从果糖中有效地生产2'-糖,通过代谢工程重组Escherichia coli
Ran You1,2, Lei Wang3,4, Meirong Hu2
1Division of Life Sciences and Medicine, University of Science and Technology of China, Hefei, 230027, China.
Microbial cell factories
|February 2, 2024
概括
大肠杆菌的新陈代谢工程从果糖中获得了2'-fucosyllactose (2'-FL),一种关键的人类牛奶寡糖的高静态度产量. 这种微生物生产克服了工业应用化学合成的局限性.
科学领域:
- 生物技术是生物技术.
- 代谢工程是代谢工程.
- 微生物合成 微生物合成
背景情况:
- 人类牛奶寡糖 (HMO) 在制药和食品中具有价值.
- 2 -最丰富的HMO - - 糖乳糖 (2 -FL) 很难通过化学合成生产.
- 目前在大肠杆菌中,微生物对2-FL的产生受到低静态度产量的影响.
研究的目的:
- 开发一种由代谢工程设计的大肠杆菌菌株,用于从果糖中产生2-FL的高产生物合成.
- 优化2 -FL生物合成途径并增强碳流量,以提高工业可行性.
主要方法:
- 设计了一种新的2-FL生物合成途径,利用五种关键酶.
- 通过删除特定的基因 (pfkA, pfkB, pgi) 和修改促销器区域来改造大肠杆菌.
- 优化了共表达系统,并选了多个fucosyltransferase (FucT) 变体.
- 调节了gapA基因,进一步促进了2-FL的产生.
主要成果:
- 获得了0.5mol2 -FL/mol果糖的理论静态度收益率.
- 工程化大肠杆菌菌株RFL38表现出0.498mol2 -FL/mol果糖的最高体内测量产量.
- 扩大的料批生物转化产生了41.6 g/L (85.2 mM) 的2 -FL.
- 在缩放反应中获得的高产量:0.482 mol 2 -FL/mol果糖和0.986 mol 2 -FL/mol乳糖.
结论:
- 在大肠杆菌中使用代谢工程成功优化了2-FL生物合成.
- 从果糖中生物制造2-FL的首次演示,具有较高的固体测量产量.
- 为引导碳流向2-FL合成和糖解提供了宝贵的参考.
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