江苏省肠出血性大肠埃希菌O157的基因PCR-RFLP分型研究

目的对历年从江苏省不同地区分离的肠出血性大肠埃希菌O157（以下简称：O157）进行分型分析。方法采用多聚酶链反应-限制性片段长度多态性分析（PCR-RFLP）方法对108株O157分子分型,比较不同地区、不同年份菌型差异。结果根据EcoRV限制性酶切图谱可将菌株分成JS01-JS10十个不同的型别。主要菌型JS01占64.9%,JS02型与JS01型菌株酶切图谱相似度很高,JS03和JS04型菌株数目较少（12株）,但近一半属于人源菌株。从时间方面看,1999年分离的菌型最多;从地区方面看,铜山县分离到的菌株型别最为多样化。结论不同菌型之间的致病性存在差异,菌株与地理来源的关系密切。PCR-RFLP方法操作简便、重复性好,为O157的流行病学研究提供了一条全新途径。

Molecular typing of Escherichia coli O157 isolated in Jiangsu Province with PCR-RFLP

The aim of the study to analyze the homology of E.coli O157 strains from several regions of Jiangsu province in these years.Polymerase Chain Reaction-restriction fragment length polymorphism（PCR-RFLP） was used for the molecular subtyping of one hundred and eight E.coli O157 strains,which showed distributional diversity in different areas and years.EcoRV restriction patterns were divided into ten types named JS01-JS10.There was 64.9% of all the E.coli O157 belonged to JS01,which was very similar to JS02 in digest pattern.Almost half of 12 strains named JS03 and JS04 were isolated from human samples.Most of the EcoRV restriction patterns were observed in 1999,whereas strains from Tongshan had great variety.The strains tested were mainly grouped according to cultivars origins,while pathogenicity differed in restriction patterns.From the above observations,it is evident that PCR-RFLP is easy and repeatable,providing a brand-new method for epidemiological research of E.coli O157.