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  1. Article ; Online: Assessment of fungal spores and spore-like diversity in environmental samples by targeted lysis.

    Corona Ramirez, Andrea / Bregnard, Danaé / Junier, Thomas / Cailleau, Guillaume / Dorador, Cristina / Bindschedler, Saskia / Junier, Pilar

    BMC microbiology

    2023  Volume 23, Issue 1, Page(s) 68

    Abstract: At particular stages during their life cycles, fungi use multiple strategies to form specialized structures to survive unfavorable environmental conditions. These strategies encompass sporulation, as well as cell-wall melanization, multicellular tissue ... ...

    Abstract At particular stages during their life cycles, fungi use multiple strategies to form specialized structures to survive unfavorable environmental conditions. These strategies encompass sporulation, as well as cell-wall melanization, multicellular tissue formation or even dimorphism. The resulting structures are not only used to disperse to other environments, but also to survive long periods of time awaiting favorable growth conditions. As a result, these specialized fungal structures are part of the microbial seed bank, which is known to influence the microbial community composition and contribute to the maintenance of diversity. Despite the importance of the microbial seed bank in the environment, methods to study the diversity of fungal structures with improved resistance only target spores dispersing in the air, omitting the high diversity of these structures in terms of morphology and environmental distribution. In this study, we applied a separation method based on cell lysis to enrich lysis-resistant fungal structures (for instance, spores, sclerotia, melanized yeast) to obtain a proxy of the composition of the fungal seed bank. This approach was first evaluated in-vitro in selected species. The results obtained showed that DNA from fungal spores and from yeast was only obtained after the application of the enrichment method, while mycelium was always lysed. After validation, we compared the diversity of the total and lysis-resistant fractions in the polyextreme environment of the Salar de Huasco, a high-altitude athalassohaline wetland in the Chilean Altiplano. Environmental samples were collected from the salt flat and from microbial mats in small surrounding ponds. Both the lake sediments and microbial mats were dominated by Ascomycota and Basidiomycota, however, the diversity and composition of each environment differed at lower taxonomic ranks. Members of the phylum Chytridiomycota were enriched in the lysis-resistant fraction, while members of the phylum Rozellomycota were never detected in this fraction. Moreover, we show that the community composition of the lysis-resistant fraction reflects the diversity of life cycles and survival strategies developed by fungi in the environment. To the best of our knowledge this is the first time that the fungal diversity is explored in the Salar de Huasco. In addition, the method presented here provides a simple and culture independent approach to assess the diversity of fungal lysis-resistant cells in the environment.
    MeSH term(s) Ascomycota/genetics ; Ascomycota/physiology ; Basidiomycota/genetics ; Basidiomycota/physiology ; Chile ; Fungi/genetics ; Fungi/physiology ; Geologic Sediments/microbiology ; Lakes/microbiology ; Microbiota/physiology ; Mycelium/genetics ; Mycelium/isolation & purification ; Mycelium/physiology ; Mycobiome/physiology ; Saccharomyces cerevisiae/genetics ; Saccharomyces cerevisiae/physiology ; Spores, Fungal/genetics ; Spores, Fungal/isolation & purification ; Spores, Fungal/physiology ; Wetlands ; DNA, Fungal/genetics ; DNA, Fungal/isolation & purification ; DNA, Fungal/physiology
    Chemical Substances DNA, Fungal
    Language English
    Publishing date 2023-03-14
    Publishing country England
    Document type Journal Article ; Research Support, Non-U.S. Gov't
    ZDB-ID 2041505-9
    ISSN 1471-2180 ; 1471-2180
    ISSN (online) 1471-2180
    ISSN 1471-2180
    DOI 10.1186/s12866-023-02809-w
    Database MEDical Literature Analysis and Retrieval System OnLINE

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  2. Article: Transit Shadows

    Junier, Thomas / Pilar Junier

    Science. 2013 Apr. 26, v. 340, no. 6131

    2013  

    Abstract: This exhibition celebrating superconductivity features sculptures by Etienne Krähenbühl that reveal fresh mechanical and artistic possibilities of metal alloys. ...

    Abstract This exhibition celebrating superconductivity features sculptures by Etienne Krähenbühl that reveal fresh mechanical and artistic possibilities of metal alloys.
    Keywords alloys
    Language English
    Dates of publication 2013-0426
    Size p. 433.
    Publishing place American Association for the Advancement of Science
    Document type Article
    ZDB-ID 128410-1
    ISSN 1095-9203 ; 0036-8075
    ISSN (online) 1095-9203
    ISSN 0036-8075
    DOI 10.1126/science.1237128
    Database NAL-Catalogue (AGRICOLA)

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  3. Article ; Online: CEGA--a catalog of conserved elements from genomic alignments.

    Dousse, Aline / Junier, Thomas / Zdobnov, Evgeny M

    Nucleic acids research

    2016  Volume 44, Issue D1, Page(s) D96–100

    Abstract: By identifying genomic sequence regions conserved among several species, comparative genomics offers opportunities to discover putatively functional elements without any prior knowledge of what these functions might be. Comparative analyses across ... ...

    Abstract By identifying genomic sequence regions conserved among several species, comparative genomics offers opportunities to discover putatively functional elements without any prior knowledge of what these functions might be. Comparative analyses across mammals estimated 4-5% of the human genome to be functionally constrained, a much larger fraction than the 1-2% occupied by annotated protein-coding or RNA genes. Such functionally constrained yet unannotated regions have been referred to as conserved non-coding sequences (CNCs) or ultra-conserved elements (UCEs), which remain largely uncharacterized but probably form a highly heterogeneous group of elements including enhancers, promoters, motifs, and others. To facilitate the study of such CNCs/UCEs, we present our resource of Conserved Elements from Genomic Alignments (CEGA), accessible from http://cega.ezlab.org. Harnessing the power of multiple species comparisons to detect genomic elements under purifying selection, CEGA provides a comprehensive set of CNCs identified at different radiations along the vertebrate lineage. Evolutionary constraint is identified using threshold-free phylogenetic modeling of unbiased and sensitive global alignments of genomic synteny blocks identified using protein orthology. We identified CNCs independently for five vertebrate clades, each referring to a different last common ancestor and therefore to an overlapping but varying set of CNCs with 24 488 in vertebrates, 241 575 in amniotes, 709 743 in Eutheria, 642 701 in Boreoeutheria and 612 364 in Euarchontoglires, spanning from 6 Mbp in vertebrates to 119 Mbp in Euarchontoglires. The dynamic CEGA web interface displays alignments, genomic locations, as well as biologically relevant data to help prioritize and select CNCs of interest for further functional investigations.
    MeSH term(s) Animals ; Conserved Sequence ; Databases, Nucleic Acid ; Genomics ; Humans ; Mice ; Rats ; Sequence Alignment ; Synteny
    Language English
    Publishing date 2016-01-04
    Publishing country England
    Document type Journal Article ; Research Support, Non-U.S. Gov't
    ZDB-ID 186809-3
    ISSN 1362-4962 ; 1362-4954 ; 0301-5610 ; 0305-1048
    ISSN (online) 1362-4962 ; 1362-4954
    ISSN 0301-5610 ; 0305-1048
    DOI 10.1093/nar/gkv1163
    Database MEDical Literature Analysis and Retrieval System OnLINE

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  4. Article ; Online: Joint host-pathogen genomic analysis identifies hepatitis B virus mutations associated with human NTCP and HLA class I variation.

    Xu, Zhi Ming / Gnouamozi, Gnimah Eva / Rüeger, Sina / Shea, Patrick R / Buti, Maria / Chan, Henry Ly / Marcellin, Patrick / Lawless, Dylan / Naret, Olivier / Zeller, Matthias / Schneuing, Arne / Scheck, Andreas / Junier, Thomas / Moradpour, Darius / Podlaha, Ondrej / Suri, Vithika / Gaggar, Anuj / Subramanian, Mani / Correia, Bruno /
    Gfeller, David / Urban, Stephan / Fellay, Jacques

    American journal of human genetics

    2024  

    Abstract: Evolutionary changes in the hepatitis B virus (HBV) genome could reflect its adaptation to host-induced selective pressure. Leveraging paired human exome and ultra-deep HBV genome-sequencing data from 567 affected individuals with chronic hepatitis B, we ...

    Abstract Evolutionary changes in the hepatitis B virus (HBV) genome could reflect its adaptation to host-induced selective pressure. Leveraging paired human exome and ultra-deep HBV genome-sequencing data from 567 affected individuals with chronic hepatitis B, we comprehensively searched for the signatures of this evolutionary process by conducting "genome-to-genome" association tests between all human genetic variants and viral mutations. We identified significant associations between an East Asian-specific missense variant in the gene encoding the HBV entry receptor NTCP (rs2296651, NTCP S267F) and mutations within the receptor-binding region of HBV preS1. Through in silico modeling and in vitro preS1-NTCP binding assays, we observed that the associated HBV mutations are in proximity to the NTCP variant when bound and together partially increase binding affinity to NTCP S267F. Furthermore, we identified significant associations between HLA-A variation and viral mutations in HLA-A-restricted T cell epitopes. We used in silico binding prediction tools to evaluate the impact of the associated HBV mutations on HLA presentation and observed that mutations that result in weaker binding affinities to their cognate HLA alleles were enriched. Overall, our results suggest the emergence of HBV escape mutations that might alter the interaction between HBV PreS1 and its cellular receptor NTCP during viral entry into hepatocytes and confirm the role of HLA class I restriction in inducing HBV epitope variations.
    Language English
    Publishing date 2024-05-07
    Publishing country United States
    Document type Journal Article
    ZDB-ID 219384-x
    ISSN 1537-6605 ; 0002-9297
    ISSN (online) 1537-6605
    ISSN 0002-9297
    DOI 10.1016/j.ajhg.2024.04.013
    Database MEDical Literature Analysis and Retrieval System OnLINE

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  5. Article ; Online: MLgsc: A Maximum-Likelihood General Sequence Classifier.

    Junier, Thomas / Hervé, Vincent / Wunderlin, Tina / Junier, Pilar

    PloS one

    2015  Volume 10, Issue 7, Page(s) e0129384

    Abstract: We present software package for classifying protein or nucleotide sequences to user-specified sets of reference sequences. The software trains a model using a multiple sequence alignment and a phylogenetic tree, both supplied by the user. The latter is ... ...

    Abstract We present software package for classifying protein or nucleotide sequences to user-specified sets of reference sequences. The software trains a model using a multiple sequence alignment and a phylogenetic tree, both supplied by the user. The latter is used to guide model construction and as a decision tree to speed up the classification process. The software was evaluated on all the 16S rRNA gene sequences of the reference dataset found in the GreenGenes database. On this dataset, the software was shown to achieve an error rate of around 1% at genus level. Examples of applications based on the nitrogenase subunit NifH gene and a protein-coding gene found in endospore-forming Firmicutes is also presented. The programs in the package have a simple, straightforward command-line interface for the Unix shell, and are free and open-source. The package has minimal dependencies and thus can be easily integrated in command-line based classification pipelines.
    MeSH term(s) Databases, Genetic ; Databases, Protein ; Likelihood Functions ; Nucleotides/chemistry ; Phylogeny ; Proteins/chemistry ; Software
    Chemical Substances Nucleotides ; Proteins
    Language English
    Publishing date 2015-07-06
    Publishing country United States
    Document type Journal Article ; Research Support, Non-U.S. Gov't ; Validation Study
    ISSN 1932-6203
    ISSN (online) 1932-6203
    DOI 10.1371/journal.pone.0129384
    Database MEDical Literature Analysis and Retrieval System OnLINE

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  6. Article ; Online: Viral Genetic Determinants of Prolonged Respiratory Syncytial Virus Infection Among Infants in a Healthy Term Birth Cohort.

    Lawless, Dylan / McKennan, Christopher G / Das, Suman R / Junier, Thomas / Xu, Zhi Ming / Anderson, Larry J / Gebretsadik, Tebeb / Shilts, Meghan H / Larkin, Emma / Rosas-Salazar, Christian / Chappell, James D / Fellay, Jacques / Hartert, Tina V

    The Journal of infectious diseases

    2022  Volume 227, Issue 10, Page(s) 1194–1202

    Abstract: Background: Respiratory syncytial virus (RSV) is associated with acute respiratory infection. We sought to identify RSV variants associated with prolonged infection.: Methods: Among healthy term infants we identified those with prolonged RSV ... ...

    Abstract Background: Respiratory syncytial virus (RSV) is associated with acute respiratory infection. We sought to identify RSV variants associated with prolonged infection.
    Methods: Among healthy term infants we identified those with prolonged RSV infection and conducted (1) a human genome-wide association study (GWAS) to test the dependence of infection risk on host genotype, (2) a viral GWAS for association with prolonged RSV infection using RSV whole-genome sequencing, (3) an analysis of all viral public sequences, (4) an assessment of immunological responses, and (5) a summary of all major functional data. Analyses were adjusted for viral/human population structure and host factors associated with infection risk.
    Results: We identified p.E123K/D and p.P218T/S/L in G protein that were associated with prolonged infection (Padj = .01). We found no evidence of host genetic risk for infection. The RSV variant positions approximate sequences that could bind a putative viral receptor, heparan sulfate.
    Conclusions: Using analysis of both viral and host genetics we identified a novel RSV variant associated with prolonged infection in otherwise healthy infants and no evidence supporting host genetic susceptibility to infection. As the capacity of RSV for chronicity and its viral reservoir are not defined, these findings are important for understanding the impact of RSV on chronic disease and endemicity.
    MeSH term(s) Humans ; Infant ; Respiratory Syncytial Virus Infections/epidemiology ; Respiratory Syncytial Virus Infections/genetics ; Birth Cohort ; Genome-Wide Association Study ; Respiratory Syncytial Virus, Human/genetics ; Genetic Predisposition to Disease
    Language English
    Publishing date 2022-11-14
    Publishing country United States
    Document type Journal Article ; Research Support, N.I.H., Extramural ; Research Support, Non-U.S. Gov't
    ZDB-ID 3019-3
    ISSN 1537-6613 ; 0022-1899
    ISSN (online) 1537-6613
    ISSN 0022-1899
    DOI 10.1093/infdis/jiac442
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  7. Article: Virosaurus A Reference to Explore and Capture Virus Genetic Diversity

    Gleizes, Anne / Laubscher, Florian / Guex, Nicolas / Iseli, Christian / Junier, Thomas / Cordey, Samuel / Fellay, Jacques / Xenarios, Ioannis / Kaiser, Laurent / Mercier, Philippe Le

    Viruses. 2020 Nov. 01, v. 12, no. 11

    2020  

    Abstract: The huge genetic diversity of circulating viruses is a challenge for diagnostic assays for emerging or rare viral diseases. High-throughput technology offers a new opportunity to explore the global virome of patients without preconception about the ... ...

    Abstract The huge genetic diversity of circulating viruses is a challenge for diagnostic assays for emerging or rare viral diseases. High-throughput technology offers a new opportunity to explore the global virome of patients without preconception about the culpable pathogens. It requires a solid reference dataset to be accurate. Virosaurus has been designed to offer a non-biased, automatized and annotated database for clinical metagenomics studies and diagnosis. Raw viral sequences have been extracted from GenBank, and cleaned up to remove potentially erroneous sequences. Complete sequences have been identified for all genera infecting vertebrates, plants and other eukaryotes (insect, fungus, etc.). To facilitate the analysis of clinically relevant viruses, we have annotated all sequences with official and common virus names, acronym, genotypes, and genomic features (linear, circular, DNA, RNA, etc.). Sequences have been clustered to remove redundancy at 90% or 98% identity. The analysis of clustering results reveals the state of the virus genetic landscape knowledge. Because herpes and poxviruses were under-represented in complete genomes considering their potential diversity in nature, we used genes instead of complete genomes for those in Virosaurus.
    Keywords DNA ; Poxviridae ; RNA ; cleaning ; data collection ; databases ; eukaryotic cells ; fungi ; genes ; genetic variation ; genotype ; insects ; landscape genetics ; metagenomics ; pathogens ; patients ; vertebrates ; viruses
    Language English
    Dates of publication 2020-1101
    Publishing place Multidisciplinary Digital Publishing Institute
    Document type Article
    ZDB-ID 2516098-9
    ISSN 1999-4915
    ISSN 1999-4915
    DOI 10.3390/v12111248
    Database NAL-Catalogue (AGRICOLA)

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  8. Article ; Online: Physical Isolation of Endospores from Environmental Samples by Targeted Lysis of Vegetative Cells.

    Wunderlin, Tina / Junier, Thomas / Paul, Christophe / Jeanneret, Nicole / Junier, Pilar

    Journal of visualized experiments : JoVE

    2016  , Issue 107, Page(s) e53411

    Abstract: Endospore formation is a survival strategy found among some bacteria from the phylum Firmicutes. During endospore formation, these bacteria enter a morpho-physiological resting state that enhances survival under adverse environmental conditions. Even ... ...

    Abstract Endospore formation is a survival strategy found among some bacteria from the phylum Firmicutes. During endospore formation, these bacteria enter a morpho-physiological resting state that enhances survival under adverse environmental conditions. Even though endospore-forming Firmicutes are one of the most frequently enriched and isolated bacterial groups in culturing studies, they are often absent from diversity studies based on molecular methods. The resistance of the spore core is considered one of the factors limiting the recovery of DNA from endospores. We developed a method that takes advantage of the higher resistance of endospores to separate them from other cells in a complex microbial community using physical, enzymatic and chemical lysis methods. The endospore-only preparation thus obtained can be used for re-culturing or to perform downstream analysis such as tailored DNA extraction optimized for endospores and subsequent DNA sequencing. This method, applied to sediment samples, has allowed the enrichment of endospores and after sequencing, has revealed a large diversity of endospore-formers in freshwater lake sediments. We expect that the application of this method to other samples will yield a similar outcome.
    MeSH term(s) DNA, Bacterial/analysis ; Environmental Microbiology ; Sequence Analysis, DNA ; Spores, Bacterial/genetics ; Spores, Bacterial/isolation & purification
    Chemical Substances DNA, Bacterial
    Language English
    Publishing date 2016-01-21
    Publishing country United States
    Document type Journal Article ; Research Support, Non-U.S. Gov't ; Video-Audio Media
    ISSN 1940-087X
    ISSN (online) 1940-087X
    DOI 10.3791/53411
    Database MEDical Literature Analysis and Retrieval System OnLINE

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  9. Article ; Online: Diversity and ecology of oxalotrophic bacteria.

    Hervé, Vincent / Junier, Thomas / Bindschedler, Saskia / Verrecchia, Eric / Junier, Pilar

    World journal of microbiology & biotechnology

    2016  Volume 32, Issue 2, Page(s) 28

    Abstract: Oxalate is present in environments as diverse as soils or gastrointestinal tracts. This organic acid can be found as free acid or forming metal salts (e.g. calcium, magnesium). Oxalotrophy, the ability to use oxalate as carbon and energy sources, is ... ...

    Abstract Oxalate is present in environments as diverse as soils or gastrointestinal tracts. This organic acid can be found as free acid or forming metal salts (e.g. calcium, magnesium). Oxalotrophy, the ability to use oxalate as carbon and energy sources, is mainly the result of bacterial catabolism, which can be either aerobic or anaerobic. Although some oxalotrophic bacterial strains are commonly used as probiotics, little is known about the diversity and ecology of this functional group. This review aims at exploring the taxonomic distribution and the phylogenetic diversity of oxalotrophic bacteria across biomes. In silico analyses were conducted using the two key enzymes involved in oxalotrophy: formyl-coenzyme A (CoA) transferase (EC 2.8.3.16) and oxalyl-CoA decarboxylase (EC 4.1.1.8), encoded by the frc and oxc genes, respectively. Our analyses revealed that oxalate-degrading bacteria are restricted to three phyla, namely Actinobacteria, Firmicutes and Proteobacteria and originated from terrestrial, aquatic and clinical environments. Diversity analyses at the protein level suggest that total Oxc diversity is more constrained than Frc diversity and that bacterial oxalotrophic diversity is not yet fully described. Finally, the contribution of oxalotrophic bacteria to ecosystem functioning as well as to the carbon cycle is discussed.
    MeSH term(s) Actinobacteria/classification ; Actinobacteria/genetics ; Actinobacteria/metabolism ; Acyl Coenzyme A/genetics ; Acyl Coenzyme A/metabolism ; Animals ; Biodiversity ; Carboxy-Lyases/genetics ; Carboxy-Lyases/metabolism ; Ecology ; Firmicutes/classification ; Firmicutes/genetics ; Firmicutes/metabolism ; Gastrointestinal Tract/chemistry ; Gastrointestinal Tract/microbiology ; Humans ; Oxalates/metabolism ; Proteobacteria/classification ; Proteobacteria/genetics ; Proteobacteria/metabolism ; Soil/chemistry ; Soil Microbiology
    Chemical Substances Acyl Coenzyme A ; Oxalates ; Soil ; formyl-coenzyme A (13131-49-2) ; Carboxy-Lyases (EC 4.1.1.-) ; oxalyl CoA decarboxylase (EC 4.1.1.8)
    Language English
    Publishing date 2016-02
    Publishing country Germany
    Document type Journal Article ; Review
    ZDB-ID 1499109-3
    ISSN 1573-0972 ; 0959-3993
    ISSN (online) 1573-0972
    ISSN 0959-3993
    DOI 10.1007/s11274-015-1982-3
    Database MEDical Literature Analysis and Retrieval System OnLINE

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  10. Article ; Online: The Newick utilities: high-throughput phylogenetic tree processing in the UNIX shell.

    Junier, Thomas / Zdobnov, Evgeny M

    Bioinformatics (Oxford, England)

    2010  Volume 26, Issue 13, Page(s) 1669–1670

    Abstract: Summary: We present a suite of Unix shell programs for processing any number of phylogenetic trees of any size. They perform frequently-used tree operations without requiring user interaction. They also allow tree drawing as scalable vector graphics ( ... ...

    Abstract Summary: We present a suite of Unix shell programs for processing any number of phylogenetic trees of any size. They perform frequently-used tree operations without requiring user interaction. They also allow tree drawing as scalable vector graphics (SVG), suitable for high-quality presentations and further editing, and as ASCII graphics for command-line inspection. As an example we include an implementation of bootscanning, a procedure for finding recombination breakpoints in viral genomes.
    Availability: C source code, Python bindings and executables for various platforms are available from http://cegg.unige.ch/newick_utils. The distribution includes a manual and example data. The package is distributed under the BSD License.
    Contact: thomas.junier@unige.ch
    MeSH term(s) Computational Biology/methods ; Computer Graphics ; Likelihood Functions ; Phylogeny ; Programming Languages ; Sequence Alignment ; Software
    Language English
    Publishing date 2010-05-13
    Publishing country England
    Document type Journal Article ; Research Support, Non-U.S. Gov't
    ZDB-ID 1422668-6
    ISSN 1367-4811 ; 1367-4803
    ISSN (online) 1367-4811
    ISSN 1367-4803
    DOI 10.1093/bioinformatics/btq243
    Database MEDical Literature Analysis and Retrieval System OnLINE

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