In enzymology, a phosphoglucosamine mutase is an enzyme that catalyzes the chemical reaction Hence, this enzyme has one substrate, alpha-D-glucosamine 1-phosphate, and one product, D-glucosamine 6-phosphate. This enzyme belongs to the family of isomerases, specifically the phosphotransferases (α-D-phosphohexomutases), which transfer phosphate groups within a molecule. The systematic name of this enzyme class is alpha-D-glucosamine 1,6-phosphomutase. This enzyme participates in aminosugars metabolism. Crystal structures of two bacterial phosphoglucosamine mutases are known (PDB entries 3I3W and 3PDK), from Francisella tularensis and Bacillus anthracis. Both share a similar dimeric quaternary structure, as well as conserved features of the active site, as found their enzyme superfamily, the α-D-phosphohexomutases.