Conformations of c-type cytochrome self-assembling complexes

c型细胞色素自组装复合物的构象

• 批准号: 7626695
• 负责人: Kristy Lynn Mardis
• 金额: $ 6.46万
• 依托单位: CHICAGO STATE UNIVERSITY
• 依托单位国家: 美国
• 财政年份: 2008
• 资助国家: 美国
• 起止时间: 2008-06-01 至 2011-05-31
• 项目状态: 已结题
• 来源: https://reporter.nih.gov/project-details/7626695
• 关键词: Agreement; Air Pollution; Amino Acids; Architecture; Articular Range of Motion; Binding; Biological; Biological Models; Catalysis; Catalytic Domain; Chemicals; Code; Complex; Coupled; Cytochrome c Group; Cytochromes; DNA Sequence; Data; Databases; Devices; Electric Wiring; Electron Transport; Environment; Escherichia coli; Fossil Fuels; Genome; Genomics; Geobacter; Goals; Heme; In Situ; Investigation; Link; Mediating; Modeling; Molecular Conformation; Molecular Models; Motion; Organism; Pattern; Phase; Photosynthesis; Pilot Projects; Process; Protein Conformation; Protein Dynamics; Proteins; Public Health; Reaction; Resolution; Respiration; Respiration Disorders; Respiratory Chain; Respiratory Process; Roentgen Rays; Role; Solar Energy; Solutions; Structure; System; Techniques; Testing; Time; Vertebral column; Work; aqueous; base; cytochrome c; cytochrome c oxidase; cytochrome c(3); design; dimer; improved; insight; link protein; macromolecule; microbial; mimetics; molecular dynamics; molecular modeling; nanoscale; overexpression; protein complex; small molecule

DESCRIPTION (provided by applicant): Electron transfer (ET) reactions are crucial for a wide range of biologically important processes including photosynthesis and respiration. In photosynthesis and respiration, ET reactions require an organized assembly of proteins. Our long-term goal is to determine the role of protein conformation on ET. This requires the construction and investigation of model supramolecular assemblies capable of ET. Our hypothesis is that c-type cytochromes will provide such a model system. We base this hypothesis on three observations: (1) they are involved in the respiratory processes of almost all organisms, (2) some can self-assemble into chains, and (3) they are capable of electron transfer when bound to certain small molecules. Multi-domain c-cytochromes have applications as components in bio-mimetic energy storage devices as electric wires or catalytic sites. Detailed structural information about these supramolecular architectures would provide insight into the role of conformation in ET reactions and their suitability as ET agents. To resolve the structure of these complexes in their biological environment (aqueous solutions) wide-angle X-ray scattering techniques are employed. However, this technique requires the construction of molecular models to interpret the experimental data. Hence, the specific goal of the proposed work is to use molecular dynamics to create such models, calculate their X-ray scattering patterns, and by comparison to the experimental data, provide an atomic level picture of c-type cytochrome complexes. In this pilot project, we will: (1) elucidate the structure of di-, tri-, and tetramers of cytochrome c7 by construction of conformation models via solution phase molecular dynamics calculations and comparison of the calculated and experimental scattering data; (2) acquire sufficient data to allow submission of a SC1-type proposal. Successful completion of this work will illuminate the role of conformation in ET and the suitability of cytochrome c7 complexes as building blocks for energy storage devices. Relevance to Public Health: The current study focuses on evaluating a self-assembling system that has been proposed as a new solar energy storage device. More efficient solar energy systems would allow a reduction in fossil fuel usage which, due to its contribution to air pollution, has been linked to increasing respiratory disorders.

描述（由申请人提供）：电子转移（ET）反应对于包括光合作用和呼吸在内的各种重要的生物学过程至关重要。在光合作用和呼吸作用中，ET 反应需要蛋白质的有组织的组装。我们的长期目标是确定蛋白质构象对 ET 的作用。这需要构建和研究能够进行 ET 的模型超分子组装体。我们的假设是 c 型细胞色素将提供这样的模型系统。我们的这一假设基于三个观察结果：（1）它们参与几乎所有生物体的呼吸过程，（2）一些可以自组装成链，（3）它们在与某些小分子结合时能够进行电子转移。多域c-细胞色素可作为仿生储能装置的组件（如电线或催化位点）应用。有关这些超分子结构的详细结构信息将有助于深入了解构象在 ET 反应中的作用及其作为 ET 剂的适用性。为了解析这些复合物在其生物环境（水溶液）中的结构，采用了广角 X 射线散射技术。然而，该技术需要构建分子模型来解释实验数据。因此，该工作的具体目标是利用分子动力学创建此类模型，计算其 X 射线散射图案，并通过与实验数据进行比较，提供 c 型细胞色素复合物的原子水平图片。在该试点项目中，我们将：（1）通过溶液相分子动力学计算以及计算和实验散射数据的比较，构建构象模型，阐明细胞色素c7二聚体、三聚体和四聚体的结构； (2) 获取足够的数据以允许提交 SC1 类型提案。这项工作的成功完成将阐明构象在 ET 中的作用以及细胞色素 c7 复合物作为能量存储设备构建模块的适用性。 与公共健康的相关性：当前的研究重点是评估一种自组装系统，该系统已被提议作为一种新型太阳能存储装置。更高效的太阳能系统将减少化石燃料的使用，因为化石燃料会造成空气污染，并与呼吸系统疾病的增加有关。