Amino acid decarboxylases in rat brain and liver

Abstract

1. 1. Liver cysteine sulphinic acid decarboxylase is found in the clear supernatant of a liver suspension after fractional centrifugation, while brain cysteine sulphinic acid decarboxylase is more or less associated with particulate matter. 2. 2. Thiol groups and pyridoxal phosphate are shown to be necessary for the activity of liver and brain decarboxylases. 3. 3. Further evidence is presented to suggest that cysteine sulphinic and cysteic acids are decarboxylated by the same enzyme in the liver. 4. 4. Evidence is also given that glutamic, cysteine sulphinic and cysteic acids are decarboxylated by the same enzyme in the brain.