title: Monoamine oxidase contains a redox-active disulfide.
abstract: Mitochondrial monoamine oxidases A and B (MAO A and MAO B) are ubiquitous homodimeric FAD-containing oxidases that catalyze the oxidation of biogenic amines. Both enzymes play a vital role in the regulation of neurotransmitter levels in brain and are of interest as drug targets. However, little is known about the amino acid residues involved in the catalysis. The experiments reported here show that both MAO A and MAO B contain a redox-active disulfide at the catalytic center. The results imply that MAO may be a novel type of disulfide oxidoreductase and open the way to characterizing the catalytic and chemical mechanism of the enzyme.
authors.affiliation: School of Biological and Medical Sciences, University of St. Andrews, Irvine Building, North Street, St. Andrews, KY16 9AL, Scotland, United Kingdom.
authors.forename: S O
authors.initials: SO
authors.lastname: Sablin
authors.forename: R R
authors.initials: RR
authors.lastname: Ramsay
mesh_terms: D000818:Animals; D001665:Binding Sites / Q000502:physiology; D002417:Cattle; D003913:Dextroamphetamine / Q000494:pharmacology; D004220:Disulfides / Q000737:chemistry* / Q000378:metabolism; D004227:Dithionite / Q000378:metabolism; D004579:Electron Transport / Q000502:physiology; D004791:Enzyme Inhibitors / Q000494:pharmacology; D005420:Flavoproteins / Q000737:chemistry; D006801:Humans; D008623:Mercaptoethanol / Q000378:metabolism; D008930:Mitochondria, Liver / Q000201:enzymology*; D008995:Monoamine Oxidase / Q000737:chemistry*; D010084:Oxidation-Reduction; D010088:Oxidoreductases / Q000737:chemistry; D011725:Pyridines / Q000378:metabolism; D013053:Spectrophotometry
chemical_list: D004220:Disulfides; D004791:Enzyme Inhibitors; D005420:Flavoproteins; D011725:Pyridines; D004227:Dithionite; C007542:4,4'-dipyridyl disulfide; D008623:Mercaptoethanol; D010088:Oxidoreductases; D008995:Monoamine Oxidase; D003913:Dextroamphetamine