Incompatibility and molecular relationships between small bacteriocinogenic plasmids of Staphylococcus aureus.

The sequence relations between small bacteriocinogenic plasmids (pRJ6, pRJ9, pRJ10 and pRJ11) of Staphylococcus aureus were investigated by comparing restriction maps and by hybridization. Plasmids pRJ10 and pRJ11 showed identical restriction maps, similar to that of pRJ9. The restriction map of pRJ6 differed from those of pRJ9 and pRJ10/pRJ11. Both groups of plasmids were shown to share a region of homology of at least 2.6 kb. The incompatibility relationships between them were also investigated by using plasmid derivatives tagged with transposon Tn551. Plasmids pRJ6 and pRJ9 proved to belong to different incompatibility groups.