Isolation and Characterization of a Mucin-Degrading Bacterium Attached to the Rumen Epithelium of Korean Cattle

Abstract

This study was performed to isolate mucin degrading bacteria attached to rumen epithelial cells. Microbial diluent was prepared by extensive homogenization of rumen epithelial cells of the ventral sacs of Korean cattle steers, and it was inoculated with a liquid medium containing a mucin as a sole carbon source in anaerobic condition. Enriched bacterial culture was serially diluted and spread on a mucin agar medium. Single colonies were picked and cultured in the same liquid mucin medium.

A novel bacterium, designated strain E39T, was isolated and its 16S rRNA gene was sequenced. Phylogenetic analyses based on 16S rRNA gene sequences showed that strain E39T was most closely related to Alloprevotella rava with an 87.3% sequence similarity. Strain E39T is Gram-negative, strictly anaerobic, and non-motile coccus. Growth of strain E39T was observed at 30–45°C (optimum, 39°C), at pH 6.5 and 8.5 (optimum, 7.5), and in the presence of 0.0–1.0% (w/v) NaCl (optimum, 0.0–0.5%). The G+C content of genomic DNA was 46.2 mol%. Enzyme profiles were identified with the Rapid ID 32A identification kit (bioMe´rieux), and this species had was arginine dihydrolase, α-galactosidase, β-galactosidase, glutamic acid decarboxylase, α-fucosidase, alkaline phosphatase, leucyl glycine arylamidase, alanine arylamidase, and glutamyl glutamic acid arylamidase activity. On the basis of the phenotypic, chemotaxonomic, and physiological properties, strain E39T represents a novel genus of the family Prevotellaceae

the name Psuedoprevotella muciniphila gen. nov., sp. nov. is proposed

the type strain is E39T (= KCTC 15717T= JCM 32621T).