The Regulatory Networks that Allow Vibrio cholerae to Survive Between Infections and Epidemics

允许霍乱弧菌在感染和流行病之间生存的监管网络

• 批准号: 9811333
• 负责人: Jane May Liu
• 金额: $ 37.86万
• 依托单位: POMONA COLLEGE
• 依托单位国家: 美国
• 财政年份: 2010
• 资助国家: 美国
• 起止时间: 2010-06-15 至 2023-06-30
• 项目状态: 已结题
• 来源: https://reporter.nih.gov/project-details/9811333
• 关键词: Affect; Algae; Animal Model; Bacteria; Bacterial Infections; Bacterial Physiology; Binding; Binding Proteins; Carbohydrates; Carbon; Carrier Proteins; Cause of Death; Cholera; Communicable Diseases; Competence; Cues; Cyclic AMP; Data; Dehydration; Diarrhea; Disease; Disease Outbreaks; Enhancers; Environment; Epidemic; Escherichia coli; Fresh Water; Fructose; Funding; Future; Gene Expression; Genetic; Genetic Transcription; Goals; Habitats; Health; High-Throughput Nucleotide Sequencing; Hour; Income; Infection; Investigation; Left; Mannitol; Maps; Marines; Mass Spectrum Analysis; Mediating; Metabolism; Microbial Biofilms; Mission; Modeling; Molecular; Nutrient; Outcome; Output; Patients; Periodicity; Phosphoenolpyruvate; Phosphotransferases; Physiological; Physiology; Poverty; Process; Proteins; Proteomics; Public Health; RNA; Regulation; Regulator Genes; Regulatory Pathway; Research; Second Messenger Systems; Signal Pathway; Signal Transduction; Small RNA; Source; Stress; Sugar Alcohols; System; Testing; United States National Institutes of Health; Vibrio cholerae; Virulence; Water; aqueous; base; burden of illness; combat; environmental change; environmental flux; extracellular; genetic regulatory protein; human pathogen; innovation; multimodality; pathogenic bacteria; response; sugar; transcription factor; undergraduate student; waterborne illness

Vibrio cholerae, the causative agent of cholera, survives and persists in aquatic reservoirs that are subject to fluctuating nutrients and stresses. The bacteria have evolved adaptive responses that allow them to precisely react to these changing environmental inputs with fast and fine-tuned outputs. The molecular circuitry of these signaling networks, however, remains to be fully delineated. In order to better predict and control outbreaks in the future, there is a need for understanding how V. cholerae is able to enhance its aquatic persistence. Toward this end, the long-term goal of this research is to define regulatory mechanisms that V. cholerae uses to coordi- nate physiological responses to environmental cues, in particular, the presence of carbon sources like mannitol and fructose. Both sugars are transported into V. cholerae by the phosphotransferase system (PTS), which is a global regulator of gene expression that coordinates carbohydrate availability and bacterial physiology. Conse- quently, fluctuations in available PTS sugars affect the physiology of V. cholerae. The objective of this application is to elucidate the molecular mechanisms of these processes. The central hypothesis of this proposal is that the regulated expression of PTS components affects the expression of genes involved in biofilm formation by mod- ulating protein activity and second messenger concentrations. Biofilm formation enhances bacterial persistence and the hypothesis is based on results from the prior funding period studying regulation of the mannitol trans- porter (MtlA) of the PTS, a known biofilm enhancer. The rationale for this project is that determination of the mechanisms by which V. cholerae adapts its physiology to these environmentally important sugars will provide a framework from which new strategies to combat cholera can be developed. This project will pursue three aims: 1) Identify the mechanism by which expression of the gene encoding MtlA is repressed; 2) Determine MtlA- dependent and -independent mechanisms of PTS sugar-induced biofilm formation; 3) Map the global network of proteins and regulatory RNAs that modulate V. cholerae physiology upon nutrient shifts. Under the first aim, the genetic interaction between two regulators of mtlA will be tested, and additional factors that affect mtlA expres- sion will be identified. For the second aim, proteins that bind MtlA and impact MtlA-mediated biofilm formation will be determined. Additionally, proteins that impact cyclic diguanylate metabolism and mediate fructose-in- duced biofilm synthesis will be identified. Under the third aim, a combination of mass spectrometry and high- throughput sequencing will be used to identify the full suite of proteins and small RNAs associated with shifts of PTS sugars in the environment. The approach is innovative because it focuses on the survival of V. cholerae in fluctuating environments by defining mechanisms through which synthesis of PTS proteins are regulated and comparing the signaling pathways used by different PTS sugars to drive cellular responses related to persis- tence. The proposed research is significant because understanding how environmental fluxes impact biofilm formation will provide better warning signs of potential epidemics, ultimately decreasing cholera disease burden.

霍乱弧菌是霍乱的病原体，在受环境影响的水库中存活并持续存在。 营养物质和压力的波动。细菌已经进化出适应性反应，使它们能够精确地 通过快速且微调的输出对这些不断变化的环境输入做出反应。这些的分子电路 然而，信号网络仍有待充分界定。为了更好地预测和控制疫情 未来，我们需要了解霍乱弧菌如何增强其水生持久性。走向 为此，这项研究的长期目标是确定霍乱弧菌用来协调的调节机制。 对环境因素的自然生理反应，特别是甘露醇等碳源的存在 和果糖。这两种糖均通过磷酸转移酶系统 (PTS) 转运到霍乱弧菌中，该系统是一种 协调碳水化合物可用性和细菌生理学的基因表达的全局调节因子。康塞- 最后，可用 PTS 糖的波动会影响霍乱弧菌的生理机能。此应用程序的目的 的目的是阐明这些过程的分子机制。该提案的中心假设是 PTS成分的调节表达通过mod-影响参与生物膜形成的基因的表达 计算蛋白质活性和第二信使浓度。生物膜的形成增强细菌的持久性 该假设是基于先前资助期间研究甘露醇反式调节的结果 PTS 的波特尔 (MtlA)，一种已知的生物膜增强剂。该项目的基本原理是确定 霍乱弧菌使其生理学适应这些对环境重要的糖的机制将提供 一个可以制定新的防治霍乱战略的框架。该项目将追求三个目标： 1) 确定MtlA编码基因表达被抑制的机制； 2) 确定MtlA- PTS糖诱导生物膜形成的依赖和独立机制； 3) 绘制全球网络图 根据营养变化调节霍乱弧菌生理学的蛋白质和调节RNA。在第一个目标下， 将测试 mtlA 的两个调节因子之间的遗传相互作用，并且影响 mtlA 表达的其他因素 将被识别。对于第二个目标，结合 MtlA 并影响 MtlA 介导的生物膜形成的蛋白质 将被确定。此外，影响环状二鸟苷酸代谢并介导果糖的蛋白质 将鉴定诱导的生物膜合成。在第三个目标下，质谱和高通量分析相结合 通量测序将用于识别与转移相关的全套蛋白质和小RNA。 环境中的 PTS 糖。该方法具有创新性，因为它关注的是霍乱弧菌在 通过定义调节 PTS 蛋白合成的机制来调节环境波动 比较不同 PTS 糖用于驱动与持久相关的细胞反应的信号通路 紧张。拟议的研究意义重大，因为了解环境通量如何影响生物膜 形成将为潜在流行病提供更好的预警信号，最终减轻霍乱疾病负担。