Bennett, Sophie, Torres, Maria, Soriano-Laguna, Manuel, Richardson, David ORCID: https://orcid.org/0000-0002-6847-1832, Gates, Andrew J
ORCID: https://orcid.org/0000-0002-4594-5038 and Le Brun, Nick
ORCID: https://orcid.org/0000-0001-9780-4061
(2020)
nosX is essential for whole cell N2O reduction in Paracoccus denitrificans but not for assembly of copper centres of nitrous oxide reductase.
Microbiology, 166 (10).
909–917.
ISSN 1350-0872
Preview |
PDF (NosX manuscript_Microbiol_revised_marked_final)
- Accepted Version
Download (804kB) | Preview |
Preview |
PDF (Published_Version)
- Published Version
Available under License Creative Commons Attribution. Download (1MB) | Preview |
Abstract
Nitrous oxide (N2O) is a potent greenhouse gas that is produced naturally as an intermediate during the process of denitrification carried out by some soil bacteria. It is consumed by nitrous oxide reductase (N2OR), the terminal enzyme of the denitrification pathway, which catalyses a reduction reaction to generate dinitrogen. N2OR contains two important copper cofactors (CuA and CuZ centres) that are essential for activity, and in copper-limited environments, N2OR fails to function, contributing to rising levels of atmospheric N2O and a major environmental challenge. Here we report studies of nosX, one of eight genes in the nos cluster of the soil dwelling α-proteobaterium Paraccocus denitrificans. A P. denitrificans ΔnosX deletion mutant failed to reduce N2O under both copper-sufficient and copper-limited conditions, demonstrating that NosX plays an essential role in N2OR activity. N2OR isolated from nosX-deficient cells was found to be unaffected in terms of the assembly of its copper cofactors, and to be active in in vitro assays, indicating that NosX is not required for the maturation of the enzyme; in particular, it plays no part in the assembly of either of the CuA and CuZ centres. Furthermore, quantitative Reverse Transcription PCR (qRT-PCR) studies showed that NosX does not significantly affect the expression of the N2OR-encoding nosZ gene. NosX is a homologue of the FAD-binding protein ApbE from Pseudomonas stutzeri, which functions in the flavinylation of another N2OR accessory protein, NosR. Thus, it is likely that NosX is a system-specific maturation factor of NosR, and so is indirectly involved in maintaining the reaction cycle of N2OR and cellular N2O reduction.
Item Type: | Article |
---|---|
Uncontrolled Keywords: | copper,denitrification,nitrous oxide,nitrous oxide reductase,microbiology ,/dk/atira/pure/subjectarea/asjc/2400/2404 |
Faculty \ School: | Faculty of Science > School of Chemistry Faculty of Science > School of Biological Sciences |
UEA Research Groups: | Faculty of Science > Research Groups > Organisms and the Environment Faculty of Science > Research Groups > Molecular Microbiology Faculty of Science > Research Centres > Centre for Molecular and Structural Biochemistry Faculty of Science > Research Groups > Chemistry of Life Processes |
Related URLs: | |
Depositing User: | LivePure Connector |
Date Deposited: | 22 Jul 2020 02:46 |
Last Modified: | 14 May 2023 00:31 |
URI: | https://ueaeprints.uea.ac.uk/id/eprint/76219 |
DOI: | 10.1099/mic.0.000955 |
Downloads
Downloads per month over past year
Actions (login required)
![]() |
View Item |