Flavobacterium amnigenum sp. nov. Isolated from a River.

A yellowish, flexirubin-pigment-producing strain I3-3 T was isolated from river water in Iksan, the Republic of Korea. The strain was gram-negative, aerobic, non-motile, showed catalase and oxidase activities, and could grow at a temperature range of 10-35 degrees C, pH 5.0-10 and 0-2.0% (w/v) of NaCl. The major fatty acids were iso-C-15:0, iso-C-17:0 3-OH and summed feature 3 (comprising C-16:1 omega 7c and/or C-16:1 omega 6c). The isolate contained phosphatidylethanolamine, one aminolipid, and two unidentified lipids as the major polar lipids. Menaquinone-6 (MK6) was the major respiratory quinone. The G+C content of the genomic DNA of strain I3-3(T) was 35.6%. Comparison of the 16S rRNA gene sequence with the sequences of the closely related type strains showed highest sequence similarity of 96.95% and 96.93% to Flavobacterium nitrogenifigens NXU-44(T) and Flavobacterium compostarboris 15C3(T), respectively. Based on phenotypic and phylogenetic distinctiveness, strain I3-3(T) is considered as a member of novel species within the genus Flavobacterium, for which Flavobacterium amnigenum sp. nov. is proposed. The type strain is I3-3(T) (=KCTC 52884(T) =NBRC 112871(T)).