Inagami T, Okamoto H, Ohtsuki K, Shimamoto K, Chao J, Margolius H S
J Clin Endocrinol Metab. 1982 Oct;55(4):619-27. doi: 10.1210/jcem-55-4-619.
A new affinity chromatographic procedure was devised to purify inactive renin by using a selective hydrophobic interaction of inactive renin to octyl-Sepharose. Additional extensive purification was accomplished by immunoaffinity chromatography on antihuman renin immunoglobulin G-Sepharose. A trace amount of active renin was removed by chromatography on pepstatin-Sepharose. Human plasma inactive renin purified by this method was free from protease inhibitors and permitted the investigation of protease-mediated activation without the acid treatment which was used previously to remove inhibitors. Human plasma kallikrein, human plasmin, cathepsin B1, and arginine esteropeptidases associated with mouse epidermis growth factor and nerve growth factor were effective activators. Human urinary kallikrein, hog pancreatic kallikrein, and rat urinary esterase A were inefficient activators of low potency. Thrombin, factor Xa, factor XIIa, and urokinase did not activate inactive renin. The in vitro activation of 56,000-dalton inactive renin by these proteases was not accompanied by a recognizable reduction in molecular weight. Activation required plasma albumin, presumably as a protecting substance. These results suggest that human inactive renin can be activated by a minimum change in its molecular size.
设计了一种新的亲和色谱方法，利用无活性肾素与辛基琼脂糖的选择性疏水相互作用来纯化无活性肾素。通过在抗人肾素免疫球蛋白G-琼脂糖上进行免疫亲和色谱完成了进一步的广泛纯化。通过在胃蛋白酶抑制剂-琼脂糖上进行色谱法去除了微量的活性肾素。用这种方法纯化的人血浆无活性肾素不含蛋白酶抑制剂，并且可以在不进行先前用于去除抑制剂的酸处理的情况下研究蛋白酶介导的激活。人血浆激肽释放酶、人纤溶酶、组织蛋白酶B1以及与小鼠表皮生长因子和神经生长因子相关的精氨酸酯肽酶是有效的激活剂。人尿激肽释放酶、猪胰激肽释放酶和大鼠尿酯酶A是低效的低效能激活剂。凝血酶、因子Xa、因子XIIa和尿激酶不激活无活性肾素。这些蛋白酶对56,000道尔顿无活性肾素的体外激活并没有伴随着分子量的明显降低。激活需要血浆白蛋白，推测其作为一种保护物质。这些结果表明，人无活性肾素可以通过其分子大小的最小变化而被激活。
