一株广泛耐药恶臭假单胞菌耐药机制研究  

Mechanism of drug resistance of a strain of extensively drug resistant Pseudomonas putida

作　　者：李军[1] 邹明祥[1] 王海晨[1] 胡咏梅[1] 豆清娅[2] 晏群[1] 刘文恩[1] 

机构地区：[1]中南大学湘雅医院检验科,湖南长沙410008 [2]中南大学湘雅医院医院感染控制中心,湖南长沙410008

出　　处：《中国微生态学杂志》2016年第1期1-5,共5页Chinese Journal of Microecology

基　　金：湖南省发改委(湘发改高技[2012]1493号);湖南省发改委(湘发改投资[2014]658号);湖南省自然科学基金(14JJ7003)

摘　　要：目的研究一株临床分离广泛耐药恶臭假单胞菌(extensively drug resistant Pseudomonas putida,XDR-PP)的耐药机制,以期指导临床合理使用抗菌药物。方法采用VITEK-2compact全自动微生物分析系统对菌株进行鉴定及药敏试验;改良Hodge试验初筛碳青霉烯酶;EDTA-亚胺培南协同试验和亚胺培南双纸片增效法初筛金属酶;PCR检测16SrRNA甲基化酶基因、金属β-内酰胺酶基因及可移动性遗传元件基因,产物测序,结果经BLAST软件比对分析。结果该菌株对所检测的抗菌药物均耐药。改良Hodge试验、EDTA-亚胺培南协同试验和亚胺培南双纸片增效法结果均为阳性。基因检测结果显示,金属β-内酰胺酶基因阳性的有blaVIM-2和blaIMP-4两种基因,16SrRNA甲基化酶基因阳性的有armA基因,13种可移动性遗传元件中,intI、tnpU和merA基因阳性,其余均为阴性。结论blaVIM-2、blaIMP-4、armA、intI、tnpU以及merA基因是导致其广泛耐药的重要机制。恶臭假单胞菌中同时检出blaVIM-2和blaIMP-4两种金属β-内酰胺酶基因及armA基因为国内首次报道。Objective To study the molecular mechanism of drug resistance of an extensively drug resistant Pseudomonas putida,and provide the basis for clinical rational use of antimicrobial drugs.Methods Re-identification and antibiotic susceptibility of the strain were performed by VITEK-2.Carbapenemases were screened by modified Hodge test.EDTA synergy test and combination disk diffusion test were used for phenotypic screening of metallo-β-lactamase（MBL）.Detection of 16 SrRNA methylase genes,metallo-β-lactamase genes and mobile genetic elements were performed by using PCR method,and the products were sequenced and analyzed with BLAST software.Results The strain was resistant to all the testing antimicrobial agents.The results of modified Hodge test,EDTA-imipenem synergy test and combination disk diffusion test were all positive.Two kinds of metallo-β-lactamase genes（blaVIM-2and blaIMP-4）and 16 SrRNA methylase gene（armA）were simultaneously detected.Among the 13 kinds of mobile genetic elements,three kinds were detected,including intI,tnpUand merA.Conclusion Coexistance of blaVIM-2,blaIMP-4,armA,intI,tnpUand merAgenes are the important reasons which lead to the extensive resistance.This is the first report that two kinds of metallo-β-lactamase genes including blaVIM-2and blaIMP-4and the gene armA were detected simultaneously in Pseudomonas putida（PP）in China.

关 键 词：广泛耐药 恶臭假单胞菌 金属β-内酰胺酶基因 16SrRNA甲基化酶基因 可移动性遗传元件 

分 类 号：R378[医药卫生—病原生物学]