Open AccessOxygen‐17 Hyperfine Splitting in the Electron Paramagnetic Resonance Spectrum of Enzymically Generated Superoxide
Author(s) -
Bray Robert C.,
Pick Frances M.,
Samuel David
Publication year - 1970
Publication title -
european journal of biochemistry
Language(s) - English
Resource type - Journals
eISSN - 1432-1033
pISSN - 0014-2956
DOI - 10.1111/j.1432-1033.1970.tb01014.x
Subject(s) - electron paramagnetic resonance , xanthine oxidase , chemistry , dithionite , oxygen , hyperfine structure , xanthine , superoxide , paramagnetism , photochemistry , nuclear magnetic resonance , inorganic chemistry , analytical chemistry (journal) , atomic physics , physics , biochemistry , organic chemistry , quantum mechanics , enzyme
The electron paramagnetic resonance spectrum of 17 O in O 2 − generated by reduction of O 2 by two related systems has been observed using the rapid freezing method. The systems were: (a) during re‐oxidation of xanthine oxidase following reduction with dithionite and (b) during steady‐state oxidation of xanthine catalysed by xanthine oxidase. The spectrum was similar to that reported for O 2 − adsorbed on MgO. Both the 11‐line spectrum from 17 O 17 O− and the six‐line spectrum from 17 O 16 O− were detected. The results provide final confirmation that one‐electron reduction of oxygen can occur in biological systems.