【摘要】 目的研究Ⅰ型整合子参与肺炎克雷伯菌耐药的分子机制。方法收集2007年至2010年某院临床分离的297株肺炎克雷伯菌,应用K-B纸片扩散法检测耐药性,采用聚合酶链式反应进行I类整合子整合酶基因的检测;整合子可变区扩增、克隆测序,分析I类整合子基因结构。结果 297株肺炎克雷伯菌中,除MEM、IPM外,对其余11种抗菌素,Ⅰ类整合酶基因阳性菌株的耐药率明显高于Ⅰ类整合酶基因阴性菌株。57.91%(172/297)的菌株I类整合子整合酶基因阳性,共检测出10种不同基因盒。可变区编码耐药基因有aadA2、aadA1、aadA5、aadA3C、aacA4,介导氨基糖苷类抗菌素耐药;dhfrhI、dfrA12、dfrA14、dfrA17、dfrA1、dfrA25、dhfrhI,介导磺胺类抗菌素的耐药;aar-2,介导利福平耐药。结论Ⅰ类整合子在本院临床分离肺炎克雷伯菌中分布较广泛,主要介导氨基糖苷类和磺胺类抗菌素耐药。整合子与肺炎克雷伯菌的耐药有关,在肺炎克雷伯菌耐药性的形成和播散中具有重要作用。更多还原

【Abstract】 Objective To investigate the molecular mechanism of integron mediated resistance in Klebsiella pneumoniae.Methods 297 strains were collected between 2007 and 2010.All strains were tested by K-B method for drug resistance.PCR and DNA sequencing were undertaken to detected intⅠ and clarify the context of gene cassette.Results Susceptibility data showed that strains carrying ClassⅠintegron were significantly more resistant to all of the antibiotics tested then isolates lacking Class Ⅰintegron excepted MEM and IPM.IntⅠ was detected in 57.91%(172/297)of the isolates.Ten types of gene cassettes were identified.The gene cassttes encoded genes resistance aminoglycosides(aadA2,aadA1,aadA5,aadA3C,aacA4),sulfamethoxazole/trimethoprim(dhfrhI,dfrA12,dfrA14,dfrA17,dfrA1,dfrA25,dhfrhI) and rifampicin(aar-2).Conclusions High incidence of class Ⅰ integrons was found in Klebsiella pneumoniae,class Ⅰ integrons mainly mediated the aminoglycosides and sulfa antimicrobial resistance.Close association existed between class Ⅰ integrons and resistance in Klebsiella pneumoniae.更多还原