Nocardioides hankookensis sp. nov., isolated from soil

Abstract

A Gram-positive, non-motile, rod-shaped bacterial strain, DS-30T, was isolated from soil from Dokdo, Korea, and its taxonomic position was investigated by means of a polyphasic study. Strain DS-30T grew optimally at pH 6.0-7.0 and 25 °C in the presence of 0-0.5% (w/v) NaCl. A phylogenetic analysis based on 16S rRNA gene sequences showed that strain DS-30T fell within the genus Nocardioides, forming a coherent cluster with the type strains of Nocardioides aquiterrae and Nocardioides pyridinolyticus, with which it exhibited 16S rRNA gene sequence similarity values of 98.1 and 98.3%, respectively. Strain DS-30T exhibited 16S rRNA gene sequence similarity values below 96.8% with respect to the type strains of the other Nocardioides species. The chemotaxonomic properties of strain DS-30T were consistent with those of the genus Nocardioides: the cell-wall peptidoglycan type was based on LL-diaminopimelic acid, the predominant menaquinone was MK-8(H4) and the major fatty acids were iso-C16:0, C17:1ω8c and C18:1ω9c. The DNA G + C content was 71.3 mol%. Strain DS-30T exhibited DNA-DNA relatedness levels of 19 and 22% with respect to the type strains of N. aquiterrae and N. pyridinolyticus, respectively, and could be differentiated from these species with reference to a number of phenotypic characteristics. On the basis of the data obtained, strain DS-30T represents a novel species of the genus Nocardioides, for which the name Nocardioides hankookensis sp. nov. is proposed. The type strain is DS-30T (=KCTC 19246T =CCUG 54522T).