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• 基础研究 • 上一篇    下一篇

rhKPI/AβPP大规模发酵及纯化工艺

贺巾超1,杨莉莉1,马 杰1,颜波群2,韩树海1,侯立中1,颜炜群1*   

  1. 1. 吉林大学再生医学科学研究所生物化学研究室,吉林 长春130021;2. 吉林大学第四医院消化内科,吉林 长春130011
  • 收稿日期:2005-09-12 修回日期:1900-01-01 出版日期:2006-03-28 发布日期:2006-03-28
  • 通讯作者: 颜炜群1*

Large scale fermentation process and purification for rhKPI/AβPP in Pichia pastoris

HE Jin-chao1, YANG Li-li1, MA Jie1, YAN Bo-qun2 ,HAN Shu-hai1,HOU Li-zhong1,YAN Wei-qun1*   

  1. 1. Department of Biochemistry, Institute of Frontier Medical Sciences, Jilin University, Changchun 130021,China;2. Department of Digestive Medicine,Fourth Hospital,Jilin University, Changchun 130011,China
  • Received:2005-09-12 Revised:1900-01-01 Online:2006-03-28 Published:2006-03-28
  • Contact: YAN Wei-qun1*

摘要: 目的:在毕赤酵母(Pichia pastoris)中高效表达AβPP中的Kunitz型蛋白酶抑制剂的结构域(KPI/AβPP),利用80 L的发酵罐优化发酵条件,制备rhKPI/AβPP。方法:克隆kpi基因插入到pPICZα,构建真核表达载体pPICZα-kpi,经核酸测序确证后,电转化毕赤酵母菌株X-33,筛选高表达rhKPI/AβPP工程菌。结果:筛选出的高表达工程菌采用80L发酵罐甲醇诱导补料批式发酵,在pH 3.3、纯氧浓度22%~30%、罐内压力为12psi、甲醇诱导60 h时产量1.0 g·L-1。纯化的rhKPI/AβPP经SDS-PAGE分析显示单一区带,相对分子质量6 750。质谱测定其相对分子质量为6 750,抑制胰蛋白酶的比活性为8.4 EPU·mg-1。结论:克隆、构建、筛选出高效表达rhKPI/AβPP的毕赤酵母工程菌,并建立了稳定的发酵和纯化工艺。

关键词: AβPP, 毕赤酵母, 发酵

Abstract: Objective To study the efficient expression of a Kunitz-type protease inhibitor(KPI) domain of the Alzheimer′s disease related to amyloid β-protein precursor, and produce rhKPI/AβPP by optimizing fermentation papameters on large scale using Pichia pastoris as host system. Methods KPI/AβPP gene was inserted into expression vector pPICZα and the resulted recombinant vector was transformed into the Pichia pastoris. Then KPI/AβPP was expressed in 80L fermentor with optimizing parameters and the broth was harvested and purified with SP Sepharose. Results KPI/AβPP gene could be induced by methanol and expressed with the maximal yield of 1.0 g·L-1. The expressed product was purified from the fermentating culture. Analytic results revealed that resulted product with relative molecular mass of about 6 750 inhibited the serine protease activities. Conclusion rhKPI/AβPP can be expressed in Pichia pastoris on large scal. A stable fermentation and purification technology is successfully set up.

Key words: AβPP , Pichia, fermentation

中图分类号: 

  • Q78