Flavobacterium soyangense sp nov., a psychrotolerant bacterium, isolated from an oligotrophic freshwater lake

A bacterial strain, designated IMCC26223(T), was isolated from an oligotrophic freshwater lake, Lake Soyang, Korea. Cells of strain IMCC26223(T) were Gram-staining negative, strictly aerobic, non-motile and short-rod-shaped. Growth occurred at pH 6-8 (optimum, pH 7.0), at 4-25 degrees C (optimum, 15 degrees C) and with 0-0.5% (w/v) NaCl (optimum, 0 %). Phylogenetic analyses based on 16S rRNA gene sequences showed that strain IMCC26223 T was identified as a member of the genus Flavobacterium and most closely related to Flavobacterium fluvii H7(T) (97.6 %), Flavobacterium segetis AT1048(T) (97.5 %) and Flavobacterium weaverense AT1042(T) (97.2 %). DNA-DNA relatedness between strain IMCC26223(T) and F. fluvii H7(T) was 41.5-51.7% in the reciprocal hybridization. Strain IMCC26223(T) contained MK-6 as the major respiratory quinone. The major cellular fatty acids consisted of C-16 : 0, iso-C-15 : 0, anteiso-C-15 : 0 and summed feature 3 (C-16 : 1 omega 6c and/or C-16 : 1 omega 7c), and the polar lipids were phosphatidylethanolamine, an unidentified aminolipid and two unidentified lipids. The DNA G+C content of strain IMCC26223(T) was 34.5 mol%. On the basis of 16S rRNA gene phylogeny and phenotypic characterization, strain IMCC26223(T) represents a novel species of the genus Flavobacterium, for which the name Flavobacterium soyangense sp. nov., is proposed. The type strain is IMCC26223(T) (=KCTC 52245(T)=JCM 31384(T)).