碳青霉烯类耐药弗劳地枸橼酸杆菌中质粒介导blaNDM-1基因的研究  

Study on plasmid-mediated bla_(NDM-1) gene in carbapenem-resistant Citrobacter freundii

作　　者：杜娜 林云[1] 刘淑敏[2] 牛敏[2] 李亚波[1] 施雄飞[1] 周芳[1] 尧静 张孟爽 杜艳[2] DU Na;LIN Yun;LIU Shumin;NIU Min;LI Yabo;SHI Xiongfei;ZHOU Fang;YAO Jing;ZHANG Mengshuang;DU Yan(Department of Laboratory Medicine,Yunnan Provincial Hospital of Traditional Chinese Medicine,Kunming 650021,China)

机构地区：[1]云南省中医医院检验科,昆明650021 [2]昆明医科大学第一附属医院检验科,云南省实验诊断研究所,云南省检验医学重点实验室

出　　处：《中国感染与化疗杂志》2018年第6期604-607,共4页Chinese Journal of Infection and Chemotherapy

基　　金：云南省医疗卫生单位内设研究机构科研项目(2016NS030)。

摘　　要：目的研究碳青霉烯类耐药弗劳地枸橼酸杆菌中bla_(NDM-1)基因的传播特征。方法收集昆明医科大学第一附属医院2012年6月-2014年10月产NDM-1酶弗劳地枸橼酸杆菌18株,采用VITEK 2全自动鉴定药敏仪进行菌种鉴定和药敏试验;通过接合试验、脉冲场凝胶电泳(PFGE)及Southern印迹杂交试验对bla_(NDM-1)基因的水平传播机制进行研究。结果 18株细菌对青霉素类、头孢菌素类、碳青霉烯类抗生素的耐药率为100%,对其他抗生素也呈现不同程度的耐药;13株细菌接合试验成功,接合子对碳青霉烯类抗生素耐药;PFGE及Southern印迹杂交试验表明16株细菌中bla_(NDM-1)基因均位于约33.3kb大小的质粒上,剩余2株细菌的bla_(NDM-1)基因位于33.3～54.7kb大小的质粒上。结论质粒介导碳青霉烯类耐药弗劳地枸橼酸杆菌中bla_(NDM-1)基因水平转移。Objective To investigate the transmission of blaNDM-1 gene in carbapenem-resistant Citrobacter freundii.Methods A total of 18 strains of NDM-1-producing C.freundii were collected from the First Affiliated Hospital of Kunming Medical University during the period from June 2012 to October 2014.The isolates were identified and subjected to antimicrobial susceptibility testing with VITEK 2 System.Conjugation experiments,pulsed-field gel electrophoresis(PFGE)and Southern blot hybridization were performed to determine the transferability of plasmids.Results The antibiotic susceptibility results showed that all the NDM-1-producing C.freundii isolates were resistant to penicillins,cephalosporins and carbapenems.All isolates exhibited different level resistance to other antibiotics.Conjugation experiments revealed that the plasmids harboring blaNDM-1 in 13 strains were transformed into E.coli 600,and exhibited carbapenem resistance.PFGE and Southern blot hybridization found that blaNDM-1 was located on a 33.3 kb plasmid in 16 isolates and on 33.3-54.7 kb plasmid in 2 isolates.Conclusions Our findings suggest that plasmids contribute to the horizontal dissemination of blaNDM-1 gene in carbapenemresistant C.freundii.

关 键 词：blaNDM-1基因 质粒 弗劳地枸橼酸杆菌 传播机制 

分 类 号：R978.1[医药卫生—药品]