Interplay of Transition Metal Homeostasis and Reactive Sulfur Species in Bacterial Pathogens

细菌病原体中过渡金属稳态与活性硫的相互作用

• 批准号: 9071683
• 负责人: DAVID P. GIEDROC
• 金额: $ 57.92万
• 依托单位: TRUSTEES OF INDIANA UNIVERSITY
• 依托单位国家: 美国
• 财政年份: 2016
• 资助国家: 美国
• 起止时间: 2016-06-01 至 2021-05-31
• 项目状态: 已结题
• 来源: https://reporter.nih.gov/project-details/9071683
• 关键词: Acinetobacter baumannii; Anti-Bacterial Agents; Antibiotic Resistance; Area; Bacteria; Biological; Cells; Communicable Diseases; Communities; Copper; Cysteine; Development; Future; Goals; Health; Homeostasis; Human; Hydrogen Sulfide; Immunity; Investigation; Life; Link; Manganese; Mass Spectrum Analysis; Mediating; Metals; Microbial Biofilms; Microbial Physiology; Molecular; Morbidity - disease rate; Multi-Drug Resistance; Mycobacterium tuberculosis; Nitric Oxide; Nitrogen Oxides; Nosocomial Infections; Nutrient; Nutritional; Organism; Oxidative Stress; Pneumonia; Probability; Process; Proteome; Relaxation; Resistance; Site-Directed Mutagenesis; Staphylococcus aureus; Streptococcus pneumoniae; Stress; Sulfhydryl Compounds; Sulfides; Sulfur; Sulfur Metabolism Pathway; System; Toxic effect; Transcription Repressor/Corepressor; Transcriptional Regulation; Transition Elements; Vancomycin resistant enterococcus; Virulence; World Health Organization; Zinc; antimicrobial; base; biophysical chemistry; insight; interdisciplinary approach; interest; methicillin resistant Staphylococcus aureus; nitroxyl; novel; pathogen; protein transport; public health relevance; research study; respiratory; response; transcriptomics

 DESCRIPTION (provided by applicant): Infectious disease is a global threat to human health. The World Health Organization notes a pressing need to develop novel antimicrobial strategies that limit the impact of these life-threatening pathogens. These pathogens include the major causative agents of nosocomial infections, e.g., Staphylococcus aureus, and a major respiratory pathogen responsible for community-acquired pneumonia and morbidity world-wide, Streptococcus pneumoniae. Each is becoming increasingly multidrug-resistant severely complicating treatment options. In this proposal, we seek to integrate our fundamental studies of bacterial transition metal (manganese, copper and zinc) homeostasis, sulfur metabolism and sulfide homeostasis to accelerate the pace of discovery of novel antibacterial strategies. We have long-standing interests in the transcriptional repressors and more recently, metal trafficking proteins, that allow a bacterium to adapt to host-mediated "remodeling" of transition metal availability. We've discovered and structurally characterized new players in this process in M. tuberculosis, S. aureus and S. pneumoniae and have framed our quantitative investigations of these systems as "allosteric inorganic switches" that orchestrate metal homeostasis and resistance to toxicity in cells. These studies led directly to the discovery and ongoing elucidatio of what we anticipate represents a novel, highly specific regulatory response to reactive sulfur species (RSS) and potentially, reactive nitrogen oxide species (nitroxyl; HNO) in S. aureus. We hypothesize that this response impacts the ability of S. aureus and other pathogens to regulate colonization and nitric oxide (NO)-mediated dispersal of biofilms (biofilm dynamics) and resistance to antibiotic-induced oxidative stress. Future studies will be carried out in three general areas: 1) biological characterization and structural/dynamics studies, using state-of-the-art methyl-specific NMR relaxation experiments, of new allosteric systems involved in metalloregulation of transcription and regulation of RSS and RNOS; 2) obtaining new molecular-level insights into copper resistance and manganese homeostasis in S. pneumoniae, and mechanisms of adaptation to extreme zinc limitation induced by host-mediated "nutritional immunity" in Acinetobacter baumannii, and 3) holistically probe the cellular response to sulfide and RNOS stress using transcriptomic, mass spectrometry-based profiling of proteome cysteine thiol oxidative modifications, and targeted metabolite profiling approaches, with the goal to identity new players and mechanisms in this process. Our multidisciplinary approach, which seamlessly spans biophysical chemistry to microbial physiology, enhances the probability of transforming our understanding of fundamental features of transition metal homeostasis linked to virulence and a completely unexplored cellular response to RSS/RNOS in important human pathogens.

 描述（由适用提供）：传染病是对人类健康的全球威胁。世界卫生组织指出，迫切需要开发新颖的抗菌策略，以限制这些威胁生命的病原体的影响。这些病原体包括医院感染的主要结构药物，例如金黄色葡萄球菌，以及负责社区获得性肺炎和全球发病率的主要呼吸道病原体，肺炎链球菌。每个人都变得越来越多地抗药性地严重复杂的治疗选择。在该提案中，我们试图整合细菌过渡金属（锰，铜和锌）稳态，硫代谢和硫化物稳态的基本研究，以加快发现新型抗细菌策略的速度。我们对转录表示具有长期的兴趣，最近是金属运输蛋白，使细菌可以适应过渡金属可用性的宿主介导的“重塑”。我们在结核分枝杆菌，金黄色葡萄球菌和肺炎链球菌中发现并在结构上描述了新参与者，并将对这些系统的定量研究构建为“变构无机开关”，它们将金属稳态和对细胞中毒性的抗性卵形。这些研究直接导致了我们预期的发现和持续的阐明，代表了对反应性硫种（RSS）的新型，高度特异性的调节反应，以及在金黄色葡萄球菌中的反应性氮氧化物物种（硝基氧基； HNO）。我们假设这种反应会影响金黄色葡萄球菌和其他病原体调节定植和一氧化氮（NO）介导的生物膜分散（生物膜动力学）以及对抗生素诱导的氧化应激的抗性。未来的研究将在三个一般领域进行：1）使用最先进的甲基特异性NMR弛豫实验的生物学表征和结构/动力学研究，该实验是针对RSS和RNOS的转录和调节的新的变构系统； 2）在肺炎链球菌中获取对铜耐药性和锰稳态的新分子水平见解，以及适应对宿主介导的“营养免疫力”在骨无杆菌中诱导的极端锌限制的机制，用于baumannii，以及3）基于整体探针的质量范围，3）质量探测质量范围的范围范围。蛋白质组半胱氨酸硫醇氧化物的修饰和靶向代谢物分析方法，其目标是在此过程中确定新参与者和机制。我们的多学科方法无缝地跨越生物物理化学技术到微生物生理学，提高了我们对与病毒相关的过渡金属稳态的理解的理解，这些稳态与病毒相关，以及对重要人病原体中RSS/RNO的完全意外的细胞反应。