Investigating the mechanism of phosphate aquisition by Pseudomonas aeruginosa

铜绿假单胞菌获取磷酸盐的机制研究

• 批准号: 401975-2011
• 负责人: Moraes, Trevor
• 金额: $ 2.99万
• 依托单位: University of Toronto
• 依托单位国家: 加拿大
• 项目类别: Discovery Grants Program - Individual
• 财政年份: 2015
• 资助国家: 加拿大
• 起止时间: 2015-01-01 至 2016-12-31
• 项目状态: 已结题
• 来源: https://www.nserc-crsng.gc.ca/ase-oro/Details-Detailles_eng.asp?id=573117
• 关键词: Investigating; mechanism; phosphate; aquisition; Pseudomonas

Phosphate is an essential nutrient that is found in lipids, nucleic acids, proteins and sugars and is also key to many biological reactions that require ATP and/or signaling pathways that exploit protein phosphorylation. Thus, bacteria utilize a global regulatory circuit, the Pho regulon, to manage intracellular bacterial phosphate homeostasis. The Pho regulon regulates the expression of key proteins involved in the acquisition of phosphate, including integral membrane proteins that play an important role in the transport of phosphate across lipid bilayers and into the cell. These membrane proteins also act as sensory proteins that interact with phosphate binding proteins to detect the levels of extracellular phosphate and in turn regulate their own expression through the Pho regulon. The Pho regulon pathway also controls many other gene networks including the expression and secretion of virulence factors in response to phosphate levels, thus this phosphate acquisition pathway in bacteria is extremely important. The integral membrane proteins (OprP and PstABC) that translocate phosphate interact with their aqueous soluble transport partners (PstS and PhoU) facilitating the transport of these anions and also initiate signaling events that are propagated to control gene expression. Research in the Moraes lab will examine the protein interactions between integral membrane protein transporters and their soluble transporter counterparts that lead to transport and signal transduction. We plan to dissect the components of this pathway and their interactions in molecular detail using tools such as X-ray crystallography to provide atomic resolution 3D- images of the proteins involved in phosphate translocation. Indeed, the high-resolution structure of the outer membrane protein OprP determined by Dr. Moraes provides insight into the first step of phosphate acquisition. Highly qualified personnel will be well trained in the areas of membrane protein structural biology, microbiology, biochemistry and molecular biology, preparing them for careers in basic scientific research and biotechnology.

磷酸盐是一种必需的营养物质，存在于脂质、核酸、蛋白质和糖中，也是许多生物反应的关键，这些反应需要ATP和/或利用蛋白质磷酸化的信号通路。因此，细菌利用一个全球调节电路Pho调节子来管理细胞内细菌磷酸盐的动态平衡。Pho调节子调节与磷酸盐获取有关的关键蛋白的表达，包括在磷酸盐跨脂双层运输和进入细胞的过程中发挥重要作用的整膜蛋白。这些膜蛋白还作为感觉蛋白与磷酸盐结合蛋白相互作用，检测胞外磷酸盐的水平，进而通过Pho调节子调节自己的表达。Pho调节子途径还控制着许多其他基因网络，包括毒力因子的表达和分泌，以响应磷酸盐水平，因此这一细菌获取磷酸盐的途径是极其重要的。 转运磷酸盐的整膜蛋白(OprP和PstABC)与其水溶转运伙伴(PstS和Phou)相互作用，促进这些阴离子的运输，并启动信号事件，这些信号事件被传播以控制基因的表达。Moraes实验室的研究将检查完整的膜蛋白转运体与其可溶性转运体之间的蛋白质相互作用，这些转运体导致运输和信号转导。我们计划使用X射线结晶学等工具，在分子细节上剖析这一途径的组成部分及其相互作用，以提供参与磷酸盐转运的蛋白质的原子分辨率3D图像。事实上，Moraes博士确定的外膜蛋白OprP的高分辨率结构为磷酸盐获取的第一步提供了洞察。高素质的人才将在膜蛋白结构生物学、微生物学、生物化学和分子生物学领域接受良好培训，为从事基础科学研究和生物技术工作做好准备。