FIG 5.
Expanded host range susceptibility. The susceptibility levels of various streptococcal strains to bacteriolytic activity of ClyJ or ClyJ-3 were tested in a turbidity assay. Each strain was treated with 25 μg/ml of ClyJ or ClyJ-3 for 20 min, and the decrease in the OD600 was recorded by a microplate reader. The activity of each lysin is expressed as the difference in the decrease in the OD600 between lysin-treated wells and PBS-treated wells [−OD600 = (initial OD600 (lysin-treated well) – final OD600 (lysin-treated well)) − (initial OD600 (PBS-treated well) – final OD600 (PBS-treated well))]. The lytic activity of ClyJ-3 was compared to that of ClyJ by a two-tailed Student's t test. Data are shown as means ± standard deviations. *, P < 0.05.