[Kasugamycin methylase modified by ribosomal RNA from group A streptococci].

Kasugamycin sensitivity in Escherichia coli depends on the specific enzyme methylating rRNA. Native group A streptococci (GAS) were found to be sensitive to kasugamycin. After introduction of the erythromycin gene located on the transposon Tn916E into GAS some of the strains obtained kasugamycin resistance together with erythromycin resistance (erm).

[Conjugation in streptococci].

The problem of conjugation in Streptococci is reviewed as a form of genetical information exchange in bacteria. The theoretical and experimental data of the recent years on the nature, mechanisms and role of conjugation in the spreading of drug resistance in the populations of pathogenic microorganisms are presented.

[Comparative aspects of adhesion of group A and B streptococci to human epithelium].

The international and original research data on the adhesion of group A and B streptococci are over-viewed. Based on the conducted studies, a conclusion has been drawn on the polyfactor pattern of pathogenic streptococci adhesions. The polyfactor pattern of adhesion is manifested in (a) different ranges of tissue sensitivity to streptococci adhesion, (b) a correlation between the adhesiveness and particular phenotypes (M(+)-M-; OF(+)-OF- in group A streptococci, TSA(+)-TSA- in group B streptococci), (c) different sensitivity of adhesives to proteolytic enzymes, and (d) interaction with fibronectin.

[Conjugation in group A streptococci].

The paper presents data on the nature of the conjugation-like process (CLP) of genetic marker transfer on the membrane filters in group A streptococci. Studied are the CLP development depending on the duration of the donor-recipient contact and the influences of various physiological conditions on the degree of CLP manifestation and frequency. The effect of sub-inhibiting erythromycin concentrations on the frequency of the erythromycin marker transfer is first found.