酵母中葡萄糖阻遏作用机制研究进展

Mechanism of glucose repression in yeast

摘要:

大多数微生物通过一种复杂的机制来感知和传递环境中的葡萄糖变化并对其做出适当的反应。酵母细胞中,葡萄糖主要通过Snf1/Mig1信号通路来阻遏三羧酸循环、糖异生、乙醛酸循环和替代碳源代谢等相关基因的转录表达。木糖、半乳糖、蔗糖、乙醇和有机酸等替代碳源只有当环境中的葡萄糖消耗殆尽后才能重启代谢编程,进行替代碳源的利用。而葡萄糖去抑制对于提高现代微生物工业生产效率、解决环境与能源问题具有重要意义。本文综述了Snf1/Mig1信号通路阻遏机制以及相关转录因子的活性位点,具体介绍了多种替代碳源的应用以及其受葡萄糖阻遏的具体机制,总结提出了根据不同背景缓解或解除碳代谢阻遏的策略,以期为酵母菌现代化生产应用范围的扩大和效率的提高提供新思路。

Abstract:

Most microorganisms respond to glucose via complicated sensing and signaling mechanisms. In yeast cells, glucose represses the expression of genes involved in the tricarboxylic acid cycle, gluconeogenesis, glyoxylate cycle, and alternative carbon source metabolism mainly through the Snfl/Mig1 signaling pathway. Alternative carbon sources such as xylose, galactose, sucrose, ethanol, and organic acids reset the sugar metabolism only upon the full consumption of glucose in the environment. Derepression of glucose is of great significance for improving the production efficiency of modern microbial industry and addressing environmental and energy issues. This paper introduces the repression mechanism of Snf1/Mig1 signaling pathway and the active sites of related transcription factors. Specifically, we introduce the application of alternative carbon sources and the corresponding mechanisms of glucose repression. Finally, we summarize the solutions to relieving glucose repression on the basis of different backgrounds. This review aims to provide new ideas for expanding the applications and improving the efficiency of modern yeast production.