hsp60 and 16S rRNA gene sequence relationships among species of the genus Bacteroides with the finding that Bacteroides suis and Bacteroides tectus are heterotypic synonyms of Bacteroides pyogenes

Abstract

hsp60gene sequences were determined for members of the genusBacteroidesand sequence similarities were compared with those obtained for the 16S rRNA gene. Among the 29Bacteroidestype strains, the mean sequence similarity of thehsp60gene (84.5 %) was significantly less than that of the 16S rRNA gene (90.7 %), indicating a high discriminatory power of thehsp60gene. Species of the genusBacteroideswere differentiated well byhsp60gene sequence analysis, except forBacteroides pyogenesJCM 6294T,Bacteroides suisJCM 6292TandBacteroides tectusJCM 10003T. Thehsp60gene sequence analysis and the levels of DNA–DNA relatedness observed demonstrated that these three type strains are a single species. Consequently,B. suisandB. tectusare heterotypic synonyms ofB. pyogenes. This study suggests that thehsp60gene is an alternative phylogenetic marker for the classification of species of the genusBacteroides.