通过Escherichia coli的多维工程从葡萄糖中有效发酵生产β-Alanine
Yufei Zhang1,2, Guoyan Zhang1,2, Huifang Zhang2
1School of Life Sciences, Guangzhou University, 230 Wai Huan Xi Road, Guangzhou 510006, Guangdong, P. R. China.
Journal of agricultural and food chemistry
|June 13, 2024
概括
在工程Escherichia coli中实现了β-alanine (一种有价值的氨基酸) 的可持续生物合成. 系统代谢工程显著提高了β-氨酸的产量,通过优化前体供应,基因表达和运输达到74.03g/L.
科学领域:
- 生物技术是生物技术.
- 代谢工程是代谢工程.
- 微生物菌株的发展
背景情况:
- β-氨酸是一种关键的氨基酸,具有多种工业应用,包括食品,补充剂和药品.
- 目前的可持续生物合成方法面临着局限性,因为在菌株强度和基因操纵方面存在挑战.
- 开发高效的微生物细胞工厂对于满足日益增长的β-氨酸需求至关重要.
研究的目的:
- 为了改造大肠杆菌以增强β-氨酸的可持续生物合成.
- 通过系统代谢工程,克服当前β-氨酸生产方法的局限性.
- 为了实现高度,高产量的β-氨酸生产,使用一个具有成本效益的介质.
主要方法:
- 招募一个高效的l-酸-α-脱碳酶 (ADC) 来合成β-氨酸.
- 通过使转移酶系统 (PTS) 失活并引入非PTS系统来修改葡萄糖同化系统.
- 优化前体供应,ADC表达 (促进器和UTR工程) 和运输 (破坏进口商CycA,表达出口商NCgI0580).
- 开发一种成本效益高的介质,使用玉米液进行料批发发酵.
主要成果:
- 在修改了葡萄糖同化系统后,初始β-氨酸的产量达到1.70g/L.
- 通过协同改善前体供应 (氧酸盐和l-酸盐) 的作用,滴量增加到3.43g/L.
- 进一步的工程,包括运输优化,将产量提高到8.48g/L.
- 最终的工程菌株产生了74.03g/L的β-氨酸,其产量为0.57mol/mol的葡萄糖,使用成本高效的介质.
结论:
- 系统代谢工程有效地增强了埃舍里希亚大肠杆菌中的β-氨酸生物合成.
- 优化前体供应,基因表达和运输机制对于高度生产至关重要.
- 开发的菌株和工艺证明了可持续的β-氨酸制造的可行性和成本效益的方法.
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