Site specificity of iron removal from transferrin by α-ketohydroxypyridine chelators

• Published in: FEBS letters 1985-09, Vol.189 (1), p.141-144
• Main Authors: Kontoghiorghes, George J., Evans, Robert W.
• Format: Article
• Language: English
• Subjects: 1,2-dimethyl-3-hydroxypyrid-4-one; Analytical, structural and metabolic biochemistry; Biological and medical sciences; Deferiprone; EDTP, ethylenediamine-N,N'-tetra(methylenephosphonic acid); Electrophoresis, Polyacrylamide Gel; Fe-Tf, N-terminal monoferric transferrin; Fe2-Tf, diferric transferrin; FeNTA, iron(III) nitrilotriacetate; Fundamental and applied biological sciences. Psychology; HEDP, 1-hydroxyethane-1,1-diphosphonic acid; Humans; Iron - metabolism; LICAMS, 1,5,10,N', N''-tris(5-sulfo-2,3-dihydroxybenzoyl)triazadecane; man; MECAM, 1,3,5-N,N',N''-tris(2,3-dihydroxybenzoyl)-aminomethylbenzene; Metalloproteins; mimosine; Mimosine - pharmacology; NTA, nitrilotriacetate; NTP, nitrilotri-(methylenephosphonic acid); Other metalloproteins; Proteins; Pyridones - pharmacology; Tf, transferrin; Tf-Fe, C-terminal monoferric transferrin; Time Factors; transferrin; Transferrin - metabolism
• ISSN: 0014-5793; 1873-3468
• DOI: 10.1016/0014-5793(85)80859-0

The site specificity of the removal of iron from diferric human transferrin, at pH 7.4, by two α-ketohydroxypyridine chelators, 1,2-dimethyl-3-hydroxypyrid-4-one (L 1) and mimosine, has been investigated using urea-polyacrylamide gel electrophoresis. Chelator L 1 removes iron preferentially from the C-terminal site whereas mimosine shows a small preference for iron in the N-terminal site. The removal of iron has also been followed spectrophotometrically and by monitoring the loss of 59Fe from [ 59Fe]transferrin. Both chelators are able to remove iron completely from diferric transferrin without additional mediators or reducing agents. Transferrin Iron mobilisation Site specificity α-Ketohydroxypyridine chelators Mimosine