DRUG RESISTANCE OF STAPHYLOCOCCI. I. TRANSDUCTION OF TETRACYCLINE RESISTANCE WITH PHAGE LYSATES OBTAINED FROM MULTIPLY RESISTANT STAPHYLOCOCCI.

Mitsuhashi, Susumu (Gunma University, Maebashi, Japan), Hiroshi Oshima, Umeko Kawaharada, and Hajime Hashimoto. Drug resistance of staphylococci. I. Transduction of tetracycline resistance with phage lysates obtained from multiply resistant staphylococci. J. Bacteriol. 89:967-976. 1965.-Tetracycline resistance was found to be transduced with phage lysates obtained from multiply resistant strains of Staphylococcus aureus of human origin. With various combinations of multiply resistant donors and tetracycline (TC)-sensitive recipients, almost all of the strains were found to be competent donors. A greater percentage of group 1 staphylococci were competent recipients. Most of the TC(+) transductants were not lysogenic for the transducing phage and were unable to transduce TC resistance with their own phage lysates obtained by ultraviolet irradiation. However, the TC(+) transductants, lysogenized with transducing phage, were capable of transducing TC resistance, and some of the lysogenizations were accompanied by changes in phage type. These results suggest that the emergence of the multiply resistant staphylococci (consistently resistant to TC) can be accounted for by transduction among various strains accompanied sometimes by changes in phage typing pattern after lysogenization, and by selection through extensive use of antibiotics and chemotherapeutic agents.