幽门螺杆菌HspA-UreB融合蛋白的诱导表达与活性鉴定

目的：优化幽门螺杆菌HspA-UreB融合蛋白诱导表达的条件，以提高目的蛋白的产量。方法：表达幽门螺杆菌HspA-UreB融合蛋白的重组基因工程菌BL21（pET-HU27）在不同温度下（25℃、37℃）以不同的IPTG浓度（0.3、1.0和2.0 mmol·L^-1）和不同的培养基（LB、SOC）中分别诱导表达不同时间，表达产物经超声破碎后，进行融合蛋白可溶性分析，并用Western blotting 对表达产物进行鉴定。结果：SDS-PAGE结果显示，37℃时，LB培养基中，0.3 mmol·L^-1的IPTG浓度诱导5 h时，融合蛋白的含量最高为21.51%；25℃，SOC培养基中，1.0 mmol·L^-1的IPTG浓度诱导8 h时，可溶性HspA-UreB融合蛋白含量最高为34.58%，表达产物能够被免疫小鼠血清识别。结论：实现了幽门螺杆菌HspA-UreB融合蛋白在原核细胞中的高效表达，并具有良好的免疫活性，为进一步开发应用以该融合蛋白为抗原的幽门螺杆菌疫苗打下了坚实的基础。

Expression and characterization of recombinant HspA-UreB fusion protein of Helicobacter pylori

Objective To optimize the expression condition and increase the output of recombinant HspA-UreB fusion protein of Helicobacter pylori.Methods The recombinant HspA-UreB fusion protein of Helicobacter pylori cloned in E.coli BL21 was expressed in different revulsive concentrations(0.3,1.0 and 2.0 mmol·L~(-1)) and culture medium(LB,SOC) at different temperatures(25℃,37℃) for different time,the offsprings expressed in E.coli BL21(pET-HU27) were broken up with ultrasonic,and Western blotting test was used to detect the offsprings.(Results The output) of this fusion protein was highest in LB culture medium in 0.3 mmol·L~(-1) IPTG concentration at 37℃ for 5 h,and the percentage of soluble fusion protein was highest in SOC culture medium in(1.0 mmol·L~(-1)) IPTG concentration at 25℃ for 8 h,and the offspring could be recognized specifically by mouse serum.(Conclusion HspA-UreB) fusion protein of Helicobacter pylori is expressed with high efficiency and with good immunoactivity,and which will help to develop gene recombinant vaccine against Helicobacter pylori infection.