Nocardioides daedukensis sp. nov., a halotolerant bacterium isolated from soil

Abstract

A Gram-positive, non-motile and rod- or coccoid-shaped bacterial strain, MDN22T, was isolated from a soil sample from Korea. Strain MDN22 T grew optimally at pH 7.0-8.0, at 30 °C and in the presence of 0-0.5% (w/v) NaCl. Phylogenetic analyses based on 16S rRNA gene sequences showed that strain MDN22T was phylogenetically most closely related to the genera Nocardioides and Marmoricola. In the neighbour-joining phylogenetic tree, strain MDN22T was most closely related to Nocardioides jensenii KCTC 9134T, with which it exhibited 98.3% 16S rRNA gene sequence similarity. The strain exhibited 93.1-96.9% and 95.3-95.9% 16S rRNA gene sequence similarities to the type strains of other species of the genera Nocardioides and Marmoricola, respectively. The chemotaxonomic properties of strain MDN22T were consistent with those of the genus Nocardioides; the cell-wall peptidoglycan type was based on LL-2,6-diaminopimelic acid, the predominant menaquinone was MK-8(H4) and the major fatty acids were iso-C 16 : 0 and C17 : 1. The DNA G+C content was 68.7 mol%. DNA-DNA relatedness data and differential phenotypic properties suggested that strain MDN22T could be differentiated from N. jensenii and Nocardioides dubius. On the basis of the data obtained, strain MDN22T is considered to represent a novel species of the genus Nocardioides, for which the name Nocardioides daedukensis sp. nov., is proposed. The type strain is MDN22T (5KCTC 19601T=CCUG 57505T).