title: Combined spectroscopies and molecular docking approach to characterizing the binding interaction of enalapril with bovine serum albumin.
abstract: The binding interaction between bovine serum albumin (BSA) and enalapril (ENPL) at the imitated physiological conditions (pH = 7.4) was investigated using UV-vis absorption spectroscopy (UV-vis), fluorescence emission spectroscopy (FES), synchronous fluorescence spectroscopy (SFS), Fourier transform infrared spectroscopy (FT-IR), circular dichroism (CD) and molecular docking methods. It can be deduced from the experimental results from the steady-state fluorescence spectroscopic titration that the intrinsic BSA fluorescence quenching mechanism induced by ENPL is static quenching, based on the decrease in the BSA quenching constants in the presence of ENPL with increase in temperature and BSA quenching rates >1010L mol-1sec-1. This result indicates that the ENPL-BSA complex is formed through an intermolecular interaction of ENPL with BSA. The main bonding forces for interaction of BSA and ENPL are van der Waal's forces and hydrogen bonding interaction based on negative values of Gibbs free energy change (ΔG0), enthalpic change (ΔH0) and entropic change (ΔS0). The binding of ENPL with BSA is an enthalpy-driven process due to |ΔH°| > |TΔS°| in the binding process. The results of competitive binding experiments and molecular docking confirm that ENPL binds in BSA sub-domain IIA (site I) and results in a slight change in BSA conformation, but BSA still retains its α-helical secondary structure.
authors.affiliation: College of Pharmaceutical Science, Zhejiang University of Technology, Hangzhou, 310032, China.
authors.forename: Dong-Qi
authors.initials: DQ
authors.lastname: Pan
authors.affiliation: College of Pharmaceutical Science, Zhejiang University of Technology, Hangzhou, 310032, China.
authors.forename: Min
authors.initials: M
authors.lastname: Jiang
authors.affiliation: College of Pharmaceutical Science, Zhejiang University of Technology, Hangzhou, 310032, China.
authors.forename: Ting-Ting
authors.initials: TT
authors.lastname: Liu
authors.affiliation: College of Pharmaceutical Science, Zhejiang University of Technology, Hangzhou, 310032, China.
authors.forename: Qi
authors.initials: Q
authors.lastname: Wang
authors.affiliation: College of Pharmaceutical Science, Zhejiang University of Technology, Hangzhou, 310032, China.|State Key Laboratory Breeding Base of Green Chemistry Synthesis Technology, Zhejiang University of Technology, Hangzhou, 310032, China.
authors.forename: Jie-Hua
authors.initials: JH
authors.lastname: Shi
mesh_terms: D001665:Binding Sites; D001667:Binding, Competitive; D002942:Circular Dichroism; D004656:Enalapril / Q000737:chemistry / Q000378:metabolism*; D006860:Hydrogen Bonding; D062105:Molecular Docking Simulation / Q000379:methods*; D011487:Protein Conformation; D012710:Serum Albumin, Bovine / Q000737:chemistry* / Q000378:metabolism*; D013050:Spectrometry, Fluorescence; D013056:Spectrophotometry, Ultraviolet; D017550:Spectroscopy, Fourier Transform Infrared; D013696:Temperature; D013816:Thermodynamics
chemical_list: D012710:Serum Albumin, Bovine; D004656:Enalapril
keywords: bovine serum albumin; enalaprilS; interaction; molecular docking; spectroscopic techniques