Toxic Metal Complexation by de Novo Designed Peptides

de Novo 设计的肽与有毒金属络合

• 批准号: 8230719
• 负责人: VINCENT L PECORARO
• 金额: $ 26.74万
• 依托单位: UNIVERSITY OF MICHIGAN AT ANN ARBOR
• 依托单位国家: 美国
• 财政年份: 2003
• 资助国家: 美国
• 起止时间: 2003-06-09 至 2014-02-28
• 项目状态: 已结题
• 来源: https://reporter.nih.gov/project-details/8230719
• 关键词: Acute; Address; Adverse effects; Affinity; Amino Acids; Arsenic; Bacteria; Binding; Binding Sites; Biochemistry; Biological; Biological Process; Blood; Brain Injuries; Cadmium; Cessation of life; Chemistry; Child; Chronic; Communities; Complex; Confusion; Copper; Crystallography; Cysteine; DNA; DNA-Protein Interaction; Drug Metabolic Detoxication; Elements; Encapsulated; Environment; Evaluation; Excision; Exposure to; Foundations; Generations; Genetic Transcription; Goals; Headache; Health; Heavy Metals; Histidine; Human; Individual; Ions; Kinetics; Knowledge; Lead; Ligands; Location; Long-Term Effects; Mercury; Metal Binding Site; Metalloproteins; Metals; Modeling; Molecular; Molecular Chaperones; NMR Spectroscopy; Nausea and Vomiting; Organism; Peptides; Process; Property; Protein Binding; Proteins; Reaction; Reactive Oxygen Species; Regimen; Reporting; Repressor Proteins; Research; Resolution; Series; Site; Solutions; Specificity; Structure; Sulfhydryl Compounds; Symptoms; System; Therapeutic; Thermodynamics; Time; Toxic effect; Toxin; Transition Elements; Water; Work; Zinc; abstracting; aqueous; base; biological systems; design; exposed human population; fungus; insight; interest; metal poisoning; metalloregulatory protein; molecular recognition; novel; peptide structure; polypeptide; preference; prevent; resistance mechanism; respiratory; small molecule; success; toxic metal

DESCRIPTION (provided by applicant): Abstract Heavy metal poisoning by elements such as mercury, lead, cadmium, and arsenic is a significant human health problem. Understanding the interaction of heavy metals with proteins is essential for defining the mechanism of toxicity, developing ways to minimize human exposure and to provide therapeutic regimens for the removal of toxic ions. Our goals are (1) to develop peptide systems that provide a foundation for understanding metal binding by metalloregulatory proteins and metallochaperones, (2) to understand the thermodynamics and kinetics of heavy metals in helical assemblies and (3) to prepare new designed peptides utilizing different ligands (e.g., histidine or D-amino acids) or asymmetric binding sites in single polypeptides that fold into 1-helical bundles. To achieve these goals we will use a de novo peptide system based on the three-stranded coiled coil peptide aggregate motif that encapsulates with high affinity single heavy metal ions and provides spectroscopic models of mercury, cadmium, and arsenic binding sites in biological systems. We will generate high resolution structures of this peptide system in the presence and absence of these heavy metals, elucidate the kinetic and thermodynamic mechanisms of heavy metal encapsulation, and expand the array of characterized systems to include single chain peptides that encapsulate heavy metals, coiled coils that provide different coordination environments than the original design and those that encapsulate more than one heavy metal ion. These studies will expand the foundation of knowledge that has been laid by the scientific community investigating metallopeptide design, metalloregulatory proteins and heavy metal detoxification. These objectives will develop insight into the interplay between metal coordination and apopeptide structure in defining the overall metallopeptide fold, an important aspect of metallopeptide design. PUBLIC HEALTH RELEVANCE: Relevance to Human Health Heavy metals such as PbII, HgII, AsII and CdII cause severe health concerns due both to their acute toxicity and the long term effects of chronic exposure (e.g., the EPA estimated in 2002 that over 300,000 children in the USA had blood levels exceeding 10 ?g/dL). Our studies address these concerns in numerous ways: including making mimics of heavy metal binding sites in proteins in order to understand how heavy metals bind to proteins, defining the rates at which reactions occur and establishing the thermodynamic preferences of these metals to different sites. We are also relating this work to studies on proteins used to recognize or detoxify heavy metals in bacteria, fungi and humans (e.g., assessing how HgII interacts with the human copper chaperone HAH1).

描述(由申请人提供)： 摘要汞、铅、镉、砷等元素引起的重金属中毒是严重的人类健康问题。了解重金属与蛋白质的相互作用对于确定毒性机制、开发将人体暴露降至最低的方法以及为去除有毒离子提供治疗方案至关重要。我们的目标是(1)开发多肽系统，为了解金属调节蛋白和金属配位体与金属的结合提供基础；(2)了解重金属在螺旋组件中的热力学和动力学；(3)利用不同的配体(例如组氨酸或D-氨基酸)或单肽中的不对称结合位置制备新设计的多肽，这些多肽折叠成1-螺旋束。为了实现这些目标，我们将使用一个基于三链卷曲多肽聚集基序的从头肽系统，该基序包裹着高亲和力的单一重金属离子，并提供生物系统中汞、镉和砷结合位置的光谱模型。我们将在这些重金属的存在和不存在的情况下生成这个多肽系统的高分辨结构，阐明重金属包裹的动力学和热力学机制，并扩大表征系统的阵列，包括包裹重金属的单链多肽，提供与原始设计不同的配位环境的盘绕线圈，以及那些包裹多个重金属离子的系统。这些研究将扩大科学界研究金属肽设计、金属调节蛋白和重金属解毒所奠定的知识基础。这些目标将有助于深入了解金属配位和肽链结构之间的相互作用，从而确定整个金属肽折叠，这是金属肽设计的一个重要方面。公共卫生相关性：与人类健康相关的重金属，如PbII、HgII、AsII和CdII，由于其急性毒性和慢性暴露的长期影响(例如，美国环保署在2002年估计，美国有超过30万儿童的血液水平超过10g/dL)，导致严重的健康问题。我们的研究通过多种方式解决了这些问题：包括模拟蛋白质中的重金属结合部位，以了解重金属如何与蛋白质结合，定义反应发生的速率，以及建立这些金属对不同部位的热力学偏好。我们还将这项工作与用于识别或解毒细菌、真菌和人类中的重金属的蛋白质的研究联系起来(例如，评估HgII如何与人类铜伴侣HAH1相互作用)。