Taxonomic characterization of nine strains isolated from clinical and environmental specimens, and proposal of Corynebacterium tuberculostearicum sp. nov.

Nine unidentified Gram-positive, lipophilic corynebacteria were isolated from clinical and food samples and subjected to a polyphasic taxonomic analysis. The bacteria were distinguished from Corynebacterium species with validly published names by biochemical tests, fatty acid content and whole-cell protein analysis. Comparative 16S rRNA gene sequence analysis demonstrated unambiguously that the nine strains were related phylogenetically to the species 'Corynebacterium tuberculostearicum' and represented a distinct subline within the genus Corynebacterium. On the basis of both phenotypic and phylogenetic evidence, the formal description of Corynebacterium tuberculostearicum sp. nov. is proposed. The type strain of C. tuberculostearicum is Medalle XT (=LDC-20T=CIP 107291T=CCUG 45418T=ATCC 35529T).