Reaction of peroxyacetyl nitrate with glutathione.

Peroxyacetyl nitrate reacts with the sulfhydryl groups of reduced glutathione. Thioester formation accounts for as much as 50% of the reacted sulfhydryl groups. As much as 60% of the reacted sulfhydryl groups can be accounted for as oxidized glutathione. The stoichiometry of the reaction is approximately 3 moles of sulfhydryl reacting per mole of peroxyacetyl nitrate, and this stoichiometry is the same over the pH range from 4.0 to 8.6 in acetate, phosphate, and tris(hydroxymethyl)aminomethane buffers. Amino acid analyses of reduced and oxidized glutathione after treatment with peroxyacetyl nitrate show that cysteic acid is produced, but not in sufficient quantity to account for the decrease in cysine.