将定向进化与高细胞透性结合起来,在工程化大肠杆菌中产生高水平的尸体
Xuemei Liu1, Ruoshi Luo1, Dan Wang1
1Department of Chemical Engineering, School of Chemistry and Chemical Engineering, Chongqing University, Chongqing, P. R. China.
Biotechnology journal
|March 12, 2024
概括
这项研究设计了一个绿色细胞工厂,以促进尸体生物合成,以实现可持续的生物尼龙生产. 通过 lipopolysaccharide 基因调节提高细胞透性,显著增加了尸体产量,为工业应用铺平了道路.
科学领域:
- 生物技术和代谢工程 生物技术和代谢工程
- 工业微生物学 工业微生物学
- 可持续化学 可持续化学
背景情况:
- 从氨酸的尸体生物合成是生物尼龙5X前体的可持续途径.
- 目前的尸体位不足以用于工业规模的生物尼龙生产.
- 提高细胞透性对于提高生物转化效率至关重要.
研究的目的:
- 开发一个高效的"绿色细胞工厂"用于尸体生产.
- 通过改造脂多糖 (LPS) 基因和改善膜透性来增强尸体生物合成.
- 为了优化生产过程的工业可扩展性.
主要方法:
- 构建和选10个脂多糖 (LPS) 突变菌株的大肠杆菌.
- 氨酸脱碳酶 (CadA) 的过度表达和定向进化,以改善酶稳定性.
- 优化和扩大Feed-batch生物转化过程.
主要成果:
- 与对照组 (4,92 g/L) 相比,LPS突变菌株Cad02和Cad06显示出明显更高的尸体产量 (8.95 g/L和7.55 g/L).
- 定向进化产生了一种CadA突变 (Cad02-M),在pH值8.0时,该突变使尸体产量增加了1.86倍.
- 扩大规模使用重组完整细胞实现了211g/L尸体 (96.8%的产量) 的高标位.
结论:
- 调节LPS基因并增强细胞透性有效地提高了体内质量转移和尸生物合成酶的可访问性.
- 开发的方法为生产尸体和其他有价值的化学物质提供了一种普遍适用的,具有成本效益和环保的方法.
- 这家工程细胞工厂展示了生物基化学品可持续工业生产的巨大潜力.
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