title: Abduction of iron(III) from the soluble methane monooxygenase hydroxylase and reconstitution of the binuclear site with iron and manganese.
abstract: The apo-form of the soluble methane monooxygenase hydroxylase from Methylococcus capsulatus (Bath) was prepared via chelation of iron(III) with 3,4-dihydroxybenzaldehyde. The apohydroxylase was reconstituted by the anaerobic addition of Fe(II) followed by air oxidation. The enzyme thus prepared regained 85-90% of its original catalytic activity. The incorporation of two manganese(II) ions/mol of apohydroxylase was monitored by EPR spectroscopy. The Mn(II) ions occupy the native diiron active site and remain in the +2 oxidation state. The EPR data suggest strong coupling between the two Mn(II) ions and retention of the mu-hydroxo (alkoxo) bridge. The results of this study indicate that the M. capsulatus (Bath) hydroxylase contains a single diiron site.
authors.affiliation: Laboratoire d'Etudes Dynamiques et Structurales de la Selectivite, URA Centre National de la Recherche Scientifique 0332, Universite J. Fourier, Grenoble, France.
authors.forename: M
authors.initials: M
authors.lastname: Atta
authors.forename: M
authors.initials: M
authors.lastname: Fontecave
authors.forename: P C
authors.initials: PC
authors.lastname: Wilkins
authors.forename: H
authors.initials: H
authors.lastname: Dalton
mesh_terms: D001051:Apoenzymes / Q000737:chemistry / Q000378:metabolism; D001386:Azides / Q000494:pharmacology; D001547:Benzaldehydes; D001665:Binding Sites; D002384:Catalysis; D002396:Catechols; D002614:Chelating Agents; D004578:Electron Spin Resonance Spectroscopy; D005290:Ferric Compounds / Q000737:chemistry*; D005296:Ferrous Compounds / Q000737:chemistry*; D008345:Manganese / Q000737:chemistry*; D008772:Methylococcaceae / Q000201:enzymology; D006899:Mixed Function Oxygenases / Q000737:chemistry / Q000378:metabolism; D010084:Oxidation-Reduction; D010105:Oxygenases / Q000737:chemistry* / Q000378:metabolism; D013329:Structure-Activity Relationship
chemical_list: D001051:Apoenzymes; D001386:Azides; D001547:Benzaldehydes; D002396:Catechols; D002614:Chelating Agents; D005290:Ferric Compounds; D005296:Ferrous Compounds; D008345:Manganese; C005581:protocatechualdehyde; D006899:Mixed Function Oxygenases; D010105:Oxygenases; C021555:methane monooxygenase