A yellowish-pink-coloured bacterial strain, TAPY14T, was isolated from a freshwater creek in Taiwan. Phylogenetic analyses based on 16S rRNA gene sequences showed that strain TAPY14T belonged to the genus Flavobacterium and showed the highest similarity (97.3 %) with respect to Flavobacterium reichenbachii WB 3.2-61T, Flavobacterium ginsengisoli DCY54T and Flavobacterium defluvii EMB117T and less than 97 % with other members of the genus. Cells of strain TAPY14T were Gram-stain-negative, strictly aerobic, motile by gliding and rod-shaped. Optimal growth occurred at 20-30 °C, pH 6 and in the presence of 0.5 % NaCl. Strain TAPY14T contained iso-C15 : 0 and summed feature 3 (C16 : 1ω6c and/or C16 : 1ω7c) as the predominant fatty acids. The polar lipid profile consisted of phosphatidylethanolamine, four uncharacterized aminophospholipids, one uncharacterized phospholipid and one uncharacterized lipid. The major polyamine was homospermidine. The major isoprenoid quinone was MK-6. The DNA G+C content of the genomic DNA was 38.1 mol%. The DNA-DNA hybridization values for strain TAPY14T with F. reichenbachii DSM 21791T, F. ginsengisoli JCM 17336T and F. defluvii DSM 17963T were less than 30 %. On the basis of the phylogenetic inference and phenotypic data, strain TAPY14T should be classified as a novel species, for which the name Flavobacterium fluviatile sp. nov. is proposed. The type strain is TAPY14T (=BCRC 81012T=LMG 29733T=KCTC 52446T).
Keywords: Bacteroidetes; Flavobacteriaceae; Flavobacterium fluviatile; freshwater creek; new taxa; polyphasic taxonomy.