Nitrous-oxide reductase
| nitrous oxide reductase | |||||||||
|---|---|---|---|---|---|---|---|---|---|
ExPASy NiceZyme view | | ||||||||
| KEGG | KEGG entry | ||||||||
| MetaCyc | metabolic pathway | ||||||||
| PRIAM | profile | ||||||||
| PDB structures | RCSB PDB PDBe PDBsum | ||||||||
| Gene Ontology | AmiGO / QuickGO | ||||||||
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In
- N2O + 2 reduced cytochome c ⇌ N2 + H2O + 2 cytochrome c
It plays a critical role in preventing release of a potent greenhouse gas into the atmosphere.
Function
N2O is an inorganic metabolite of the
fungi. Among them, only denitrifying prokaryotes have the ability to convert N2O to N2.[3] Conversion of N2O into N2 is the last step of a complete nitrate denitrification process and is an autonomous form of respiration. N2O is generated in the denitrifying cell by the activity of respiratory NO reductase.[4] Some microbial communities only have the capability of N2O reduction to N2 and do not possess the other denitrification pathways. Such communities are known as nitrous oxide reducers.[5] Some denitrifiers do not have complete denitrification with end product N2O[6]
Structure
Nitrous-oxide reductase is a
copper protein
known as CuA.
The second domain comprises a 7-bladed
cluster.[8] The distance between the CuA and CuZ centers within a single subunit is greater than 30Å, a distance that precludes physiologically relevant rates of intra-subunit electron transfer. However, the two subunits are orientated "head to tail" such that the CuA center in one subunit lies only 10 Å from the CuZ center in the second ensuring that pairs of redox centers in opposite subunits form the catalytically competent unit.[9] The CuA center can undergo a one-electron redox change and hence has a function similar to that in the well-known aa3-type cytochrome c oxidases (EC 1.9.3.1) where it serves to receive an electron from soluble cytochromes c.[10]
Inhibitors
Acetylene is the most specific inhibitor of nitrous-oxide reductase.[11] Other inhibitors include azide anion,[12] thiocyanate, carbon monoxide, iodide, and cyanide.[13]
References
- ^
Schneider, Lisa K.; Wüst, Anja; Pomowski, Anja; Zhang, Lin; Einsle, Oliver (2014). "Chapter 8. No Laughing Matter: The Unmaking of the Greenhouse Gas Dinitrogen Monoxide by Nitrous Oxide Reductase". In Peter M.H. Kroneck and Martha E. Sosa Torres (ed.). The Metal-Driven Biogeochemistry of Gaseous Compounds in the Environment. Metal Ions in Life Sciences. Vol. 14. Springer. pp. 177–210. PMID 25416395.
- PMID 8534676.
- ISBN 978-0-444-52857-5.
- PMID 15598502.
- PMID 26441904.
- hdl:10919/48086.
- PMID 12356332.
- PMID 16234931.
- S2CID 45975377.
- PMID 1267447.
- PMID 5718551.
- PMID 7356639.
