Human transferrin is a blood plasma protein for iron ion delivery encoded by the TF gene. The gene coding for transferrin in humans is located in chromosome band 3q21. Transferrin is a glycoprotein, which binds iron very tightly but reversibly. Transferrin contains 2 specific high-affinity Fe(III) binding sites. The affinity of transferrin for Fe(III) is extremely high (1023 M-1 at pH 7.4) but decreases progressively with decreasing pH below neutrality. The metal binding properties of transferrin have a great influence on the biochemistry of plutonium.
Background References
1. McGillivray R.T.A., Mendez E., Sinha S.K., Sutton M.R., Lineback-Zins J., Brew K.; "The complete amino acid sequence of human serum transferrin."; Proc. Natl. Acad. Sci. U.S.A. 79:2504-2508(1982).
2. McGillivray R.T.A., Mendez E., Shewale J.G., Sinha S.K., Lineback-Zins J., Brew K.; "The primary structure of human serum transferrin. The structures of seven cyanogen bromide fragments and the assembly of the complete structure."; J. Biol. Chem. 258:3543-3553(1983).