title: Binding of chrysoidine to catalase: spectroscopy, isothermal titration calorimetry and molecular docking studies.
abstract: Chrysoidine is an industrial azo dye and the presence of chrysoidine in water and food has become an environmental concern due to its negative effects on human beings. In this work, the interactions between chrysoidine and bovine liver catalase (BLC) were explored. Obvious loss in catalytic activity was observed after incubation of BLC with chrysoidine, and the inhibition effect of BLC was found to be of the non-competitive type. No profound conformational change of BLC occurs in the presence of chrysoidine as revealed by UV-vis absorption, circular dichroism and fluorescence spectroscopy studies. Isothermal titration calorimetry results indicate that catalase has two sets of binding sites for chrysoidine. Further, molecular docking simulations show that chrysoidine is located within the bottleneck in the main channel of the substrate to the active site of BLC, which explain the activity inhibition of BLC by chrysoidine.
authors.affiliation: School of Environmental Science and Engineering, Shandong University, China-America CRC for Environment & Health, 27# Shanda Nanlu, Jinan 250100, Shandong Province, PR China.
authors.forename: Bingjun
authors.initials: B
authors.lastname: Yang
authors.forename: Fang
authors.initials: F
authors.lastname: Hao
authors.forename: Jiarong
authors.initials: J
authors.lastname: Li
authors.forename: Dongliang
authors.initials: D
authors.lastname: Chen
authors.forename: Rutao
authors.initials: R
authors.lastname: Liu
mesh_terms: D000818:Animals; D001665:Binding Sites; D002151:Calorimetry; D002374:Catalase / Q000037:antagonists & inhibitors / Q000378:metabolism*; D020134:Catalytic Domain; D002417:Cattle; D002942:Circular Dichroism; D007700:Kinetics; D008099:Liver / Q000201:enzymology; D062105:Molecular Docking Simulation; D011485:Protein Binding; D013056:Spectrophotometry, Ultraviolet; D013816:Thermodynamics; D010128:p-Aminoazobenzene / Q000031:analogs & derivatives* / Q000737:chemistry / Q000378:metabolism
chemical_list: C005562:chrysoidine; D010128:p-Aminoazobenzene; D002374:Catalase
keywords: Inhibition; Isothermal titration calorimetry; Molecular docking; Proteins; Spectroscopy; Thermodynamics