Comparative genomic and metagenomic investigations of the Corynebacterium tuberculostearicum species complex reveals potential mechanisms underlying associations to skin health and disease

ABSTRACT Corynebacterium are a diverse genus and dominant member of the human skin microbiome. Recently, we reported that the most prevalent Corynebacterium species found on skin – including Corynebacterium tuberculostearicum and Corynebacterium kefirresidentii – comprise a narrow species complex despite the diversity of the genus. Here, we apply high-resolution phylogenomics and comparative genomics to describe the structure of the C. tuberculostearicum species complex. We find this species complex is missing a fatty acid biosynthesis gene family which is often found in multi-copy in approximately 99% of other Corynebacterium species. Conversely, this species complex is enriched for multiple genetic traits, including a gene encoding for a collagen-like peptide. Further, through metagenomic investigations, we find that one species within the complex, C. kefirresidentii , increases in relative abundance during atopic dermatitis flares and show that most members of this species possess a colocalized set of putative virulence genes.