Observations on cysteic acid decarboxylase

Abstract

Extracts from liver of aneurin deficient rats had a lower 1-cysteic acid decarboxylase activity. No increase was obtained after adding aneurin or cocarboxylase in vitro. Feeding expts. indicated that the reduced enzymic activity was due to restricted food intake. No 1-cysteic acid decarboxylase activity was found in extracts of rat kidneys. dl-Homocysteic acid was not decar-boxylated by enzymes prepared from dog or rat livers, but it reduced the rate of decarboxylation of 1-cysteic acid. Active acetone-dried enzyme prepns. were obtained. Removal of the precipitate formed at pH 4.5 from dog liver enzyme prepns. did not impair activity.