通过引入PHB调动通路来改善大肠杆菌的酸盐耐受性
Dong Meng1, Shuai Wang1, Ke Zhao2
1Key Laboratory of Medical Molecule Science and Pharmaceutical Engineering, Ministry of Industry and Information Technology, Institute of Biochemical Engineering, Department of Chemical Engineering, School of Chemistry and Chemical Engineering, Beijing Institute of Technology, Beijing, China.
Applied and environmental microbiology
|April 4, 2025
概括
聚β-基酸盐 (PHB) 调动通过改善膜完整性和功能,提高了Escherichia coli在酸压力下生存率. 这一过程还促进了从酸中酸盐和PHB的联合生产,提供了一个具有成本效益的微生物培养策略.
科学领域:
- 微生物学和生物技术
- 细菌生理学 细菌生理学
- 代谢工程是代谢工程.
背景情况:
- 聚β-基酸盐 (PHB) 是细菌的能量储备,对于在压力下生存至关重要.
- 酸是一种常见的工业副产品和微生物压力因素.
- 有效利用乙酸作为碳来源对于成本效益高的微生物过程至关重要.
研究的目的:
- 调查PHB动员在增强大肠杆菌对酸压力的耐受性方面的作用.
- 阐明PHB介导的酸耐药性的基础分子机制.
- 探索PHB调动在从酸盐中共同生产酸盐和PHB中的应用.
主要方法:
- 在乙酸压力下对野生型和PHB动员的大肠杆菌菌株进行比较分析.
- 转录组测序以确定差异表达的基因.
- 细胞活力测定,膜完整性测量和脂肪酸组成分析.
- 一种复合大肠杆菌菌株的料批发发酵,用于从酸中共同生产糖酸盐和PHB.
主要成果:
- 在乙酸压力下,PHB调动显著增加了大肠杆菌细胞活力 (52.8%对25.2%).
- PHB调动提高了 31.5% 的膜完整性,并改变了脂肪酸成分,增加了循环和不和脂肪酸的比例.
- 转录组分析显示了膜相关基因的改变表达,包括Bhsa.
- PHB调动改善了酸盐的耐受性和利用率,从而提高了酸盐 (23.93 g/L) 和PHB (7.21 g/L) 的联合生产.
结论:
- PHB调动是通过调节膜性质来提高大肠杆菌对乙酸压力的抵抗力的关键机制.
- PHB调动增强了酸作为碳来源用于微生物生长和产品形成的利用.
- 这项研究提出了一种新的策略,用于开发强大的大肠杆菌菌株,并有效地从乙中联合合成有价值的生物产品.
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