摘要
目的明确国内分离的45株尿道致病性大肠埃希菌(UPEC)P菌毛的papG和papA的基因型分布状况及两者可能的组合形式,为国内UPEC菌株的致病机制、遗传变异、流行病学分析和免疫防治等研究提供基础依据。方法应用papG和papA多重PCR基因分型方法对45株UPEC菌株进行papG和papA基因分型,并分析基因型分布与组合形式。结果45株UPECP菌毛的papG均为Ⅱ型,与国外报道显著不同。其中44株(97.8%)papA基因可成功分型,1株(UPEC4030,2.2%)不能分型,提示为未知基因型。44株papA基因分型结果阳性菌株中,11个基因型分布如下:24株(54.55%)具有单一型;13株(29.55%)具有2个基因型;4株(9.09%)和3株(6.82%)分别具有3个和4个基因型。单一基因型较为常见的为F7-2(25.00%)、F11(6.82%)和F16(9.09%)。受试菌株各种基因型出现的频次,优势基因型依次为F10和F13各12株(27.27%)、F7-2和F11各11株(25.00%)、F14为10株(22.27%)、F16为9株(20.45%)。具有2个以上基因型的组合形式与国外不同,并首次发现了4个基因型(F8+F9+F13+F14)组合的UPEC菌株。结论国内分离的45株UPEC菌株papG高度保守,而papA呈现高度多态性,并出现与国外不同的基因型。
Objective To define the genotypic distribution and combination forms of papG and papA of 45 uropatho- gertic Escherichia coli（UPEC） strains isolated in China, and to lay a foundation of further study on pathogenesis, genetic variation, epidemiological analysis as well as immunotherapy. Methods The papA and papG genes of 45 UPEC stains were typed by the multiplex PCR assay and the genotypic distribution and combination forms of the two genes were analysed. Re- suits Among the 45 strains, all the strains carded class I1 genotypes of papG（44,97.8% ） were found by the multiplex pa- pA PCR assay（F-PCR） to containing one or more of 11 known papA alleles （F-types）. Only one strain （UPEC4030） was negative according to F-PCR assay and by PCR. Hence,it was suspected of harboring novel variant of papA. Of the F-PCR positive strains,24（54. 55% ）had a single F types, 13 （29. 55% ）had two types,4（9.09% ） and 3 （6. 82% ） had three and four types. F7-2（25.00% ）, F11 （6. 82% ） and F16 （9.09%） tended to occur alone. Among the 11 known F types, nine F types occurred at least once in the population in decreasing order of prevalence as follows：F10 and F13 （27.27%）, F＇/-2 and Fl1（25.00% ） ,F14（22.27% ） ,F16（20. 45% ）. The combination forms with more than 2 papA genotypes were different from those found abroad. The strains containing four F types（ F8 ,F9 ,F13 and F14） were found for the first time. Conclusion The results suggested that the papG sequences of UPEC strains isolated in China were highly conservative and the papA sequences possessed polymorphisms. The 45 UPEC strains isolated had different papA genotypes from those found outside China and their clinical and epidemiological meaning need further study.
出处
《中国公共卫生》
CAS
CSCD
北大核心
2009年第6期724-726,共3页
Chinese Journal of Public Health
基金
卫生部科研基金项目(WKJ2006-2-10)
