光谱法研究阿维菌素与溶菌酶的相互作用

Spectrctroscopic studies on the interaction between avermectin and Lysozyme

为研究阿维菌素残留被生物体吸收后,在生物体内的作用机理,在模拟生理条件下,应用荧光光谱、圆二色谱和同步荧光研究阿维菌素与溶菌酶相互作用的活性机理。研究表明,阿维菌素与溶菌酶的作用机理为荧光静态猝灭;两者通过氢键和范德华力形成1︰1结合,结合距离为4.55 nm;298、303和308 K时的结合常数分别为1.10×105、1.08×105和0.38×105 L·mol−1,结合强度紧密;同步荧光和圆二色谱证实阿维菌素影响溶菌酶的二级结构,使溶菌酶分子α-螺旋结构含量减小。本文为农药残留在生物体内中代谢过程、解毒和指导科学使用农药提供理论依据。

To investigate interactions between avermectin pesticide residues with protein,the interaction between avermectin and Lysozyme is studied in physiological conditions by spectroscopic methods.It is shown that fluorescence quenching mechanism of avermectin with Lysozyme is a static quenching procedure,the interaction are mainly the hydrogen bond and Van der Waals force;The distance between them is 4.55 nm by Förster non-radiative energy transfer theory and the apparent binding constants(KA)are 1.10×105(298 K)、1.08×105(303 K)and 0.38×105(308 K)L·mol−1,the binding sites(n)is 1;The results of CD spectra and the synchronous fluorescence indicated that the secondary structure of Lysozyme is changed when avermectin bound to Lysozyme,the content ofα-helical structure decreased.This study provides theoretical reference for the transport,metabolism and poisoning mechanism of residual pesticides,and provide guidance for the scientific and effective use of pesticides.