[使用定数感应电路进行动态调节,可增强大肠杆菌 (Escherichia coli) 产生的醇]
Yuping Shen1,2, Ziwei Zhou1, Xi He1
1College of Chemistry and Bioengineering, Hunan University of Science and Engineering, Yongzhou 425199, Hunan, China.
Sheng wu gong cheng xue bao = Chinese journal of biotechnology
|August 25, 2023
概括
通过阻断竞争性途径并使用定数感应来降低毒性,工程 *Escherichia coli* 增强了铁醇生产. 这导致了醇产量和细胞密度的显著增加,为工业应用铺平了道路.
科学领域:
- 生物技术是生物技术.
- 代谢工程是代谢工程.
- 合成生物学 合成生物学
背景情况:
- 铁是一种有价值的天然多化合物,具有多种工业应用.
- 目前在大肠杆菌中*de novo*的铁醇合成面临挑战,包括细胞密度低和产量低.
- 之前的研究已经确定了一种酸脱碳酶突变体 (ARO10F138L/D218G) 用于铁生产.
研究的目的:
- 通过优化酶融合和代谢途径,增强大肠杆菌中的醇生物合成.
- 在工程微生物宿主中克服低细胞密度和铁醇毒性的局限性.
- 开发一个强大的和可扩展的发酵工艺,以增加醇的生产.
主要方法:
- 一个基酸脱碳酶突变体与各种酒精脱酶的融合表达,以创建最佳的融合蛋白.
- 基因淘汰*feaB*以消除竞争中的4-基酸路径.
- 实施一个定数感应电路,以动态调节醇合成途径,以减轻毒性.
主要成果:
- 最优的融合蛋白 ARO10F138L/D218G-L-YahK 实现了1.09 g/L 铁醇的产生.
- 淘汰 *feaB* 增加了 21.15% 的铁醇产量,达到 1.26 g/L.
- 定数感应动态调节提升了铁醇产量至1.74g/L,在2L发酵器中,达到4.22g/L,细胞密度提高 (OD600为42.88).
结论:
- 结合基因淘汰和定数感应动态调节,可显著增强*Escherichia coli*中的铁醇产量.
- 这一策略有效地解决了铁醇的毒性,并改善了细胞生长,从而提高了产量.
- 开发的方法对其他有毒化学化合物的生物合成具有前景.
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