Proteolysis and the domain organization of myosin subfragment 1.
Proteolysis and the domain organization of myosin subfragment 1.
复制标题
肌球蛋白亚片段 1 的蛋白水解和结构域组织。
DOI：
10.1073/pnas.81.3.736
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发表时间：
1984
影响因子：
11.1
通讯作者：
Morales,MF
中科院分区：
文献类型：
--
作者：
Mornet,D;Ue,K;Morales,MF
由于折叠多肽的蛋白水解切割不仅取决于蛋白酶的特异性，而且取决于折叠的性质，我们研究了七种具有不同特异性的蛋白酶对（胰凝乳蛋白酶产生的）亚片段1（命名为“S-1”）或肌球蛋白“头部”片段的切割。所有7个产生了大致相同的S-1的三个片段，即27、50和20千道尔顿的片段（来自NH 2末端），这表明在完整的S-1中，这些片段是不同的结构域。使用相同的蛋白酶水解S-1的MgADP复合物。除胰蛋白酶外，所有人都未能做到这一点，如早先发现的[Hozumi，T.（1983）Biochemistry 22，799-804]，产生两个另外的裂解。这一结果表明，MgADP诱导的构象变化只打开了一小段多肽链，这段多肽链恰好易受胰蛋白酶的攻击。
Because the proteolytic cleavage of a folded polypeptide depends not only on the specificity of the protease but on the nature of the folding, we investigated the cleavage of (chymotryptically produced) subfragment 1 (designated "S-1") or "head" segment of myosin by seven proteases with different specificities. All seven produced approximately the same three fragments of S-1--namely, fragments (from the NH2 terminus) of 27, 50, and 20 kilodaltons, suggesting that in intact S-1 these fragments are distinct domains. The same proteases were used to hydrolyze the MgADP complex of S-1. All failed to do so except trypsin, which, as found earlier [Hozumi, T. (1983) Biochemistry 22, 799-804], makes two additional cleavages. This result suggests that the conformational change induced by MgADP opens up only a small stretch of polypeptide chain, which stretch happens to be vulnerable to trypsin.