TolC表达量与大肠埃希菌K-12耐四环素的研究  

Association of TolC expression with resistance to tetracycline in Escherichia coli K-12

作　　者：张丹凤[1] 黄传钟[1] 王三英[1] 

机构地区：[1]厦门大学生命科学学院,厦门361005

出　　处：《中国抗生素杂志》2007年第11期697-700,I0001,共5页Chinese Journal of Antibiotics

摘　　要：随着抗生素的开发与使用,细菌在对多种抗生素的适应过程中逐渐发展出对抗生素耐药的反应机制。TolC是药物排出转运体系的外膜成分,与AcrAB一起形成主要的药物排出泵,有关其表达量与耐药间的关系目前尚不清楚。试验将tolC克隆到pET-32a载体上进行诱导表达,镍柱纯化,免疫新西兰大白兔,获得1:4000的抗血清。Western blotting分析表明,TolC的表达量在耐四环素的大肠埃希菌K-12中比对照组提高50%。细菌TolC高表达试验发现,其MIC从100μg/ml提高到200μg/ml。结果说明TolC的表达量与四环素耐药性直接相关,提示细菌可以通过调节外膜蛋白的表达实现对抗生素的耐受。Association of TolC expression with resistance to tetracycline in Escherichia coli K-12 was studid. TolC was an outer membrane protein, which was bound with AcrAB to form a critical multidrug efflux pump. However, association of TolC amount with drug resistance was ill-defined. In the study, tolC was cloned into pET-32a vector induced expression and its recombinant proteins were purified by Ni-NTA. The purified recombinant proteins were used for preparing of anti-TolC. The prepared antiserum with titer 1 ： 4000 was utilized as the primary antibody in Western blotting. It showed that TolC amount was increased 50% in tetracycline-resistant E. coli K-12 compared to its original control strain. When TolC was overexpressed, the strain showed strong resistance to tetracycline with its MIC from 100μg/ml to 200μg/ml. These findings indicated that TolC amount was directly correlated to bacterial resistance to tetracycline, suggesting that bacteria mounted an adaptive feedback to antibiotics by regulating outer membrane protein expression.

关 键 词：TOLC 耐药性 大肠埃希菌K-12 四环素 

分 类 号：R378.21[医药卫生—病原生物学]