Using EPR to characterise the role of specific mechanosensitive channels in yeast cells involved in stress response

全球经济对化石原材料的依赖是不可持续的。使用微生物作为细胞工厂，从可再生生物质中生产有价值的化合物的生物技术过程是一个有吸引力的替代方案，使用这种策略可以工业化生产许多高价值的化学品。然而，由于产品产量低且比化学合成昂贵，许多微生物过程没有在工业水平上实施。众所周知，微生物在生物加工过程中表现出应激反应，而细胞工厂的低产品产量是因为生产条件最终对细胞有害，通常是在细胞膜水平。明显以膜为中心的压力的例子是溶剂，例如梭状芽胞杆菌产生丁醇和酵母产生乙醇，以及弱酸，例如由细菌产生的乳酸。本项目旨在了解工业微生物的细胞膜，以提高生物处理过程中的应激耐受性。机械敏感通道(MSCs)种类繁多，广泛存在于活细胞中，在机械传感传递施加在细胞膜上的机械力方面发挥着重要作用。它们将这种刺激转化为各种电和/或化学的细胞内信号。本项目旨在利用分子生物学技术和电子顺磁共振(EPR)技术，鉴定参与酵母应激反应(如酒精暴露、渗透压休克)的关键MSCs，并了解它们的作用。这些洞察力将进一步加深我们的理解，并提供一个机会，以发现新的方法来设计更耐受的微生物，获得更高的产品产量。

The global economy has an unsustainable dependence on fossil raw materials. Biotechnological processes using microorganisms as cell factories to produce valuable compounds from renewable biomass are an attractive alternative, and many high-value chemicals can be produced at an industrial scale using this strategy. However, many microbial processes are not implemented at industrial level due to poor product yield and being more expensive than chemical synthesis.It is well-established that microbes show stress responses during bioprocessing and poor product yields from cell factories are because production conditions are ultimately toxic to the cells, often at the level of the cell membrane. Examples of stresses that are demonstrably membrane-centric are solvents, e.g. butanol production by Clostridia and ethanol production by yeast, and weak acids such a lactic acid produced by bacteria. This project will seek to understand the cell membrane of industrial microbes to increase tolerance to stresses during bioprocessing.Mechanosensitive channels (MSCs) are diverse, ubiquitous to living cells and play an important role in mechanosensory transduction of mechanical force exerted on the membrane. They convert this stimulus into a variety of electrical and/or chemical intracellular signals. This project aims to identify key MSCs involved in yeast stress responses (e.g ethanol exposure, osmotic shock) and to understand their roles using molecular biology techniques and electron paramagnetic resonance (EPR). These insights would further our understanding and provide an opportunity to discover novel ways to engineer more 'tolerant' microbes with greater product yields.