CONTROLLING THE REDOX CHEMISTRY OF FLAVINS

描述：(首席调查员)本提案描述了 黄素酶催化模型的设计、合成和物理研究。 具体地说，我们将探索构象、取代基和 氢键对黄素氧化还原性质的影响。我们建议 合成具有内在构象偏向的黄素；通过设计 这样的模型，我们可以分离出构象对黄素氧化还原的作用 化学反应。充分认识构象在黄素氧化还原中的作用 属性，我们还必须确定电子的影响 黄素苯亚核上的取代。这将是 通过在C6-C9上合成具有各种取代基的黄素来完成的 并考察它们对还原电位的影响。 有人认为黄素核与蛋白质之间的氢键 主链可以影响辅因子的几何结构和氧化还原性质。 除了构象偏向的黄素，我们还将 能为N1和N5提供特定氢键的合成模型 黄素。探索合作氢影响的Flavin模型 债券网络也将被研究。所有的黄素模型都将由 循环伏安法在水溶液和非水介质中的应用 动力学方法。

DESCRIPTION: (Principal Investigator's) This proposal describes the design, synthesis and physical study of models for flavoenzyme catalysis. Specifically, we will explore the role of conformation, substituents and hydrogen bonding on the redox properties of flavins. We propose to synthesize flavins which have build-in conformational biases; by designing such models, we can isolate the role of conformation on the flavin redox chemistry. To fully understand the role of conformation on flavin redox properties, we must also determine the electronic influence of substitution on the benzene subnucleus of flavins. This will be accomplished by synthesizing flavins with various substituents at C6-C9 and examining their influence on reduction potential. It is proposed that hydrogen bonding of the flavin nucleus to the protein backbone can influence the geometry and redox properties of the co-factor. In addition to the conformationally biased flavins, we will also synthesize model which can provide specific hydrogen bonds to N1 and N5 of flavins. Flavin models that explore the influence of cooperative hydrogen bond networks will also be studied. All flavin models will be studied by cyclic voltammetry in aqueous buffer as well as non-aqueous media and by kinetic methods.