Computational Modeling of the Catalytic Cycle of Glutathione Peroxidase Nanomimic
| Autor: | Mohammad Izadyar, Ramesh Kheirabadi |
|---|---|
| Rok vydání: | 2016 |
| Předmět: |
Azoles
Models Molecular Reaction mechanism Selenenic acid Isoindoles 010402 general chemistry Photochemistry 01 natural sciences chemistry.chemical_compound Organoselenium Compounds Physical and Theoretical Chemistry chemistry.chemical_classification Glutathione Peroxidase Molecular Structure 010405 organic chemistry Chemistry Ebselen Glutathione peroxidase Atoms in molecules 0104 chemical sciences Nanostructures Catalytic cycle Covalent bond Biocatalysis Enzyme mimic Quantum Theory |
| Zdroj: | The journal of physical chemistry. A. 120(51) |
| ISSN: | 1520-5215 |
| Popis: | To elucidate the role of a derivative of ebselen as a mimic of the antioxidant selenoenzyme glutathione peroxidase, density functional theory and solvent-assisted proton exchange (SAPE) were applied to model the reaction mechanism in a catalytic cycle. This mimic plays the role of glutathione peroxidase through a four-step catalytic cycle. The first step is described as the oxidation of 1 in the presence of hydrogen peroxide, while selenoxide is reduced by methanthiol at the second step. In the third step of the reaction, the reduction of selenenylsulfide occurs by methanthiol, and the selenenic acid is dehydrated at the final step. Based on the kinetic parameters, step 4 is the rate-determining step (RDS) of the reaction. The bond strength of the atoms involved in the RDS is discussed with the quantum theory of atoms in molecules (QTAIM). Low value of electron density, ρ(r), and positive Laplacian values are the evidence for the covalent nature of the hydrogen bonds rupture (O30–H31, O33–H34). A change i... |
| Databáze: | OpenAIRE |
| Externí odkaz: |
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