Flavobacterium alvei sp nov., isolated from a freshwater river

A yellow-pigmented, Gram-stain-negative, strictly aerobic, catalase-negative and oxidase-positive bacterium, designated strain HR-AY(T), was isolated from a water sample of the Han River. Cells were non-motile rods without flagella. Growth was observed at 5-30 degrees C (optimum, 20 degrees C), pH 5-9 (optimum, pH 7) and 0 % NaCl. The major respiratory quinone was menaquinone-6. Strain HR-AY(T) did not produce flexirubin-type pigments. The major fatty acids were summed feature 3 (comprising C-16( : 1 omega 7c) and/or C-16( : 1 omega 6c)), anteiso-C-15( : 0), iso-C-15( : 0) and C-16( : 0). The polar lipids comprised phosphatidylethanolamine and an unidentified phosphoamino lipid as major polar lipids, and four unidentified lipids were also detected as minor lipids. The DNA G+C content of strain HR-AY(T) was 34.4 mol%. Phylogenetic analysis based on 16S rRNA gene sequences revealed that strain HR-AY(T) belonged to the family Flavobacteriaceae in the phylum Bacteroidetes, and formed a phylogenic lineage with members of the genus Flavobacterium. The 16S rRNA gene sequence similarity showed that strain HR-AY(T) was most closely related to Flavobacterium chungbukense CS100(T) (97.91 %) and Flavobacterium glaciei 0499(T) (97.74 %). Based on these results, strain HR-AY(T) represents a novel species of the genus Flavobacterium, for which the name Flavobacterium alvei sp. nov. is proposed. The type strain is HR-AY(T) (=KACC 19407(T)=JCM 32264(T)).