Print Email Facebook Twitter Life on N2O: deciphering the ecophysiology of N2O respiring bacterial communities in a continuous culture Title Life on N2O: deciphering the ecophysiology of N2O respiring bacterial communities in a continuous culture Author Conthe Calvo, M. (TU Delft BT/Environmental Biotechnology) Wittorf, Lea (Swedish University of Agricultural Sciences) Kuenen, J.G. (TU Delft BT/Environmental Biotechnology) Kleerebezem, R. (TU Delft BT/Environmental Biotechnology) van Loosdrecht, Mark C.M. (TU Delft BT/Environmental Biotechnology) Hallin, Sara (Swedish University of Agricultural Sciences) Date 2018-02-07 Abstract Reduction of the greenhouse gas N2O to N2 is a trait among denitrifying and non-denitrifying microorganisms having an N2O reductase, encoded by nosZ. The nosZ phylogeny has two major clades, I and II, and physiological differences among organisms within the clades may affect N2O emissions from ecosystems. To increase our understanding of the ecophysiology of N2O reducers, we determined the thermodynamic growth efficiency of N2O reduction and the selection of N2O reducers under N2O- or acetate-limiting conditions in a continuous culture enriched from a natural community with N2O as electron acceptor and acetate as electron donor. The biomass yields were higher during N2O limitation, irrespective of dilution rate and community composition. The former was corroborated in a continuous culture of Pseudomonas stutzeri and was potentially due to cytotoxic effects of surplus N2O. Denitrifiers were favored over non-denitrifying N2O reducers under all conditions and Proteobacteria harboring clade I nosZ dominated. The abundance of nosZ clade II increased when allowing for lower growth rates, but bacteria with nosZ clade I had a higher affinity for N2O, as defined by μmax/Ks. Thus, the specific growth rate is likely a key factor determining the composition of communities living on N2O respiration under growth-limited conditions. To reference this document use: http://resolver.tudelft.nl/uuid:f8a9dbb5-4f2c-4d16-abba-1037f6789941 DOI https://doi.org/10.1038/s41396-018-0063-7 ISSN 1751-7362 Source The ISME Journal: multidisciplinary journal of microbial ecology, 12, 1-12 Part of collection Institutional Repository Document type journal article Rights © 2018 M. Conthe Calvo, Lea Wittorf, J.G. Kuenen, R. Kleerebezem, Mark C.M. van Loosdrecht, Sara Hallin Files PDF s41396_018_0063_7.pdf 1.88 MB Close viewer /islandora/object/uuid:f8a9dbb5-4f2c-4d16-abba-1037f6789941/datastream/OBJ/view