Growth of complete ammonia oxidizers on guanidine

Author(s)
Marton Palatinszky, Craig W Herbold, Christopher J Sedlacek, Dominic Pühringer, Katharina Kitzinger, Andrew T Giguere, Kenneth Wasmund, Per H Nielsen, Morten K D Dueholm, Nico Jehmlich, Richard Gruseck, Anton Legin, Julius Kostan, Nesrete Krasnici, Claudia Schreiner, Johanna Palmetzhofer, Thilo Hofmann, Michael Zumstein, Kristina Djinović-Carugo, Holger Daims, Michael Wagner
Abstract

Guanidine is a chemically stable nitrogen compound that is excreted in human urine and is widely used in manufacturing of plastics, as a flame retardant and as a component of propellants, and is well known as a protein denaturant in biochemistry1-3. Guanidine occurs widely in nature and is used by several microorganisms as a nitrogen source, but microorganisms growing on guanidine as the only substrate have not yet been identified. Here we show that the complete ammonia oxidizer (comammox) Nitrospira inopinata and probably most other comammox microorganisms can grow on guanidine as the sole source of energy, reductant and nitrogen. Proteomics, enzyme kinetics and the crystal structure of a N. inopinata guanidinase homologue demonstrated that it is a bona fide guanidinase. Incubation experiments with comammox-containing agricultural soil and wastewater treatment plant microbiomes suggested that guanidine serves as substrate for nitrification in the environment. The identification of guanidine as a growth substrate for comammox shows an unexpected niche of these globally important nitrifiers and offers opportunities for their isolation.

Organisation(s)
Department of Microbiology and Ecosystem Science, Department of Structural and Computational Biology, Centre for Microbiology and Environmental Systems Science, Department of Inorganic Chemistry, Department of Environmental Geosciences, The Comammox Research Platform
External organisation(s)
Max F. Perutz Laboratories GmbH (MFPL), Aalborg University (AAU), Helmholtz-Zentrum für Umweltforschung, Doctoral School in Microbiology and Environmental Science, University of Canterbury, European Molecular Biology Laboratory, University of Portsmouth
Journal
Nature
Volume
633
Pages
646-653
No. of pages
8
ISSN
0028-0836
DOI
https://doi.org/10.1038/s41586-024-07832-z
Publication date
2024
Peer reviewed
Yes
Austrian Fields of Science 2012
105205 Climate change, 106026 Ecosystem research, 106022 Microbiology
Keywords
ASJC Scopus subject areas
General
Sustainable Development Goals
SDG 13 - Climate Action
Portal url
https://ucrisportal.univie.ac.at/en/publications/1123b56d-d8e0-4362-b880-fbc2d79f21ae