产超广谱酶β-内酰胺酶大肠埃希氏菌Ⅰ类整合子检测与耐药性关系

发布时间：2018-04-09 13:10

本文选题：超广谱酶β-内酰胺酶　切入点：大肠埃希氏菌　出处：《大连医科大学》2006年硕士论文

【摘要】： 细菌中可移动遗传单位如:质粒、转座子和整合子可以携带编码耐药基因的基因盒。整合子是耐药基因水平转移的主要因子。整合子通过位点特异的基因重组在临床细菌耐药性传播中起重要作用。根据整合酶基因intI的序列不同将整合子划分成四种类型,其中第一类整合子最常见,决定着细菌的多重耐药。目前已在革兰氏阴性菌中发现插入整合子的许多耐药基因盒,在I类整合子中有50多种不同的基因结构,可编码60多个基因盒,介导对氨基糖苷类、青霉素类、头孢菌素类、碳青霉烯类、利福平、磺胺增效剂、氯霉素、红霉素和四价铵化合物等的耐药。产ESBLs菌株在整合子水平转移的介导下能增加捕获这些基因盒的可能性,更有利于耐药基因的传递和扩散。目的:了解I类整合子在产ESBLs和非产ESBLs以及健康人群大肠埃希氏菌中分布流行状况,分析I类整合子在细菌多重耐药中的作用。方法:用VITEK-AMS微生物自动分析仪鉴定细菌和药敏试验,用双纸片协同试验检测产ESBLs菌。用PCR方法扩增I类整合酶基因,经电泳后检测扩增产物。用χ2检验进行统计学分析,P0.05被认为有差异。结果: 140株大肠埃希氏菌检出I类整合子48株,检出率为34.3%。I类整合子在产ESBLs菌(c-ESBLs)的分布明显高于非产ESBLs菌(c-nESBLs)和健康人群(h-n ESBLs ),检
[Abstract]:Mobile genetic units in bacteria such as plasmids transposons and integrons can carry boxes of genes that encode drug-resistant genes.Integron is the main factor of drug resistance gene level transfer.Integron plays an important role in the transmission of drug resistance of clinical bacteria through locus-specific gene recombination.Integrons are divided into four types according to the sequence of integrase gene intI. The first type of integron is the most common, which determines the multidrug resistance of bacteria.At present, many drug-resistant gene cassettes inserted integron have been found in Gram-negative bacteria. There are more than 50 different gene structures in class I integron, which can encode more than 60 gene cassettes, mediating p-aminoglycoside, penicillin, cephalosporins.Carbapenem, rifampicin, sulfonamide synergist, chloramphenicol, erythromycin and tetravalent ammonium compounds resistance.The possibility of capturing these gene cassettes can be increased by ESBLs producing strain mediated by horizontal transfer of integron, which is more favorable to the transmission and diffusion of drug resistance genes.Objective: to investigate the distribution and prevalence of class I integron in ESBLs producing, non producing ESBLs and healthy individuals, and to analyze the role of class I integron in multidrug resistance of bacteria.Methods: VITEK-AMS microorganism automatic analyzer was used to identify bacteria and drug sensitivity test, and double disk synergy test was used to detect ESBLs producing bacteria.Class I integrase gene was amplified by PCR, and the products were detected by electrophoresis.蠂 2 test was used for statistical analysis. P0.05 was considered to be different.Results: 48 strains of class I integron were detected from 140 strains of Escherichia coli. The positive rate of class I integron in ESBLs producing strain c-ESBLswas significantly higher than that of non-#en1# producing strain c-nESBLs) and healthy population.
【学位授予单位】：大连医科大学
【学位级别】：硕士
【学位授予年份】：2006
【分类号】：R378

【参考文献】