Manganese ions, oxidation reactions and the superoxide radical.

The variable valency of the transition element manganese allows it to catalyse redox reactions. This can be made use of in mangano -superoxide dismutase enzymes, but manganese-induced oxidation of NADH and dihydroxyflumarates generate damaging oxygen radicals. Manganese-stimulated oxidations of adrenalin and its derivatives to form toxic products may be involved in the etiology of manganese neurotoxicity.