Proton-NMR studies of the solution conformations of vitamin-D-induced bovine intestinal calcium-binding protein.
Proton-NMR studies of the solution conformations of vitamin-D-induced bovine intestinal calcium-binding protein.
复制标题
维生素 D 诱导的牛肠钙结合蛋白溶液构象的质子核磁共振研究。
DOI：
10.1111/j.1432-1033.1983.tb07857.x
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发表时间：
1983
期刊：
影响因子：
--
通讯作者：
R. Wasserman
中科院分区：
文献类型：
--
作者：
D. Dalgarno;B. Levine;R. J. Williams;C. Fullmer;R. Wasserman
利用1H NMR研究了维生素d诱导的牛肠钙结合蛋白的溶液结构。最近发表的晶体结构有助于对天然蛋白质的研究；结果表明，该分子在晶体中的构象与在溶液中的构象非常相似。叙述了pH和温度对天然结构的影响。然后描述载脂蛋白的结构，并概述了pH和温度对其折叠的影响。载脂蛋白与天然蛋白折叠的比较表明，它们的折叠非常相似。这两个褶皱是通过钙滴定法联系起来的，这表明蛋白质按顺序结合了两个钙离子。Ca2+滴定的两个步骤都发生在缓慢交换（kex 80 s-1）的条件下。结合Ca2+离子的作用是引起螺旋的扭曲运动，螺旋作为杆，传递Ca2+结合引起的构象变化到蛋白质的连接区域。
1H NMR is used to study the solution structure of vitamin-D-induced bovine intestinal calcium-binding protein. The study of the native protein is aided by the recently published crystal structure; it is shown that the conformations of the molecule in the crystal and in solution are very similar. The effect of pH and temperature on the native structure is described. The structure of the apo protein is then described, and the effect of pH and temperature on its fold is outlined. A comparison between apo and native protein folds is made which indicates that the folds are very similar. The two folds are related by a calcium titration, which indicates that the protein binds two calcium ions sequentially. Both steps in the Ca2+ titration occur under conditions of slow exchange (kex 80 s-1). The effect of binding Ca2+ ions is to cause twisting motions of helices, with the helices acting as rods, relaying the conformational change induced by Ca2+ binding to the linker regions of the protein.