吉林大学学报(医学版)

• 基础研究 • 上一篇    下一篇

rhKD/APPvar毕赤酵母分泌表达质粒的构建及其重组蛋白的表达和纯化

王心童1,王虹蛟2,王强2,孟威宏3,颜炜群4,任立群4   

  1. 1.吉林大学中日联谊医院神经内科,吉林 长春130033;2.解放军第461医院内科,吉林 长春130021;3.沈阳军区总医院心血管内科,辽宁 沈阳110015;4.吉林大学再生医学科学研究所再生医学系,吉林 长春130021
  • 收稿日期:2013-10-17 出版日期:2014-05-28 发布日期:2014-06-05
  • 通讯作者: 孟威宏(Tel:024-28856101,E-mail:wqwhj461@163.com) E-mail:wqwhj461@163.com
  • 作者简介:王心童(1989-),女,吉林省长春市人,在读医学硕士,主要从事再生医学和神经病学研究。
  • 基金资助:

    国家自然科学基金资助课题(30300153)

Construction of secretory expression vector of rhKD/APPvar and  expression and purification of  its recombinant protein in Pichia pastoris

WANG Xin-tong1,WANG Hong-jiao2,WANG Qiang2,MENG Wei-hong3,YAN Wei-qun4,REN Li-qun4   

  1. 1. Department of Neurology,China-Japan Union Hospital,Jilin University,Changchun 130033,China;2.Department of Internal Medicine,No. 461 Hospital of PLA,Changchun 130021,China;3.Department of Cardiovascular Diseases,General Hospital of Shenyang Military District,Shenyang 110015,China;4. Department of Regenerative Medicine,Institute of Frontier Medical Sciences,Jilin University,Changchun 130021,China
  • Received:2013-10-17 Online:2014-05-28 Published:2014-06-05

摘要:

目的:构建高效分泌表达重组人淀粉样蛋白前体Kunitz型蛋白酶抑制剂结构域变异体(rhKD/APPvar)的毕氏酵母工程菌,建立适合大规模发酵、纯化rhKD/APPvar的工艺。方法:利用已构建的rhKD/APP表达质粒,在其活性中心两侧设计2个酶切位点(ApaⅠ和SacⅡ),实现人KD/APP活性中心RAM与BPTI活性中心KAR的替换,构建rhKD/APPvar表达质粒。将重组质粒转化到酵母菌X-33中,优化rhKD/APPvar表达最佳pH值,使rhKD/APPvar获得高效表达。利用阳离子交换树脂和超滤除盐对重组蛋白进行纯化。结果:酶切鉴定和测序分析显示成功构建了KD/APPvar-pPICZαC重组质粒。经电转化成功地将重组质粒转化至酵母菌X-33中。SDS-PAGE分析,甲醇诱导表达后在相对分子质量约6 700处出现蛋白条带,pH 6.0、甲醇诱导 120 h蛋白表达水平最高,经纯化获得纯度达95%的重组蛋白。结论:成功构建KD/APPvar- pPICZαC重组质粒,经毕赤酵母表达和纯化获得了rhKD/APPvar蛋白。

关键词: 毕赤酵母菌, 重组KD/APP变异体, 牛胰蛋白酶抑制剂, 淀粉样蛋白前体

Abstract:

Abstract:Objective To construct the engineering bacteria expressing the  recombinant human Kunitz protease inhibitor domain of amyloid protein precursor variant (rhKD/APPvar) in Pichia pastoris, and to establish the methods suitable for large-scale fermentation and purification of rhKD/APPvar. Methods The rhKD/APPvar expression vector was constructed based on the rhKD/APPvar-pPICZα  expression vector.Two restriction  enzyme loci (ApaⅠ and SacⅡ) were added to two flanks of KD/APP and human KD/APP activity center RAM was replaced by the active site of BPTI KAR. After the rhKD/APPvar-pPICZα expression vector was transformed into Pichia pastoris,optimized expression and purification of rhKD/APPvar was performed.The  rhKD/APPvar was purified with  cation exchange chromatography and desalting. Results The results of digestion identification and  DNA sequencing analysis  demonstrated that the recombinant plasmid rhKD/APPvar-pPICZα was successfully  constructed and transfected into pastoris X-33.The SDS-PAGE analysis results indicated that rhKD/APPvar expressed after the induction of methanol and the relative molecular weight was 6 700. After a series of experiments the optimal expression conditions of rhKD/APPvar were obtained as follows: the optimal pH was 6.0 and the optimal induction time point was about the 5th day for the strain. After purified the purity of rhKD/APPvar was about 95%. Conclusion KD/APPvar-pPICZ is successfully constructed; after expression in Pichia pastoris and purification,the  rhKD/APPvar protein is  obtained.

Key words: Pichia , pastoris;rhKD/APPvar;bovine pancreatic trypsin inhibitor;amyloid protein precursor

中图分类号: 

  • Q78