Iron is an essential element for diverse biological functions. In mammals, the majority of iron
is enclosed within a single prosthetic group: heme. In metazoans, heme is synthesized via a
highly conserved and coordinated pathway within the mitochondria. However, iron is
acquired from the environment and subsequently assimilated into various cellular pathways,
including heme synthesis. Both iron and heme are toxic but essential cofactors. How is iron
transported from the extracellular milieu to the mitochondria? How are heme and heme …