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 contai...

5'V NMR is a highly sensitive tool to probe the nature of the metal binding sites of human transferrin (Tf). At a field strength of 11.7 T, the two vanadium(V) binding sites in V,-Tf are characterized by 51V chemical shifts at -529.5 and -53 1.5 ppm versus VOCl,. These shifts are assigned to the Cand N-terminal sites, respectively, based on the 51V NMR spectra of vanadate addition to FeN-Tf and...

Objective(s) Nonenzymatic glycosylation (glycation) occurs in many macromolecules in aging and diabetes due to exposure of biomolecules to high level of glucose. Glycation can changes function, activities and structure of many biomolecules. Considering this important role of transferrin (Trf) in iron transport and antioxidant activity in plasma this study was carried out to investigate the eff...

spectroscopy and by measurements of proton magnetic relaxation rates under conditions in which carbon dioxide (and therefore bicarbonate) is excluded. Even in the absence of bicarbonate, specific binding of Fe3+ to transferrin may occur. Nitrilotriacetate, ethylenediaminetetraacetate, and oxalate were found capable of replacing bicarbonate to form colored complexes with iron and transferrin. Si...

When human erythroleukemic (K562) cells were incubated with 25 microM trifluoperazine (TFP), a drug that inhibits both calmodulin-dependent and calcium-activated phospholipid-dependent kinases, the number of transferrin receptors detected on the cell surface was reduced to approximately half with no change in the affinity of the remaining surface receptors. Removal of the TFP from the incubatio...