title: Specific binding and inhibition of 6-benzylaminopurine to catalase: multiple spectroscopic methods combined with molecular docking study.
abstract: 6-Benzylaminopurine (6-BA) is a kind of cytokinin which could regulate the activities of the antioxidant defense system of plants. In this work, its interaction with and inhibition of beef liver catalase have been systematically investigated using spectroscopic, isothermal titration calorimetric and molecular docking methods under physiological conditions. The fluorescence quenching of beef liver catalase (BLC) by 6-BA is due to the formation of 6-BA-BLC complex. Hydrogen bonds and van der Waals interactions play major roles in stabilizing the complex. The Stern-Volmer quenching constant, binding constant, the corresponding thermodynamic parameters and binding numbers were measured. The results of UV-vis absorption, three-dimensional fluorescence, synchronous fluorescence and circular dichroism spectroscopic results demonstrate that the binding of 6-BA results in the micro-environment change around tyrosine (Tyr) and tryptophan (Trp) residues of BLC. The BLC-mediated conversion of H2O2 to H2O and O2, in the presence and absence of 6-BA, was also studied. Lineweaver-Burk plot indicates a noncompetitive type of inhibition. Molecular docking study was used to find the binding sites.
authors.affiliation: College of Chemistry and Chemical Engineering, Yangzhou University, Yangzhou 225002, China. Electronic address: yz_xiner@163.com.
authors.forename: Qin
authors.initials: Q
authors.lastname: Xu
authors.affiliation: College of Chemistry and Chemical Engineering, Yangzhou University, Yangzhou 225002, China.
authors.forename: Yanni
authors.initials: Y
authors.lastname: Lu
authors.affiliation: College of Chemistry and Chemical Engineering, Yangzhou University, Yangzhou 225002, China.
authors.forename: Longyun
authors.initials: L
authors.lastname: Jing
authors.affiliation: College of Chemistry and Chemical Engineering, Yangzhou University, Yangzhou 225002, China.
authors.forename: Lijuan
authors.initials: L
authors.lastname: Cai
authors.affiliation: College of Information Technology, Yangzhou University, Yangzhou 225127, China.
authors.forename: Xinfeng
authors.initials: X
authors.lastname: Zhu
authors.affiliation: College of Chemistry and Chemical Engineering, Yangzhou University, Yangzhou 225002, China.
authors.forename: Ju
authors.initials: J
authors.lastname: Xie
authors.affiliation: College of Chemistry and Chemical Engineering, Yangzhou University, Yangzhou 225002, China. Electronic address: xyhu@yzu.edu.cn.
authors.forename: Xiaoya
authors.initials: X
authors.lastname: Hu
mesh_terms: D000818:Animals; D001593:Benzyl Compounds; D002374:Catalase / Q000737:chemistry / Q000378:metabolism*; D002417:Cattle; D007701:Kinetin / Q000737:chemistry / Q000378:metabolism*; D008099:Liver / Q000201:enzymology; D062105:Molecular Docking Simulation; D011485:Protein Binding; D011487:Protein Conformation; D011687:Purines; D013816:Thermodynamics
chemical_list: D001593:Benzyl Compounds; D011687:Purines; D002374:Catalase; C480551:benzylaminopurine; D007701:Kinetin
keywords: 6-Benzylaminopurine; Catalase; Docking; Inhibition; Interaction