Pathway of nitrous oxide consumption in isolated Pseudomonas stutzeri strains under anoxic and oxic conditions. (18th February 2014)

• Record Type: Journal Article
• Authors: Desloover, Joachim; Roobroeck, Dries; Heylen, Kim; Puig, Sebastià; Boeckx, Pascal; Verstraete, Willy; Boon, Nico
• Is Part Of: Environmental microbiology. Volume 16:Number 10(2014:Oct.)
• Page Start: 3143
• Page End: 3152
• Publication Date: 2014-02-18
• Subjects: Microbial ecology -- Periodicals; Environmental Microbiology -- Periodicals; 579.17
• DOI: 10.1111/1462-2920.12404
• Languages: English
• ISSNs: 1462-2912

Abstract

<abstract abstract-type="main"> <title>Summary</title> <p>The microbial consumption of nitrous oxide (N₂O) has gained great interest since it was revealed that this process could mitigate the greenhouse effect of N₂O. The consumption of N₂O results from its reduction to dinitrogen gas (N₂) as part of the denitrification process. However, there is ongoing debate regarding an alternative pathway, namely reduction of N₂O to NH₄⁺, or assimilatory N₂O consumption. To date, this pathway is poorly investigated and lacks unambiguous evidence. Enrichment of denitrifying activated sludge using a mineral nitrogen‐free medium rendered a mixed culture capable of anoxic and oxic N₂O consumption. Dilution plating, isolation and deoxyribonucleic acid fingerprinting identified a collection of <italic>P</italic><italic>seudomonas stutzeri</italic> strains as dominant N₂O consumers in both anaerobic and aerobic enrichments. A detailed isotope tracing experiment with a <italic>P</italic><italic>seudomonas stutzeri</italic> isolate showed that consumption of N₂O via assimilatory reduction to NH₄⁺ was absent. Conversely, respiratory N₂O reduction was directly coupled to N₂ fixation.</p> </abstract>