Filobacterium Rodentium Gen. Nov., Sp Nov., A Member Of Filobacteriaceae Fam. Nov Within The Phylum Bacteroidetes; Includes A Microaerobic Filamentous Bacterium Isolated From Specimens From Diseased Rodent Respiratory Tracts

Strain SMR-C-T, which was originally isolated from rats as the SMR strain, had been named 'cilia-associated respiratory bacillus' ('CAR bacillus'). 'CAR bacillus' was a Gram-stain-negative, filamentous argentophilic bacterium without flagella. SMR-C-T grew at 37 degrees C under microaerobic conditions, showed gliding activity, hydrolysed urea and induced chronic respiratory diseases in rodents. The dominant cellular fatty acids detected were iso-C-15:0 and anteiso-C-15:0. The DNA G+C content was 47.7 mol%. 16S rRNA gene sequence analysis revealed SMR-C-T and other strains of 'CAR bacillus' isolated from rodents all belonged to the phylum Bacteroidetes. The nearest known type strain, with 86 % 16S rRNA gene sequence similarity, was Chitinophaga pinensis DSM 2588(T) in the family Chitinophagaceae. Strain SMR-C-T and closely related strains of 'CAR bacillus' rodent-isolates formed a novel family-level Glade in the phylum Bacteroidetes with high bootstrap support (98-100 %). Based on these results, we propose a novel family, Filobacteriaceae fam. nov., in the order Sphingobacteriales as well as a novel genus and species, Filobacterium rodentium gen. nov., sp. nov., for strain SMR-C-T. The type strain is SMR-C-T (=JCM 19453T=DSM 100392(T)).