3-[2-(5-溴-噻吩基)]-1-苯基-2-丙烯酮与牛血清白蛋白的相互作用

The interaction of 3-[2-(5-Bromo-thienyl)]-1-phenyl-2-propenone with bovine serum albumin

通过苯乙酮和5-溴噻吩-2-甲醛合成了3-[2-(5-溴-噻吩基)]-1-苯基-2-丙烯酮(BTPPO)。使用光谱法和分子对接模拟研究了BTPPO与牛血清白蛋白(BSA,bovine serum albumin)的作用过程。同时,研究了金属离子(Cu^(2+),Co^(2+),Pb^(2+),Ag^(+),Hg^(2+),Cd^(2+))对BTPPO与BSA相互作用的影响。结果表明:BTPPO与BSA的作用主要是静态荧光淬灭过程,两者之间的结合以疏水和静电作用为主,结合常数(K_(a))为10^(4)左右。根据Forster理论,可以计算得BTPPO和BSA的共振能量转移距离小于7 nm。另外,在280 nm和295 nm激发波长下蛋白质的荧光淬灭实验表明:BTPPO与BSA的主要结合位点是BSA的亚结构域ⅡA(siteⅠ)。金属离子(Pb^(2+)除外)的存在可能会影响BTPPO荧光淬灭效果。分子对接模拟结果表明:BTPPO是通过疏水和极性作用嵌入BSA分子的亚结构域ⅡA(siteⅠ)的疏水腔内的。

3-[2-(5-Bromo-thienyl)]-1-phenyl-2-propenone(BTPPO)was synthesized from acetophenone and 5-bromothiophene-2-carbaldehyde.The spectrometric and molecular docking were employed to investigate the binding mechanism of BTPPO to bovine serum albumin(BSA),and the effects of metal ions(Cu^(2+),Co^(2+),Pb^(2+),Ag^(+),Hg^(2+),Cd^(2+))on the BTPPO-BSA binding system were also discussed.The spectrometric experiment results showed that the binding reaction of BTPPO to BSA was based on the static fluorescence-quenching process with hydrophobic and electrostatic forces,and the binding constant(Ka)was about 10^(4).Based on the Förster theory,the binding distance(r)between BTPPO and BSA was less than 7 nm.Comparing the quenching of protein fluorescence excited at 280 nm and 295 nm,it was shown that the primary BTPPO binding site was located in the sub-domainⅡA(siteⅠ)of BSA.The presence of metal ions(except Pb^(2+))may influence the BTPPO efficacy.The molecule docking results illustrated that BTPPO can bind with the sub-domainⅡA of BSA in which hydrophobic and polar interactions are the key acting force.