Enzymes acting on glucosamine phosphates

The chemical synthesis of α-acetylglucosamine-i-phosphate and some of its properties are described. From kidney or liver, enzymes have been obtained which catalyse the following reactions: α-acetylglucosaminei-phosphate ⥮ acetylglucosamine-6-phosphate (1) N- acetylglucosamine-6-phosphate⥮fructose-6-phosphate + NH3 + acetate (2) glucosamine-6-phosphate⥮fructose-6-phosphate + NH3 (3) Reaction (1) was found to be activated by magnesium ions. The enzyme(s) responsible for reactions (2) and (3) were purified and it was observed that (3) requires catalytic amounts of N-acetylglucosamine-6-phosphate (or of the N-propionyl derivative) and that it is reversible. The possible mechanism of the reactions is discussed.