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ToolsYang, Xiaoke, Le Brun, Nick E., Thomson, Andrew J., Moore, Geoffrey R. and Chasteen, N. Dennis (2000) The iron oxidation and hydrolysis chemistry of Escherichia coli bacterioferritin. Biochemistry, 39 (16). pp. 4915-4923. ISSN 0006-2960
Full text not available from this repository.Abstract
Bacterioferritins are members of a class of spherical shell-like iron storage proteins that catalyze the oxidation and hydrolysis of iron at specific sites inside the protein shell, resulting in formation of a mineral core of hydrated ferric oxide within the protein cavity. Electrode oximetry/pH stat was used to study iron oxidation and hydrolysis chemistry in E. coli bacterioferritin. Consistent with previous UV-visible absorbance measurements, three distinct kinetic phases were detected, and the stoichiometric equations corresponding to each have been determined. The rapid phase 1 reaction corresponds to pairwise binding of 2 Fe2+ ions at a dinuclear site, called the ferroxidase site, located within each of the 24 subunits, viz., 2Fe2+ + P(z) → [Fe2-P](z) + 4H+, where P(z) is the apoprotein of net charge Z and [Fe2-P](z) represents a diferrous ferroxidase complex. The slower phase 2 reaction corresponds to the oxidation of this complex by molecular oxygen according to the net equation: [Fe2-P](z) + 1/2 O2 → [Fe2O-P](z) where [Fe2O-P](z) represents an oxidized diferric ferroxidase complex, probably a μ-oxo-bridged species as suggested by UV- visible and EPR spectrometric titration data. The third phase corresponds to mineral core formation according to the net reaction: 4Fe2+ + O2 + 6H2O → 4FeO(OH)((core)) + 8H+. Iron oxidation is inhibited by the presence of Zn2+ ions. The patterns of phase 2 and phase 3 inhibition are different, though inhibition of both phases is complete at 48 Zn2+per 24mer, i.e., 2 Zn2+ per ferroxidase center.
| Item Type: | Article |
|---|---|
| Uncontrolled Keywords: | biochemistry ,/dk/atira/pure/subjectarea/asjc/1300/1303 |
| Faculty \ School: | Faculty of Science > School of Chemistry (former - to 2024) Faculty of Science > School of Chemical Sciences and Pharmacy (former - to 2009) |
| UEA Research Groups: | Faculty of Science > Research Centres > Centre for Molecular and Structural Biochemistry Faculty of Science > Research Groups > Chemistry of Life Processes |
| Related URLs: | |
| Depositing User: | LivePure Connector |
| Date Deposited: | 18 Jun 2025 09:30 |
| Last Modified: | 18 Jun 2025 11:30 |
| URI: | https://ueaeprints.uea.ac.uk/id/eprint/99605 |
| DOI: | 10.1021/bi992631f |
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