In:
European Journal of Biochemistry, Wiley, Vol. 137, No. 1-2 ( 1983-12), p. 29-36
Abstract:
The reaction of superoxide with reduced glutathione (GSH) was studied with two O 7 2 ‐producing systems: xanthine oxidase using xanthine or acetaldehyde as substrates and, secondly, quinol autoxidation. The capability of GSH to quench superoxide radicals was detected by lowered O 7 2 ‐mediated cytochrome c 3+ reduction. The formation of the oxidation products, glutathione disulfide (GSSG) and glutathione sulfonate (the latter at levels of about 6–15% compared to GSSG), was dependent on the O 7 2 ‐production and was inhibited by superoxide dismutase. The presence of GSH together with an O 7 2 ‐producing system led to an extra uptake of oxygen, which was also depressed by superoxide dismutase. The observed O 2 uptake was accounted for by the formation of GSSG and GSO − 3 from GSH; the data are in accordance with a mechanism involving thiyl radicals. Low‐level chemiluminescence measurement indicated the formation of excited oxygen species. The intensity of photoemission was dependent on the GSH concentration and on the O −· 2 production rate. Chemiluminescence was inhibited by superoxide dismutase and also by glutathione peroxidase, but not by catalase or OH · quenchers. Spectral analysis and the effects of 1,4‐diazabicyclo[2.2.2]octane and sodium azide indicated the contribution of singlet molecular oxygen to the light emission. It is suggested that singlet oxygen results from an intermediate oxygen addition product such as a glutathione peroxysulphenyl radical.
Type of Medium:
Online Resource
ISSN:
0014-2956
,
1432-1033
DOI:
10.1111/ejb.1983.137.issue-1-2
DOI:
10.1111/j.1432-1033.1983.tb07791.x
Language:
English
Publisher:
Wiley
Publication Date:
1983
detail.hit.zdb_id:
1398347-7
detail.hit.zdb_id:
2172518-4
SSG:
12
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