Key Laboratory of Carbohydrate Chemistry and Biotechnology, Ministry of Education, Jiangnan University, Wuxi, 214122, China.
School of Chemical and Biomolecular Engineering, Georgia Institute of Technology, Atlanta, GA, 30332, USA.
Appl Microbiol Biotechnol. 2017 May;101(10):3991-4008. doi: 10.1007/s00253-017-8264-y. Epub 2017 Apr 13.
Environmental stresses are usually active during the process of microbial fermentation and have significant influence on microbial physiology. Microorganisms have developed a series of strategies to resist environmental stresses. For instance, they maintain the integrity and fluidity of cell membranes by modulating their structure and composition, and the permeability and activities of transporters are adjusted to control nutrient transport and ion exchange. Certain transcription factors are activated to enhance gene expression, and specific signal transduction pathways are induced to adapt to environmental changes. Besides, microbial cells also have well-established repair mechanisms that protect their macromolecules against damages inflicted by environmental stresses. Oxidative, hyperosmotic, thermal, acid, and organic solvent stresses are significant in microbial fermentation. In this review, we summarize the modus operandi by which these stresses act on cellular components, as well as the corresponding resistance mechanisms developed by microorganisms. Then, we discuss the applications of these stress resistance mechanisms on the production of industrially important chemicals. Finally, we prospect the application of systems biology and synthetic biology in the identification of resistant mechanisms and improvement of metabolic robustness of microorganisms in environmental stresses.
环境胁迫通常在微生物发酵过程中活跃，并对微生物生理学产生重大影响。微生物已经发展出一系列策略来抵抗环境胁迫。例如，它们通过调节细胞膜的结构和组成来保持细胞膜的完整性和流动性，并且调整转运体的通透性和活性以控制营养物质的运输和离子交换。某些转录因子被激活以增强基因表达，并且诱导特定的信号转导途径以适应环境变化。此外，微生物细胞还具有完善的修复机制，可以保护其大分子免受环境胁迫造成的损害。氧化、高渗、热、酸和有机溶剂胁迫在微生物发酵中很重要。在这篇综述中，我们总结了这些应激作用于细胞成分的方式，以及微生物发展的相应抵抗机制。然后，我们讨论了这些应激抵抗机制在工业上重要化学品生产中的应用。最后，我们展望了系统生物学和合成生物学在鉴定抵抗机制和提高微生物在环境应激下的代谢稳健性方面的应用。
