SCI和EI收录∣中国化工学会会刊

Chin.J.Chem.Eng. ›› 2015, Vol. 23 ›› Issue (11): 1834-1839.DOI: 10.1016/j.cjche.2015.08.013

• BIOTECHNOLOGY AND BIOENGINEERING • Previous Articles     Next Articles

Improvement of the riboflavin production by engineering the precursor biosynthesis pathways in Escherichia coli

Zhibo Xu1, Zhenquan Lin1, Zhiwen Wang2, Tao Chen3   

  1. 1 Key Laboratory of Systems Bioengineering (Ministry of Education), Tianjin University, Tianjin 300072, China;
    2 SynBio Research Platform, Collaborative Innovation Center of Chemical Science and Engineering (Tianjin), School of Chemical Engineering and Technology, Tianjin University, Tianjin 300072, China;
    3 Edinburg-Tianjin Joint Research Centre for Systems Biology and Synthetic Biology, Tianjin University, Tianjin 300072, China
  • Received:2014-05-23 Revised:2014-11-06 Online:2015-12-18 Published:2015-11-28
  • Contact: Tao Chen

Improvement of the riboflavin production by engineering the precursor biosynthesis pathways in Escherichia coli

Zhibo Xu1, Zhenquan Lin1, Zhiwen Wang2, Tao Chen3   

  1. 1 Key Laboratory of Systems Bioengineering (Ministry of Education), Tianjin University, Tianjin 300072, China;
    2 SynBio Research Platform, Collaborative Innovation Center of Chemical Science and Engineering (Tianjin), School of Chemical Engineering and Technology, Tianjin University, Tianjin 300072, China;
    3 Edinburg-Tianjin Joint Research Centre for Systems Biology and Synthetic Biology, Tianjin University, Tianjin 300072, China
  • 通讯作者: Tao Chen

Abstract: 3,4-Dihydroxy-2-butanone 4-phosphate (DHBP) and GTP are the precursors for riboflavin biosynthesis. In this research, improving the precursor supply for riboflavin production was attempted by overexpressing ribB and engineering purine pathway in a riboflavin-producing Escherichia coli strain. Initially, ribB gene was overexpressed to increase the flux from ribulose 5-phosphate (Ru-5-P) to DHBP. Then ndk and gmk genes were overexpressed to enhance GTP supply. Subsequently, a R419Lmutationwas introduced into purA to reduce the flux from IMP to AMP. Finally, co-overexpression of mutant purF and prs genes further increased riboflavin production. The final strain RF18S produced 387.6 mg riboflavin·L-1 with a yield of 44.8 mg riboflavin per gram glucose in shake-flask fermentations. The final titer and yield were 72.2% and 55.6% higher than those of RF01S, respectively. It was concluded that simultaneously engineering the DHBP synthase and GTP biosynthetic pathway by rational metabolic engineering can efficiently boost riboflavin production in E. coli.

Key words: Escherichia coli, Riboflavin, 3,4-Dihydroxy-2-butanone 4-phosphate, synthase, Purine pathway, GTP, Metabolic engineering

摘要: 3,4-Dihydroxy-2-butanone 4-phosphate (DHBP) and GTP are the precursors for riboflavin biosynthesis. In this research, improving the precursor supply for riboflavin production was attempted by overexpressing ribB and engineering purine pathway in a riboflavin-producing Escherichia coli strain. Initially, ribB gene was overexpressed to increase the flux from ribulose 5-phosphate (Ru-5-P) to DHBP. Then ndk and gmk genes were overexpressed to enhance GTP supply. Subsequently, a R419Lmutationwas introduced into purA to reduce the flux from IMP to AMP. Finally, co-overexpression of mutant purF and prs genes further increased riboflavin production. The final strain RF18S produced 387.6 mg riboflavin·L-1 with a yield of 44.8 mg riboflavin per gram glucose in shake-flask fermentations. The final titer and yield were 72.2% and 55.6% higher than those of RF01S, respectively. It was concluded that simultaneously engineering the DHBP synthase and GTP biosynthetic pathway by rational metabolic engineering can efficiently boost riboflavin production in E. coli.

关键词: Escherichia coli, Riboflavin, 3, 4-Dihydroxy-2-butanone 4-phosphate, synthase, Purine pathway, GTP, Metabolic engineering