Patiriisocius marinistellae gen. nov., sp. nov., isolated from the starfish Patiria pectinifera, and reclassification of Ulvibacter marinus as a member of the genus Patiriisocius comb. nov.

A marine strain, designated KK4 ^T , was isolated from the surface of a starfish, Patiria pectinifera , which was collected from seawater off the coast of Hokkaido, Japan. Strain KK4 ^T is a Gram-stain-negative, non-spore-forming, rod-shaped, aerobic bacterium that forms yellow-pigmented colonies. A phylogenetic relationship analysis, based on 16S rRNA gene sequences, revealed that strain KK4 ^T was closely related to Ulvibacter marinus IMCC12008 ^T , Ulvibacter antarcticus IMCC3101 ^T and Ulvibacter litoralis KMM 3912 ^T , with similarities of 96.9, 95.8 and 95.6 %, respectively, but low sequence similarities (<94 %) among other genera in the family Flavobacteriaceae . Genomic similarities between strain KK4 ^T and the three Ulvibacter type strains based on average nucleotide identity and digital DNA-DNA hybridization values were lower than the species delineation thresholds. Moreover, phylogenetic tree based on genome sequences showed that strain KK4 ^T was clustered with U. marinus IMCC12008 ^T and formed a branch independent from the cluster including type species of the genera Ulvibacter , Marixanthomonas , Marinirhabdus , Aureitalea and Aequorivita . Amino acid identity values between strain KK4 ^T / U. marinus IMCC12008 ^T and the neighbour type species/strains were 61.9-68.2% and 61.5-67.4 %, which were lower than the genus delineation threshold, implying the novel genus status of strain KK4 ^T . Strain KK4 ^T growth occurred at pH 6.0-9.0, 4-30 °C and in NaCl concentrations of 0.5-5.0 %, and optimally at pH 7.0, 25 °C and 3.0 %, respectively. Unlike Ulvibacter strains, strain KK4 ^T could assimilate glucose, mannose, galactose and acetate. The major quinone and fatty acids were menaquinone-6 and iso-C _15 : 0 (27.5 %), iso-C _15 : 1 G (22.5 %) and iso-C _17 : 0 3-OH (12.8 %), respectively. Based on genetic, phylogenetic and phenotypic properties, strain KK4 ^T represents a novel species of the genus Patiriisocius , for which the name Patiriisocius marinistellae gen. nov., sp. nov. is proposed. The type strain is KK4 ^T (=JCM 33344 ^T =KCTC 72225 ^T ). In addition, based on the current data, Ulvibacter marinus should be reclassified as Patiriisocius marinus comb. nov.