Journal
JOURNAL OF AGRICULTURAL AND FOOD CHEMISTRY
Volume 67, Issue 5, Pages 1478-1483Publisher
AMER CHEMICAL SOC
DOI: 10.1021/acs.jafc.8b06496
Keywords
5-aminolevulinic acid; chemically induced chromosomal evolution; fermentation optimization; adaptative evolution; plasmid-free strain
Funding
- National Natural Science Foundation of China [31670047, 31770095]
- Shandong Science and Technology Development Plan [2017GSF21121, 2017GSF21108]
- Natural Science Foundation of Shandong Province-Major Basic Research Project [ZR2017ZB0210]
Ask authors/readers for more resources
5-Aminolevulinic acid (5-ALA) is a key metabolic intermediate of the heme biosynthesis pathway, which has broad application prospects in agriculture and medicine. However, segregational instability of plasmid-based expression systems and low yield have hampered large-scale manufacture of 5-ALA. In this study, two important genes of the 5-ALA CS biosynthesis pathway, hemA and hemL, were integrated into Escherichia coli MG1655 for chemically induced chromosomal evolution (CIChE). The highest hemA and hemL copy-number, 98 per genome, was obtained in CIChE strain MG136. The 5-ALA titer of this strain reached 2724 mg/L in optimized condition. Then, after undergoing adaptative evolution and the deletion of recA, strain MG136a Delta recA::FRT could stably produce 4550 mg/L 5-ALA from glucose, 450 times the amount produced by hemA-hemL single copy strain MG1655-hemAL. This study constructed a plasmid-free E. coli strain for 5-ALA production, which will provide the basis for further manipulation of metabolic regulation and optimization of fermentation.
Authors
I am an author on this paper
Click your name to claim this paper and add it to your profile.
Reviews
Recommended
No Data Available