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 (By similarity). Has bacteriolytic activity against Gram-positive bacterium M.luteus, and Gram-negative shrimp pathogenic bacteria V.alginolyticus, V.parahaemolyticus and V.vulnificus. May play a role in host defense (PubMed:18798009). 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. Monomer. Strongly expressed in gill and gonad, and marginally detectable in hemolymph and lymphoid organ. Not expressed in kidney, hepatopancreas or tail muscle. (Microbial infection) Expression is up-regulated in response to heat-killed V.alginolyticus injection in kidney, hepatopancreas and muscle, with the strongest up-regulation in hemolymph, gill, gonad and lymphoid organ. After M.luteus challenge there is an increase in expression level at 2 (11.3-fold) and 6 hours (18.3-fold) postinjection, with the maximum level at 8 hours (25.4-fold), and then lowering down to the original level at 16 hours postinjection. After V.alginolyticus challenge there is significant increase in expression level at 4, 6 and 8 hours postinjection, with the maximum level at 16 hours (15.7-fold), and then down-regulated at 24 hours postinjection. Lysozyme C is capable of both hydrolysis and transglycosylation; it shows also a slight esterase activity. It acts rapidly on both peptide-substituted and unsubstituted peptidoglycan, and slowly on chitin oligosaccharides. Belongs to the glycosyl hydrolase 22 family.