Title :

Histidine versus Cysteine-Bearing Heme-Dependent Halogen Peroxidases: Parallels and Differences for Cl– Oxidation

Author(s) :

Roos, Goedele [Auteur]
Unité de Glycobiologie Structurale et Fonctionnelle UMR 8576 [UGSF]
Harvey, Jeremy N. [Auteur]
Catholic University of Leuven - Katholieke Universiteit Leuven [KU Leuven]

Journal title :

Journal of Physical Chemistry B

Abbreviated title :

J. Phys. Chem. B

Volume number :

125

Pages :

74-85

Publisher :

American Chemical Society (ACS)

Publication date :

2020-12-22

ISSN :

1520-6106

English keyword(s) :

Redox reactions
Oxidation
Bioinorganic chemistry
Peptides and proteins
Ligands

HAL domain(s) :

Sciences du Vivant [q-bio]
Chimie/Chimie théorique et/ou physique

English abstract : [en]

The homodimeric myeloperoxidase (MPO) features a histidine as a proximal ligand and a sulfonium linkage covalently attaching the heme porphyrin ring to the protein. MPO is able to catalyze Cl– oxidation with about the same ...
Show more >The homodimeric myeloperoxidase (MPO) features a histidine as a proximal ligand and a sulfonium linkage covalently attaching the heme porphyrin ring to the protein. MPO is able to catalyze Cl– oxidation with about the same efficiency as chloroperoxidase at pH 7.0. In this study, we seek to explore the parallels and differences between the histidine and cysteine heme-dependent halogen peroxidases. Transition states, reaction barriers, and relevant thermodynamic properties are calculated on protein models. Together with electronic structure calculations, it gives an overview of the reaction mechanisms and of the factors that determine the selectivity between one- and two-electron paths. Conclusions point to the innate oxidizing nature of MPO with the ester and sulfonium linkages hiking up the reactivity to enable chloride oxidation. The installation of a deprotonated imidazolate as a proximal ligand does not shift the equilibrium from one- to two-electron events without influencing the chemistry of the oxidation reaction.Show less >

Language :

Anglais

Peer reviewed article :

Oui

Audience :

Internationale

Popular science :

Non

Administrative institution(s) :

Université de Lille
CNRS

Collections :

• Unité de Glycobiologie Structurale et Fonctionnelle (UGSF) - UMR 8576

Research team(s) :

Computational Molecular Systems Biology

Submission date :

2021-03-23T13:59:31Z
2021-03-23T16:25:05Z
2022-01-21T15:27:41Z
2022-01-25T09:49:21Z