Spectroscopic and Molecular Docking Approaches for Investigation of Interaction of Phellopterin with Human Serum Albumin

Publication date: March 2019Source: Chinese Journal of Analytical Chemistry, Volume 47, Issue 3Author(s): Tuan-Wu CAO, Xiao-Ping TAN, Lu-Ping HUANG, Jian-Wei SHI, Gang XUAbstractThe mechanism of interaction between human serum albumin (HSA) and natural product phellopterin (PL) from Angelica dahurica was investigated by spectroscopic techniques with molecular docking under simulated physiological conditions. The experimental results showed that the fluorescence of HSA was regularly quenched by PL, and the quenching constants (KSV) decreased with increasing temperature, which indicated that the quenching mechanism was a static quenching procedure. The binding constants (KA) were larger than 10−5 M−1 and the number of binding sites (n) was approximate to 1 at different temperatures, which indicated that the binding affinity was hige and there was just one main binding site in HSA for PL. According to thermodynamic parameters from Van't Hoff equation, the binding process of PL with HSA was spontaneous and exothermic process due to ΔG < 0, and the electrostatic force played major role in the binding between PL and HSA according to ΔH < 0 and ΔS> 0. The binding distance (r) was calculated to be about 3.35 nm, which implied that the energy transfer from HSA to PL occurred with high possibility according to the theory of Förster's non-radiation energy transfer. The microenvironment and conformation of HSA changed with the addition of PL based on the results of synchr...

Source: Chinese Journal of Analytical Chemistry - March 9, 2019 Category: Chemistry Source Type: research