'Glucosamine-6-phosphate is an important metabolic precursor of all the amino sugars. It is synthesized from glutamine and fructose-6-phosphate in a reaction catalyzed by glutamine:fructose-6-phosphate amidotransferase. Glucosamine-6-phosphate is subsequently converted to UDP-N-acetylglucosamine, as shown in Figure 16.13.

Glucosamine-6-phosphate is an allosteric inhibitor of glutamine synthetase, an enzyme central to nitrogen metabolism in the cell.