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Updated: Jun 24, 2026
08:23
Chemiluminescence-based Assays for Detection of Nitric Oxide and its Derivatives from Autoxidation and Nitrosated Compounds
Published on: February 16, 2022
The bacterial respiratory nitric oxide reductase
Nicholas J Watmough1, Sarah J Field, Ross J L Hughes
1Centre for Metalloprotein Spectroscopy and Biology, School of Biological Sciences, University of East Anglia, Norwich, UK. N.Watmough@uea.ac.uk
Biochemical Society Transactions
|March 18, 2009
Summary
Researchers studied the bacterial nitric oxide reductase (NOR), a key enzyme in denitrification. They propose a revised mechanism for how it converts nitric oxide to nitrous oxide, involving electron and proton transfer.
Area of Science:
- Biochemistry
- Microbiology
- Enzymology
Background:
- The bacterial nitric oxide reductase (NOR) is crucial for denitrification in soil bacteria.
- NOR belongs to the haem-copper oxidase superfamily but utilizes non-haem iron at its active site.
- It catalyzes the reduction of nitric oxide (NO) to nitrous oxide (N2O).
Purpose of the Study:
- To elucidate the electron and proton transfer pathways in the NorBC complex.
- To integrate mechanistic insights with substrate binding at the active site.
- To propose a revised, experimentally testable reaction mechanism for NOR.
Main Methods:
- Characterization of the two-subunit cytochrome bc complex (NorBC) from Paracoccus denitrificans.
- Analysis of electron and proton transfer pathways.
- Integration of substrate binding evidence.
Main Results:
- Detailed understanding of electron and proton transfer in NOR.
- Insights into substrate binding modes at the active site.
- A proposed revised reaction mechanism for NOR.
Conclusions:
- The study advances the understanding of bacterial nitric oxide reductase function.
- The proposed mechanism provides a framework for future experimental validation.
- This research contributes to the knowledge of microbial respiration and nitrogen cycling.
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