An antibiotic enzyme found in egg white. By hydrolyzing certain sugar linkages in glycoproteins, it can dissolve the mucopolysaccharides found in the walls of certain bacteria and hence acts as a mild antiseptic. Its three-dimensional structure has been determined by x-ray crystallography. It is a molecule containing approximately 2200 atoms comprising 129 amino acid units strung together and intricately folded (mw 14,500).