一种新的质粒介导的IMI-1型碳青霉烯酶  

A novel plasmid-mediated IMI-1-like carbapenemase

作　　者：杜小幸[1] 周志慧[1] 俞云松[1] 陈亚岗[1] 李兰娟[1] 马亦林[1] 

机构地区：[1]浙江大学医学院附属第一医院传染科,杭州310003

出　　处：《中华微生物学和免疫学杂志》2004年第10期819-822,共4页Chinese Journal of Microbiology and Immunology

基　　金：国家自然科学基金资助项目 (编号 :3 0 2 70 0 74)

摘　　要：目的　确立亚胺培南耐药阴沟肠杆菌对亚胺培南的耐药机制。方法　采用Etest测定抗菌药物最低抑菌浓度 (MIC) ,通过等电点聚焦电泳 (IEF)、三维试验、接合试验、Southern杂交、聚合酶链反应 (PCR)、克隆测序对酶的活性及编码基因进行研究。结果　阴沟肠杆菌产碳青霉烯酶 ,等电点为 8.1。该酶能被克拉维酸抑制 ,不被氯唑西林、EDTA抑制 ,存在 2f类酶的某些特性 ,其耐药基因位于 80kb左右的质粒上。克隆测序显示与染色体介导的IMI 1有 99%的同源性。结论　阴沟肠杆菌对亚胺培南耐药是由一种新的质粒介导的与染色体介导的IMI 1类似的碳青霉烯酶所致。Objective To investigate the resistant mechanism of imipenem-resistant Enterobacter cloacae. Methods The minimal inhibitive concentration (MIC) was detected by E test. Isoelectric focusing electrophoresis(IEF), three dimensional test, conjugation experiment, Southern blot, polymerase chain reaction(PCR), cloning and sequencing methods were applied for analyzing the enzyme activity and the encoding gene. Results The carbapenemase produced by Enterobacter cloacae had the bands with pIs 8.1. The carbapenemase had some characteristics of Class 2f. The activity of hydrolysising imipenem was inhibited by clavulanic acid, but not inhibited by cloxacillion and EDTA. The imipemen-resistant gene was located on a about 80kb plasmid and the amino acid sequence have 99% of homology with chromosome-mediated IMI-1. Conclusion The E. cloacae resistant to imipenem was explained by a novel plasmid-mediated IMI-1-like carbapenemase.

关 键 词：碳青霉烯酶 阴沟肠杆菌 亚胺培南 质粒介导 染色体介导 三维试验 最低抑菌浓度(MIC) 克隆测序 等电点 SOUTHERN杂交 

分 类 号：R378[医药卫生—病原生物学]