Prostatic Binding Protein
Prostatic Binding Protein
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前列腺结合蛋白
DOI：
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发表时间：
1977
期刊：
影响因子：
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通讯作者：
P. Moor
中科院分区：
文献类型：
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作者：
W. Heyns;P. Moor
大鼠前列腺胞液中含有高浓度的前列腺结合蛋白，具有特殊的类固醇结合特性。事实上，尽管亲和力相对较低，但活性炭吸附可用于其测量。此外，这种结合对特定的类固醇没有特异性，并且在脱脂后非常强烈地增加。在去脂的胞质溶胶中，结合位点的浓度为3.1 μ mol/g蛋白质，对双烯醇酮的表观亲和力为1.7 × 106 M−1。前列腺液中高浓度的前列腺结合蛋白表明该物质由前列腺分泌。
前列腺结合蛋白具有以下物理化学特征：它在50 - 70%饱和度之间通过硫酸铵沉淀;从Sephadex G-100柱的洗脱位置对应于51000的分子量;它在3.7 S下在蔗糖密度梯度中沉淀，并在约0.25 M KCl下从DEAE-纤维素柱洗脱。在聚丙烯酰胺凝胶电泳上，结合活性与主要的胞浆蛋白带一致。该条带在7%凝胶中具有与血清白蛋白相同的迁移率，但在更浓缩的凝胶中具有更高的迁移率。
Rat prostatic cytosol contains a high concentration of a prostatic binding protein with peculiar steroid-binding properties. Indeed, in spite of a relatively low affinity, charcoal adsorption can be used for its measurement. Furthermore, the binding is not specific for particular steroids and increases very strongly after delipidation. In delipidated cytosol the concentration of the binding site is 3.1 μ mol/g protein and the apparent affinity for pregnenolone 1.7 × 106 M−1. The high concentration of prostatic binding protein in prostatic fluid shows that this substance is secreted by the prostate.
Prostatic binding protein has the following physicochemical characteristics: it is precipitated by ammonium sulfate between 50 and 70% saturation; the elution position from a Sephadex G-100 column corresponds to a molecular weight of 51000; it sediments in sucrose density gradients at 3.7 S and is eluted from DEAE-cellulose columns at about 0.25 M KCl. On polyacrylamide gel electrophoresis the binding activity coincides with the major cytosolic protein band. This band has the same mobility as serum albumin in 7% gels, but a higher mobility in more concentrated gels.