Winogradskyella psychrotolerans sp. nov., a marine bacterium of the family Flavobacteriaceae isolated from Arctic sediment

Abstract

A novel Gram-negative, rod–coccus shaped, non-motile, strain, RS-3T, was isolated from a sediment sample collected from the marine transect of Kongsfjorden, Ny-Ålesund, Svalbard, Arctic. Colonies and broth cultures were yellowish in colour due to the presence of carotenoids. Strain RS-3T was positive for oxidase, aesculinase, caseinase, gelatinase and urease activities and negative for amylase, catalase, lipase, lysine decarboxylase, ornithine decarboxylase, DNase and β-galactosidase activities. The predominant fatty acids were iso-C15 : 0 (18.0), anteiso-C15 : 0 (16.8), iso-C15 : 1 G (14.2), anteiso-C15 : 1 A (6.0) and iso-C15 : 0 3-OH (6.8). Strain RS-3T contained MK-6 (72.42 %) and MK-7 (27.58 %) as the major respiratory quinones and phosphatidylethanolamine, two unidentified aminolipids and two unidentified lipids make up the polar lipid composition. The DNA G+C content of strain RS-3T was 34.7±1.2 mol%. The 16S rRNA gene sequence analysis indicated that Winogradskyella pacifica and Winogradskyella thalassocola are the most closely related species with sequence similarities to the type strains of these species of 98.5 and 97.7 %, respectively. However, DNA–DNA hybridization with Winogradskyella pacifica KCTC 22997T and Winogradskyella thalassocola DSM 15363T showed a relatedness of 22 and 42.5 % with respect to strain RS-3T. Based on the DNA–DNA hybridization values, phenotypic and chemotaxonomic characteristics and phylogenetic inference, strain RS-3T is proposed as a novel species of the genus Winogradskyella , for which the name Winogradskyella psychrotolerans sp. nov. is proposed. The type strain of Winogradskyella psychrotolerans sp. nov. is RS-3T ( = CIP 110154T = NBRC 106169T). An emended description of the genus Winogradskyella is provided.