Lysozyme hydrolyzes β(1→4) linkages between N-acetylmuramic acid and N-acetyl-D-glucosamine residues in peptidoglycan and between N-acetyl-D-glucosamine residues in chitodextrin. Gram-positive cells are quite susceptible to this hydrolysis as their cell walls have a high proportion of peptidoglycan. Gram-negative bacteria are less susceptible due to the presence of an outer membrane and a lower proportion of peptidoglycan. However, these cells may be hydrolyzed in the presence of EDTA that chelates metal ions in the outer bacterial membrane.The enzyme is active over a broad pH range (6,0 to 9,0). At pH 6,2, maximal activity is observed over a wider range of ionic strengths (0,02 to 0,100 M) than at pH 9,2 (0,01 to 0,06 M).

Enzyme breaks down the cell walls of bacteria; used to prepare spheroplasts.