COUPLED METAL BINDING-PROTEIN FOLDING REACTIONS

大约三分之一的蛋白质与金属离子结合。 在许多生物过程中起着至关重要的作用， 能量的储存和传导、基因调控和新陈代谢。 在 为了使这些蛋白质发挥其应有的功能，它们必须 选择性地结合它们的同源金属离子。 这种承认过程有 一般被认为是由简单的， 受控制的结合反应 越来越多的证据显示 动力学因素的重要性。 金属结合动力学 和交换反应尚未被广泛研究。 的 金属结合反应的热力学和动力学似乎是 受结构程度的显著影响， 蛋白质去除金属离子。 的热力学和动力学 金属结合，释放和交换反应将研究一系列 不同的蛋白质在这些结构特征方面。 仅在金属结合时诱导蛋白质折叠的系统提供 研究金属结合和蛋白质的独特机会 折叠过程 这些研究将使用一种 叫做锌指肽。 待研究的蛋白质折叠方面 包括不同氨基酸采用的热力学倾向 β折叠、α螺旋和其他结构。 获得的数据将 根据基于结构的热力学分析模型解释 它是为研究其他蛋白质的折叠和结合而开发的 反应. 最后，调节金属结合亲和力的能力， 蛋白质折叠能量的变化将被用来产生 用于监测锌和其它金属离子的肽传感器系列 浓度通过荧光的变化。

Approximately one third of all protein bind metal ions.Such metalloproteins play crucial roles in a large number of biological processes including the storage and transduction of energy, gene regulation, and metabolism. In order for these proteins to achieve their proper functions, they must selectively bind their cognate metal ions. Such recognition processes have been generally assumed to be governed by simple, thermodynamically controlled, binding reactions. Evidence has been accumulating revealing the importance of kinetic factors as well. The kinetics of metal binding and exchange reactions have not been extensively studied. The thermodynamics and kinetics of metal binding reactions appear to be significantly affected by the degree of structure that remains in the protein upon removal of the metal ion. The thermodynamics and kinetics of metal binding, release, and exchange reactions will be studied for a series of protein that differ in terms of these structural characteristics. Systems for which protein folding is induced only upon metal binding offer unique opportunities for investigating both metal binding and protein folding processes. Such studies will be performed with the use of a so- called zinc finger peptide. Aspects of protein folding to be investigated include the thermodynamic propensities for different amino acids to adopt beta sheet, alpha helix, and other structures. The data obtained will be interpreted in terms of a structure-based thermodynamics analysis model that has been developed for studies of other protein folding and binding reactions. Finally, the ability to modulate metal binding affinity through variations in protein folding energies will be utilized to generate a series of peptide sensors to be used to monitor zinc and other metal ion concentrations via changes in fluorescence.