Streptococcus group A resistance to tetracycline: its spread and transduction]

The study on antibiotics resistance of group A streptococci isolated in 1977 showed that the number of the antibiotic resistant strains had significantly increased as compared to the data of 1960. High percentage (53%) of the cultures with multiple resistance was noted. It was observed that the number of the streptococcal cultures resistant to erythromycin and chloramphenicol decreased while the number of the strains resistant to tetracyclines increased. The level of resistance to tetracycline increased more than 2 times from 1960 and in some cases reached 125 and 250 gamma/ml. The wide spread of tetracycline resistance was evident of the presence of the mechanism of the marker transduction. Possible transduction of this feature was studied. Microbe-free phagolysates obtained by induction with UV-light from the strains with multiple antibiotic resistance were used as the donor material in the experiment on transduction. Principal possibility of transducing resistance to tetracycline from 2 donors to 4 recipients at a frequency of 10(-6) was shown.