Nocardiopsis litoralis sp. nov., a halophilic marine actinomycete isolated from a sea anemone

Abstract

A Gram-positive, moderately halophilic, alkalitolerant, filamentous, aerobic actinomycete, designated strain JSM 073097(T), was isolated from a sea anemone collected from a tidal flat in the South China Sea. Phylogenetic analyses based on 16S rRNA gene sequences indicated that the new isolate was a member of the genus Nocardiopsis and was most closely related to Nocardiopsis kunsanensis HA-9(T), Nocardiopsis xinjiangensis YIM 90004(T) and Nocardiopsis salina YIM 90010(T) (99.6, 98.5 and 98.1 % similarity, respectively). Phenotypic characteristics and chemotaxonomic data also indicated that strain JSM 073097(T) was a member of the genus Nocardiopsis. The strain grew well on most of the media tested, producing white to yellow-white substrate mycelium and white aerial mycelium and straight to flexuous hyphae. 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. The strain grew in the presence of 1-15 % (w/v) total salts and at pH 6.0-10.5 and 20-35 degrees C; optimum growth occurred in the presence of 5-7 % (w/v) total salts and at pH 8.5 and 25 degrees C. Whole-cell hydrolysates of strain JSM 073097(T) contained meso-diaminopimelic acid and no diagnostic sugars. The predominant menaquinones were MK-10(H(4)), MK-10(H(6)) and MK-10(H(8)). The major cellular fatty acids were iso-C(15 : 0), iso-C(16 : 0), anteiso-C(16 : 0) and 10-methyl C(18 : 0). Polar lipids comprised diphosphatidylglycerol, phosphatidylcholine and phosphatidylglycerol. The DNA G+C content of strain JSM 073097(T) was 70.4 mol%. The combination of phylogenetic analysis, DNA-DNA relatedness data, phenotypic characteristics and chemotaxonomic data supported the suggestion that strain JSM 073097(T) represents a novel species of the genus Nocardiopsis, for which the name Nocardiopsis litoralis sp. nov. is proposed. The type strain is JSM 073097(T) (=DSM 45168(T)=KCTC 19473(T)).