In enzymology, a N-acylglucosamine-6-phosphate 2-epimerase (EC 5.1.3.9) is an enzyme that catalyzes the chemical reaction

N-acyl-D-glucosamine 6-phosphate ${\displaystyle \rightleftharpoons }$ N-acyl-D-mannosamine 6-phosphate

Hence, this enzyme has one substrate, N-acyl-D-glucosamine 6-phosphate, and one product, N-acyl-D-mannosamine 6-phosphate.

This enzyme belongs to the family of isomerases, specifically those racemases and epimerases acting on carbohydrates and derivatives. The systematic name of this enzyme class is N-acyl-D-glucosamine-6-phosphate 2-epimerase. Other names in common use include acylglucosamine-6-phosphate 2-epimerase, and acylglucosamine phosphate 2-epimerase. This enzyme participates in aminosugars metabolism.

As of late 2007, two structures have been solved for this class of enzymes, with PDB accession codes 1Y0E and 1YXY.

• Ghosh S, Roseman S (April 1965). "The Sialic Acids. Iv. N-Acyl--D-Glucosamine 6-Phosphate 2-Epimerase". The Journal of Biological Chemistry. 240: 1525–30. doi:10.1016/S0021-9258(18)97467-3. PMID 14285487.