产气肠杆菌对碳青霉烯类抗生素的耐药机制研究  

Resistance mechanism of Enterobacter aerogenes to carbapenems

作　　者：刘瑛[1] 俞静[1] 费奇力[1] 沈立松[1] 

机构地区：[1]上海交通大学医学院附属新华医院检验科,上海200092

出　　处：《上海交通大学学报（医学版）》2013年第3期275-279,共5页Journal of Shanghai Jiao tong University:Medical Science

基　　金：上海市卫生局资助课题(2010024)~~

摘　　要：目的探讨产气肠杆菌对碳青霉烯类抗生素的耐药机制。方法收集耐碳青霉烯类抗生素产气肠杆菌16株,采用改良Hodge试验筛选产碳青霉烯酶菌株;采用PCR扩增和基因测序技术检测并验证耐药基因;利用聚丙烯酰胺凝胶电泳(SDS-PAGE)对菌株的外膜蛋白进行分析。结果改良Hodge试验结果发现16株产气肠杆菌均产碳青霉烯酶;PCR扩增和基因测序结果显示16株产气肠杆菌均存在KPC-2基因,但未携带IMP-1、IMP-2、VIM-1、VIM-2、NDM-1、OXA-1和OXA-9等其他碳青霉烯酶基因;SDS-PAGE电泳结果显示16株产气肠杆菌中有5株出现Omp36膜孔蛋白的缺失。结论 16株耐碳青霉烯类抗生素产气肠杆菌主要耐药机制可能与产KPC-2型酶且部分菌株合并Omp36膜孔蛋白的缺失有关。Objective To investigate the resistance mechanism of Enterobacter aerogenes to carbapenems. Methods Sixteen isolates of carbapenem-resistant Enterobacter aerogenes were collected, and modified Hodge test was used to screen the strains producing carbapenemase. PCR amplification and gene sequencing were employed to detect and verify the resistance-associated gene. Sodium dodecyl sulfate-polyacrylamide gel electrophoresis （SDS-PAGE） was adopted to analyze the outer membrane porin of the strains. Results Modified Hodge test revealed that all the 16 strains of Enterobacter aerogenes produced carbapenemase. PCR amplification and gene sequencing indicated that all the 16 strains of Enterobacter aerogenes possessed KPC-2 gene, but did not carry IMP-l, IMP-2, VIM-l, VIM-2, NDM-1, OXA-1 and OXA-9 carbapenemase gene. SDS-PAGE demonstrated that Omp36 porin was absent in 5 of the 16 strains of Enterobacter aerogenes. Conclusion The major resistance mechanism of 16 strains of Enterobacter aerogenes to carbapenem may be associated with the expression of KPC-2 cabarpenemase accompanied with the absence of Omp36 porin in some strains.

关 键 词：产气肠杆菌 耐药机制 碳青霉烯酶基因 外膜蛋白 

分 类 号：R446.5[医药卫生—诊断学]