BIOLOGICAL CHEMISTRY OF SULFUR AND SELENIUM

建议研究硫醇中硫的生物化学。 和二硫化物形式，以及硒醇和二硒醚形式的硒。 这项研究的长期目标是表征化学物质 硫磺和硫的生物化学的中心反应 硒，但还没有被定量表征，因为 缺乏实验方法。反应的特征将在 测定完整红细胞、血浆和水溶液中的分子水平 核磁共振波谱。此外，敏感的和选择性的方法基于高 高效液相色谱-电化学检测 将被开发并用于研究硫醇的生物化学 以及血浆和红细胞中的二硫化物。 完整红细胞中硫醇和二硫化物的研究将是 设计用来表征细胞内硫醇/二硫化物化学 氧化应激状态。体内的红细胞是有规律的 承受氧化应激和存在氧化应激的条件 不同的疾病状态。拟议的研究将使用 无创性~1H-核磁共振方法表征细胞内动力学 内源硫醇和含硫硫醇的硫醇/二硫化学 处于氧化应激状态的红细胞中的药物分子 随着它们的细胞内区域恢复到更正常的还原 条件。将使用高效液相色谱方法检测在 在这些条件下的痕量水平，包括血红蛋白-小分子 混合二硫化物。天然硒醇和二硒醚的化学组成 红细胞将用同样的技术进行研究，目的是 以这些形式表征硒的细胞内化学。 关于氧化还原化学的新的基本信息 氨基酸、多肽、蛋白质和药物分子中硫的含量 从硫醇/二硫化物的动力学和平衡研究中获得 水溶液中的交换反应。该研究将包括 蛋白质-小分子混合二硫化物的研究 参与不同的过程，如同型半胱氨酸尿症和药物诱导 超敏反应与多肽激素中二硫键的研究 如加压素和催产素。的动力学和平衡点 硫醇与二硒醚和硒基硫化物的反应也将被 具有特征的，目的是阐明 谷胱甘肽过氧化物酶活性部位的硒。

It is proposed to study the biological chemistry of sulfur in the thiol and disulfide forms and selenium in the selenol and diselenide forms. The long-term objectives of this research are to characterize chemical reactions which are central to the biological chemistry of sulfur and selenium, but which have not been quantitatively characterized because of a lack of experimental methods. Reactions will be characterized at the molecular level in intact erythrocytes, plasma and aqueous solution by NMR spectroscopy. Also, sensitive and selective methods based on high performance liquid chromatography (HPLC) with electrochemical detection will be developed and used to study the biological chemistry of thiols and disulfides in plasma and erythrocytes. The research on thiols and disulfides in intact erythrocytes will be designed to characterize intracellular thiol/disulfide chemistry under conditions of oxidative stress. Erythrocytes in vivo are regularly subjected to oxidative stress and conditions of oxidative stress exist in a diverse range of disease states. The proposed research will use noninvasive 1H-NMR methods to characterize the dynamics of intracellular thiol/disulfide chemistry of endogenous thiols and of thiol-containing drug molecules in erythrocytes as they are subjected to oxidative stress and as their intracellular region returns to its more normal reducing condition. HPLC methods will be used to determine disulfides formed at trace levels under these conditions, including hemoglobin-small molecule mixed disulfides. The chemistry of selenols and diselenides in intact erythrocytes will be studied by these same techniques with the objective of characterizing the intracellular chemistry of selenium in these forms. New and fundamental information about the oxidation-reduction chemistry of sulfur in amino acids, peptides, proteins and drug molecules will be obtained from studies of the kinetics and equilibria of thiol/disulfide exchange reactions in aqueous solution. The research will include studies of protein-small molecule mixed disulfides, which are through to be involved in processes as diverse as homocystinuria and drug-induced hypersensitivity, and studies of the disulfide groups in peptide hormones such as vasopressin and oxytocin. The kinetics and equilibria of reactions of thiols with diselenides and selenenylsulfides will also be characterized, with the objective of elucidating the chemistry of selenium at the active site of glutathione peroxidase.