Studies of copper(II)-binding to bacterioferritin and its effect on iron(II) oxidation

Baaghil, Suzanne, Thomson, Andrew J., Moore, Geoffrey R. and Le Brun, Nick E. (2002) Studies of copper(II)-binding to bacterioferritin and its effect on iron(II) oxidation. Dalton Transactions (5). pp. 811-818. ISSN 1477-9226

Full text not available from this repository.

Abstract

The iron-storage protein bacterioferritin (BFR) from Escherichia coli consists of twenty four identical subunits, each containing a dinuclear metal ion-binding site (the ferroxidase centre) at which iron(II) is oxidised to iron(III) and dioxygen is reduced. Other metal ions that are commonly found in biological systems bind to the ferroxidase centre, including manganese(II), cobalt(II) and zinc(II). In this work, copper(II)-binding to BFR and its effect on iron(II) oxidation kinetics were studied by a combination of gel filtration-copper(II) binding assay, optical, magnetic and kinetic methods. Data indicate that two copper(II) ions bind per subunit with a Kd of ≈ 2.0 × 10-5 M and establish the order of divalent metal ion binding as Cu(II) < Co(II) < Zn(II), i.e. it does not follow the Irving-Williams order. A number of lower affinity copper(II)-binding sites were also detected. The presence of copper(II) was found to significantly enhance the rate of iron(II) oxidation and subsequent core formation. This effect does not arise from copper(II) bound at the ferroxidase centre but, rather, is due to displaced copper(II). The nature of the displaced copper is discussed.

Item Type:	Article
Uncontrolled Keywords:	inorganic chemistry ,/dk/atira/pure/subjectarea/asjc/1600/1604
Faculty \ School:	Faculty of Science > School of Chemical Sciences and Pharmacy (former - to 2009) Faculty of Science > School of Chemistry (former - to 2024)
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:	http://www.scopus.com/inward/record.url?...
Depositing User:	LivePure Connector
Date Deposited:	18 Jun 2025 09:30
Last Modified:	18 Jun 2025 09:30
URI:	https://ueaeprints.uea.ac.uk/id/eprint/99602
DOI:	10.1039/b107288a

Actions (login required)

View Item