ELECTRON TRANSFER MECHANISMS IN REACTION CENTERS

反应中心的电子传输机制

• 批准号: 2180670
• 负责人: PETER LESLIE DUTTON
• 金额: $ 19.98万
• 依托单位: UNIVERSITY OF PENNSYLVANIA
• 依托单位国家: 美国
• 财政年份: 1989
• 资助国家: 美国
• 起止时间: 1989-02-01 至 1998-01-31
• 项目状态: 已结题
• 来源: https://reporter.nih.gov/project-details/2180670
• 关键词: Rhodopseudomonas; X ray crystallography; bacterial proteins; bioenergetics; chlorophyll; coulometry; crystallization; cytochrome c; cytochrome oxidase; electric field; electrochemistry; electron transport; flash photolysis; heme; hydropathy; molecular energy level; molecular film; photosynthetic bacteria; photosynthetic reaction centers; protein engineering; protein structure function; site directed mutagenesis; spectrometry; synthetic peptide; thermodynamics

It is now well known that the central function of the bioenergetic machinery of respiratory and photosynthetic membranes is to convert the free energy between oxidants and reductants into a transmembrane electrical potential and a proton gradient, and that this drives essential energy requiring processes of ion and metaholite transport and ATP production. A challenge is to understand how electron transfers are controlled in these membrane proteins that are crowded with highly reactive intermediates. The aim of the proposed experimental work is to determine the fundamental principles of molecular design and engineering that are responsible for the governance of the rates and directional specificity of electron transfers through protein directed across bioenergetic membranes. The Langmuir-Blodgett film balance and self-assembled monolayers will be used to manipulate the proteins into a vectorial configuration that facilitates structure determination and ready investigation of charge separating events. These assemblies will be used to monitor, modulate and activate charge separating events in respiratory and photosynthetic redox proteins. A second approach will develop novel synthetic constructions of protein and cofactors, designed and engineered to provide minimal water soluble structures that perform critical functions of the native protein. It is hoped in the long term that these synthetic redox proteins will access problems difficult, if not impossible, with the membrane proteins, including offering a simpler path towards crystallization and structural resolution of the active parts of their natural counterparts. In describing the engineering parameters of electron transfer driven charge separation, the regions of normal efficient operation will be identified. Recognition of the functional tolerances, therefore, define the threshold of dysfunction that underlies pathological conditions.

现在众所周知，生物能量的核心功能 呼吸膜和光合膜的机制是将 氧化剂和还原剂之间进入跨膜的自由能 电势和质子梯度，这驱动了必要的 离子和代谢物运输以及 ATP 需要能量的过程 生产。一个挑战是了解电子转移是如何进行的 这些膜蛋白受到控制，这些膜蛋白挤满了高度 反应中间体。拟议实验工作的目的是 确定分子设计和工程的基本原理 负责利率和方向的治理 通过蛋白质定向电子转移的特异性 生物能膜。 Langmuir-Blodgett 薄膜平衡和自组装单层膜将 用于将蛋白质操纵成矢量构型 促进结构确定和电荷调查 分离事件。这些组件将用于监控、调节和 激活呼吸和光合作用氧化还原中的电荷分离事件 蛋白质。第二种方法将开发新型合成结构 蛋白质和辅因子，经过设计和工程设计，可提供最少的水 执行天然蛋白质关键功能的可溶性结构。 从长远来看，希望这些合成的氧化还原蛋白能够 膜蛋白的访问问题即使不是不可能，也是很困难的， 包括提供更简单的结晶和结构途径 其天然对应物的活性部分的解析。 在描述电子转移驱动的工程参数时 电荷分离，正常有效运行的区域将是 确定。因此，识别功能公差，定义 病理状况下的功能障碍阈值。