title: Relation between ESR-detectable Cu(II) and superoxide dismutase activity.
abstract: The relation between ESR-detectable Cu(II) and Cu,Zn-superoxide dismutase activity was examined. The Cu(II) spin numbers per one unit of SOD were 6.26 X 10(12) (+/- 0.51 X 10(12] spins in several preparations of recombinant human Cu,Zn-SOD, native placental, and erythrocyte SOD. Measurement could be performed over a wide range of pH (4.0-10.0), preferably at temperatures below -40 degrees C. The data obtained by this method correlated well to the results obtained by the method of Fridovich et al. using the xanthine-xanthine oxidase system (correlation coefficient 0.995). The specific activity of SOD was proportional to the Cu(II) content measured by ESR, but not to the total Cu content measured by atomic absorption. This indicates that it is important to measure the Cu(II) content for determining Cu,Zn-SOD activity.
authors.affiliation: Research Laboratories, Nippon Kayaku Co., Ltd., Tokyo.
authors.forename: J
authors.initials: J
authors.lastname: Kajihara
authors.forename: M
authors.initials: M
authors.lastname: Enomoto
authors.forename: K
authors.initials: K
authors.lastname: Katoh
authors.forename: K
authors.initials: K
authors.lastname: Mitsuta
authors.forename: M
authors.initials: M
authors.lastname: Kohno
mesh_terms: D003300:Copper / Q000032:analysis*; D004578:Electron Spin Resonance Spectroscopy; D004912:Erythrocytes / Q000201:enzymology*; D005260:Female; D006801:Humans; D006863:Hydrogen-Ion Concentration; D010920:Placenta / Q000201:enzymology*; D011247:Pregnancy; D011994:Recombinant Proteins / Q000378:metabolism; D013482:Superoxide Dismutase / Q000097:blood / Q000378:metabolism*; D013696:Temperature
chemical_list: D011994:Recombinant Proteins; D003300:Copper; D013482:Superoxide Dismutase