有机氯农药与牛血清白蛋白作用机理研究

利用荧光光谱法研究了5种有机氯农药（OCPs） δ-BHC、α-氯丹、艾氏剂、o,p＇-DDT、HCB和牛血清白蛋白（BSA）的相互作用机理.280 nm波长下,OCPs可使BSA色氨酸残基发生荧光猝灭现象.通过光谱数据,绘制了Stern-Volmer曲线,测定了平衡常数和25,37℃下OCPs-BSA的结合常数.结果显示,5种OCPs猝灭蛋白质的过程均为熵驱动的静态猝灭过程,通过较弱的疏水作用力与蛋白质相互结合,结合点位数近似为1,这种结合作用会随着温度的升高而增强.

Study on the interaction of organochlorine pesticides with bovine serum albumin

Molecular fluorescence spectrometry was applied to study the interaction of five organochlorine pesticides （OCPs） （6-BHC, a-chlordane, HCB, Aldrin, o,p＇-DDT） with bovine serum albumin （BSA）. The fluorescence of tryptophan residues with a 280 nm wavelength light, and observed quenching by titrating BSA solutions with OCPs. Stern-Volmer graphs were plotted and quenching constants were estimated. Results pointed to the formation of complexes of OCPs with BSA. Association constants at 25 ℃ and 37 ℃ were measured for five OCPs, respectively. Results suggest that the probable quenching mechanisms of fluorescence of BSA by OCPs were all static quenching procedures, the binding reactions were mainly entropy-driven, and hydrophobic interactions played a major role in the reaction.