PURCHASE OF A HIGH FIELD NMR SPECTROMETER

请拨资金购买一台高场核磁共振波谱仪 ~1H和~(13)C原子核的观测以确定复杂Low的结构 分子量化合物(相对分子质量小于6,000)和表征蛋白质 配基相互作用。建议进行研究，以确定 碳水化合物侧链的结构之间可能的关系 人纤维蛋白原链及其在人血浆中的浓度 有正常的和遗传的异常纤维蛋白原。核磁共振也将被使用 从细胞表面获得糖肽的结构测定 蛋白质，以及测定实验室合成的结构 辅因子、辅因子类似物、寡糖和底物 酶催化的反应。将尝试确定 咪唑等基团在多肽和蛋白质中的电离行为 通过测量~1H和~(13)C共振的pH依赖关系。其中一些 这些研究针对的是硫代咪唑的表征。 离子对相互作用似乎对活性很重要 几种蛋白质。此外，该仪器将用于确定 碳水化合物结合的热力学和动力学参数 凝集素。核泛滥效应与核泛滥的转移 将对影响进行研究，试图表征配体的变化。 它们与蛋白质结合的构象，FAD的相对配置 和NAD+，在硫酰胺脱氢酶和谷胱甘肽还原酶中，以及 确定酶结合底物类似物的取向 D-丝氨酸脱水酶中的磷酸吡哆醛。也将进行尝试 稳定的酶结合辅因子的结构测定 中间体，以努力建立叶酸的反应途径， 磷酸吡哆醛和黄素需求酶。此外， 将使用光谱仪来确定产品的结构和 监控酶催化反应的进展情况，如有其他方法 分析的结果是不可行的。

Funds are requested for purchase of a high field NMR spectrometer for observation of 1H and 13C nuclei to determine structures of complex low molecular weight compounds (Mr Less than 6,000) and to characterize protein ligand interactions. Studies are proposed directed toward determination of the possible relationship between the structure of the carbohydrate side chains of human fibrinogen and its concentration in plasma in individuals with normal and inherited abnormal fibrinogens. The NMR will also be used to determine the structure of glycopeptides obtained from cell surface proteins, as well as to determine the structure of laboratory synthesized cofactors, cofactor analogs, oligosaccharides, and substrates of enzymically catalyzed reactions. Attempts will be made to determine the ionization behavior of imidazole and other groups in peptides and proteins from measurements of the pH dependence of 1H and 13C resonances. Some of these studies are directed toward characterization of imidazolium thiolate ion pair interactions which appear to be important for the activity of several proteins. Additionally the instrument will be used to determine thermodynamic and kinetic parameters for the binding of carbohydrates to lectins. Nuclear Overhauser effects and transfer of nuclear Overhauser effects will be studied in attempts to characterize alterations in ligand conformation upon their binding to protein, the relative disposition of FAD and NAD+, in lipoamide dehydrogenase and glutathione reductase, as well as to determine the orientation of enzyme bound substrate analogs with respect to pyridoxal phosphate in D-serine dehydratase. Attempts also will be made to determine the structure of stabilized enzyme bound cofactor intermediates in an effort to establish reaction pathways for folate, pyridoxal phosphate and flavin requi0ing enzymes. Additionally the spectrometer will be used to determine the structure of products and monitor the progress of enzymically catalyzed reactions where other methods of analysis are not feasible.