食品科学 ›› 2008, Vol. 29 ›› Issue (7): 267-271.

• 生物工程 • 上一篇    下一篇

水稻密码子优化的cry2A*基因在大肠杆菌中的表达及其表达产物的纯化

秦伟,黄昆仑,贺晓云,李欣,许文涛,林希瑾,罗云波   

  1. 中国农业大学食品科学与营养工程学院食品生物技术实验室; 中国农业大学食品科学与营养工程学院食品生物技术实验室 北京100083; 北京100083
  • 出版日期:2008-07-15 发布日期:2011-07-28

Expression of Rice Codon Optimized cry2A* Gene in Escherichia coli and Purification of Its Expressed Proteins

QIN  Wei, HUANG  Kun-Lun, HE  Xiao-Yun, LI  Xin, XU  Wen-Tao, LIN  Xi-Jin, LUO  Yun-Bo   

  1. Laboratory of Food Biotechnology, College of Food Science and Nutritional Engineering, China Agricultural University, Beijing 100083, China
  • Online:2008-07-15 Published:2011-07-28

摘要: 通过PCR从克隆载体pUC18-3Z/Cry2A*上扩增水稻偏爱型密码子优化的抗虫基因cry2A*,经限制性内切酶NdeI和BamHI双酶切定向插入到原核表达载体pET-28a(+),成功构建了在表达蛋白的N端只带有6个组氨酸标签的融合蛋白表达载体pET-28a(+)/Cry2A*,并转入大肠杆菌BL21(DE3)中。通过对其表达条件进行优化,发现在IPTG浓度为0.05mmol/L、诱导时间为3h、诱导温度为20℃的表达条件下目的蛋白大部分以可溶形式进行表达。采用Ni-NTA亲和柱纯化得到高纯度目的蛋白,薄层扫描分析蛋白纯度达到95%。

关键词: 抗虫基因, cry2A*, 转基因水稻, 表达, 纯化

Abstract: The coding sequence of rice preferable codon optimized cry2A* gene was amplified via polymerase chain reaction (PCR) from recombinant plasmid pUC18-3Z/Cry2A*. Then the PCR products of cry2A* gene were inserted into expression vector pET-28a(+) using restriction endonucleases Nde I and BamH I, resulting in the recombinant expression plasmid pET-28a(+)/ Cry2A* expressing Cry2A* proteins with only 6 His-tags attached to its N-terminus. Subsequently, the expression vector pET-28a(+)/Cry2A* was introduced into E. coli BL21 (DE3). The Cry2A* protein was expressed mainly in soluble form in the presence of isopropyl-β-D-thiogalactopyranoside (IPTG) with final concentration 0.05 mmol/L by inducing for 3 h at 20 ℃. The recombinant protein was purified by Ni-NTA affinity chromatography, and the purity is up to 95% according to thin layer scanning analysis.

Key words: insecticidal gene, cry2A*, transgenic rice, expression, purification