Flavobacterium quisquiliarum sp. nov., isolated from activated sludge.

A Gram-staining-negative, aerobic, rod-shaped bacterium, EA-12, was isolated from activated sludge in Fujian Province, PR China. The results of phylogenetic analysis of the 16S rRNA gene sequences indicated that it was closely related to Flavobacterium pectinovorum DSM 6368 (97.5 %), Flavobacterium banpakuense 15F3 (97.0 %) and Flavobacterium arsenitoxidans S2-3H (96.9 %). Cells grew at 15-37 °C (optimum, 25 °C), at pH 5.0-9.0 (optimum, pH 7.0) and in the presence of 0-1.0 % (w/v) NaCl. The strain contained MK-6 as the major menaquinone and the major cellular fatty acids were iso-C15 : 0, summed feature 3 (C16 : 1ω6c and/or C16 : 1ω7c) and C16 : 0 3-OH. The polar lipids consisted of phosphatidylethanolamine and one unidentified phospholipid. The DNA G+C content was 36.1 mol% (Tm). The DNA-DNA relatedness between strain EA-12 and F. pectinovorum DSM 6368 was 38.6 %. On the basis of phenotypic, chemotaxonomic and phylogenetic comparisons with relatives and DNA-DNA relatedness values, it is concluded that EA-12 represents a novel species within the genus Flavobacterium, for which the name Flavobacterium quisquiliarum sp. nov. is proposed. The type strain is EA-12 (=CGMCC 1.15345=NBRC 111769).