Fig 2.

PlyB-mediated killing of B. cereus. (A) Overnight cultures of B. cereus were washed and incubated with PlyB at 125 µg/mL in PBS, pH 7.4 for 2.5, 5, 10, 30, and 60 minutes at 37°C. Viable bacteria were quantified by serial dilution and plating. PlyB reduced the B. cereus count by 2 log₁₀ within 2.5 minutes and greater than 5 log₁₀ by 5 minutes. (B) B. cereus in stationary phase, logarithmic phase, and spores were washed and incubated with PlyB at 125 µg/mL in PBS, pH 7.4 for 60 minutes at 37°C, and viable bacteria were quantified as noted above. PlyB killed stationary and logarithmic phase B. cereus but not Bacillus spores. Values represent means ± SEM of n ≥5 with at least two independent experiments. *P ≤ 0.05.