See for example:
“The Influence of the
Synergistic Anion on Iron Chelation by Ferric Binding Protein, A
Bacterial Transferrin” S. Dhungana, C. H. Taboy, D. S. Anderson,
K. G. Vaughan, P. Aisen, T. A. Mietzner, and A. L Crumbliss,
Proc. Natl. Acad. Sci. (USA), 100, 3659 (2003).
“Kinetics and Mechanism of
Iron(III) Complexation by Ferric Binding Protein: The Role of
Phosphate” M. Gabričević, D. S. Anderson, T. A.
Mietzner, and A. L. Crumbliss, Biochemistry, 43,
5811 (2004).