Nocardiopsis terrae sp. nov., a halophilic actinomycete isolated from saline soil

A Gram-positive, moderately halophilic, facultatively alkaliphilic, catalase- and oxidase-positive, obligately aerobic, filamentous actinomycete strain, designated YIM 90022T, was isolated from saline soil collected from the Qaidam Basin, north-west China. Phylogenetic analysis based on 16S rRNA gene sequences indicated that the new isolate was a member of the genus Nocardiopsis and the sequence similarities between the isolate and the type strains of members of the genus Nocardiopsis were in the range of 95.1–98.7%. Phenotypic and chemotaxonomic properties of this organism also indicated that strain YIM 90022T was a member of the genus Nocardiopsis. The strain grew well on most of the media tested, producing yellow-white to deep brown substrate mycelium and white aerial mycelium. Light gray to deep brown diffusible pigments were produced. The substrate mycelium was well developed and fragmented with age; the aerial mycelium produced long, straight to flexuous spore chains with non-motile, smooth-surfaced, rod-shaped spores on them. The strain grew in the presence of 1–15% (w/v) total salts (optimum, 3–5%) and at pH 6.0–10.5 (optimum, pH 8.5) and 10–45°C (optimum, 30°C). Whole-cell hydrolysates of strain YIM 90022T contained meso-diaminopimelic acid and no diagnostic sugars. The predominant menaquinones were MK-10(H4), MK-9(H8), MK-10(H6) and MK-10(H8). Polar lipids comprised diphosphatidylglycerol, phosphatidylcholine, phosphatidylglycerol and phosphatidylmethylethanolamine. The major cellular fatty acids were iso-C16:0, anteiso-C17:0, 10-methyl-C18:0 and 10-methyl-C17:0. The DNA G + C content of strain YIM 90022T was 71.5 mol%. The combination of phylogenetic analysis, DNA–DNA relatedness data, phenotypic characteristics and chemotaxonomic data supported the suggestion that strain YIM 90022T represents a new species of the genus Nocardiopsis, for which the name Nocardiopsis terrae sp. nov. is proposed. The type strain is YIM 90022T (=CCTCC AA 208011T =KCTC 19431T).