牛源隐孢子虫分离株的分子鉴定

Molecular identification of cow-derived Cryptosporidium isolates

目的对安徽4个牛源隐孢子虫分离株进行鉴定,旨在阐明感染牛隐孢子虫主要虫种。方法采用PCR和Nested-PCR方法分别对4个分离株18S rRNA、HSP70基因进行扩增和测序,所测定的序列经生物信息学分析它们同源性和构建种系发育进化树,以确定各分离株与其他隐孢子虫虫种之间的亲缘关系。结果 (1)它们的18S rRNA基因和HSP70基因与安氏隐孢子虫(C.andersoni)AY954887相似性可达88.3%和98.3%;(2)在遗传进化树方面,它们与AY954892(河南株)亲缘关系接近。结论此次分离的4个牛源隐孢子虫分离株均为安氏隐孢子虫(Cryptosporidium andersoni)。

Objective To idertify 4 isolates of cow-derived Cryptosporidium and clarify the main species that cause the infection.Method Four Cryptosporidium isolates were identified.PCR and Nest-PCR were applied to amplify the target genes of 18S rRNA,HSP70 from four dairy farm;their products were sequenced,and the analysis of homology and establishment of their phylogeny tree were made.Result The homology in 18S rRNA and HSP70 were 88.3% and 98.3% between the four Cryptosporidium isolates and C.andersoni（AY954887）;they were close to AY954892（Henan isolates） in phylogeny.Conclusion The four isolates can be identified as C.andersoni.