Flavobacterium fulvum sp. nov., Flavobacterium pedocola sp. nov. and Flavobacterium humicola sp. nov., three new members of the family Flavobacteriaceae, isolated from soil.

Abstract

Four Gram-stain-negative, non-endospore-forming, non-motile strains were found in soil, South Korea. Based on their 16S rRNA gene sequences, strains UCM-R15T and UCM-R21 are most closely related to Flavobacterium enshiense DK69T (97.4-97.5 %, pairwise similarity) while strains UCM-R36T and UCM-46T are most closely related to Flavobacterium suncheonense GH29-5T (97.5 % and 98.3 %, respectively), with all four strains sharing less than 97 % pairwise similarity to the type strain of any other species of the genus Flavobacterium. None of the four strains can reduce/digest nitrate or urea. The only menaquinone detected was MK-6 and the major fatty acids were iso-C15 : 0, iso-C17 : 0 3-OH, iso-C15 : 1 G and summed feature 9 in all the type strains. Phosphatidylethanolamine was found in three strains as the major polar lipid, phosphatidylserine was found in both strains UCM-R15T and UCM-R36T, but not UCM-46T, and phosphatidylmonomethylethanolamine only occurred in strain UCM-R15T. The genomic DNA G+C content values of strains UCM-R15T, UCM-R21, UCM-R36T and UCM-46T were 35.3-39.0 mol%. Taking into account their physiological and biochemical characteristics, we suggest that three of the strains are novel members of the genus Flavobacterium. We propose the names Flavobacterium fulvum sp. nov. for type strain UCM-R15T (=KACC 18666T=NBRC 111764T), and strain UCM-R21 as an additional strain Flavobacterium pedocola sp. nov. for type strain UCM-R36T (=KACC 18668T=NBRC 111765T), and Flavobacterium humicola sp. nov. for type strain UCM-46T (=KACC 18575T=NBRC 111657T).