Radu, V, Frielingsdorf, S, Lenz, O et al. (1 more author) (2016) Reactivation from the Ni-B state in [NiFe] hydrogenase of Ralstonia eutropha is controlled by reduction of the superoxidised proximal cluster. Chemical Communications, 52 (12). pp. 2632-2635. ISSN 1359-7345
Abstract
The tolerance towards oxic conditions of O2-tolerant [NiFe] hydrogenases has been attributed to an unusual [4Fe–3S] cluster that lies proximal to the [NiFe] active site. Upon exposure to oxygen, this cluster converts to a superoxidised (5+) state, which is believed to secure the formation of the so-called Ni–B state that is rapidly reactivated under reducing conditions. Here, the reductive reactivation of the membrane-bound [NiFe]-hydrogenase (MBH) from Ralstonia eutropha in a native-like lipid membrane was characterised and compared to a variant that instead carries a typical [4Fe–4S] proximal cluster. Reactivation from the Ni–B state was faster in the [4Fe–4S] variant, suggesting that the reactivation rate in MBH is limited by the reduction of the superoxidised [4Fe–3S] cluster. We propose that the [4Fe–3S] cluster plays a major role in protecting MBH by blocking the reversal of electron transfer to the [NiFe] active site, which would produce damaging radical oxygen species.
Metadata
Item Type: | Article |
---|---|
Authors/Creators: |
|
Copyright, Publisher and Additional Information: | © 2016, the Author(s). This article is licensed under a Creative Commons Attribution 3.0 Unported Licence. |
Dates: |
|
Institution: | The University of Leeds |
Academic Units: | The University of Leeds > Faculty of Biological Sciences (Leeds) |
Funding Information: | Funder Grant number EU - European Union 280518 |
Depositing User: | Symplectic Publications |
Date Deposited: | 11 Feb 2016 15:52 |
Last Modified: | 11 Feb 2016 15:52 |
Published Version: | http://dx.doi.org/10.1039/C5CC10382G |
Status: | Published |
Publisher: | Royal Society of Chemistry |
Identification Number: | 10.1039/C5CC10382G |
Open Archives Initiative ID (OAI ID): | oai:eprints.whiterose.ac.uk:94567 |