DNA replication in bacteriophage-infected Staphylococcus aureus.

The synthesis of viral and host DNA in phage-infected Staphylococcus aureus was examined. Three intracellular forms of phage 52HJD DNA were demonstrated: covalently closed circular, open circular, and linear DNA species. It was noted that infection of S. aureus-propagating strains 81 and 52 with phage 52HJD inhibited the replication of the bacterial chromosome and a stringently controlled penicillinase plasmid. A small tetracycline plasmid, normally under relaxed replication control, continued to replicate in the postinfection period. No breakdown of the host chromosome into small-molecular-weight fragments or utilization of bacterial DNA material for the synthesis of viral DNA was observed.