title: Determination of the specific interaction between palmatine and bovine serum albumin.
abstract: The binding of palmatine to bovine serum albumin (BSA) was studied under physiological conditions (pH = 7.40) by molecular spectroscopic approach. It was proved that the fluorescence quenching of BSA by palmatine is a result of the formation of palmatine-BSA complex. Binding parameters were determined using the modified Stern-Volmer equation and Scatchard equation, to measure the specific binding between palmatine and BSA. The thermodynamic parameters calculated, ∆G°, ∆H° and ∆S° indicate that the electrostatic interactions play a major role in the palmatine-BSA association. Site marker competitive displacement experiments demonstrated that palmatine binds with specific affinity to site II (subdomain IIIA) of BSA. Furthermore, the specific binding distance r (3.36 nm) was obtained according to fluorescence resonance energy transfer. The results of synchronous fluorescence spectra and UV-Visible absorption spectra show that the conformation of bovine serum albumin has been changed.
authors.affiliation: Hubei Key Laboratory of Pollutant Analysis & Reuse Technology, Department of Chemistry, Hubei Normal University, Huangshi, 435002, People's Republic of China.
authors.forename: Yu
authors.initials: Y
authors.lastname: Ou-Yang
authors.forename: Xiao-Ling
authors.initials: XL
authors.lastname: Li
authors.forename: Hong
authors.initials: H
authors.lastname: Wang
authors.forename: Min
authors.initials: M
authors.lastname: Fang
authors.forename: Yan-Jun
authors.initials: YJ
authors.lastname: Hu
mesh_terms: D000818:Animals; D001600:Berberine Alkaloids / Q000737:chemistry / Q000378:metabolism*; D001665:Binding Sites; D001667:Binding, Competitive; D002417:Cattle; D007700:Kinetics; D011485:Protein Binding; D015203:Reproducibility of Results; D012710:Serum Albumin, Bovine / Q000378:metabolism*; D013050:Spectrometry, Fluorescence; D013056:Spectrophotometry, Ultraviolet; D013696:Temperature
chemical_list: D001600:Berberine Alkaloids; D012710:Serum Albumin, Bovine; C005413:palmatine