Molecular interaction and energy transfer between human serum albumin and bioactive component Aloe dihydrocoumarin
Aloe dihydrocoumarin is an antioxidant and a candidate of immunomodulatory drug on the immune system and can balance phys-iological reactive oxygen species (ROS) levels which may be useful to maintain homeostasis. In order to explore the mechanism of drug action at a molecular level, the binding of Aloe dihydrocoumarin with human serum albumin (HSA) has been investigated by fluores-cence, ultraviolet (UV), circular dichroism (CD) and Fourier transform infrared (FT-IR) spectroscopy, fluorescence dynamics, and molecular dynamic docking for the first time. We observed a quenching of fluorescence of HSA in the presence of Aloe dihydrocoumarin and also analyzed the quenching results using the Stern-Volmer equation and obtained high affinity binding to HSA. A Forster type fluorescence resonance energy transfer mechanism is involved in this quenching of Trp fluorescence by Aloe dihydrocoumarin. From the CD and FT-IR results, it is apparent that the interaction of Aloe dihydrocoumarin with HSA causes a conformational change of the protein, with the loss of a-helix stability and the gain of β-sheet and β-turn content. Data obtained by fluorescence spectroscopy, fluorescence dynamics, CD, and FT-IR experiments along with the docking studies suggest that Aloe dihydrocoumarin binds to residues located in subdomain IIA of HSA.
Human serum albumin Aloe dihydrocoumarin Fluorescent quenching Fluorescence dynamics CD FT-IR Docking
Xiu-Feng Zhang Ling Xie Yang Liu Jun-Feng Xiang Lin Li Ya-Lin Tang
Beijing National Laboratory for Molecular Sciences, State Key Laboratory for Structural hemistry of Beijing National Laboratory for Molecular Sciences, State Key Laboratory for Structural Chemistry of Beijing National Laboratory for Molecular Sciences, State Key Laboratory for Structural Chemistry of
国际会议
广州
英文
102-108
2008-11-01（万方平台首次上网日期，不代表论文的发表时间）