Probing the interactions of hemoglobin with antioxidant flavonoids via fluorescence spectroscopy and molecular modeling studies
Probing the interactions of hemoglobin with antioxidant flavonoids via fluorescence spectroscopy and molecular modeling studies
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DOI：
10.1016/j.bpc.2010.12.003
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发表时间：
2011-02-01
影响因子：
3.8
通讯作者：
Sengupta, Pradeep K.
中科院分区：
文献类型：
--
作者：
Chaudhuri, Sudip;Chakraborty, Sandipan;Sengupta, Pradeep K.
稳态和时间分辨荧光光谱，结合分子模拟计算，已被用来探索两种治疗上重要的黄酮类化合物，非瑟酮（3，7，3 '，4'-OH-黄酮）和3-羟基黄酮（3-HF），与正常人血红蛋白（HbA）的相互作用。非瑟酮和3-HF独特的“双色”荧光特征和相当高的荧光各向异性（r = 0.12-0.28）揭示了它们与HbA的特异性相互作用。根据荧光研究估计的非瑟酮和3-HF的结合常数分别约为4.00 × 10（4）M-1和9.83 × 10（3）M-1。与HbA的特异性相互作用进一步从类黄酮诱导的蛋白色氨酸荧光的静态猝灭中得到证实，如以下所示：（a）双分子猝灭常数K-q >>扩散控制极限（B）Stern-Volmer猝灭常数和结合常数的值密切匹配（c）tau（o）/tau接近1（其中tau（o）和tau分别是未猝灭和猝灭的色氨酸荧光寿命）。分子对接和静电表面电位计算揭示了非瑟酮和3-HF与HbA的对比结合模式。(C)2010 Elsevier BV保留所有权利。
Steady state and time resolved fluorescence spectroscopy, combined with molecular modeling computations, have been used to explore the interactions of two therapeutically important flavonoids, fisetin (3,7,3',4'-OH-flavone) and 3-hydroxyflavone (3-HF), with normal human hemoglobin (HbA). Distinctive 'two color' fluorescence signatures and fairly high fluorescence anisotropy (r = 0.12-0.28) of fisetin and 3-HF reveal their specific interactions with HbA. Binding constants estimated from the fluorescence studies were approximate to 4.00 x 10(4) M-1 and 9.83 x 10(3) M-1 for fisetin and 3-HF respectively. Specific interactions with HbA were further confirmed from flavonoid-induced static quenching of the protein tryptophan fluorescence as indicated by: (a) bimolecular quenching constant K-q >> diffusion controlled limit (b) closely matched values of Stern-Volmer quenching constant and binding constant (c) tau(o)/tau approximate to 1 (where tau(o) and tau are the unquenched and quenched tryptophan fluorescence lifetimes respectively). Molecular docking and electrostatic surface potential calculations reveal contrasting binding modes of fisetin and 3-HF with HbA. (C) 2010 Elsevier B.V. All rights reserved.