利奈唑胺耐药肠球菌耐药机制分析  

Analysis on the mechanism of linezolid-resistant Enterococcus

作　　者：王立朋[1] 何云燕[2] 严立[1] 王慧娟[1] 梁树梅[1] 夏云[1] 

机构地区：[1]重庆医科大学附属第一医院检验科,重庆400016 [2]重庆市中山医院检验科,重庆400013

出　　处：《临床检验杂志》2013年第8期625-628,共4页Chinese Journal of Clinical Laboratory Science

基　　金：国家临床重点专科建设项目[财社2010(305)号]

摘　　要：目的探讨利奈唑胺耐药肠球菌的相关耐药机制。方法对临床分离到的10株利奈唑胺耐药肠球菌,分别提取基因组DNA及质粒DNA,采用PCR技术分别扩增23S rRNA的V583区片段、编码核糖体蛋白的L3、L4基因片段及cfr基因片段。阳性扩增产物进行测序并与标准菌株ATCC 29212进行比对,分析有无突变点。结果 10株利奈唑胺耐药肠球菌均PCR扩增出V583区、L3、L4目的基因,测序未检测到23S rRNA的V583区域发生点突变G2576T以及L3、L4基因突变所引起氨基酸序列的改变。10株细菌均未检测到cfr基因。结论我院分离的肠球菌未发现利奈唑胺耐药机制G2576T突变,L3、L4基因突变导致氨基酸序列改变及多重耐药基因cfr基因的存在,推断利奈唑胺耐药肠球菌仍存在未知的耐药机制。Objective To investigate the mechanism of linezolid-resistant Enterococcus.Methods Genome and plasmid DNA were extracted from 10 clinical isolates of linezolid-resistant Enterococcus.Then,the V583 domain of 23S rRNA,the L3 and L4 gene fragments encoded ribosomal protein and cfr gene were amplified by PCR,respectively.Positive amplification products were sequenced and the obtained sequences were compared with that of ATCC 29212 standard strain to detect the mutation sites.Results The V583 domain of 23S rRNA,and the L3 and L4 gene fragments were all amplified from 10 isolates successfully.Moreover,sequencing showed no any mutation for them.However,the cfr gene was not detected from all 10 isolates.Conclusion All the linezolid-resistant mechanisms,including G2576T mutation in 23S rRNA,amino acid mutation in L3 and L4 genes and the existence of multidrug-resistant cfr gene,were not found in 10 clinical isolates from our hospital,indicating that some unknown mechanism of linezolid-resistant Enterococcus may be existed.

关 键 词：利奈唑胺 肠球菌 耐药 cfr基因 

分 类 号：R446.5[医药卫生—诊断学]