临床分离的革兰阴性菌3类整合酶基因的筛查与Ⅰ类整合子结构分析

Screening and structural analysis of integrase genes in gram-negative bacteria

目的调查镇江地区临床分离的革兰阴性菌3类整合酶基因的检出情况,分析I类整合子-基因盒结构特征。方法对临床收集的细菌采用PCR方法、T-A克隆以及基因测序技术对3类整合酶基因以及I类整合子的结构进行分析。结果296株革兰阴性肠杆菌科细菌和不发酵糖菌中I类整合酶基因的检出率最高为43.2%。其中在大肠埃希菌、肺炎克雷伯菌、鲍曼不动杆菌和阴沟肠杆菌中的检出率分别为61.0%、14.3%、37.3%和20.0%,而Ⅱ、Ⅲ类基因的检出率较低。对I类整合子基因盒结构分析发现共检测到5种不同基因盒,分别为:dfrA17、aadA5、aadA1、aadA2、dhrfⅪ,有4种不同的基因盒排列方式。结论镇江地区临床分离的细菌I类整合子-基因盒检出率较高。

Objective To investigate class 1,2 and 3 integron-associated integrase genes in gram negative bacteria,and analyze the structure of class 1 integron.MethodsPCR,T-A clone and sequencing were used to amplify and analyze integrase genes and the structure of class 1 integron.ResultsThe prevalence of class I integrase gene was 43.2%,including 61.0% in E.coli,14.3% in K.pneumoniae,37.3% in A.baumannii,and 20% in E.cloacae.The prevalence of integrase genes encoding class Ⅱ and Ⅲ integrase was very low.We identifie...