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Bomberger, J. M.

Publications and source records attributed to Bomberger, J. M..

3 recordsLinked to original sources

SprayNPray: user-friendly taxonomic profiling of genome and metagenome contigs

Shotgun sequencing of cultured microbial isolates/individual eukaryotes (whole-genome sequencing) and microbial communities (metagenomics) has become commonplace in biology. Very often, sequenced samples encompass organisms spanning multiple domains of life, necessitating increasingly elaborate software for accurate taxonomic classification of assembled sequences. While many software tools for taxonomic classification exist, SprayNPray offers a quick and user-friendly, semiautomated approach, allowing users to separate contigs by taxonomy (and other metrics) of interest. Easy installation, usage, and intuitive output, which is amenable to visual inspection and/or further computational parsing, will reduce barriers for biologists beginning to analyze genomes and metagenomes. This approach can be used for broad-level overviews, preliminary analyses, or as a supplement to other taxonomic classification or binning software. SprayNPray profiles contigs using multiple metrics, including closest homologs from a user-specified reference database, gene density, read coverage, GC content, tetranucleotide frequency, and codon-usage bias. The output from this software is designed to allow users to spot-check metagenome-assembled genomes, identify, and remove contigs from putative contaminants in isolate assemblies, identify bacteria in eukaryotic assemblies (and vice-versa), and identify possible horizontal gene transfer events.

bioinformatics

Genomic and functional characterization of Pseudomonas aeruginosa-targeting bacteriophages isolated from hospital wastewater

Pseudomonas aeruginosa infections can be difficult to treat and new therapeutic approaches are needed. Bacteriophage therapy is a promising alternative to traditional antibiotics, but large numbers of isolated and characterized phages are lacking. We collected 23 genetically and phenotypically diverse P. aeruginosa isolates from people with cystic fibrosis (CF) and clinical infections, and characterized their genetic, phenotypic, and prophage diversity. We then used these isolates to screen and isolate 14 new P. aeruginosa-targeting phages from hospital wastewater. Phages were characterized with genome sequencing, comparative genomics, and lytic activity screening against all 23 bacterial host isolates. For four different phages, we evolved bacterial mutants that were resistant to phage infection. We then used genome sequencing and functional analysis of the resistant mutants to study their mechanisms of phage resistance as well as changes in virulence factor production and antibiotic resistance, which differed from corresponding parent bacterial isolates. Finally, we tested two phages for their ability to kill P. aeruginosa grown in biofilms in vitro, and observed that both phages reduced viable bacteria in biofilms by least one order of magnitude. One of these phages also showed activity against P. aeruginosa biofilms grown on CF airway epithelial cells. Overall, this study demonstrates how systematic genomic and phenotypic characterization can be deployed to develop bacteriophages as precision antibiotics.

microbiology

Evolution and adaptation of Pseudomonas aeruginosa in the paranasal sinuses of people with cystic fibrosis

People with the genetic disorder cystic fibrosis (CF) harbor lifelong respiratory infections, with morbidity and mortality frequently linked to chronic lung infections dominated by the opportunistically pathogenic bacterium Pseudomonas aeruginosa. During chronic CF lung infections, a single clone of P. aeruginosa can persist for decades and dominate end-stage CF lung disease due to its propensity to adaptively evolve to the respiratory environment, a process termed "pathoadaptation". Chronic rhinosinusitis (CRS), chronic inflammation and infection of the sinonasal space, is highly prevalent in CF and the sinuses may serve as the first site in the respiratory tract to become colonized by bacteria that then proceed to seed lung infections. We identified three evolutionary genetic routes by which P. aeruginosa evolves in the sinuses of people with CF, including through the evolution of mutator lineages and proliferative insertion sequences and culminating in early genomic signatures of host-restriction. Our findings raise the question of whether a significant portion of the pathoadaptive phenotypes previously thought to have evolved in response to selective pressures in the CF lungs may have first arisen in the sinuses and underscore the link between sinonasal and lung disease in CF. Graphical abstract and highlightsO_LIPseudomonas aeruginosa undergoes adaptive evolution in the sinuses of people with CF C_LIO_LIOver time, pathoadapted strains display early signatures of genome degradation consistent with recent host restriction C_LIO_LIMutations previously thought to occur in CF lungs may have first evolved in sinuses C_LI O_FIG O_LINKSMALLFIG WIDTH=200 HEIGHT=200 SRC="FIGDIR/small/359844v1_ufig1.gif" ALT="Figure 1"> View larger version (50K): org.highwire.dtl.DTLVardef@13b36aborg.highwire.dtl.DTLVardef@8230e1org.highwire.dtl.DTLVardef@1570c3eorg.highwire.dtl.DTLVardef@1e4e530_HPS_FORMAT_FIGEXP M_FIG C_FIG

microbiology