Back to Search
Start Over
Cysteine Oxidation by the Superoxide Radical: A Theoretical Study
- Source :
- ChemPhysChem, ChemPhysChem, Wiley-VCH Verlag, 2009, 10 (9-10), pp.1642-1648. 〈10.1002/cphc.200900010〉, ChemPhysChem, Wiley-VCH Verlag, 2009, 10 (9-10), pp.1642-1648. ⟨10.1002/cphc.200900010⟩, ChemPhysChem, 2009, 10 (9-10), pp.1642-1648. ⟨10.1002/cphc.200900010⟩
- Publication Year :
- 2009
- Publisher :
- Wiley, 2009.
-
Abstract
- International audience; The cysteine residue oxidation by the superoxide radical in the gas phase and in aqueous solution was studied using the integrated molecular orbital + molecular orbital (IMOMO) method combining the Quadratic Configuration Interaction (QCISD(T)) and density functional (DFT) methods. The molecular environment effects were systematically investigated by considering two alternative directions of attack of superoxide radical on the thiol and two different cysteine residue conformations. It was found that hydrogen bonding and the electrostatic interactions between the superoxide radical and cysteine side chaine significantly affect the reaction energy barrier, as compared to that derived for the simple thiol model methanethiol. Among the two possible reaction channels, that involving the sulfinyl radical formation is predicted to be the dominant channel in aqueous solution. In a highly hydrophobic environment the thiyl radical formation channel becomes the main cysteine oxidation channel.
- Subjects :
- Reaction mechanism
oxidation
Quadratic configuration interaction
Methanethiol
010402 general chemistry
Photochemistry
01 natural sciences
03 medical and health sciences
chemistry.chemical_compound
Superoxides
Molecular orbital
Physical and Theoretical Chemistry
cysteine
030304 developmental biology
chemistry.chemical_classification
0303 health sciences
Superoxide
Hydrogen bond
ab initio calculations
Atomic and Molecular Physics, and Optics
0104 chemical sciences
[CHIM.THEO]Chemical Sciences/Theoretical and/or physical chemistry
reaction mechanisms
chemistry
[ CHIM.THEO ] Chemical Sciences/Theoretical and/or physical chemistry
Thiol
Thermodynamics
superoxide
Oxidation-Reduction
Cysteine
Subjects
Details
- ISSN :
- 14397641 and 14394235
- Volume :
- 10
- Database :
- OpenAIRE
- Journal :
- ChemPhysChem
- Accession number :
- edsair.doi.dedup.....2726d47cad0b93b890504234fdbeebcb