Flavobacterium flaviflagrans sp. nov., a bacterium of the family Flavobacteriaceae isolated from forest soil

Two strains of bacteria designated CB-3T and CB-31 were isolated from Kyonggi University forest soil. Cells were aerobic, Gram-stain-negative, oxidase-positive, non-motile, non-spore-forming, rod-shaped and yellow-pigmented. They were able to grow at 15-42 °C, pH 5.5-9.5 and with 0-1.5 % (w/v) NaCl concentration. Flexirubin-type pigments were absent. Phylogenetic analysis based on 16S rRNA gene sequences revealed that strains CB-3T and CB-31 formed a lineage within the family Flavobacteriaceae of the phylum Bacteroidetes that was distinct from various species of the genus Flavobacterium, including Flavobacterium humicola UCM-46T (99.58 % sequence similarity), Flavobacterium suncheonense GH29-5T (98.12 %), Flavobacterium pedocola UCM-R36T (97.57 %), Flavobacterium fulvum UCM-R15T (96.8 %) and Flavobacterium cauense R2A-7T (96.31 %). Both strains contained MK-6 as the sole quinone. The major polar lipid was phosphatidylethanolamine. The major cellular fatty acids were iso-C15 : 0, iso-C17 : 0 3-OH, iso-C15 : 0 3-OH, summed feature 9 (iso-C17 : 1ω9c and/or C16 : 0 10-methyl) and iso-C15 : 1 G. The DNA G+C content of the strains was 35.8-36.7 mol%. DNA-DNA relatedness between strain CB-3T and the most closely related members of the genus Flavobacterium ranged from 32 % to 59 %. The morphological, physiological, chemotaxonomic and phylogenetic analyses clearly distinguished strains CB-3T and CB-31 from their closest phylogenetic neighbours. Thus, strains CB-3T and CB-31 represent a novel species of the genus Flavobacterium, for which the name Flavobacterium flaviflagrans sp. nov. is proposed. The type strain is CB-3T (=KEMB 9005-535T=KACC 19112T=NBRC 112704T).