吡啶、2-甲基吡啶存在下细胞色素c碱式异构化和配体细胞色素c配合物的电化学研究

用半胱氨酸修饰的金电极研究了吡啶、2 甲基吡啶存在下细胞色素c碱式异构化和配体结合细胞色素c的电化学。在此电极上 ,细胞色素c可发生准可逆的电极反应而吡啶结合细胞色素c和 2 甲基吡啶结合细胞色素c在循环伏安图上只给出还原峰。高浓度 (1.2 7mol·L- 1)的吡啶和 2 甲基吡啶可诱导碱式细胞色素c在中性条件下生成。进一步的研究表明 ,这种诱导作用与配体和细胞色素c的键合无关

Electrochemical Study on the Alkaline Isomerization of Cytochrome c and Ligand Binding Cytochrome c in the Presence of Pyridine and 2-methyl- pyridine

The alkaline isomerization of horse heart cytochrome c and ligand-binding cyt c in the presence of pyridine and 2-methyl-pyridine has been studied using cyclic voltammetry at a gold disc electrode modified with cysteine over a range of solution pH. At this modified electrode, cyt c shows a quasi-reversible electrode process while the cyclic voltammograms of alkaline cyt c and py· cyt c only give cathodic peaks. At neutral pH, high concentrations (1.27 mol·L^-1) of py and 2-mpy caused the formation of alkaline cyt c which appeared only when pH was above 9 in the absence of such ligands. These results confirm the conclusion of previous NMR studies that py and its derivatives induce the formation of the alkaline cyt c at neutral pH. Further investigation indicates that the inducement function is not involved in the ligand's coordination to the heme iron.