The reaction mechanism of iron and manganese superoxide dismutases studied by theoretical calculations
Rulisek, Lubomir LU ; Jensen, Kasper LU ; Lundgren, Kristoffer and Ryde, Ulf LU
(2006)
In Journal of Computational Chemistry
27(12).
p.1398-1414
- Abstract
- We have studied the detailed reaction mechanism of iron and manganese superoxide dismutase with density functional calculations on realistic active-site models, with large basis sets and including solvation, zero-point, and thermal effects. The results indicate that the conversion of O-2(-) to O-2 follows an associative mechanism, with O-2 directly binding to the metal, followed by the protonation of the metal-bound hydroxide ion, and the dissociation of O-3(2). All these reaction steps are exergonic. Likewise, we suggest that the conversion of O-2(-) to H2O2 follows an at least a partly second-sphere pathway. There are small differences in the preferred oxidation and spin states, as well as in the geometries, of Fe and Mn, but these... (More)
- We have studied the detailed reaction mechanism of iron and manganese superoxide dismutase with density functional calculations on realistic active-site models, with large basis sets and including solvation, zero-point, and thermal effects. The results indicate that the conversion of O-2(-) to O-2 follows an associative mechanism, with O-2 directly binding to the metal, followed by the protonation of the metal-bound hydroxide ion, and the dissociation of O-3(2). All these reaction steps are exergonic. Likewise, we suggest that the conversion of O-2(-) to H2O2 follows an at least a partly second-sphere pathway. There are small differences in the preferred oxidation and spin states, as well as in the geometries, of Fe and Mn, but these differences have little influence on the energetics, and therefore on the reaction mechanism of the two types of superoxide dismutases. For example, the two metals have very similar reduction potentials in the active-site models, although they differ by 0.7 V in water solution. The reaction mechanisms and spin states seem to have been designed to avoid spin conversions or to facilitate them by employing nearly degenerate spin states. (c) 2006 Wiley Periodicals, Inc. (Less)
Please use this url to cite or link to this publication:
https://lup.lub.lu.se/record/402189
- author
- Rulisek, Lubomir
LU
; Jensen, Kasper
LU
; Lundgren, Kristoffer
and Ryde, Ulf
LU
- organization
- publishing date
- 2006
- type
- Contribution to journal
- publication status
- published
- subject
- keywords
- superoxide dismutase, iron, manganese, reaction mechanisms
- in
- Journal of Computational Chemistry
- volume
- 27
- issue
- 12
- pages
- 1398 - 1414
- publisher
- John Wiley & Sons Inc.
- external identifiers
-
- wos:000239072600014
- scopus:33747201345
- ISSN
- 1096-987X
- DOI
- 10.1002/jcc.20450
- 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)
- id
- 8f523727-a1b6-47de-9459-20af5fd3b90e (old id 402189)
- date added to LUP
- 2016-04-01 16:51:23
- date last changed
- 2023-01-24 02:30:24
@article{8f523727-a1b6-47de-9459-20af5fd3b90e,
abstract = {{We have studied the detailed reaction mechanism of iron and manganese superoxide dismutase with density functional calculations on realistic active-site models, with large basis sets and including solvation, zero-point, and thermal effects. The results indicate that the conversion of O-2(-) to O-2 follows an associative mechanism, with O-2 directly binding to the metal, followed by the protonation of the metal-bound hydroxide ion, and the dissociation of O-3(2). All these reaction steps are exergonic. Likewise, we suggest that the conversion of O-2(-) to H2O2 follows an at least a partly second-sphere pathway. There are small differences in the preferred oxidation and spin states, as well as in the geometries, of Fe and Mn, but these differences have little influence on the energetics, and therefore on the reaction mechanism of the two types of superoxide dismutases. For example, the two metals have very similar reduction potentials in the active-site models, although they differ by 0.7 V in water solution. The reaction mechanisms and spin states seem to have been designed to avoid spin conversions or to facilitate them by employing nearly degenerate spin states. (c) 2006 Wiley Periodicals, Inc.}},
author = {{Rulisek, Lubomir and Jensen, Kasper and Lundgren, Kristoffer and Ryde, Ulf}},
issn = {{1096-987X}},
keywords = {{superoxide dismutase; iron; manganese; reaction mechanisms}},
language = {{eng}},
number = {{12}},
pages = {{1398--1414}},
publisher = {{John Wiley & Sons Inc.}},
series = {{Journal of Computational Chemistry}},
title = {{The reaction mechanism of iron and manganese superoxide dismutases studied by theoretical calculations}},
url = {{https://lup.lub.lu.se/search/files/135493558/84_sod.pdf}},
doi = {{10.1002/jcc.20450}},
volume = {{27}},
year = {{2006}},
}