ABSTRACT
Iron is an abundant transition metal, characterized by its redox reactivity to switch between two basal ferrous Fe(II) and ferric Fe(III) states, and by its capacity to form a variety of co-ordination complexes with organic ligands. Virtually, all living cells and organisms (with a few minor exceptions) exploit these advantageous chemical properties and utilize iron, as component of iron-containing metalloproteins, to accomplish vital structural and metabolic functions. These include oxygen sensing and transport, and a plethora of electron transfer and catalytic reactions (1). Iron co-ordinates to
metalloproteins in a dynamic and flexible mode, either in form of heme or not (2).
