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• 生命科学 • 上一篇    下一篇

定点突变内皮抑素Zn2+的结合位点及突变基因的克隆表达

王 群1 ,马 军2, 何 巍2, 王 晖 2   

  1. 1.中国科学院长春应用化学研究所稀土化学与物理国家开放实验室生物无机组, 长春 130022 2.中国生物技术集团总公司长春生物制品研究所, 长春 130062
  • 收稿日期:2004-05-26 修回日期:1900-01-01 出版日期:2005-01-26 发布日期:2005-01-20
  • 通讯作者: 王 群

Site Directed Mutation on Zn2+ Binding Site of Endostatin and Cloning, Expression of Mutant Gene

WANG Qun1, MA Jun2, HE Wei2, WANG Hui2   

  1. 1. National Key Laboratory of Rare Earth Chemistry and Physics, Changchun Institute of Applied Chemistry, the Chinese Academy of Sciences, Changchun 130022, China; 2. Changchun Institute of Biological Products, China National Biological Technology Corporation, Changchun 130062, China
  • Received:2004-05-26 Revised:1900-01-01 Online:2005-01-26 Published:2005-01-20
  • Contact: WANG Qun

摘要: 从人胚肝组织中提取总RNA, 以逆转录聚合酶链式反应(RT-PCR)法获得人内皮抑素编码序列, 采用定点突变技术将His2和His4双突变为Leu2和Val4. 将突变基因cDNA插入含有T7启动子的质粒pET-28b中构建表达质粒pMendo, 转化大肠杆菌BL21(DE3), 筛选表达菌株BL21-Mute, 表达菌株经IPTG诱导后以包涵体方式产生大量内皮抑素突变蛋白. SDS-PAGE分析表明, 表达的重组蛋白占菌株可溶性蛋白质的30%. 复性、 纯化的内皮抑素突变蛋白纯度达到98%, 失去抑制人脐静脉内皮细胞增殖的活性.

关键词: 内皮抑素, 克隆, 突变, 大肠杆菌

Abstract: Human endostatin cDNA was cloned from total RNA of human embryo liver tissue by RT-PCR. Endostatin DNA sequence encoded His2 and His4 were double changed to Leu2 and Val4 using site directed mutation technique. The mutant endostatin cDNA was inserted into the pET28b containing promoter T7. The recombinant plasmid transformed the E.coli BL21(DE3). Recombinant human endostatin was highly expressed as inclusion body when theexpression strain BL21-Mute was induced with IPTG. The result of SDS-PAGE analysis reveals that recombinant mutant endostatin accounts for up to 30% of soluble protein in E.coli. The mutant endostatin was purified and refolded farther, its purity was up to 98%. Recombinant mutant endostatin was inactive in inhibiting endothelial cell proliferation.

Key words: endostatin, cloning, mutant, E.coli

中图分类号: 

  • Q784