Intercellular Signalling in Vibrio harveyi

哈维氏弧菌的细胞间信号转导

• 批准号: 0094447
• 负责人: Bonnie Bassler
• 金额: $ 39万
• 依托单位: Princeton University
• 依托单位国家: 美国
• 项目类别: Continuing Grant
• 财政年份: 2001
• 资助国家: 美国
• 起止时间: 2001-03-01 至 2004-02-29
• 项目状态: 已结题
• 来源: https://www.nsf.gov/awardsearch/showAward?AWD_ID=0094447&HistoricalAwards=false
• 关键词: Intercellular; Signalling; Vibrio; harveyi

The long term goal of this research is to explore the molecular mechanisms that bacteria use for inter-cellular communication. This project focuses on a study of quorum sensing in the model bioluminescent marine bacterium Vibrio harveyi. It has been demonstrated that V. harveyi has two quorum sensing circuits (Signaling System 1 and Signaling System 2) that converge to regulate light production (Lux). Each system is made up of a two-component sensor-auto-inducer pair: LuxN/AI-1 for System 1 and LuxPQ/AI-2 for System 2. Both sensors transduce information to a shared phosphorelay protein, LuxU, which in turn conveys the signal to the response regulator protein LuxO. Phospho-LuxO is indirectly responsible for repression of luciferase production at low cell density, because it activates the expression of a negative regulator of Lux. A transcriptional activator protein, LuxR, is also required for expression of the luciferase structural operon (luxCDABEGH). Results suggest that V. harveyi uses Signaling System 1 and AI-1 for intra-species communication and Signaling System 2 and AI-2 for inter-species communication. Many bacteria including a number of clinically important pathogens produce AI-2. The goal of this project is to identify and characterize components of the V. harveyi multi-channel quorum sensing signalling pathway, to determine the functions and interactions of the different signalling proteins, and to determine the mechanism of signal integration by the two systems. The analysis of this regulatory network will lead to a molecular understanding of how bacteria integrate, process and transduce sensory information to control gene expression in response to inter-cellular communication. Analysis of this circuit should be valuable for understanding how bacteria perceive and react to their environment, how they communicate with one another and with other species of bacteria, and how they architect elaborate community structures. Since the regulatory process is complex and involves intra-cellular, inter-cellular, intra-species and inter-species signal transmission, interesting new mechanisms could be revealed.

这项研究的长期目标是探索细菌用于细胞间通讯的分子机制。 本计画主要研究以生物发光海洋细菌哈维氏弧菌为模式的群体感应。 已经证明，哈维氏弧菌具有两个群体感应电路（信号传导系统1和信号传导系统2），其会聚以调节光产生（Lux）。每个系统由双组分传感器-自动感应器对组成：系统1的LuxN/AI-1和系统2的LuxPQ/AI-2。 两种传感器都将信息传递给共享的磷酸化蛋白LuxU，后者又将信号传递给反应调节蛋白LuxO。 Phospho-LuxO间接地负责在低细胞密度下抑制荧光素酶的产生，因为它激活Lux的负调节因子的表达。 转录激活蛋白LuxR也是荧光素酶结构操纵子（luxCDABEGH）表达所需的。 结果表明，哈维氏弧菌利用信号系统1和AI-1进行种内通讯，利用信号系统2和AI-2进行种间通讯。 许多细菌，包括许多临床上重要的病原体，产生AI-2。 该项目的目标是识别和表征哈维氏弧菌多通道群体感应信号通路的组分，以确定不同信号蛋白的功能和相互作用，并确定两个系统的信号整合机制。对这一调控网络的分析将有助于从分子水平上了解细菌如何整合、处理和调控感官信息，以控制基因表达，从而响应细胞间的通讯。对这个回路的分析对于理解细菌如何感知和反应它们的环境，它们如何相互交流以及与其他细菌物种的交流，以及它们如何构建复杂的社区结构应该是有价值的。由于调控过程是复杂的，涉及细胞内，细胞间，种内和种间的信号传递，有趣的新机制可能会被揭示。