Pseudoprevotella muciniphila gen. nov., sp. nov., a mucin-degrading bacterium attached to the bovine rumen epithelium

A Gram-negative, strictly anaerobic mucin-degrading bacterium, which we designated strain E39(T), was isolated from the rumen epithelium of Korean cattle. The cells were non-motile and had a coccus morphology. Growth of strain E39(T) was observed at 30-45 degrees C (optimum, 39 degrees C), pH 6.5-8.5 (optimum, pH 7.5), and in the presence of 0.0-1.0% (w/v) NaCl (optimum, 0.0-0.5%). Strain E39(T) contained C-16:0, C-18:0, C-18:1 omega 9c, iso-C-15:0, and anteiso-C-15:0 as the major fatty acids. The major polar lipids were phosphatidylethanolamine, unidentified aminophospholipid, and unidentified lipids. The major respiratory isoprenoid quinones were MK-8 and MK-9. The major fermented end-products of mucin were acetate and succinate. The G+C content of the genomic DNA was 46.4 mol%. Strain E39(T) was most closely related to Alloprevotella rava 81/4-12(T) with an 87.3% 16S rRNA gene sequence similarity. On the basis of phenotypic, chemotaxonomic, and molecular properties, strain E39(T) represents a novel genus of the family Prevotellaceae; as such, the name Pseudoprevotella muciniphila gen. nov., sp. nov. is proposed. A functional annotation of the whole genome sequences of P. muciniphila E39(T) revealed that this bacterium has a putative mucin-degrading pathway and biosynthetic pathways of extracellular polymeric substances and virulence factors which enable bacteria to adhere to the epithelial cells and avoid the host's immune responses.

Automated summary

This study isolated a novel Gram-negative bacterium Pseudoprevotella muciniphila with mucin-degrading capabilities from the rumen epithelium of Korean cattle. The bacterium showed specific growth conditions and contained unique fatty acids, polar lipids, and respiratory quinones. Functional annotation of the genome revealed potential virulence factors that allow the bacterium to adhere to host cells and evade immune responses.