionally diverse RNA species.},
journal = {RNA biology},
volume = {},
number = {},
pages = {1-13},
doi = {10.1080/15476286.2020.1829365},
pmid = {33043803},
issn = {1555-8584},
abstract = {Function of bacterial small non-coding RNAs (sRNAs) and overall RNA metabolism is largely shaped by a vast diversity of RNA-protein interactions. However, in non-model bacteria with defined non-coding transcriptomes the sRNA interactome remains almost unexplored. We used affinity chromatography to capture proteins associated in vivo with MS2-tagged trans-sRNAs that regulate nutrient uptake (AbcR2 and NfeR1) and cell cycle (EcpR1) mRNAs by antisense-based translational inhibition in the nitrogen-fixing α-rhizobia Sinorhizobium meliloti. The three proteomes were rather distinct, with that of EcpR1 particularly enriched in cell cycle-related enzymes, whilst sharing several transcription/translation-related proteins recurrently identified associated with sRNAs. Strikingly, MetK, the synthetase of the major methyl donor S-adenosylmethionine, was reliably recovered as a binding partner of the three sRNAs, which reciprocally co-immunoprecipitated with a FLAG-tagged MetK variant. Induced (over)expression of the trans-sRNAs and MetK depletion did not influence canonical riboregulatory traits, `for example, protein titration or sRNA stability, respectively. An in vitro filter assay confirmed binding of AbcR2, NfeR1 and EcpR1 to MetK and further revealed interaction of the protein with other non-coding and coding transcripts but not with the 5S rRNA. These findings uncover a broad specificity for RNA binding as an unprecedented feature of this housekeeping prokaryotic enzyme.},
}
@article {pmid33043410,
year = {2020},
author = {Vohník, M},
title = {Ericoid mycorrhizal symbiosis: theoretical background and methods for its comprehensive investigation.},
journal = {Mycorrhiza},
volume = {30},
number = {6},
pages = {671-695},
doi = {10.1007/s00572-020-00989-1},
pmid = {33043410},
issn = {1432-1890},
support = {GAČR 18-05886S//Czech Science Foundation/ ; RVO 67985939//Czech Academy of Sciences/ ; },
mesh = {*Ericaceae ; *Mycorrhizae ; Plant Roots ; Plants ; Symbiosis ; },
abstract = {Despite decades of intensive research (especially from 1970s to 1990s), the ericoid mycorrhizal (ErM) hair root is still largely terra incognita and this simplified guide is intended to revive and promote the study of its mycobiota. Basic theoretical knowledge on the ErM symbiosis is summarized, followed by practical advices on Ericaceae root sample collection and handling, microscopic observations and photo-documentation of root fungal colonization, mycobiont isolation, maintenance and identification and resynthesis experiments with ericoid plants. The necessity of a proper selection of the root material and its surface sterilization prior to mycobiont isolation is stressed, together with the need of including suitable control treatments in inoculation experiments. The culture-dependent approach employing plating of single short (~ 2 mm) hair root segments on nutrient media is substantiated as a useful tool for characterization of Ericaceae root-associated fungal communities; it targets living mycelium and provides metabolically active cultures that can be used in physiological experiments and taxonomic studies, thus providing essential reference material for culture-independent approaches. On the other hand, it is stressed that not every mycobiont isolated from an ericoid hair root necessarily represent an ErM fungus. Likewise, not every intracellular hyphal coil formed in the Ericaceae rhizodermis necessarily represents the ErM symbiosis. Taxonomy of the most important ericoid mycobionts is updated, mutualism in the ErM symbiosis is briefly discussed from the mycobiont perspective, and some interesting lines of possible future research are highlighted.},
}
@article {pmid33042514,
year = {2020},
author = {Roux, N and Salis, P and Lee, SH and Besseau, L and Laudet, V},
title = {Anemonefish, a model for Eco-Evo-Devo.},
journal = {EvoDevo},
volume = {11},
number = {},
pages = {20},
pmid = {33042514},
issn = {2041-9139},
abstract = {Anemonefish, are a group of about 30 species of damselfish (Pomacentridae) that have long aroused the interest of coral reef fish ecologists. Combining a series of original biological traits and practical features in their breeding that are described in this paper, anemonefish are now emerging as an experimental system of interest for developmental biology, ecology and evolutionary sciences. They are small sized and relatively easy to breed in specific husbandries, unlike the large-sized marine fish used for aquaculture. Because they live in highly structured social groups in sea anemones, anemonefish allow addressing a series of relevant scientific questions such as the social control of growth and sex change, the mechanisms controlling symbiosis, the establishment and variation of complex color patterns, and the regulation of aging. Combined with the use of behavioral experiments, that can be performed in the lab or directly in the wild, as well as functional genetics and genomics, anemonefish provide an attractive experimental system for Eco-Evo-Devo.},
}
@article {pmid33042042,
year = {2020},
author = {Sharma, MP and Grover, M and Chourasiya, D and Bharti, A and Agnihotri, R and Maheshwari, HS and Pareek, A and Buyer, JS and Sharma, SK and Schütz, L and Mathimaran, N and Singla-Pareek, SL and Grossman, JM and Bagyaraj, DJ},
title = {Deciphering the Role of Trehalose in Tripartite Symbiosis Among Rhizobia, Arbuscular Mycorrhizal Fungi, and Legumes for Enhancing Abiotic Stress Tolerance in Crop Plants.},
journal = {Frontiers in microbiology},
volume = {11},
number = {},
pages = {509919},
pmid = {33042042},
issn = {1664-302X},
abstract = {Drought is a critical factor limiting the productivity of legumes worldwide. Legumes can enter into a unique tripartite symbiotic relationship with root-nodulating bacteria of genera Rhizobium, Bradyrhizobium, or Sinorhizobium and colonization by arbuscular mycorrhizal fungi (AMF). Rhizobial symbiosis provides nitrogen necessary for growth. AMF symbiosis enhances uptake of diffusion-limited nutrients such as P, Zn, Cu, etc., and also water from the soil via plant-associated fungal hyphae. Rhizobial and AMF symbioses can act synergistically in promoting plant growth and fitness, resulting in overall yield benefits under drought stress. One of the approaches that rhizobia use to survive under stress is the accumulation of compatible solutes, or osmolytes, such as trehalose. Trehalose is a non-reducing disaccharide and an osmolyte reported to accumulate in a range of organisms. High accumulation of trehalose in bacteroids during nodulation protects cells and proteins from osmotic shock, desiccation, and heat under drought stress. Manipulation of trehalose cell concentrations has been directly correlated with stress response in plants and other organisms, including AMF. However, the role of this compound in the tripartite symbiotic relationship is not fully explored. This review describes the biological importance and the role of trehalose in the tripartite symbiosis between plants, rhizobia, and AMF. In particular, we review the physiological functions and the molecular investigations of trehalose carried out using omics-based approaches. This review will pave the way for future studies investigating possible metabolic engineering of this biomolecule for enhancing abiotic stress tolerance in plants.},
}
@article {pmid33041180,
year = {2020},
author = {Rosset, SL and Oakley, CA and Ferrier-Pagès, C and Suggett, DJ and Weis, VM and Davy, SK},
title = {The Molecular Language of the Cnidarian-Dinoflagellate Symbiosis.},
journal = {Trends in microbiology},
volume = {},
number = {},
pages = {},
doi = {10.1016/j.tim.2020.08.005},
pmid = {33041180},
issn = {1878-4380},
abstract = {The cnidarian-dinoflagellate symbiosis is of huge importance as it underpins the success of coral reefs, yet we know very little about how the host cnidarian and its dinoflagellate endosymbionts communicate with each other to form a functionally integrated unit. Here, we review the current knowledge of interpartner molecular signaling in this symbiosis, with an emphasis on lipids, glycans, reactive species, biogenic volatiles, and noncoding RNA. We draw upon evidence of these compounds from recent omics-based studies of cnidarian-dinoflagellate symbiosis and discuss the signaling roles that they play in other, better-studied symbioses. We then consider how improved knowledge of interpartner signaling might be used to develop solutions to the coral reef crisis by, for example, engineering more thermally resistant corals.},
}
@article {pmid33040738,
year = {2020},
author = {Brown, JJ and Rodríguez-Ruano, SM and Poosakkannu, A and Batani, G and Schmidt, JO and Roachell, W and Zima, J and Hypša, V and Nováková, E},
title = {Ontogeny, species identity, and environment dominate microbiome dynamics in wild populations of kissing bugs (Triatominae).},
journal = {Microbiome},
volume = {8},
number = {1},
pages = {146},
pmid = {33040738},
issn = {2049-2618},
abstract = {BACKGROUND: Kissing bugs (Triatominae) are blood-feeding insects best known as the vectors of Trypanosoma cruzi, the causative agent of Chagas' disease. Considering the high epidemiological relevance of these vectors, their biology and bacterial symbiosis remains surprisingly understudied. While previous investigations revealed generally low individual complexity but high among-individual variability of the triatomine microbiomes, any consistent microbiome determinants have not yet been identified across multiple Triatominae species.
METHODS: To obtain a more comprehensive view of triatomine microbiomes, we investigated the host-microbiome relationship of five Triatoma species sampled from white-throated woodrat (Neotoma albigula) nests in multiple locations across the USA. We applied optimised 16S rRNA gene metabarcoding with a novel 18S rRNA gene blocking primer to a set of 170 T. cruzi-negative individuals across all six instars.
RESULTS: Triatomine gut microbiome composition is strongly influenced by three principal factors: ontogeny, species identity, and the environment. The microbiomes are characterised by significant loss in bacterial diversity throughout ontogenetic development. First instars possess the highest bacterial diversity while adult microbiomes are routinely dominated by a single taxon. Primarily, the bacterial genus Dietzia dominates late-stage nymphs and adults of T. rubida, T. protracta, and T. lecticularia but is not present in the phylogenetically more distant T. gerstaeckeri and T. sanguisuga. Species-specific microbiome composition, particularly pronounced in early instars, is further modulated by locality-specific effects. In addition, pathogenic bacteria of the genus Bartonella, acquired from the vertebrate hosts, are an abundant component of Triatoma microbiomes.
CONCLUSION: Our study is the first to demonstrate deterministic patterns in microbiome composition among all life stages and multiple Triatoma species. We hypothesise that triatomine microbiome assemblages are produced by species- and life stage-dependent uptake of environmental bacteria and multiple indirect transmission strategies that promote bacterial transfer between individuals. Altogether, our study highlights the complexity of Triatominae symbiosis with bacteria and warrant further investigation to understand microbiome function in these important vectors. Video abstract.},
}
@article {pmid33040612,
year = {2020},
author = {Chaturvedi, R and Favas, PJC and Pratas, J and Varun, M and Paul, MS},
title = {Harnessing Pisum sativum-Glomus mosseae symbiosis for phytoremediation of soil contaminated with lead, cadmium, and arsenic.},
journal = {International journal of phytoremediation},
volume = {},
number = {},
pages = {1-12},
doi = {10.1080/15226514.2020.1812507},
pmid = {33040612},
issn = {1549-7879},
abstract = {This study investigates the impact of Glomus mosseae on heavy metal(loid) (HM) uptake efficiency of pea (Pisum sativum L.) plants along with physiological and biochemical parameters. Plants were grown in soil spiked with HMs (Pb and As: 50 and 100 mg kg-1; Cd: 25 and 50 mg kg-1) and a multi-metal(loid) (Mm: Pb + Cd + As) combination, inoculated/non-inoculated with G. mosseae. A dose-dependent increase in HM accumulation was observed in plants upon harvest at 60 days. Plant growth, concentration of photosynthetic pigments, total nitrogen, and carbohydrates reduced, whereas enzymatic [catalase (CAT), superoxide dismutase (SOD), and ascorbate peroxidase (APX)] and non-enzymatic (proline and total phenolics) antioxidants increased upon HM stress. Inoculation with G. mosseae led to an increase in plant growth, concentration of photosynthetic pigments, carbohydrate, nitrogen, and defence antioxidants (whereas proline decreased) which was statistically significant (p ≤ 0.05). This symbiosis can be applied for onsite remediation of Pb and Cd contaminated soil by virtue of accumulation efficiency and adaptive response of pea plants inoculated with G. mosseae. Since the amount of HMs in edible parts exceeded the maximum permissible limits recommended by FAO/WHO, pea must not be cultivated in HM-contaminated soil for agricultural purpose due to associated toxicity. Novelty statement To our knowledge, phytoremediation potential of Pea in synchronization with Glomus mosseae has not been evaluated previously. This study highlights: • Pea-AMF symbiosis can be applied for Pb and/or Cd phytoremediation. • Target Hazard Quotient >1 for Pb, Cd and As; caution to food chain exposure required. • Nonenzymatic (proline, TPC) and enzymatic (CAT, SOD, APX) antioxidants play a key role in ROS detoxification.},
}
@article {pmid33038621,
year = {2020},
author = {Wang, J and Lei, Z and Wei, Y and Wang, Q and Tian, C and Shimizu, K and Zhang, Z and Adachi, Y and Lee, DJ},
title = {Behavior of algal-bacterial granular sludge in a novel closed photo-sequencing batch reactor under no external O2 supply.},
journal = {Bioresource technology},
volume = {318},
number = {},
pages = {124190},
doi = {10.1016/j.biortech.2020.124190},
pmid = {33038621},
issn = {1873-2976},
mesh = {Aerobiosis ; Bacteria ; *Bioreactors ; Extracellular Polymeric Substance Matrix ; Nitrogen ; Phosphorus ; *Sewage ; Waste Disposal, Fluid ; },
abstract = {Algal-bacterial aerobic granular sludge (AB-AGS) as a symbiosis system possesses high potential for being operated without external O2 supply. In this study, a novel lab-scale closed photo-sequencing batch reactor (PSBR) was developed for AB-AGS operation under successively open (Phase Ⅰ) and closed (Phase Ⅱ) conditions. Results show that AB-AGS maintained almost 100% of organics removal, exhibiting higher removals of phosphate (63 ± 20%), K+ (19 ± 12%) and Mg2+ (26 ± 12%), and higher chlorophylls content during Phase II. Meanwhile, only O2 besides N2 was detectable in the headspace of PSBR. The change of granular structure and faster algae growth during Phase Ⅱ may contribute to the increase of microbial activity and phosphorus bioavailability, in which lower extracellular polymeric substances content may account for low biomass retention. Results from this closed PSBR imply that AB-AGS has the potential to reduce some greenhouse gases like CO2 and CH4 emission.},
}
@article {pmid33038511,
year = {2021},
author = {Scardaci, R and Varese, F and Manfredi, M and Marengo, E and Mazzoli, R and Pessione, E},
title = {Enterococcus faecium NCIMB10415 responds to norepinephrine by altering protein profiles and phenotypic characters.},
journal = {Journal of proteomics},
volume = {231},
number = {},
pages = {104003},
doi = {10.1016/j.jprot.2020.104003},
pmid = {33038511},
issn = {1876-7737},
abstract = {The long-term established symbiosis between gut microbiota and humans is based upon a dynamic equilibrium that, if unbalanced, could lead to the development of diseases. Despite the huge amount of data concerning the microbiota-gut-brain-axis, little information is available on what happens at the molecular level in bacteria, when exposed to human signals. In the present study, the physiological effects exerted by norepinephrine (NE), a human hormone present in significant amounts in the host gut, were analyzed using the commensal/probiotic strain Enterococcus faecium NCIMB10415 as a target. The aim was to compare the protein profiles of treated and untreated bacteria and relating these proteome patterns to some phenotypic modifications important for bacteria-host interaction. Actually, to date, only pathogens have been considered. Combining a gel-free/label-free proteomic analysis with the evaluation of bile salts resistance, biofilm formation and autoaggregation ability (as well as with the bacterial growth kinetics), allowed to detect changes induced by NE treatment on all the tested probiotic properties. Furthermore, exposure to the bioactive molecule increased the abundance of proteins related to stress response and to host-microbe interaction, such as moonlight proteins involved in adhesion and immune stimulation. The results of this investigation demonstrated that, not only pathogens, but also commensal gut bacteria are affected by host-derived hormones, underlining the importance of a correct cross-signalling in the maintenance of gut homeostasis. SIGNIFICANCE: The crucial role played by the human gut microbiota in ensuring host homeostasis and health is definitively ascertained as suggested by the holobiome concept. The present research was intended to shed light on the endocrinological perturbations possibly affecting microbiota. The microbial model used in this study belongs to Enterococcus faecium species, whose controversial role as gut commensal and opportunistic pathogen in the gut ecosystem is well recognized. The results obtained in the present investigation clearly demonstrate that E. faecium NCIMB10415 can sense and respond to norepinephrine, a human hormone abundant at the gut level, by changing protein profiles and physiology, inducing changes that could favor survival and colonization of the host tissues. To our knowledge, this is the first proteomic report concerning the impact of a human hormone on a commensal/probiotic bacterium, since previous research has focused on exploring the effects of neuroendocrine molecules on growth and virulence of pathogenic species.},
}
@article {pmid33032576,
year = {2020},
author = {Diller, M and Johnson, E and Hicks, A and Hogan, WR},
title = {A realism-based approach to an ontological representation of symbiotic interactions.},
journal = {BMC medical informatics and decision making},
volume = {20},
number = {1},
pages = {258},
pmid = {33032576},
issn = {1472-6947},
support = {U24 GM110707/GM/NIGMS NIH HHS/United States ; R01 GM101151/GM/NIGMS NIH HHS/United States ; UL1 TR001427/TR/NCATS NIH HHS/United States ; },
abstract = {BACKGROUND: The symbiotic interactions that occur between humans and organisms in our environment have a tremendous impact on our health. Recently, there has been a surge in interest in understanding the complex relationships between the microbiome and human health and host immunity against microbial pathogens, among other things. To collect and manage data about these interactions and their complexity, scientists will need ontologies that represent symbiotic interactions as they occur in reality.
METHODS: We began with two papers that reviewed the usage of 'symbiosis' and related terms in the biology and ecology literature and prominent textbooks. We then analyzed several prominent standard terminologies and ontologies that contain representations of symbiotic interactions, to determine if they appropriately defined 'symbiosis' and related terms according to current scientific usage as identified by the review papers. In the process, we identified several subtypes of symbiotic interactions, as well as the characteristics that differentiate them, which we used to propose textual and axiomatic definitions for each subtype of interaction. To both illustrate how to use the ontological representations and definitions we created and provide additional quality assurance on key definitions, we carried out a referent tracking analysis and representation of three scenarios involving symbiotic interactions among organisms.
RESULTS: We found one definition of 'symbiosis' in an existing ontology that was consistent with the vast preponderance of scientific usage in biology and ecology. However, that ontology changed its definition during the course of our work, and discussions are ongoing. We present a new definition that we have proposed. We also define 34 subtypes of symbiosis. Our referent tracking analysis showed that it is necessary to define symbiotic interactions at the level of the individual, rather than at the species level, due to the complex nature in which organisms can go from participating in one type of symbiosis with one organism to participating in another type of symbiosis with a different organism.
CONCLUSION: As a result of our efforts here, we have developed a robust representation of symbiotic interactions using a realism-based approach, which fills a gap in existing biomedical ontologies.},
}
@article {pmid33031424,
year = {2020},
author = {Zhang, WD and Yao, WL and He, WH and Li, JF and Wu, XP and Chen, ZH and Liu, L and Wang, WH},
title = {Bacterial community analysis on the different mucosal immune inductive sites of gastrointestinal tract in Bactrian camels.},
journal = {PloS one},
volume = {15},
number = {10},
pages = {e0239987},
pmid = {33031424},
issn = {1932-6203},
mesh = {Animals ; Bacteria/genetics/isolation & purification ; Bacteroidetes/genetics/isolation & purification ; Biodiversity ; Camelus ; Fibrobacter/genetics/isolation & purification ; Gastrointestinal Tract/*microbiology ; High-Throughput Nucleotide Sequencing ; *Immunity, Mucosal ; Lymphoid Tissue/immunology/*microbiology ; *Microbiota ; Principal Component Analysis ; RNA, Ribosomal, 16S/chemistry/metabolism ; Symbiosis ; },
abstract = {The microbial communities colonize the mucosal immune inductive sites could be captured by hosts, which could initiate the mucosal immune responses. The aggregated lymphoid nodule area (ALNA) and the ileal Payer's patches (PPs) in Bactrian camels are both the mucosal immune inductive sites of the gastrointestinal tract. Here, the bacteria community associated with the ALNA and ileal PPs were analyzed using of 16S rDNA-Illumina Miseq sequencing. The mutual dominant bacterial phyla at the two sites were the Bacteroidetes, Firmicutes, Verrucomicrobia and Proteobacteria, and the mutual dominant genus in both sits was Prevotella. The abundances of the Fibrobacter, Campylobacter and RFP12 were all higher in ALNA than in ileal PPs. While, the abundances of the 5-7N15, Clostridium, and Escherichia were all higher in ileal PPs than in ALNA. The results suggested that the host's intestinal microenvironment is selective for the symbiotic bacteria colonizing the corresponding sites, on the contrary, the symbiotic bacteria could impact on the physiological functions of this local site. In ALNA and ileal PPs of Bactrian camel, the bacteria which colonized different immune inductive sites have the potential to stimulate different immune responses, which is the result of the mutual selection and adaptation between microbial communities and their host.},
}
@article {pmid33029783,
year = {2020},
author = {Franklin, JB and Hockey, K and Maherali, H},
title = {Population-level variation in host plant response to multiple microbial mutualists.},
journal = {American journal of botany},
volume = {107},
number = {10},
pages = {1389-1400},
doi = {10.1002/ajb2.1543},
pmid = {33029783},
issn = {1537-2197},
mesh = {*Medicago truncatula ; *Mycorrhizae ; Plant Roots ; *Rhizobium ; Symbiosis ; },
abstract = {PREMISE: Multipartite mutualisms are widespread in nature, but population-level variation in these interactions is rarely quantified. In the model multipartite mutualism between legumes, arbuscular mycorrhizal (AM) fungi and rhizobia bacteria, host responses to microbial partners are expected to be synergistic because the nutrients provided by each microbe colimit plant growth, but tests of this prediction have not been done in multiple host populations.
METHODS: To test whether plant response to associations with AM fungi and rhizobia varies among host populations and whether synergistic responses to microbial mutualists are common, we grew 34 Medicago truncatula populations in a factorial experiment that manipulated the presence or absence of each mutualist.
RESULTS: Plant growth increased in response to each mutualist, but there were no synergistic effects. Instead, plant response to inoculation with AM fungi was an order of magnitude higher than with rhizobia. Plant response to AM fungi varied among populations, whereas responses to rhizobia were relatively uniform. There was a positive correlation between plant host response to each mutualist but no correlation between AM fungal colonization and rhizobia nodulation of plant roots.
CONCLUSIONS: The greater population divergence in host response to AM fungi relative to rhizobia, weak correlation in host response to each microbial mutualist, and the absence of a correlation between measures of AM fungal and rhizobia performance suggests that each plant-microbe mutualism evolved independently among M. truncatula populations.},
}
@article {pmid33029225,
year = {2020},
author = {Mansour, S and Swanson, E and Pesce, C and Simpson, S and Morris, K and Thomas, WK and Tisa, LS},
title = {Draft Genome Sequences for the Frankia sp. strains CgS1, CcI156 and CgMI4, Nitrogen-Fixing Bacteria Isolated from Casuarina sp. in Egypt.},
journal = {Journal of genomics},
volume = {8},
number = {},
pages = {84-88},
pmid = {33029225},
issn = {1839-9940},
abstract = {Frankia sp. strains CgS1, CcI156 and CgMI4 were isolated from Casuarina glauca and C. cunninghamiana nodules. Here, we report the 5.26-, 5.33- and 5.20-Mbp draft genome sequences of Frankia sp. strains CgS1, CcI156 and CgMI4, respectively. Analysis of the genome revealed the presence of high numbers of secondary metabolic biosynthetic gene clusters.},
}
@article {pmid33028894,
year = {2020},
author = {Horák, A and Allen, AE and Oborník, M},
title = {Common origin of ornithine-urea cycle in opisthokonts and stramenopiles.},
journal = {Scientific reports},
volume = {10},
number = {1},
pages = {16687},
pmid = {33028894},
issn = {2045-2322},
mesh = {Animals ; Biological Evolution ; Databases, Genetic ; Ornithine/*metabolism ; Phylogeny ; Stramenopiles/*metabolism ; Symbiosis/physiology ; Urea/*metabolism ; },
abstract = {Eukaryotic complex phototrophs exhibit a colorful evolutionary history. At least three independent endosymbiotic events accompanied by the gene transfer from the endosymbiont to host assembled a complex genomic mosaic. Resulting patchwork may give rise to unique metabolic capabilities; on the other hand, it can also blur the reconstruction of phylogenetic relationships. The ornithine-urea cycle (OUC) belongs to the cornerstone of the metabolism of metazoans and, as found recently, also photosynthetic stramenopiles. We have analyzed the distribution and phylogenetic positions of genes encoding enzymes of the urea synthesis pathway in eukaryotes. We show here that metazoan and stramenopile OUC enzymes share common origins and that enzymes of the OUC found in primary algae (including plants) display different origins. The impact of this fact on the evolution of stramenopiles is discussed here.},
}
@article {pmid33028252,
year = {2020},
author = {Jeon, YJ and Gil, CH and Won, J and Jo, A and Kim, HJ},
title = {Symbiotic microbiome Staphylococcus aureus from human nasal mucus modulates IL-33-mediated type 2 immune responses in allergic nasal mucosa.},
journal = {BMC microbiology},
volume = {20},
number = {1},
pages = {301},
pmid = {33028252},
issn = {1471-2180},
abstract = {BACKGROUND: The host-microbial commensalism can shape the innate immune responses in respiratory mucosa and nasal microbiome also modulates front-line immune mechanism in the nasal mucosa. Inhaled allergens encounter the host immune system first in the nasal mucosa, and microbial characteristics of nasal mucus directly impact the mechanisms of initial allergic responses in nasal epithelium. However, the roles of the nasal microbiome in allergic nasal mucosa remain uncertain. We sought to determine the distribution of nasal microbiomes in allergic nasal mucosa and elucidate the interplay between nasal microbiome Staphylococcus species and Th2 cytokines in allergic rhinitis (AR) models.
RESULTS: Staphylococcus aureus (AR-SA) and S. epidermidis (AR-SE) were isolated from the nasal mucosa of patients with AR. The influence of nasal microbiome Staphylococcus species on allergic nasal mucosa was also tested with in vitro and in vivo AR models. Pyrosequencing data showed that colonization by S. epidermidis and S. aureus was more dominant in nasal mucus of AR subjects. The mRNA and protein levels of IL-33 and TSLP were significantly higher in AR nasal epithelial (ARNE) cells which were cultured from nasal mucosa of AR subjects, and exposure of ARNE cells to AR-SA reduced IL-33 mRNA and secreted protein levels. Particularly, ovalbumin-driven AR mice inoculated with AR-SA by intranasal delivery exhibited significantly reduced IL-33 in their nasal mucosa. In the context of these results, allergic symptoms and Th2 cytokine levels were significantly downregulated after intranasal inoculation of AR-SA in vivo AR mice.
CONCLUSION: Colonization by Staphylococcus species was more dominant in allergic nasal mucosa, and nasal commensal S. aureus from subjects with AR mediates anti-allergic effects by modulating IL-33-dependent Th2 inflammation. The results demonstrate the role of host-bacterial commensalism in shaping human allergic inflammation.},
}
@article {pmid33025575,
year = {2020},
author = {Clowez, S and Renicke, C and Pringle, JR and Grossman, AR},
title = {Impact of menthol on growth and photosynthetic function of Breviolum minutum (Dinoflagellata, Dinophyceae, Symbiodiniaceae) and interactions with its Aiptasia host.},
journal = {Journal of phycology},
volume = {},
number = {},
pages = {},
doi = {10.1111/jpy.13081},
pmid = {33025575},
issn = {1529-8817},
abstract = {Environmental change, including global warming and chemical pollution, can compromise cnidarian (e.g., coral) -dinoflagellate symbioses and cause coral bleaching. Understanding the mechanisms that regulate these symbioses will inform strategies for sustaining healthy coral-reef communities. A model system for corals is the symbiosis between the sea anemone Exaiptasia pallida (common name Aiptasia) and its dinoflagellate partners (family Symbiodiniaceae). To complement existing studies of the interactions between these organisms, we examined the impact of menthol, a reagent often used to render cnidarians aposymbiotic, on the dinoflagellate Breviolum minutum, both in culture and in hospite. In both environments, the growth and photosynthesis of this alga were compromised at either 100 or 300 µM menthol. We observed reduction of PSII and PSI functions, the abundances of reaction-center proteins, and, at 300 µM menthol, of total cellular proteins. Interestingly, for free-living algae exposed to 100 µM menthol, an initial decline in growth, photosynthetic activities, pigmentation, and protein abundances reversed after 5-15 d, eventually approaching control levels. This behavior was observed in cells maintained in continuous light, but not in cells experiencing a light-dark regimen, suggesting that B. minutum can detoxify menthol or acclimate and repair damaged photosynthetic complexes in a light- and/or energy-dependent manner. Extended exposures of cultured algae to 300 µM menthol ultimately resulted in algal death. Most symbiotic anemones were also unable to survive this menthol concentration for 30 d. Additionally, cells impaired for photosynthesis by pre-treatment with 300 µM menthol exhibited reduced efficiency in re-populating the anemone host.},
}
@article {pmid33024226,
year = {2020},
author = {Majumder, R and Sutcliffe, B and Taylor, PW and Chapman, TA},
title = {Fruit host-dependent fungal communities in the microbiome of wild Queensland fruit fly larvae.},
journal = {Scientific reports},
volume = {10},
number = {1},
pages = {16550},
pmid = {33024226},
issn = {2045-2322},
abstract = {Bactrocera tryoni (Froggatt), the Queensland fruit fly (Qfly), is a highly polyphagous tephritid fly that is widespread in Eastern Australia. Qfly physiology is closely linked with its fungal associates, with particular relationship between Qfly nutrition and yeast or yeast-like fungi. Despite animal-associated fungi typically occurring in multi-species communities, Qfly studies have predominately involved the culture and characterisation of single fungal isolates. Further, only two studies have investigated the fungal communities associated with Qfly, and both have used culture-dependant techniques that overlook non-culturable fungi and hence under-represent, and provide a biased interpretation of, the overall fungal community. In order to explore a potentially hidden fungal diversity and complexity within the Qfly mycobiome, we used culture-independent, high-throughput Illumina sequencing techniques to comprehensively, and holistically characterized the fungal community of Qfly larvae and overcome the culture bias. We collected larvae from a range of fruit hosts along the east coast of Australia, and all had a mycobiome dominated by ascomycetes. The most abundant fungal taxa belonged to the genera Pichia (43%), Candida (20%), Hanseniaspora (10%), Zygosaccharomyces (11%) and Penicillium (7%). We also characterized the fungal communities of fruit hosts, and found a strong degree of overlap between larvae and fruit host communities, suggesting that these communities are intimately inter-connected. Our data suggests that larval fungal communities are acquired from surrounding fruit flesh. It is likely that the physiological benefits of Qfly exposure to fungal communities is primarily due to consumption of these fungi, not through syntrophy/symbiosis between fungi and insect 'host'.},
}
@article {pmid33024051,
year = {2020},
author = {Motoki, K and Watsuji, TO and Takaki, Y and Takai, K and Iwasaki, W},
title = {Metatranscriptomics by In Situ RNA Stabilization Directly and Comprehensively Revealed Episymbiotic Microbial Communities of Deep-Sea Squat Lobsters.},
journal = {mSystems},
volume = {5},
number = {5},
pages = {},
pmid = {33024051},
issn = {2379-5077},
abstract = {Shinkaia crosnieri is an invertebrate that inhabits an area around deep-sea hydrothermal vents in the Okinawa Trough in Japan by harboring episymbiotic microbes as the primary nutrition. To reveal physiology and phylogenetic composition of the active episymbiotic populations, metatranscriptomics is expected to be a powerful approach. However, this has been hindered by substantial perturbation (e.g., RNA degradation) during time-consuming retrieval from the deep sea. Here, we conducted direct metatranscriptomic analysis of S. crosnieri episymbionts by applying in situ RNA stabilization equipment. As expected, we obtained RNA expression profiles that were substantially different from those obtained by conventional metatranscriptomics (i.e., stabilization after retrieval). The episymbiotic community members were dominated by three orders, namely, Thiotrichales, Methylococcales, and Campylobacterales, and the Campylobacterales members were mostly dominated by the Sulfurovum genus. At a finer phylogenetic scale, the episymbiotic communities on different host individuals shared many species, indicating that the episymbionts on each host individual are not descendants of a few founder cells but are horizontally exchanged. Furthermore, our analysis revealed the key metabolisms of the community: two carbon fixation pathways, a formaldehyde assimilation pathway, and utilization of five electron donors (sulfide, thiosulfate, sulfur, methane, and ammonia) and two electron accepters (oxygen and nitrate/nitrite). Importantly, it was suggested that Thiotrichales episymbionts can utilize intercellular sulfur globules even when sulfur compounds are not usable, possibly also in a detached and free-living state.IMPORTANCE Deep-sea hydrothermal vent ecosystems remain mysterious. To depict in detail the enigmatic life of chemosynthetic microbes, which are key primary producers in these ecosystems, metatranscriptomic analysis is expected to be a promising approach. However, this has been hindered by substantial perturbation (e.g., RNA degradation) during time-consuming retrieval from the deep sea. In this study, we conducted direct metatranscriptome analysis of microbial episymbionts of deep-sea squat lobsters (Shinkaia crosnieri) by applying in situ RNA stabilization equipment. Compared to conventional metatranscriptomics (i.e., RNA stabilization after retrieval), our method provided substantially different RNA expression profiles. Moreover, we discovered that S. crosnieri and its episymbiotic microbes constitute complex and resilient ecosystems, where closely related but various episymbionts are stably maintained by horizontal exchange and partly by their sulfur storage ability for survival even when sulfur compounds are not usable, likely also in a detached and free-living state.},
}
@article {pmid33024036,
year = {2020},
author = {Hague, MTJ and Caldwell, CN and Cooper, BS},
title = {Pervasive Effects of Wolbachia on Host Temperature Preference.},
journal = {mBio},
volume = {11},
number = {5},
pages = {},
pmid = {33024036},
issn = {2150-7511},
support = {R35 GM124701/GM/NIGMS NIH HHS/United States ; },
abstract = {Heritable symbionts can modify a range of ecologically important host traits, including behavior. About half of all insect species are infected with maternally transmitted Wolbachia, a bacterial endosymbiont known to alter host reproduction, nutrient acquisition, and virus susceptibility. Here, we broadly test the hypothesis that Wolbachia modifies host behavior by assessing the effects of eight different Wolbachia strains on the temperature preference of six Drosophila melanogaster subgroup species. Four of the seven host genotypes infected with A-group Wolbachia strains (wRi in Drosophila simulans, wHa in D. simulans, wSh in Drosophila sechellia, and wTei in Drosophila teissieri) prefer significantly cooler temperatures relative to uninfected genotypes. Contrastingly, when infected with divergent B-group wMau, Drosophila mauritiana prefers a warmer temperature. For most strains, changes to host temperature preference do not alter Wolbachia titer. However, males infected with wSh and wTei tend to experience an increase in titer when shifted to a cooler temperature for 24 h, suggesting that Wolbachia-induced changes to host behavior may promote bacterial replication. Our results indicate that Wolbachia modifications to host temperature preference are likely widespread, which has important implications for insect thermoregulation and physiology. Understanding the fitness consequences of these Wolbachia effects is crucial for predicting evolutionary outcomes of host-symbiont interactions, including how Wolbachia spreads to become common.IMPORTANCE Microbes infect a diversity of species, influencing the performance and fitness of their hosts. Maternally transmitted Wolbachia bacteria infect most insects and other arthropods, making these bacteria some of the most common endosymbionts in nature. Despite their global prevalence, it remains mostly unknown how Wolbachia influence host physiology and behavior to proliferate. We demonstrate pervasive effects of Wolbachia on Drosophila temperature preference. Most hosts infected with A-group Wolbachia prefer cooler temperatures, whereas the one host species infected with divergent B-group Wolbachia prefers warmer temperatures, relative to uninfected genotypes. Changes to host temperature preference generally do not alter Wolbachia abundance in host tissues, but for some A-group strains, adult males have increased Wolbachia titer when shifted to a cooler temperature. This suggests that Wolbachia-induced changes to host behavior may promote bacterial replication. Our results help elucidate the impact of endosymbionts on their hosts amid the global Wolbachia pandemic.},
}
@article {pmid33022256,
year = {2020},
author = {Sogin, EM and Leisch, N and Dubilier, N},
title = {Chemosynthetic symbioses.},
journal = {Current biology : CB},
volume = {30},
number = {19},
pages = {R1137-R1142},
doi = {10.1016/j.cub.2020.07.050},
pmid = {33022256},
issn = {1879-0445},
abstract = {Symbioses between chemosynthetic bacteria and eukaryotic hosts can be found almost everywhere in the ocean, from shallow-water seagrass beds and coral reef sediments to the deep sea. Yet no one knew these existed until 45 years ago, when teeming communities of animals were found thriving at hydrothermal vents two and a half kilometers below the sea surface. The discovery of these lightless ecosystems revolutionized our understanding of the energy sources that fuel life on Earth. Animals thrive at vents because they live in a nutritional symbiosis with chemosynthetic bacteria that grow on chemical compounds gushing out of the vents, such as sulfide and methane, which animals cannot use on their own. The symbionts gain energy from the oxidation of these reduced substrates to fix CO2 and other simple carbon compounds into biomass, which is then transferred to the host. By associating with chemosynthetic bacteria, animals and protists can thrive in environments in which there is not enough organic carbon to support their nutrition, including oligotrophic habitats like coral reefs and seagrass meadows. Chemosymbioses have evolved repeatedly and independently in multiple lineages of marine invertebrates and bacteria, highlighting the strong selective advantage for both hosts and symbionts in forming these associations. Here, we provide a brief overview of chemosynthesis and how these symbioses function. We highlight some of the current research in this field and outline several promising avenues for future research.},
}
@article {pmid33022020,
year = {2020},
author = {Coates, LC and Mahoney, J and Ramsey, JS and Warwick, E and Johnson, R and MacCoss, MJ and Krasnoff, SB and Howe, KJ and Moulton, K and Saha, S and Mueller, LA and Hall, DG and Shatters, RG and Heck, ML and Slupsky, CM},
title = {Development on Citrus medica infected with 'Candidatus Liberibacter asiaticus' has sex-specific and -nonspecific impacts on adult Diaphorina citri and its endosymbionts.},
journal = {PloS one},
volume = {15},
number = {10},
pages = {e0239771},
pmid = {33022020},
issn = {1932-6203},
mesh = {Animals ; Citrus/metabolism/*microbiology/physiology ; Female ; Hemiptera/metabolism/*microbiology/physiology ; Insect Vectors/metabolism/*microbiology/physiology ; Male ; Metabolome/physiology ; Microbiota/physiology ; Oxidative Stress/physiology ; Plant Diseases/*microbiology ; Proteome/metabolism ; Rhizobiaceae/*pathogenicity/*physiology ; Symbiosis/*physiology ; Transcriptome/physiology ; },
abstract = {Huanglongbing (HLB) is a deadly, incurable citrus disease putatively caused by the unculturable bacterium, 'Candidatus Liberibacter asiaticus' (CLas), and transmitted by Diaphorina citri. Prior studies suggest D. citri transmits CLas in a circulative and propagative manner; however, the precise interactions necessary for CLas transmission remain unknown, and the impact of insect sex on D. citri-CLas interactions is poorly understood despite reports of sex-dependent susceptibilities to CLas. We analyzed the transcriptome, proteome, metabolome, and microbiome of male and female adult D. citri reared on healthy or CLas-infected Citrus medica to determine shared and sex-specific responses of D. citri and its endosymbionts to CLas exposure. More sex-specific than shared D. citri responses to CLas were observed, despite there being no difference between males and females in CLas density or relative abundance. CLas exposure altered the abundance of proteins involved in immunity and cellular and oxidative stress in a sex-dependent manner. CLas exposure impacted cuticular proteins and enzymes involved in chitin degradation, as well as energy metabolism and abundance of the endosymbiont 'Candidatus Profftella armatura' in both sexes similarly. Notably, diaphorin, a toxic Profftella-derived metabolite, was more abundant in both sexes with CLas exposure. The responses reported here resulted from a combination of CLas colonization of D. citri as well as the effect of CLas infection on C. medica. Elucidating these impacts on D. citri and their endosymbionts contributes to our understanding of the HLB pathosystem and identifies the responses potentially critical to limiting or promoting CLas acquisition and propagation in both sexes.},
}
@article {pmid33021882,
year = {2020},
author = {Perry, BJ and Ferguson, S and Laugraud, A and Wakelin, SA and Reeve, W and Ronson, CW},
title = {Complete Genome Sequences of Trifolium spp. Inoculant Strains Rhizobium leguminosarum sv. trifolii TA1 and CC275e: Resources for Genomic Study of the Rhizobium-Trifolium Symbiosis.},
journal = {Molecular plant-microbe interactions : MPMI},
volume = {},
number = {},
pages = {MPMI08200220A},
doi = {10.1094/MPMI-08-20-0220-A},
pmid = {33021882},
issn = {0894-0282},
abstract = {Rhizobium leguminosarum symbiovar trifolii strains TA1 and CC275e are nitrogen-fixing microsymbionts of Trifolium spp. and have been used as commercial inoculant strains for clovers in pastoral agriculture in Australia and New Zealand. Here we present the complete genome sequences of both strains, resolving their multipartite genome structures and allowing for future studies using genomic approaches.[Formula: see text] Copyright © 2020 The Author(s). This is an open access article distributed under the CC BY 4.0 International license.},
}
@article {pmid33021711,
year = {2020},
author = {Shan, H and Liu, Y and Luan, J and Liu, S},
title = {New insights into the transovarial transmission of the symbiont Rickettsia in whiteflies.},
journal = {Science China. Life sciences},
volume = {},
number = {},
pages = {},
doi = {10.1007/s11427-020-1801-7},
pmid = {33021711},
issn = {1869-1889},
abstract = {Endosymbiont transmission via eggs to future host generations has been recognized as the main strategy for its persistence in insect hosts; however, the mechanisms for transmission have yet to be elucidated. Here, we describe the dynamic locations of Rickettsia in the ovarioles and eggs during oogenesis and embryogenesis in a globally significant pest whitefly Bemisia tabaci. Field populations of the whitefly have a high prevalence of Rickettsia, and in all Rickettsia-infected individuals, the bacterium distributes in the body cavity of the host, especially in the midgut, fat body, hemocytes, hemolymph, and near bacteriocytes. The distribution of Rickettsia was subjected to dynamic changes in the ovary during oogenesis, and our ultrastructural observations indicated that the bacteria infect host ovarioles during early developmental stages via two routes: (i) invasion of the tropharium by endocytosis and then transmission into vitellarium via nutritive cord and (ii) entry into vitellarium by hijacking bacteriocyte translocation. Most of the Rickettsia are degraded in the oocyte cytoplasm in late-stage oogenesis. However, a few reside beneath the vitelline envelope of mature eggs, spread into the embryo, and proliferate during embryogenesis to sustain high-fidelity transmission to the next generation. Our findings provide novel insights into the maternal transmission underpinning the persistence and spread of insect symbionts.},
}
@article {pmid33020322,
year = {2020},
author = {Müller, LM},
title = {An Evolutionary Perspective on LysM Receptors Reveals Conserved Mechanisms for Microbial Signal Perception.},
journal = {Plant physiology},
volume = {184},
number = {2},
pages = {562-563},
pmid = {33020322},
issn = {1532-2548},
mesh = {*Nitrogen ; Prednisolone ; *Symbiosis ; },
}
@article {pmid33020252,
year = {2020},
author = {Sun, G and Putkaradze, N and Bohnacker, S and Jonczyk, R and Fida, T and Hoffmann, T and Bernhardt, R and Härtl, K and Schwab, W},
title = {Six Uridine-Diphosphate Glycosyltransferases Catalyze the Glycosylation of Bioactive C13-Apocarotenols.},
journal = {Plant physiology},
volume = {184},
number = {4},
pages = {1744-1761},
pmid = {33020252},
issn = {1532-2548},
abstract = {C13-apocarotenoids (norisoprenoids) are carotenoid-derived oxidation products that perform important physiological functions in plants. Although their biosynthetic pathways have been extensively studied, their metabolism including glycosylation remains poorly understood. Candidate uridine-diphosphate glycosyltransferase genes (UGTs) were selected based on their high transcript abundance in comparison with other UGTs in vegetative tissues of Nicotiana benthamiana and peppermint (Mentha × piperita), as these tissues are rich sources of apocarotenoid glucosides. Hydroxylated C13-apocarotenol substrates were produced by P450-catalyzed biotransformation and microbial/plant enzyme systems were established for the synthesis of glycosides. Natural substrates were identified by physiological aglycone libraries prepared from isolated plant glycosides. In total, we identified six UGTs that catalyze the glucosylation of C13-apocarotenols, where Glc is bound either to the cyclohexene ring or the butane side chain. MpUGT86C10 is a superior novel enzyme that catalyzes the glucosylation of allelopathic 3-hydroxy-α-damascone, 3-oxo-α-ionol, 3-oxo-7,8-dihydro-α-ionol (Blumenol C), and 3-hydroxy-7,8-dihydro-β-ionol, whereas a germination test demonstrated the higher phytotoxic potential of a norisoprenoid glucoside in comparison to its aglycone. Glycosylation of C13-apocarotenoids has several functions in plants, including increased allelopathic activity of the aglycone, facilitating exudation by roots and allowing symbiosis with arbuscular mycorrhizal fungi. The results enable in-depth analysis of the roles of glycosylated norisoprenoid allelochemicals, the physiological functions of apocarotenoids during arbuscular mycorrhizal colonization, and the associated maintenance of carotenoid homeostasis.},
}
@article {pmid33016489,
year = {2020},
author = {Geretharan, T and Jeyakumar, P and Bretherton, M and Anderson, CWN},
title = {Fluorine and white clover: Assessing fluorine's impact on Rhizobium leguminosarum.},
journal = {Journal of environmental quality},
volume = {49},
number = {4},
pages = {987-999},
doi = {10.1002/jeq2.20089},
pmid = {33016489},
issn = {1537-2537},
support = {//Fertiliser Association of New Zealand/ ; },
mesh = {Fluorine ; New Zealand ; *Rhizobium leguminosarum ; Symbiosis ; *Trifolium ; },
abstract = {The soil fluorine (F) concentration in New Zealand agricultural soils has increased with time as a direct result of the widespread application of phosphate fertilizer to land. Elevated soil F concentrations may potentially harm soil microorganisms, which are important for nutrient cycling and soil formation. Rhizobium leguminosarum is a N2 -fixing soil bacterium that is a fundamental component in New Zealand legume-based pastoral farming. Any impact of F on Rhizobium leguminosarum would have an adverse effect on New Zealand pasture production. In this study, F toxicity to Rhizobium leguminosarum was examined as a first step to develop F guideline values for New Zealand agricultural soils. Bottle-based experiments were conducted to examine the effect of the F- ion on Rhizobium-white clover (Trifolium repens L.) symbiosis by observing nodule morphology and growth. Results indicate that the F- concentration that causes 10% inhibition of Rhizobium respiration (IC10) for F- toxicity to Rhizobium leguminosarum was >100 mg F- L-1 . Significant morphological changes occurred when Rhizobium was exposed to F concentrations of 500 and 1000 mg L-1 . Both light and transmission electron micrographs confirmed that the Rhizobium leguminosarum-white clover interaction was not influenced by F- concentrations >100 mg L-1 . The toxic F- concentration for Rhizobium leguminosarum determined in this study is orders of magnitude higher than the F- concentration in New Zealand agriculture soils under "normal conditions." There appears to be no indication of imminent risk of soil F to Rhizobium leguminosarum.},
}
@article {pmid33016310,
year = {2020},
author = {Bamba, M and Aoki, S and Kajita, T and Setoguchi, H and Watano, Y and Sato, S and Tsuchimatsu, T},
title = {Massive rhizobial genomic variation associated with partner quality in Lotus-Mesorhizobium symbiosis.},
journal = {FEMS microbiology ecology},
volume = {96},
number = {12},
pages = {},
doi = {10.1093/femsec/fiaa202},
pmid = {33016310},
issn = {1574-6941},
abstract = {Variation in partner quality is commonly observed in diverse cooperative relationships, despite the theoretical prediction that selection favoring high-quality partners should eliminate such variation. Here, we investigated how genetic variation in partner quality could be maintained in the nitrogen-fixing mutualism between Lotus japonicus and Mesorhizobium bacteria. We reconstructed de novo assembled full-genome sequences from nine rhizobial symbionts, finding massive variation in the core genome and the similar symbiotic islands, indicating recent horizontal gene transfer (HGT) of the symbiosis islands into diverse Mesorhizobium lineages. A cross-inoculation experiment using 9 sequenced rhizobial symbionts and 15 L. japonicus accessions revealed extensive quality variation represented by plant growth phenotypes, including genotype-by-genotype interactions. Variation in quality was not associated with the presence/absence variation in known symbiosis-related genes in the symbiosis island; rather, it showed significant correlation with the core genome variation. Given the recurrent HGT of the symbiosis islands into diverse Mesorhizobium strains, local Mesorhizobium communities could serve as a major source of variation for core genomes, which might prevent variation in partner quality from fixing, even in the presence of selection favoring high-quality partners. These findings highlight the novel role of HGT of symbiosis islands in maintaining partner quality variation in the legume-rhizobia symbiosis.},
}
@article {pmid33014021,
year = {2020},
author = {Liu, J and Yu, X and Qin, Q and Dinkins, RD and Zhu, H},
title = {The Impacts of Domestication and Breeding on Nitrogen Fixation Symbiosis in Legumes.},
journal = {Frontiers in genetics},
volume = {11},
number = {},
pages = {00973},
pmid = {33014021},
issn = {1664-8021},
abstract = {Legumes are the second most important family of crop plants. One defining feature of legumes is their unique ability to establish a nitrogen-fixing root nodule symbiosis with soil bacteria known as rhizobia. Since domestication from their wild relatives, crop legumes have been under intensive breeding to improve yield and other agronomic traits but with little attention paid to the belowground symbiosis traits. Theoretical models predict that domestication and breeding processes, coupled with high-input agricultural practices, might have reduced the capacity of crop legumes to achieve their full potential of nitrogen fixation symbiosis. Testing this prediction requires characterizing symbiosis traits in wild and breeding populations under both natural and cultivated environments using genetic, genomic, and ecological approaches. However, very few experimental studies have been dedicated to this area of research. Here, we review how legumes regulate their interactions with soil rhizobia and how domestication, breeding and agricultural practices might have affected nodulation capacity, nitrogen fixation efficiency, and the composition and function of rhizobial community. We also provide a perspective on how to improve legume-rhizobial symbiosis in sustainable agricultural systems.},
}
@article {pmid33013954,
year = {2020},
author = {Berger, A and Boscari, A and Horta Araújo, N and Maucourt, M and Hanchi, M and Bernillon, S and Rolin, D and Puppo, A and Brouquisse, R},
title = {Plant Nitrate Reductases Regulate Nitric Oxide Production and Nitrogen-Fixing Metabolism During the Medicago truncatula-Sinorhizobium meliloti Symbiosis.},
journal = {Frontiers in plant science},
volume = {11},
number = {},
pages = {1313},
pmid = {33013954},
issn = {1664-462X},
abstract = {Nitrate reductase (NR) is the first enzyme of the nitrogen reduction pathway in plants, leading to the production of ammonia. However, in the nitrogen-fixing symbiosis between legumes and rhizobia, atmospheric nitrogen (N2) is directly reduced to ammonia by the bacterial nitrogenase, which questions the role of NR in symbiosis. Next to that, NR is the best-characterized source of nitric oxide (NO) in plants, and NO is known to be produced during the symbiosis. In the present study, we first surveyed the three NR genes (MtNR1, MtNR2, and MtNR3) present in the Medicago truncatula genome and addressed their expression, activity, and potential involvement in NO production during the symbiosis between M. truncatula and Sinorhizobium meliloti. Our results show that MtNR1 and MtNR2 gene expression and activity are correlated with NO production throughout the symbiotic process and that MtNR1 is particularly involved in NO production in mature nodules. Moreover, NRs are involved together with the mitochondrial electron transfer chain in NO production throughout the symbiotic process and energy regeneration in N2-fixing nodules. Using an in vivo NMR spectrometric approach, we show that, in mature nodules, NRs participate also in the regulation of energy state, cytosolic pH, carbon and nitrogen metabolism under both normoxia and hypoxia. These data point to the importance of NR activity for the N2-fixing symbiosis and provide a first explanation of its role in this process.},
}
@article {pmid33013799,
year = {2020},
author = {Chakraborty, A and Modlinger, R and Ashraf, MZ and Synek, J and Schlyter, F and Roy, A},
title = {Core Mycobiome and Their Ecological Relevance in the Gut of Five Ips Bark Beetles (Coleoptera: Curculionidae: Scolytinae).},
journal = {Frontiers in microbiology},
volume = {11},
number = {},
pages = {568853},
pmid = {33013799},
issn = {1664-302X},
abstract = {Bark beetles are destructive forest pests considering their remarkable contribution to forest depletion. Their association with fungi is useful against the challenges of survival on the noxious and nutritionally limited substrate, i.e., conifer tissues. Fungal symbionts help the beetles in nutrient acquisition and detoxification of toxic tree secondary metabolites. Although gut is the prime location for food digestion and detoxification, limited information is available on gut-mycobiome of bark beetles. The present study screened the gut-mycobiont from six bark beetles (five Ips and one non-Ips) from Scolytinae subfamily using high-throughput sequencing and explored their putative role in symbiosis with the host insect. Results revealed the predominance of four fungal classes- Sordariomycetes, Saccharomycetes, Eurothiomycetes, and Dothidomycetes in all bark beetles. Apart from these, Agaricomycetes, Leothiomycetes, Incertae sedis Basidiomycota, Tremellomycetes, Lecanoromycetes, and Microbotryomycetes were also documented in different beetles. Five Ips bark beetles share a consortium of core fungal communities in their gut tissues consisting of 47 operational taxonomic units (OTUs) belonging to 19 fungal genera. The majority of these core fungal genera belong to the phylum Ascomycota. LEfSe analysis revealed a set of species-specific fungal biomarkers in bark beetles. The present study identified the gut mycobiont assemblage in bark beetles and their putative ecological relevance. An enriched understanding of bark beetle-fungal symbiosis is not only filling the existing knowledge gap in the field but may also unleash an unforeseen potential for future bark beetle management.},
}
@article {pmid33012965,
year = {2020},
author = {Yang, J and Zheng, K},
title = {The effect of adaptive behavior on risk propagation in industrial symbiosis networks.},
journal = {Physics letters. A},
volume = {384},
number = {36},
pages = {126915},
pmid = {33012965},
issn = {0375-9601},
abstract = {The complex symbiotic relationship in the industrial symbiosis network (ISN) may cause new risks for firms. In view of this problem, previous studies mainly regard the ISN as a static system, without considering the adaptive behavior of firms. This paper establishes a risk propagation model of the ISN based on the change of firm state, proposes four kinds of reconnection strategies to model the adaptive behavior, and uses numerical simulation to investigate the effect of adaptive behavior on risk propagation. The results demonstrate that all the reconnection strategies play an inhibitory role in the risk propagation. Therein, the effectiveness of PP strategy is the best, followed by RR strategy, and DP (SP) strategy. In any case, the effect of reconnection strategies on risk propagation will improve with the increase of the disconnection probability and network resilience. Additionally, the more decentralized weight distribution will weaken the inhibition of adaptive behavior on risk propagation.},
}
@article {pmid33012868,
year = {2020},
author = {Rishi, P and Thakur, K and Vij, S and Rishi, L and Singh, A and Kaur, IP and Patel, SKS and Lee, JK and Kalia, VC},
title = {Diet, Gut Microbiota and COVID-19.},
journal = {Indian journal of microbiology},
volume = {},
number = {},
pages = {1-10},
pmid = {33012868},
issn = {0046-8991},
abstract = {Worldwide, millions of individuals have been affected by the prevailing SARS-CoV-2. Therefore, a robust immune system remains indispensable, as an immunocompromised host status has proven to be fatal. In the absence of any specific antiviral drug/vaccine, COVID-19 related drug repurposing along with various other non-pharmacological measures coupled with lockdown have been employed to combat this infection. In this context, a plant based rich fiber diet, which happens to be consumed by a majority of the Indian population, appears to be advantageous, as it replenishes the host gut microbiota with beneficial microbes thereby leading to a symbiotic association conferring various health benefits to the host including enhanced immunity. Further, implementation of the lockdown which has proven to be a good non-pharmacological measure, seems to have resulted in consumption of home cooked healthy diet, thereby enriching the beneficial microflora in the gut, which might have resulted in better prognosis of COVID-19 patients in India in comparison to that observed in the western countries.},
}
@article {pmid33011965,
year = {2020},
author = {Riccio, P and Rossano, R},
title = {The human gut microbiota is neither an organ nor a commensal.},
journal = {FEBS letters},
volume = {594},
number = {20},
pages = {3262-3271},
doi = {10.1002/1873-3468.13946},
pmid = {33011965},
issn = {1873-3468},
abstract = {The recent explosive increase in the number of works on gut microbiota has been accompanied by the spread of rather vague or improper definitions, chosen more for common use than for experimental evidence. Among them are those defining the human gut microbiota as an organ of our body or as a commensal. But, is the human gut microbiota an organ or a commensal? Here, we address this issue to spearhead a reflection on the real roles of the human gut microbiota in our life. Actually, the misuse of the vocabulary used to describe the properties and functions of the gut microbiota may generate confusion and cause misunderstandings both in the scientific community and among the general public.},
}
@article {pmid33011742,
year = {2020},
author = {Taylor, JA and Palladino, G and Wemheuer, B and Steinert, G and Sipkema, D and Williams, TJ and Thomas, T},
title = {Phylogeny resolved, metabolism revealed: functional radiation within a widespread and divergent clade of sponge symbionts.},
journal = {The ISME journal},
volume = {},
number = {},
pages = {},
doi = {10.1038/s41396-020-00791-z},
pmid = {33011742},
issn = {1751-7370},
abstract = {The symbiosis between bacteria and sponges has arguably the longest evolutionary history for any extant metazoan lineage, yet little is known about bacterial evolution or adaptation in this process. An example of often dominant and widespread bacterial symbionts of sponges is a clade of uncultured and uncharacterised Proteobacteria. Here we set out to characterise this group using metagenomics, in-depth phylogenetic analyses, metatranscriptomics, and fluorescence in situ hybridisation microscopy. We obtained five metagenome-assembled-genomes (MAGs) from different sponge species that, together with a previously published MAG (AqS2), comprise two families within a new gammaproteobacterial order that we named UTethybacterales. Members of this order share a heterotrophic lifestyle but vary in their predicted ability to use various carbon, nitrogen and sulfur sources, including taurine, spermidine and dimethylsulfoniopropionate. The deep branching of the UTethybacterales within the Gammaproteobacteria and their almost exclusive presence in sponges suggests they have entered a symbiosis with their host relatively early in evolutionary time and have subsequently functionally radiated. This is reflected in quite distinct lifestyles of various species of UTethybacterales, most notably their diverse morphologies, predicted substrate preferences, and localisation within the sponge tissue. This study provides new insight into the evolution of metazoan-bacteria symbiosis.},
}
@article {pmid33011226,
year = {2021},
author = {Chan, JWJ and Boo, MV and Wong, WP and Chew, SF and Ip, YK},
title = {Illumination enhances the protein abundance of sarcoplasmic reticulum Ca2+-ATPases-like transporter in the ctenidium and whitish inner mantle of the giant clam, Tridacna squamosa, to augment exogenous Ca2+ uptake and shell formation, respectively.},
journal = {Comparative biochemistry and physiology. Part A, Molecular & integrative physiology},
volume = {251},
number = {},
pages = {110811},
doi = {10.1016/j.cbpa.2020.110811},
pmid = {33011226},
issn = {1531-4332},
abstract = {The fluted giant clam, Tridacna squamosa, can perform light-enhanced shell formation, aided by its symbiotic dinoflagellates (Symbiodinium, Cladocopium, Durusdinium), which are able to donate organic nutrients to the host. During light-enhanced shell formation, increased Ca2+ transport from the hemolymph through the shell-facing epithelium of the inner mantle to the extrapallial fluid, where calcification occurs, is necessary. Additionally, there must be increased absorption of exogenous Ca2+ from the surrounding seawater, across the epithelial cells of the ctenidium (gill) into the hemolymph, to supply sufficient Ca2+ for light-enhanced shell formation. When Ca2+ moves across these epithelial cells, the low intracellular Ca2+ concentration must be maintained. Sarco(endo)plasmic reticulum Ca2+-ATPase (SERCA) regulates the intracellular Ca2+ concentration by pumping Ca2+ into the sarcoplasmic/endoplasmic reticulum (SR/ER) and Golgi apparatus. Indeed, the ctenidium and inner mantle of T. squamosa, expressed a homolog of SERCA (SERCA-like transporter) that consists of 3009 bp, encoding 1002 amino acids of 110.6 kDa. SERCA-like-immunolabeling was non-uniform in the cytoplasm of epithelial cells of ctenidial filaments, and that of the shell-facing epithelial cells of the inner mantle. Importantly, the protein abundance of SERCA-like increased significantly in the ctenidium and the inner mantle of T. squamosa after 12 h and 6 h, respectively, of light exposure. This would increase the capacity of pumping Ca2+ into the endoplasmic reticulum and avert a possible surge in the cytosolic Ca2+ concentration in epithelial cells of the ctenidial filaments during light-enhanced Ca2+ absorption, and in cells of the shell-facing epithelium of the inner mantle during light-enhanced shell formation.},
}
@article {pmid33008816,
year = {2020},
author = {Hammer, TJ and Dickerson, JC and McMillan, WO and Fierer, N},
title = {Heliconius Butterflies Host Characteristic and Phylogenetically Structured Adult-Stage Microbiomes.},
journal = {Applied and environmental microbiology},
volume = {86},
number = {24},
pages = {},
pmid = {33008816},
issn = {1098-5336},
mesh = {Animals ; Bacteria/*isolation & purification ; *Bacterial Physiological Phenomena ; Butterflies/*microbiology ; Host Microbial Interactions ; *Microbiota ; Phylogeny ; Sequence Analysis, RNA/*methods ; Species Specificity ; },
abstract = {Lepidoptera (butterflies and moths) are diverse and ecologically important, yet we know little about how they interact with microbes as adults. Due to metamorphosis, the form and function of their adult-stage microbiomes might be very different from those of microbiomes in the larval stage (caterpillars). We studied adult-stage microbiomes of Heliconius and closely related passion-vine butterflies (Heliconiini), which are an important model system in evolutionary biology. To characterize the structure and dynamics of heliconiine microbiomes, we used field collections of wild butterflies, 16S rRNA gene sequencing, quantitative PCR, and shotgun metagenomics. We found that Heliconius butterflies harbor simple and abundant bacterial communities that are moderately consistent among conspecific individuals and over time. Heliconiine microbiomes also exhibited a strong signal of the host phylogeny, with a major distinction between Heliconius and other butterflies. These patterns were largely driven by differing relative abundances of bacterial phylotypes shared among host species and genera, as opposed to the presence or absence of host-specific phylotypes. We suggest that the phylogenetic structure in heliconiine microbiomes arises from conserved host traits that differentially filter microbes from the environment. While the relative importance of different traits remains unclear, our data indicate that pollen feeding (unique to Heliconius) is not a primary driver. Using shotgun metagenomics, we also discovered trypanosomatids and microsporidia to be prevalent in butterfly guts, raising the possibility of antagonistic interactions between eukaryotic parasites and colocalized gut bacteria. Our discovery of characteristic and phylogenetically structured microbiomes provides a foundation for tests of adult-stage microbiome function, a poorly understood aspect of lepidopteran biology.IMPORTANCE Many insects host microbiomes with important ecological functions. However, the prevalence of this phenomenon is unclear because in many insect taxa, microbiomes have been studied in only part of the life cycle, if at all. A prominent example is butterflies and moths, in which the composition and functional role of adult-stage microbiomes are largely unknown. We comprehensively characterized microbiomes in adult passion-vine butterflies. Butterfly-associated bacterial communities are generally abundant in guts, consistent within populations, and composed of taxa widely shared among hosts. More closely related butterflies harbor more similar microbiomes, with the most dramatic shift in microbiome composition occurring in tandem with a suite of ecological and life history traits unique to the genus Heliconius Butterflies are also frequently infected with previously undescribed eukaryotic parasites, which may interact with bacteria in important ways. These findings advance our understanding of butterfly biology and insect-microbe interactions generally.},
}
@article {pmid33008049,
year = {2020},
author = {Kosolapova, AO and Antonets, KS and Belousov, MV and Nizhnikov, AA},
title = {Biological Functions of Prokaryotic Amyloids in Interspecies Interactions: Facts and Assumptions.},
journal = {International journal of molecular sciences},
volume = {21},
number = {19},
pages = {},
pmid = {33008049},
issn = {1422-0067},
support = {17-16-01100//Russian Science Foundation/ ; 19-76-00026//Russian Science Foundation/ ; },
abstract = {Amyloids are fibrillar protein aggregates with an ordered spatial structure called "cross-β". While some amyloids are associated with development of approximately 50 incurable diseases of humans and animals, the others perform various crucial physiological functions. The greatest diversity of amyloids functions is identified within prokaryotic species where they, being the components of the biofilm matrix, function as adhesins, regulate the activity of toxins and virulence factors, and compose extracellular protein layers. Amyloid state is widely used by different pathogenic bacterial species in their interactions with eukaryotic organisms. These amyloids, being functional for bacteria that produce them, are associated with various bacterial infections in humans and animals. Thus, the repertoire of the disease-associated amyloids includes not only dozens of pathological amyloids of mammalian origin but also numerous microbial amyloids. Although the ability of symbiotic microorganisms to produce amyloids has recently been demonstrated, functional roles of prokaryotic amyloids in host-symbiont interactions as well as in the interspecies interactions within the prokaryotic communities remain poorly studied. Here, we summarize the current findings in the field of prokaryotic amyloids, classify different interspecies interactions where these amyloids are involved, and hypothesize about their real occurrence in nature as well as their roles in pathogenesis and symbiosis.},
}
@article {pmid33006991,
year = {2020},
author = {Swain, JK and Carpio, Y and Johansen, LH and Velazquez, J and Hernandez, L and Leal, Y and Kumar, A and Estrada, MP},
title = {Impact of a candidate vaccine on the dynamics of salmon lice (Lepeophtheirus salmonis) infestation and immune response in Atlantic salmon (Salmo salar L.).},
journal = {PloS one},
volume = {15},
number = {10},
pages = {e0239827},
pmid = {33006991},
issn = {1932-6203},
mesh = {Animals ; Copepoda/*immunology ; Fish Diseases/parasitology/*prevention & control ; Host-Parasite Interactions ; Ribosomal Proteins/*immunology ; Salmo salar/*immunology ; Vaccination/veterinary ; Vaccines/*therapeutic use ; },
abstract = {Infection with parasitic copepod salmon louse Lepeophtheirus salmonis, represents one of the most important limitations to sustainable Atlantic salmon (Salmo salar L.) farming today in the North Atlantic region. The parasite exerts negative impact on health, growth and welfare of farmed fish as well as impact on wild salmonid populations. It is therefore central to ensure continuous low level of salmon lice with the least possible handling of the salmon and drug use. To address this, vaccination is a cost-effective and environmentally friendly control approach. In this study, efficacy of a vaccine candidate, containing a peptide derived from ribosomal protein P0, was validated post infestation with L. salmonis, at the lab-scale. The sampling results showed good potential of the vaccine candidate when administered intraperitoneally in the host, in reducing the ectoparasite load, through reduction of adult female lice counts and fecundity and with greater presumptive effect in F1 lice generation. The sampling results correlated well with the differential modulation of pro-inflammatory, Th1, Th2 and T regulatory mediators at the transcript level at different lice stages. Overall, the results supports approximately 56% efficacy when administered by intraperitoneal injection. However, additional validation is necessary under large-scale laboratory trial for further application under field conditions.},
}
@article {pmid33005311,
year = {2020},
author = {Jung, J and Kim, JS and Taffner, J and Berg, G and Ryu, CM},
title = {Archaea, tiny helpers of land plants.},
journal = {Computational and structural biotechnology journal},
volume = {18},
number = {},
pages = {2494-2500},
pmid = {33005311},
issn = {2001-0370},
abstract = {Archaea are members of most microbiomes. While archaea are highly abundant in extreme environments, they are less abundant and diverse in association with eukaryotic hosts. Nevertheless, archaea are a substantial constituent of plant-associated ecosystems in the aboveground and belowground phytobiome. Only a few studies have investigated the role of archaea in plant health and its potential symbiosis in ecosystems. This review discusses recent progress in identifying how archaea contribute to plant traits such as growth, adaptation to abiotic stresses, and immune activation. We synthesized the most recent functional and molecular data on archaea, including root colonization and the volatile emission to activate plant systemic immunity. These data represent a paradigm shift in our understanding of plant-microbiota interactions.},
}
@article {pmid33002237,
year = {2020},
author = {Davies, SW and Moreland, KN and Wham, DC and Kanke, MR and Matz, MV},
title = {Cladocopium community divergence in two Acropora coral hosts across multiple spatial scales.},
journal = {Molecular ecology},
volume = {29},
number = {23},
pages = {4559-4572},
doi = {10.1111/mec.15668},
pmid = {33002237},
issn = {1365-294X},
support = {IOS-1258058//National Science Foundation/ ; OCE-0928764//National Science Foundation/ ; NA05OAR4301108//National Oceanic and Atmospheric Administration/ ; },
abstract = {Many broadly-dispersing corals acquire their algal symbionts (Symbiodiniaceae) "horizontally" from their environment upon recruitment. Horizontal transmission could promote coral fitness across diverse environments provided that corals can associate with divergent algae across their range and that these symbionts exhibit reduced dispersal potential. Here we quantified community divergence of Cladocopium algal symbionts in two coral host species (Acropora hyacinthus, Acropora digitifera) across two spatial scales (reefs on the same island, and between islands) across the Micronesian archipelago using microsatellites. We find that both hosts associated with a variety of multilocus genotypes (MLG) within two genetically distinct Cladocopium lineages (C40, C21), confirming that Acropora coral hosts associate with a range of Cladocopium symbionts across this region. Both C40 and C21 included multiple asexual lineages bearing identical MLGs, many of which spanned host species, reef sites within islands, and even different islands. Both C40 and C21 exhibited moderate host specialization and divergence across islands. In addition, within every island, algal symbiont communities were significantly clustered by both host species and reef site, highlighting that coral-associated Cladocopium communities are structured across small spatial scales and within hosts on the same reef. This is in stark contrast to their coral hosts, which never exhibited significant genetic divergence between reefs on the same island. These results support the view that horizontal transmission could improve local fitness for broadly dispersing Acropora coral species.},
}
@article {pmid33002000,
year = {2020},
author = {Sorroche, F and Morales, V and Mouffok, S and Pichereaux, C and Garnerone, AM and Zou, L and Soni, B and Carpéné, MA and Gargaros, A and Maillet, F and Burlet-Schiltz, O and Poinsot, V and Polard, P and Gough, C and Batut, J},
title = {The ex planta signal activity of a Medicago ribosomal uL2 protein suggests a moonlighting role in controlling secondary rhizobial infection.},
journal = {PloS one},
volume = {15},
number = {10},
pages = {e0235446},
pmid = {33002000},
issn = {1932-6203},
mesh = {Coinfection/prevention & control ; Ethylenes/metabolism ; Gene Expression Regulation, Plant ; Genes, Plant ; *Medicago truncatula/genetics/metabolism/microbiology ; Plant Immunity/genetics ; Plant Proteins/genetics/*metabolism ; Plant Root Nodulation/physiology ; Plant Roots/metabolism/microbiology ; Ribosomal Proteins/genetics/*metabolism ; Root Nodules, Plant/*metabolism/microbiology ; Signal Transduction ; Sinorhizobium meliloti/*metabolism ; Symbiosis ; },
abstract = {We recently described a regulatory loop, which we termed autoregulation of infection (AOI), by which Sinorhizobium meliloti, a Medicago endosymbiont, downregulates the root susceptibility to secondary infection events via ethylene. AOI is initially triggered by so-far unidentified Medicago nodule signals named signal 1 and signal 1' whose transduction in bacteroids requires the S. meliloti outer-membrane-associated NsrA receptor protein and the cognate inner-membrane-associated adenylate cyclases, CyaK and CyaD1/D2, respectively. Here, we report on advances in signal 1 identification. Signal 1 activity is widespread as we robustly detected it in Medicago nodule extracts as well as in yeast and bacteria cell extracts. Biochemical analyses indicated a peptidic nature for signal 1 and, together with proteomic analyses, a universally conserved Medicago ribosomal protein of the uL2 family was identified as a candidate signal 1. Specifically, MtRPuL2A (MtrunA17Chr7g0247311) displays a strong signal activity that requires S. meliloti NsrA and CyaK, as endogenous signal 1. We have shown that MtRPuL2A is active in signaling only in a non-ribosomal form. A Medicago truncatula mutant in the major symbiotic transcriptional regulator MtNF-YA1 lacked most signal 1 activity, suggesting that signal 1 is under developmental control. Altogether, our results point to the MtRPuL2A ribosomal protein as the candidate for signal 1. Based on the Mtnf-ya1 mutant, we suggest a link between root infectiveness and nodule development. We discuss our findings in the context of ribosomal protein moonlighting.},
}
@article {pmid32999061,
year = {2020},
author = {Sugiura, Y and Akiyama, R and Tanaka, S and Yano, K and Kameoka, H and Marui, S and Saito, M and Kawaguchi, M and Akiyama, K and Saito, K},
title = {Myristate can be used as a carbon and energy source for the asymbiotic growth of arbuscular mycorrhizal fungi.},
journal = {Proceedings of the National Academy of Sciences of the United States of America},
volume = {117},
number = {41},
pages = {25779-25788},
pmid = {32999061},
issn = {1091-6490},
mesh = {Carbon/metabolism ; Cell Wall/metabolism ; Energy Metabolism ; Glomeromycota/growth & development/*metabolism ; Hyphae/growth & development/metabolism ; Mycorrhizae/growth & development/*metabolism ; Myristates/*metabolism ; },
abstract = {Arbuscular mycorrhizal (AM) fungi, forming symbiotic associations with land plants, are obligate symbionts that cannot complete their natural life cycle without a host. The fatty acid auxotrophy of AM fungi is supported by recent studies showing that lipids synthesized by the host plants are transferred to the fungi, and that the latter lack genes encoding cytosolic fatty acid synthases. Therefore, to establish an asymbiotic cultivation system for AM fungi, we tried to identify the fatty acids that could promote biomass production. To determine whether AM fungi can grow on medium supplied with fatty acids or lipids under asymbiotic conditions, we tested eight saturated or unsaturated fatty acids (C12 to C18) and two β-monoacylglycerols. Only myristate (C14:0) led to an increase in the biomass of Rhizophagus irregularis, inducing extensive hyphal growth and formation of infection-competent secondary spores. However, such spores were smaller than those generated symbiotically. Furthermore, we demonstrated that R. irregularis can take up fatty acids in its branched hyphae and use myristate as a carbon and energy source. Myristate also promoted the growth of Rhizophagus clarus and Gigaspora margarita Finally, mixtures of myristate and palmitate accelerated fungal growth and induced a substantial change in fatty acid composition of triacylglycerol compared with single myristate application, although palmitate was not used as a carbon source for cell wall biosynthesis in this culture system. Our findings demonstrate that myristate boosts the asymbiotic growth of AM fungi and can also serve as a carbon and energy source.},
}
@article {pmid32999026,
year = {2020},
author = {Mirzakhanyan, Y and Gershon, PD},
title = {Structure-Based Deep Mining Reveals First-Time Annotations for 46 Percent of the Dark Annotation Space of the 9,671-Member Superproteome of the Nucleocytoplasmic Large DNA Viruses.},
journal = {Journal of virology},
volume = {94},
number = {24},
pages = {},
pmid = {32999026},
issn = {1098-5514},
abstract = {We conducted an exhaustive search for three-dimensional structural homologs to the proteins of 20 key phylogenetically distinct nucleocytoplasmic DNA viruses (NCLDV). Structural matches covered 429 known protein domain superfamilies, with the most highly represented being ankyrin repeat, P-loop NTPase, F-box, protein kinase, and membrane occupation and recognition nexus (MORN) repeat. Domain superfamily diversity correlated with genome size, but a diversity of around 200 superfamilies appeared to correlate with an abrupt switch to paralogization. Extensive structural homology was found across the range of eukaryotic RNA polymerase II subunits and their associated basal transcription factors, with the coordinated gain and loss of clusters of subunits on a virus-by-virus basis. The total number of predicted endonucleases across the 20 NCLDV was nearly quadrupled from 36 to 132, covering much of the structural and functional diversity of endonucleases throughout the biosphere in DNA restriction, repair, and homing. Unexpected findings included capsid protein-transcription factor chimeras; endonuclease chimeras; enzymes for detoxification; antimicrobial peptides and toxin-antitoxin systems associated with symbiosis, immunity, and addiction; and novel proteins for membrane abscission and protein turnover.IMPORTANCE We extended the known annotation space for the NCLDV by 46%, revealing high-probability structural matches for fully 45% of the 9,671 query proteins and confirming up to 98% of existing annotations per virus. The most prevalent protein families included ankyrin repeat- and MORN repeat-containing proteins, many of which included an F-box, suggesting extensive host cell modulation among the NCLDV. Regression suggested a minimum requirement for around 36 protein structural superfamilies for a viable NCLDV, and beyond around 200 superfamilies, genome expansion by the acquisition of new functions was abruptly replaced by paralogization. We found homologs to herpesvirus surface glycoprotein gB in cytoplasmic viruses. This study provided the first prediction of an endonuclease in 10 of the 20 viruses examined; the first report in a virus of a phenolic acid decarboxylase, proteasomal subunit, or cysteine knot (defensin) protein; and the first report of a prokaryotic-type ribosomal protein in a eukaryotic virus.},
}
@article {pmid32995943,
year = {2020},
author = {McGuiness, PN and Reid, JB and Foo, E},
title = {Brassinosteroids play multiple roles in nodulation of pea via interactions with ethylene and auxin.},
journal = {Planta},
volume = {252},
number = {4},
pages = {70},
doi = {10.1007/s00425-020-03478-z},
pmid = {32995943},
issn = {1432-2048},
support = {FT140100770//Australian Research Council/ ; DP140101709//Australian Research Council/ ; },
abstract = {MAIN CONCLUSION: A comprehensive analysis of the role of brassinosteroids in nodulation, including their interactions with auxin and ethylene revealed that brassinosteroids inhibit infection, promote nodule initiation but do not influence nodule organogenesis or function. Nodulation, the symbiosis between legumes and rhizobial bacteria, is regulated by a suite of hormones including brassinosteroids. Previous studies have found that brassinosteroids promote nodule number by inhibiting ethylene biosynthesis. In this study, we examined the influence of brassinosteroids on the various stages of infection and nodule development. We utilise pea mutants, including brassinosteroid mutants lk, lka and lkb, the ethylene insensitive ein2 mutant and the lk ein2 double mutant, along with transgenic lines expressing the DR5::GUS auxin activity marker to investigate how brassinosteroids interact with ethylene and auxin during nodulation. We show that brassinosteroids inhibit the early stages of nodulation, including auxin accumulation, root hair deformation and infection thread formation, and demonstrate that infection thread formation is regulated by brassinosteroids in an ethylene independent manner. In contrast, brassinosteroids appear to act as promoters of nodule initiation through both an ethylene dependent and independent pathway. Although brassinosteroids positively influence the ultimate number of nodules formed, we found that brassinosteroid-deficiency did not influence nodule structure including the vascular pattern of auxin activity or nitrogen-fixation capacity. These findings suggest that brassinosteroids are negative regulators of infection but positive regulators of nodule initiation. Furthermore, brassinosteroids do not appear to be essential for nodule organogenesis or function. Given the influence of brassinosteroids on discreet stages of nodulation but not nodule function, manipulation of brassinosteroids may be an interesting avenue for future research on the optimisation of nodulation.},
}
@article {pmid32995702,
year = {2020},
author = {Bürger, M and Chory, J},
title = {In-silico analysis of the strigolactone ligand-receptor system.},
journal = {Plant direct},
volume = {4},
number = {9},
pages = {e00263},
pmid = {32995702},
issn = {2475-4455},
support = {R01 GM052413/GM/NIGMS NIH HHS/United States ; R01 GM094428/GM/NIGMS NIH HHS/United States ; R35 GM122604/GM/NIGMS NIH HHS/United States ; },
abstract = {Strigolactones (SLs) are a diverse class of butenolide-bearing plant hormones associated with several processes of major agricultural concern. SLs initiate symbiosis between plants and arbuscular mycorrhizal fungi, cause germination of crop-devastating parasitic plants, and inhibit shoot branching in vascular plants. SLs are perceived by dual receptor-hydrolase proteins, and capturing the intact ligand inside the receptor remains a key challenge for structural biologists. In addition, many discovered SLs are hard to obtain and too unstable to work with. In a computer-based approach, we investigated the interaction of 20 different SL molecules with nine crystal structures of SL receptors. Our results suggest an important role of the active site for ligand binding and orientation, and that the parasitic plant Striga hermonthica has developed both promiscuous and type-specific SL receptors as part of its host recognition strategy.},
}
@article {pmid32994291,
year = {2020},
author = {Lu, Y and Jiang, J and Zhao, H and Han, X and Xiang, Y and Zhou, W},
title = {Clade-Specific Sterol Metabolites in Dinoflagellate Endosymbionts Are Associated with Coral Bleaching in Response to Environmental Cues.},
journal = {mSystems},
volume = {5},
number = {5},
pages = {},
pmid = {32994291},
issn = {2379-5077},
abstract = {Cnidarians cannot synthesize sterols (which play essential roles in growth and development) de novo but often use sterols acquired from endosymbiotic dinoflagellates. While sterol availability can impact the mutualistic interaction between coral host and algal symbiont, the biosynthetic pathways (in the dinoflagellate endosymbionts) and functional roles of sterols in these symbioses are poorly understood. In this study, we found that itraconazole, which perturbs sterol metabolism by inhibiting the sterol 14-demethylase CYP51 in dinoflagellates, induces bleaching of the anemone Heteractis crispa and that bleaching perturbs sterol metabolism of the dinoflagellate. While Symbiodiniaceae have clade-specific sterol metabolites, they share features of the common sterol biosynthetic pathway but with distinct architecture and substrate specificity features of participating enzymes. Tracking sterol profiles and transcripts of enzymes involved in sterol biosynthesis across time in response to different environmental cues revealed similarities and idiosyncratic features of sterol synthesis in the endosymbiont Breviolum minutum Exposure of algal cultures to high levels of light, heat, and acidification led to alterations in sterol synthesis, including blocks through downregulation of squalene synthase transcript levels accompanied by marked growth reductions.IMPORTANCE These results indicate that sterol metabolites in Symbiodiniaceae are clade specific, that their biosynthetic pathways share architectural and substrate specificity features with those of animals and plants, and that environmental stress-specific perturbation of sterol biosynthesis in dinoflagellates can impair a key mutualistic partnership for healthy reefs.},
}
@article {pmid32994029,
year = {2020},
author = {Shitole, AA and Sharma, N and Giram, P and Khandwekar, A and Baruah, M and Garnaik, B and Koratkar, S},
title = {LHRH-conjugated, PEGylated, poly-lactide-co-glycolide nanocapsules for targeted delivery of combinational chemotherapeutic drugs Docetaxel and Quercetin for prostate cancer.},
journal = {Materials science & engineering. C, Materials for biological applications},
volume = {114},
number = {},
pages = {111035},
doi = {10.1016/j.msec.2020.111035},
pmid = {32994029},
issn = {1873-0191},
abstract = {One of the major challenges in effective cancer chemotherapy is the severe systemic cytotoxicities of anticancer drugs on healthy tissues. The present study reports chemically modified polymeric nanocapsules (NCs) encapsulating combination of chemotherapeutic drugs Docetaxel (DTX) and Quercetin (QU) for its active targeting to prostate cancer (PCa). The active targeting was achieved by conjugating Luteinizing-hormone-releasing hormone (LHRH) ligand to poly-lactide-co-glycolide (PLGA) using polyethylene glycol (PEG) as a spacer. The structure of the conjugates was characterized and confirmed using 1H NMR and ATR-FTIR. The drug encapsulated NCs showed a homogenous size distribution with their size ranging between 120 and 150 nm, and exhibited a negative zeta potential in the range of -20 to -40 mV. The in vitro release studies highlighted the sustained drug release pattern from the respective NCs; while the PEG coating to polymeric NCs provided serum stability to the NCs. The in vitro biological evaluation of the NCs was conducted using PC-3 and LNCaP cell lines. The results of the cellular uptake studies showed a significantly higher untake of the LHRH targeted NCs, while the LHRH-targeted-PEGylated DTX: QU NCs exhibited higher caspase-3 activity. The cell viability assay results showed the enhanced cell inhibition activity of the combinatorial DTX: QU when compared to individual DTX. Further, higher cell cytotoxicity was achieved by LHRH-targeted DTX: QU NCs as compared to their free-form or non-targeted NCs. Finally, the results of in vivo tumor localization and in vivo antitumor activity studies complimented and upheld the in vitro results, demonstrating the beneficial role of PLGA-PEG-LHRH NCs encapsulating combination of DTX and QU in combating prostate cancer (PCa).},
}
@article {pmid32993496,
year = {2020},
author = {Kono, M and Kon, Y and Ohmura, Y and Satta, Y and Terai, Y},
title = {In vitro resynthesis of lichenization reveals the genetic background of symbiosis-specific fungal-algal interaction in Usnea hakonensis.},
journal = {BMC genomics},
volume = {21},
number = {1},
pages = {671},
pmid = {32993496},
issn = {1471-2164},
abstract = {BACKGROUND: Symbiosis is central to ecosystems and has been an important driving force of the diversity of life. Close and long-term interactions are known to develop cooperative molecular mechanisms between the symbiotic partners and have often given them new functions as symbiotic entities. In lichen symbiosis, mutualistic relationships between lichen-forming fungi and algae and/or cyanobacteria produce unique features that make lichens adaptive to a wide range of environments. Although the morphological, physiological, and ecological uniqueness of lichens has been described for more than a century, the genetic mechanisms underlying this symbiosis are still poorly known.
RESULTS: This study investigated the fungal-algal interaction specific to the lichen symbiosis using Usnea hakonensis as a model system. The whole genome of U. hakonensis, the fungal partner, was sequenced by using a culture isolated from a natural lichen thallus. Isolated cultures of the fungal and the algal partners were co-cultured in vitro for 3 months, and thalli were successfully resynthesized as visible protrusions. Transcriptomes of resynthesized and natural thalli (symbiotic states) were compared to that of isolated cultures (non-symbiotic state). Sets of fungal and algal genes up-regulated in both symbiotic states were identified as symbiosis-related genes.
CONCLUSION: From predicted functions of these genes, we identified genetic association with two key features fundamental to the symbiotic lifestyle in lichens. The first is establishment of a fungal symbiotic interface: (a) modification of cell walls at fungal-algal contact sites; and (b) production of a hydrophobic layer that ensheaths fungal and algal cells;. The second is symbiosis-specific nutrient flow: (a) the algal supply of photosynthetic product to the fungus; and (b) the fungal supply of phosphorous and nitrogen compounds to the alga. Since both features are widespread among lichens, our result may indicate important facets of the genetic basis of the lichen symbiosis.},
}
@article {pmid32993486,
year = {2020},
author = {Koch, TL and Grimmelikhuijzen, CJP},
title = {A comparative genomics study of neuropeptide genes in the cnidarian subclasses Hexacorallia and Ceriantharia.},
journal = {BMC genomics},
volume = {21},
number = {1},
pages = {666},
pmid = {32993486},
issn = {1471-2164},
support = {7014-0008B//Natur og Univers, Det Frie Forskningsråd/ ; N/A//Carlsbergfondet/ ; },
abstract = {BACKGROUND: Nervous systems originated before the split of Proto- and Deuterostomia, more than 600 million years ago. Four animal phyla (Cnidaria, Placozoa, Ctenophora, Porifera) diverged before this split and studying these phyla could give us important information on the evolution of the nervous system. Here, we have annotated the neuropeptide preprohormone genes of twenty species belonging to the subclass Hexacorallia or Ceriantharia (Anthozoa: Cnidaria), using thirty-seven publicly accessible genome or transcriptome databases. Studying hexacorals is important, because they are versatile laboratory models for development (e.g., Nematostella vectensis) and symbiosis (e.g., Exaiptasia diaphana) and also are prominent reef-builders.
RESULTS: We found that each hexacoral or ceriantharian species contains five to ten neuropeptide preprohormone genes. Many of these preprohormones contain multiple copies of immature neuropeptides, which can be up to 50 copies of identical or similar neuropeptide sequences. We also discovered preprohormones that only contained one neuropeptide sequence positioned directly after the signal sequence. Examples of them are neuropeptides that terminate with the sequence RWamide (the Antho-RWamides). Most neuropeptide sequences are N-terminally protected by pyroglutamyl (pQ) or one or more prolyl residues, while they are C-terminally protected by an amide group. Previously, we isolated and sequenced small neuropeptides from hexacorals that were N-terminally protected by an unusual L-3-phenyllactyl group. In our current analysis, we found that these N-phenyllactyl-peptides are derived from N-phenylalanyl-peptides located directly after the signal sequence of the preprohormone. The N-phenyllactyl- peptides appear to be confined to the hexacorallian order Actiniaria and do not occur in other cnidarians. On the other hand, (1) the neuropeptide Antho-RFamide (pQGRFamide); (2) peptides with the C-terminal sequence GLWamide; and (3) tetrapeptides with the X1PRX2amide consensus sequence (most frequently GPRGamide) are ubiquitous in Hexacorallia.
CONCLUSIONS: We found GRFamide, GLWamide, and X1PRX2amide peptides in all tested Hexacorallia. Previously, we discovered these three neuropeptide classes also in Cubozoa, Scyphozoa, and Staurozoa, indicating that these neuropeptides originated in the common cnidarian ancestor and are evolutionarily ancient. In addition to these ubiquitous neuropeptides, other neuropeptides appear to be confined to specific cnidarian orders or subclasses.},
}
@article {pmid32993305,
year = {2020},
author = {Guarner, F},
title = {[Symbiosis in the human gastrointestinal tract].},
journal = {Nutricion hospitalaria},
volume = {},
number = {},
pages = {},
doi = {10.20960/nh.03354},
pmid = {32993305},
issn = {1699-5198},
abstract = {The human body is a planet populated by myriads of microorganisms all over its surface and in cavities connected to the outside. Experimental and clinical research is showing that microbial colonizers are a functional and essential part of the human organism. The microbial ecosystem, which is housed in the gastrointestinal tract, provides a "metagenome": genes and additional functions to the genetic resources of the species, which are involved in multiple physiological processes (somatic development, nutrition, immunity, etc.). The human intestine houses lymphoid structures specialized in the induction and regulation of adaptive immunity, and the interaction of the intestinal microbiota with the immune system of the digestive mucosa plays a key role for the individual's homeostasis with the outside world. Some chronic non-communicable inflammatory diseases in developed society are associated with dysbiosis: loss of species richness in the gut microbiota and deviation from the ancestral microbial environment. Generating and maintaining diversity in the gut microbiota is a new clinical goal for health promotion and disease prevention.},
}
@article {pmid32993063,
year = {2020},
author = {Martins, F and Gonçalves, LG and Pojo, M and Serpa, J},
title = {Take Advantage of Glutamine Anaplerosis, the Kernel of the Metabolic Rewiring in Malignant Gliomas.},
journal = {Biomolecules},
volume = {10},
number = {10},
pages = {},
pmid = {32993063},
issn = {2218-273X},
abstract = {Glutamine is a non-essential amino acid that plays a key role in the metabolism of proliferating cells including neoplastic cells. In the central nervous system (CNS), glutamine metabolism is particularly relevant, because the glutamine-glutamate cycle is a way of controlling the production of glutamate-derived neurotransmitters by tightly regulating the bioavailability of the amino acids in a neuron-astrocyte metabolic symbiosis-dependent manner. Glutamine-related metabolic adjustments have been reported in several CNS malignancies including malignant gliomas that are considered 'glutamine addicted'. In these tumors, glutamine becomes an essential amino acid preferentially used in energy and biomass production including glutathione (GSH) generation, which is crucial in oxidative stress control. Therefore, in this review, we will highlight the metabolic remodeling that gliomas undergo, focusing on glutamine metabolism. We will address some therapeutic regimens including novel research attempts to target glutamine metabolism and a brief update of diagnosis strategies that take advantage of this altered profile. A better understanding of malignant glioma cell metabolism will help in the identification of new molecular targets and the design of new therapies.},
}
@article {pmid32991980,
year = {2020},
author = {Dumasia, NP and Pethe, PS},
title = {Pancreas development and the Polycomb group protein complexes.},
journal = {Mechanisms of development},
volume = {164},
number = {},
pages = {103647},
doi = {10.1016/j.mod.2020.103647},
pmid = {32991980},
issn = {1872-6356},
abstract = {The dual nature of pancreatic tissue permits both endocrine and exocrine functions. Enzymatic secretions by the exocrine pancreas help digestive processes while the pancreatic hormones regulate glucose homeostasis and energy metabolism. Pancreas organogenesis is defined by a conserved array of signaling pathways that act on common gut progenitors to bring about the generation of diverse cell types. Multiple cellular processes characterize development of the mature organ. These processes are mediated by signaling pathways that regulate lineage-specific transcription factors and chromatin modifications guiding long-term gene expression programs. The chromatin landscape is altered chiefly by DNA or histone modifications, chromatin remodelers, and non-coding RNAs. Amongst histone modifiers, several studies have identified Polycomb group (PcG) proteins as crucial determinants mediating transcriptional repression of genes involved in developmental processes. Although PcG-mediated chromatin modifications define cellular transitions and influence cell identity of multipotent progenitors, much remains to be understood regarding coordination between extracellular signals and their impact on Polycomb functions during the pancreas lineage progression. In this review, we discuss interactions between sequence-specific DNA binding proteins and chromatin regulators underlying pancreas development and insulin producing β-cells, with particular focus on Polycomb group proteins. Understanding such basic molecular mechanisms would improve current strategies for stem cell-based differentiation while also help elucidate the pathogenesis of several pancreas-related maladies, including diabetes and pancreatic cancer.},
}
@article {pmid32990949,
year = {2020},
author = {Liu, M and Jia, N and Li, X and Liu, R and Xie, Q and Murray, JD and Downie, JA and Xie, F},
title = {CERBERUS is critical for stabilization of VAPYRIN during rhizobial infection in Lotus japonicus.},
journal = {The New phytologist},
volume = {},
number = {},
pages = {},
doi = {10.1111/nph.16973},
pmid = {32990949},
issn = {1469-8137},
support = {153D31KYSB20160074//Chinese Academy of Sciences/ ; XDB27040208//Chinese Academy of Sciences/ ; 31700207//National Natural Science Foundation of China/ ; 2017A0407-14//State Key Laboratory of Plant Genomics/ ; 2016YFA0500500//The National Key R&D Program of China/ ; },
abstract = {CERBERUS (also known as LIN) and VAPYRIN (VPY) are essential for infection of legumes by rhizobia and arbuscular mycorrhizal fungi (AMF). Medicago truncatula LIN (MtLIN) was reported to interact with MtVPY, but the significance of this interaction is unclear and the function of VPY in Lotus japonicus has not been studied. We demonstrate that CERBERUS has auto-ubiquitination activity in vitro and is localized within distinct motile puncta in L. japonicus root hairs and in Nicotiana benthamiana leaves. CERBERUS colocalized with the trans-Golgi network/early endosome markers. In L. japonicus, two VPY orthologs (LjVPY1 and LjVPY2) were identified. CERBERUS interacted with and colocalized with both LjVPY1 and LjVPY2. Co-expression of CERBERUS with LjVPY1 or LjVPY2 in N. benthamiana led to increased protein levels of LjVPY1 and LjVPY2, which accumulated as mobile punctate bodies in the cytoplasm. Conversely, LjVPY2 protein levels decreased in cerberus roots after rhizobial inoculation. Mutant analysis indicates that LjVPY1 and LjVPY2 are required for rhizobial infection and colonization by AMF. Our data suggest that CERBERUS stabilizes LjVPY1 and LjVPY2 within the trans-Golgi network/early endosome, where they might function to regulate endocytic trafficking and/or the formation or recycling of signaling complexes during rhizobial and AMF symbiosis.},
}
@article {pmid32990642,
year = {2020},
author = {Krol, E and Schäper, S and Becker, A},
title = {Cyclic di-GMP signaling controlling the free-living lifestyle of alpha-proteobacterial rhizobia.},
journal = {Biological chemistry},
volume = {401},
number = {12},
pages = {1335-1348},
doi = {10.1515/hsz-2020-0232},
pmid = {32990642},
issn = {1437-4315},
abstract = {Cyclic-di-GMP (c-di-GMP) is a ubiquitous bacterial second messenger which has been associated with a motile to sessile lifestyle switch in many bacteria. Here, we review recent insights into c-di-GMP regulated processes related to environmental adaptations in alphaproteobacterial rhizobia, which are diazotrophic bacteria capable of fixing nitrogen in symbiosis with their leguminous host plants. The review centers on Sinorhizobium meliloti, which in the recent years was intensively studied for its c-di-GMP regulatory network.},
}
@article {pmid32988416,
year = {2020},
author = {Brown, SP and Grillo, MA and Podowski, JC and Heath, KD},
title = {Soil origin and plant genotype structure distinct microbiome compartments in the model legume Medicago truncatula.},
journal = {Microbiome},
volume = {8},
number = {1},
pages = {139},
doi = {10.1186/s40168-020-00915-9},
pmid = {32988416},
issn = {2049-2618},
abstract = {BACKGROUND: Understanding the genetic and environmental factors that structure plant microbiomes is necessary for leveraging these interactions to address critical needs in agriculture, conservation, and sustainability. Legumes, which form root nodule symbioses with nitrogen-fixing rhizobia, have served as model plants for understanding the genetics and evolution of beneficial plant-microbe interactions for decades, and thus have added value as models of plant-microbiome interactions. Here we use a common garden experiment with 16S rRNA gene amplicon and shotgun metagenomic sequencing to study the drivers of microbiome diversity and composition in three genotypes of the model legume Medicago truncatula grown in two native soil communities.
RESULTS: Bacterial diversity decreased between external (rhizosphere) and internal plant compartments (root endosphere, nodule endosphere, and leaf endosphere). Community composition was shaped by strong compartment × soil origin and compartment × plant genotype interactions, driven by significant soil origin effects in the rhizosphere and significant plant genotype effects in the root endosphere. Nevertheless, all compartments were dominated by Ensifer, the genus of rhizobia that forms root nodule symbiosis with M. truncatula, and additional shotgun metagenomic sequencing suggests that the nodulating Ensifer were not genetically distinguishable from those elsewhere in the plant. We also identify a handful of OTUs that are common in nodule tissues, which are likely colonized from the root endosphere.
CONCLUSIONS: Our results demonstrate strong host filtering effects, with rhizospheres driven by soil origin and internal plant compartments driven by host genetics, and identify several key nodule-inhabiting taxa that coexist with rhizobia in the native range. Our results set the stage for future functional genetic experiments aimed at expanding our pairwise understanding of legume-rhizobium symbiosis toward a more mechanistic understanding of plant microbiomes. Video Abstract.},
}
@article {pmid32987347,
year = {2020},
author = {Li, X and Chertow, M and Guo, S and Johnson, E and Jiang, D},
title = {Estimating non-hazardous industrial waste generation by sector, location, and year in the United States: A methodological framework and case example of spent foundry sand.},
journal = {Waste management (New York, N.Y.)},
volume = {118},
number = {},
pages = {563-572},
doi = {10.1016/j.wasman.2020.08.056},
pmid = {32987347},
issn = {1879-2456},
mesh = {*Hazardous Waste ; Industrial Waste ; Industry ; Sand ; United States ; *Waste Management ; },
abstract = {Non-hazardous industrial waste (NHIW), primarily consisting of manufacturing process residues, has long been overlooked in waste reporting, regulation, and reuse. Limited information about NHIW generation with spatial and sectoral details has impeded the systematization of reuse efforts to move towards a resource-efficient economy. In this article, we develop a methodological framework that makes the best use of fragmented and limited observational data to infer the confidence intervals of NHIW generation by sector, location, and year across the United States. The framework decomposes the quantity of NHIW into two factors: the activity level (economic output) and the waste intensity factor (waste tonnage generated per unit of output). It statistically infers the probability distribution of the waste intensity factor and extrapolates waste tonnages to the entire country. In our demonstrative application of the method, we provide an updated estimate for spent foundry sand and find that its total amount in the United States decreased from 2.2-7.1 million tons in 2004 to 1.4-4.7 million tons in 2014. The spatial distribution, however, was highly uneven, with over 90% of the waste generated in 10% of the counties, indicating great variations in reuse potentials and benefits among regions. Our methodological framework makes a significant departure from existing estimations that usually rely on averaging limited observations or expert judgments biased by subjectivity. Detailing spatial and sectoral distributions and temporal trends in NHIW generation and reuse benefits, our study could inform more systematic strategies on waste and materials management to build a circular economy.},
}
@article {pmid32985595,
year = {2020},
author = {Campo, S and San Segundo, B},
title = {Systemic induction of phosphatidylinositol-based signaling in leaves of arbuscular mycorrhizal rice plants.},
journal = {Scientific reports},
volume = {10},
number = {1},
pages = {15896},
pmid = {32985595},
issn = {2045-2322},
mesh = {Fungi/metabolism ; Gene Expression Regulation, Plant ; Mycorrhizae/*metabolism ; Oryza/*metabolism/microbiology ; Phosphatidylinositols/*metabolism ; Plant Leaves/*metabolism ; Plant Roots/metabolism ; Symbiosis/*physiology ; },
abstract = {Most land plants form beneficial associations with arbuscular mycorrhizal (AM) fungi which improves mineral nutrition, mainly phosphorus, in the host plant in exchange for photosynthetically fixed carbon. Most of our knowledge on the AM symbiosis derives from dicotyledonous species. We show that inoculation with the AM fungus Funneliformis mosseae stimulates growth and increases Pi content in leaves of rice plants (O. sativa, cv Loto, ssp japonica). Although rice is a host for AM fungi, the systemic transcriptional responses to AM inoculation, and molecular mechanisms underlying AM symbiosis in rice remain largely elusive. Transcriptomic analysis identified genes systemically regulated in leaves of mycorrhizal rice plants, including genes with functions associated with the biosynthesis of phospholipids and non-phosphorus lipids (up-regulated and down-regulated, respectively). A coordinated regulation of genes involved in the biosynthesis of phospholipids and inositol polyphosphates, and genes involved in hormone biosynthesis and signaling (jasmonic acid, ethylene) occurs in leaves of mycorrhizal rice. Members of gene families playing a role in phosphate starvation responses and remobilization of Pi were down-regulated in leaves of mycorrhizal rice. These results demonstrated that the AM symbiosis is accompanied by systemic transcriptional responses, which are potentially important to maintain a stable symbiotic relationship in rice plants.},
}
@article {pmid32985530,
year = {2020},
author = {Carradec, Q and Poulain, J and Boissin, E and Hume, BCC and Voolstra, CR and Ziegler, M and Engelen, S and Cruaud, C and Planes, S and Wincker, P},
title = {A framework for in situ molecular characterization of coral holobionts using nanopore sequencing.},
journal = {Scientific reports},
volume = {10},
number = {1},
pages = {15893},
pmid = {32985530},
issn = {2045-2322},
mesh = {Animals ; Anthozoa/*microbiology ; Bacteria/*genetics ; *Coral Reefs ; Microbiota/*genetics ; Nanopore Sequencing ; Symbiosis ; },
abstract = {Molecular characterization of the coral host and the microbial assemblages associated with it (referred to as the coral holobiont) is currently undertaken via marker gene sequencing. This requires bulky instruments and controlled laboratory conditions which are impractical for environmental experiments in remote areas. Recent advances in sequencing technologies now permit rapid sequencing in the field; however, development of specific protocols and pipelines for the effective processing of complex microbial systems are currently lacking. Here, we used a combination of 3 marker genes targeting the coral animal host, its symbiotic alga, and the associated bacterial microbiome to characterize 60 coral colonies collected and processed in situ, during the Tara Pacific expedition. We used Oxford Nanopore Technologies to sequence marker gene amplicons and developed bioinformatics pipelines to analyze nanopore reads on a laptop, obtaining results in less than 24 h. Reef scale network analysis of coral-associated bacteria reveals broadly distributed taxa, as well as host-specific associations. Protocols and tools used in this work may be applicable for rapid coral holobiont surveys, immediate adaptation of sampling strategy in the field, and to make informed and timely decisions in the context of the current challenges affecting coral reefs worldwide.},
}
@article {pmid32985445,
year = {2019},
author = {Ansari, H and Yeravdekar, R},
title = {Respectful maternity care: A national landscape review.},
journal = {The National medical journal of India},
volume = {32},
number = {5},
pages = {290-293},
doi = {10.4103/0970-258X.295957},
pmid = {32985445},
issn = {0970-258X},
mesh = {Attitude of Health Personnel ; Confidentiality ; *Delivery, Obstetric ; Economic Status ; Empathy ; Female ; *Health Policy ; Humans ; India ; Literacy ; *Maternal Health Services ; Patient Participation ; Personal Autonomy ; Pregnancy ; Pregnant Women ; Privacy ; *Professional-Patient Relations ; Quality of Health Care ; *Respect ; Vulnerable Populations ; },
abstract = {Respectful maternity care is a fundamental right of every childbearing woman. It contributes to ensuring a positive outcome for mothers as well as newborns, and aims to address health inequalities. However, studies have reported a high prevalence of disrespect and abuse in India, and have shown that the quality of care has been overlooked at all levels including research, policy, programme and practice. The lack of respectful maternity care results in failure in accessing institutional services. Thus, it is essential to design context-specific and evidence-based interventions as well as formulate policies and programmes to reduce disrespectful maternity care.},
}
@article {pmid32984471,
year = {2020},
author = {Kashkak, ES and Kataev, VY and Khlopko, YA and Budagaeva, VG and Danilova, EV and Oorzhak, US and Dagurova, OP and Plotnikov, AO},
title = {Data on draft genome sequence of stenotrophomonas sp. SAM-B isolated from a mineral cold spring located in Tyva, southern Siberia.},
journal = {Data in brief},
volume = {32},
number = {},
pages = {106278},
pmid = {32984471},
issn = {2352-3409},
abstract = {Stenotrophomonas sp. SAM-B was isolated from Uzharlyg Mineral Cold Spring, Samagaltay Settlement, Republic of Tyva (Southern Siberia), Russian Federation. A whole genome sequencing of Stenotrophomonas sp. SAM-B was performed using an Illumina MiSeq platform. The resulting draft genome contains 4,253,956 bp with 66.48% GC-content and 71 contigs; the longest contig contains 968,648 bp, and the N50 has a length of 401,736 bp. The genome includes 3816 protein-coding genes, among which 23 are responsible for protein degradation, 65 are associated with stress response, and 31 are associated with virulence, disease, and defense, including beta-lactamase and resistance to fluoroquinolones. The genome data on the SAM-B strain provides fundamental knowledge that would allow a better understanding of the microorganisms inhabiting cold water environments. Moreover, the results of the genome annotation indicated that diverse metabolic pathways are encoded in the genome of the SAM-B strain and that it has biotechnological potential. The draft genome sequence of Stenotrophomonas sp. SAM-B has been deposited in DDBJ/ENA/GenBank under the accession number JABBXB000000000; the accession number of the genome sequence referred to in this paper is JABBXB010000000.},
}
@article {pmid32979241,
year = {2020},
author = {Banerji, R and Kanojiya, P and Patil, A and Saroj, SD},
title = {Polyamines in the virulence of bacterial pathogens of respiratory tract.},
journal = {Molecular oral microbiology},
volume = {},
number = {},
pages = {},
doi = {10.1111/omi.12315},
pmid = {32979241},
issn = {2041-1014},
support = {BT/RLF/Re-entry/41/2015//Department of Biotechnology , Ministry of Science and Technology/ ; SIU/SCRI/MJRP-Approval/2019/1556//Major research project grant of Symbiosis International (Deemed University)/ ; 598515-EPP-1-2018-1-IN-EPPKA2-CBHE-JP//ERASMUS+/ ; },
abstract = {Polyamines are positively charged hydrocarbons that are essential for the growth and cellular maintenance in prokaryotes and eukaryotes. Polyamines have been demonstrated to play a role in bacterial pathogenicity and biofilm formation. However, the role of extracellular polyamines as a signaling molecule in the regulation of virulence is not investigated in detail. The bacterial pathogens residing in the respiratory tract remain asymptomatic for an extended period; however, the factors that lead to symptomatic behavior are poorly understood. Further investigation to understand the relation between the host-secreted factors and virulence of pathogenic bacteria in the respiratory tract may provide insights into the pathogenesis of respiratory tract infections. Polyamines produced within the bacterial cell are generally sequestered. Therefore, the pool of extracellular polyamines formed by secretion of the commensals and the host may be one of the signaling molecules that might contribute toward the alterations in the expression of virulence factors in bacterial pathogens. Besides, convergent mechanisms of polyamine biosynthesis do exist across the border of species and genus level. Also, several novel polyamine transporters in the host and bacteria remain yet to be identified. The review focuses on the role of polyamines in the expression of virulence phenotypes and biofilm formation of the respiratory tract pathogens.},
}
@article {pmid32979167,
year = {2020},
author = {Nivedita, and Gazara, RK and Khan, S and Iqrar, S and Ashrafi, K and Abdin, MZ},
title = {Comparative transcriptome profiling of rice colonized with beneficial endophyte, Piriformospora indica, under high salinity environment.},
journal = {Molecular biology reports},
volume = {47},
number = {10},
pages = {7655-7673},
doi = {10.1007/s11033-020-05839-z},
pmid = {32979167},
issn = {1573-4978},
support = {SB/YS/LS-111/2014//Science and Engineering Research Board/ ; },
abstract = {The salinity stress tolerance in plants has been studied enormously, reflecting its agronomic relevance. Despite the extensive research, limited success has been achieved in relation to the plant tolerance mechanism. The beneficial interaction between Piriformospora indica and rice could essentially improve the performance of the plant during salt stress. In this study, the transcriptomic data between P. indica treated and untreated rice roots were compared under control and salt stress conditions. Overall, 661 salt-responsive differentially expressed genes (DEGs) were detected with 161 up- and 500 down-regulated genes in all comparison groups. Gene ontology analyses indicated the DEGs were mainly enriched in "auxin-activated signaling pathway", "water channel activity", "integral component of plasma membrane", "stress responses", and "metabolic processes". Kyoto Encyclopedia of Genes and Genomes pathway analysis revealed that the DEGs were primarily related to "Zeatin biosynthesis", "Fatty acid elongation", "Carotenoid biosynthesis", and "Biosynthesis of secondary metabolites". Particularly, genes related to cell wall modifying enzymes (e.g. invertase/pectin methylesterase inhibitor protein and arabinogalactans), phytohormones (e.g. Auxin-responsive Aux/IAA gene family, ent-kaurene synthase, and 12-oxophytodienoate reductase) and receptor-like kinases (e.g. AGC kinase and receptor protein kinase) were induced in P. indica colonized rice under salt stress condition. The differential expression of these genes implies that the coordination between hormonal crosstalk, signaling, and cell wall dynamics contributes to the higher growth and tolerance in P. indica-inoculated rice. Our results offer a valuable resource for future functional studies on salt-responsive genes that should improve the resilience and adaptation of rice against salt stress.},
}
@article {pmid32978812,
year = {2020},
author = {Shrestha, A and Zhong, S and Therrien, J and Huebert, T and Sato, S and Mun, T and Andersen, SU and Stougaard, J and Lepage, A and Niebel, A and Ross, L and Szczyglowski, K},
title = {Lotus japonicus Nuclear Factor YA1, a nodule emergence stage-specific regulator of auxin signalling.},
journal = {The New phytologist},
volume = {},
number = {},
pages = {},
doi = {10.1111/nph.16950},
pmid = {32978812},
issn = {1469-8137},
support = {CE20-012//Agence Nationale de la Recherche/ ; DNRF79//Danish National Research Foundation/ ; 3277A01//National Science and Engineering Research Council of Canada/ ; //Agriculture and Agri-Food Canada Crop Genomics Initiative/ ; ANR-10-LABX-41//Laboratoire d'Excellence (LABEX)" TULIP/ ; },
abstract = {Organogenesis of legume root nodules begins with the nodulation factor-dependent stimulation of compatible root cells to initiate divisions, signifying an early nodule primordium formation event. This is followed by cellular differentiation, including cell expansion and vascular bundle formation, and we previously showed that Lotus japonicus NF-YA1 is essential for this process, presumably by regulating three members of the SHORT INTERNODES/STYLISH (STY) transcription factor gene family. In this study, we used combined genetics, genomics and cell biology approaches to characterize the role of STY genes during root nodule formation and to test a hypothesis that they mediate nodule development by stimulating auxin signalling. We show here that L. japonicus STYs are required for nodule emergence. This is attributed to the NF-YA1-dependent regulatory cascade, comprising STY genes and their downstream targets, YUCCA1 and YUCCA11, involved in a local auxin biosynthesis at the post-initial cell division stage. An analogous NF-YA1/STY regulatory module seems to operate in Medicago truncatula in association with the indeterminate nodule patterning. Our data define L. japonicus and M. truncatula NF-YA1 genes as important nodule emergence stage-specific regulators of auxin signalling while indicating that the inductive stage and subsequent formation of early nodule primordia are mediated through an independent mechanism(s).},
}
@article {pmid32978315,
year = {2020},
author = {Bailey, GF and Coelho, JC and Poole, AZ},
title = {Differential expression of Exaiptasia pallida GIMAP genes upon induction of apoptosis and autophagy suggests a potential role in cnidarian symbiosis and disease.},
journal = {The Journal of experimental biology},
volume = {223},
number = {Pt 21},
pages = {},
doi = {10.1242/jeb.229906},
pmid = {32978315},
issn = {1477-9145},
abstract = {Coral reefs, one of the world's most productive and diverse ecosystems, are currently threatened by a variety of stressors that result in increased prevalence of both bleaching and disease. Therefore, understanding the molecular mechanisms involved in these responses is critical to mitigate future damage to the reefs. One group of genes that is potentially involved in cnidarian immunity and symbiosis is GTPases of immunity associated proteins (GIMAP). In vertebrates, this family of proteins is involved in regulating the fate of developing lymphocytes and interacts with proteins involved in apoptosis and autophagy. As apoptosis, autophagy and immunity have previously been shown to be involved in cnidarian symbiosis and disease, the goal of this research was to determine the role of cnidarian GIMAPs in these processes using the anemone Exaiptasia pallida To do so, GIMAP genes were characterized in the E. pallida genome and changes in gene expression were measured using qPCR in response to chemical induction of apoptosis, autophagy and treatment with the immune stimulant lipopolysaccharide (LPS) in both aposymbiotic and symbiotic anemones. The results revealed four GIMAP-like genes in E. pallida, referred to as Ep_GIMAPs Induction of apoptosis and autophagy resulted in a general downregulation of Ep_GIMAPs, but no significant changes were observed in response to LPS treatment. This indicates that Ep_GIMAPs may be involved in the regulation of apoptosis and autophagy, and therefore could play a role in cnidarian-dinoflagellate symbiosis. Overall, these results increase our knowledge on the function of GIMAPs in a basal metazoan.},
}
@article {pmid32975913,
year = {2020},
author = {Christensen, DG and Tepavčević, J and Visick, KL},
title = {Genetic Manipulation of Vibrio fischeri.},
journal = {Current protocols in microbiology},
volume = {59},
number = {1},
pages = {e115},
doi = {10.1002/cpmc.115},
pmid = {32975913},
issn = {1934-8533},
support = {R35 GM130355/GM/NIGMS NIH HHS/United States ; 1R35 GM130355/GF/NIH HHS/United States ; },
abstract = {Vibrio fischeri is a nonpathogenic organism related to pathogenic Vibrio species. The bacterium has been used as a model organism to study symbiosis in the context of its association with its host, the Hawaiian bobtail squid Euprymna scolopes. The genetic tractability of this bacterium has facilitated the mapping of pathways that mediate interactions between these organisms. The protocols included here describe methods for genetic manipulation of V. fischeri. Following these protocols, the researcher will be able to introduce linear DNA via transformation to make chromosomal mutations, to introduce plasmid DNA via conjugation and subsequently eliminate unstable plasmids, to eliminate antibiotic resistance cassettes from the chromosome, and to randomly or specifically mutagenize V. fischeri with transposons. © 2020 Wiley Periodicals LLC. Basic Protocol 1: Transformation of V. fischeri with linear DNA Basic Protocol 2: Plasmid transfer into V. fischeri via conjugation Support Protocol 1: Removing FRT-flanked antibiotic resistance cassettes from the V. fischeri genome Support Protocol 2: Eliminating unstable plasmids from V. fischeri Alternate Protocol 1: Introduction of exogenous DNA using a suicide plasmid Alternate Protocol 2: Site-specific transposon insertion using a suicide plasmid Alternate Protocol 3: Random transposon mutagenesis using a suicide plasmid.},
}
@article {pmid32974256,
year = {2020},
author = {Duperron, S and Halary, S and Gallet, A and Marie, B},
title = {Microbiome-Aware Ecotoxicology of Organisms: Relevance, Pitfalls, and Challenges.},
journal = {Frontiers in public health},
volume = {8},
number = {},
pages = {407},
pmid = {32974256},
issn = {2296-2565},
abstract = {Over the last 15 years, the advent of high-throughput "omics" techniques has revealed the multiple roles and interactions occurring among hosts, their microbial partners and their environment. This microbiome revolution has radically changed our views of biology, evolution, and individuality. Sitting at the interface between a host and its environment, the microbiome is a relevant yet understudied compartment for ecotoxicology research. Various recent works confirm that the microbiome reacts to and interacts with contaminants, with consequences for hosts and ecosystems. In this paper, we thus advocate for the development of a "microbiome-aware ecotoxicology" of organisms. We emphasize its relevance and discuss important conceptual and technical pitfalls associated with study design and interpretation. We identify topics such as functionality, quantification, temporality, resilience, interactions, and prediction as major challenges and promising venues for microbiome research applied to ecotoxicology.},
}
@article {pmid32972090,
year = {2020},
author = {Tanaka, H and Sodeyama, F and Kohtsuka, H},
title = {A New Species of Ostracod (Crustacea) Associated with a Feather Star: First Report of Ostracoda from Crinoidea.},
journal = {Zoological science},
volume = {37},
number = {5},
pages = {496-503},
doi = {10.2108/zs200032},
pmid = {32972090},
issn = {0289-0003},
abstract = {We describe Obesostoma crinophilum sp. nov. (Ostracoda: Podocopida: Paradoxostomatidae) obtained from the body surface of the feather star Antedon serrata A. H. Clark, 1908 (Crinoidea: Comatulida: Antedonidae). This is the first report of Ostracoda associated with Crinoidea. None of the highly specialized appendages and/or carapace that are related to a commensal lifestyle were observed in O. crinophilum sp. nov. Therefore, the relationship between O. crinophilum sp. nov. and A. serrata must be transient rather than obligatory. However, O. crinophilum sp. nov. has a more developed hook-like distal claw on the antenna in comparison with four previously known Obesostoma species. The relatively well-developed distal claw of the antenna in O. crinophilum sp. nov. should indicate its intimate association with feather stars, though the feeding habit is still unknown.},
}
@article {pmid32972080,
year = {2020},
author = {Noda, T and Okude, G and Meng, XY and Koga, R and Moriyama, M and Fukatsu, T},
title = {Bacteriocytes and Blattabacterium Endosymbionts of the German Cockroach Blattella germanica, the Forest Cockroach Blattella nipponica, and Other Cockroach Species.},
journal = {Zoological science},
volume = {37},
number = {5},
pages = {399-410},
doi = {10.2108/zs200054},
pmid = {32972080},
issn = {0289-0003},
abstract = {Cockroaches are commonly found in human residences and notorious as hygienic and nuisance pests. Notably, however, no more than 30 cockroach species are regarded as pests, while the majority of 4,500 cockroaches in the world are living in forest environments with little relevance to human life. Why some cockroaches have exceptionally adapted to anthropic environments and established pest status is of interest. Here we investigated the German cockroach Blattella germanica, which is a cosmopolitan pest species, and the forest cockroach Blattella nipponica, which is a wild species closely related to B. germanica. In contrast to easy rearing of B. germanica, laboratory rearing of B. nipponica was challenging-several trials enabled us to keep the insects for up to three months. We particularly focused on the distribution patterns of specialized cells, bacteriocytes, for harboring endosymbiotic Blattabacterium, which has been suggested to contribute to host's nitrogen metabolism and recycling, during the postembryonic development of the insects. The bacteriocytes were consistently localized to visceral fat bodies filling the abdominal body cavity, where a number of single bacteriocytes were scattered among the adipocytes, throughout the developmental stages in both females and males. The distribution patterns of the bacteriocytes were quite similar between B. germanica and B. nipponica, and also among other diverse cockroach species, plausibly reflecting the highly conserved cockroach-Blattabacterium symbiotic association over evolutionary time. Our study lays a foundation to experimentally investigate the origin and the processes of urban pest evolution, on account of possible involvement of microbial associates.},
}
@article {pmid32972037,
year = {2020},
author = {Pandya, S and Ghayvat, H and Sur, A and Awais, M and Kotecha, K and Saxena, S and Jassal, N and Pingale, G},
title = {Pollution Weather Prediction System: Smart Outdoor Pollution Monitoring and Prediction for Healthy Breathing and Living.},
journal = {Sensors (Basel, Switzerland)},
volume = {20},
number = {18},
pages = {},
pmid = {32972037},
issn = {1424-8220},
abstract = {Air pollution has been a looming issue of the 21st century that has also significantly impacted the surrounding environment and societal health. Recently, previous studies have conducted extensive research on air pollution and air quality monitoring. Despite this, the fields of air pollution and air quality monitoring remain plagued with unsolved problems. In this study, the Pollution Weather Prediction System (PWP) is proposed to perform air pollution prediction for outdoor sites for various pollution parameters. In the presented research work, we introduced a PWP system configured with pollution-sensing units, such as SDS021, MQ07-CO, NO2-B43F, and Aeroqual Ozone (O3). These sensing units were utilized to collect and measure various pollutant levels, such as PM2.5, PM10, CO, NO2, and O3, for 90 days at Symbiosis International University, Pune, Maharashtra, India. The data collection was carried out between the duration of December 2019 to February 2020 during the winter. The investigation results validate the success of the presented PWP system. In the conducted experiments, linear regression and artificial neural network (ANN)-based AQI (air quality index) predictions were performed. Furthermore, the presented study also found that the customized linear regression methodology outperformed other machine-learning methods, such as linear, ridge, Lasso, Bayes, Huber, Lars, Lasso-lars, stochastic gradient descent (SGD), and ElasticNet regression methodologies, and the customized ANN regression methodology used in the conducted experiments. The overall AQI values of the air pollutants were calculated based on the summation of the AQI values of all the presented air pollutants. In the end, the web and mobile interfaces were developed to display air pollution prediction values of a variety of air pollutants.},
}
@article {pmid32971117,
year = {2020},
author = {Desai, D and Khanna, A and Pethe, P},
title = {PRC1 catalytic unit RING1B regulates early neural differentiation of human pluripotent stem cells.},
journal = {Experimental cell research},
volume = {396},
number = {1},
pages = {112294},
doi = {10.1016/j.yexcr.2020.112294},
pmid = {32971117},
issn = {1090-2422},
abstract = {BACKGROUND: Polycomb group (PcG) proteins are histone modifiers which control gene expression by assembling into large repressive complexes termed - Polycomb repressive complex (PRC); RING1B, core catalytic subunit of PRC1 that performs H2AK119 monoubiquitination leading to gene repression. The role of PRC1 complex during early neural specification in humans is unclear; we have tried to uncover the role of PRC1 in neuronal differentiation using human pluripotent stem cells as an in vitro model.
RESULTS: We differentiated both human embryonic stem cells (hESCs) and human induced pluripotent stem cells (hiPSCs) towards neural progenitor stage evident from the expression of NESTIN, TUJ1, NCAD, and PAX6. When we checked the total expression of RING1B and BMI1, we saw that they were significantly upregulated in differentiated neural progenitors compared to undifferentiated cells. Further, we used Chromatin Immunoprecipitation coupled with qPCR to determine the localization of RING1B, and the repressive histone modification H2AK119ub1 at the promoters of neuronal specific genes. We observed that RING1B localized to and catalyzed H2AK119ub1 modification at promoters of TUJ1, NCAM, and NESTIN during early differentiation and later RING1B was lost from its promoter leading their expression; while functional RING1B persisted significantly on mature neuronal genes such as IRX3, GSX2, SOX1, NEUROD1 and FOXG1 in neural progenitors.
CONCLUSION: The results of our study show that PRC1 catalytic component RING1B occupies neuronal gene promoters in human pluripotent stem cells and may prevent their precocious expression. However, when neuronal inductive signals are given, RING1B is not only removed from neuronal gene promoters, but the inhibitory H2AK119ub1 modification is also lost.},
}
@article {pmid32970846,
year = {2020},
author = {Roche, MD and Pearse, IS and Bialic-Murphy, L and Kivlin, SN and Sofaer, HR and Kalisz, S},
title = {Negative effects of an allelopathic invader on AM fungal plant species drive community-level responses.},
journal = {Ecology},
volume = {},
number = {},
pages = {e03201},
doi = {10.1002/ecy.3201},
pmid = {32970846},
issn = {1939-9170},
support = {//U.S. Geological Survey/ ; //National Science Foundation Graduate Research Internship Program/ ; //National Science Foundation Graduate Research Fellowship Program/ ; 0958676//National Science Foundation Long Term Research in Environmental Biology/ ; 144552//National Science Foundation Long Term Research in Environmental Biology/ ; 1457531//National Science Foundation Long Term Research in Environmental Biology/ ; },
abstract = {The mechanisms causing invasive species impact are rarely empirically tested, limiting our ability to understand and predict subsequent changes in invaded plant communities. Invader disruption of native mutualistic interactions is a mechanism expected to have negative effects on native plant species. Specifically, disruption of native plant-fungal mutualisms may provide non-mycorrhizal plant invaders an advantage over mycorrhizal native plants. Invasive Alliaria petiolata (garlic mustard) produces secondary chemicals toxic to soil microorganisms including mycorrhizal fungi, and is known to induce physiological stress and reduce population growth rates of native forest understory plant species. Here, we report on a 11-yr manipulative field experiment in replicated forest plots testing if the effects of removal of garlic mustard on the plant community support the mutualism disruption hypothesis within the entire understory herbaceous community. We compare community responses for two functional groups: the mycorrhizal vs. the non-mycorrhizal plant communities. Our results show that garlic mustard weeding alters the community composition, decreases community evenness, and increases the abundance of understory herbs that associate with mycorrhizal fungi. Conversely, garlic mustard has no significant effects on the non-mycorrhizal plant community. Consistent with the mutualism disruption hypothesis, our results demonstrate that allelochemical producing invaders modify the plant community by disproportionately impacting mycorrhizal plant species. We also demonstrate the importance of incorporating causal mechanisms of biological invasion to elucidate patterns and predict community-level responses.},
}
@article {pmid32970520,
year = {2020},
author = {Cao, Y and Jiang, G and Li, M and Fang, X and Zhu, D and Qiu, W and Zhu, J and Yu, D and Xu, Y and Zhong, Z and Zhu, J},
title = {Glutaredoxins Play an Important Role in the Redox Homeostasis and Symbiotic Capacity of Azorhizobium caulinodans ORS571.},
journal = {Molecular plant-microbe interactions : MPMI},
volume = {33},
number = {12},
pages = {1381-1393},
doi = {10.1094/MPMI-04-20-0098-R},
pmid = {32970520},
issn = {0894-0282},
abstract = {Glutaredoxin (GRX) plays an essential role in the control of the cellular redox state and related pathways in many organisms. There is limited information on GRXs from the model nitrogen (N2)-fixing bacterium Azorhizobium caulinodans. In the present work, we identified and performed functional analyses of monothiol and dithiol GRXs in A. caulinodans in the free-living state and during symbiosis with Sesbania rostrata. Our data show that monothiol GRXs may be very important for bacterial growth under normal conditions and in response to oxidative stress due to imbalance of the redox state in grx mutants of A. caulinodans. Functional redundancies were also observed within monothiol and dithiol GRXs in terms of different physiological functions. The changes in catalase activity and iron content in grx mutants were assumed to favor the maintenance of bacterial resistance against oxidants, nodulation, and N2 fixation efficiency in this bacterium. Furthermore, the monothiol GRX12 and dithiol GRX34 play a collective role in symbiotic associations between A. caulinodans and Sesbania rostrata. Our study provided systematic evidence that further investigations are required to understand the importance of glutaredoxins in A. caulinodans and other rhizobia.},
}
@article {pmid32969577,
year = {2020},
author = {Assis, APA and Thompson, JN and Santana, PC and Jordano, P and Bascompte, J and Guimarães, PR},
title = {Genetic correlations and ecological networks shape coevolving mutualisms.},
journal = {Ecology letters},
volume = {23},
number = {12},
pages = {1789-1799},
doi = {10.1111/ele.13605},
pmid = {32969577},
issn = {1461-0248},
support = {31003A_169671//Schweizerischer Nationalfonds zur Förderung der Wissenschaftlichen Forschung/ ; CGL2017-82847-P//Spanish Ministerio de Ciencia, Innovación y Universidades/ ; //Coordenação de Aperfeiçoamento de Pessoal de Nível Superior/ ; 140232/2018-4//Conselho Nacional de Desenvolvimento Científico e Tecnológico/ ; 2016/14277-2//Fundação de Amparo à Pesquisa do Estado de São Paulo/ ; 2018/14809-0//Fundação de Amparo à Pesquisa do Estado de São Paulo/ ; 140232//CNPq/ ; 2018-4//CNPq/ ; //National Science Foundation/ ; },
mesh = {*Biological Evolution ; Phenotype ; *Symbiosis ; },
abstract = {Ecological interactions shape the evolution of multiple species traits in populations. These traits are often linked to each other through genetic correlations, affecting how each trait evolves through selection imposed by interacting partners. Here, we integrate quantitative genetics, coevolutionary theory and network science to explore how trait correlations affect the coevolution of mutualistic species not only in pairs of species but also in species-rich networks across space. We show that genetic correlations may determine the pace of coevolutionary change, affect species abundances and fuel divergence among populations of the same species. However, this trait divergence promoted by genetic correlations is partially buffered by the nested structure of species-rich mutualisms. Our study, therefore, highlights how coevolution and its ecological consequences may result from conflicting processes at different levels of organisation, ranging from genes to communities.},
}
@article {pmid32968931,
year = {2020},
author = {Herrera-Rus, I and Pastor, JE and Juan, R},
title = {Fungal colonization associated with phenological stages of a photosynthetic terrestrial temperate orchid from the Southern Iberian Peninsula.},
journal = {Journal of plant research},
volume = {133},
number = {6},
pages = {807-825},
doi = {10.1007/s10265-020-01225-9},
pmid = {32968931},
issn = {1618-0860},
mesh = {*Basidiomycota/genetics ; DNA, Fungal ; *Mycorrhizae/genetics ; Orchidaceae/*microbiology/physiology ; Phylogeny ; Spain ; Symbiosis ; },
abstract = {Fungal endophytes, both mycorrhizal and non-mycorrhizal, are involved in the development of the life cycle of orchids, providing potential beneficial relationships. Here, we assess the succession of changes in the diversity of fungal symbionts associated with a terrestrial temperate orchid species, Anacamptis morio subsp. champagneuxii, over three phenological stages: developed leaves but no stem elongation, flowering, and fruiting. Fungi endophyte associated with roots were obtained by culture in sterile conditions. A total of 18 morphotypes-one Mortierellomycota, two Basidiomycota and 15 Ascomycota-were differentiated, and were also characterized using PCR and DNA sequencing techniques. Only three of the 18 OTUs are shared among the three phenological stages examined: Westerdykella sp., a member of Ceratobasidiaceae, and Fusarium oxysporum, representing a relative abundance of between 28% (fruiting) to 41% (flowering). Our research confirmed that fungal symbionts varied among the different phenological stages examined, the peak of endophyte diversity appearing in the flowering stage. The availability of a diverse mycobiota seems to be important for the survival of orchid plants because it may cover particular physiological needs, and knowledge concerning this mycobiota is of special relevance in the establishment of reliable conservation programmes.},
}
@article {pmid32968213,
year = {2021},
author = {Nelson, C and Giraldo-Silva, A and Garcia-Pichel, F},
title = {A symbiotic nutrient exchange within the cyanosphere microbiome of the biocrust cyanobacterium, Microcoleus vaginatus.},
journal = {The ISME journal},
volume = {15},
number = {1},
pages = {282-292},
pmid = {32968213},
issn = {1751-7370},
abstract = {Microcoleus vaginatus plays a prominent role as both primary producer and pioneer in biocrust communities from dryland soils. And yet, it cannot fix dinitrogen, essential in often nitrogen-limited drylands. But a diazotroph-rich "cyanosphere" has been described in M. vaginatus, hinting that there exists a C for N exchange between the photoautotroph and heterotrophic diazotrophs. We provide evidence for this by establishing such a symbiosis in culture and by showing that it is selective and dependent on nitrogen availability. In natural populations, provision of nitrogen resulted in loss of diazotrophs from the cyanosphere of M. vaginatus compared to controls, but provision of phosphorus did not. Co-culturing of pedigreed cyanosphere diazotroph isolates with axenic M. vaginatus resulted in copious growth in C and N-free medium, but co-culture with non-cyanosphere diazotrophs or other heterotrophs did not. Unexpectedly, bundle formation in M. vaginatus, diacritical to the genus but not seen in axenic culture, was restored in vitro by imposed nitrogen limitation or, even more strongly, by co-culture with diazotrophic partners, implicating this trait in the symbiosis. Our findings provide direct evidence for a symbiotic relationship between M. vaginatus and its cyanosphere and help explain how it can be a global pioneer in spite of its genetic shortcomings.},
}
@article {pmid32966595,
year = {2021},
author = {Ho-Plágaro, T and Morcillo, RJL and Tamayo-Navarrete, MI and Huertas, R and Molinero-Rosales, N and López-Ráez, JA and Macho, AP and García-Garrido, JM},
title = {DLK2 regulates arbuscule hyphal branching during arbuscular mycorrhizal symbiosis.},
journal = {The New phytologist},
volume = {229},
number = {1},
pages = {548-562},
doi = {10.1111/nph.16938},
pmid = {32966595},
issn = {1469-8137},
support = {//Fondos Europeos de Desarrollo Regional (FEDER)/ ; AGL2014-52298-P//Ministerio de Economía, industria y Competitividad/ ; AGL2017-83871-P//Ministerio de Economía, industria y Competitividad/ ; //Comisión Interministerial de Ciencia y Tecnología/ ; //Chinese Academy of Sciences/ ; //Chinese 1000 Talents program/ ; },
abstract = {D14 and KAI2 receptors enable plants to distinguish between strigolactones (SLs) and karrikins (KARs), respectively, in order to trigger appropriate environmental and developmental responses. Both receptors are related to the regulation of arbuscular mycorrhiza (AM) formation and are members of the RsbQ-like family of α,β-hydrolases. DLK2 proteins, whose function remains unknown, constitute a third clade from the RsbQ-like protein family. We investigated whether the tomato SlDLK2 is a new regulatory component in the AM symbiosis. Genetic approaches were conducted to analyze SlDLK2 expression and to understand SlDLK2 function in AM symbiosis. We show that SlDLK2 expression in roots is AM-dependent and is associated with cells containing arbuscules. SlDLK2 ectopic expression arrests arbuscule branching and downregulates AM-responsive genes, even in the absence of symbiosis; while the opposite effect was observed upon SlDLK2 silencing. Moreover, SlDLK2 overexpression in Medicago truncatula roots showed the same altered phenotype observed in tomato roots. Interestingly, SlDLK2 interacts with DELLA, a protein that regulates arbuscule formation/degradation in AM roots. We propose that SlDLK2 is a new component of the complex plant-mediated mechanism regulating the life cycle of arbuscules in AM symbiosis.},
}
@article {pmid32963432,
year = {2020},
author = {Shukla, U and Chavali, S and Mukta, P and Mapari, A and Vyas, A},
title = {Initial Experience of Critically Ill Patients with COVID-19 in Western India: A Case Series.},
journal = {Indian journal of critical care medicine : peer-reviewed, official publication of Indian Society of Critical Care Medicine},
volume = {24},
number = {7},
pages = {509-513},
pmid = {32963432},
issn = {0972-5229},
abstract = {Background: The novel coronavirus, named SARS-CoV-2, was first described in December 2019 as a cluster of pneumonia cases in Wuhan, China. It has since been declared a pandemic, with substantial mortality.
Materials and methods: In our case series, we describe the clinical presentation, characteristics, and outcomes of our initial experience of managing 24 critically ill COVID-19 patients at a designated COVID-19 ICU in Western India.
Results: Median age of the patients was 54 years, and 58% were males. All patients presented with moderate to severe acute respiratory distress syndrome (ARDS); however, only 37.5% failed trials of awake proning and required mechanical ventilation. Patients who received mechanical ventilation typically matched the H-phenotype of COVID-19 pneumonia, and 55.5% of these patients were successfully extubated.
Conclusion: The most common reason for ICU admission in our series of 24 patients with severe COVID-19 was hypoxemic respiratory failure, which responded well to conservative measures such as awake proning and oxygen supplementation. Mortality in our case series was 16.7%.
How to cite this article: Shukla U, Chavali S, Mukta P, Mapari A, Vyas A. Initial Experience of Critically Ill Patients with COVID-19 in Western India: A Case Series. Indian J Crit Care Med 2020;24(7):509-513.},
}
@article {pmid32961808,
year = {2020},
author = {Salcedo-Porras, N and Umaña-Diaz, C and Bitencourt, ROB and Lowenberger, C},
title = {The Role of Bacterial Symbionts in Triatomines: An Evolutionary Perspective.},
journal = {Microorganisms},
volume = {8},
number = {9},
pages = {},
pmid = {32961808},
issn = {2076-2607},
support = {Discovery Grant #261940//Natural Sciences and Engineering Research Council of Canada/ ; President's Research Grant and a graduate Fellowship//Simon Fraser University/ ; Emerging Leaders of the Americas Fellowship//Government of Canada/ ; },
abstract = {Insects have established mutualistic symbiotic interactions with microorganisms that are beneficial to both host and symbiont. Many insects have exploited these symbioses to diversify and expand their ecological ranges. In the Hemiptera (i.e., aphids, cicadas, and true bugs), symbioses have established and evolved with obligatory essential microorganisms (primary symbionts) and with facultative beneficial symbionts (secondary symbionts). Primary symbionts are usually intracellular microorganisms found in insects with specialized diets such as obligate hematophagy or phytophagy. Most Heteroptera (true bugs), however, have gastrointestinal (GI) tract extracellular symbionts with functions analogous to primary endosymbionts. The triatomines, are vectors of the human parasite, Trypanosoma cruzi. A description of their small GI tract microbiota richness was based on a few culturable microorganisms first described almost a century ago. A growing literature describes more complex interactions between triatomines and bacteria with properties characteristic of both primary and secondary symbionts. In this review, we provide an evolutionary perspective of beneficial symbioses in the Hemiptera, illustrating the context that may drive the evolution of symbioses in triatomines. We highlight the diversity of the triatomine microbiota, bacterial taxa with potential to be beneficial symbionts, the unique characteristics of triatomine-bacteria symbioses, and the interactions among trypanosomes, microbiota, and triatomines.},
}
@article {pmid32961677,
year = {2020},
author = {Wilker, J and Humphries, S and Rosas-Sotomayor, JC and Cerna, MG and Torkamaneh, D and Edwards, M and Navabi, A and Pauls, KP},
title = {Genetic Diversity, Nitrogen Fixation, and Water Use Efficiency in a Panel of Honduran Common Bean (Phaseolus vulgaris L.) Landraces and Modern Genotypes.},
journal = {Plants (Basel, Switzerland)},
volume = {9},
number = {9},
pages = {},
pmid = {32961677},
issn = {2223-7747},
abstract = {Common bean (Phaseolus vulgaris L.) provides critical nutrition and a livelihood for millions of smallholder farmers worldwide. Beans engage in symbiotic nitrogen fixation (SNF) with Rhizobia. Honduran hillside farmers farm marginal land and utilize few production inputs; therefore, bean varieties with high SNF capacity and environmental resiliency would be of benefit to them. We explored the diversity for SNF, agronomic traits, and water use efficiency (WUE) among 70 Honduran landrace, participatory bred (PPB), and conventionally bred bean varieties (HON panel) and 6 North American check varieties in 3 low-N field trials in Ontario, Canada and Honduras. Genetic diversity was measured with a 6K single nucleotide polymorphism (SNP) array, and phenotyping for agronomic, SNF, and WUE traits was carried out. STRUCTURE analysis revealed two subpopulations with admixture between the subpopulations. Nucleotide diversity was greater in the landraces than the PPB varieties across the genome, and multiple genomic regions were identified where population genetic differentiation between the landraces and PPB varieties was evident. Significant differences were found between varieties and breeding categories for agronomic traits, SNF, and WUE. Landraces had above average SNF capacity, conventional varieties showed higher yields, and PPB varieties performed well for WUE. Varieties with the best SNF capacity could be used in further participatory breeding efforts.},
}
@article {pmid32961487,
year = {2020},
author = {Sun, YH and Gu, CX and Li, GZ and Han, AH and Hao, L},
title = {Arbuscular mycorrhizal fungus-mediated amelioration of NO2-induced phytotoxicity in tomato.},
journal = {Ecotoxicology and environmental safety},
volume = {205},
number = {},
pages = {111350},
doi = {10.1016/j.ecoenv.2020.111350},
pmid = {32961487},
issn = {1090-2414},
mesh = {Antioxidants/metabolism ; Chlorophyll/metabolism ; Hydrogen Peroxide/metabolism ; Lycopersicon esculentum/metabolism/microbiology/*physiology ; Mycorrhizae/metabolism/*physiology ; Nitrogen Dioxide/*toxicity ; Oxidation-Reduction ; Photosynthesis/physiology ; Plant Development ; Plant Leaves/metabolism ; },
abstract = {Atmospheric nitrogen dioxide (NO2) negatively affects plant (crop) growth and development, as well the yield and quality in some regions or environments. Arbuscular mycorrhizal fungus (AMF)-mediated amelioration of NO2-induced plant damage has been reported, but the underlying mechanisms remained unclear. This study explored the beneficial effect of AMF symbiosis on tomato plant responses to NO2 at physiology, biochemistry, and gene expression, with an emphasis on nitrate metabolism, antioxidative defense, and photosynthetic performance. Pot-grown plants were used in the experiments, which were performed in laboratory from February to November 2019. NO2 fumigation with a dose of 10 ± 1 ppm was carried out after 50 d of plant growth, and data were collected following 8 h of fumigation. NO2 fumigation (+NO2) and AMF inoculation (+AMF), alone and especially in combination (NO2 + AMF), increased the gene expression of nitrate- and nitrite reductase, and their enzymatic activity in leaves, such as by 61%, 27%, and 126% for the activity of nitrate reductase, and by 95%, 37%, and 188% for nitrite reductase, respectively, in +NO2, +AMF, and AMF + NO2 plants relative the control (-NO2, -AMF) levels. Following NO2 exposure, +AMF leaves displayed stronger activities of superoxide dismutase, peroxidase and catalase, and higher content of glutathione and ratio of its reduced form to oxidized form, as compared with -AMF ones. Correspondingly, lesser oxidative damage was detected in +AMF than in -AMF plants, as indicated by the contents of H2O2 and malondialdehyde, electrolyte leakage, also by in situ visualization for the formation of H2O2, superoxide anion, and dead cells. The increased antioxidative capacity in +AMF plants was correlated with enhanced expression of antioxidation-related genes. Exposure to NO2 substantially impaired photosynthetic processes in both + AMF and -AMF plants, but an obvious mitigation was observed in the former than in the latter. For example, the total chlorophyll, net photosynthetic rate, stomatal conductance, and ribulose-1,5-bisphosphate carboxylase activity were 18%, 27%, 26%, and 40% higher, respectively, in +AMF than in -AMF plants under NO2 stress. The differential photosynthetic performance was also revealed by chlorophyll fluorescence imaging. We analyzed the expression patterns of some genes related to photosynthesis and carbon metabolisms, and found that all of them exclusively presented a higher expression level in +AMF plants relative to -AMF ones under NO2 stress. Taken together, this study provided evidence that AMF symbiosis played a positively regulatory role in host plant responses to NO2, probably by increasing leaf nitrate metabolism and antioxidative defense, and maintaining the photosynthetic efficiency to some extent, wherein the transcription regulation might be a main target.},
}
@article {pmid32957892,
year = {2020},
author = {Pendse, S and Kale, V and Vaidya, A},
title = {Extracellular Vesicles Isolated from Mesenchymal Stromal Cells Primed with Hypoxia: Novel strategy in Regenerative Medicine.},
journal = {Current stem cell research & therapy},
volume = {},
number = {},
pages = {},
doi = {10.2174/1574888X15999200918110638},
pmid = {32957892},
issn = {2212-3946},
abstract = {Mesenchymal stromal cells (MSCs) regulate other cell types through a strong paracrine component called the secretome, comprising of several bioactive entities. The composition of the MSCs' secretome is dependent upon the microenvironment in which they thrive, and hence, it could be altered by pre-conditioning the MSCs during in vitro culture. The primary aim of this review is to discuss various strategies that are being used for pre-conditioning of MSCs, also known as "priming of MSCs", in the context of improving their therapeutic potential. Several studies have underscored the importance of extracellular vesicles (EVs) derived from primed MSCs in improving their efficacy in the treatment of various diseases. We have previously shown that co-culturing hematopoietic stem cells (HSCs) with hypoxiaprimed MSCs improves their engraftment potential. Now the question we pose is would priming of MSCs with hypoxiafavorably alter theirsecretome and would this altered secretome work as effectively as the cell to cell contact did? Here we review the current strategies of using the secretome, specifically the EVs (microvesicles and exosomes), collected from the primed MSCs with the intention of expanding HSCs ex vivo. We speculate that an effective priming of MSCs in vitrocould modulate the molecular profile of their secretome, which could eventually be used as a cell-free biologic in clinical settings.},
}
@article {pmid32956757,
year = {2021},
author = {Lin, YE and Wang, HL and Lu, KH and Huang, YJ and Panyod, S and Liu, WT and Yang, SH and Chen, MH and Lu, YS and Sheen, LY},
title = {Water extract of Armillaria mellea (Vahl) P. Kumm. Alleviates the depression-like behaviors in acute- and chronic mild stress-induced rodent models via anti-inflammatory action.},
journal = {Journal of ethnopharmacology},
volume = {265},
number = {},
pages = {113395},
doi = {10.1016/j.jep.2020.113395},
pmid = {32956757},
issn = {1872-7573},
abstract = {ETHNOPHARMACOLOGY RELEVANCE: Armillaria mellea (Vahl) P. Kumm. (AM) is an edible mushroom that has been reported as treatment for several neurological disorders, such as dizziness and epilepsy in Asia. Importantly, AM shares a symbiotic relationship with Gastrodia elata Blume (GE), a medicinal herb with antidepressant-like properties. Researchers believe that AM may possess pharmacological properties similar to GE due to their symbiosis, however, few studies have investigated the pharmacological effect of AM.
AIM OF THE STUDY: The aim of this study was to explore the potential of AM as an antidepressant in forced-swimming test (FST) and unpredictable chronic mild stress (UCMS) rodent models and investigate its possible underlying mechanism.
MATERIALS AND METHODS: Rats were orally administrated with 250, 500, and 1000 mg/kg body weight (bw) water extract of AM (WAM) for 28 and 35 consecutive days prior to the FST and UCMS protocols, respectively. The cerebral serotonin (5-HT) and the metabolites in the frontal cortex of rats were measured. The brain was dissected and the blood was collected to investigate the levels of inflammatory-related signaling pathway.
RESULTS: All doses of WAM reduced the immobility time in the FST without disturbing autonomic locomotion. All doses of WAM prevented stress-induced abnormal behaviors in the UCMS model, including decreased sucrose preference and hypoactivity. 500 and 1000 mg/kg bw WAM attenuated the stress-induced increases in IL-1β and TNF-α in the serum and cerebrum. 1000 mg/kg bw WAM alleviated brain inflammation by reducing the protein expression of ionized calcium binding adaptor molecule 1.
CONCLUSION: WAM exhibited acute and chronic antidepressant-like effects, and may result from the anti-inflammatory actions. Therefore, the development of AM as a dietary therapy or adjuvant for depression treatment should be considered.},
}
@article {pmid32956755,
year = {2020},
author = {Štolhoferová, I and Holubová, K and Vobrubová, B and Kaftanová, B and Frynta, D},
title = {On the ground and in the heights: Does exploratory activity differ in commensal and non-commensal spiny mice?.},
journal = {Behavioural processes},
volume = {180},
number = {},
pages = {104252},
doi = {10.1016/j.beproc.2020.104252},
pmid = {32956755},
issn = {1872-8308},
mesh = {Animals ; Ecosystem ; Mice ; Mice, Inbred Strains ; *Murinae ; *Symbiosis ; },
abstract = {Human settlements represent a specific environment where commensal animals are exposed to different selective pressures than their wild-living conspecifics. Despite the importance of commensal rodents for human health and economy, little is known about how a transition to a commensal way of life changes the behaviour of the animals. We tested twelve populations of spiny mice (Acomys spp.) in two open field-type tests - a vertical test and a hole board test. In the vertical test, a wire mesh for climbing was offered to spiny mice. We used a multipopulation approach using two commensal and ten non-commensal spiny mouse populations to account for inter-population variability. We aimed to investigate whether there are differences in behaviour of commensal and non-commensal populations with special regard to their exploratory activity both on the ground and on the wire mesh. We found that all non-commensal populations behaved similarly despite their long separate evolutionary histories. Contrary, the commensal populations were less exploratory on the ground in both tests. We concluded that this change was associated with their transition to commensalism. This shows that selective pressures of the commensal environment are able to induce noticeable changes in behaviour after a very short evolutionary time.},
}
@article {pmid32956455,
year = {2020},
author = {Ip, JC and Xu, T and Sun, J and Li, R and Chen, C and Lan, Y and Han, Z and Zhang, H and Wei, J and Wang, H and Tao, J and Cai, Z and Qian, PY and Qiu, JW},
title = {Host-Endosymbiont Genome Integration in a Deep-Sea Chemosymbiotic Clam.},
journal = {Molecular biology and evolution},
volume = {},
number = {},
pages = {},
doi = {10.1093/molbev/msaa241},
pmid = {32956455},
issn = {1537-1719},
abstract = {Endosymbiosis with chemosynthetic bacteria has enabled many deep-sea invertebrates to thrive at hydrothermal vents and cold seeps, but most previous studies on this mutualism have focused on the bacteria only. Vesicomyid clams dominate global deep-sea chemosynthesis-based ecosystems. They differ from most deep-sea symbiotic animals in passing their symbionts from parent to offspring, enabling intricate co-evolution between the host and the symbiont. Here, we sequenced the genomes of the clam Archivesica marissinica (Bivalvia: Vesicomyidae) and its bacterial symbiont to understand the genomic/metabolic integration behind this symbiosis. At 1.52 gigabases, the clam genome encodes 28 genes horizontally transferred from bacteria, a large number of pseudogenes and transposable elements whose massive expansion corresponded to the timing of the rise and subsequent divergence of symbiont-bearing vesicomyids. The genome exhibits gene family expansion in cellular processes that likely facilitate chemoautotrophy, including gas delivery to support energy and carbon production, metabolite exchange with the symbiont, and regulation of the bacteriocyte population. Contraction in cellulase genes is likely adaptive to the shift from phytoplankton-derived to bacteria-based food. It also shows contraction in bacterial recognition gene familie, indicative of suppressed immune response to the endosymbiont. The gammaproteobacterium endosymbiont has a reduced genome of 1.03 megabases but retains complete pathways for sulfur oxidation, carbon fixation, and biosynthesis of 20 common amino acids, indicating the host's high dependence on the symbiont for nutrition. Overall, the host-symbiont genomes show not only tight metabolic complementarity, but also distinct signatures of co-evolution allowing the vesicomyids to thrive in chemosynthesis-based ecosystems.},
}
@article {pmid32956411,
year = {2020},
author = {Spahr, E and Kasson, MT and Kijimoto, T},
title = {Micro-computed tomography permits enhanced visualization of mycangia across development and between sexes in Euwallacea ambrosia beetles.},
journal = {PloS one},
volume = {15},
number = {9},
pages = {e0236653},
pmid = {32956411},
issn = {1932-6203},
mesh = {Animals ; Coleoptera/anatomy & histology/*growth & development/*ultrastructure ; Female ; Larva/anatomy & histology/growth & development/ultrastructure ; Male ; Pupa/anatomy & histology/growth & development/ultrastructure ; Sex Characteristics ; X-Ray Microtomography ; },
abstract = {Symbiosis can facilitate the development of specialized organs in the host body to maintain relationships with beneficial microorganisms. To understand the developmental and genetic mechanisms by which such organs develop, it is critical to first investigate the morphology and developmental timing of these structures during the onset of host development. We utilized micro-computed tomography (μCT) to describe the morphology and development of mycangia, a specialized organ, in the Asian ambrosia beetle species Euwallacea validus which maintains a mutualistic relationship with the Ascomycete fungus, Fusarium oligoseptatum. We scanned animals in larval, pupal and adult life stages and identified that mycangia develop during the late pupal stage. Here we reconcile preliminary evidence and provide additional morphological data for a second paired set of structures, including the superior, medial mycangia and an inferior, lateral pair of pouch-like structures, in both late-stage pupae and adult female beetles. Furthermore, we report the possible development of rudimentary, or partially developed pairs of medial mycangia in adult male beetles which has never been reported for any male Xyleborini. Our results illustrate the validity of μCT in observing soft tissues and the complex nature of mycangia morphology and development.},
}
@article {pmid32953252,
year = {2020},
author = {Kang, Z and Zou, J and Huang, Y and Zhang, X and Ye, L and Zhang, B and Zhang, X and Li, X},
title = {Tuber melanosporum shapes nirS-type denitrifying and ammonia-oxidizing bacterial communities in Carya illinoinensis ectomycorrhizosphere soils.},
journal = {PeerJ},
volume = {8},
number = {},
pages = {e9457},
pmid = {32953252},
issn = {2167-8359},
abstract = {Background: NirS-type denitrifying bacteria and ammonia-oxidizing bacteria (AOB) play a key role in the soil nitrogen cycle, which may affect the growth and development of underground truffles. We aimed to investigate nirS-type denitrifying bacterial and AOB community structures in the rhizosphere soils of Carya illinoinensis seedlings inoculated with the black truffle (Tuber melanosporum) during the early symbiotic stage.
Methods: The C. illinoinensis seedlings inoculated with or without T. melanosporum were cultivated in a greenhouse for six months. Next-generation sequencing (NGS) technology was used to analyze nirS-type denitrifying bacterial and AOB community structures in the rhizosphere soils of these seedlings. Additionally, the soil properties were determined.
Results: The results indicated that the abundance and diversity of AOB were significantly reduced due to the inoculation of T. melanosporum, while these of nirS-type denitrifying bacteria increased significantly. Proteobacteria were the dominant bacterial groups, and Rhodanobacter, Pseudomonas, Nitrosospira and Nitrosomonas were the dominant classified bacterial genera in all the soil samples. Pseudomonas was the most abundant classified nirS-type denitrifying bacterial genus in ectomycorrhizosphere soils whose relative abundance could significantly increase after T. melanosporum inoculation. A large number of unclassified nirS-type denitrifying bacteria and AOB were observed. Moreover, T. melanosporum inoculation had little effect on the pH, total nitrogen (TN), nitrate-nitrogen (NO 3 - -N) and ammonium-nitrogen (NH 4 + -N) contents in ectomycorrhizosphere soils. Overall, our results showed that nirS-type denitrifying bacterial and AOB communities in C. illinoinensis rhizosphere soils were significantly affected by T. melanosporum on the initial stage of ectomycorrhizal symbiosis, without obvious variation of soil N contents.},
}
@article {pmid32953071,
year = {2020},
author = {Griffin, LH and Reed, LK},
title = {Effect of gut microbiota on α-amanitin tolerance in Drosophila tripunctata.},
journal = {Ecology and evolution},
volume = {10},
number = {17},
pages = {9419-9427},
pmid = {32953071},
issn = {2045-7758},
abstract = {The bacterial gut microbiota of many animals is known to be important for many physiological functions including detoxification. The selective pressures imposed on insects by exposure to toxins may also be selective pressures on their symbiotic bacteria, who thus may contribute to the mechanism of toxin tolerance for the insect. Amatoxins are a class of cyclopeptide mushroom toxins that primarily act by binding to RNA polymerase II and inhibiting transcription. Several species of mycophagous Drosophila are tolerant to amatoxins found in mushrooms of the genus Amanita, despite these toxins being lethal to most other known eukaryotes. These species can tolerate amatoxins in natural concentrations to utilize toxic mushrooms as larval hosts, but the mechanism by which these species are tolerant remains unknown. Previous data have shown that a local population of D. tripunctata exhibits significant genetic variation in toxin tolerance. This study assesses the potential role of the microbiome in α-amanitin tolerance in six wild-derived strains of Drosophila tripunctata. Normal and antibiotic-treated samples of six strains were reared on diets with and without α-amanitin, and then scored for survival from the larval stage to adulthood and for development time to pupation. Our results show that a substantial reduction in bacterial load does not influence toxin tolerance in this system, while confirming genotype and toxin-specific effects on survival are independent of the microbiome composition. Thus, we conclude that this adaptation to exploit toxic mushrooms as a host is likely intrinsic to the fly's genome and not a property of their microbiome.},
}
@article {pmid32947777,
year = {2020},
author = {Cantamessa, S and Massa, N and Gamalero, E and Berta, G},
title = {Phytoremediation of a Highly Arsenic Polluted Site, Using Pteris vittata L. and Arbuscular Mycorrhizal Fungi.},
journal = {Plants (Basel, Switzerland)},
volume = {9},
number = {9},
pages = {},
pmid = {32947777},
issn = {2223-7747},
support = {2007PKFAAT - Mechanisms of response to arsenic and cadmium in model plants//Italian Ministry for Education and Scientific Research, PRIN 2007/ ; },
abstract = {Phytoremediation is a promising green technique for the restoration of a polluted environment, but there is often a gap between lab and field experiments. The fern, Pteris vittata L., can tolerate a high soil arsenic concentration and rapidly accumulate the metalloid in its fronds. Arbuscular mycorrhizal fungi (AMF) are mutualistic fungi that form a symbiosis with most land plants' roots, improve their growth, and induce stress tolerance. This paper reports the results obtained using P. vittata inoculated with AMF, to extract Arsenic (As) from an industrial site highly contaminated also by other pollutants. Two experiments have been performed. In the first one, AMF colonized ferns were grown for two years under controlled conditions in soil coming from the metallurgic site. Positive effects on plant health and As phytoextraction and accumulation were detected. Then, considering these results, we performed a three year in situ experiment in the industrial site, to assess the remediation of As at two different depths. Our results show that the colonization of P. vittata with AMF improved the remediation process of As with a significant impact on the depth 0-0.2 m.},
}
@article {pmid32947656,
year = {2020},
author = {Kullu, B and Patra, DK and Acharya, S and Pradhan, C and Patra, HK},
title = {AM fungi mediated bioaccumulation of hexavalent chromium in Brachiaria mutica-a mycorrhizal phytoremediation approach.},
journal = {Chemosphere},
volume = {258},
number = {},
pages = {127337},
doi = {10.1016/j.chemosphere.2020.127337},
pmid = {32947656},
issn = {1879-1298},
mesh = {Antioxidants/metabolism ; Bioaccumulation ; *Biodegradation, Environmental ; Brachiaria/*metabolism ; Chlorophyll/metabolism ; Chromium/analysis/*metabolism ; Glomeromycota/metabolism ; Mycorrhizae/metabolism ; Photosynthesis ; Plants/metabolism ; Poaceae/metabolism ; Soil ; Soil Pollutants/analysis/*metabolism ; Symbiosis ; },
abstract = {The experiment was designed to evaluate the roles of Rhizophagus irregularis on chlorophyll fluorescence and chromium bioaccumulation in a grass species (Brachiaria mutica) by supplementing Cr+6 at different concentrations. Arbuscular Mycorrhizal Fungi (AMF) association facilitated lessening of chromium level in contaminated soil and enhanced chromium bioavailability in Brachiaria mutica. The mycorrhizal inoculated increased the chlorophyll (0.925 mg/g), carotenoid (0.127 mg/g), protein (2.883 mg/g), proline (0.889 mg/g) contents and activities of antioxidant enzymes like catalase, ascorbate peroxidase and glutathione peroxidase. The mycorrhizal inoculated plants also showed enhanced overall photosynthetic performance (PIϕ = 2.473) and enhanced PS-II to PS-I electron transport as evident from yield parameter (0.712) and TR0/RC (2.419) for 60 mg/kg Cr+6 treatment. The observations suggest that AMF association could defend the plants from chromium stress by elevating the number of antioxidants in plants. Rhizophagus irregularis was found to maintain a successful symbiotic relationship with Brachiaria mutica in chromium contaminated soil. The observations recommended that Rhizophagus irregularis in association with Brachiaria mutica would be an innovative approach for decontamination of Cr+6.},
}
@article {pmid32944158,
year = {2020},
author = {Kin, LX and Butler, CA and Slakeski, N and Hoffmann, B and Dashper, SG and Reynolds, EC},
title = {Metabolic cooperativity between Porphyromonas gingivalis and Treponema denticola.},
journal = {Journal of oral microbiology},
volume = {12},
number = {1},
pages = {1808750},
pmid = {32944158},
issn = {2000-2297},
abstract = {Background: Porphyromonas gingivalis and Treponema denticola are proteolytic periodontopathogens that co-localize in polymicrobial subgingival plaque biofilms, display in vitro growth symbiosis and synergistic virulence in animal models of disease. These symbioses are underpinned by a range of metabolic interactions including cooperative hydrolysis of glycine-containing peptides to produce free glycine, which T. denticola uses as a major energy and carbon source.
Objective: To characterize the P. gingivalis gene products essential for these interactions. Methods: The P. gingivalis transcriptome exposed to cell-free T. denticola conditioned medium was determined using RNA-seq. P. gingivalis proteases potentially involved in hydrolysis of glycine-containing peptides were identified using a bioinformatics approach.
Results: One hundred and thirty-twogenes displayed differential expression, with the pattern of gene expression consistent with succinate cross-feeding from T. denticola to P. gingivalis and metabolic shifts in the P. gingivalis folate-mediated one carbon superpathway. Interestingly, no P. gingivalis proteases were significantly up-regulated. Three P. gingivalis proteases were identified as candidates and inactivated to determine their role in the release of free glycine. P. gingivalis PG0753 and PG1788 but not PG1605 are involved in the hydrolysis of glycine-containing peptides, making free glycine available for T. denticola utilization.
Conclusion: Collectively these metabolic interactions help to partition resources and engage synergistic interactions between these two species.},
}
@article {pmid32938948,
year = {2020},
author = {Denison, ER and Rhodes, RG and McLellan, WA and Pabst, DA and Erwin, PM},
title = {Host phylogeny and life history stage shape the gut microbiome in dwarf (Kogia sima) and pygmy (Kogia breviceps) sperm whales.},
journal = {Scientific reports},
volume = {10},
number = {1},
pages = {15162},
pmid = {32938948},
issn = {2045-2322},
mesh = {Animals ; Biodiversity ; *Gastrointestinal Microbiome/genetics ; Host Microbial Interactions ; Life Cycle Stages ; Phylogeny ; RNA, Ribosomal, 16S/genetics ; Species Specificity ; Symbiosis ; Whales/classification/growth & development/*microbiology ; },
abstract = {Gut microbiomes perform crucial roles in host health and development, but few studies have explored cetacean microbiomes especially deep divers. We characterized the gut microbiomes of stranded dwarf (Kogia sima) and pygmy (K. breviceps) sperm whales to examine the effects of phylogeny and life stage on microbiome composition and diversity. 16S rRNA gene sequence analysis revealed diverse gut communities (averaging 674 OTUs) dominated by a few symbiont taxa (25 OTUs accounted for 64% of total relative abundance). Both phylogeny and life stage shaped community composition and diversity, with species-specific microbiome differences present early in life. Further analysis showed evidence of microbiome convergence with host maturity, albeit through different processes: symbiont 'accumulation' in K. sima and 'winnowing' in K. breviceps, indicating different methods of community assembly during host development. Furthermore, culture-based analyses yielded 116 pure cultures matching 25 OTUs, including one isolate positive for chitin utilization. Our findings indicate that kogiid gut microbiomes are highly diverse and species-specific, undergo significant shifts with host development, and can be cultivated on specialized media under anaerobic conditions. These results enhance our understanding of the kogiid gut microbiome and may provide useful information for symbiont assessment in host health.},
}
@article {pmid32937935,
year = {2020},
author = {Vilcinskas, A and Schwabe, M and Brinkrolf, K and Plarre, R and Wielsch, N and Vogel, H},
title = {Larvae of the Clothing Moth Tineola bisselliella Maintain Gut Bacteria that Secrete Enzyme Cocktails to Facilitate the Digestion of Keratin.},
journal = {Microorganisms},
volume = {8},
number = {9},
pages = {},
pmid = {32937935},
issn = {2076-2607},
support = {AIM-Biotech//Max-Planck-Gesellschaft/ ; AIM-Biotech//Fraunhofer-Gesellschaft/ ; LOEWE//Hessen Ministry of Science and Art/ ; },
abstract = {The evolutionary success of insects is promoted by their association with beneficial microbes that enable the utilization of unusual diets. The synanthropic clothing moth Tineola bisselliella provides an intriguing example of this phenomenon. The caterpillars of this species have adapted to feed on keratin-rich diets such as feathers and wool, which cannot be digested by most other animals and are resistant to common digestive enzymes. Inspired by the hypothesis that this ability may be conferred by symbiotic microbes, we utilized a simple assay to detect keratinase activity and a method to screen gut bacteria for candidate enzymes, which were isolated from feather-fed larvae. The isolation of DNA from keratin-degrading bacterial strains followed by de novo genome sequencing resulted in the identification of a novel bacterial strain related to Bacillus sp. FDAARGOS_235. Genome annotation identified 20 genes with keratinase domains. Proteomic analysis of the culture supernatant from this gut bacterium grown in non-nutrient buffer supplemented with feathers revealed several candidate enzymes potentially responsible for keratin degradation, including a thiol-disulfide oxidoreductase and multiple proteases. Our results suggest that the unusual diet of T. bisselliella larvae promotes their association with keratinolytic microorganisms and that the ability of larvae to feed on keratin can at least partially be attributed to bacteria that produce a cocktail of keratin-degrading enzymes.},
}
@article {pmid32936397,
year = {2020},
author = {He, C and Liu, Y and Ye, S and Yin, S and Gu, J},
title = {Changes of intestinal microflora of breast cancer in premenopausal women.},
journal = {European journal of clinical microbiology & infectious diseases : official publication of the European Society of Clinical Microbiology},
volume = {},
number = {},
pages = {},
doi = {10.1007/s10096-020-04036-x},
pmid = {32936397},
issn = {1435-4373},
support = {KJ2019A0427//Anhui university natural science research project/ ; HWK2016ZC007//Applied Medical Research Project of Hefei Municipal Health Commission/ ; WK2019F42//Young Research Fund of Wannan Medical College/ ; },
abstract = {Breast cancer is one of the most common malignant tumors in women. More than half of breast cancer patients are not menopausal at the time of diagnosis. The occurrence and development of premenopausal breast cancer are affected by many factors. Intestinal flora, especially SCFA-producing bacteria, participates in the development of various tumors, and there is a lack of in-depth research in premenopausal breast cancer patients. We used 16S rRNA gene sequencing, targeted metabolomics, and cell culture methods to analyze the changes in the intestinal flora and metabolites of premenopausal breast cancer patients. In addition, we treated breast cancer cells with significantly altered propionate and butyrate in vitro to examine their effects on cell activity. This study followed STROBE guidelines. We found that compared with healthy premenopausal women, the composition and symbiosis of intestinal flora in patients with premenopausal breast cancer changed significantly. The abundance of short-chain fatty acid (SCFA)-producing bacteria was significantly reduced, and the key SCFA-producing enzymes were also significantly reduced. Pediococcus and Desulfovibrio could distinguish premenopausal breast cancer patients from normal premenopausal women. The related propionate and butyrate had a certain ability to inhibit breast cancer cell viability in vitro. As SCFA-producing bacteria, Pediococcus and Desulfovibrio showed potential reference value for the diagnosis of premenopausal breast cancer. The ability of propionate and butyrate to inhibit breast cancer cell lines in vitro suggests that the relevant SCFA receptor may be a new target for the treatment of premenopausal breast cancer.},
}
@article {pmid32934356,
year = {2021},
author = {Herrera, M and Klein, SG and Campana, S and Chen, JE and Prasanna, A and Duarte, CM and Aranda, M},
title = {Temperature transcends partner specificity in the symbiosis establishment of a cnidarian.},
journal = {The ISME journal},
volume = {15},
number = {1},
pages = {141-153},
pmid = {32934356},
issn = {1751-7370},
abstract = {Coral reef research has predominantly focused on the effect of temperature on the breakdown of coral-dinoflagellate symbioses. However, less is known about how increasing temperature affects the establishment of new coral-dinoflagellate associations. Inter-partner specificity and environment-dependent colonization are two constraints proposed to limit the acquisition of more heat tolerant symbionts. Here, we investigated the symbiotic dynamics of various photosymbionts in different host genotypes under "optimal" and elevated temperature conditions. To do this, we inoculated symbiont-free polyps of the sea anemone Exaiptasia pallida originating from Hawaii (H2), North Carolina (CC7), and the Red Sea (RS) with the same mixture of native symbiont strains (Breviolum minutum, Symbiodinium linucheae, S. microadriaticum, and a Breviolum type from the Red Sea) at 25 and 32 °C, and assessed their ITS2 composition, colonization rates, and PSII photochemical efficiency (Fv/Fm). Symbiont communities across thermal conditions differed significantly for all hosts, suggesting that temperature rather than partner specificity had a stronger effect on symbiosis establishment. Overall, we detected higher abundances of more heat resistant Symbiodiniaceae types in the 32 °C treatments. Our data further showed that PSII photophysiology under elevated temperature improved with thermal pre-exposure (i.e., higher Fv/Fm), yet, this effect depended on host genotype and was influenced by active feeding as photochemical efficiency dropped in response to food deprivation. These findings highlight the role of temperature and partner fidelity in the establishment and performance of symbiosis and demonstrate the importance of heterotrophy for symbiotic cnidarians to endure and recover from stress.},
}
@article {pmid32934115,
year = {2020},
author = {Ibarra-Juarez, LA and Burton, MAJ and Biedermann, PHW and Cruz, L and Desgarennes, D and Ibarra-Laclette, E and Latorre, A and Alonso-Sánchez, A and Villafan, E and Hanako-Rosas, G and López, L and Vázquez-Rosas-Landa, M and Carrion, G and Carrillo, D and Moya, A and Lamelas, A},
title = {Evidence for Succession and Putative Metabolic Roles of Fungi and Bacteria in the Farming Mutualism of the Ambrosia Beetle Xyleborus affinis.},
journal = {mSystems},
volume = {5},
number = {5},
pages = {},
pmid = {32934115},
issn = {2379-5077},
abstract = {The bacterial and fungal community involved in ambrosia beetle fungiculture remains poorly studied compared to the famous fungus-farming ants and termites. Here we studied microbial community dynamics of laboratory nests, adults, and brood during the life cycle of the sugarcane shot hole borer, Xyleborus affinis We identified a total of 40 fungal and 428 bacterial operational taxonomic units (OTUs), from which only five fungi (a Raffaelea fungus and four ascomycete yeasts) and four bacterial genera (Stenotrophomonas, Enterobacter, Burkholderia, and Ochrobactrum) can be considered the core community playing the most relevant symbiotic role. Both the fungal and bacterial populations varied significantly during the beetle's life cycle. While the ascomycete yeasts were the main colonizers of the gallery early on, the Raffaelea and other filamentous fungi appeared after day 10, at the time when larval hatching happened. Regarding bacteria, Stenotrophomonas and Enterobacter dominated overall but decreased in foundresses and brood with age. Finally, inferred analyses of the putative metabolic capabilities of the bacterial microbiome revealed that they are involved in (i) degradation of fungal and plant polymers, (ii) fixation of atmospheric nitrogen, and (iii) essential amino acid, cofactor, and vitamin provisioning. Overall, our results suggest that yeasts and bacteria are more strongly involved in supporting the beetle-fungus farming symbiosis than previously thought.IMPORTANCE Ambrosia beetles farm their own food fungi within tunnel systems in wood and are among the three insect lineages performing agriculture (the others are fungus-farming ants and termites). In ambrosia beetles, primary ambrosia fungus cultivars have been regarded essential, whereas other microbes have been more or less ignored. Our KEGG analyses suggest so far unknown roles of yeasts and bacterial symbionts, by preparing the tunnel walls for the primary ambrosia fungi. This preparation includes enzymatic degradation of wood, essential amino acid production, and nitrogen fixation. The latter is especially exciting because if it turns out to be present in vivo in ambrosia beetles, all farming animals (including humans) are dependent on atmospheric nitrogen fertilization of their crops. As previous internal transcribed spacer (ITS) metabarcoding approaches failed on covering the primary ambrosia fungi, our 18S metabarcoding approach can also serve as a template for future studies on the ambrosia beetle-fungus symbiosis.},
}
@article {pmid32934088,
year = {2020},
author = {Francoeur, CB and Khadempour, L and Moreira-Soto, RD and Gotting, K and Book, AJ and Pinto-Tomás, AA and Keefover-Ring, K and Currie, CR},
title = {Bacteria Contribute to Plant Secondary Compound Degradation in a Generalist Herbivore System.},
journal = {mBio},
volume = {11},
number = {5},
pages = {},
pmid = {32934088},
issn = {2150-7511},
support = {R01 GM083989/GM/NIGMS NIH HHS/United States ; T32 GM007133/GM/NIGMS NIH HHS/United States ; U19 AI142720/AI/NIAID NIH HHS/United States ; U19 TW009872/TW/FIC NIH HHS/United States ; },
abstract = {Herbivores must overcome a variety of plant defenses, including coping with plant secondary compounds (PSCs). To help detoxify these defensive chemicals, several insect herbivores are known to harbor gut microbiota with the metabolic capacity to degrade PSCs. Leaf-cutter ants are generalist herbivores, obtaining sustenance from specialized fungus gardens that act as external digestive systems and which degrade the diverse collection of plants foraged by the ants. There is in vitro evidence that certain PSCs harm Leucoagaricus gongylophorus, the fungal cultivar of leaf-cutter ants, suggesting a role for the Proteobacteria-dominant bacterial community present within fungus gardens. In this study, we investigated the ability of symbiotic bacteria present within fungus gardens of leaf-cutter ants to degrade PSCs. We cultured fungus garden bacteria, sequenced the genomes of 42 isolates, and identified genes involved in PSC degradation, including genes encoding cytochrome P450 enzymes and genes in geraniol, cumate, cinnamate, and α-pinene/limonene degradation pathways. Using metatranscriptomic analysis, we showed that some of these degradation genes are expressed in situ Most of the bacterial isolates grew unhindered in the presence of PSCs and, using gas chromatography-mass spectrometry (GC-MS), we determined that isolates from the genera Bacillus, Burkholderia, Enterobacter, Klebsiella, and Pseudomonas degrade α-pinene, β-caryophyllene, or linalool. Using a headspace sampler, we show that subcolonies of fungus gardens reduced α-pinene and linalool over a 36-h period, while L. gongylophorus strains alone reduced only linalool. Overall, our results reveal that the bacterial communities in fungus gardens play a pivotal role in alleviating the effect of PSCs on the leaf-cutter ant system.IMPORTANCE Leaf-cutter ants are dominant neotropical herbivores capable of deriving energy from a wide range of plant substrates. The success of leaf-cutter ants is largely due to their external gut, composed of key microbial symbionts, specifically, the fungal mutualist L. gongylophorus and a consistent bacterial community. Both symbionts are known to have critical roles in extracting energy from plant material, yet comparatively little is known about their roles in the detoxification of plant secondary compounds. In this study, we assessed if the bacterial communities associated with leaf-cutter ant fungus gardens can degrade harmful plant chemicals. We identify plant secondary compound detoxification in leaf-cutter ant gardens as a process that depends on the degradative potential of both the bacterial community and L. gongylophorus Our findings suggest that the fungus garden and its associated microbial community influence the generalist foraging abilities of the ants, underscoring the importance of microbial symbionts in plant substrate suitability for herbivores.},
}
@article {pmid32933105,
year = {2020},
author = {Kovaleva, O and Podlesnaya, P and Rashidova, M and Samoilova, D and Petrenko, A and Zborovskaya, I and Mochalnikova, V and Kataev, V and Khlopko, Y and Plotnikov, A and Gratchev, A},
title = {Lung Microbiome Differentially Impacts Survival of Patients with Non-Small Cell Lung Cancer Depending on Tumor Stroma Phenotype.},
journal = {Biomedicines},
volume = {8},
number = {9},
pages = {},
pmid = {32933105},
issn = {2227-9059},
support = {18-29-09069//Russian Foundation for Basic Research/ ; },
abstract = {The link between a lung tumor and the lung microbiome is a largely unexplored issue. To investigate the relationship between a lung microbiome and the phenotype of an inflammatory stromal infiltrate, we studied a cohort of 89 patients with non-small cell lung cancer. The microbiome was analyzed in tumor and adjacent normal tissue by 16S rRNA amplicon sequencing. Characterization of the tumor stroma was done using immunohistochemistry. We demonstrated that the bacterial load was higher in adjacent normal tissue than in a tumor (p = 0.0325) with similar patterns of taxonomic structure and alpha diversity. Lung adenocarcinomas did not differ in their alpha diversity from squamous cell carcinomas, although the content of Gram-positive bacteria increased significantly in the adenocarcinoma group (p = 0.0419). An analysis of an inflammatory infiltrate of tumor stroma showed a correlation of CD68, iNOS and FOXP3 with a histological type of tumor. For the first time we showed that high bacterial load in the tumor combined with increased iNOS expression is a favorable prognostic factor (HR = 0.1824; p = 0.0123), while high bacterial load combined with the increased number of FOXP3+ cells is a marker of poor prognosis (HR = 4.651; p = 0.0116). Thus, we established that bacterial load of the tumor has an opposite prognostic value depending on the status of local antitumor immunity.},
}
@article {pmid32929496,
year = {2020},
author = {Wanke, A and Malisic, M and Wawra, S and Zuccaro, A},
title = {Unraveling the sugar code: the role of microbial extracellular glycans in plant-microbe interactions.},
journal = {Journal of experimental botany},
volume = {},
number = {},
pages = {},
doi = {10.1093/jxb/eraa414},
pmid = {32929496},
issn = {1460-2431},
abstract = {To defend against microbial invad