Psychrobacter Oceani Sp Nov., Isolated From Marine Sediment

A novel marine bacterium, designated strain 4k5(T), was isolated from a sediment sample of the Pacific Ocean. The strain was Gram-stain-negative, strictly aerobic, non-motile, oxidase-positive and catalase-positive and required Na+ for growth. Its major isoprenoid quinone was ubiquinone 8(Q-8), and its cellular fatty acid profile consisted mainly of C(18:1)v9c (71.4 %), C-16:1 v7c (9.1 %) and C-18:0. The DNA G+C content was 45.3 mol%. 16S rRNA gene sequence analysis suggested that strain 4k5(T) is a member of the genus Psychrobacter. Strain 4k5T exhibited the closely phylogenetic affinity to Psychrobacter pacificensis IFO 16270(T) (99.4% 16S rRNA gene sequence similarity), P. piscatorii T-3-2(T) (97.7%), P. nivimaris 8812-7(T) (97.7%), P. celer SW-238(T) (97.7%), P. aestuarii SC35(T) (97.6%) and P. vallis CMS39(T) (97.6%). DNA DNA hybridization between strain 4k5(T) and P. pacificensis NBRC 103191(T), P. piscatorii JCM 15603(T). P. nivimaris DSM 16093(T), P. celer JCM 12601(T), P. aestuarii JCM 16343(T) and P. vallis DSM 15337(T) was 42.5, 47.0, 38.1, 23.7, 9.0 and 27.4%, respectively. Owing to the significant differences in phenotypic and chemotaxonomic characteristics, phylogenetic analysis based on the 16S rRNA gene sequence and DNA DNA relatedness data, the isolate merits classification within a novel species, for which the name Psychrobacter oceani sp. nov. is proposed. The type strain is 4k5T (=JCM 30235(T)=NCIMB 14948(T)).