Laboratory observations on the lysogenic properties of hospital staphylococci and their possible epidemiological implications

Lysogeny in staphylococci

Blair, John E. (Hospital for Joint Diseases, New York, N. Y.) and Miriam Carr. Lysogeny in staphylococci. J. Bacteriol. 82:984-993. 1961.-Changes in the phage typing patterns of strains of staphylococci of the 80/81-52/52A/80/81 complex and of phage group III were produced by lysogenization with temperate phages derived from selected strains of Staphylococcus aureus. The phages used were of the serological groups A, B, and F. Certain changes of phage pattern were related to serologically specific prophage immunity; others were nonspecific, or resulted from the conversion of a strain from partial resistance to full sensitivity to certain typing phages. In addition to an alteration of their phage typing pattern, the lysogenization of certain strains by appropriate phages effected a reversal of their susceptibility to penicillin. The capacity to produce toxin was conferred upon certain nontoxigenic strains by lysogenization with a phage derived from a toxigenic strain.

Typing of nontypable staphylococci by lysogeny

Strains of coagulase-positive staphylococci which were nontypable with the routine typing set of phages could be typed by lysogeny with phage-propagating strains as indicators and with ultraviolet induction. About 10% of the strains could be typed without induction. About 36% of them could be typed by this method when ultraviolet irradiation was used as an inducing agent. The phage groups from which the majority of the nontypable staphylococci originated were easily identified by this method of typing.

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.