Lysostaphin-induced lysis assay

The overnight cultures of different S. aureus strains were 1:100 diluted into fresh TSB with the supplementation of 75 μM DHBP when indicated. The cells were grown to an OD₆₀₀ of 1.2–1.7 before harvesting (10 min, 5,400g). The harvested cells were resuspended in PBS to make bacterial suspensions with an OD₆₀₀ of∼1, which were further supplemented with 200 ng ml⁻¹ lysostaphin. The suspensions were incubated at 37 °C with aeration and OD₆₀₀ was monitored at different time points. The measured OD₆₀₀ was normalized by dividing the initial OD₆₀₀ for presentation.