在大肠杆菌中的新型FNR依赖氧气响应促进体:设计,表征和代谢工程应用
Sen Yang1, Wen-Yue Tong1, Chao-Hao Guo1
1Key Laboratory of Microbial Diversity Research and Application of Hebei Province, Institute of Life Science and Green Development, Hebei University, Baoding 071002, China.
ACS synthetic biology
|June 21, 2025
概括
研究人员在大肠杆菌中开发了新的氧气反应性促进体,用于代谢工程. 这些促进剂在不同氧气水平下提供动态基因控制,增强发酵过程中的酸盐生产.
科学领域:
- 微生物学 微生物学
- 代谢工程是代谢工程.
- 合成生物学 合成生物学
背景情况:
- 对于动态代谢工程来说,对氧反应的促进剂至关重要,特别是在有限氧的发酵中.
- 现有的依赖氧的促进剂具有有限的动态范围,缺乏负调节.
- 需要新的促进剂,这些促进剂可以根据溶解氧水平精确控制基因表达.
研究的目的:
- 在大肠杆菌 (Escherichia coli) 中设计和表征新型溶解的氧气反应性促进体.
- 为了开发厌氧激活和厌氧抑制的促进剂.
- 为了证明这些促进剂在增强酸盐生产中的实用性.
主要方法:
- 通过在核心促进器上游插入FNR结合位 (FBS) 来构建无氧激活促进器.
- 通过插入FBS下游或侧面的构成性促进剂,开发出无氧抑制的促进剂.
- 在DH5α Δfnr菌株中验证了促进体功能,并评估了对氧气耗尽的反应时间.
主要成果:
- 在无氧和有氧条件下实现了24-138倍高的激活促进体活性.
- 在无氧条件下,对抑制的促进体有8-17%的残留活性.
- 经过工程设计的大肠杆菌产生了5.76g/L的pyruvate,使用新型促进剂的产量为55.7%.
结论:
- 在大肠杆菌中成功设计和表征了一组由FNR调节的新型氧响应促进体.
- 这些促进体具有显著的动态范围,并通过溶解氧来实现精确的基因调节.
- 开发的促进剂为优化发酵过程提供了新的遗传工具,特别是在两阶段策略中.
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