title: Stereoselective interaction of cinchona alkaloid isomers with bovine serum albumin.
abstract: The dependence of the interaction between bovine serum albumin (BSA) and two cinchona alkaloids, quinine (QN) and quinidine (QD), on the absolute configuration of these stereoisomers has been comprehensively studied. The FTIR spectra showed that QN and QD interacted with both CO and C-N groups of BSA, resulting in changes to the secondary structure of the protein. Fluorescence quenching of BSA by the stereoisomers revealed lower efficiency for QD in quenching the Trp emission of BSA when compared to QN. Further analysis accurately described the different binding behaviors and recognition discrepancies of QN and QD towards BSA, which was reflected through binding affinities, driving forces, energy changes and conformational changes during the ligand-protein interactions. Synchronous fluorescence further proved that QD was farther from Trp and Tyr than that of QN. This work could provide basic data for clarifying the binding interaction, metabolism and distribution of cinchona alkaloid stereoisomers in vivo.
authors: The State Key Lab of Structural Chemistry, Fujian Institute of Research on the Structure of Matter, Chinese Academy of Sciences, Fuzhou, Fujian 350002, People's Republic of China.
authors: Yan
authors: Y
authors: Liu
authors: Institute of Biomedical and Pharmaceutical Technology, Fuzhou University, Fuzhou, Fujian 350002, People's Republic of China.
authors: Mingmao
authors: M
authors: Chen
authors: The State Key Lab of Structural Chemistry, Fujian Institute of Research on the Structure of Matter, Chinese Academy of Sciences, Fuzhou, Fujian 350002, People's Republic of China.
authors: Longguang
authors: L
authors: Jiang
authors: The State Key Lab of Structural Chemistry, Fujian Institute of Research on the Structure of Matter, Chinese Academy of Sciences, Fuzhou, Fujian 350002, People's Republic of China. Electronic address: songling@fjirsm.ac.cn.
authors: Ling
authors: L
authors: Song
mesh_terms: D000818:Animals; D002417:Cattle; D002930:Cinchona Alkaloids / Q000737:chemistry*; D011485:Protein Binding; D017433:Protein Structure, Secondary; D012710:Serum Albumin, Bovine / Q000737:chemistry*; D013057:Spectrum Analysis / Q000379:methods*; D013237:Stereoisomerism
chemical_list: D002930:Cinchona Alkaloids; D012710:Serum Albumin, Bovine
keywords: Bovine serum albumin; Cinchona alkaloid isomers; Conformational change; Spectroscopic methods; Stereoselective binding