TY - JOUR
T1 - Growth of complete ammonia oxidizers on guanidine
AU - Palatinszky, Marton
AU - Herbold, Craig W
AU - Sedlacek, Christopher J
AU - Pühringer, Dominic
AU - Kitzinger, Katharina
AU - Giguere, Andrew T
AU - Wasmund, Kenneth
AU - Nielsen, Per H
AU - Dueholm, Morten K D
AU - Jehmlich, Nico
AU - Gruseck, Richard
AU - Legin, Anton
AU - Kostan, Julius
AU - Krasnici, Nesrete
AU - Schreiner, Claudia
AU - Palmetzhofer, Johanna
AU - Hofmann, Thilo
AU - Zumstein, Michael
AU - Djinović-Carugo, Kristina
AU - Daims, Holger
AU - Wagner, Michael
N1 - © 2024. The Author(s).
PY - 2024/9/19
Y1 - 2024/9/19
N2 - 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.
AB - 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.
KW - microbiology
KW - Structural Biology
KW - ammonia oxidizer
KW - guanidine
KW - comammox microorganisms
KW - Complete Ammonia Oxidizer
KW - Nitrospira inopinata
UR - http://www.scopus.com/inward/record.url?scp=85201304560&partnerID=8YFLogxK
U2 - 10.1038/s41586-024-07832-z
DO - 10.1038/s41586-024-07832-z
M3 - Article
C2 - 39143220
VL - 633
SP - 646
EP - 653
JO - Nature
JF - Nature
SN - 0028-0836
ER -