Mechanistic studies of thioether crosslink formation in peptides

肽中硫醚交联形成的机理研究

• 批准号: 9169902
• 负责人: VAHE BANDARIAN
• 金额: $ 28.7万
• 依托单位: UNIVERSITY OF UTAH
• 依托单位国家: 美国
• 财政年份: 2016
• 资助国家: 美国
• 起止时间: 2016-08-01 至 2020-07-31
• 项目状态: 已结题
• 来源: https://reporter.nih.gov/project-details/9169902
• 关键词: Active Sites; Address; Adoption; Anabolism; Anti-Bacterial Agents; Antineoplastic Agents; Antiviral Agents; Area; Binding; Biochemical; Carbon; Catalysis; Cells; Chemistry; Cleaved cell; Clinic; Cysteine; Electron Spin Resonance Spectroscopy; Electrons; Engineering; Enzymatic Biochemistry; Enzymes; Family; Future; Goals; Housing; Label; Lead; Life; Mediating; Methionine; Methods; Modification; Molecular; Mutation; Natural Products; Outcome; Oxidation-Reduction; Pathway interactions; Peptide Synthesis; Peptides; Play; Post-Translational Protein Processing; Property; Protein Family; Publishing; Reaction; Reporting; Research; Roentgen Rays; Role; Site; Structure; Structure-Activity Relationship; Sulfur; System; Therapeutic Agents; Therapeutic Uses; Time; Variant; base; cofactor; crosslink; enzyme mechanism; insight; killings; member; novel; oxidation; peptide synthase; polypeptide; quorum sensing; reconstitution; spectroscopic survey; thioether; tool

PROJECT SUMMARY All domains of life produce peptidic natural products that play roles as diverse as quorum sensing molecules and redox cofactors. The ability of these peptides to function as antibacterial, antiviral, or anticancer agents makes understanding their biosynthesis an important area of contemporary research. Peptide-based secondary metabolites are produced by distinct biosynthetic pathways that differ in whether the peptide is synthesized by the action of non-ribosomal peptide synthetases (NRPS), or ribosomally produced from a genomically encoded orf. These peptides are often extensively modified. While in the NRPS systems many of the modifications occur concurrently with peptide synthesis, the ribosomally encoded peptides undergo posttranslational modification. These so-called ribosomally encoded posttranslationally modified polypeptides (RiPP) are a new emerging class of polypeptides that have extensive modifications that are introduced by mechansims that are mostly poorly understood. This application will focus on enzymes introduce sulfur-to-alpha carbon thioether crosslinks into ribosomally encoded peptides to produce sactipeptides. These linkages are distinct from the well-studied lanthipeptide, where thioether crosslinks form between a Cys residue and a dehydrated Thr/Ser. The sactipeptide maturases are members of the radical SAM family of enzymes and catalyze thioether crosslinks by a radical- mediated reaction that is not understood. While The biochemical, spectroscopic, and structural studies in this application will lead to a mechanistic paradigm for this important class of enzymes. While sactipeptides themselves have various therapeutic uses, understanding the substrate profiles and mechanisms of these enzymes would provide a tool for synthesis of crosslinked peptides, which are increasing finding utility in the clinic.

项目概要 生命的所有领域都会产生肽类天然产物，其作用与群体一样多样化 传感分子和氧化还原辅助因子。这些肽发挥作用的能力 抗菌剂、抗病毒剂或抗癌剂使了解其生物合成变得更加容易 当代研究的重要领域。基于肽的次级代谢产物是 由不同的生物合成途径产生，这些途径的不同在于肽是否是 通过非核糖体肽合成酶（NRPS）的作用合成，或核糖体 由基因组编码的 orf 产生。这些肽通常广泛 修改的。在 NRPS 系统中，许多修改同时发生 肽合成时，核糖体编码的肽经历翻译后 修改。这些所谓的核糖体编码的翻译后修饰 多肽（RiPP）是一类新兴的多肽，具有广泛的应用前景。 由大多数人知之甚少的机制引入的修改。 该应用将重点关注将硫引入α碳硫醚的酶 交联成核糖体编码的肽以产生 sacipeptides。这些联系 与经过充分研究的羊毛硫肽不同，羊毛硫肽之间形成硫醚交联 一个半胱氨酸残基和一个脱水的苏氨酸/丝氨酸。 sacipeptide 成熟酶是以下成员 自由基 SAM 酶家族并通过自由基催化硫醚交联 介导的反应尚未被理解。而生化、光谱和 该应用中的结构研究将为这一重要的机制带来机械范式 酶类。虽然活性肽本身具有多种治疗用途， 了解这些酶的底物概况和机制将提供 合成交联肽的工具，其在临床中的实用性日益增加。