FIG. 1.

Genetic organization of the type III R/M system in pND801. The 12-kb plasmid pND801 was cloned into pSA3 to generate pND805, which expressed resistance to φ712. Locations of the Tn5 insertions in pND805 are shown (triangles, Tn5 insertions which inactivated phage resistance; ellipses, Tn5 insertions which did not affect the phage resistance phenotype). The locations of the mod gene and the res gene, the sequences of the putative promoter and the ribosome-binding site (RBS), and the position of the transcriptional terminator (ellipse with vertical line) are shown. The start codon of the res gene overlaps the stop codon of the mod gene.