摘要
以同步荧光法研究了298,310,318K下硝苯地平(NDP)与胃蛋白酶(PEP)的荧光基团酪氨酸残基(P-Tyr)、色氨酸残基(P-Trp)之间的相互作用。表明药物以动态猝灭的方式猝灭P-Tyr、P-Trp的荧光,结合位点数n为1,主要作用力是疏水作用。310K时NDP与PEP氨基酸残基反应的荧光猝灭比率份数P-Trp53.43%>P-Tyr46.57%,结合位置更靠近P-Trp,NDP与蛋白结合率P-Tyr:69.43%～87.15%,P-Trp:73.64%～90.60%,分别建立了结合模型。且Hill系数n_H约为1,该结合与后继配体无协同作用。结合距离r都小于7nm,则NDP与P-Tyr、P-Trp之间都存在非辐射能量转移。
The interactions between fluorophore tyrosine residues（P-Tyr） and tryptophan residues （P-Tyr） of pepsin（PEP） and nifedipine（NDP） at 298, 310 and 318 K were studied by synchronous fluorescence spectroscopy. The results showed that the drug quenches the fluorescence of P-Tyr and P-Trp by means of dynamic quenching. The number of binding sites was 1, and the main force was hydrophobicity. The fluorescence quenching ratio of NDP to PEP amino acid residues at 310 K was P-Trp 53.43%〉P-Tyr 46.57%, meaning the binding site was closer to P-Trp. The binding rates of NDP to protein were P-Tyr：69.43%-87.15% and P-Trp：73.64%-90.60%, established a binding model, respectively. The Hill coefficient nH was about 1, meaning this combination has no synergistic effect with subsequent ligand. The binding distance r was less than 7 nm in both cases. Thus, non-radiative energy transfer exists between NDP and P-Tyr as well as between NDP and P-Trp.
作者
马丽花
刘保生
边刚
王春丹
张红彩
程旭
MA Li-hua;LIU Bao-sheng;BIAN Gang;WANG Chun-dan;ZHANG Hong-cai;CHENG Xu(Key Laboratory of Analytical Science and Technology of Hebei Province,College of Chemistry ＆ Environmental Science,Hebei University,Baoding 071002,China)
出处
《发光学报》
EI
CAS
CSCD
北大核心
2018年第12期1792-1798,共7页
Chinese Journal of Luminescence
基金
国家自然科学基金(21375032)资助项目~~
关键词
同步荧光法
硝苯地平
胃蛋白酶
氨基酸残基
作用机制
synchronous fluorometry
nifedipine
pepsin
amino acid residues
interaction mechanism
