Purification and characterization of a glutathione dependent dehydroascorbate reductase from human erythrocytes.
Purification and characterization of a glutathione dependent dehydroascorbate reductase from human erythrocytes.
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从人红细胞中纯化和表征谷胱甘肽依赖性脱氢抗坏血酸还原酶。
DOI：
10.1006/bbrc.1996.0555
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发表时间：
1996
期刊：
影响因子：
--
通讯作者：
Wells,WW
中科院分区：
文献类型：
--
作者：
Xu,DP;Washburn,MP;Sun,GP;Wells,WW
从人红细胞中纯化GSH依赖性脱氢抗坏血酸还原酶（EC 1.8.5.1）至均一。该酶是32 kDa的单体，并从粗DEAE-Sepharose级分纯化133倍，产率为25%。经等电聚焦判断，还原蛋白质的pI为5.1。动力学分析得出kcat为316 min−1，DHA的Km为0.21 mM，kcat/Km为2.47 × 104 M − 1 sec −1，GSH的Km为3.5 mM，kcat/Km为1.51 × 103 M − 1 sec −1。这是从人红细胞中分离的第二种DHA还原酶（在巯基转移酶之后），但与巯基转移酶不同，它没有巯基-二硫化物氧化还原酶活性。
A GSH-dependent dehydroascorbate reductase (EC 1.8.5.1) was purified to homogeneity from human erythrocytes. The enzyme was a monomer of 32 kDa and was purified 133-fold from a crude DEAE-Sepharose fraction with a 25% yield. The reduced protein had a pI of 5.1 as judged by isoelectric focusing. Kinetic analysis gave a kcatof 316 min−1, a Kmof 0.21 mM for DHA with a kcat/Kmof 2.47 × 104M−1sec−1, and a Kmof 3.5 mM for GSH with a kcat/Kmof 1.51 × 103M−1sec−1. This is the second DHA reductase (after thioltransferase) isolated from human erythrocytes, but unlike thioltransferase, it has no thiol-disulfide oxidoreductase activity.