title: Spectroscopic and molecular docking studies of binding interaction of gefitinib, lapatinib and sunitinib with bovine serum albumin (BSA).
abstract: The binding interactions of three kinds of tyrosine kinase inhibitors (TKIs), such as gefitinib, lapatinib and sunitinib, with bovine serum albumin (BSA) were studied using ultraviolet spectrophotometry, fluorescence spectroscopy, circular dichroism (CD), Fourier transform infrared spectroscopy (FT-IR) and molecular docking methods. The experimental results showed that the intrinsic fluorescence quenching of BSA induced by the three TKIs resulted from the formation of stable TKIs-BSA complexes through the binding interaction of TKIs with BSA. The stoichiometry of three stable TKIs-BSA complexes was 1:1 and the binding constants (Kb) of the three TKIs-BSA complexes were in the order of 10(4)M(-1) at 310 K, indicating that there was a strong binding interaction of the three TKIs with BSA. Based on the analysis of the signs and magnitudes of the free energy change (ΔG(0)), enthalpic change (ΔH(0)) and entropic change (ΔS(0)) in the binding process, it can be deduced that the binding process of the three TKIs with BSA was spontaneous and enthalpy-driven process, and the main interaction forces between the three TKIs and BSA were van der Waals force and hydrogen bonding interaction. Moreover, from the results of CD, FT-IR and molecular docking, it can be concluded that there was a significant difference between the three TKIs in the binding site on BSA, lapatinib was located on site II (m) of BSA while gefitinib and sunitinib were bound on site I of BSA, and there were some changes in the BSA conformation when binding three TKIs to BSA but BSA still retains its secondary structure α-helicity.
authors.affiliation: College of Pharmaceutical Science, Zhejiang University of Technology, Hangzhou 310032, China.
authors.forename: Guo-Feng
authors.initials: GF
authors.lastname: Shen
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.
authors.forename: Min
authors.initials: M
authors.lastname: Jiang
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. Electronic address: shijh@zjut.edu.cn.
authors.forename: Jie-Hua
authors.initials: JH
authors.lastname: Shi
mesh_terms: D000818:Animals; D001665:Binding Sites; D002417:Cattle; D002942:Circular Dichroism; D031541:Fluorescence Resonance Energy Transfer; D000077156:Gefitinib; D007211:Indoles / Q000737:chemistry / Q000378:metabolism*; D000077341:Lapatinib; D062105:Molecular Docking Simulation; D011485:Protein Binding; D017434:Protein Structure, Tertiary; D011758:Pyrroles / Q000737:chemistry / Q000378:metabolism*; D011799:Quinazolines / Q000737:chemistry / Q000378:metabolism*; D012710:Serum Albumin, Bovine / Q000737:chemistry / Q000378:metabolism*; D013056:Spectrophotometry, Ultraviolet; D017550:Spectroscopy, Fourier Transform Infrared; D000077210:Sunitinib; D013816:Thermodynamics
chemical_list: D007211:Indoles; D011758:Pyrroles; D011799:Quinazolines; D000077341:Lapatinib; D012710:Serum Albumin, Bovine; D000077156:Gefitinib; D000077210:Sunitinib
keywords: Binding interaction; Bovine serum albumin; Gefitinib; Lapatinib; Sunitinib