Exiguobacterium soli sp. nov., a psychrophilic bacterium from the McMurdo Dry Valleys, Antarctica

Abstract

A novel psychrophilic bacterium, designated strain DVS 3Y^T, was isolated from a moraine sample from the McMurdo Dry Valleys, Antarctica. Phenotypic and chemotaxonomic characteristics and data from a phylogenetic analysis based on 16S rRNA gene sequences indicated that strain DVS 3Y^T was related to the genus Exiguobacterium. Strain DVS 3Y^T exhibited >97% gene sequence similarity with respect to Exiguobacterium acetylicum DSM 20416^T (97.4%), Exiguobacterium oxidotolerans DSM 17272^T (97.4%), Exiguobacterium indicum IAM 15368^T (97.6%), Exiguobacterium undae DSM 14481^T (98.2%), Exiguobacterium sibiricum DSM 17290^T (98.6%) and Exiguobacterium antarcticum DSM 14480^T (99.6%). However, the levels of DNA-DNA relatedness between strain DVS 3Y^T and E. acetylicum DSM 20416^T, E. oxidotolerans JCM 12280^T, E. indicum IAM 15368T, E. undae DSM 14481^T, E. sibiricum DSM 17290^T and E. antarcticum DSM 14480^T were less than 70% (52, 25, 16, 33, 16 and 38?%, respectively). Strain DVS 3Y^T also differed from these six closely related species in a number of phenotypic traits. Phenotypic, chemotaxonomic and phylogenetic data suggest that strain DVS 3Y^T represents a novel species of the genus Exiguobacterium, for which the name Exiguobacterium soli sp. nov. is proposed. The type strain is DVS 3Y^T (=MTCC 4816^T=JCM 14376^T).