The Binding of Scandium Ions to Transferrin in vivo and in vitro

Abstract

Studies on the binding of scandium to human apotransferrin showed that two Sc3+ were bound specifically at the two iron‐binding sites. The binding of each Sc3+ involves the ionisation of two phenolic tyrosyl residues. The scandium · protein complex has similar resistance to denaturants and chemical reagents as the iron complex. The only protein complex observed, when quantities of Sc3+ below the free iron binding capacity of serum were added to whole serum in vitro, was the Sc3+· transferrin complex. The injection of Sc3+, as a 1:2 citrate complex, into rabbits led after 48 h to all the plasma Sc3+ being present as the transferrin complex. Copyright © 1971, Wiley Blackwell. All rights reserved