On the Possibility of Uphill Intramolecular Electron Transfer in Multicopper Oxidases: Electrochemical and Quantum Chemical Study of Bilirubin Oxidase
Shleev, Sergey ; Andoralov, Viktor ; Falk, Magnus ; Reimann, Curt LU ; Ruzgas, Tautgirdas ; Srnec, Martin ; Ryde, Ulf LU
and Rulisek, Lubomir
(2012)
In Electroanalysis
24(7).
p.1524-1540
- Abstract
- The catalytic cycle of multicopper oxidases (MCOs) involves intramolecular electron transfer (IET) from the Cu-T1 copper ion, which is the primary site of the one-electron oxidations of the substrate, to the trinuclear copper cluster (TNC), which is the site of the four-electron reduction of dioxygen to water. In this study we report a detailed characterization of the kinetic and electrochemical properties of bilirubin oxidase (BOx) a member of the MCO family. The experimental results strongly indicate that under certain conditions, e.g. in alkaline solutions, the IET can be the rate-limiting step in the BOx catalytic cycle. The data also suggest that one of the catalytically relevant intermediates (most likely characterized by an... (More)
- The catalytic cycle of multicopper oxidases (MCOs) involves intramolecular electron transfer (IET) from the Cu-T1 copper ion, which is the primary site of the one-electron oxidations of the substrate, to the trinuclear copper cluster (TNC), which is the site of the four-electron reduction of dioxygen to water. In this study we report a detailed characterization of the kinetic and electrochemical properties of bilirubin oxidase (BOx) a member of the MCO family. The experimental results strongly indicate that under certain conditions, e.g. in alkaline solutions, the IET can be the rate-limiting step in the BOx catalytic cycle. The data also suggest that one of the catalytically relevant intermediates (most likely characterized by an intermediate oxidation state of the TNC) formed during the catalytic cycle of BOx has a redox potential close to 0.4 V, indicating an uphill IET process from the T1 copper site (0.7 V) to the Cu-T23. These suggestions are supported by calculations of the IET rate, based on the experimentally observed Gibbs free energy change and theoretical estimates of reorganization energy obtained by combined quantum and molecular mechanical (QM/MM) calculations. (Less)
Please use this url to cite or link to this publication:
https://lup.lub.lu.se/record/3001445
- author
- Shleev, Sergey
; Andoralov, Viktor
; Falk, Magnus
; Reimann, Curt
LU
; Ruzgas, Tautgirdas
; Srnec, Martin
; Ryde, Ulf
LU
and Rulisek, Lubomir
- organization
- publishing date
- 2012
- type
- Contribution to journal
- publication status
- published
- subject
- keywords
- Bilirubin oxidase, Intramolecular electron transfer, Rate-limiting, catalytic step, Reorganization energy, QM, MM calculations
- in
- Electroanalysis
- volume
- 24
- issue
- 7
- pages
- 1524 - 1540
- publisher
- John Wiley & Sons Inc.
- external identifiers
-
- wos:000305999200006
- scopus:84863550109
- ISSN
- 1040-0397
- DOI
- 10.1002/elan.201200188
- 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), Pure and Applied Biochemistry (LTH) (011001005)
- id
- 80e1647d-5bd1-40b6-87f1-ddf900477d28 (old id 3001445)
- date added to LUP
- 2016-04-01 14:56:20
- date last changed
- 2023-01-04 07:34:09
@article{80e1647d-5bd1-40b6-87f1-ddf900477d28,
abstract = {{The catalytic cycle of multicopper oxidases (MCOs) involves intramolecular electron transfer (IET) from the Cu-T1 copper ion, which is the primary site of the one-electron oxidations of the substrate, to the trinuclear copper cluster (TNC), which is the site of the four-electron reduction of dioxygen to water. In this study we report a detailed characterization of the kinetic and electrochemical properties of bilirubin oxidase (BOx) a member of the MCO family. The experimental results strongly indicate that under certain conditions, e.g. in alkaline solutions, the IET can be the rate-limiting step in the BOx catalytic cycle. The data also suggest that one of the catalytically relevant intermediates (most likely characterized by an intermediate oxidation state of the TNC) formed during the catalytic cycle of BOx has a redox potential close to 0.4 V, indicating an uphill IET process from the T1 copper site (0.7 V) to the Cu-T23. These suggestions are supported by calculations of the IET rate, based on the experimentally observed Gibbs free energy change and theoretical estimates of reorganization energy obtained by combined quantum and molecular mechanical (QM/MM) calculations.}},
author = {{Shleev, Sergey and Andoralov, Viktor and Falk, Magnus and Reimann, Curt and Ruzgas, Tautgirdas and Srnec, Martin and Ryde, Ulf and Rulisek, Lubomir}},
issn = {{1040-0397}},
keywords = {{Bilirubin oxidase; Intramolecular electron transfer; Rate-limiting; catalytic step; Reorganization energy; QM; MM calculations}},
language = {{eng}},
number = {{7}},
pages = {{1524--1540}},
publisher = {{John Wiley & Sons Inc.}},
series = {{Electroanalysis}},
title = {{On the Possibility of Uphill Intramolecular Electron Transfer in Multicopper Oxidases: Electrochemical and Quantum Chemical Study of Bilirubin Oxidase}},
url = {{https://lup.lub.lu.se/search/files/4256782/3412392.pdf}},
doi = {{10.1002/elan.201200188}},
volume = {{24}},
year = {{2012}},
}