title: Binding properties and structure-affinity relationships of food antioxidant butylated hydroxyanisole and its metabolites with lysozyme.
abstract: Considering the harmful impact of food antioxidants on human bodies, thoroughly exposing their potential effects at the molecular level is important. In this study, the binding interactions of butylated hydroxyanisole (BHA), a phenolic antioxidant, and its different major metabolites tert-butylhydroquinone (TBHQ) and tert-butylbenzoquinone (TBQ) with lysozyme were examined via fluorescence, three-dimensional fluorescence, circular dichroism (CD), and ligand-protein docking studies. The three compounds caused strong quenching of lysozyme fluorescence by a static quenching mechanism but with different quenching efficiencies and different effects on the α-helix content of the lysozyme. The order of binding affinity of lysozyme for all test compounds is as follows: BHA>TBQ>TBHQ. Thermodynamic parameters indicated that hydrogen bonding and van der Waals forces perform dominant functions in the binding between these compounds and lysozyme. Furthermore, structure-affinity relationships between the model compounds and lysozyme were established on the basis of computational analyses.
authors.affiliation: College of Chemical Engineering, Sichuan University, Chengdu 610065, PR China.
authors.forename: Di
authors.initials: D
authors.lastname: Wu
authors.affiliation: College of Chemical Engineering, Sichuan University, Chengdu 610065, PR China.
authors.forename: Jin
authors.initials: J
authors.lastname: Yan
authors.affiliation: College of Chemical Engineering, Sichuan University, Chengdu 610065, PR China.
authors.forename: Peixiao
authors.initials: P
authors.lastname: Tang
authors.affiliation: College of Chemical Engineering, Sichuan University, Chengdu 610065, PR China.
authors.forename: Shanshan
authors.initials: S
authors.lastname: Li
authors.affiliation: College of Chemical Engineering, Sichuan University, Chengdu 610065, PR China.
authors.forename: Kailin
authors.initials: K
authors.lastname: Xu
authors.affiliation: College of Chemical Engineering, Sichuan University, Chengdu 610065, PR China. Electronic address: lihuilab@sina.com.
authors.forename: Hui
authors.initials: H
authors.lastname: Li
mesh_terms: D000975:Antioxidants / Q000737:chemistry*; D002083:Butylated Hydroxyanisole / Q000737:chemistry*; D002942:Circular Dichroism; D005504:Food Analysis / Q000379:methods*; D006873:Hydroquinones / Q000737:chemistry; D062105:Molecular Docking Simulation; D009113:Muramidase / Q000378:metabolism*; D011485:Protein Binding; D011487:Protein Conformation; D013816:Thermodynamics
chemical_list: D000975:Antioxidants; D006873:Hydroquinones; D002083:Butylated Hydroxyanisole; C018855:2-tert-butylhydroquinone; D009113:Muramidase
keywords: Binding mode; Butylated hydroxyanisole; Lysozyme; Molecular modeling; tert-Butylbenzoquinone; tert-Butylhydroquinone