OXIDATION OF THE S-METHYL GROUP BY TISSUE PREPARATIONS.
Final rept. 1 Jun 61-15 Oct 65,
STATE UNIV OF NEW YORK ALBANY RESEARCH FOUNDATION
Pagination or Media Count:
An enzymic activity was detected in tissue homogenates capable of oxidizing the methyl group of methionine and other S-methyl compounds, completely to carbon dioxide. The activity is present in the highest concentrations in liver and kidney smaller concentrations are found in brain, heart, skeletal muscle, and erythrocytes. Stable semi-purified preparations were prepared from rat liver. Experiments with crystalline beef liver catalase and the rat liver enzyme preparations clearly demonstrated the involvement of catalase in the S-methyl group oxidation process. Various hydrogen peroxide generating systems, both enzymic and chemical, can propagate the peroxidation of the s-methyl groups by catalase. Highly purified rat liver catalase was isolated and was shown to possess similarperoxidation properties as does beef liver catalase. Addition of soluble fractions from rat liver markedly stimulates the peroxidation of S-methyl groups by the rat liver catalase. The involvement of catalase in the oxidation of S-methyl groups to carbon dioxide in vivo was demonstrated by experiments with 3-amino-1,2,4-triazole. This compound inhibits both the catalatic and methyl oxidizing activities of rat liver in a generally proportional manner. Author