New mechanisms of sulfur sensing and trafficking in Staphylococcus aureus.

金黄色葡萄球菌硫传感和运输的新机制。

• 批准号: 8081409
• 负责人: DAVID P. GIEDROC
• 金额: $ 26.87万
• 依托单位: TRUSTEES OF INDIANA UNIVERSITY
• 依托单位国家: 美国
• 财政年份: 2011
• 资助国家: 美国
• 起止时间: 2011-04-01 至 2015-03-31
• 项目状态: 已结题
• 来源: https://reporter.nih.gov/project-details/8081409
• 关键词: 2-thiouridine; Affinity; Alkanesulfonates; Anabolism; Antibiotic Therapy; Area; Assimilations; Bacteria; Binding; Biochemical; Biogenesis; Biological Process; Cells; Chemicals; Community Hospitals; Community-Acquired Infections; Copper; Cysteine; Dioxygenases; Disease; Disulfides; Essential Amino Acids; Genes; Genetic Transcription; Homeostasis; Hospitals; Human; Hydrogen Sulfide; In Vitro; Incidence; Infectious Skin Diseases; Inorganic Sulfates; Intervention; Iron-Sulfur Proteins; Kinetics; Label; Low Prevalence; Mammals; Mass Spectrum Analysis; Mediating; Mental Depression; Metabolic; Metabolic Pathway; Metabolism; Methicillin Resistance; Methionine; Minor; Modeling; Modification; Molecular Genetics; Mycobacterium tuberculosis; NAD(P)H dehydrogenase (quinone) 1, human; Operon; Phenotype; Physiologic pulse; Proteins; Proteomics; Regulation; Regulon; Repression; Resistance; Resolution; Role; Sodium; Source; Staphylococcus aureus; Structure; Sulfhydryl Compounds; Sulfides; Sulfites; Sulfur; Sulfur Metabolism Pathway; System; Testing; Therapeutic; Thiamine; Thioctic Acid; Thiosulfate Sulfurtransferase; Toxic effect; Transcription Repressor/Corepressor; Transfer RNA; Unspecified or Sulfate Ion Sulfates; Vaccines; Work; antimicrobial; base; derepression; extracellular; in vivo; insight; mutant; novel; oxidation; paralogous gene; pathogen; persulfides; protein folding; research study; resistant strain; sulfurtransferase; trafficking

DESCRIPTION (provided by applicant): The Gram-positive opportunistic pathogen Staphylococcus aureus is the causative agent of minor skin infections to far more severe hospital and community-acquired diseases. New antibiotic therapies that target novel metabolic pathways are therefore urgently needed and sulfur metabolism represents one such validated antimicrobial and vaccine strategy. Staphylococcus aureus is characterized by a unique thiol metabolism and is strongly restricted in its ability to obtain inorganic sulfur to make cysteine, an essential amino acid. We have discovered a paralog of a copper-sensing transcriptional repressor CsoR (copper-sensitive operon repressor) in S. aureus strain Newman that we denote CstR, for CsoR-like sulfurtransferase repressor. CstR regulates the expression of a novel operon, cst, which encodes a putative sulfite/sulfonate effluxer (TauE) as well as two multidomain proteins that harbor canonical thiosulfate sulfurtransferase or rhodanese domains (CstA, CstB) whose biological functions are unknown. Our specific objectives are to (1) Elucidate the mechanistic basis of CstR-mediated repression and derepression of cst operon transcription; (2) Elucidate the structure and mechanism of the multidomain thiosulfate sulfurtransferase CstA, which we hypothesize harbors three sulfur relay modules that collectively mediate vectorial transfer of cysteine persulfides from donor to acceptor. NMR structural studies and a novel 34S-32SO32- pulse-32S-32SO32- chase experiment are proposed; (3) Identify cellular proteins that transiently carry 34S-persulfide groups originating with extracellular sodium 34S- 32SO3 thiosulfate using a "bottom-up" proteomics approach; and 4) Begin to elucidate the enzymatic activities of CstR-regulated gene products CstB, a putative rhodanese-containing sulfur dioxygenase and SQR, a putative sulfide:quinone oxidoreductase. This project will provide new insights into the mechanisms of sulfur metabolism and resistance to sulfur metabolite toxicity in an important human pathogen. These studies will significantly extend the emerging paradigm of a cysteine persulfide-based sulfur shuttling system in other bacteria to a new metabolic process as a potential novel antimicrobial intervention strategy. PUBLIC HEALTH RELEVANCE: Staphylococcus aureus is a recognized human pathogen and the causative agent of myriad severe hospital and community acquired infections. In this project, we propose studies to investigate the regulation and function of a novel sulfur metabolic operon in S. aureus that may serve as a new target for antimicrobial therapeutics.

描述（由申请方提供）：革兰氏阳性机会致病菌金黄色葡萄球菌是轻微皮肤感染到更严重的医院和社区获得性疾病的病原体。因此，迫切需要靶向新代谢途径的新抗生素疗法，硫代谢代表了一种这样的经验证的抗菌剂和疫苗策略。金黄色葡萄球菌的特征在于独特的硫醇代谢，并且在其获得无机硫以制造半胱氨酸（一种必需氨基酸）的能力方面受到强烈限制。我们在S.金黄色葡萄球菌菌株纽曼，我们将其表示为CstR，用于CsoR样硫转移酶阻遏物。CstR调节一种新的操纵子cst的表达，cst编码一种假定的亚硫酸盐/磺酸盐流出物（TauE）以及两种多结构域蛋白，其具有典型的硫代硫酸盐硫转移酶或罗丹酸结构域（CstA，CstB），其生物学功能未知。我们的具体目标是：（1）阐明CstR介导的cst操纵子转录的抑制和去抑制的机制基础;（2）阐明多结构域硫代硫酸盐硫转移酶CstA的结构和机制，我们假设它含有三个硫中继模块，共同介导半胱氨酸过硫化物从供体到受体的载体转移。（3）采用“自底向上”的蛋白质组学方法鉴定细胞内瞬时携带来源于细胞外34 S-32 SO_3硫代硫酸钠的34 S-过硫化物基团的蛋白质;和4）开始阐明CstR调节的基因产物CstB（一种假定的含硫氰酸根的硫双加氧酶）和SQR（一种假定的硫化物：醌氧化还原酶）的酶活性。该项目将提供新的见解硫代谢的机制和抗硫代谢物毒性在一个重要的人类病原体。这些研究将显着扩展新兴的范例，在其他细菌的半胱氨酸过硫化物为基础的硫穿梭系统的一个新的代谢过程作为一个潜在的新型抗菌干预策略。 公共卫生相关性：金黄色葡萄球菌是一种公认的人类病原体，是无数严重的医院和社区获得性感染的病原体。在这个项目中，我们提出了研究一个新的硫代谢操纵子在S。金黄色葡萄球菌，可以作为一个新的目标抗菌治疗。