通过使用大肠杆菌的系统工程,高效地生产protocatechuic酸
Ming Wang1, Haomiao Wang1, Cong Gao1
1School of Biotechnology and Key Laboratory of Industrial Biotechnology of Ministry of Education, Jiangnan University, Wuxi, 214122, China.
Metabolic engineering
|February 18, 2024
概括
这项研究设计了大肠杆菌,通过克服酶抑制和细胞毒性,有效地产生原酸 (PCA). 开发的菌株达到创纪录的PCA标位46.65g/L,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.
- 酶工程是什么? 酶工程是什么?
背景情况:
- 甲基甲酸 (PCA) 具有广泛的应用,但其高效的微生物生产受到3 - 脱基胺脱水酶 (AroZ) 抑制和PCA毒性的阻碍.
- 大肠杆菌是微生物生产的常见宿主,但需要工程来克服PCA生物合成的局限性.
研究的目的:
- 在大肠杆菌 (Escherichia coli) 中开发一种高位的原卡特丘酸 (PCA) 生产菌株.
- 阐明3-dehydroshikimate dehydratase (AroZ) 的结构功能关系,并将其设计为减少产品抑制.
- 提高细胞对PCA的耐受性,并建立有效的查方法,以改善生产菌株.
主要方法:
- 通过阻断碳流来制造工程化大肠杆菌,以创建3 - 脱石基胺过度产生的菌株 (DHS01).
- 引入了一种高活性的Acinetobacter pittii AroZ (ApAroZ),并设计了一个变体 (ApAroZR363A) 来缓解产品抑制.
- 通过适应性实验室进化提高了对PCA的抗菌株耐受性,并开发了一种生物传感器辅助的高通量选方法.
主要成果:
- 在5L生物反应器中,最终PCA标位达到46.65g/L,产量为0.23g/g,生产率为1.46g/L/h.
- 成功阐明了ApAroZ的结构和催化机制,从而产生了一种具有缓解产品抑制的工程变体.
- 开发了一种强大的大肠杆菌菌株 (PCA05),能够从葡萄糖中产生高水平的PCA.
结论:
- 工程化大肠杆菌菌株PCA05代表了微生物PCA生产的重大进步.
- 使用的策略,包括酶工程和适应性进化,适用于生产其他高价值的有毒化合物.
- 这项工作为PCA和相关化学品的工业规模生物合成提供了有价值的框架.
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