The critical roles of (p)ppGpp in homeostasis and antibiotic tolerance in Gram positive bacteria

(p)ppGpp 在革兰氏阳性菌体内平衡和抗生素耐受性中的关键作用

• 批准号: 10623673
• 负责人: Jue D. Wang
• 金额: $ 45.66万
• 依托单位: UNIVERSITY OF WISCONSIN-MADISON
• 依托单位国家: 美国
• 财政年份: 2018
• 资助国家: 美国
• 起止时间: 2018-05-01 至 2028-02-29
• 项目状态: 未结题
• 来源: https://reporter.nih.gov/project-details/10623673
• 关键词: Antibiotic Resistance; Antibiotics; Bacillus; Bacillus anthracis; Bacillus subtilis; Bacteria; Biochemical; Biological; Cell Wall; Cell physiology; Cells; Cues; Development; Environment; Enzymes; Evolution; Genetic; Genetic Transcription; Goals; Gram-Positive Bacteria; Growth; Homeostasis; Knowledge; Laboratories; Life Style; Mediating; Metabolism; Microbial Biofilms; Nucleotides; Nutrient; Nutritional; Physiological; Process; Proteome; Proteomics; Purines; Regulation; Research; Resistance; Role; Signal Transduction; Starvation; Stress; Temperature; Transcription Repressor; Transcriptional Regulation; antibiotic tolerance; antimicrobial; assault; bacterial fitness; biological adaptation to stress; biophysical techniques; diadenosine tetraphosphate; experience; fitness; genetic manipulation; genome integrity; metabolomics; model organism; pathogen; pathogenic bacteria; response; transcriptomics; transmission process

Project Summary Bacteria frequently encounter stresses including nutrient starvation, temperature changes, and antibiotic assault, which could easily throw their intracellular environment into chaos. To survive and to adapt, bacteria developed diverse stress responses to regulate intracellular processes accordingly. While the transcriptional networks governing stress responses have been extensively characterized, there are major gaps in our knowledge beyond transcription regulation. The theme of my research is to elucidate stress signaling mechanisms that are transmitted by rapid changes in concentration of ‘alarmones’ – signaling nucleotides which are instrumental for alerting cells about stresses in a timely manner. My laboratory has extensive experience in characterizing the conserved alarmone (p)ppGpp. (p)ppGpp is induced by stresses and mediates profound, pleiotropic physiological changes in almost all bacteria to allow fitness, survival, and evolution. We identified multiple purine synthesis enzymes, a replication enzyme and a transcription repressor that are directly regulated by (p)ppGpp in Gram-positive Bacillus species. These regulations were further found to be conserved in many pathogens and are critical for homeostasis, starvation resistance, antibiotic persistence, and genome integrity. Currently, we are also investigating how (p)ppGpp regulates the switch between distinct bacterial lifestyles: planktonic growth and biofilm formation. Additionally, we detected other nucleotide alarmones including AppppA, pGpp, ppApp, and c-di- AMP, which are induced by different stresses including temperature and cell wall stress, to form a robust protective network. Our future research will answer the following fundamental questions: How are the different alarmones triggered by different stresses, and how do bacteria synthesize them? What are the direct interaction targets of different alarmones, and how do they promote bacterial fitness and influence bacterial development such as biofilm formation and sporulation? How do bacteria integrate multiple cues from different alarmones for rapid and appropriate adaptation to diverse environments? We combine metabolomics, transcriptomics, and proteomics with biochemical and cell biological approaches to answer these questions. We obtained a list of alarmone targets from systematic screens performed with the proteome of the pathogen Bacillus anthracis. We will study these processes in the related non-pathogenic bacterium Bacillus subtilis for which we have extensive experience. B. subtilis grows fast and is highly amenable to genetic manipulation. The nucleotide signaling mechanisms we characterize in Bacillus are applicable to other, less tractable, pathogenic bacteria, and can be used for developing antimicrobial strategies by targeting their stress responses.

项目概要 细菌经常遇到压力，包括营养缺乏、温度变化和 抗生素的攻击，很容易使它们的细胞内环境陷入混乱。 为了适应，细菌产生了不同的应激反应来调节细胞内过程 因此，控制应激反应的转录网络主要是。 就其特征而言，除了转录调控之外，我们的知识还存在重大差距。 我的研究是阐明通过快速变化传递的压力信号机制 “警报素”的浓度——信号核苷酸，有助于提醒细胞注意 我的实验室在表征保守性方面拥有丰富的经验。 警报酮 (p)ppGpp (p)ppGpp 由压力诱导并介导深刻的多效性。 我们确定了几乎所有细菌的生理变化，以适应、生存和进化。 多种嘌呤合成酶、复制酶和转录抑制子 革兰氏阳性芽孢杆菌中的 (p)ppGpp 直接调节这些调节。 发现在许多病原体中是保守的，对于体内平衡、抗饥饿、 目前，我们还在研究 (p)ppGpp 的作用。 调节不同细菌生活方式之间的转换：浮游生长和生物膜形成。 此外，我们还检测到其他核苷酸报警素，包括 AppppA、pGpp、ppApp 和 c-di- AMP，由包括温度和细胞壁应力在内的不同应力诱导，形成 我们未来的研究将回答以下基本问题：如何实现。 不同的压力会触发不同的警报素吗？细菌是如何合成它们的？ 不同警报素的直接相互作用靶标是什么，它们如何促进细菌生长 如何影响细菌的发育，例如生物膜的形成和孢子形成？ 细菌整合来自不同警报素的多种线索，以快速、适当地适应 我们将代谢组学、转录组学和蛋白质组学结合起来 我们获得了回答这些问题的生化和细胞生物学方法。 使用病原体芽孢杆菌的蛋白质组进行系统筛选的警报酮目标 我们将在相关的非致病性枯草芽孢杆菌中研究这些过程。 我们对此拥有丰富的经验。枯草芽孢杆菌生长速度快，并且非常适合遗传。 我们在芽孢杆菌中表征的核苷酸信号传导机制适用于操作。 其他不易处理的致病菌，可用于制定抗菌策略 通过针对他们的压力反应。