双促进体系统通过产生基拉尼的大肠杆菌中的非翻译负担驱动等离子体损失
Jia Zhou1, Mengqi Cheng1, Shengyang Su1
1Faculty of Life Science and Food Engineering, HuaiYin Institute of Technology, Huaian, 223003, PR China.
Archives of microbiology
|December 9, 2025
概括
在等离子体上强大的促进剂通过增加转录应激而不是蛋白质生产负担,导致工程化大肠杆菌 (大肠杆菌) 的不稳定. 这影响了工业类制造业.
科学领域:
- 合成生物学 合成生物学
- 代谢工程是代谢工程.
- 微生物生物技术 微生物生物技术
背景情况:
- 在大肠杆菌中以等离子体为基础的代谢负担是工业化物生产的主要障碍.
- 导致等离子体不稳定的转录应激的精确分子原因尚未完全理解.
研究的目的:
- 区分转录和转化对工程化大肠杆菌等离子体不稳定性的贡献.
- 为了研究促进体结构对在化物生产过程中的代谢负担和质粒稳定性的影响.
主要方法:
- 工程化大肠杆菌菌株与具有多种促进体设计 (Trc与T7,单与双促进体) 的同源塑.
- 在不同的促进物条件下,量化基拉尼标位,细胞生长率和等离子体保留.
- 利用删除核糖体结合部位/多重克隆部位 (RBS/MCS) 来隔离转录负担.
主要成果:
- 双促进体系统导致了显著的生产失败 (92.1% - 94.8%的标位降低) 和生长抑制 (34.6 - 37.9%).
- 在RBS/MCS删除后,超过53%的代谢负担仍然存在,这证实了转录启动是主要原因.
- 与Trc促进剂 (80.0%) 相比,更强的双T7促进剂大大降低了等离子体稳定性 (至45.0%).
结论:
- 等离子体的不稳定性主要是由转录启动的负担驱动的,与转化成本不同,特别是在强大的促进剂中.
- 宿主适应部分恢复生长,但不能恢复代谢流量,这表明不可逆转的失衡.
- 结果指导促进物选择,以稳定微生物生产类和其他有价值的化合物.
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