title: Primary Amine Oxidase of Escherichia coli Is a Metabolic Enzyme that Can Use a Human Leukocyte Molecule as a Substrate.
abstract: Escherichia coli amine oxidase (ECAO), encoded by the tynA gene, catalyzes the oxidative deamination of aromatic amines into aldehydes through a well-established mechanism, but its exact biological role is unknown. We investigated the role of ECAO by screening environmental and human isolates for tynA and characterizing a tynA-deletion strain using microarray analysis and biochemical studies. The presence of tynA did not correlate with pathogenicity. In tynA+ Escherichia coli strains, ECAO enabled bacterial growth in phenylethylamine, and the resultant H2O2 was released into the growth medium. Some aminoglycoside antibiotics inhibited the enzymatic activity of ECAO, which could affect the growth of tynA+ bacteria. Our results suggest that tynA is a reserve gene used under stringent environmental conditions in which ECAO may, due to its production of H2O2, provide a growth advantage over other bacteria that are unable to manage high levels of this oxidant. In addition, ECAO, which resembles the human homolog hAOC3, is able to process an unknown substrate on human leukocytes.
authors.affiliation: MediCity Research Laboratory, University of Turku, Turku, Finland.|Department of Medical Microbiology and Immunology, University of Turku, Turku, Finland.
authors.forename: Heli
authors.initials: H
authors.lastname: Elovaara
authors.affiliation: MediCity Research Laboratory, University of Turku, Turku, Finland.|Department of Medical Microbiology and Immunology, University of Turku, Turku, Finland.|Turku Graduate School of Biomedical Sciences, Turku, Finland.
authors.forename: Teija
authors.initials: T
authors.lastname: Huusko
authors.affiliation: MediCity Research Laboratory, University of Turku, Turku, Finland.
authors.forename: Mikael
authors.initials: M
authors.lastname: Maksimow
authors.affiliation: MediCity Research Laboratory, University of Turku, Turku, Finland.|Department of Medical Biochemistry and Genetics, University of Turku, Turku, Finland.
authors.forename: Kati
authors.initials: K
authors.lastname: Elima
authors.affiliation: MediCity Research Laboratory, University of Turku, Turku, Finland.|Department of Medical Microbiology and Immunology, University of Turku, Turku, Finland.
authors.forename: Gennady G
authors.initials: GG
authors.lastname: Yegutkin
authors.affiliation: Department of Bacteriology and Immunology, Medicum, Immunobiology, Research Programs Unit, University of Helsinki, Helsinki, Finland and Helsinki University Central Hospital Laboratory Diagnostics, Helsinki, Finland.
authors.forename: Mikael
authors.initials: M
authors.lastname: Skurnik
authors.affiliation: Institute of Hygiene, University of Münster, Münster, Germany.
authors.forename: Ulrich
authors.initials: U
authors.lastname: Dobrindt
authors.affiliation: Bacteriology Unit, Department for Infectious Disease Surveillance and Control, National Institute for Health and Welfare, Helsinki, Finland.
authors.forename: Anja
authors.initials: A
authors.lastname: Siitonen
authors.affiliation: Astbury Centre for Structural Molecular Biology, Institute of Molecular and Cellular Biology, Faculty of Biological Sciences, University of Leeds, Leeds, United Kingdom.
authors.forename: Michael J
authors.initials: MJ
authors.lastname: McPherson
authors.affiliation: MediCity Research Laboratory, University of Turku, Turku, Finland.|Department of Medical Microbiology and Immunology, University of Turku, Turku, Finland.
authors.forename: Marko
authors.initials: M
authors.lastname: Salmi
authors.affiliation: MediCity Research Laboratory, University of Turku, Turku, Finland.|Department of Medical Microbiology and Immunology, University of Turku, Turku, Finland.
authors.forename: Sirpa
authors.initials: S
authors.lastname: Jalkanen
mesh_terms: D001665:Binding Sites; D004926:Escherichia coli / Q000201:enzymology*; D029968:Escherichia coli Proteins / Q000235:genetics / Q000378:metabolism*; D006801:Humans; D006861:Hydrogen Peroxide / Q000378:metabolism; D007962:Leukocytes / Q000378:metabolism*; D008995:Monoamine Oxidase / Q000235:genetics / Q000378:metabolism*; D030781:Organisms, Genetically Modified; D010084:Oxidation-Reduction
chemical_list: D029968:Escherichia coli Proteins; D006861:Hydrogen Peroxide; D008995:Monoamine Oxidase; C585158:TynA protein, E coli