荧光光谱法研究β-紫罗兰酮与溶菌酶的相互作用

Investigation on the Interaction Between β-ionone and Hen Egg Lysozyme by Fluorescence Spectrometry

应用溶菌酶内源荧光光谱研究了芳香族化合物β-紫罗兰酮与卵清溶菌酶蛋白之间的结合反应,测定了两者之间的结合常数kA为1.44×103L·mol-1,结合位点数n为0.85。根据Foerster非辐射能量转移理论,确定了能量给体与受体之间的结合距离为2.27nm,符合非辐射能量转移条件。通过同步荧光光谱和三维荧光光谱,进一步研究了β-紫罗兰酮对溶菌酶蛋白构象的影响,结果显示β-紫罗兰酮的加入引起溶菌酶蛋白构象的变化,溶菌酶内部色氨酸残基所处环境的疏水性降低。

The binding interaction between the selected aroma compound,β-ionone,and hen egg lysozyme（Lys） has been studied by the intrinsic fluorescence spectrum of Lys.The combination constant kA is 1.44×103L·mol-1 and the number of binding sites n is 0.85.According to the theory of Foerster dipole-dipole energy transfer,the binding distance between β-ionone and Lys to be measured is 2.27nm which is up to the energy transfer conditions.Using the synchronous and three-dimensional fluorescence spectrum,the effect of β-ionone on the conformation of Lys was studied.The results indicated that the conformation of Lys was changed and the hydrophobic properties of the environment of tryptophan residues in Lys decreased when β-ionone was added.