应用自动诱导表达体系提高原核表达效率

自动诱导表达体系是依据T7表达菌株对于培养基中的碳源和能源的利用机制建立起来的，用于生产各种异源蛋白更加高效、便捷和经济。为提高重组蛋白在原核细胞中的表达效率，构建了以S基因抗原位点区作为目的基因的原核表达重组质粒pET-S1，并将其转化入大肠杆菌（Escherichia coli）BL21（DE3）菌株。用IPTG诱导表达系统和自动诱导表达系统分别对目的蛋白进行表达。结果表明，目的蛋白最高表达量分别占菌体总蛋白的25.9 %和45.1 %，表明自动诱导表达系统可明显提高表达效率。

Higher Prokaryotic Expression Efficiency Achieved by Auto-induction Expression System

To obtain the higher expression efficiency of producing recombinant protein in Escherichia coli, the prokaryotic expressing vector pET-S1, which contained whole antigenic sites of S gene from swine transmissible gastroenteritis coronavirus (TGEV), was constructed and transformed into E.coli strain BL21 (DE3). The target protein was expressed by the IPTG inducing expression system and auto-induction expression system, respectively. The highest amount of target protein accounted for 25.9% and 45.1% of total bacteria protein, respectively， indicating that the expression efficiency was significantly improved by auto-induction expression system.