Nocardiopsis valliformis sp. nov., an alkaliphilic actinomycete isolated from alkali lake soil in China

Abstract

A strain (HBUM 20028(T)) isolated from alkali lake soil in China was studied by a polyphasic taxonomic approach. The strain produced abundant aerial and substrate mycelia. Long spore chains were borne on the aerial mycelium, and the substrate mycelium was often arranged in a shape like a fence or palisade. The special characteristic of strain HBUM 20028(T) was its abundant growth under alkaline conditions, at pH 8.0-14.0. The cell wall of strain HBUM 20028(T) contained meso-diaminopimelic acid but no diagnostic sugar. Major phospholipids included diphosphatidylglycerol and phosphatidylcholine. The major menaquinones were MK-10(H(2)), MK-10(H(4)) and MK-10(H(6)). The major cellular fatty acids were iso-C(16 : 0) (31.66 %), anteiso-C(17 : 0) (14.85 %) and C(18 : 1)omega9c (14.73 %). All of these characters consistently indicated that strain HBUM 20028(T) belongs to the genus Nocardiopsis. DNA-DNA hybridization between the strain and type strains of related species gave relatedness values far below 70 %. Based on 16S rRNA gene sequence analysis, DNA relatedness and phenotypic characteristics, a novel species with the name Nocardiopsis valliformis sp. nov. is proposed. The type strain is HBUM 20028(T) (=DSM 45023(T) =CGMCC 4.2135(T)).