Flavobacterium longum sp. nov. and Flavobacterium urocaniciphilum sp. nov., isolated from a wastewater treatment plant, and emended descriptions of Flavobacterium caeni and Flavobacterium terrigena.

Two Gram-staining-negative, strictly aerobic, non-endospore-forming, non-motile, rod-shaped bacteria, designated strains YIT 12745T and YIT 12746T, were isolated from sludge from a wastewater treatment plant. 16S rRNA gene sequence analyses indicated that these strains belonged to the genus Flavobacterium. In these analyses, strains YIT 12745T and YIT 12746T were most closely related to the type strains of Flavobacterium caeni and Flavobacterium terrigena, with 16S rRNA gene sequence similarity values of 94.9% and 96.2%, respectively. For both novel strains, menaquinone (MK-6) was the only respiratory quinone. The major fatty acids of strain YIT 12745T were iso-C15:1 G (14.4%), iso-C16:0 (13.2%), C15:0 (12.9%), iso-C15:0 (12.9%) and iso-C17:0 3-OH (11.5%). Those of strain YIT 12746T were iso-C15:0 (21.5%), iso-C16:0 (13.3%), C15:0 (12.0%) and iso-C15:1 G (11.9%). The genomic DNA G+C contents of strains YIT 12745T and YIT 12746T were 48.7 and 30.9 mol%, respectively. From their differential phenotypic and phylogenetic characteristics, these strains are considered to represent two novel species of the genus Flavobacterium, for which the names Flavobacterium longum sp. nov. (type strain YIT 12745T=JCM 19141T=DSM 27077T) and Flavobacterium urocaniciphilum sp. nov. (type strain YIT 12746T=JCM 19142T=DSM 27078T) are proposed. Emended descriptions of Flavobacterium caeni and Flavobacterium terrigena are also proposed.