Metabolic capabilities are highly conserved among human nasal-associated <i>Corynebacterium</i> species in pangenomic analyses

Pangenomic analysis with estimation of functional capabilities facilitates our understanding of the full biologic diversity of bacterial species. We performed systematic genomic, phylogenomic, and pangenomic analyses with qualitative estimation of the metabolic capabilities of four common human nasal <i>Corynebacterium</i> species, along with focused experimental validations, generating a foundational resource. The prevalence of each species in human nasal microbiota is consistent with the common coexistence of at least two species. We identified a notably high level of metabolic conservation within and among species indicating limited options for species to occupy distinct metabolic niches, highlighting the importance of investigating interactions among nasal <i>Corynebacterium</i> species. Comparing strains from two continents, <i>C. pseudodiphtheriticum</i> had restricted geographic strain distribution characterized by an evolutionarily recent loss of assimilatory sulfate reduction in U.S. strains. Our findings contribute to understanding the functions of <i>Corynebacterium</i> within human nasal microbiota and to evaluating their potential for future use as biotherapeutics.