genomics
Research Article | Host-Microbe BiologySpecies Designations Belie Phenotypic and Genotypic Heterogeneity in Oral StreptococciRepresentative type strains are commonly used to characterize bacterial species, yet species are phenotypically and genotypically heterogeneous. Conclusions about strain physiology and activity based on a single strain therefore may be inappropriate and misleading. When selecting strains for probiotic use, the assumption that all strains within a species share the same desired probiotic characteristics may result in selection of a...
Research Article | Ecological and Evolutionary ScienceUsing Core Genome Alignments To Assign Bacterial SpeciesWith the increasing availability of genome sequences, we sought to develop and apply a robust, portable, and high-resolution method for the assignment of genera and species designations that can recapitulate classically defined taxonomic designations. Using cutoffs derived from the lengths and sequence identities of core genome alignments along with phylogenetic analyses, we sought to evaluate or reevaluate genus- and species-level...
Special Issue Perspective | Ecological and Evolutionary ScienceSeven Billion Microcosms: Evolution within Human MicrobiomesRational microbiome-based therapies may one day treat a wide range of diseases and promote wellness. Yet, we are still limited in our abilities to employ such therapies and to predict which bacterial strains have the potential to stably colonize a person.
Research Article | Ecological and Evolutionary ScienceSignatures of Selection at Drug Resistance Loci in Mycobacterium tuberculosisMycobacterium tuberculosis, the causative agent of tuberculosis (TB), is a significant burden on global health. Antibiotic treatment imposes strong selective pressure on M. tuberculosis populations. Identifying the mutations that cause drug resistance in...
Research Article | Novel Systems Biology TechniquesMagic Pools: Parallel Assessment of Transposon Delivery Vectors in BacteriaMolecular genetics is indispensable for interrogating the physiology of bacteria. However, the development of a functional genetic system for any given bacterium can be time-consuming. Here, we present a streamlined approach for identifying an effective transposon mutagenesis system for a new bacterium. Our strategy first involves the construction of hundreds of different transposon vector variants, which we term a “magic pool.” The...
Research Article | Ecological and Evolutionary ScienceParallel Evolution of Group B Streptococcus Hypervirulent Clonal Complex 17 Unveils New Pathoadaptive MutationsThe incidence of group B Streptococcus (GBS) neonatal disease continues to be a significant cause of concern worldwide. Strains belonging to clonal complex 17 (CC17) are the most frequently responsible for GBS infections in neonates, especially among late-onset disease cases. Therefore, we undertook the largest genomic study of GBS CC17 strains to date to decipher the genetic bases of their remarkable colonization and infection...
Research Article | Applied and Environmental ScienceNon-Toxin-Producing Bacillus cereus Strains Belonging to the B. anthracis Clade Isolated from the International Space StationThe International Space Station Microbial Observatory (Microbial Tracking-1) study is generating a microbial census of the space station’s surfaces and atmosphere by using advanced molecular microbial community analysis techniques supported by traditional culture-based methods and modern bioinformatic computational modeling. This approach will lead to long-term, multigenerational studies of microbial population dynamics in a closed...
Research Article | Molecular Biology and PhysiologyCombining Genome-Scale Experimental and Computational Methods To Identify Essential Genes in Rhodobacter sphaeroidesKnowledge about the role of genes under a particular growth condition is required for a holistic understanding of a bacterial cell and has implications for health, agriculture, and biotechnology. We developed the Tn-seq analysis software (TSAS) package to provide a flexible and statistically rigorous workflow for the high-throughput analysis of insertion mutant libraries, advanced the knowledge of gene essentiality in...
Resource Report | Host-Microbe BiologyListeriomics: an Interactive Web Platform for Systems Biology of ListeriaIn the last decades, Listeria has become a key model organism for the study of host-pathogen interactions, noncoding RNA regulation, and bacterial adaptation to stress. To study these mechanisms, several genomics, transcriptomics, and proteomics data sets have been produced. We have developed Listeriomics, an interactive web platform to browse and correlate these heterogeneous sources of information. Our website will allow...
Editor's Pick Research Article | Ecological and Evolutionary ScienceComparative Genome Analyses of Vibrio anguillarum Strains Reveal a Link with Pathogenicity TraitsComparative genome analysis of strains of a pathogenic bacterial species can be a powerful tool to discover acquisition of mobile genetic elements related to virulence. Here, we compared 28 V. anguillarum strains that differed in virulence in fish larval models. By pan-genome analyses, we found that six of nine highly virulent strains had a unique core and accessory genome. In contrast, V. anguillarum strains that were...