PURIFICATION, STAPHYLOLYTIC ACTIVITY, AND CLEAVAGE SITES OF ALPHA-LYTIC PROTEASE FROM ACHROMOBACTER-LYTICUS

alpha-lytic protease (alp) was purified from a bacteriolytic agent, Ac hromopeptidase from Achromobacter lyticus M497-1, and has been shown t o possess staphylolytic activity, Cleavage sites of this enzyme on the peptidoglycan of Staphylococcus aureus were determined by N-terminal amino acid sequence and amino acid composition analyses, Alp cleaved t he N-acetylmuramoyl-L-alanine amide bond, the junction between the pol ysaccharide and peptide moieties, in addition to the D-Ala-Gly and Gly -Gly peptide bonds, implying that this enzyme recognizes the amino aci d of D-configuration at the P1 site and possesses N-acetylmuramoyl-L-a lanine amidase activity. However, alp could not cleave the D-Ala-Gly p eptide bond in a synthetic peptide, suggesting that this hydrolytic ac tivity of alp is peptidoglycan-specific. The results obtained from dif ferent consecutive actions of alp and glycosidase on S. aureus peptido glycan indicate that the presence of polysaccharide in the peptidoglyc an is necessary for the bacteriolytic activity of alp.