Identification of a Clostridium cocleatum strain involved in an anti-Clostridium difficile barrier effect and determination of its mucin-degrading enzymes.

We isolated Gram-positive circular bacterium HB1 from intestinal microflora showing resistance to colonization by Clostridium difficile in mice (Su et. al., 1986a,b). We studied its enzymatic capacity to degrade mucin the first potential barrier to implantation of strains in the intestine. Its biochemical characteristics, terminal metabolites and the electrophoretic profiles of proteins and DNA-DNA homology indicated that it was a strain of Clostridium cocleatum. This strain displayed numerous glucosidase activities which were assumed to play a role in the degradation of mucin oligosaccharide chains in the digestive tract. These enzymes included alpha- and beta-galactosidases, beta-glucosidase, beta-N-acetylglucosaminidase, sialidase and alpha-N-acetylgalactosaminidase.