Psychrobacter celer sp. nov., isolated from sea water of the South Sea in Korea

A Gram-negative, non-motile, non-spore-forming, slightly halophilic bacterial strain, SW-238(T), was isolated from sea water collected from the South Sea in Korea, and subjected to a polyphasic taxonomic study. The organism grew optimally at 25-30 degrees C and in the presence of 2-3% (w/v) NaCl. Strain SW-238(T) was characterized chemotaxonomically as containing ubiquinone (Q-8) as the predominant respiratory lipoquinone and C(18:1)omega9c as the major fatty acid. Its DNA G+C content was 47.6 mol%. Phylogenetic analyses based on 16S rRNA gene sequences showed that strain SW-238(T) fell within the radiation of the cluster comprising Psychrobacter species. The 16S rRNA gene sequence of strain SW-238(T) had similarity levels of 94.8-97.9% to sequences of the type strains of recognized Psychrobacter species. Levels of DNA-DNA relatedness between strain SW-238(T) and the type strains of 10 phylogenetically related Psychrobacter species were below 70%. On the basis of phenotypic and phylogenetic data and genetic distinctiveness, strain SW-238(T) (=KCTC 12313(T)=JCM 12601(T)) was placed in the genus Psychrobacter as the type strain of a novel species, for which the name Psychrobacter celer sp. nov. is proposed.