MOLECULAR & CONTROL MECHANISM OF ENERGY COUPLING SITE I

我们建议研究电子和质子转移的机制 线粒体NADH-醌氧化还原酶途径（通常称为 作为复合物I）。 这种复合物在氧化中起着中心作用， NADH，细胞代谢的还原产物，通过呼吸道 链 复合体I是最复杂也是最不被理解的能量 转导呼吸链的质子动力酶。 拟议 研究在机理的调查中采取了新的方向， 动力学和调节特性的这种复杂的两个孤立的 和膜结合状态。 具体研究内容包括：[I] 确定能够催化的络合物I的最小结构 与质子跨膜的矢量转移耦合的NADH氧化 膜; [II]测定内部电子转移 NADH-醌氧化还原酶内在氧化还原组分内的序列 利用人工电子受体（过渡金属络合物） 具有适当的氧化还原电位和适当的其它参数 （亲水性，电荷，尺寸）; [III]对 与复合物I中的特异性结合位点相关的泛醌 最近在俄罗斯的Co-P.I.的实验室; [IV] 慢活性/非活性细胞中分子事件的研究 最近由俄罗斯Co-P.I.重新发现的复合体I的过渡， 这将扩展到生理相关因素的搜索 它们参与了该复合体的滞后行为的控制。 私家侦探具有丰富的EPR研究经验， 分析线粒体和线粒体膜的固有顺磁性氧化还原中心， 微生物系统 特别是私家侦探取得了重大 在铁硫簇合物、黄素和 泛醌自由基 俄罗斯Co-P.I.是一个既定 生物化学家，最近开发了独特的亚线粒体颗粒 具有紧密偶联位点I能量转导的制剂。 的 因此，这些研究人员之间的合作计划，预计 大大提高了对能量耦合机制的理解， 及其监管。

We propose to study the mechanism of electron and proton transfer pathways in mitochondrial NADH-quinone oxidoreductase (often referred to as Complex I). this complex plays a central role in the oxidation of NADH, the reducing product of cellular metabolism, by the respiratory chain. Complex I is the most complicated and least understood energy transducing proton-motive enzyme of the respiratory chain. the proposed research takes new directions in the investigation of the mechanism, kinetics, and regulatory properties of this complex in both the isolated and membrane-bound states. The specific studies will include: [I] determination of the minimal structure of Complex I capable of catalyzing NADH oxidation which is coupled with vectorial transfer of protons across the membrane; [II] determination of the internal electron transfer sequence within intrinsic redox components of NADH-quinone oxidoreductase by utilizing artificial electron acceptors (transition metal complexes) with proper redox potentials and appropriate other parameters (hydrophilicity, charge, size); [III] physico-chemical studies on the ubisemiquinones associated with the specific binding sites in Complex I which was recently discovered in Russian Co-P.I.'s laboratory; [IV] studies of molecular events involved in the slow active/inactive transition of Complex I, rediscovered recently by the Russian Co-P.I., which will be extended to searches of physiologically relevant factors which are involved in the control of hysteretic behavior of this complex. The P.I. has extensive experience with EPR studies and with thermodynamic analysis of the intrinsic paramagnetic redox centers of mitochondrial and microbial systems. Specifically, the P.I. has made significant contribution in the characterization of iron-sulfur clusters, flavin and ubiquinone free radicals. The Russian Co-P.I. is an established biochemist and has recently developed unique submitochondrial particle preparations having tightly coupled Site I energy transduction. The collaborative program between these investigators, therefore, is expected to greatly enhance the understanding of the mechanism of energy coupling and its regulation.