生物技术通报 ›› 2015, Vol. 31 ›› Issue (5): 93-99.doi: 10.13560/j.cnki.biotech.bull.1985.2015.05.015

• 研究报告 • 上一篇    下一篇

高粱SbGABA-Ts基因的克隆、原核表达及纯化

杨泽伟1,2, 王龙海1,2, 朱莉2, 汪海2, 黄大昉2, 郎志宏2   

  1. (1.西南科技大学生命科学与工程学院,绵阳 621010;2.中国农业科学院生物技术研究所,北京 100081)
  • 收稿日期:2015-01-29 出版日期:2015-05-18 发布日期:2015-05-18
  • 作者简介:杨泽伟,男,硕士研究生,研究方向:植物抗逆机理;E-mail:yangzewei555@sina.com
  • 基金资助:
    国家自然科学基金项目(31271790,31471558)

Cloning,Prokaryotic Expression of Sorghum bicolor SbGABA-Ts

Yang Zewei1,2, Wang Longhai1,2, Zhu Li2, Wang Hai2, Huang Dafang2, Lang Zhihong2   

  1. (1. Southwest University of Science and Technology,School of Life Science and Engineering,Mianyang 621010;2. Biotechnology Research Institute,Chinese Academy of Agricultural Sciences,Beijing 100081)
  • Received:2015-01-29 Published:2015-05-18 Online:2015-05-18

摘要: 植物中GABA(γ-氨基丁酸)代谢与植物生长发育、信号传递及逆境响应等过程密切相关,而参与GABA代谢的关键酶GABA-T(γ-氨基丁酸转氨酶)在重要农艺作物中的研究相对滞后。利用同源性分析在高粱基因组数据库中获得两个γ-氨基丁酸转氨酶(SbGABA-T)基因,RT-PCR方法进行基因克隆,并连入原核表达载体pET28a(+),转化E. coli BL21(DE3)进行基因异源表达分析。结果表明,包含SbGABA-T编码区全长的融合蛋白主要在包涵体中表达,而去除了SbGABA-T N端信号肽的融合蛋白以部分可溶的形式存在。进一步优化表达条件,IPTG浓度为1 mmol/L时,16℃低温诱导18 h,即可获得大量可溶性融合蛋白。用带His标签的镍柱对融合蛋白进行了纯化。

关键词: 高粱GABA-T, 原核表达, 纯化, 信号肽

Abstract: GABA is a ubiquitous four-carbon,non-protein amino acid,and has been associated with growth and development,signaling transduction,and stress response in plants. GABA transaminase(GABA-T),the enzyme responsible for the catabolism of GABA,has not been fully explored,especially in several important crops. Two putative GABA transaminase genes(GABA-T)from Sorghum bicolor were obtained based on homology analysis with the identified GABA-Ts of other plants and RT-PCR. Subsequently,the two SbGABA-T genes and corresponding N-terminal truncated SbGABA-Ts were inserted into pET28a(+)vector and individually imported into E. coli strain BL21(pLysS,DE3). Percentage improvement of soluble recombinant proteins were showed when removing the targeting peptide sequence of SbGABA-Ts. The fusion proteins were expressed partially in soluble form after incubating for 18 h at 16℃ by adding 1 mmol/L IPTG,and purified through nickel-affinity chromatography column.

Key words: Sorghum bicolor GABA-T, prokaryotic expression, purification, signal peptide