Guryev O L, Dubrovsky T B, Chernogolov A A, Dubrovskaya S B, Nicolini C, Usanov S A
Institute of Bioorganic Chemistry, Academy of Sciences of Belarus, Minsk, Belarus.
Biochemistry (Mosc). 1997 Jun;62(6):641-7.
Langmuir-Blodgett films prepared from cytochrome P450scc and its complex with adrenodoxin have been prepared and studied. Adrenodoxin was preliminarily selectively modified with fluorescein isothiocyanate and the effect of this modification on the interaction with cytochrome P450scc was studied. Using selectively modified adrenodoxin the ratio of the proteins in the film was found to be 1 mole of adrenodoxin per 2 moles of cytochrome P450scc. Langmuir-Blodgett films were also prepared from adrenodoxin-reductase and it was shown that this flavoprotein is transferred to the substrate as an apo-protein. It is also shown that the adrenodoxin-binding region of cytochrome P450scc is exposed to the subphase under all pressures in the interval studied. The relationship between the orientation of cytochrome P450scc-adrenodoxin complex in monolayers on the water-air interface and the pressure produced at the interface at the moment of monolayer formation was found. Our data are in excellent accordance with ideas on the molecular organization of cytochrome P450scc in the inner adrenocortical membrane and allows the use of this approach to model membrane structures containing cytochrome P450.
已制备并研究了由细胞色素P450scc及其与肾上腺铁氧还蛋白的复合物制成的朗缪尔-布洛杰特膜。肾上腺铁氧还蛋白先用异硫氰酸荧光素进行了选择性修饰，并研究了这种修饰对其与细胞色素P450scc相互作用的影响。使用选择性修饰的肾上腺铁氧还蛋白，发现膜中蛋白质的比例为每2摩尔细胞色素P450scc对应1摩尔肾上腺铁氧还蛋白。还制备了由肾上腺铁氧还蛋白还原酶制成的朗缪尔-布洛杰特膜，结果表明这种黄素蛋白作为脱辅基蛋白转移到底物上。研究还表明，在所研究的压力区间内，细胞色素P450scc的肾上腺铁氧还蛋白结合区域在所有压力下都暴露于亚相。发现了水-空气界面上单分子层中细胞色素P450scc - 肾上腺铁氧还蛋白复合物的取向与单分子层形成瞬间界面处产生的压力之间的关系。我们的数据与关于肾上腺皮质内膜中细胞色素P450scc分子组织的观点非常一致，并允许使用这种方法来模拟含有细胞色素P450的膜结构。
