Ferruginibacter alkalilentus gen. nov., sp. nov. and Ferruginibacter lapsinanis sp. nov., novel members of the family 'Chitinophagaceae' in the phylum Bacteroidetes, isolated from freshwater sediment

Six Gram-negative, non-gliding, rod-shaped bacterial strains isolated from freshwater sediment were subjected to polyphasic analyses to determine their taxonomic positions. Analysis of the 16S rRNA gene sequences of the six strains revealed that they represent two separate genomic species in a new lineage within the phylum Bacteroidetes, related to members of the family 'Chitinophagaceae', in which they were most closely related to members of the genus Terrimonas (93.4-90.5 %). Two of the isolates, HU1-GD23(T) and HU1-HG42(T), had a sequence similarity of 96.2 %, with DNA G+C contents of 39.4 and 38.5 mol%, respectively. They possessed MK-7 as the predominant respiratory quinone and contained high amounts of iso-pentadecanoic acid and 3-hydroxy-iso-heptadecanoic acid in their cell envelopes, properties shared by members of the family 'Chitinophagaceae'. They were well differentiated from other members of the family 'Chitinophagaceae' by additional physiological and biochemical characteristics. In conclusion, strains HU1-GD23(T) (=KCTC 22306(T)=LMG 24312(T)) and HU1-HG42(T) (=KCTC 22305(T)=LMG 24324(T)) are considered to represent two novel species of a novel genus, Ferruginibacter gen. nov., for which the names Ferruginibacter alkalilentus sp. nov. and Ferruginibacter lapsinanis sp. nov., are proposed, respectively.