KINETIC-STUDIES ON REDUCTION OF CYTOCHROME-P-450 AND CYTOCHROME-B5 BY DITHIONITE
KINETIC-STUDIES ON REDUCTION OF CYTOCHROME-P-450 AND CYTOCHROME-B5 BY DITHIONITE
复制标题
DOI：
10.1111/j.1432-1033.1985.tb09001.x
复制
发表时间：
1985-01-01
期刊：
影响因子：
--
通讯作者：
ARCHAKOV, AI
中科院分区：
文献类型：
--
作者：
DAVYDOV, DR;KARYAKIN, AV;ARCHAKOV, AI
用停流技术研究了二亚硫酸盐还原细胞色素P-450[兔、大鼠]和b5的动力学。在所研究的所有情况下，细胞色素b5的还原动力学曲线均符合细胞色素的一级动力学，在10.6 mM二亚硫酸盐下的还原速率常数约为14 S~(-1)。细胞色素P-450的还原动力学曲线符合2个指数之和的方程，其参数随体系的不同而变化。在非离子洗涤剂Triton N-101存在下，细胞色素P-450的还原符合简单的一级动力学。二亚硫酸盐还原细胞色素P-450的表观双相性可能是由于血红蛋白不对称分布在微粒体膜和脂蛋白体膜以及溶液中的细胞色素低聚体中的结果。
The kinetics of reduction of cytochromes P-450 [rabbit, rat] and b5 by dithionite were studied in solution and in microsomal and proteoliposomal membranes by the stopped-flow technique. In all the cases studied the kinetic curves of reduction of cytochrome b5 obey 1st-order kinetics in relation to cytochrome with the rate constant about 14 s-1 at 10.6 mM dithionite. The kinetic curves of reduction of cytochrome P-450 fit an equation for the sum of 2 exponentials with the parameters varying from system to system. The simple 1st-order kinetics of cytochrome P-450 reduction were observed in the presence of non-ionic detergent Triton N-101. The apparent biphasity of cytochrome P-450 reduction by dithionite should be the result of asymmetric distribution of hemoprotein in microsomal and proteoliposomal membranes as well as in cytochrome oligomers in solution.