Microbial community analysis of rectal methanogens and sulfate reducing bacteria in two non-human primate species

Background: Methanogenesis by methanogenic Archaea and sulfate reduction by sulfate reducing bacteria (SRB) are the major hydrogenotrophic pathways in the human colon. Methanogenic status of mammals is suggested to be under evolutionary rather than dietary control. However, information is lacking regarding the dynamics of hydrogenotrophic microbial communities among different primate species. Methods: Rectal swabs were collected from 10 sooty mangabeys (Cercocebus atys) and 10 baboons (Papio hamadryas). The diversity and abundance of methanogens and SRB were examined using PCR-denaturing gradient gel electrophoresis (DGGE) and real-time quantitative PCR (qPCR). Results: The DGGE results revealed that intestinal Archaea and SRB communities differ between mangabeys and baboons. Phylogenetic analyses of Archaea DGGE bands revealed two distinct clusters with one representing a putative novel order of methanogenic Archaea. The qPCR detected a similar abundance of methanogens and SRB. Conclusions: Intestinal Archaea and SRB coexist in these primates, and the community patterns are host species-specific.