While metagenomics can provide insight into microbial community metabolic potential, understanding factors that influence gene abundance is necessary to maximize the information gained from this analysis. Gene abundances are influenced by chemical or physical conditions along with other factors, such as copy number variation between taxa, methodological biases, or issues associated with identification and classification. Here,...

Summary The number, size and severity of aquatic low‐oxygen dead zones are increasing worldwide. Microbial processes in low‐oxygen environments have important ecosystem‐level consequences, such as denitrification, greenhouse gas production and acidification. To identify key microbial processes occurring in low‐oxygen bottom waters of the Chesapeake Bay, we sequenced both 16S rRNA genes and shotgun metagenomic libraries to dete...

Summary Although animal‐associated microbial communities (microbiomes) are increasingly recognized to influence health, the extent to which animals represent highly selective habitats for microbes leading to predominance of high host specificity remains poorly understood. Here, we show that vibrios, which are well‐known commensals and opportunistic pathogens of marine animals, overall display little host preference, likely bec...

Summary The O‐antigen is a highly diverse structure expressed on the outer surface of Gram‐negative bacteria. The products responsible for O‐antigen synthesis are encoded in the wbe region, which exhibits extensive genetic diversity. While heterogeneous O‐antigens are observed within Vibrio species, characterization of these structures has been devoted almost exclusively to pathogens. Here, we investigate O‐antigen diversity a...