title: Electron-electron double resonance measurements on xanthine oxidase.
abstract: Electron-electron double resonance measurements were carried out on milk xanthine oxidase (xanthine:oxygen oxidoreductase EC 1.2.3.2) and the spectra obtained supported a previous model, based on EPR data, proposing a spin-spin interaction between unpaired electrons associated with Fe-S and Mo. The technique demonstrated that the additional apparently isotropic, splitting in the Mo EPR spectra observed at low temperature is produced by a single site giving two spectra interconverting at a rate consistent with the Fe-S spin lattice relaxation time. Other data concerning the model and the relaxation behaviour of the species are discussed.
mesh_terms: D000818:Animals; D002417:Cattle; D003903:Deuterium; D004578:Electron Spin Resonance Spectroscopy; D007501:Iron; D008892:Milk / Q000201:enzymology; D008982:Molybdenum; D013455:Sulfur; D014969:Xanthine Oxidase
chemical_list: D013455:Sulfur; D008982:Molybdenum; D003903:Deuterium; D007501:Iron; D014969:Xanthine Oxidase