Usanov S A, Turko I V, Chashchin V L, Akhrem A A
Bioorg Khim. 1984 Nov;10(11):1457-68.
The molecular organization of adrenocortical cytochrome P-450scc has been investigated using chemical modification with bifunctional imidates. The oligomeric organization of cytochrome P-450scc in solution has been shown. The application of dimethyl-3,3'-dithiobispropioimidate and subsequent cleavage of the modified products by reducing agents revealed the presence of two types of intramolecular cross-links: "short" at the distance of 3,0 A between the amino groups of lysine residues and "long" ones at a distance of 11,9 A. The analysis of the products, obtained by limited proteolysis of the oligomeric forms of the cross-linked cytochrome P-450, by two-dimensional electrophoresis has shown that the cross-links are formed between the functional domain (fragment F1) and domain responsible for the interaction with the phospholipid membrane (fragment F2). A model for cytochrome P-450scc molecular organization has been suggested on the basis of the obtained results.
已使用双功能亚氨酸酯进行化学修饰来研究肾上腺皮质细胞色素P-450scc的分子组织。已证明细胞色素P-450scc在溶液中的寡聚组织。应用二甲基-3,3'-二硫代双丙亚氨酸酯并随后用还原剂裂解修饰产物，揭示了两种类型的分子内交联：赖氨酸残基氨基之间距离为3.0 Å的“短”交联和距离为11.9 Å的“长”交联。通过二维电泳对交联细胞色素P-450的寡聚形式进行有限蛋白酶解得到的产物分析表明，交联是在功能域（片段F1）和负责与磷脂膜相互作用的域（片段F2）之间形成的。基于所得结果提出了细胞色素P-450scc分子组织的模型。
