Mechanoregulation of EHEC virulence

项目摘要 环境感知是生物体适应其生理以响应环境变化的能力的基础。 其niche。在过去的几年里，人们发现细菌不仅能感知和响应化学刺激， 但是能够感知和处理作为环境线索的物理力。在细菌的情况下， 病原体，我们和其他人已经表明，机械刺激可以作为宿主定植的标志， 导致毒力基因激活。尽管有这样的认识，我们对途径的机械理解， 涉及机械感测、转换和处理物理力的系统目前是有限的， 我们对宿主环境中机械调节作用的了解。我们的目标是 了解肠出血性E.大肠杆菌是一种重要的人类病原体，对物理力有反应。在 人类宿主，摄入肠出血性大肠杆菌可导致小肠结肠炎和严重并发症，如溶血性尿毒症 综合征感染的这些特征是由毒力因子的协同作用引起的，包括 定植因子和志贺样毒素。在这里，我们将（a）描述毒力基因诱导如何响应 （B）确定膜与细胞之间信号转导的生化基础， 转录调节因子，和（c）定义在环境之间的转换过程中机械传感的作用 和宿主相关的生活方式这项工作将揭示肠出血性大肠杆菌如何感知和处理物理力量， 整合这些线索来协调它们的感染周期。这些知识可能会突出新的目标， 开发抗感染策略，通过使病原体对宿主“麻木”来使病原体失效。

PROJECT SUMMARY Environmental sensing is at the basis of an organism’s ability to adapt its physiology to respond to changes in its niche. Over the past years, it has emerged that bacteria not only perceive and respond to chemical stimuli, but are capable of sensing and processing physical forces as an environmental cue. In the case of bacterial pathogens, we and others have shown that mechanical stimuli can act as a hallmark of host colonization and lead to activation of virulence genes. Despite this realisation, our mechanistic understanding of pathways and systems involved in mechanosensing, transduction and processing of physical forces is currently limited, as is our knowledge regarding the role of mechanoregulation within the host environment. The objective here is to understand how enterohemorrhagic E. coli, an important human pathogen, responds to physical force. In the human host, ingestion of EHEC can lead to enterocolitis and severe complications such as haemolytic uremic syndrome. These hallmarks of infection are caused by the concerted action of virulence factors, including colonization factors and Shiga-like toxins. Here, we will (a) characterize how virulence gene induction responds to physical forces, (b) determine the biochemical basis of signal transduction between membrane and transcriptional regulator, and (c) define the role of mechanosensing during the transitions between environmental and host-associated lifestyles. This work will reveal how EHEC perceive and process physical forces, and integrate these cues to coordinate their infection cycle. Such knowledge may highlight new targets for the development of anti-infective strategies that disable the pathogen by rendering it ‘numb’ to the host.