Spectroscopic and Magnetic Studies of Metalloprotein Active Sites

偶联双核非血红素铁活性位点存在于多种具有不同生物学功能的蛋白质中。甲氰菊酯（Hr）与O2结合，甲烷单加氧酶激活其羟基化，还原核糖核苷酸还原酶与O2反应生成具有催化活性的酪氨酸自由基，还原紫色酸性磷酸酶在磷酸盐存在下氧化失活。这些蛋白质位点（和类似的模型复合物）可以在三种氧化态下得到。Solomon博士对这些位点及其底物和小分子结合形式的光谱研究强调吸收、圆二色性和磁性圆二色性（MCD）来探测激发态，以及变温度、变场MCD来探测基态亚能级分裂。这些数据可以确定每个铁的几何形状，以及与桥接连接相关的交换耦合。本研究的目的是确定与生物反应性变化相关的活性位点几何和电子结构差异。

A coupled binuclear non-heme iron active site exists in a variety of proteins which perform different biological functions. hemerythrin (Hr) binds O2, methane monooxygenase activates it for hydroxylation, reducted ribonucleotide reductase reacts with O2 to generate a catalytically active tyrosyl radical, and reduced purple acid phosphatase is oxidatively inactivated in the presence of phosphate. These protein sites (and analogous model complexes) can be obtained in three oxidation states. Dr. Solomon's spectral studies on these sites and their substrate and small molecule bound forms emphasize bsorption, circular dichrosims, and magnetic circular dichroism (MCD) to probe the excited states, and variable- temperature, variable-field MCD to probe ground state sublevel splittings. This data enables a determination of the geometry of each iron, and the exchange coupling which is associated with bridging ligation. The goal of this research is to define active site geometric and electronic structural diffeences which correlate with variation in biological reactivity.