系统工程Escherichia coli从葡萄糖中有效生产p-coumaric酸的系统工程
Chong Qiu1,2, Xiaoge Wang2, Jiaojiao Zuo1
1College of Bioscience and Biotechnology, Yangzhou University, Yangzhou, China.
Biotechnology and bioengineering
|April 26, 2024
概括
这项研究使大肠杆菌产生p-coumaric acid (p-CA),这是一个有价值的植物代谢物. 优化酶活性和提高NADPH水平显著增加了工业应用的p-CA产量.
科学领域:
- 代谢工程是代谢工程.
- 合成生物学 合成生物学
- 生物技术是生物技术.
背景情况:
- 酸 (p-CA) 是一种具有抗氧化和抗炎性能的植物代谢物,广泛用于生物医学,食品和化品.
- 由于酶表达和活性瓶,现有的p-CA生产方法面临限制.
研究的目的:
- 为了增强工程化大肠杆菌菌株的p-coumaric酸 (p-CA) 的产生.
- 克服在p-CA合成途径中AtC4H酶的低可溶性表达和活性的局限性.
- 增加细胞内NADPH水平以改善p-CA生物合成.
主要方法:
- 设计了一种合成途径 (PAL),将AtPAL2,AtC4H和AtATR2酶集成到大肠杆菌PHE05.05中.
- 通过N端修饰增强AtC4H的可溶性表达和活性,开发出一个最佳的突变AtC4HL373T/G211H.
- 采用了代谢工程策略,包括ppnk过度表达,以增加细胞内NADPH池和NADPH/NADP比率.
主要成果:
- 开发了一个最佳的AtC4H突变,kcat/Km值高4.3倍.
- 在工程化大肠杆菌PHCA20中,ppnk的过度表达导致NADPH含量增加了13.9倍,NADPH/NADP比率增加了1.3倍.
- 在5L发酵器中,p-CA标位增加了29.1%,达到3.09g/L,产量为20.01 mg/g葡萄糖,生产率为49.05 mg/L/h.
结论:
- 对AtC4H的N端修饰和促进NADPH的代谢工程是增强p-CA生产的有效策略.
- 工程化大肠杆菌菌株PHCA20显示了有效的工业规模生产p-coumaric酸的巨大潜力.
- 这项研究提出了一种新的方法,用于利用工业微生物菌株有效生物合成植物代谢物.
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