Conformational change in thrombospondin induced by removal of bound Ca2+. A spin label approach.
Conformational change in thrombospondin induced by removal of bound Ca2+. A spin label approach.
复制标题
去除结合的 Ca2 引起血小板反应蛋白的构象变化。
DOI：
10.1016/0014-5793(88)81157-8
复制
发表时间：
1988
期刊：
影响因子：
3.5
通讯作者：
Lai,CS
中科院分区：
文献类型：
--
作者：
Slane,JM;Mosher,DF;Lai,CS
用ESR自旋标记技术研究了去除与凝血酶敏感蛋白(TSP)结合的钙离子对溶液中蛋白质结构的影响。马来酰亚胺自旋标记选择性地附着在游离的硫醇基团上，推测靠近钙结合部位所在的羧基末端区域。自旋标记TSP的ESR谱表明，结合标记经历了较快的旋转运动，在纳秒范围内具有有效的旋转关联时间。通过将自旋标记的TSP从含钙的缓冲液中透析到含EDTA的缓冲液中来去除TSP中的结合钙，导致结合标记的迁移率增加了2.3倍。这些数据表明，EDTA与TSP中结合的钙离子的络合至少在自旋标记位置附近引起了TSP的构象变化。
The effect of removal of Ca2+bound to thrombospondin (TSP) on the protein structure in solution has been investigated using ESR spin-label techniques. A maleimide spin label was selectively attached to the free thiol group presumably near the carboxyl-terminal domain in which Ca2+-binding sites are situated. The ESR spectra of spin-labeled TSP showed that the bound label undergoes a relatively fast rotational motion with an effective rotational correlation time in the nanosecond time regimes. Removal of bound Ca2+in TSP by dialyzing spin-labeled TSP from a Ca2+-containing buffer into an EDTA-containing buffer resulted in an increase in the mobility of the bound label by a factor of 2.3. The data suggest that EDTA chelation of bound Ca2+in TSP induces a conformational change of TSP at least near the site of spin labeling.