Flavobacterium dispersum sp. nov., isolated from a freshwater spring.

A novel bacterial strain MVW-23 was isolated from a freshwater spring in Taiwan. The strain was Gram-staining-negative, strictly aerobic, motile by gliding, rod-shaped and formed translucent yellow colonies. Optimal growth occurred at 20-30 °C, pH 7.0, and in the presence of 0.5-1 % NaCl. Phylogenetic analyses based on 16S rRNA gene sequences showed that strain MVW-23 belonged to the genus Flavobacterium and showed the highest levels of sequence similarity with respect to Flavobacterium denitrificans ED5 (97.3 %), Flavobacterium kyungheense THG-107 (97.2 %) and Flavobacterium defluvii EMB117 (97.0 %). Strain MVW-23 contained iso-C15 : 0, summed feature 3 (C16 : 1ω6c and/or C16 : 1ω7c) and iso-C17 : 0 3-OH as the predominant fatty acids. The polar lipid profile consisted of phosphatidylethanolamine, three uncharacterized aminophospholipids and one uncharacterized phospholipid. The major polyamine was homospermidine. The major isoprenoid quinone was MK-6. The DNA G+C content of the genomic DNA was 39.9 mol%. The DNA-DNA hybridization value for strain MVW-23 with F. denitrificans DSM 15936, F. kyungheense LMG 26575 and F. defluvii DSM 17963 was less than 35 %. Differential phenotypic properties, together with the phylogenetic inference, demonstrate that strain MVW-23 should be classified as a novel species of the genus Flavobacterium, for which the name Flavobacterium dispersum sp. nov. is presented. The type strain is MVW-23 (=BCRC 80978=LMG 29558=KCTC 52234).