title: Computational study of iron(II) and -(III) complexes with a simple model human H ferritin ferroxidase center.
abstract: Interaction of iron ions with a six-amino acid model of the ferroxidase center of human H chain ferritin has been examined in density functional theory calculations. The model, based on experimental studies of oxidation of Fe2+ at the center, consists of Glu27, Glu62, His65, Glu107, Gln141, and Ala144. Reasonable structures are obtained in a survey of types of iron complexes inferred to occur in the ferroxidase reaction. Structures of complexes of the model center with one and two Fe2+ ions, with diiron(III) bridged by peroxide and bridged by oxide-peroxide combinations, have been optimized. Calculations on diiron(III) complexes confirm that stable peroxide-bridged complexes can form and that the Fe-Fe distance in at least one is consistent with the experimental Fe-Fe distance observed in the blue peroxodiferric complex of ferritin.
authors.affiliation: Department of Sciences and Technology, Universidad Metropolitana, San Juan, Puerto Rico 00928-1150.
authors.forename: Daniel E
authors.initials: DE
authors.lastname: Bacelo
authors.forename: R C
authors.initials: RC
authors.lastname: Binning
mesh_terms: D000409:Alanine / Q000737:chemistry; D002570:Ceruloplasmin / Q000737:chemistry* / Q000378:metabolism; D019295:Computational Biology; D005290:Ferric Compounds / Q000737:chemistry*; D005293:Ferritins / Q000737:chemistry* / Q000378:metabolism; D005296:Ferrous Compounds / Q000737:chemistry*; D018698:Glutamic Acid / Q000737:chemistry; D005973:Glutamine / Q000737:chemistry; D006801:Humans; D008958:Models, Molecular; D010545:Peroxides / Q000737:chemistry
chemical_list: D005290:Ferric Compounds; D005296:Ferrous Compounds; D010545:Peroxides; D005973:Glutamine; D018698:Glutamic Acid; D005293:Ferritins; D002570:Ceruloplasmin; D000409:Alanine