Dean R T
Eur J Biochem. 1975 Oct 1;58(1):9-14. doi: 10.1111/j.1432-1033.1975.tb02342.x.
The degradation of cytosol proteins in vitro by purified cathepsin D and cathepsin B1 and by mixtures of lysosomal enzymes, was studied. By means of a double-labelling method, it was shown that the relative rates of degradation of cytosol proteins by the purified enzymes and by mixtures of enzymes under a wide range of conditions in vitro correlated well with their relative rates of turnover in vivo. The complex mixture of cytosol proteins was degraded less rapidly after denaturation than in the native state, both by the purified proteases and by the mixture of lysosomal enzymes. This contrasts with previous results on proteolysis of single purified proteins. The possible role of lysosomal enzymes in turnover in vivo was discussed.
研究了纯化的组织蛋白酶D和组织蛋白酶B1以及溶酶体酶混合物在体外对胞质溶胶蛋白的降解作用。通过双标记法表明，在体外广泛条件下，纯化酶和酶混合物对胞质溶胶蛋白的相对降解速率与其在体内的相对周转速率密切相关。无论是纯化的蛋白酶还是溶酶体酶混合物，变性后的胞质溶胶蛋白复杂混合物的降解速度都比天然状态下慢。这与先前关于单一纯化蛋白蛋白水解的结果形成对比。讨论了溶酶体酶在体内周转中的可能作用。
