Download MendeleyNitrous oxide production via enzymatic nitroxyl from the nitrifying archaeon Nitrosopumilus maritimus.
Voland, R.W., Wang, H., Abruna, H.D., Lancaster, K.M.(2025) Proc Natl Acad Sci U S A 122: e2416971122-e2416971122
- PubMed: 39823305
- DOI: https://doi.org/10.1073/pnas.2416971122
- Primary Citation of Related Structures:
9CCK - PubMed Abstract:
Ammonia oxidizing archaea (AOA) are among the most abundant microorganisms on earth and are known to be a major source of nitrous oxide (N 2 O) emissions, although biochemical origins of this N 2 O remain unknown. Enzymological details of AOA nitrogen metabolism are broadly unavailable. We report the recombinant expression, purification, and characterization of a multicopper oxidase, Nmar_1354, from the AOA Nitrosopumilus maritimus . We show that Nmar_1354 selectively produces nitroxyl (HNO) by coupling the oxidation of the obligate nitrification intermediate hydroxylamine (NH 2 OH) to dioxygen (O 2 ) reduction. This HNO undergoes several downstream reactions, although the major fates are production of N 2 via reaction with NH 2 OH and dimerization with itself to yield N 2 O. These results afford one plausible enzymatic origin for N 2 O release by AOA. Moreover, these results reveal a physiologically relevant enzymatic reaction for producing HNO, an enigmatic nitrogen oxide speculated to be operative in cellular signaling and in energy transduction.
- Department of Chemistry and Chemical Biology, Baker Laboratory, Cornell University, Ithaca, NY 14853.
Organizational Affiliation:
