May be involved sperm-egg plasma membrane adhesion and fusion during fertilization (PubMed:28182716). Exhibits bacteriolytic activity in vitro against Micrococcus luteus and Staphylococcus aureus (PubMed:28182716, PubMed:24013621). Shows weak bacteriolytic activity against Gram-positive bacteria at physiological pH (PubMed:28182716). Bacteriolytic activity is pH-dependent, with a maximum at around pH 5.6 (PubMed:28182716). 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. Detected on the postacrosomal membrane of mature spermatozoa (PubMed:28182716). Expressed in testis, epididymis and spermatozoa (at protein level) (PubMed:16014814, PubMed:28182716). Expressed in late-stage spermatocytes and round spermatids (PubMed:28182716). Belongs to the glycosyl hydrolase 22 family.