Loss of the penicillinase plasmid after treatment of Staphylococcus aureus with sodium dodecyl sulfate.

Two strains of Staphylococcus aureus (PC1 and 196E), when grown in medium containing 0.002% sodium dodecyl sulfate (SDS), showed from 96.1 to 100% loss of the ability to produce penicillinase. Resistance to cadmium and zinc was lost concomitantly with the ability to produce penicillinase. A comparison of the rate of curing by SDS with the curing effects exerted by elevated temperature and ethidium bromide suggested that SDS is a more effective plasmid curing agent for susceptible strains of S. aureus than methods in use at present.