通过代谢工程改善Bacillus subtilis 168中的表面素生产
Zihao Guo1, Jiuyu Sun1, Qinyuan Ma1
1School of Life Sciences and Medicine, Shandong University of Technology, 266 Xincun West Road, Zibo 255049, China.
Microorganisms
|May 25, 2024
概括
工程 Bacillus subtilis 168 产生表面活性素,一种有价值的生物表面活性剂. 过度表达sfp*基因和淘汰codY基因显著提高了工业应用的表面素产量.
科学领域:
- 微生物学 微生物学
- 生物技术是生物技术.
- 代谢工程是代谢工程.
背景情况:
- 表面活性是一种强大的生物表面活性剂,具有多种工业应用.
- 野生类型的 Bacillus subtilis 168 缺乏合成表面因子的能力.
- 需要基因工程策略来建立高效的表面蛋白生产.
研究的目的:
- 为了改造Bacillus subtilis 168以提高表面素的生产.
- 研究特定基因在表面素生物合成和运输中的作用.
- 为了优化发酵条件,以生产高产的表面素.
主要方法:
- 过度表达的酸乙烯转移酶 (PPTase) 基因sfp*.
- 基因淘汰策略的目标是ppsD,yvkC和codY.
- 表面素载体基因 (yfiS,yerP,ycxA) 的过度表达.
- 在5L发酵器中使用料批培养的发酵优化.
主要成果:
- 在B. subtilis 168中通过sfp*过度表达 (747.5 mg/L) 恢复了表面素合成.
- 确定了YfiS作为潜在的表面因子流量输送器.
- 通过淘汰 codY 基因,通过淘汰 codY 基因,实现显著增强的表面素标位 (1601.8 mg/L).
- 达到3.89g/L的最大表面素值,产量为0.63g/g的DCW.
结论:
- 成功设计了B. subtilis 168用于高产量的表面素生产.
- CodY 是表面素合成的关键负调节剂.
- 工程菌株为工业表面膜制造提供了一个强大的平台.
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