37 research outputs found

    Scholarly Communications Journal Club Syllabus

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    This Medical Library Association Journal Club was conducted at the Health Sciences Library and Informatics Center at the University of New Mexico from August 2015 - May 2016. Ten topics within scholarly communications were studied, including an introduction and background to scholarly communications, academic publishing and the role of publishers, digital curation and preservation, copyright, open access and the role of peer review, scholarly communication in libraries, scholarly impact and metrics, and open educational resources (OERs). The readings for each topic are included, many of which are open access publications

    Transmission of Single HIV-1 Genomes and Dynamics of Early Immune Escape Revealed by Ultra-Deep Sequencing

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    We used ultra-deep sequencing to obtain tens of thousands of HIV-1 sequences from regions targeted by CD8+ T lymphocytes from longitudinal samples from three acutely infected subjects, and modeled viral evolution during the critical first weeks of infection. Previous studies suggested that a single virus established productive infection, but these conclusions were tempered because of limited sampling; now, we have greatly increased our confidence in this observation through modeling the observed earliest sample diversity based on vastly more extensive sampling. Conventional sequencing of HIV-1 from acute/early infection has shown different patterns of escape at different epitopes; we investigated the earliest escapes in exquisite detail. Over 3–6 weeks, ultradeep sequencing revealed that the virus explored an extraordinary array of potential escape routes in the process of evading the earliest CD8 T-lymphocyte responses – using 454 sequencing, we identified over 50 variant forms of each targeted epitope during early immune escape, while only 2–7 variants were detected in the same samples via conventional sequencing. In contrast to the diversity seen within epitopes, non-epitope regions, including the Envelope V3 region, which was sequenced as a control in each subject, displayed very low levels of variation. In early infection, in the regions sequenced, the consensus forms did not have a fitness advantage large enough to trigger reversion to consensus amino acids in the absence of immune pressure. In one subject, a genetic bottleneck was observed, with extensive diversity at the second time point narrowing to two dominant escape forms by the third time point, all within two months of infection. Traces of immune escape were observed in the earliest samples, suggesting that immune pressure is present and effective earlier than previously reported; quantifying the loss rate of the founder virus suggests a direct role for CD8 T-lymphocyte responses in viral containment after peak viremia. Dramatic shifts in the frequencies of epitope variants during the first weeks of infection revealed a complex interplay between viral fitness and immune escape

    Capturing Single Cell Genomes of Active Polysaccharide Degraders: An Unexpected Contribution of Verrucomicrobia

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    Microbial hydrolysis of polysaccharides is critical to ecosystem functioning and is of great interest in diverse biotechnological applications, such as biofuel production and bioremediation. Here we demonstrate the use of a new, efficient approach to recover genomes of active polysaccharide degraders from natural, complex microbial assemblages, using a combination of fluorescently labeled substrates, fluorescence-activated cell sorting, and single cell genomics. We employed this approach to analyze freshwater and coastal bacterioplankton for degraders of laminarin and xylan, two of the most abundant storage and structural polysaccharides in nature. Our results suggest that a few phylotypes of Verrucomicrobia make a considerable contribution to polysaccharide degradation, although they constituted only a minor fraction of the total microbial community. Genomic sequencing of five cells, representing the most predominant, polysaccharide-active Verrucomicrobia phylotype, revealed significant enrichment in genes encoding a wide spectrum of glycoside hydrolases, sulfatases, peptidases, carbohydrate lyases and esterases, confirming that these organisms were well equipped for the hydrolysis of diverse polysaccharides. Remarkably, this enrichment was on average higher than in the sequenced representatives of Bacteroidetes, which are frequently regarded as highly efficient biopolymer degraders. These findings shed light on the ecological roles of uncultured Verrucomicrobia and suggest specific taxa as promising bioprospecting targets. The employed method offers a powerful tool to rapidly identify and recover discrete genomes of active players in polysaccharide degradation, without the need for cultivation

    Forest floor community metatranscriptomes identify fungal and bacterial responses to N deposition in two maple forests

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    Anthropogenic N deposition alters patterns of C and N cycling in temperate forests, where forest floor litter decomposition is a key process mediated by a diverse community of bacteria and fungi. To track forest floor decomposer activity we generated metatranscriptomes that simultaneously surveyed the actively expressed bacterial and eukaryote genes in the forest floor, to compare the impact of N deposition on the decomposers in two natural maple forests in Michigan, USA, where replicate field plots had been amended with N for 16 years. Site and N amendment responses were compared using about 75,000 carbohydrate active enzyme transcript sequences (CAZymes) in each metatranscriptome. Parallel ribosomal RNA surveys of bacterial and fungal biomass and taxonomic composition showed no significant differences in either biomass or OTU richness between the two sites or in response to N. Site and N amendment were not significant variables defining bacterial taxonomic composition, but they were significant for fungal community composition, explaining 17 and 14% of the variability, respectively. The relative abundance of expressed bacterial and fungal CAZymes changed significantly with N amendment in one of the forests, and N-response trends were also identified in the second forest. Although the two ambient forests were similar in community biomass, taxonomic structure and active CAZyme profile, the shifts in active CAZyme profiles in response to N-amendment differed between the sites. One site responded with an over-expression of bacterial CAZymes, and the other site responded with an over-expression of both fungal and different bacterial CAZymes. Both sites showed reduced representation of fungal lignocellulose degrading enzymes in N-amendment plots. The metatranscriptome approach provided a holistic assessment of eukaryote and bacterial gene expression and is applicable to other systems where eukaryotes and bacteria interact

    A metagenomic viral discovery approach identifies potential zoonotic and novel mammalian viruses in <i>Neoromicia</i> bats within South Africa

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    <div><p>Species within the <i>Neoromicia</i> bat genus are abundant and widely distributed in Africa. It is common for these insectivorous bats to roost in anthropogenic structures in urban regions. Additionally, <i>Neoromicia capensis</i> have previously been identified as potential hosts for Middle East respiratory syndrome (MERS)-related coronaviruses. This study aimed to ascertain the gastrointestinal virome of these bats, as viruses excreted in fecal material or which may be replicating in rectal or intestinal tissues have the greatest opportunities of coming into contact with other hosts. Samples were collected in five regions of South Africa over eight years. Initial virome composition was determined by viral metagenomic sequencing by pooling samples and enriching for viral particles. Libraries were sequenced on the Illumina MiSeq and NextSeq500 platforms, producing a combined 37 million reads. Bioinformatics analysis of the high throughput sequencing data detected the full genome of a novel species of the <i>Circoviridae</i> family, and also identified sequence data from the <i>Adenoviridae</i>, <i>Coronaviridae</i>, <i>Herpesviridae</i>, <i>Parvoviridae</i>, <i>Papillomaviridae</i>, <i>Phenuiviridae</i>, and <i>Picornaviridae</i> families. Metagenomic sequencing data was insufficient to determine the viral diversity of certain families due to the fragmented coverage of genomes and lack of suitable sequencing depth, as some viruses were detected from the analysis of reads-data only. Follow up conventional PCR assays targeting conserved gene regions for the <i>Adenoviridae</i>, <i>Coronaviridae</i>, and <i>Herpesviridae</i> families were used to confirm metagenomic data and generate additional sequences to determine genetic diversity. The complete coding genome of a MERS-related coronavirus was recovered with additional amplicon sequencing on the MiSeq platform. The new genome shared 97.2% overall nucleotide identity to a previous <i>Neoromicia</i>-associated MERS-related virus, also from South Africa. Conventional PCR analysis detected diverse adenovirus and herpesvirus sequences that were widespread throughout <i>Neoromicia</i> populations in South Africa. Furthermore, similar adenovirus sequences were detected within these populations throughout several years. With the exception of the coronaviruses, the study represents the first report of sequence data from several viral families within a Southern African insectivorous bat genus; highlighting the need for continued investigations in this regard.</p></div

    Novel <i>Neoromicia</i> picornavirus.

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    <p><b>A)</b> Overview of the confirmed picornavirus contig alignment positions in reference to a typical picornavirus genome. The dark grey contig (1077bp) of the P1/P2 region was used to construct a Bayesian phylogeny. <b>B)</b> The maximum clade credibility tree constructed in BEAST v1.8 used the GTR plus invariant sites and gamma distribution substitution model. The genera are indicated on the right side of the sequence names (with GenBank accession numbers); the <i>Neoromicia</i> picornavirus from this study is indicated with a black circle. Posterior probability values of less than 50% were omitted.</p

    Map of Africa depicting the overlapping distributions of dromedary camels and cape serotine bats as hosts of MERS and related coronaviruses.

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    <p>The map was constructed in ArcMap v.10.4.1. The geographic distribution of dromedary camels are depicted with horizontal lines, with seroprevalence data of MERS antibodies detected from surveillance activities in camels shown with crossed lines. The distributions of <i>N</i>. <i>capensis</i> were taken from museum collections (point data) and thus extrapolated as modelled data. Clipart images of camels or bats show where viral RNA of MERS and MERS-related strains and have been reported.</p

    <i>Phenuiviridae</i> sequence identified from the <i>Neoromicia</i> virome.

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    <p><b>A)</b> Alignment of the <i>Phenuiviridae</i> contig in reference to a typical L segment gene. <b>B)</b> The phylogenetic tree was constructed with a 267 bp region of the bunyavirus L genome segment using BEAST v1.8 with the GTR substitution model plus invariant sites. Relevant genera are shown on the right and GenBank accession numbers of each sequence are provided; the novel <i>Neoromicia</i> bunyavirus sequence from this study is indicated with a black circle. SFTSV = Severe fever with thrombocytopenia syndrome virus.</p

    Strategies for sample pooling and data analysis workflows.

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    <p><b>A)</b> The workflow depicts the sample pooling strategies utilized in the study. Faecal and rectal samples were primarily pooled for initial viral metagenomic sample processing. Subsequently, remaining sample material (faecal homogenates, rectum, or intestine) available for individual bats were pooled according to species and location to associate selected viral families with specific species. A further step was implemented to determine specific host individuals harbouring coronaviruses in order to clarify exact sampling locations. <b>B)</b> Bioinformatics data analysis of Illumina reads with a developed workflow in CLC genomic workbench that trims data for quality, removes adaptors and depletes host reads based on set mapping parameters. Remaining reads were taxonomically assigned with BLASTn and MEGAN v6. <b>C)</b> Shows the BLASTn assignments of reads according to virus genome types: ssRNA, ssDNA and dsDNA viruses.</p
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