金黄色葡萄球菌sPP2C的克隆、表达及性质研究  

Cloning,Expression and Property of Protein Phosphatase 2C of Staphylococcus Aureus

作　　者：郭伟伟[1] 倪晓华[1] 

机构地区：[1]华东师范大学生命科学学院,上海200062

出　　处：《华东师范大学学报（自然科学版）》2007年第4期107-111,131,共6页Journal of East China Normal University(Natural Science)

基　　金：上海市自然科学基金(04ZR14040)

摘　　要：从金黄色葡萄球菌基因文库中克隆了一条新的双特异性磷酸酶,命名为sPP2C(protein phosphatase 2C,Staphylococcus aureus).sPP2C基因具有741个碱基,编码的蛋白有247个氨基酸,具有一个蛋白磷酸酶2C的催化结构域.sPP2C的分子量为26.1kD,等电点为4.95.在E.Coli.Rossetta中表达蛋白sPP2C.高纯度的sPP2C用亲和层析的方法纯化得到.酶学研究结果表明:sPP2C对磷酸酶的通用底物硝基苯磷酸(p-nitrophenyl phosphate,pNPP)不起作用,而与pSer/Thr和pTyr的寡肽均有去磷酸化作用.这些实验结果说明sPP2C是一个新的双特异性磷酸酶.A novel dual specificity protein phosphatases named sPP2C （protein phosphatase 2C, Staphylococcus aureus） was cloned from Staphylococcus aureus gene library, sPP2C gene contained 741 bp. The protein contained 247 amino acids and a protein phosphatases 2C; catalytic do main. The molecular weight was 26. 1 kDa, and pI was 4. 95. sPP2C was expressed in Ecoli. Rossetta and purified by affinity chromatography. Enzyme property research revealed that sPP2C showed no phosphatase activity towards pNPP（p-nitrophenyl phosphate）which is a common syn etic protein phosphatase substrate, whereas sPP2C showed phosphatase activity towards oligope tptides containing pSer/Thr and pTyr, indicating that sPP2C is a novel protein phosphatase with dual substrate specificity.

关 键 词：sPP2C PNPP 双特异性磷酸酶 磷酸酶活性 

分 类 号：Q26[生物学—细胞生物学]