产超广谱β内酰胺酶大肠埃希菌耐药株中整合子基因研究

Integron-mediated multidrug resistance in clinial ESBLs-producing Escherichia coli

目的 探讨整合子介导的耐药机制在产超广谱 β内酰胺酶 (ESBLs)大肠埃希菌多重耐药性中的作用。方法 设计整合子特异引物 ,采用聚合酶链反应 (PCR)技术检测耐药菌中的整合子基因 ,并应用PCR定位 (mapping)技术和DNA测序研究整合子内携带的耐药基因。 结果 4 4 4 %的产ESBLs的大肠埃希菌整合子检测阳性 ,发现 5 5 0 ,130 0 ,180 0bp和 2 6 0 0bp等 4种不同大小的整合子结构 ,其中 6 6 6 %的整合子大于 5 5 0bp。整合子中分别携带二氢叶酸还原酶、核苷转移酶和β内酰胺酶等耐药基因。结论 产ESBLs的大肠埃希菌中的整合子机制参与了多重耐药的形成 ,因整合子可以携带多种耐药基因 ,容易引起多重耐药的水平传播 ,应引起高度的重视。

Objective To investigate integron-mediated multidrug resistance in clinical ESBLs-producing E.coli.Methods Integron was determined by PCR assay with integron-specific-primer.PCR mapping and DNA sequencing were used to analyze resistance-related gene cassette in ESBLs-producing E.coli.Results 44.4% of ESBLs-producing E.coli were integron-positive.Four kinds of integron were detected.66.6% of integron carried more than one resistant gene. Dihydrofolate reductase, adenyltranaferase and β-lactamase were common gene in integron.Conclusions Integron took part in multiple resistance in ESBLs-producing E.coli We should pay more attention to integron-mediated horizontal transference of multidrug resistance.