Studies on amino-acid dehydrogenase

Abstract

A purified enzyme prepared from pig kidney for the oxidation of dl-proline was studied to determine its relation, if any, to co-enzyme-flavin-enzyme catalysis. The facts that the dehydrogenase was not catalysed by flavin-enzyme and that anaerobic reduction of dyes was slower than the oxidation by molecular oxygen seemed to indicate that flavin-enzyme is not a necessary component of the system. The original enzyme solution heated at 80-90[degree] for 5 min. at pH 8 activated both aerobic and anaerobic oxidation of proline by the dehydrogenase. This activator was dialysable and was destroyed by heating at pH 3 and pH 12 for 5 min. at 90[degree]. It was also inactivated by ultra-violet. Co-zymase. Warburg co-ferment, gluta- thione, adenylpyrophosphate and ascorbic acid did not activate the dehydrogenase.