Studies on Cytochrome c Modified by [PtdienNO_3]Cl

For the first time, [PtdienNO_3]Cl was used as a stable reagent to modify ferricytochrome c and the reaction products were separated and purified with the CM-52 cation exchange chromatography. Five components were obtained, corresponding to the native cytochrome c single-labeled, dual-labeled, and triple-labeled derivatives as shown by the analysis of the molar ratio of the two metal atoms (Pt and Fe). The reduction potentials of these proteins were measured by differential pulse voltammetry. His-33 and Trp-59 were identified by~1HNMR as the binding sites of the platinum complex in the modified cytochrome c derivatives. Trp-59 was a conserved amino acid connected with the heme through hydrogen bond, which had not been modified by other transition metal complexes. The platinummodified cytochrome c derivatives might be valuable in exploring the role of the aromatic amino acids, especially Trp-59, in electron transfer.     

利用光的反射对弦振动实验的改进

为了解决弦振动实验在操作过程中拉力杆无法水平而导致实验误差偏大的问题,研究改进了弦振动装置,使实验误差得到了很大程度的降低。本文利用光的反射原理,很好地解决了传统弦振动实验用肉眼观察拉力杠杆水平带来的较大误差的问题。研究表明通过改进的实验装置探究共振频率和弦上波腹数的关系其相对误差平均降低了1.94%,很好地验证了改进方案的可行性和有效性。     

[PtdienNO_3]Cl与细胞色素c修饰体系研究

本实验首次以稳定修饰试剂[PtdienNO_3]Cl标记细胞色素c,反应产物经CM-52阳离子交换色谱分离纯化得细胞色素c单修饰、双修饰及三修饰衍生物。用微分脉冲伏安测定各修饰产物的还原电位,并以~1H NMR波谱证实[PtdienNO_3]Cl在细胞色素c上的修饰位点为His-33和Trp-59,其中Trp-59是其它过渡金属配合物所未能标记的、与血红素以氢键相连的保守氨基酸。细胞色素c Trp-59标记衍生物的获得,为研究芳香族氨基酸在细胞色素c电子转移过程中的作用提供了有价值的实验材料。