Chemistry and Biology of Bacterial Sulfonucleotide Reductases

细菌磺核苷酸还原酶的化学和生物学

• 批准号: 8207992
• 负责人: Kate Suzanne Carroll
• 金额: $ 50.9万
• 依托单位: SCRIPPS FLORIDA
• 依托单位国家: 美国
• 财政年份: 2008
• 资助国家: 美国
• 起止时间: 2008-12-01 至 2013-11-30
• 项目状态: 已结题
• 来源: https://reporter.nih.gov/project-details/8207992
• 关键词: Adenosine; Adopted; Anabolism; Anti-Infective Agents; Antibiotics; Antioxidants; Bacteria; Binding; Biology; C-terminal; Catalysis; Catalytic Domain; Chemistry; Coenzymes; Cysteine; DNA Sequence Rearrangement; Data; Development; Docking; Electron Nuclear Double Resonance; Environment; Enzymes; Fluorescence Anisotropy; Fluorescence Spectroscopy; Goals; Health; Human; Infection; Inorganic Sulfates; Intercept; Iron; Lead; Libraries; Mediating; Metabolic Pathway; Metabolism; Methionine; Methods; Molecular; Molecular Conformation; Mossbauer Spectroscopy; Mycobacterium tuberculosis; Nature; Oxidoreductase; Pharmaceutical Preparations; Phase; Play; Process; Production; Protein Chemistry; Proteins; Pseudomonas aeruginosa; Public Health; Research; Resolution; Roentgen Rays; Role; Scientist; Screening procedure; Staging; Structure; Sulfides; Sulfites; Sulfur; Sulfur Metabolism Pathway; Thioredoxin; Time; Tuberculosis; Unspecified or Sulfate Ion Sulfates; Variant; Virulence; Work; adenylylsulfate reductase; antimicrobial; base; chemical reaction; chemotherapy; cofactor; combat; design; drug resistant bacteria; electronic structure; inhibitor/antagonist; insight; microbial; novel therapeutic intervention; pathogen; research study; small molecule; virtual

Sulfur metabolic pathways are essential for the virulence and survival of human pathogens. In microbial cysteine biosynthesis, sulfonucleotide reductases (SRs) catalyze the reduction of 5'-phosphosulfoadenosine (APS) or 3'-phospho-5'phosphosulfoadenosine (PAPS) to sulfite using reducing equivalents from a protein cofactor, thioredoxin (Trx). In later stages, sulfite is further reduced to sulfide, which is used for the production of essential sulfur-containing metabolites including cysteine, methionine, coenzymes, iron-sulfur clusters and antioxidants. SRs are excellent new targets for antibiotic development because of their critical role in bacterial survival and the lack of analogous enzymes in humans. This class of enzymes is particularly intriguing due to the nature of the chemical reaction they catalyze. In addition, our preliminary results suggest that a highly unusual iron-sulfur cluster in APS reductase may play an important catalytic role. However, many fundamental questions about their mechanism and structure remain unknown. Because the chemistry and biology of bacterial SRs is not well understood, scientists have not been able to explore the potential of these enzymes as anti-infective targets. To this end, the broad goal of this project is directed towards obtaining detailed mechanistic and structural information on bacterial SRs, and on identifying small molecule inhibitors of SRs. The proposed research has three Specific Aims: (1) To elucidate the function of the [4Fe-4S] cluster in APS reductase, (2) To investigate large-scale conformational dynamics in the SR catalytic cycle, and (3) To discover SR inhibitors using library screening and virtual docking approaches. This work may lead to the development of antibiotics that can be used to combat drug-resistant bacteria, which would have a major impact on human health. Furthermore, we anticipate that these experiments will lead to important new fundamental insights into the (bio)chemistry of protein-associated iron-sulfur clusters and bacterial sulfur metabolism.

硫代谢途径对于人类病原体的毒力和存活至关重要。在微生物中 半胱氨酸生物合成，磺核苷酸还原酶（SRS）催化5'-磷酸二腺苷的还原 （APS）或3'-磷-5''Phosphosulfoadenosine（PAPS）使用蛋白质还原等效物到亚硫酸盐 辅因子，硫氧还蛋白（TRX）。在以后的阶段，硫酸盐进一步还原为硫化物，用于生产 含硫的必需代谢产物，包括半胱氨酸，蛋氨酸，辅酶，铁硫簇和 抗氧化剂。 SR是抗生素开发的绝佳新靶标，因为它们在细菌中的关键作用 生存和人类缺乏类似酶。由于 它们催化的化学反应的性质。此外，我们的初步结果表明 APS还原酶中异常的铁硫簇可能起重要的催化作用。但是，许多基本 关于其机制和结构的问题仍然未知。因为化学和生物学 细菌SR不太了解，科学家无法探索这些酶的潜力 作为反感染靶标。为此，该项目的广泛目标是针对获得详细的 有关细菌SR的机械和结构信息，以及鉴定SRS的小分子抑制剂。 拟议的研究具有三个特定的目的：（1）阐明AP中[4FE-4S]群集的功能 还原酶，（2）研究SR催化循环中的大规模构象动力学，（3） 使用库筛选和虚拟对接方法发现SR抑制剂。这项工作可能导致 开发可用于对抗耐药细菌的抗生素，这将具有主要 对人类健康的影响。此外，我们预计这些实验将导致重要的新 对蛋白质相关的铁硫簇和细菌硫的（生物）化学的基本见解 代谢。