胆固醇侧链裂解的机制。II. 在富含18O的水中，差向异构的20-氢过氧胆固醇的酶促氢过氧化物-二醇重排反应
Mechanism of cholesterol side-chain cleavage. II. The enzymic hydroperoxide-glycol rearrangement of the epimeric 20-hydroperxycholesterols in 18O-enriched water.
作者信息
Van Lier J E, Rousseau J, Langlois R, Fisher G J
出版信息
Biochim Biophys Acta. 1977 May 25;487(2):395-9. doi: 10.1016/0005-2760(77)90016-9.
Incubation of 20 alpha-hydroperoxycholesterol (I) and its 20 beta-isomer, 20 beta-hydroperoxy-20 isocholesterol (II) with adrenocortical mitochondrial preparations in the absence of molecular oxygen, in normal and 18O-enriched water, gave 20 alpha, 22R-dihydroxycholesterol (III) from I and 20 beta,21-dihydroxy-20-iso-cholesterol (IV) from II. Mass spectral analysis of the persilylated glycol products III and IV showed no uptake of 18O, indicating that the oxygen atoms of the C20-, C22- and C21-hydroxyl groups originated from the 20-hydroperoxy atomic oxygen complex is the intermediate in the enzymic oxidative reactions of cholesterol side-chain cleavage.
在不存在分子氧的情况下，将20α-氢过氧化胆固醇（I）及其20β-异构体20β-氢过氧化-20-异胆固醇（II）与肾上腺皮质线粒体制剂在正常水和富含18O的水中温育，I生成了20α,22R-二羟基胆固醇（III），II生成了20β,21-二羟基-20-异胆固醇（IV）。对经全硅烷化处理的二醇产物III和IV进行质谱分析，结果显示没有摄取18O，这表明C20-、C22-和C21-羟基的氧原子源自20-氢过氧化原子氧复合物，该复合物是胆固醇侧链裂解酶促氧化反应中的中间体。
Zotero 插件