Manganese and Iron Binding to Human Transferrin

The characteristics of manganese and iron binding to human apotransferrin (apo-tf) have been investigated and compared in this study. both metal ions were taken up by human apo-tf and formed complexes, with the maximum absorbances observed at 410 and 340 nm for manganese-transferrin (mn-tf) and 465 nm for iron-transferrin (fe-tf). addition of manganese (1.5 µg/ml) to the reaction mixture containing iron and apo-tf, reduced fe binding to apo-tf by 20 percent, in comparison to the control sample. the binding of both metals to apo-tf appears to be time and ph dependent processes.using the equilibrium dialysis technique, the binding constant of manganese to apo-tf was also determined. the binding constatnt of mn to apo-tf was calculated, using the scatchard plot analysis. the calculated ka was 3.1×109 m-1.the binding of manganese and iron to human apo-tf has been discussed and compared in this work, using different biochemical techniques.