时间分辨荧光研究姜黄素-肌红蛋白复合物的变性和复性。

Time-resolved fluorescence study during denaturation and renaturation of curcumin-myoglobin complex.

机构信息

Department of Chemistry, American University of Beirut, Beirut, Lebanon.

出版信息

Int J Biol Macromol. 2012 May 1;50(4):885-90. doi: 10.1016/j.ijbiomac.2012.02.010. Epub 2012 Feb 17.

DOI:10.1016/j.ijbiomac.2012.02.010

Abstract

Curcumin influences the transition point, the concentration of denaturant required to effect 50% of the total change, of myoglobin denaturation. Curcumin enhances absorbance of myoglobin at 280 nm with a binding constant K=3.0×10(4) M(-1) whereas fluorescence of curcumin is quenched by myoglobin with a Stern-Volmer association constant of 2.5×10(5) M(-1). Unfolding process of myoglobin-curcumin induces a recovery in fluorescence lifetime loss. The gain in time-resolved fluorescence lifetime during unfolding has been again lost during refolding of curcumin-myoglobin complex by dilution process suggesting partial reversibility of unfolding process for both myoglobin and curcumin-myoglobin complex.

摘要

姜黄素影响肌红蛋白变性的转变点，即达到总变化 50%所需的变性剂浓度。姜黄素增强了肌红蛋白在 280nm 处的吸光度，结合常数 K=3.0×10(4) M(-1)，而肌红蛋白猝灭了姜黄素的荧光，斯特恩-沃尔默缔合常数为 2.5×10(5) M(-1)。肌红蛋白-姜黄素的展开过程诱导荧光寿命损失的恢复。在稀释过程中通过展开使姜黄素-肌红蛋白复合物重新折叠，恢复了时间分辨荧光寿命的增加，表明肌红蛋白和姜黄素-肌红蛋白复合物的展开过程具有部分可逆性。