title: Compelling EPR evidence that the alternative oxidase is a diiron carboxylate protein.
abstract: The alternative oxidase is a respiratory chain protein found in plants, fungi and some parasites that still remains physically uncharacterised. In this report we present EPR evidence from parallel mode experiments which reveal signals at approximately g=16 in both purified alternative oxidase protein (g=16.9), isolated mitochondrial membranes (g=16.1), and in trypanosomal AOX expressed in Escherichia coli membranes (g=16.4). Such signals are indicative of a dicarboxylate diiron centre at the active site of the enzyme. To our knowledge these data represent the first EPR signals from AOX present in its native environment.
authors.affiliation: Department of Biochemistry, School of Life Sciences, University of Sussex, Falmer Brighton BN1 9QG UK. a.l.moore@sussex.ac.uk
authors.forename: Anthony L
authors.initials: AL
authors.lastname: Moore
authors.forename: Jane E
authors.initials: JE
authors.lastname: Carré
authors.forename: Charles
authors.initials: C
authors.lastname: Affourtit
authors.forename: Mary S
authors.initials: MS
authors.lastname: Albury
authors.forename: Paul G
authors.initials: PG
authors.lastname: Crichton
authors.forename: Kiyoshi
authors.initials: K
authors.lastname: Kita
authors.forename: Peter
authors.initials: P
authors.lastname: Heathcote
mesh_terms: D000818:Animals; D001665:Binding Sites; D004578:Electron Spin Resonance Spectroscopy; D004579:Electron Transport; D007501:Iron / Q000737:chemistry*; D051336:Mitochondrial Membranes / Q000737:chemistry / Q000201:enzymology; D024101:Mitochondrial Proteins; D010088:Oxidoreductases / Q000737:chemistry*; D010940:Plant Proteins; D014345:Trypanosoma / Q000201:enzymology; D000099188:Alternative Oxidase
chemical_list: D007501:Iron; D024101:Mitochondrial Proteins; D010088:Oxidoreductases; D010940:Plant Proteins; D000099188:Alternative Oxidase