[The SOS and catabolytic repression systems can play a key role in the regulation of infection of Escherichia coli cells with F-specific filamentous phages M13, f1 and fd].

Theoretical analysis of DNA sequences revealed recognition sites for two global E. coli cellular regulons in M13, fd and fl phage's genomes. Both Px and Pv promoters have SOS operator sequences and therefore must be repressed by the lexA protein. PIII and PIV contains CRP-cAMP recognition sequences in activating positions and hence will be activated by the cAMP receptor protein. The model is proposed for the phage life cycle's control in the persistent infection of E. coli cells by F-specific filamentous phages.