title: ESR studies on oxidation state changes of copper in superoxide dismutase during reactions with water radiolysis products at cryogenic temperatures.
abstract: Irradiating the aqueous solutions of native and reduced superoxide dismutase with 60Co gamma-rays at 77 K and recording the ESR spectra during thermal annealing the formation and decay of the complexes E-Cu2+...HO2 and E-Cu+...HO2 have been observed. Decay of ESR signals corresponding to HO2 in these complexes is not accompanied by immediate changes of the oxidation state of copper. The delayed changes of copper oxidation state are probably due to the reactions of dismutation products with superoxide dismutase.
mesh_terms: D000818:Animals; D002417:Cattle; D003037:Cobalt Radioisotopes; D003080:Cold Temperature; D003300:Copper; D004578:Electron Spin Resonance Spectroscopy; D004912:Erythrocytes / Q000201:enzymology; D010084:Oxidation-Reduction; D013482:Superoxide Dismutase / Q000097:blood / Q000528:radiation effects*; D014867:Water / Q000528:radiation effects*
chemical_list: D003037:Cobalt Radioisotopes; D014867:Water; D003300:Copper; D013482:Superoxide Dismutase