title: Study on the binding of chlorogenic acid to pepsin by spectral and molecular docking.
abstract: The interaction of pepsin with chlorogenic acid (CHA) was investigated using fluorescence, UV/vis spectroscopy and molecular modeling methods. Stern-Volmer analysis indicated that the fluorescence quenching of pepsin by CHA resulted from a static mechanism, and the binding constant was 1.1846 × 10(5) and 1.1587 × 10(5) L/mol at 288 and 310 K, respectively. The distance between donor (pepsin) and acceptor (CHA) was calculated to be 2.39 nm and the number of binding sites for CHA binding on pepsin was ~ 1. The results of synchronous fluorescence and three-dimensional fluorescence showed that binding of CHA to pepsin could induce conformational changes in pepsin. Molecular docking experiments found that CHA bonded with pepsin in the area of the hydrophobic cavity with Van der Waals' forces or hydrogen bonding interaction, which were consistent with the results obtained from the thermodynamic parameter analysis. Furthermore, the binding of CHA can inhibit pepsin activity in vitro.
authors: School of Pharmaceutical Sciences, Zhengzhou University, Zhengzhou, 450001, People's Republic of China.
authors: Hua-jin
authors: HJ
authors: Zeng
authors: Hui-li
authors: HL
authors: Liang
authors: Jing
authors: J
authors: You
authors: Ling-bo
authors: LB
authors: Qu
mesh_terms: D001665:Binding Sites; D002726:Chlorogenic Acid / Q000737:chemistry*; D005453:Fluorescence; D062105:Molecular Docking Simulation; D015394:Molecular Structure; D010434:Pepsin A / Q000737:chemistry*; D013050:Spectrometry, Fluorescence; D013056:Spectrophotometry, Ultraviolet
chemical_list: D002726:Chlorogenic Acid; D010434:Pepsin A
keywords: chlorogenic acid (CHA); enzyme activity; fluorescence spectroscopy; molecular docking; pepsin