Superoxide Dismutases from Escherichia coli

Three superoxide dismutases have so far been isolated in crystalline form from Escherichia coli. Their active sites contain either manganese, iron or copper and zinc ions. The monomeric manganese and iron compounds are coordinatively similar, but the Cu/Zn enzyme is a dimer with a bridging histidine residue.

Manganese superoxide dismutase

Iron superoxide dismutase

Copper/zinc superoxide dismutase