African Journal of
Biotechnology

  • Abbreviation: Afr. J. Biotechnol.
  • Language: English
  • ISSN: 1684-5315
  • DOI: 10.5897/AJB
  • Start Year: 2002
  • Published Articles: 12184

Full Length Research Paper

Overexpression of key enzymes of the 2-C-methyl-D-erythritol-4-phosphate (MEP) pathway for improving squalene production in Escherichia coli

Haiyuan Liu
  • Haiyuan Liu
  • China State Institute of Pharmaceutical Industry, Zhangjiang Insitute, Shanghai 201203, China.
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Shu Han
  • Shu Han
  • China State Institute of Pharmaceutical Industry, Zhangjiang Insitute, Shanghai 201203, China.
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Liping Xie
  • Liping Xie
  • China State Institute of Pharmaceutical Industry, Zhangjiang Insitute, Shanghai 201203, China.
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Jie Pan
  • Jie Pan
  • China State Institute of Pharmaceutical Industry, Zhangjiang Insitute, Shanghai 201203, China.
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Wei Zhang
  • Wei Zhang
  • China State Institute of Pharmaceutical Industry, Zhangjiang Insitute, Shanghai 201203, China.
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Guihua Gong
  • Guihua Gong
  • China State Institute of Pharmaceutical Industry, Zhangjiang Insitute, Shanghai 201203, China.
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Youjia Hu
  • Youjia Hu
  • China State Institute of Pharmaceutical Industry, Zhangjiang Insitute, Shanghai 201203, China.
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  •  Received: 07 September 2017
  •  Accepted: 16 November 2017
  •  Published: 13 December 2017

Abstract

2-C-Methyl-D-erythritol-4-phosphate (MEP) pathway has been extensively employed for terpenoids biosynthesis in Escherichia coli. In this study, to obtain key-enzymes of MEP pathway for squalene production, overexpression of different combination of MEP pathway genes were compared. Squalene production in strain YSS12 with overexpressed dxs, idi and ispA of MEP pathway from E. coli was improved by 71-fold when compared with strain YSS3 which only contained double copy SQS. Analysis of transcriptional levels of MEP pathway genes in engineering strains showed that different squalene production can be attributed to changed transcriptional levels of co-overexpressed genes dxs, idi, ispG and ispA in engineering strains. Furthermore, different E. coli expression hosts were compared for squalene production, among which BL21(DE3) was the best squalene producer. These results illustrate that dxs, idi and ispA of the MEP pathway from E. coli were key-enzymes for squalene production in E. coli. These key-enzymes of MEP pathway could also be applied to other terpenoids production in E. coli.

 

Key words: Squalene, key-enzyme, 2-C-methyl-D-erythritol-4-phosphate (MEP) pathway, Escherichia coli.