牛肉肾上腺皮质中3-羟基-3-甲基戊二酰辅酶A还原酶的活性

3-Hydroxy-3-methylglutaryl coenzyme A reductase activity in beef adrenal cortex.

作者信息

Preiss B, Tan L, Lehoux J G

出版信息

Can J Biochem. 1978 Oct;56(10):958-62. doi: 10.1139/o78-149.

PMID:31970

Abstract

3-Hydroxy-3-methylglutaryl coenzyme A reductase (HMG-CoA reductase) activity (mevalonate:NADP+ oxidoreductase )CoA-acylating) EC 1.1.1.34) was demonstrated in beef adrenal cortex. Most of the HMG-CoA reductase activity is in the microsomal fraction while a small percentage of the activity is associated with the mitochondria, Mitochondria purified on a linear sucrose gradient are enriched in HMG-CoA reductase and cytochrome c oxidase activities. The reductase present in microsomal preparations from the whole adrenal cortex has an apparent Km of 5.6 X 10(-5) M for (R,S)-HMG-CoA. Reductase activities found in the microsomal fractions from the zona glomerulosa, the zona fasciculata, and the zona reticularis were 1.32, 7.37, and 9.74 nmol mevalonate formed per milligram protein in 30 min respectively.

摘要

在牛肾上腺皮质中证实了3-羟基-3-甲基戊二酰辅酶A还原酶（HMG-CoA还原酶）活性（甲羟戊酸：NADP⁺氧化还原酶，辅酶A酰化）（EC 1.1.1.34）。大部分HMG-CoA还原酶活性存在于微粒体部分，而一小部分活性与线粒体相关。在线性蔗糖梯度上纯化的线粒体富含HMG-CoA还原酶和细胞色素c氧化酶活性。来自整个肾上腺皮质的微粒体制剂中存在的还原酶对（R,S）-HMG-CoA的表观Km为5.6×10⁻⁵M。在球状带、束状带和网状带的微粒体部分中发现的还原酶活性分别为每毫克蛋白质在30分钟内形成1.32、7.37和9.74 nmol甲羟戊酸。