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。

基本信息

批准号：
8640194
负责人：
DAVID P. GIEDROC
金额：
$ 26.73万
依托单位：
TRUSTEES OF INDIANA UNIVERSITY
依托单位国家：
美国
项目类别：
财政年份：
2011
资助国家：
美国
起止时间：
2011-04-01 至 2016-03-31
项目状态：
已结题

来源：
https://reporter.nih.gov/project-details/8640194
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 public health relevance research study resistant strain sulfurtransferase trafficking

项目摘要

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.

描述（由申请人提供）：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，迫切需要针对新代谢途径的新抗生素疗法，硫代谢代表了一种经过验证的抗菌和疫苗策略。金黄色葡萄球菌具有独特的硫醇代谢特征，其获取无机硫以制造必需氨基酸半胱氨酸的能力受到强烈限制。我们在金黄色葡萄球菌 Newman 菌株中发现了铜敏感转录阻遏物 CsoR（铜敏感操纵子阻遏物）的旁系同源物，我们将其表示为 CstR，即 CsoR 样硫转移酶阻遏物。 CstR 调节新型操纵子 cst 的表达，cst 编码假定的亚硫酸盐/磺酸盐流出物 (TauE) 以及两种多结构域蛋白，这些蛋白含有典型的硫代硫酸盐硫转移酶或硫氰酸酶结构域 (CstA、CstB)，其生物学功能尚不清楚。我们的具体目标是（1）阐明CstR介导的cst操纵子转录抑制和去抑制的机制基础； (2)阐明多域硫代硫酸盐硫转移酶CstA的结构和机制，我们假设其包含三个硫中继模块，共同介导半胱氨酸过硫化物从供体到受体的矢量转移。提出了NMR结构研究和新型34S-32SO32-脉冲-32S-32SO32-追踪实验； (3) 使用“自下而上”的蛋白质组学方法鉴定瞬时携带源自细胞外 34S-32SO3 硫代硫酸钠的 34S-过硫化物基团的细胞蛋白； 4) 开始阐明 CstR 调节的基因产物 CstB（一种推定的含硫氰酸酶的硫双加氧酶）和 SQR（一种推定的硫化物：醌氧化还原酶）的酶活性。该项目将为重要人类病原体的硫代谢机制和对硫代谢物毒性的抵抗提供新的见解。这些研究将显着地将其他细菌中基于半胱氨酸过硫化物的硫穿梭系统的新兴范例扩展到新的代谢过程，作为潜在的新型抗菌干预策略。