南京市食源性致泻大肠埃希氏菌多位点序列分型及耐药基因分析  

Sequence type and resistance genes of Escherichia coli diarrhea isolates from foodborne disease surveillance,Nanjing

作　　者：王燕[1] 江晓[1] 叶艳华[1] 王璇[1] 董潇潇[1] 许文炯[1] 雍玮[1] 杜雪飞[1] 丁洁 WANG Yan;JIANG Xiao;YE Yan-hua;WANG Xuan;DONG Xiao-xiao;XU Wen-jiong;YONG Wei;DU Xue-fei;DING Jie(Nanjing Center for Disease Control and Prevention,Nanjing,Jiangsu 210003,China)

机构地区：[1]南京市疾病预防控制中心,江苏南京210003

出　　处：《现代预防医学》2020年第15期2810-2813,2823,共5页Modern Preventive Medicine

基　　金：江苏预防医学项目(Y2018003)。

摘　　要：目的对南京地区食源性疾病监测中致泻性大肠埃希氏菌(diarrheagenic Escherichia coli,DEC)分离株进行多位点序列分型(Multilocus Sequence Typing,MLST),了解超广谱β-内酰胺酶(Extended-spectrum beta-lactamases,ESBLs)耐药基因blaTEM、blaCTX-M和质粒介导的喹诺酮耐药基因(plasmid-mediated quinolone resistance,PMQR)qnrA、qnrB、qnrS、oqxA、oqxB、qepA、aac(6’)-Ib-cr的流行情况及其与MLST型别之间的关联。方法对食源性监测中60株DEC分离株的管家基因(adk、fumC、gyrB、icd、mdh、purA、recA)进行PCR扩增和测序,用EnteroBase上下载的ST(Sequencetype)分型方案确定菌株序列型。PCR法检测超广谱β-内酰胺酶ESBLs耐药基因和质粒介导的喹诺酮耐药基因PMQR。结果60株DEC可分为34个ST型别,其中ST48为优势型别(16.67%),发现两个新等位基因型,fumC1413和purA746,一个新序列型ST9953。共有43株(71.67%)携带ESBLs耐药基因,10株(16.67%)携带喹诺酮耐药基因PMQR。ESBLs阳性的大肠埃希氏菌株中占比最高的是ST10组群。结论南京地区食源性疾病监测中致泻性大肠埃希氏菌最常见的序列型是ST48。特定的ST型别在DEC不同类型中的分布不同,两者之间呈现一定相关性。ESBLs广泛流行,blaTEM为主要流行基因,最流行的PMQR基因是qnrS。Objective To investigate sequence types and the prevalence of ESBLs resistant genes and PMQR genes of DEC isolates obtained from Foodborne Disease Surveillance in Nanjing,so as to understand the possible link between sequence types and the resistant genes.Methods PCR amplification for housekeeping genes(adk,fumC,gyrB,icd,mdh,purA,recA),and then to obtain the sequence types of 60 strains of DEC by downloading ST scheme in EnteroBase.PCR method was used to detect ESBLs resistance gene and PMQR genes.Results 60 strains of DEC were divided into 34 ST types,and ST48 prevailed over other types(16.67%).Two new alleles,fumC1413 and purA746,and a new sequence type ST9953 were identified.Forty-three isolates were identified with ESBLs resistance genes,and the positive rate was 71.67%.Ten strains carried PMQR genes,and the positive rate was 16.67%.ST10 group accounted for the highest percentage in ESBLs positive strains.Conclusion The most common ST type of DEC strains in food-borne disease in Nanjing is ST48.The distribution of STs varied among different DEC types.ESBLs is widely disseminated,among which blaTEM is the most frequent gene,and the most frequent gene of PMQR is qnrS.

关 键 词：大肠埃希氏菌 多位点序列分型 序列型 耐药基因 

分 类 号：R446.5[医药卫生—诊断学]