Ferritin, the path of iron into the core, as seen by Mössbauer spectroscopy

Ferritin, the ubiquitous iron storage protein, has been widely studied by a variety of techniques. The paper reviews Mössbauer studies on horse spleen and human recombinant ferritins, which helped to reveal the pathway iron follows from its uptake by the protein from a solution of Fe₂SO₄ to the building of the iron core of ferritin. Five different Fe(III) species and two Fe(II) species were observed, among them a peroxo-bridged and an oxo-bridged dimer, a monomer, small iron clusters and large iron aggregates. Transfer of iron between ferritin molecules was established.