具有GPx和SOD双酶活性含硒76肽的制备及其穿膜效应

Preparation of a 76-Mer Selenium-Containing Peptide with GPx and SOD Double Enzyme Activity and Its Cell-Penetrating Effects

根据模块酶原理设计一种嵌有穿膜结构域序列并具有谷胱甘肽过氧化物酶(GPx)和超氧化物歧化酶(SOD)双酶活性的含硒76肽(Se-CuZn-76P),利用半胱氨酸缺陷表达法在单一蛋白生产(SPP)系统表达该肽,并鉴定其穿膜效应.实验结果表明:该方法可成功表达纯度较高的Se-CuZn-76P,并且每毫克蛋白表现出109μmol/min的GPx活力和1 218μmol/min的SOD活力;在Se-CuZn-76P存在的环境中培养肝L02细胞一段时间后,细胞内的GPx和SOD活力分别升高1.65和4.12倍,且Se-CuZn-76P可顺利进入L02细胞.

A 76-mer selenium-containing peptide （Se-CuZn-76P） with double glutathione peroxidase （GPx） and superoxide dismutase （SOD） activity, which was embedded in a sequence of membrane- penetrating domain, was designed according to the principles of module enzyme, and was expressed by the method of cysteine auxotrophic expression in a single protein production （SPP） system, then the cell-penetrating effects of Se-CuZn-76P were identified. Experimental results show that the method can successfully express the high purity of Se-CuZn-76P, and demonstrate GPx activity （109 gmol/min） and SOD activity （1 218μmol/min） per mg of protein. The GPx activity and the SOD activity in hepatic L02 cells are increased by 1.65 and 4.12 times respectively, when L02 cells are cultured for a period of time in the presence of Se CuZn-76P, and Se CuZn-76P can be successfully entered into L02 cells.