THIOL-PROTEIN DISULFIDE OXIDOREDUCTASES - ASSAY OF MICROSOMAL MEMBRANE-BOUND GLUTATHIONE-INSULIN TRANSHYDROGENASE AND COMPARISON WITH PROTEIN DISULFIDE-ISOMERASE
THIOL-PROTEIN DISULFIDE OXIDOREDUCTASES - ASSAY OF MICROSOMAL MEMBRANE-BOUND GLUTATHIONE-INSULIN TRANSHYDROGENASE AND COMPARISON WITH PROTEIN DISULFIDE-ISOMERASE
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DOI：
10.1042/bj1590377
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发表时间：
1976-01-01
影响因子：
4.1
通讯作者：
FREEDMAN, RB
中科院分区：
文献类型：
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作者：
IBBETSON, AL;FREEDMAN, RB
CO对内源性微粒体NADP氧化酶的抑制使得膜结合谷胱甘肽-胰岛素转氢酶（EC 1.8.4.2）能够通过涉及NADPH和谷胱甘肽还原酶的联合测定法（EC 1.6.4.2）方便地进行测定。在大鼠肝微粒体制剂中酶的比活性为1 nmol氧化型谷胱甘肽形成/min/mg膜蛋白的数量级。酶的比活性在粗糙和光滑微粒体组分中相当，并且活性不受EDTA处理和从粗糙微粒体组分中去除核糖体的影响。膜结合型谷胱甘肽-胰岛素转氢酶不受浓度高达0.5%的脱氧胆酸盐的影响;蛋白质二硫化物异构酶（EC 5.3.4.1）被显著抑制。在大鼠肝微粒体组分中，谷胱甘肽-胰岛素转氢酶和蛋白二硫化物异构酶活性并不都由单一的酶物种催化。
Inhibition of endogenous microsomal NADP oxidase by CO enables membrane-bound glutathione-insulin transhydrogenase (EC 1.8.4.2) to be assayed conveniently by a linked assay involving NADPH and glutathione reductase (EC 1.6.4.2). The specific activity of the enzyme in rat liver microsomal preparations is of the order of 1 nmol of oxidized glutathione formed/min per mg of membrane protein. The specific activity of the enzyme is comparable in rough and smooth microsomal fractions, and the activity is not affected by treatment with EDTA and the removal of ribosomes from rough microsomal fractions. Membrane-bound glutathione-insulin transhydrogenase is not affected by concentrations of deoxycholate up to 0.5%; protein disulfide-isomerase (EC 5.3.4.1) is drastically inhibited. In rat liver microsomal fractions glutathione-insulin transhydrogenase and protein disulfide-isomerase ativities are not both catalyzed by a single enzyme species.