Pseudonocardia nantongensis sp. nov., a novel endophytic actinomycete isolated from the coastal halophyte Tamarix chinensis Lour

Abstract

A novel isolate, designated strain KLBMP 1282(T) was isolated from the surface-sterilized leaves of a coastal halophyte Tamarix chinensis Lour., collected from Nantong, Jiangsu Province, east of China. Phylogenetic analysis based on 16S rRNA gene sequences revealed that this strain belongs to the genus Pseudonocardia, being most closely related to Pseudonocardia kongjuensis LM 157(T) (98.33%), Pseudonocardia autotrophica IMSNU 20050(T) (97.77%), Pseudonocardia endophytica YIM 56035(T) (97.63%), Pseudonocardia ammonioxydans H9 (T) (97.62%) and Pseudonocardia compacta IMSNU 20111(T) (97.56 %); similarity to other type strains of the genus Pseudonocardia was <97.5%. Chemotaxonomic data confirmed the affiliation of strain KLBMP 1282(T) to the genus Pseudonocardia. Strain KLBMP 1282(T) contained MK-8(H(4)) as the predominant ubiquinone and iso-C(16:0) as the major fatty acid. The polar lipids detected in strain KLBMP 1282(T) were diphosphatidylglycerol, phosphatidylglycerol, phosphatidylcholine, phosphatidylmethylethanolamine, phosphatidylethanolamine, phosphatidylinositol, phosphatidylinositol mannosides, one unknown phospholipid and four unknown glycolipids. The DNA G+C content of strain KLBMP 1282(T) was 73.1mol%. The results of DNA-DNA hybridizations and the phylogenetic analysis, together with the phenotypic and biochemical tests, allowed the differentiation of strain KLBMP 1282(T) from strains of other recognized Pseudonocardia species. Therefore, strain KLBMP 1282(T) represents a novel species of the genus Pseudonocardia, for which the name Pseudonocardia nantongensis sp. nov. is proposed. The type strain is KLBMP 1282(T) (=KCTC 29053(T)=NBRC 108677(T)).