Oceanicola nitratireducens sp. nov., a marine alphaproteobacterium isolated from the South China Sea.

A Gram-negative, non-motile, short-rod-shaped bacterial strain (JLT1210(T)) that accumulates poly-beta-hydroxybutyrate granules was isolated from the Beibu Gulf in the South China Sea. Cells have polar or subpolar flagella. Phylogenetic analyses based on 16S rRNA gene sequences showed that the strain belongs to the genus Oceanicola in the order Rhodobacterales, class Alphaproteobacteria. The closest neighbours were Oceanicola nanhaiensis SS011B1-20(T) (96.5 % similarity) and Oceanicola batsensis HTCC2597(T) (96.4 %). The predominant respiratory ubiquinone of strain JLT1210(T) was Q-10 and the DNA G+C content was 72.8 mol%. Evidence from genotypic, chemotaxonomic and phenotypic data shows that strain JLT1210(T) represents a novel species of the genus Oceanicola, for which the name Oceanicola nitratireducens sp. nov. is proposed; the type strain is JLT1210(T) (=LMG 24663(T)=CGMCC 1.7292(T)).