Plasmid pT181-linked suppressors of the Staphylococcus aureus pcrA3 chromosomal mutation.

Plasmid pT181 replication is affected in hosts carrying the chromosomal pcrA3 mutation, resulting in significantly lower plasmid copy numbers. Mutations suppressing this effect have been isolated and characterized. The suppressor mutations were found to map in the plasmid repC gene and manifested pcrA allele specificity, suggesting the existence of a direct RepC-PcrA interaction.