Lysozymes have primarily a bacteriolytic function; those in tissues and body fluids are associated with the monocyte-macrophage system and enhance the activity of immunoagents. Has antibacterial activity against the Gram positive bacterium P.citreus. Has no antibacterial activity against the Gram negative bacteria E.coli and Y.ruckeri. Does not have hemolytic activity against trout erythrocytes. Hydrolysis of (1->4)-beta-linkages between N-acetylmuramic acid and N-acetyl-D-glucosamine residues in a peptidoglycan and between N-acetyl-D-glucosamine residues in chitodextrins. Optimum pH is 4.5-5.5. No activity above pH 8.8. Optimum temperature is 33-49 degrees Celsius. Retains 25% of its maximal activity after heating 10 minutes at 80 degrees Celsius. Belongs to the glycosyl hydrolase 22 family.