Articles | Volume 23, issue 18
https://doi.org/10.5194/bg-23-6705-2026
© Author(s) 2026. This work is distributed under
the Creative Commons Attribution 4.0 License.
the Creative Commons Attribution 4.0 License.
https://doi.org/10.5194/bg-23-6705-2026
© Author(s) 2026. This work is distributed under
the Creative Commons Attribution 4.0 License.
the Creative Commons Attribution 4.0 License.
Research article
| 
24 Sep 2026
Research article |
| 24 Sep 2026
| 24 Sep 2026
High nitrous oxide isotopic variability during denitrification by Pseudomonas species bearing NirK and NirS
Laboratory for Air Pollution/Environmental Technology, Empa, Überlandstrasse 129, Dübendorf, Switzerland
Aquatic and Isotope Biogeochemistry, University of Basel, Bernoullistrasse 30, Basel, Switzerland
Paul M. Magyar
Laboratory for Air Pollution/Environmental Technology, Empa, Überlandstrasse 129, Dübendorf, Switzerland
Jakob Zopfi
Aquatic and Isotope Biogeochemistry, University of Basel, Bernoullistrasse 30, Basel, Switzerland
Claudia Frey
Aquatic and Isotope Biogeochemistry, University of Basel, Bernoullistrasse 30, Basel, Switzerland
Thomas Kuhn
Aquatic and Isotope Biogeochemistry, University of Basel, Bernoullistrasse 30, Basel, Switzerland
Moritz F. Lehmann
Aquatic and Isotope Biogeochemistry, University of Basel, Bernoullistrasse 30, Basel, Switzerland
Laboratory for Air Pollution/Environmental Technology, Empa, Überlandstrasse 129, Dübendorf, Switzerland
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Short summary
N₂O is a greenhouse gas produced by microbes during nitrogen cycling. We studied two bacterial species and found that the isotope signatures of the N₂O they produced changed strongly depending on growth conditions and cell activity. Early during growth, the distribution of N isotopes within the N₂O molecule also changed unexpectedly. These results show that N₂O isotope signatures are more variable than previously assumed and depend strongly on physiology.
N₂O is a greenhouse gas produced by microbes during nitrogen cycling. We studied two bacterial...
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