The molecular mechanism linking respiratory NADH oxidation and virulence in Staphylococcus aureus

金黄色葡萄球菌呼吸NADH氧化与毒力的分子机制

• 批准号: 10611993
• 负责人: ROBERT B GENNIS
• 金额: $ 51.92万
• 依托单位: UNIVERSITY OF ILLINOIS AT URBANA-CHAMPAIGN
• 依托单位国家: 美国
• 财政年份: 2020
• 资助国家: 美国
• 起止时间: 2020-05-23 至 2025-04-30
• 项目状态: 未结题
• 来源: https://reporter.nih.gov/project-details/10611993
• 关键词: Aerobic; Affect; Animals; Bacteria; Biochemical; Biochemistry; Bioenergetics; Cell physiology; Cells; Cytochrome c Reductase; Dangerousness; Data; Development; Disease; Elements; Environment; Enzymes; Evolution; Gene Expression Profiling; Generations; Genetic; Genus staphylococcus; Goals; Growth; Human body; In Vitro; Infection; Kinetics; Knock-out; Knowledge; Link; Membrane; Membrane Proteins; Metabolic; Metabolic Pathway; Metabolism; Methods; Microbial Biofilms; Molecular; Monitor; Morbidity - disease rate; Multi-Drug Resistance; NADH; Nebraska; Nitrates; Nutrient; Organ; Organism; Oxidation-Reduction; Oxygen; Pathogenesis; Pattern; Process; Production; Proteins; Proteomics; Qualifying; Regulation; Respiration; Respiratory Chain; Role; Signal Induction; Signal Transduction; Signaling Molecule; Site; Staphylococcus aureus; Staphylococcus aureus infection; System; Techniques; Technology; Testing; United States; Universities; Variant; Virulence; Virulence Factors; Vitamin K 2; alpha Toxin; cost; differential expression; flexibility; interdisciplinary approach; metabolomics; microfluidic technology; mortality; new therapeutic target; oxidation; pathogen; pathogenic bacteria; promoter; protein purification; respiratory; respiratory enzyme; sensor histidine kinase; therapeutically effective

ABSTRACT Staphylococcus aureus infections are a major cause of morbidity and mortality in the United States and across the globe. This is largely due to the evolution of multidrug-resistance and the ability of the bacterium to adapt its metabolism and bioenergetics to infect nearly every site of the human body. Thus, there is a significant need for the development of effective therapeutics against this organism. There are several critical gaps in our knowledge of how metabolic pathways used by S. aureus in different environments influence this pathogen virulence in vitro and inside the host. Therefore, our long-term goal is to elucidate how S. aureus receives signals from the environment in the host (e.g. oxygen concentration, nutrients), senses its own redox poise and energy status, and triggers metabolic changes, including the production of virulence factors. Our previous studies identified two respiratory enzymes in S. aureus called type 2 NADH dehydrogenases (NDH-2s: NdhC and NdhF) and revealed their importance for animal infection and organ colonization, and the production of virulence factors and biofilm formation in vitro. These results lead to our central hypothesis that the NADH-dependent respiratory chain is primarily responsible for controlling the NADH/NAD+ and MQH2/MQ (menaquinol/menaquinone) pools that are used by the cell to monitor its redox status and which we propose are major elements regulating virulence via specific global regulators. Guided by strong preliminary data, we propose to pursue three Specific Aims: (1) Determine the metabolic pathways utilized both in the presence and absence of each of the two NADH dehydrogenase enzymes, and the molecular mechanisms by which these enzymes modulate the production of α-toxin; (2) Determine why the presence of both NADH dehydrogenase enzymes is important for biofilm formation; (3) Determine if menaquinol is the signaling molecule that directly induces SrrB and SaeS autokinase activity in the SaeRS and SrrAB two-component systems, which are both critical for the regulation of virulence and biofilm formation. To accomplish these Aims, we have assembled a powerful team to employ a multidisciplinary approach that combines metabolomics, proteomics, genetics, microfluidics technology and biochemistry. Collectively, our proposed studies will have a broad impact on the field by uncovering the role of the respiratory chain in connecting environment signals with the intracellular redox poise that regulates S. aureus virulence. In the long term, these studies may reveal novel therapeutic targets to treat S. aureus-related diseases.

抽象的 金黄色葡萄球菌感染是美国及其跨越的发病率和死亡率的主要原因 地球。这在很大程度上是由于多药抗性的演变以及细菌适应的能力 它的代谢和生物能学几乎感染了人体的每个部位。那是一个重要的 需要开发针对这种生物的有效疗法。我们有几个关键差距 了解金黄色葡萄球菌在不同环境中使用的代谢途径如何影响这种病原体 体外和宿主内部的毒力。因此，我们的长期目标是阐明金黄色葡萄球菌如何获得 来自宿主环境的信号（例如氧气浓度，营养素），感觉自己的氧化还原和 能量状态和触发代谢变化，包括病毒因素的产生。 我们以前的研究确定了金黄色葡萄球菌中的两种呼吸酶，称为2型NADH脱氢酶 （NDH-2S：NDHC和NDHF），并揭示了它们对动物感染和器官定殖的重要性，以及 在体外生产病毒因子和生物膜形成。这些结果导致我们的中心假设，即 NADH依赖性呼吸链主要负责控制NADH/NAD+和MQH2/MQ （Menaquinol/Menaquinone）细胞用来监测其氧化还原状态的池，我们建议 是通过特定的全球调节剂控制病毒的主要元素。在强大的初步数据的指导下，我们 购买三个特定目标的提议：（1）确定在存在下使用的代谢途径 以及两个NADH脱氢酶中的每一种，以及分子机制 这些酶调节α-毒素的产生； （2）确定为什么两个NADH的存在 脱氢酶对生物膜的形成很重要。 （3）确定梅纳喹醇是否是信号传导 直接诱导SRRB和SAES自动激酶活性的分子和SRRAB两组分子 系统，这对于调节病毒和生物膜形成至关重要。为了实现这些目标， 我们已经组建了一个强大的团队，采用一种将代谢组学结合的多学科方法， 蛋白质组学，遗传学，微流体技术和生物化学。 总的来说，我们提出的研究将通过发现该领域的作用，从而对该领域产生广泛的影响 连接环境信号的呼吸链与调节金黄色葡萄球菌的细胞内氧化还原毒物 病毒。从长远来看，这些研究可能揭示了治疗金黄色葡萄球菌相关的新型治疗靶标 疾病。