粪样中产气荚膜梭菌的分离及cpe^+菌株的鉴定

Identification of cpe^+ Clostridium perfringens isolated from feces

目的分离粪样中的产气荚膜梭菌基因分型。方法按照国标方法从粪样中分离产气荚膜梭菌,应用PCR进行毒素基因型分型和鉴定。结果从1 411份粪样中分离到557株产气荚膜梭菌,其中553个为A型,其余为C型。1株人源分离株携带cpe基因,该cpe的ORF与标准菌株在核苷酸和氨基酸水平上的同源性分别为99.9%和100%,而且该基因位于染色体上。结论初步摸清了我国粪样中产气荚膜梭菌的动态分布,并在人粪样品中发现了cpe+产气荚膜梭菌,为分子流行病学研究提供了重要理论依据。

In this study,1 411 fecal samples were collected from people,pigs,goats and cattle,and 557 C.perfringens were isolated from these samples.These isolates were further identified by biochemical test and genotyped by multiplex PCR.Among these 557 isolates,533 were type A C.perfringens and all the others were type C.Of the 14.4% isolates harbored β2 gene,and only one isolated from human source carried cpe gene.The ORF sequences of cpe of the isolate were determined,and the result showed that the cpe ORF consisted of 960 bp,which shared 99.9% of sequence identity and 100% of amino acid sequence identity with those of the reference strains NCTC8239.This cpe＋ isolate was further determined for cpe location by multiplex,and the result showed that the isolate harbored the chromosomal cpe.In conclusion,dynamic distribution of C.perfringens in China has been found out preliminary,and one isolate from human source carried cpe gene,thus providing an important theoretical basis for the molecular epidemiology of related research.