Fig. 4.

Induction of prophages λ (left-side diagrams) and ϕ24_B (right-side diagrams) in MG1655 hosts bearing the pJW0tet vector (closed squares) or either pGAW3775tet (left-side diagrams) or pSBe.x.r.ϕ24_B (right-side diagrams) (open squares), treated with 0.2 μg/ml mitomycin C (a), 50 J/m² UV irradiation (b), or 1 mM H₂O₂ (c) at time 0. Results are shown as PFU (plaque forming units) per cell. The presented results are mean values from three experiments. SD was below 20 % for each point, and is not shown for clarity of presentation