Iron and copper are essential trace elements, which in certain conditions, namely in the ionised form or in
low-molecular complexes, can participate in single electron reactions and catalyse formation of free radicals,
including the dangerous hydroxyl radical. Similar behavior have also some other transitive metals. Our overview is
aimed on the role of transitive elements in the formation of free radicals and on the mechanisms that organisms have
to prevent it. The highest attendance is given to the metabolism of iron and cooper. Consistent protection against
free transitive metals (by binding with proteins, by oxidation or sequestration in a special compartment) enables
organism to use their beneficial and required features without impairment of cell. Knowledge of these mechanisms
provides the means to predict and effectively prevent the brake down of such defend systems in situations of the
intravascular hemolysis, hemodialysis, administration of iron, impairments of the iron and copper metabolism,
intoxication by oxidising substances etc.
transitive metals, copper, iron, free radicals, Fenton’s reaction.