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›› 2013, Vol. 13 ›› Issue (6): 1013-1019.

• 生化工程专栏 • 上一篇    下一篇

代谢工程改造蛋氨酸代谢途径构建高产L-蛋氨酸大肠杆菌

郭谦 方芳 李江华 陈坚 堵国成   

  1. 江南大学工业生物技术教育部重点实验室 江南大学生物工程学院环境生物技术研究室 江南大学生物工程学院 江南大学工业生物技术教育部重点实验室 江南大学工业生物技术教育部重点实验室
  • 收稿日期:2013-09-30 修回日期:2013-11-13 出版日期:2013-12-20 发布日期:2013-12-20
  • 通讯作者: 李江华

Metabolic Engineering of Methionine Biosynthesis Pathway for Production of L-Methionine by Escherichia coli

GUO Qian FANG Fang LI Jiang-hua CHEN Jian, DU GUo-cheng,   

  1. Key Laboratory of Industrial Biotechnology, Ministry of Education, Jiangnan University Lab. Envionmntal Biotech., School of Biotech., Southern Yangtze University School of Biotechnology, Southern Yangtze University Key Lab. Industrial Biotechnol., Ministry of Education, Jiangnan University Lab of Environmental Biotechnology, School of biotechnology Southern Yangtze University
  • Received:2013-09-30 Revised:2013-11-13 Online:2013-12-20 Published:2013-12-20
  • Contact: LI Jiang-hua

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被引次数

3

摘要： 以Escherichia coli BL21(DE3)为出发菌株，敲除其蛋氨酸合成途径中关键酶的阻遏基因metJ，使菌株积累蛋氨酸达22 mg/L. 在此基础上，利用紫外诱变筛选育出一株抗蛋氨酸结构类似物的蛋氨酸高产菌株YB12，使蛋氨酸产量提高到60 mg/L. 通过过量表达蛋氨酸合成途径中的metA和cysE基因及编码蛋氨酸转运蛋白的yeaS基因，YB12菌株积累蛋氨酸量提高到251 mg/L. 结果表明，蛋氨酸在胞外的积累受多个基因、多种代谢途径调控，单独敲除某个基因或改造某个途径不能使蛋氨酸大量合成和积累，对多个代谢途径共同改造是构建蛋氨酸工程菌的最有效方法.

关键词: 大肠杆菌, 蛋氨酸, 突变, metJ, 过量表达

Abstract: Escherichia coli BL21(DE3) strains that can overproduce methionine were constructed by regulating the methionine biosynthesis pathway. Knocking out metJ, a gene encoding the methionine biosynthesis repressor, demonstrated the initial accumulation of methionine (22 mg/L) by E. coli BL21(DE3). L-methionine yield was then increased to 60 mg/L by selection of methionine analogue resistant YB12 using the ultraviolet mutagenesis. Furthermore, over-expression of methionine biosynthesis key genes metA, cysE and yeaS in YB12 dramatically enhanced the production of methionine by E. coli strains (251 mg/L). These results indicated that the combination of gene modification and gene regulation in methionine biosynthesis pathway was required to achieve the high accumulation of methionine or the construction of met-excreting strains.

Key words: Escherichia coli, methionine, mutagenesis, metJ, over-expression

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