Flavisericum labens gen. nov., sp. nov., a novel member of the family Flavobacteriaceae isolated from the seawater of Dongshan Bay.

A Gram-negative, aerobic, non-motile and rod-shaped bacterial strain, designated DST062, was isolated from the seawater of Dongshan Bay in Fujian, China. Growth occurred with 0.5-6% (w/v) NaCl (optimum, 3%), at 4-40 °C (optimum, 28 °C) and at pH 7.0-8.0 (optimum, 7.0), displaying positive reactions for both catalase and oxidase activities. Comparative 16S rRNA gene sequence studies showed that strain DST062 formed a distinct lineage within the family Flavobacteriaceae. It exhibited the highest 16S rRNA gene sequence similarity value to Confluentibacter sediminis DSL-48 (95.35%). This low similarity value enabled clear differentiation of strain DST062 from strains of related genera such as Confluentibacter, Snuella, Jejuia, and Tamlana through 16S rRNA gene sequence analysis. The G + C content of the genomic DNA was 35.92%. The estimated Average Nucleotide Identity and digital DNA-DNA Hybridization values between strain DST062 and the reference species ranged from 73.7 to 76.0% and from 18.5 to 20.0%, respectively. The major fatty acid profile comprised iso-C, summed feature 3 (Cω6c/Cω7c), iso-C G and iso-C 3-OH. The respiratory quinone was identified as menaquinone 6. The major polar lipids of strain DST062 included two aminolipids phosphatidylethanolamine, and two unknown polar lipids. Based on phylogenetic, chemotaxonomic and genomic analysis, strain DST062 represents a novel species from a novel genus of the family Flavobacteriaceae, for which the name Flavisericum labens gen. nov. sp. nov. is proposed. The type strain is DST062 (= MCCC 1K08936 = KCTC 102361).