Distribution, purification and properties of 1-aspartamido-beta-N-acetylglucosamine amidohydrolase.

1. The activity of the enzyme that splits 2-acetamido-1-l-beta-aspartamido-1,2-dideoxy-beta-d- glucose (1-aspartamido-beta-N-acetylglucosamine) was measured in tissues from different mammalian species. 2. The enzyme from an aqueous extract of rat liver was purified 150-fold in 56% yield. 3. Optimum activity for the hydrolysis of 1-aspartamido-beta-N-acetylglucosamine was at pH7, and ammonia and N-acetylglucosamine were liberated in equimolar amounts. At pH8.5, 1-amino-N-acetylglucosamine was the only sugar produced after short periods of incubation. On prolonged incubation there was spontaneous liberation of ammonia from this compound. 4. It is concluded that the enzyme is an amidase.