幽门螺杆菌Omp22-HpaA融合基因工程菌蛋白的表达

目的:优化幽门螺杆菌Omp22-HpaA基因工程菌pMAL-c2X-Omp22-HpaA-TB1的表达条件,并对其表达产物进行纯化和鉴定.方法:在不同诱导时机、不同诱导剂(IPTG)浓度和不同诱导时间条件下诱导pMAL-c2X-Omp22-HpaA-TB1的表达,测定目的蛋白的表达量.在优化条件下诱导工程菌表达,并应用SDS-PAGE方法对表达产物进行分析,采用Amyloss树脂预装柱对可溶性Omp22-HpaA蛋白进行分离、纯化,对纯化后的蛋白行Western blot分析.结果:工程菌培养2 h时加入IPTG(终浓度为0.4 mmol/L)诱导7 h,目的蛋白Omp22-HpaA表达量达到菌体总蛋白的20%以上.经纯化得到了较高纯度(＞90%)的目的蛋白,并具有良好的免疫原性.结论:建立了从pMAL-c2X-Omp22-HpaA-TB1可溶性表达产物中纯化较高纯度Omp22-HpaA融合蛋白的方法.

Expression of Omp22-HpaA fusion gene from Helicobacter pylori in E.coli

Aim: To optimize the expression conditions of pMAL-c2X-Omp22-HpaA-TB1 and purify its expressing products. Methods:pMAL-c2X-Omp22-HpaA-TB1 were induced by different contents of IPTG for different inducing time at different inducing opportunity. The expression products were analyzed using SDS-PAGE method;soluble Omp22-HpaA protein was purified by amyloss pre-packed column and then the purity was detected with Western blot.Results: The gene engineering E.coli strain growing two hours was induced for seven hours by 0.4 mmol/L IPTG,the expression amounts offusion protein took account for 20% of the total bacterium protein, and the purity of Omp22-HpaA protein was confirmed to more than 90%. Omp22-HpaA had a high immunocompetence.Conclusion: An effective method for purifying Omp22-HpaA fusion protein from soluble offspring was established.