Molecular detection of the ruminal bacterium, Butyrivibrio fibrisolvens, in feces from rural residents of southern India

Abstract

Objective: This study was undertaken to determine whether Butyrivibrio fibrisolvens, a butyrate-producing bacterium present in the rumen of cattle, could be detected in the feces of healthy southern Indians. Subjects and methods: Feces were collected from 25 children and 25 adults from a village and from 25 children living in a town in southern India. Four cow dung samples were also collected from the village. DNA was extracted and real-time PCR was carried out using primers targeted at 16S rDNA sequences peculiar to B. fibrisolvens. Amplicons were subjected to temporal temperature gradient electrophoresis (TTGE) and DNA sequencing. Phylogenetic analysis was done. Results: B. fibrisolvens rDNA was detected in feces of 13 adults (52%) and 15 children (60%) from the village, but not in urban children. In TTGE, amplicons from children and from cattle migrated as a single band, with only one sample showing a second band. Sequencing revealed 12 novel sequences (accessed in GenBank, 8 from children, 4 from dung) closely similar to the ATCC strain of B. fibrisolvens. Conclusions: B. fibrisolvens, a microorganism found in cattle, colonizes the human gastrointestinal tract in rural southern India.