Amino acid compositions in peptidoglycans and lysozyme MICs of J1 phage-resistant mutants.

a Amino acid compositions in peptidoglycans were analyzed by high-performance liquid chromatography after samples had been hydrolyzed for 16 h with 6 M HCl at 100°C. Assays were performed in two independent experiments, and the differences of each molar ratio between experiments were less than 10%.
b The cells of L. casei ATCC 27139 and isogenic Tn5 insertion mutants (1.0×107 CFU/ml) were inoculated into fresh ILS broth containing several concentrations of lysozyme. After incubation at 37°C for 48 h, the minimal inhibitory concentration of lysozyme at which L. casei strains failed to grow was regarded as its MIC.