Bacteroides chinchillae sp. nov. and Bacteroides rodentium sp. nov., isolated from chinchilla (Chinchilla lanigera) faeces

Abstract

Gram-negative anaerobic rods were isolated from chinchilla (Chinchilla lanigera) faeces and three strains, ST170T, ST180 and ST28T, were investigated taxonomically. On the basis of phylogenetic analyses and specific phenotypic characteristics, the three strains belonged to the genus Bacteroides. Phylogenetic analysis of their 16S rRNA gene sequences revealed that strains ST170T and ST180 formed a single cluster and a distinct line of descent. Strain ST170T exhibited 99.7 % 16S rRNA gene sequence similarity with strain ST180 and 95.1, 94.6 and 94.4 % 16S rRNA gene sequence similarity with Bacteroides massiliensis JCM 13223T, Bacteroides dorei JCM 13471T and Bacteroides vulgatus JCM 5826T, respectively. Strain ST28T also formed a distinct line of descent and exhibited the highest 16S rRNA gene sequence similarity with Bacteroides uniformis JCM 5828T (98.1 %). Low DNA–DNA relatedness (1 %) between strain ST28T and B. uniformis JCM 5828T clearly indicated that they belonged to different species. Analysis of hsp60 sequences also supported these relationships. The DNA G+C contents of strains ST170T and ST28T were 45.2 and 41.0 mol%, respectively. On the basis of phenotypic characteristics and phylogenetic data, two novel species, Bacteroides chinchillae sp. nov. (type strain ST170T  = JCM 16497T  = CCUG 59335T) and Bacteroides rodentium sp. nov. (type strain ST28T  = JCM 16496T  = CCUG 59334T), are proposed.