Molecular and functional aspects of bacteriophage endolysins

Following infection and replication, phages depend on host lysis to release their progeny in the environment. This is accomplished by the regulated expression of lysis proteins at the end of the lytic cycle. One of these proteins is the endolysin, an enzyme that specifically degrades the bacterial peptidoglycan layer, consisting of alternating residues of -(1,4) linked N-acetylglucosamine and N-acetylmuramic acid, linked by a peptide chain of three to five amino acids.