XAS ELECTRONIC AND GEOMETRIC STRUCTURE STUDIES ON CU CONTAINING METALLOPROTEINS

这个子项目是许多研究子项目中利用 资源由NIH/NCRR资助的中心拨款提供。子项目和 调查员(PI)可能从NIH的另一个来源获得了主要资金， 并因此可以在其他清晰的条目中表示。列出的机构是 该中心不一定是调查人员的机构。 我们建议扩展我们以前在生物学中对铜中心的研究，使用S K-、铜L-和铜K-EDGE和EXAFS光谱相结合的方法来确定参与电子转移、O2活化、N2O还原和辅因子生物发生的含铜蛋白质的电子结构和几何结构。我们计划研究蓝铜蛋白的氢键突变体，以评估电子结构的变化及其对BC蛋白ET性质的影响。用铜K边EXAFS研究了不同pH下还原形式的CuA-S，考察了pH对中心的ET和质子泵浦性质的影响。我们还计划研究参与氧结合、转运和激活的单核、双核和多核铜和血红素-铜蛋白的模型络合物，以了解氧相互作用和激活的机制。该模型研究将扩展到相关的蛋白质系统，以阐明O2结合的结构/功能相关性以及独特的蛋白质活性位点的激活。

This subproject is one of many research subprojects utilizing the resources provided by a Center grant funded by NIH/NCRR. The subproject and investigator (PI) may have received primary funding from another NIH source, and thus could be represented in other CRISP entries. The institution listed is for the Center, which is not necessarily the institution for the investigator. We propose to extend our previous studies on copper sites in biology, using a combination of S K-, Cu L-, and Cu K-edge and EXAFS spectroscopies, to define the electronic and geometric structure of Cu-containing proteins involved in electron transfer, O2 activation, N2O reduction and cofactor biogenesis. We plan to study H-bonding mutants of blue-copper proteins to evaluate the changes in electronic structure and its effect on the ET properties of BC proteins. A Cu K-edge EXAFS study will be performed on the reduced form of CuA at different pH?s to investigate the effect of pH on the ET and proton-pumping properties of the site. We also plan to study model complexes of mononuclear, binuclear, and multinuclear Cu and Heme-Cu containing proteins that are involved in O2 binding, transport and activation to understand mechanistic pathways of O2 interaction and activation. The model study will be extended and correlated to relevant protein systems to shed light on structure/function correlation of O2 binding and activation by the unique protein active sites.