A Biosynthetic Approach Toward Biomimetic Studies of Metalloproteins Involved in Long-range Electron Transfer

伊利诺伊大学香槟分校的Yi Lu教授的这项研究得到了无机，生物无机和有机化学项目的支持。 这项工作的目标是阐明人工引入的双铜，铜-A，在天青蛋白，其中，在自然界中，包含一个单核铜网站中心的每个配体的作用。 这将能够确定配体对Cu-A中心的几何参数、电子结构和行为的影响，这对重要的电荷转移蛋白质（如细胞色素氧化酶）的功能是必不可少的。 此外，本研究提供了三个重要的电子转移中心的结构和功能特性的直接比较：蓝色（1型）铜，Cu-A和Fe 2S 2。 通过一种新的技术，表达蛋白连接（EPL），将二铁中心插入天青蛋白中，该技术有望成为一种非常有效和成本效益高的方法来产生毫克量的含有非天然氨基酸的蛋白质。电子转移蛋白质对基本生命过程至关重要。 将系统地确定围绕人工放置在该蛋白质中的不寻常的Cu-A位点的各种氨基酸的影响，并与正常的蓝色铜位点和另一个双金属位点Fe 2S 2进行比较，Fe 2S 2也发生在必需的电子转移蛋白质中。

This research by Professor Yi Lu of the University of Illinois at Urbana-Champaign is supported by the Inorganic, Bioinorganic and Organometallic Chemistry program. The goal of this work is to elucidate the role of each ligand of an artificially introduced dicopper, Cu-A, center in azurin, which, in nature, contains a mononuclear copper site. This will enable determining ligand effects on geometric parameters, electronic structure and behavior of the Cu-A center, which are essential to the function of important charge-transfer proteins, such as cyctochrome oxidase. In addition, this study provides for the direct comparison of the structural and functional properties of three important electron transfer centers: blue (type 1) copper, Cu-A and Fe2S2. The di-iron center will be inserted into the azurin by a new technique, expressed protein ligation (EPL), which shows promise as a very efficient and cost-effective way to generate milligram quantities of proteins containing unnatural amino acids.Electron-transfer proteins are vital to fundamental life processes. The effects of the various amino acids surrounding the unusual Cu-A site artificially placed in this protein will be systematically determined and compared with that of the normal blue copper site and another two-metal site, Fe2S2, which also occurs in essential electron-transfer proteins.