A Gram-negative, facultatively anaerobic, slightly halophilic bacterium that was motile by gliding, designated KMM 6390^T, was isolated from the coastal green alga Ulva fenestrata collected from the Sea of Japan. A comparative analysis of 16S rRNA gene sequences revealed that strain KMM 6390^T was a member of the genus Winogradskyella , with Winogradskyella echinorum KMM 6211^T as its closest relative (97.8 % 16S rRNA gene sequence similarity). 16S rRNA gene sequence similarities between the isolate and other members of the genus Winogradskyella were 95.4–96.7 %. DNA–DNA relatedness between the isolate and W. echinorum KMM 6211^T was 27 %. Strain KMM 6390^T was able to grow with 0.5–4.0 % NaCl and at 4–37 °C. The isolate decomposed casein, gelatin, starch and DNA and produced acid from galactose, d-glucose, lactose and maltose. The major fatty acids were iso-C_15 : 0, iso-C_15 : 1, anteiso-C_15 : 0 and C_15 : 0. The polar lipid profile comprised phosphatidylethanolamine and two unknown aminolipids. The DNA G+C content was 34.2 mol%. On the basis of phylogenetic, chemotaxonomic and phenotypic investigations, strain KMM 6390^T represents a novel species of the genus Winogradskyella , for which the name Winogradskyella ulvae sp. nov. is proposed; the type strain is KMM 6390^T ( = KCTC 23626^T = LMG 26444^T). Emended descriptions of the genus Winogradskyella and of W. thalassocola , W. echinorum , W. exilis and W. eximia are also provided.

Previously unknown associations of Vibrio gigantis with the trepang Apostichopus japonicus and of V. pomeroyi with the sea urchin Strongylocentrotus nudus were described in Vostok Bay of Peter the Great Bay, Sea of Japan. Bacterial isolates were identified based on their morphological, cultural and biochemical characteristics, as well as by 16S rRNA gene sequencing. Strain 915 (V. gigantis) was found to possess amylase, gelatinase, chitinase, pustulanase, glucosidase, galactosidase, and alginase, while strain 929 (V. pomeroyi) possessed amylase, gelatinase, chitinase, and fucoidanase. S. nudus and A. japonicus probably provide favorable niches for V. gigantis and V. pomeroyi and act as natural reservoirs for these bacteria in Peter the Great Bay. The broad spectrum of enzymes in associated vibrios suggests their role in food digestion of the above marine invertebrates.