A quantum-mechanical study of the reaction mechanism of sulfite oxidase.
(2014) In Journal of Biological Inorganic Chemistry 19(7). p.1165-1179- Abstract
- The oxidation of sulfite to sulfate by two different models of the active site of sulfite oxidase has been studied. Both protonated and deprotonated substrates were tested. Geometries were optimized with density functional theory (TPSS/def2-SV(P)) and energies were calculated either with hybrid functionals and large basis sets (B3LYP/def2-TZVPD) including corrections for dispersion, solvation, and entropy, or with coupled-cluster theory (LCCSD(T0)) extrapolated toward a complete basis set. Three suggested reaction mechanisms have been compared and the results show that the lowest barriers are obtained for a mechanism where the substrate attacks a Mo-bound oxo ligand, directly forming a Mo-bound sulfate complex, which then dissociates into... (More)
- The oxidation of sulfite to sulfate by two different models of the active site of sulfite oxidase has been studied. Both protonated and deprotonated substrates were tested. Geometries were optimized with density functional theory (TPSS/def2-SV(P)) and energies were calculated either with hybrid functionals and large basis sets (B3LYP/def2-TZVPD) including corrections for dispersion, solvation, and entropy, or with coupled-cluster theory (LCCSD(T0)) extrapolated toward a complete basis set. Three suggested reaction mechanisms have been compared and the results show that the lowest barriers are obtained for a mechanism where the substrate attacks a Mo-bound oxo ligand, directly forming a Mo-bound sulfate complex, which then dissociates into the products. Such a mechanism is more favorable than mechanisms involving a Mo-sulfite complex with the substrate coordinating either by the S or O atom. The activation energy is dominated by the Coulomb repulsion between the Mo complex and the substrate, which both have a negative charge of -1 or -2. (Less)
Please use this url to cite or link to this publication:
https://lup.lub.lu.se/record/4527012
- author
- Van Severen, Marie-Céline LU ; Andrejić, Milica ; Li, Jilai LU ; Starke, Kerstin LU ; Mata, Ricardo A ; Nordlander, Ebbe LU and Ryde, Ulf LU
- organization
- publishing date
- 2014
- type
- Contribution to journal
- publication status
- published
- subject
- in
- Journal of Biological Inorganic Chemistry
- volume
- 19
- issue
- 7
- pages
- 1165 - 1179
- publisher
- Springer
- external identifiers
-
- pmid:24957901
- wos:000342438100009
- pmid:24957901
- scopus:84911094229
- ISSN
- 1432-1327
- DOI
- 10.1007/s00775-014-1172-z
- language
- English
- LU publication?
- yes
- additional info
- The information about affiliations in this record was updated in December 2015. The record was previously connected to the following departments: Theoretical Chemistry (S) (011001039), Chemical Physics (S) (011001060)
- id
- b22cbc99-19c6-4200-821e-37e0935a840a (old id 4527012)
- date added to LUP
- 2016-04-01 11:02:31
- date last changed
- 2023-02-03 17:42:40
@article{b22cbc99-19c6-4200-821e-37e0935a840a, abstract = {{The oxidation of sulfite to sulfate by two different models of the active site of sulfite oxidase has been studied. Both protonated and deprotonated substrates were tested. Geometries were optimized with density functional theory (TPSS/def2-SV(P)) and energies were calculated either with hybrid functionals and large basis sets (B3LYP/def2-TZVPD) including corrections for dispersion, solvation, and entropy, or with coupled-cluster theory (LCCSD(T0)) extrapolated toward a complete basis set. Three suggested reaction mechanisms have been compared and the results show that the lowest barriers are obtained for a mechanism where the substrate attacks a Mo-bound oxo ligand, directly forming a Mo-bound sulfate complex, which then dissociates into the products. Such a mechanism is more favorable than mechanisms involving a Mo-sulfite complex with the substrate coordinating either by the S or O atom. The activation energy is dominated by the Coulomb repulsion between the Mo complex and the substrate, which both have a negative charge of -1 or -2.}}, author = {{Van Severen, Marie-Céline and Andrejić, Milica and Li, Jilai and Starke, Kerstin and Mata, Ricardo A and Nordlander, Ebbe and Ryde, Ulf}}, issn = {{1432-1327}}, language = {{eng}}, number = {{7}}, pages = {{1165--1179}}, publisher = {{Springer}}, series = {{Journal of Biological Inorganic Chemistry}}, title = {{A quantum-mechanical study of the reaction mechanism of sulfite oxidase.}}, url = {{https://lup.lub.lu.se/search/files/2332205/5266649.pdf}}, doi = {{10.1007/s00775-014-1172-z}}, volume = {{19}}, year = {{2014}}, }