The Raman spectra of selenomethionine and selenocystine

The trace element selenium is known to be a part of the enzyme glutathione peroxidase (glutathione-hydrogen peroxide oxidoreductase, E.C. 1.11.1.9). Studies have shown that selenium in the enzyme exists in at least two forms or oxidation states. It is probable that selenium has been incorporated into the enzyme as the selenocysteine amino acid. In the present study, the Raman spectra of selenocystine and selenomethionine have been obtained, structural assignments have been verified, and the behavior of the two selenoamino acids have been monitored under varying conditions of oxidative stress. The assignments will assist in the interpretation of thespectrum of the actual enzyme.