Flavobacterium aquidurense sp nov and Flavobacterium hercynium sp nov., from a hard-water creek

Ten new Flavobacterium-like strains were isolated from freshwater of the hard-water creek Westerhofer Bach, northern Germany. These strains formed two phylogenetic groups: strains WB 1.1-56(T), WB 1.1 -04, WB 1.1 -14, WB 1.1 -57 and WB 1.1 -63; and strains WB 4.2-33(T), WB 4.1-86, WB 4.2-34, WB 4.2-32 and WB 4.2-78. Cells were Gram-negative, yellow-pigmented, chemoheterotrophic rods. Their major fatty acid profiles were similar, consisting of iso-C-15: 0, iso-C-15:0 3-OH, iso-C-17.0 3-OH and summed feature 3 (C-16: 1 omega 7c and/or iso-C-15:0 2-OH). DNA G + C contents for strains WB 1.1-56(T) and WB 4.2-33(T) were 33.5 and 37.5 mol%, respectively. Phylogenetic analysis based on almost complete 16S rRNA gene sequences indicated that strain WB 1.1 -56(T) was phylogenetically most closely related to Flavobacterium frigidimaris KUC-1(T), and that strain WB 4.2-33(T) was related most closely to F frigidimaris KUC-1(T) and Flavobacterium saccharophilum DSM 1811(T). Levels of 16S rRNA gene sequence similarity between strains WB 1.1-56 T and WB 4.2-33 T and the type strains of recognized members of the genus Flavobacterium were below 98%. DNA-DNA hybridization experiments confirmed the separate genomic status of strains WB 1.1-56(T) and WB 4.2-33(T). Strains WB 1.1-56(T) and WB 4.2-33(T) and their respective relatives differed from phylogenetically related Flavobacterium species based on several phenotypic characteristics. On the basis of their phenotypic and phylogenetic; distinctiveness, the two groups of strains are considered to represent two novel species, for which the names Flavobacterium aquidurense sp. nov, (type strain WB 1.1-56(T) =DSM 18293(T)=ClP 109242(T)) and Flavobacterium hercynium sp. nov. (type strain WB 4.2-33(T) =DSM 18292(T)=ClP 10924 1(T)) are proposed.