Sumo分子伴侣与富含二硫键的抗真菌肽Drs基因的融合有助于其可溶性表达

利用PCR引物延伸的方法合成了分子伴侣Sumo和抗真菌肽Drosomycin的融合基因，将其插入到表达载体pET-3c中，构建出重组表达质粒pET-3c-SD，并转化至大肠杆茵BL21(DE3)中。筛选重组转化子，进行表达条件的优化和表达产物的可溶性分析。结果表明在30℃条件下，用0.5mM IPTG诱导3h 后，目的蛋白表达量最高，约占菌体总蛋白的22％，其中可溶性蛋白超过了目的蛋白的80%。经过Ni-NTA纯化后，融合蛋白的纯度可达95％以上。抑菌实验表明，该融合蛋白对白僵菌（Beauveria bassiana）具有一定的抑真菌活性。本研究证实了使用分子伴侣Sumo融合表达对具有多个二硫键的小分子多肽的表达是非常有效的。

Fusion Protein on Sumo Molecular Chaperone and Antifungal Peptide Drs Help to Soluble Expression

After Sumo molecular chaperone and antifungal peptide Drosomycin were synthesized by PCR,the recombinant plasmid pET-3c-SD was constructed successfully.After the recombinant plasmid was transformed into BL21(DE3),fusion proteins expressed in the E.coli 21(DE3)by the induction of IPTG.Target proteins attained 80 percent in total proteins.Meantime,Soluble protein exceeds 80% in total target proteins.The fusion protein was purified by Ni-NTA affinity chromatography,and its purification exceeds 95 percent.The experiment shows the fusion protein own the antifungal activity,and this construction strategy help to facilitate small molecular peptide expression that had several two disulfide bonds.