CYTOCHROME-P-450 ROTAMERS CONTROL MIXED-FUNCTION OXYGENATION IN RECONSTITUTED MEMBRANES - ROTATIONAL DIFFUSION STUDIED BY DELAYED FLUORESCENCE DEPOLARIZATION
CYTOCHROME-P-450 ROTAMERS CONTROL MIXED-FUNCTION OXYGENATION IN RECONSTITUTED MEMBRANES - ROTATIONAL DIFFUSION STUDIED BY DELAYED FLUORESCENCE DEPOLARIZATION
复制标题
DOI：
10.3109/00498258209038946
复制
发表时间：
1982-01-01
期刊：
影响因子：
1.8
通讯作者：
STIER, A
中科院分区：
文献类型：
--
作者：
GREINERT, R;FINCH, SAE;STIER, A
通过测量延迟荧光的时间依赖性偏振发射来研究纯化的兔肝微粒体细胞色素 P-450 LM2 在重构的脂质囊泡膜中的旋转扩散。用二碘荧光素碘乙酰胺标记的细胞色素 P-450 表现出绕膜法线的严格单轴旋转。苯丙胺延迟旋转，而细胞色素 P-450 底物复合物的还原则加速旋转。提出了一种模型，其中细胞色素 P-450 形成盘状旋转异构体，浸入双层膜中的深度随底物诱导和氧化还原状态依赖性构象变化而变化。该模型描述了电子转移控制混合功能氧化的调节机制。
Rotational diffusion of purified rabbit-liver microsomal cytochrome P-450 LM2 in reconstituted lipid-vesicle membranes was investigated by measurement of time-dependent polarized emission of delayed fluorescence. Cytochrome P-450 labeled with diiodofluorescein iodoacetamide exhibited strict uniaxial rotation about the normal to the membrane. Benzphetamine retards rotation, while reduction of the cytochrome P-450 substrate-complex accelerates rotation. A model is proposed in which cytochrome P-450 forms disc-shaped rotamers immersed in the bilayer membrane to a depth which is varied by substrate-induced and redox state-dependent conformational changes. The model describes a regulating mechanism of the electron transfer-controlling mixed-function oxygenation.