Nocardioides aquiterrae sp nov., isolated from groundwater in Korea

A bacterial strain, GW-9(T), which was isolated from groundwater in Korea, was subjected to a polyphasic taxonomic study using phenotypic characterization and phylogenetic and genetic methods. Phylogenetic analysis based on 16S rDNA sequences showed that strain GW-9(T) forms an evolutionary lineage within the radiation enclosing Nocardioides species and, in particular, a coherent cluster with Nocardioides pyridinolyticus. The cell-wall peptidoglycan type of strain GW-9(T) was based on LL-diaminopimelic acid as the diamino acid, indicating wall chemotype I. The predominant menaquinone was MK-8(H-4). Strain GW-9(T) had a cellular fatty acid profile containing straight-chain, branched, unsaturated and 10-methyl fatty acids. The major fatty acid was iSO-C-16:0. The DNA G + C content of strain GW-9(T) was 73 mol%. The 16S rDNA of strain GW-9(T) was 99.2% similar to that of the type strain of Nocardioides pyridinolyticus and 94.9-96.0% similar to sequences of the type strains of other Nocardioides species. Differences in phenotypic characteristics and genetic distinctiveness indicate that strain GW-9(T) is separate from previously described Nocardioides species. Therefore, on the basis of the data presented, a novel species of the genus Nocardioides, Nocardioides aquiterrae sp. nov., is proposed. The type strain is strain GW-9(T) (= KCCM 41647(T)= JCM 11813(T)).