摘要
利用碘乙酰胺氮氧自由基标记钙调蛋白研究了它与三氟拉嗪(TFP)、酸枣仁皂甙A(JuA)的相互作用。结果表明,每分子CaM分别至少可以结合两分子的TFP及JuA,它们的作用影响了CaM上的Met残基(主要是71,72和76)的环境,使反应自由基运动自由度的旋转相关时间τR值下降。据τR变化的趋势,推测TFP和JuA都是通过疏水作用结合到CaM上的疏水沟区,但两者的结合位点可能不同。
The interaction of trifluoperazine(TFP)and jujuboside A(JuA)with bovine calmodulin(CaM) spin-labeled at methionine residues with proxyl-iodoacetamide derivative have been studied by electron spin resonance(ESR). The results have shown that a CaM molecule can combine with at least two JuA or two TFP respectively.The binding of them affects the environments of methionine residues of CaM(most probably Met71, Met72 and Met76). The rotational correlation time τ_R of the spin labelled residues decreased on addition of JuA or TFP. It is likely that both JuA and TFP bind on CaM through hydrophobic interaction, but the binding sites and ways of binding on CaM are different.
基金
国家自然科学基金
北京分子动态资助
稳态国家重点实验室资助
关键词
调钙蛋白
自旋共振
拮抗剂
Spin label
Calmodulin
ESR
TFP
Jujuboside A
