N-Acetylmuramic acid


N-Acetylmuramic acid, or MurNAc, is the ether of lactic acid and N-acetylglucosamine with the chemical formula. It is part of a biopolymer in the bacterial cell wall, which is built from alternating units of N-acetylglucosamine and N-acetylmuramic acid, cross-linked with oligopeptides at the lactic acid residue of MurNAc. This layered structure is called peptidoglycan.
MurNAc is a monosaccharide derivative of N-acetylglucosamine.

Clinical significance

N-Acetylmuramic acid is part of the peptidoglycan polymer of bacterial cell walls. MurNAc is covalently linked to N-acetylglucosamine and may also be linked through the hydroxyl on carbon number 4 to the carbon of L-alanine. A pentapeptide composed of L-alanyl-D-isoglutaminyl-L-lysyl-D-alanyl-D-alanine is added to the MurNAc in the process of making the peptidoglycan strands of the cell wall.
Synthesis is inhibited by fosfomycin.