Molecular characterization and phylogenetic analysis of Clostridium perfringens from animals and their environments by cpn60 UT sequencing analysis

Clostridium perfringens an ubiquitous environmental bacterium causes major food borne illnesses, digestive diseases and several soft tissue infections in humans and animals. In the present study, toxin typing of 91 C. perfringens isolates from animals with enteric diseases and their environments revealed the presence of type A and C strains. Enterotoxin gene (cpe), responsible for majority of the food poisoning incidences in humans and enteric infections in animals was present in 60.43 % of the isolates of which 76.3 % and 23. 36 % were chromosomal and plasmid borne respectively. Neighbour-joining tree inferred from cpn60 UT nucleotide sequences could differentiate the cpe+ve isolates from the cpe−ve isolates, provide clear distinction between the cpe-IS1470 and cpe-IS1151 genotypes and segregate type A and C strains in separate clusters. The present study is the first report on the utilization of cpn60 UT region for C. perfringens phylogeny analysis and demonstrates that cpn60 UT analysis alone, to a greater extent can be a simple, rapid and efficient method for differentiating between cpe+ve and cpe−ve strains or toxin types. The cpb2 gene was observed among 30 isolates of which 16.6 % were from porcine sources while the rest were of non-porcine and environmental origin. The cpb2 sequences obtained in the present study though similar among them were diverse both from the consensus and atypical cpb2 sequences reported globally and formed a separate cluster. The study thus reports of novel cpb2 gene variant and warrants its characterization through further studies.