多变量模块化代谢工程和媒介优化,以维生素B12由大肠杆菌生产
Feitao Chen1,2, Huan Fang2,3,4,5, Jianghua Zhao2,3
1College of Biotechnology, Tianjin University of Science & Technology, Tianjin, 300457, China.
Synthetic and systems biotechnology
|April 18, 2024
概括
这项研究使用代谢工程增强了大肠杆菌中维生素B12的产生. 用酵母粉进行优化发酵,达到创纪录的2.89mg/L标位,为工业规模的维生素B12 (胺) 制造铺平了道路.
科学领域:
- 生物技术是生物技术.
- 代谢工程是代谢工程.
- 微生物发酵 微生物发酵
背景情况:
- 工业维生素B12 (科巴胺) 的生产依赖于微生物发酵.
- 大肠杆菌 (E. coli) 可以被设计为新的维生素B12生物合成,但面临代谢限制.
- 在微生物宿主中优化复杂的生物合成途径对于高效的生产至关重要.
研究的目的:
- 通过多变量模块化代谢工程来增强大肠杆菌中维生素B12的产生.
- 确定最佳的遗传模块和促进剂组合,以增加维生素B12标位.
- 改善发酵条件,以最大限度地提高维生素B12的产量.
主要方法:
- 在大肠杆菌中设计了维生素B12生物合成途径的两个模块 (10个基因).
- 在染色体中使用T7,J23119和J23106促进体进行组合优化.
- 用酵母粉补充发酵介质,并在5升发酵器中扩大生产规模.
主要成果:
- 使用J23119和T7促进剂的组合途径优化产生了最高的维生素B12标位.
- 酵母粉补充剂通过增强氧气转移和IPTG耐受性,将维生素B12标位提高到1.52 mg/L.
- 经过扩大规模的发酵,最终的维生素B12标位达到2.89 mg/L.
结论:
- 多变量模块化代谢工程有效地增强了大肠杆菌中维生素B12的产生.
- 优化发酵介质和扩大规模对于工业可行性至关重要.
- 开发的战略加速了以大肠杆菌为基础的工业规模维生素B12生产的发展.
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