临床分离动物源性大肠杆菌周浆蛋白AcrA表达水平的测定

Determination on expression level of membrane fusion protein AcrA in clinical Escherichia coli strains from animals

为研究大肠杆菌周浆蛋白AcrA表达水平与不同动物源性大肠杆菌多重耐药水平之间的关系,将获得的重组阳性质粒pET28a(+)-acrA转化至大肠杆菌BL21(DE3)细胞中,经IPTG诱导表达,得到约42ku的目的蛋白。AcrA蛋白表达产物经侧带法纯化后免疫獭兔,制备抗AcrA的多克隆抗体,采用间接ELISA法检测临床分离的31株不同动物源性大肠杆菌中acrA基因的表达水平。结果显示,随着多数被检大肠杆菌多重耐药水平的提高,AcrA蛋白的表达量有上调的趋势。表明,动物源性大肠杆菌的多重耐药水平与AcrA蛋白的表达水平可能存在相关性。

To elucidate the relationship between membrane fusion protein AcrA of Escherichia coli from different animal species and level of multidrug-resistance,the recombinant pET28a（＋）-acrA was transformed into E.coli BL21（DE3）.The target protein AcrA of 42ku was expressed from E.coli BL21 induced by IPTG.The purified AcrA protein was injected into Rex rabbits and anti-AcrA protein antibodies were prepared.31 strains of E.coli isolated from different animal species were selected to determine the expression level of the acrA gene by indirect ELISA.The results showed that the higher expression level of AcrA protein existed in most of the E.coli with higher multidrug-resistant level.There was relativity in the multidrug resistant level of E.coli isolated from different animal species with the expression level of AcrA protein.