Parsons R G, Hoch J A
Eur J Biochem. 1976 Dec;71(1):1-8. doi: 10.1111/j.1432-1033.1976.tb11082.x.
A malignancy-associated human serum DNA-binding protein (C3DP protein), which was previously detected using dodecylsulfate gel electrophoresis, has been purified and characterized. This protein was isolated from human fetal cord serum by DNA-cellulose affinity chromatography, ammonium sulfate fractionations, DEAE-cellulose chromatography, and Sephadex gel filtration. The molecular weight of purified C3DP protein has been shown to be 135000 by ultracentrifugation, gel filtration, and dodecylsulfate gel electrophoresis. Dodecylsulfate gel electrophoresis following disulfide bond reduction has revealed that this protein is composed of three subunits having molecular weights of 74000, 40000 and 22000. Carbohydrate has been demonstrated to be attached to the 74000 and 22000 molecular weight components. Immunochemical studies have revealed that the C3DP protein is a fragment of human complement component C3, which closely resembles C3c.
一种先前通过十二烷基硫酸盐凝胶电泳检测到的与恶性肿瘤相关的人血清DNA结合蛋白（C3DP蛋白）已被纯化和鉴定。该蛋白通过DNA-纤维素亲和色谱、硫酸铵分级分离、DEAE-纤维素色谱和Sephadex凝胶过滤从人胎儿脐带血清中分离出来。通过超速离心、凝胶过滤和十二烷基硫酸盐凝胶电泳显示，纯化的C3DP蛋白的分子量为135000。二硫键还原后的十二烷基硫酸盐凝胶电泳表明，该蛋白由三个分子量分别为74000、40000和22000的亚基组成。已证明碳水化合物与分子量为74000和22000的组分相连。免疫化学研究表明，C3DP蛋白是人类补体成分C3的一个片段，与C3c非常相似。
