Iron binding and autoreduction by citrate: are these involved in signalling by iron regulatory protein-1?
Ferric ions bind to citrate and undergo an autoreduction to form a ferrous-citrate complex, greatly increasing the redox activity of the iron complex. Ferrous ions and citrate are also essential for the enzymic activity of aconitase. Aconitase, with its iron-sulphur cluster has a versatile structure which allows it to act as an iron regulatory protein (IRP-1). The purpose of this study was to see whether iron binding, and its autoreduction by citrate, could play a physiological signalling role in iron regulation. Significant amounts of ferrous ions were associated with citrate, when measured using ferrozine, however, these did not appear to activate iron-requiring aconitase.
Oxygen Chemistry Laboratory, Royal Brompton Hospital, London.
J M
JM
Gutteridge
S
S
Mumby
N J
NJ
Lamb
D000154:Aconitate Hydratase / Q000378:metabolism*; D000818:Animals; D002712:Chlorides; D019343:Citric Acid / Q000378:metabolism*; D005290:Ferric Compounds / Q000378:metabolism*; D035941:Iron Regulatory Protein 1; D035925:Iron-Regulatory Proteins; D007506:Iron-Sulfur Proteins / Q000378:metabolism*; D010084:Oxidation-Reduction; D016601:RNA-Binding Proteins / Q000378:metabolism*; D011990:Receptors, Transferrin / Q000378:metabolism
D002712:Chlorides; D005290:Ferric Compounds; D035925:Iron-Regulatory Proteins; D007506:Iron-Sulfur Proteins; D016601:RNA-Binding Proteins; D011990:Receptors, Transferrin; D019343:Citric Acid; D000154:Aconitate Hydratase; D035941:Iron Regulatory Protein 1; C024555:ferric chloride