稀土发光探针研究植物钙调素及其与拮抗剂的相互作用

Studies on Plant Calmodulin and Its Interaction with Antagonist W7 by Ln3+ Luminescence Probes

从花椰菜（Ｂｒａｓｉｃａｏｌｅｒａｃｅａｖａｒ，ｂｏｔｒｙｔｉｓＬ．）中提取、纯化植物钙调素（ＣａＭ），并通过激活辅酶Ｉ激酶及Ｎ（６氮基）５氯萘磺胺（Ｗ７）拮抗实验对其进行鉴定。通过内源荧光及三价铽发光确定了花椰菜钙调素中含有一个酪氨酸（Ｔｙｒ）及４个金属结合位点，利用Ｆｒｓｔｅｒ型能量传递理论测量了Ｔｙｒ→Ⅲ，Ⅳ位点之间距离分别为１２３ｎｍ及１１８ｎｍ，进一步通过Ｅｕ３＋、Ｔｂ３＋发光的结果说明植物钙调素与拮抗剂Ｗ７结合过程中，钙调素的构象发生了变化，但其金属配位环境基本无变化。

lant calmodulin(CaM) has been purified from cauliflower and identified with NAD kinase(NADK) activation and inhibition effect of CaM antigonist W7. CaM′s intrinsic fluorescence and Tb3+ fluorescence showed that there was one tyrosine residue and four metalbinding sites in cauliflower CaM. Based on Fostertype nonradiative energy transfer theory, the distances of Tyr→sites Ⅲ, Ⅳ has been determined, and these are 123 nm(Tyr→site Ⅲ) and 118 nm(Tyr→site Ⅳ). The Eu3+ and Tb3+ fluorescence probes showed that the combination of CaM with W7 made a significant change on CaM′s conformation, but did not affect coordination environment of metalbinding sites.