Pseudoalteromonas shioyasakiensis sp. nov., a marine polysaccharide-producing bacterium

A novel exopolysaccharide-producing bacterium, designated strain SE3 T , was isolated from Pacific Ocean sediment. The strain was Gram-stain-negative, motile, strictly aerobic, 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 mainly consisted of C 16 : 1 ω7 c , C 16 : 0 and C 18 : 1 ω7 c . The DNA G+C content was 46.9 mol%. 16S rRNA gene sequence analysis suggested that strain SE3 T is a member of the genus Pseudoalteromonas . Strain SE3 T exhibited close phylogenetic affinity to Pseudoalteromonas arabiensis JCM 17292 T (99.0 % 16S rRNA gene sequence similarity), Pseudoalteromonas lipolytica LMEB 39 T (98.39 %) and Pseudoalteromonas donghaensis HJ51 T (97.65 %). The DNA–DNA reassociation values between strain SE3 T and P. arabiensis JCM 17292 T , P. lipolytica JCM 15903 T and P. donghaensis LMG 24469 T were 31, 26 and 44 %, respectively. Owing to the significant differences in phenotypic and chemotaxonomic characteristics, phylogenetic analysis based on 16S rRNA gene sequences and DNA–DNA relatedness data, the new isolate merits classification as a representative of novel species, for which the name Pseudoalteromonas shioyasakiensis is proposed. The type strain is SE3 T ( = JCM 18891 T = NCIMB 14852 T ).