PROPERTIES OF GLUTATHIONE-PEROXIDASE ISOLATED FROM HUMAN-PLASMA
PROPERTIES OF GLUTATHIONE-PEROXIDASE ISOLATED FROM HUMAN-PLASMA
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DOI：
10.1016/0162-0134(87)80073-9
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发表时间：
1987-08-01
影响因子：
3.9
通讯作者：
WHANGER, PD
中科院分区：
文献类型：
--
作者：
BRODERICK, DJ;DEAGEN, JT;WHANGER, PD
人血浆谷胱甘肽过氧化物酶（GPx）经硫酸铵分级分离、SephadexG-150凝胶过滤、DEAESephacel层析、聚缓冲液聚焦层析和SephadexG-75凝胶过滤纯化。这种分离导致酶纯化约5，400倍，酶活性产率为32%。最终制剂的比活性为每毫克蛋白质约28单位（氧化NADPH纳摩尔）。对纯化的酶进行硒的测定揭示了每摩尔GPx 3.8克原子的含量。使用SDS与标准蛋白质的凝胶电泳显示亚基的分子量约为23，000，这表明天然酶的分子量约为92，000。纯化的GPx的氨基酸分析表明天冬氨酸、谷氨酸、脯氨酸、甘氨酸、丙氨酸和亮氨酸为主要氨基酸，半胱氨酸、甲硫氨酸、色氨酸和组氨酸为次要氨基酸。
Human plasma glutathione peroxidase (GPx) was purified to homogeneity by ammonium sulfate fractionation, gel filtration on Sephadex G-150, chromatography on DEAE Sephacel, chromatofocusing with polybuffer, and gel filtration with Sephadex G-75. This isolation resulted in about 5,400-fold purification of the enzyme with a 32% yield on enzyme activity. The final preparation had a specific activity of about 28 units (nmoles NADPH oxidized) per milligram of protein. Determination of selenium on the purified enzyme revealed a content of 3.8 g atoms per mole GPx. Gel electrophoresis using SDS with standard proteins revealed a molecular weight of about 23,000 for the subunits, which would indicate a molecular weight of about 92,000 for the native enzyme. Amino acid analyses of the purified GPx indicated aspartate, glutamate, proline, glycine, alanine, and leucine as the predominant amino acids and cysteine, methionine, tryptophan, and histidine as the minor amino acids.