Nocardioides koreensis sp. nov., Nocardioides bigeumensis sp. nov. and Nocardioides agariphilus sp. nov., isolated from soil from Bigeum Island, Korea

Abstract

Three Gram-positive, coccoid to rod-shaped actinobacteria, designated strains MSL-09T, MSL-19T and MSL-28T, were isolated from a soil sample collected from Bigeum Island in Korea, and were subjected to a polyphasic taxonomic analysis. All three isolates grew optimally at pH 7.5-9.0 and 28-30 °C. 16S rRNA gene analysis revealed that all three strains belonged to the genus Nocardioides, with strains MSL-09T, MSL-19T and MSL-28T respectively showing the highest sequence similarity to Nocardioides aquaticus DSM 11439T (96.25 %), Nocardioides aquiterrae GW-9T (95.75 %) and Nocardioides terrigena DS-17T (95.61 %). Chemotaxonomically, they contain LL-2,6-diaminopimelic acid in the cell-wall peptidoglycan, MK- 8(H4) as the predominant menaquinone and diphosphatidylglycerol, phosphatidylglycerol and some unknown lipids as the polar lipids found in the cell wall. iso-C16:0 is a major fatty acid. The G+C content of the DNA was respectively 69.9, 69.3 and 69.4 mol% for strains MSL-09T, MSL-19T and MSL-28T. Based on morphological, physiological, biochemical and chemotaxonomic characters presented in this study, the three strains represent novel species of the genus Nocardioides. The names Nocardioides koreensis sp. nov. (type strain MSL-09T =KCTC 19272T =DSM 19266T), Nocardioides bigeumensis sp. nov. (type strain MSL-19T =KCTC 19290T =DSM 19320T) and Nocardioides agariphilus sp. nov. (type strain MSL-28T =KCTC 19276T =DSM 19323T) are proposed.