Induction of proteins during phage reactivation induced by UV irradiation, oxygen and peroxide inBacteroides fragilis

Abstract

Phage reactivation systems in Bacteroides fragilis were induced by far-UV irradiation, O2 and H2O2. These three treatments also induced the synthesis of 3, 6, and 4 protein bands, respectively, which were easily detectable by sodium dodecyl sulfate polyacrylamide gel electrophoresis (SDS-PAGE). Two proteins with apparent Mrs of approx. 90 000 and 70 000 were induced by all three treatments. Caffeine completely inhibited UV- and O2-induced phage reactivation and prevented the synthesis of the Mr 90 000 and Mr 70 000 proteins. The results suggest that these two proteins may be involved in phage reactivation processes induced by UV, O2 and H2O2 in B. fragilis.