Naturally Occurring Clostridium perfringens Nontoxic Alpha-Toxin Variant as a Potential Vaccine Candidate against Alpha-Toxin-Associated Diseases

Clostridium perfringens mutant strain 121A/91 shows neither enzymatic (phospholipase C) nor hemolytic activity. Nevertheless, the cpa gene and the corresponding alpha-toxin variant are detectable. Vaccination with this genetically constructed alpha-toxin variant, rAT121/91, induces antibodies capable of significantly reducing activities induced by wild-type toxin. Thus, rAT121/91 could be a useful vaccine candidate.