MOLECULAR STRUCTURE OF N-ACETYL CYSTEINE METAL COMPLEXES

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。 N-乙酰-L-半胱氨酸是一种天然抗氧化剂，可提高螯合剂抗重金属中毒的效率，促进铬、镉、铅的排泄，但不促进汞的排泄。最近的生物实验表明，过渡金属(锌、钴、钴、铁)与NaC形成的络合物具有显著的抗炎活性。本研究的目的是在不同的[NAc]/[Mn+]比和[Mn+]=10和100 mM的条件下，研究生理pH和pH=8.5的固态和水溶液中NAc与重金属和过渡生物金属的络合物的结构。在本研究中，我们将结合不同光谱技术的结果，如扩展X射线吸收精细结构(EXAFS)、多核核磁共振、拉曼光谱和红外光谱，来鉴定这些配合物中中心金属离子周围的局域结构。我们将使用我们开发的方法来分析类似的Cd(II)、Hg(II)和Pb(II)与半胱氨酸和青霉胺(3，3‘-二甲基半胱氨酸)的混合物的EXAFS数据，包括EXAFS光谱的主成分分析(PCA)。本研究的目的是为更好地了解半胱氨酸衍生物作为络合物形成剂的解毒治疗和抗炎活性提供基础。

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. N-acetyl-L-cysteine (NAC), a natural antioxidant, improves the efficiency of chelating agents used against heavy metal poisoning and facilitates the excretion of Cr(III), Cd(II) and Pb(II), but not of Hg(II). Recent bio-tests on NAC complexes with transition biometals (Zn2+, Co2+, Co3+, Fe2+) showed significant anti-inflammatory activity. The goal of our proposed research is to study the structure of NAC complexes with heavy metals, and transition biometals, in solid state and in aqueous solution at physiological pH and pH = 8.5, using different [NAC]/[Mn+] ratios and [Mn+] = 10 and 100 mM. In this study, we will combine the results from different spectroscopic techniques, such as extended x-ray-absorption fine structure (EXAFS), multi-nuclear NMR, Raman and IR, to identify the local structure around the central metal ion in these complexes. We will use the method that we have developed for EXAFS data analysis of mixtures for similar Cd(II), Hg(II) and Pb(II) complexes with cysteine and penicillamine (3,3'-dimethyl cysteine), including Principal Component Analysis (PCA) of the EXAFS spectra. The aim of the current study is to provide a basis for better understanding of the detoxification treatments and the anti-inflammatory activities with the use of cysteine derivatives as complex-forming agents.