Gopalasingam, GC, Johnson, RM, Chiduza, GN et al. (6 more authors) (2019) Dimeric structures of quinol-dependent nitric oxide reductases (qNORs) revealed by cryo–electron microscopy. Science Advances, 5 (8). eaax1803. ISSN 2375-2548
Abstract
Quinol-dependent nitric oxide reductases (qNORs) are membrane-integrated, iron-containing enzymes of the denitrification pathway, which catalyze the reduction of nitric oxide (NO) to the major ozone destroying gas nitrous oxide (N2O). Cryo–electron microscopy structures of active qNOR from Alcaligenes xylosoxidans and an activity-enhancing mutant have been determined to be at local resolutions of 3.7 and 3.2 Å, respectively. They unexpectedly reveal a dimeric conformation (also confirmed for qNOR from Neisseria meningitidis) and define the active-site configuration, with a clear water channel from the cytoplasm. Structure-based mutagenesis has identified key residues involved in proton transport and substrate delivery to the active site of qNORs. The proton supply direction differs from cytochrome c–dependent NOR (cNOR), where water molecules from the cytoplasm serve as a proton source similar to those from cytochrome c oxidase.
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Item Type: | Article |
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Authors/Creators: |
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Copyright, Publisher and Additional Information: | © 2019 The Authors, some rights reserved; exclusive licensee American Association for the Advancement of Science. No claim to original U.S. Government Works. Distributed under a Creative Commons Attribution License 4.0 (CC BY). This is an open-access article distributed under the terms of the Creative Commons Attribution license, which permits unrestricted use, distribution, and reproduction in any medium, provided the original work is properly cited. |
Dates: |
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Institution: | The University of Leeds |
Academic Units: | The University of Leeds > Faculty of Biological Sciences (Leeds) > School of Biomedical Sciences (Leeds) |
Funding Information: | Funder Grant number Wellcome Trust 109158/B/15/Z |
Depositing User: | Symplectic Publications |
Date Deposited: | 03 Jul 2019 15:58 |
Last Modified: | 25 Jun 2023 21:53 |
Status: | Published |
Publisher: | American Association for the Advancement of Science |
Identification Number: | 10.1126/sciadv.aax1803 |
Open Archives Initiative ID (OAI ID): | oai:eprints.whiterose.ac.uk:148062 |