Encyclopedia of Metalloproteins

2013 Edition
| Editors: Robert H. Kretsinger, Vladimir N. Uversky, Eugene A. Permyakov

Bismuth, Interaction with Transferrin

  • Graham S. Baldwin
Reference work entry
DOI: https://doi.org/10.1007/978-1-4614-1533-6_200005

Definition

Transferrin is an abundant serum glycoprotein of molecular mass 80 kDa (kilodaltons) (Wally and Buchanan 2007). Sequence similarity between the N- and C-terminal lobes of the molecule indicates that transferrin has evolved by duplication of an ancestral gene. Each lobe binds a single ferric ion with high affinity, via the side chains of two tyrosines, a histidine, and an aspartic acid. The remaining two ligands in the distorted octahedral binding site are provided by the synergistic anion bicarbonate. Transferrin is responsible for the transport of iron around the body, and delivers iron to target cells via interaction with the transferrin receptor TfR1. A related protein, lactoferrin, is found in milk and other secreted fluids, where its ability to bind iron tightly limits bacterial growth.

Basic Characteristics

Binding of Bismuth by Transferrins

In the presence of bicarbonate, bismuth ions bind to both ferric ion–binding sites of transferrin (Li et al. 1996; Sun et al. 1999...

This is a preview of subscription content, log in to check access.

References

  1. Li H, Sadler PJ, Sun H (1996) Unexpectedly strong binding of a large metal ion (Bi3+) to human serum transferrin. J Biol Chem 271:9483–9489PubMedCrossRefGoogle Scholar
  2. Miquel G, Nekaa T, Kahn PH et al (2004) Mechanism of formation of the complex between transferrin and bismuth, and interaction with transferrin receptor 1. Biochemistry 43:14722–14731PubMedCrossRefGoogle Scholar
  3. Sun H, Li H, Mason AB et al (1999) N-lobe versus C-lobe complexation of bismuth by human transferrin. Biochem J 337(Pt 1):105–111PubMedCrossRefGoogle Scholar
  4. Sun H, Li H, Mason AB et al (2001) Competitive binding of bismuth to transferrin and albumin in aqueous solution and in blood plasma. J Biol Chem 276:8829–8835PubMedCrossRefGoogle Scholar
  5. Wally J, Buchanan SK (2007) A structural comparison of human serum transferrin and human lactoferrin. Biometals 20:249–262PubMedCrossRefGoogle Scholar
  6. Zhang L, Szeto KY, Wong WB et al (2001) Interactions of bismuth with human lactoferrin and recognition of the Bi(III)-lactoferrin complex by intestinal cells. Biochemistry 40:13281–13287PubMedCrossRefGoogle Scholar

Copyright information

© Springer Science+Business Media New York 2013

Authors and Affiliations

  1. 1.Department of Surgery, Austin HealthThe University of MelbourneHeidelbergAustralia