Pseudonocardia benzenivorans sp nov.

A Gram-positive, rod-shaped, non-spore-forming bacterium (B5(T)) was isolated from an enrichment culture that contained 1,2,3,5-tetrachlorobenzene as the sole source of carbon. On the basis of 16S rRNA gene sequence similarity studies, strain B5(T) was shown to belong to the family Pseudonocardiaceae and was related most closely to Pseudonocardia sulfidoxydans (98.8%) and Pseudonocardia hydrocarbon oxydans (98.3%). 16S rRNA gene sequence similarity to other Pseudonocardia species was <97%. Chemotaxonomic data [major menaquinone, MK-8(H-4); major polar lipids, diphosphatidylglycerol, phosphatidylethanolamine and phosphatidylinositol; major fatty acids, C-16:0, iso-C-16:0 and iso-C-15:0] supported the affiliation of strain B5(T) to the genus Pseudonocardia. The results of DNA-DNA hybridizations and physiological and biochemical tests allowed genotypic and phenotypic differentiation of strain B5(T) from P. sulfidoxydans and P., hydrocarbon oxydans. Strain B5(T) therefore represents a novel species of the genus Pseudonocardia, for which the name Pseudonocardia benzenivorans sp. nov. is proposed, with the type strain B5(T) (=DSM 44703(T)=CIP 107928(T)).