Kinetic and structural characterization of an intermediate in the biomineralization of bacterioferritin.
The mechanism by which iron-storage proteins take up and oxidise iron(II) is not understood. We show by rapid-kinetic and EPR measurements that iron uptake, in vitro, by a bacterial iron-storage protein, bacterioferritin, involves at least three kinetically distinguishable phases: phase 1, the binding of Fe(II) ions, probably at a dimeric iron ferroxidase centre; phase 2, oxidation of the Fe(II) dimer and production of mononuclear Fe(III); and phase 3, iron core formation.
Le Brun
N E
NE
Centre for Metalloprotein Spectroscopy and Biology, School of Chemical Sciences, University of East Anglia, Norwich, UK.
Wilson
M T
MT
Andrews
S C
SC
Guest
J R
JR
Harrison
P M
PM
Thomson
A J
AJ
Moore
G R
GR
D001426:Bacterial Proteins / Q000737:chemistry / Q000378:metabolism; D003573:Cytochrome b Group / Q000737:chemistry / Q000378:metabolism*; D004578:Electron Spin Resonance Spectroscopy; D004926:Escherichia coli; D005293:Ferritins / Q000737:chemistry / Q000378:metabolism*; D007501:Iron / Q000378:metabolism; D007700:Kinetics
D001426:Bacterial Proteins; D003573:Cytochrome b Group; D005293:Ferritins; C018032:bacterioferritin; D007501:Iron