A Study of Electron-Transfer Pathways in the Electron-Transfer Reactions of Metal Complexes and Hemoproteins

金属配合物与血红素蛋白电子转移反应中电子转移途径的研究

基本信息

批准号：
03453049
负责人：
TSUKAHARA Keiichi
金额：
$ 4.42万
依托单位：
Nara Women's University
依托单位国家：
日本
项目类别：
Grant-in-Aid for General Scientific Research (B)
财政年份：
1991
资助国家：
日本
起止时间：
1991 至 1992
项目状态：
已结题

项目摘要

1) Role of the Heme Propionates in the Reduction of Metmyoglobin-It is suggested that the heme propionates have an important role in the reductions of metmyoglobins by using the dimethylester hemins and octaethylhemin which has no propionates in the heme.2) Redox Behavior of Viologen Attached Metmyoglobin-Metmyoglobin whose lysine residue was modified with viologen was newly prepared and reduced by dithionite ions faster than native metmyoglobin. It is suggested that the viologen attached to myoglobin is reduced, following the rapid intramolecular electron-transfer reaction from the viologen radical cation to the iron(III) center.3) Syntheses and Characterizations of a New Type of Viologen-Linked N-Alkylporphyrin and Its Zinc(II) Complex-New type of viologen-linked tetraphenylporphyrin and its zinc(II) complex containing an N-trimethylene bridge were synthesized and characterized by a two dimensional ^1H-NMR spectroscopy. The decay of the porphyrin-based fluorescence was fitted by two … More exponentials, suggesting the presence of two conformers with respect to the orientation of viologen.4) Photoinduced Electron-Transfer Reactions of Zinc and Magnesium Myoglobins-Both photoinduced electron-transfer and thermal backward electron-transfer reactions of zinc and magnesium myoglobins with cationic quenchers were bimolecular steps and the reaction rates were insensitive to the driving force of reactions, suggesting that the reactions are controlled by conformational changes of myoglobins. The intramolecular photoinduced electrontransfer was observed in a zinc myoglobin-hexacyanoferrate(III) complex, which forms by electrostatic interactions, and was inhibited in addition of poly-L-lysine by forming a stable complex of poly-L-lysine and hexacyanoferrate(III) ions.5) Syntheses and Characterizations of Optical Active Viologens-Optical acitive viologens (OAV^<2+>) were newly synthesized and characterized. The stereoselectivity was found for the formation of the charge-transfer complex of OAV^<2+> with an L-ascorbate ion and for the ion-pair formation between OAV^<2+> and poly-L-glutamate ion. Less

1) 血红素丙酸盐在高铁肌红蛋白还原中的作用-通过使用血红素中不含丙酸盐的二甲酯血红素和八乙基血红素，表明血红素丙酸盐在高铁肌红蛋白的还原中具有重要作用。2) 紫精的氧化还原行为新制备了附着的高铁肌红蛋白-其赖氨酸残基被紫精修饰的高铁肌红蛋白，并通过以下方法还原：连二亚硫酸根离子比天然高铁肌红蛋白更快，这表明在从紫精自由基阳离子到铁（III）中心的快速分子内电子转移反应之后，附着在肌红蛋白上的紫精被还原。3）新型二亚硫酸根的合成和表征。紫碱连接的N-烷基卟啉及其锌(II)络合物-新型紫碱连接的四苯基卟啉及其合成了含有 N-三亚甲基桥的锌 (II) 配合物，并通过二维 ^1H-NMR 光谱进行了表征。基于卟啉的荧光的衰减通过两个指数拟合，表明存在两个构象异构体。 4) 锌和镁肌红蛋白的光致电子转移反应-锌和镁的光致电子转移和热后向电子转移反应带有阳离子猝灭剂的肌红蛋白是双分子步骤，反应速率对反应驱动力不敏感，表明反应是由肌红蛋白的构象变化控制的，在肌红蛋白-六氰基铁(III)复合物中观察到分子内光诱导电子转移。它是通过静电相互作用形成的，并且通过形成聚-L-赖氨酸和聚-L-赖氨酸的稳定复合物而受到抑制。 5)光学活性紫精的合成与表征-新合成并表征了光学活性紫精(OAV^<2+>)，发现了OAV^<电荷转移配合物的形成具有立体选择性。 2+>与L-抗坏血酸离子以及OAV^<2+>和聚-L-谷氨酸离子之间的离子对形成。