The specificity requirements of bacteriophage T4 lysozyme. Involvement of N-acetamido groups.

Bacillus cereus peptidoglycan with N-unsubstituted glucosamine residues was insensitive to treatment with bacteriophage T4 lysozyme. After N-acetylation with acetic anhydride, T4 lysozyme cleared solutions of the peptidoglycan and reducing sugars were liberated. The digestion products were mainly of high molecular weight, since the peptidoglycan is peptide cross-linked to a great extent. N-Propylation did not convert the partially N-unsubstituted peptidoglycan to a sensitive form. It is concluded that the acetamido groups are required for binding and/or catalysis by T4 lysozyme.