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Intramolecular hydrogen transfer reactions of thiyl radicals from glutathione: formation of carbon-centered radical at Glu, Cys, and Gly.

ABSTRACT: Glutathione thiyl radicals (GS(•)) were generated in H(2)O and D(2)O by either exposure of GSH to AAPH, photoirradiation of GSH in the presence of acetone, or photoirradiation of GSSG. Detailed interpretation of the fragmentation pathways of deuterated GSH and GSH derivatives during mass spectrometry analysis allowed us to demonstrate that reversible intramolecular H-atom transfer reactions between GS(•) and C-H bonds at Cys[(?)C], Cys[(?)C], and Gly[(?)C] are possible.

SUBMITTER: Mozziconacci O

PROVIDER: S-EPMC3736831 | biostudies-literature | 2012 Sep

REPOSITORIES: biostudies-literature

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Intramolecular hydrogen transfer reactions of thiyl radicals from glutathione: formation of carbon-centered radical at Glu, Cys, and Gly.

Mozziconacci Olivier O Williams Todd D TD Schöneich Christian C

Chemical research in toxicology 20120703 9

Glutathione thiyl radicals (GS(•)) were generated in H(2)O and D(2)O by either exposure of GSH to AAPH, photoirradiation of GSH in the presence of acetone, or photoirradiation of GSSG. Detailed interpretation of the fragmentation pathways of deuterated GSH and GSH derivatives during mass spectrometry analysis allowed us to demonstrate that reversible intramolecular H-atom transfer reactions between GS(•) and C-H bonds at Cys[(α)C], Cys[(β)C], and Gly[(α)C] are possible. ...[more]

PMID: 22712461

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