中文摘要：

目的研究二硫键C16-C36和C22-C46对镇痛抗肿瘤缬精甘肽BmK AGAP镇痛活性的影响。方法使用本实验室已构建成功的2个二硫键双突变体（C16S,C36S）和（C22S,C46S）,在大肠杆菌中诱导表达,通过金属离子螯合亲和层析和阳离子交换层析方法对突变体蛋白分离纯化,采用小鼠醋酸扭体法测定2个突变体的镇痛活性,圆二色谱分析BmK AGAP和2个二硫键突变体的二级结构变化差异,利用生物信息学的方法模建BmK AGAP的三维空间结构。结果 a.目的蛋白在大肠杆菌BL21（DE3）中实现了可溶性表达;b.采用金属离子螯合亲和层析和阳离子交换层析方法获得了电泳纯样品;c.2个双突变体（C16S,C36S）和（C22S,C46S）的镇痛活性与阳性对照组rBmKAGAP比较均下调,具有显著性差异。结论二硫键C16-C36和C22-C46在保持和调节BmK AGAP的镇痛生物活性方面具有重要作用。

英文摘要：

Objective To research the contribution of two disulfide bonds to the analgesic activity of antitumor-analgesic scorpion peptide BmK AGAP.Methods Two mutants（C16S,C36S） and（C22S,C46S） were expressed in E.coli BL21（DE3）,and purified by metal chelating affinity chromatography and ion exchange chromatography.The analgesic activity was detected by the mouse twisting action model.Circular Dichroism（CD） spectra was used to analyze the differences of secondary structures among BmK AGAP and two mutants.Utilizing bioinformatic method to model the three dimensitional structure of BmK AGAP.Results The two mutants were expressed in E.coli BL21（DE3） in soluble form,and then purified by two steps of chromatography.Compared to rBmK AGAP,both of the two mutants revealed a decrease in analgesic activity.Conclusions The two disulfide bonds C16-C36 and C22-C46 play important roles in maintaining and regulating the analgesic activity of the antitumor-analgesic scorpion peptide BmK AGAP.