Deferiprone (L1) induced conformation change of hemoglobin: A fluorescence and CD spectroscopic study

The interaction of deferiprone (1,2-dimethyl-3-hydroxy-pyrid-4-one) L1, the first clinically available oral iron chelator, with the tetrameric allosteric protein hemoglobin from human red blood cells has been investigated spectrofluorometrically and by circular dichroism spectroscopy. The interaction is hydrogenbond like electrostatic in nature, the binding constant being 4.54 x 10(3) M-1 in 0.15 M NaCl. Circular dichroism studies indicate a conformational change of hemoglobin in presence of deferiprone, helicity of hemoglobin being reduced in presence of increasing concentration of the drug L1.