Multiple-locus variable-number tandem repeat analysis for strain typing of Clostridium perfringens

Clostridium perfringens is ubiquitous in the environment and causes diseases in man and animals, with syndromes ranging from enteritis, enterotoxemia, and sudden death to food poisoning and gas gangrene. Understanding the epidemiology of these infections and of the evolution of virulence in C. perfringens necessitate an efficient, time and cost effective strain typing method. Multiple-locus variable-number tandem repeat analysis (MLVA) has been applied to typing of other pathogens and we describe here the development of a MLVA scheme for C. perfringens. We characterized five variable tandem repeat (VNTR) loci, four of which are contained within protein encoding genes and screened 112 C. perfringens isolates to evaluate typability, reproducibility, and discriminatory power of the scheme. All the isolates were assigned a MLVA genotype and the technique has excellent reproducibility, with a numerical index of discrimination for the five VNTR loci of 0.995. Thus MLVA is an efficient tool for C. perfringens strain typing, and being PCR based makes it rapid, easy, and cost effective. In addition, it can be employed in epidemiological, ecological, and evolutionary investigations of the organism.