Physical characterization of the Clostridium perfringens tetracycline-chloramphenicol resistance plasmid pIP401.

Four restriction endonucleases were used to construct a physical map of the tetracycline-chloramphenicol resistance plasmid pIP401, which had been isolated from Clostridium perfringens. Twenty-seven restriction sites were placed within the 52-kb map, including 1 site for AvaI, 2 sites for KpnI, 10 sites for EcoRI and 14 sites for PstI. The loss of chloramphenicol resistance in the derived pIP406 plasmid was associated with a deletion of a 6.2-kb DNA segment located in a 10.55 EcoRI-PstI fragment. Two 1.4-kb inverted repeats were also characterized in both pIP401 and pIP406.