Conformational changes in the myosin subfragment-2. Effect of pH on synthetic rod filaments.
Conformational changes in the myosin subfragment-2. Effect of pH on synthetic rod filaments.
复制标题
肌球蛋白亚片段 2 的构象变化。
DOI：
10.1016/0022-2836(82)90504-6
复制
发表时间：
1982
影响因子：
5.6
通讯作者：
Liu,J
中科院分区：
文献类型：
--
作者：
Reisler,E;Liu,J
化学交联和糜蛋白酶消化的合成杆丝进行，以检查亚片段-2（S-2）元素的构象特性。在这些实验中，仿照K. Sutoh，YC Chiao和WF哈灵顿的研究表明，S-2和轻酶解肌球蛋白（LMM）的交联速率在pH 7.0至8.3的范围内。在此pH范围内，S-2交联的标准化速率k s− 2 k LMM急剧下降，这与先前对肌球蛋白丝、肌原纤维和甘油化纤维的观察结果类似。在相同的pH范围内，杆丝的蛋白水解敏感性大大增加，模仿在肌球蛋白丝中观察到的类似增加。这些结果表明，肌球蛋白的S-2区域很容易受到电荷平衡的微小变化的影响，并表明在这部分分子的构象变化可能会导致肌球蛋白头部的处置的变化。
Chemical cross-linking and chymotryptic digestions of synthetic rod filaments were carried out in order to examine the conformational properties of the subfragment-2 (S-2) element. In these experiments, molded after those of K. Sutoh, YC Chiao and WF Harrington, the rates of S-2 and light meromyosin (LMM) cross-linking were followed over the pH range from 7.0 to 8.3. The normalized rate of S-2 crosslinking, k s− 2 k LMM, decreased sharply in this pH range, in analogy with previous observations on myosin filaments, myofibrils, and glycerinated fibers. The proteolytic susceptibility of rod filaments greatly increased over the same pH range, mimicking a similar increase that has been observed in myosin filaments. These results demonstrate that the S-2 region of myosin is readily affected by small changes in charge balance and suggest that conformational changes in this part of the molecule may lead to changes in the disposition of myosin heads.