Role of tyrosine and tryptophan residues in loading of iron into ferritin

The protein responsible for iron storage in almost all species is ferritin. Even though ferritin has been an object of research for a long time, there are still a lot of unknowns, like the role of amino acid residues in H-chain ferritin during iron loading into ferritin via its own ferroxidase activity.; In this study I have demonstrated that the loading of iron into ferritin via its own ferroxidase activity results in protein oxidation and as a consequence, its aggregation. I have provided data suggesting that tyrosine residues may be involved in the aggregation and the stability of the ferritin. Also, tryptophan and tyrosine residues play important roles in loading of iron into ferritin by providing ligands to transport iron from the di-iron ferroxidase center to the ferritin core. I also provide evidence that HEPES can protect ferritin against the oxidation resulting from loading of iron into ferritin by its own ferroxidase activity, presumably by trapping the hydroxyl radicals.