Structural Basis of Metallocofactor Delivery and Repair

金属辅因子传递和修复的结构基础

• 批准号: 10318598
• 负责人: Francesca Vaccaro
• 金额: $ 4.68万
• 依托单位: MASSACHUSETTS INSTITUTE OF TECHNOLOGY
• 依托单位国家: 美国
• 财政年份: 2020
• 资助国家: 美国
• 起止时间: 2020-01-01 至 2023-12-31
• 项目状态: 已结题
• 来源: https://reporter.nih.gov/project-details/10318598
• 关键词: Binding; Biological Models; Chemistry; Chimeric Proteins; Cobalamin; Coenzymes; Complex; Crystallization; Data; Disease; Electron Microscopy; Electron Spin Resonance Spectroscopy; Electrons; Enzymes; Excision; GTP-Binding Protein alpha Subunits, Gs; GTP-Binding Proteins; Guanosine Triphosphate; Guanosine Triphosphate Phosphohydrolases; Health; Human; Hydrolysis; Laboratories; Lead; Length; Mediating; Metabolism; Methylmalonyl-CoA Mutase; Methylobacterium extorquens; Molecular; Molecular Chaperones; Molecular Conformation; Molecular Mechanisms of Action; Molecular Sieve Chromatography; Mutase; Mutation; Negative Staining; Nucleotides; Pathway interactions; Play; Process; Proteins; Roentgen Rays; Role; Sampling; Spin Labels; Structure; Substrate Domain; System; Tertiary Protein Structure; Three-Dimensional Image; Time; Vitamin B 12; Work; X-Ray Crystallography; analog; biophysical techniques; cobamamide; cofactor; human disease; image reconstruction; insight; isobutyryl-coenzyme A; methylmalonic aciduria; polypeptide; protein activation; protein complex; repaired

PROJECT SUMMARY/ABSTRACT Complex and reactive metallocofactors are often responsible for challenging chemistry that is critical to cellular metabolism. It is therefore not surprising that the transport of these cofactors to their target enzymes often involves multiple proteins and complex delivery pathways. Mutations in any of these components may result in a breakdown of the pathway causing deficits in the overall activity of the target enzyme and leading to a disease state, as in the case with the vitamin B12 (cobalamin, Cbl) delivery pathway. In this proposal, we will study enzymes from humans, Methylobacterium extorquens and Cupriavidus metallidurans in order to determine the molecular mechanisms of Cbl transport and installation. Our approach involves the use of a variety of biophysical methods that will allow us to visualize the interactions between a G-protein chaperone and its target Cbl- dependent mutase in the final step of the Cbl delivery pathway. This work will inform on the structural basis of chaperone-mediated delivery and repair of Cbl. By combining X-ray crystallography, electron microscopy and electron paramagnetic resonance spectroscopy, we will explore the molecular mechanism of action of the G- protein chaperones involved in the installation and repair of adenosylcobalamin in their target mutases.

项目概要/摘要 复杂且反应性的金属辅因子通常负责对细胞至关重要的具有挑战性的化学反应 代谢。因此，这些辅因子经常转运至其靶酶也就不足为奇了。 涉及多种蛋白质和复杂的传递途径。这些成分中任何一个的突变都可能导致 途径的破坏导致目标酶的整体活性缺陷并导致疾病 状态，就像维生素 B12（钴胺素，Cbl）输送途径的情况一样。在本提案中，我们将研究 来自人类、扭断甲基杆菌和金属铜的酶，以确定 Cbl 运输和安装的分子机制。我们的方法涉及使用各种生物物理方法 使我们能够可视化 G 蛋白伴侣与其目标 Cbl- 之间的相互作用的方法 Cbl 传递途径最后一步的依赖变位酶。这项工作将提供结构基础 分子伴侣介导的 Cbl 传递和修复。通过结合 X 射线晶体学、电子显微镜和 电子顺磁共振波谱，我们将探索G-作用的分子机制 蛋白质伴侣参与腺苷钴胺素在其目标变位酶中的安装和修复。