NOVEL 199HG NMR METHODS FOR MONITORING PROTEIN FOLDING

描述：（改编自申请人的摘要）蛋白质折叠异常与越来越多的人类疾病有关。由于难以监测折叠过程中的特定相互作用，在原子水平上对这些异常的起源进行表征受到阻碍。核磁共振波谱是为数不多的用于蛋白质折叠研究的技术之一，它可以提供原子水平上的信息。由于蛋白质中含有丰富的核磁共振活性质子，因此产生的基于质子的核磁共振光谱很少是完全可分辨的。需要辅助因子进行折叠的一类蛋白质提供了通过监测辅助因子的核磁共振信号来研究折叠过程的机会。本文将重点研究199Hg作为金属蛋白折叠探针的应用。将开发二维{1H-199Hg} NMR方法来突出折叠过程中的生物分子相互作用。这些研究还将为研究环境暴露于汞和某些其他金属的病理学提供新的工具。x射线晶体学方法将用于确定不同的汞（II）配位化合物库的结构，使用合成的配体模型的蛋白质金属结合位点。该库将扩展我们对199Hg化学位移的生物学相关结构-光谱关系以及溶液和固态中199Hg和1H之间的耦合常数的知识。将制备具有良好核磁共振性质的其他过渡金属的同构配合物，以系统地比较它们作为金属生物探针的相对优点。最后，将利用x射线晶体学和核磁共振技术研究各种潜在金属配位环二肽的Hg（II）配位化学，作为这些新技术应用于金属蛋白的前奏曲。

DESCRIPTION: (Adapted from the applicant's abstract) Abnormalities in protein folding are associated with a growing list of human diseases. Characterization of the origin of these abnormalities at the atomic level is hindered by difficulties in monitoring specific interactions during the folding process. Nuclear magnetic resonance (NMR) spectroscopy is one of the few techniques employed for the study of protein folding that can provide information at the atomic level. Because proteins are very rich in NMR-active protons, the resulting proton-based NMR spectra are rarely fully resolvable. The class of proteins that require cofactors for folding provide an opportunity to study the folding process by monitoring the NMR signal of the cofactor. The proposed work will focus on the use of 199Hg as a probe of metalloprotein folding. Two-dimensional {1H-199Hg} NMR methods will be developed to highlight the biomolecular interactions during the folding process. These studies will also provide a new tool for investigating the pathology of environmental exposure to mercury and certain other metals. X-ray crystallographic methods will be employed to determine the structures of a diverse library of Hg(II) coordination compounds using synthetic ligand models of protein metal-binding sites. This library will extend our knowledge of biologically relevant structure-spectroscopy relationships for 199Hg chemical shifts and coupling constants between 199Hg and 1H in solution and the solid state. Isostructural complexes of other transition metals with favorable NMR properties will be prepared to initiate a systematic comparison of their relative merits as metallobioprobes. Finally, the Hg(II) coordination chemistry of a variety of potentially metal-coordinating cyclic dipeptides will be examined using X-ray crystallography and NMR as a prelude to the application of these new techniques to metalloproteins.