The inducible Weigle-Reactivation (WR) of UV-irradiated bacteriophage VP5 has been examined in Streptomyces coelicolor A3(2) with and without the mutagenesis-enhancing SCP1 plasmid. A higher inducible reactivation was observed in SCP1+ strains ("free" plasmid) than in SCP1- strains and in NF strains (SCP1 integrated). The efficiency of the plasmid-mediated and cellular repair processes have been examined.