多重耐药铜绿假单胞菌中Ⅰ型整合子新结构的发现及其与耐药的相关性  

Discovery of new structure of class 1 integron in MDR Pseudomonas aeruginosa and its association with drug-resistance

作　　者：朱玉莹[1] 易勇[2] 杨犀[1] 律娜[1] 李晶[1] 朱宝利[1] 胡永飞[1] 

机构地区：[1]中国科学院微生物研究所,北京100101 [2]中国人民解放军第306医院,北京100101

出　　处：《微生物学报》2013年第9期927-932,共6页Acta Microbiologica Sinica

基　　金：国家自然科学基金(31270168)~~

摘　　要：【目的】研究临床多重耐药铜绿假单胞菌中Ⅰ型整合子的结构特征,探讨整合子与细菌多重耐药之间的相关性。【方法】收集临床样品中的铜绿假单胞菌,从中挑选多重耐药菌。采用聚合酶链式反应扩增Ⅰ型整合子可变区,应用酶切方法和DNA测序技术分析整合子基因结构,并采用SPSS19.0软件分析整合子与耐药表型间的相关性。【结果】多重耐药铜绿假单胞菌中Ⅰ型整合子的检出率为27.3%。Ⅰ型整合子基因盒排列形式共有3种(1500 bp、2300 bp和4000 bp),其中2种在其他细菌中也有发现。基因盒所编码的耐药基因有氨基糖苷类抗生素抗性基因(aadA、aadB、aac(6')Ⅱ和aadA13)、β-内酰胺类抗生素抗性基因(blaCARB8和oxa10)和氯霉素外排泵基因(cmlA8),耐药表型相关性分析表明整合子与氨基糖苷类抗生素抗性密切相关。【结论】在多重耐药铜绿假单胞菌临床分离株中发现了3种不同Ⅰ型整合子结构,这3种结构中均含有氨基糖苷类抗生素耐药基因,其中aadB-aac(6')Ⅱ-blaCARB8结构最为流行。[ Objective ] To investigate the characteristics of classⅠ integrons among clinical muhidrug-resistant Pseudomonas aeruginosa isolates, and to analyze the association between class I integrons and muhidrug resistance. [Methods] Pseudomonas aeruginosa strains were isolated from clinical samples, and the multidrug-resistant ones were picked out from these isolates. PCR assays were used to detect the variable regions of class I integrons, and the resulting products were then digested with restriction enzyme Sau 3A Ⅰ and sequenced. SPSS19.0 software was used for statistical analysis. [ Results ] Class I integrons were detected in 27.3% of the clinical multidrug-resistant Pseudomonas aeruginosa isolates. Amplification of variable regions of class Ⅰ integrons revealed three different gene cassette arrays （1500, 2300 and 4000 bp） , two of them were also found in other bacteria. These gene cassette arrays encoded aminoglycoside-modifying enzymes （aadA, aadB, aac（6＇） Ⅱ and aadA13） , 15-1actamases （blaCARB8 and oxalO） and chloromycetin efflux pump （cmlA8）. Analysis results suggested closely relationship between class I integrons and aminoglycoside resistance. [ Conclusion ] We revealed three different gene cassette arrays in the clinical isolates of the muhidrug-resistant Pseudomonas aeruginosa, and gene cassette array aadB-aac（6＇） Ⅱ-blaCARB8 was the most prevalent. The three gene cassette arrays all contained the aminoglycoside-resistant genes.

关 键 词：铜绿假单胞菌 多重耐药 整合子 基因盒 

分 类 号：R373[医药卫生—病原生物学]