Transconjugant analysis: limitations on the use of sequence-specific endonucleases for plasmid identification

We used the sequence-specific endonucleases EcoRI, SmaI, BamHI, HsuI, and HaeIII as identification tools in following the conjugal transfer of the well-studied R plasmids Sa, R388, RP4, and R6K. Transfers were both intergeneric and intrageneric. Plasmid fingerprints were generated from both single- and combination-enzyme digests. The Sa transconjugants yielded plasmids showing consistent fingerprints for each of the respective endonucleases used, whereas the three other R-plasmid transconjugants showed fingerprint changes.