The low-molecular-weight (40 000) form of renin was converted into the high-molecular-weight (60 000) form of renin with sulphydryl oxidation, and the high-molecular-weight form of renin was re-converted into the low-molecular-weight form with a reduction of disulphide bonds in the renal cortical homogenate of the dog. Therefore, the low- and high-molecular-weight forms of renin were interconvertible. 2. The formation of high-molecular-weight form of renin required a renin binding substance which was found to be included in the cytosol fraction of kidney cortex of the dog. 3. The renin binding substance of the dog was unstable to heat and low pH, but vitally resistant to Triton X-100 and chloroform. It did not bind to concanavalin A Sepharose 4B. 4. The renin binding substance was eluted in the molecular-weight region between 156 000 and 60 000 on Sephadex G-200, and such apparent molecular weight was not altered by urea at 4 mol/l; thus molecular weight greater than the theoretically expected value of 20 000 was indicated.
摘要
低分子量（40000）形式的肾素通过巯基氧化转化为高分子量（60000）形式的肾素，而在犬肾皮质匀浆中，高分子量形式的肾素通过二硫键还原又重新转化为低分子量形式。因此，肾素的低分子量和高分子量形式是可以相互转换的。2. 高分子量形式肾素的形成需要一种肾素结合物质，该物质被发现存在于犬肾皮质的胞质溶胶部分。3. 犬的肾素结合物质对热和低pH不稳定，但对Triton X - 100和氯仿具有抗性。它不与伴刀豆球蛋白A琼脂糖4B结合。4. 肾素结合物质在Sephadex G - 200上于分子量156000至60000区域被洗脱，且这种表观分子量在4mol/l尿素存在时不变；因此表明其分子量大于理论预期值20000。
