TRANSDUCTION OF RESISTANCE TO CHLORTETRACYCLINE AND NOVOBIOCIN IN STAPHYLOCOCCUS AUREUS

Abstract

Using phage 80 of the International Typing Series propagated on appropriate strains of Staphylococcus aureus, resistance to chlortetracycline and novobiocin and the capacity to produce penicillinase were transduced to a number of antibiotic-sensitive recipient strains of S. aureus. The frequency of transduction varied from 1 to 10 transductants per 107 phage particles employed. Lysogenization of the transductants by the transducing phage did not occur. Phages 29, 52A, 79, and 53 of the International Typing Series were also capable of transduction, while phages 42B and 81 were unable to participate under the conditions used. The recipient strains were either resistant or susceptible to lysis by the transducing phages, but this did not influence the transduction frequencies. Lysis of transductants susceptible to the transducing phages was inhibited by preparing the selective medium with brain heart infusion agar. Linked transductions were not detected. With few exceptions, all of the recipient strains were susceptible to lysis by phages of group I or phage 81 or both. Strains susceptible to lysis by phages of groups II and III, but resistant to lysis by phages of group I or phage 81, were not transduced.