细胞生长阶段依赖的促进剂替代方法,以改善大肠杆菌中的聚乳酸-co-3-hydroxybutyrate) 生产
Yuki Nagao1, Sangho Koh2, Seiichi Taguchi2,3
1School of Agriculture, Meiji University, 1-1-1 Kawasaki-Shi, Kanagawa, 214-8571, Japan.
Microbial cell factories
|July 19, 2023
概括
在大肠杆菌中优化基因表达增强了聚[LA-co-3HB]的产生. 选择特定的促进剂和碳来源可以显著提高聚产量和乳酸盐含量.
科学领域:
- 合成生物学 合成生物学
- 代谢工程是代谢工程.
- 聚合物科学 聚合物科学
背景情况:
- 大肠杆菌 (Escherichia coli) 作为一种多功能宿主,可以通过合成生物学生产有价值的材料.
- 聚[乳酸盐-co-3-基酸盐] (P(LA-co-3HB)) 的生产涉及来自多种生物的基因.
研究的目的:
- 为了优化基因表达时间和水平,在大肠杆菌中增强P ((LA-co-3HB) 生产.
- 通过促进体替换来操纵聚内部的乳酸盐 (LA) 分数.
主要方法:
- 工程化大肠杆菌菌株表达P ((LA-co-3HB) 合成的异质基因.
- 用21种不同的促进剂系统地替换原生促进剂以控制基因表达.
- 在LB介质中进行培养,并补充葡萄糖或糖以评估促进剂效应.
主要成果:
- C1STQK-AB操作子对于静止阶段P(LA-co-3HB) 生产至关重要.
- 促进体选择显著影响了生产和LA分数,dps和yliH促进体分别在葡萄糖和西洛斯介质中表现出最佳结果.
- 在葡萄糖介质中,dps促进剂增加了积累到8.8 g/L (14.1 mol% LA);在西介质中,yliH增加了产量到5.6 g/L (40.2 mol% LA).
结论:
- 对于phaC1STQK-AB操作子的战略促进物选择是提高P(LA-co-3HB) 产量和LA含量的关键.
- 细胞生长阶段依赖的促进剂与适当的碳来源相结合,为细胞内聚生产提供了一种多功能策略.
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