Figure 3.

Effect of DNA damage on BsSSB phosphorylation. (A) Control kinase reaction is shown in lane 1. The same reaction was performed in presence of increasing amounts of ssDNA (lanes 2–5) and dsDNA (lanes 6–9). (B) BsSSB phosphorylation followed by anti-PY western blotting in B.subtilis strain SPSSBHT, with and without 60 ng/ml mitomycin C (added at 1.5 h). Samples from both cultures were taken at regular time intervals and anti-PY western blotting was performed with equal quantities (about 50 ng) of purified BsSSB. Growth of B.subtilis SPSSBHT-ΔywqD and B.subtilis SPSSBHT strains was compared in DNA damaging conditions. Mitomycin treatment was the same as above, the OD₆₀₀ (C) and the colony forming ability (D) of the growing cultures were monitored. One representative of four independent experiments is shown.