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Features of structure, localization, and function of teichoic (TA) and lipoteichoic acids (LPA) of gram-positive bacteria are shortly characterized. Structures of polymers obtained from Streptococcus pyogenes, S. pneumoniae, S. agalactiae are described. The role of TA and LPA of pathogenic streptococci in different phases of infectious process and requirements for biological activity of these molecules are discussed.

The method for the visualization of streptococcal cells, based on the phenomenon of binding between fluorescein isothiocyanate-labeled dextran and the surface structures of streptococci, is proposed. S.cricetus, S.sobrinus and S.faecalis strains were studied. The data obtained in this study were compared with the results of flow cytofluorimetry of these microbial cells. The stability of binding dextrans by microbes and the influence of ionic force on this process were determined at room temperature, +4 degrees C and -20 degrees C.

The authors have developed a method permitting the microscopic study of the morphology of bacteria and their relative position in microcolonies. Thus, the use of this method has made it possible to distinguish Streptococcus pneumoniae from other bacteria by the morphology of their microcolonies. In the study of 75 streptococcal strains, all strains yielding positive results in two or three tests, similarly to all strains pathogenic for mice, formed microcolonies with granular (pneumococcal) morphology, while all strains yielding negative results have been found to form microcolonies with catenulate ("nonpneumococcal") morphology. The authors suggest that the morphology of microcolonies is a more reliable criterion for the identification of S. pneumoniae than other tests used separately.

Cultures of blood from patients with rheumatism during the active and inactive phases of the disease, treated and untreated with antibiotics were studied. The following results were obtained in blood cultures (on Klodnisky's medium with a 0.01% cystine) of 105 patients with rheumatism: L-forms of streptococcus were isolated in the 88 cases, irrespective of the severity of the disease or the treatment, streptococcus--in 8, and the result proved to be negative in 9 cases. Hemoculture on broth with a 1% glucose solution proved to be positive (streptococcus) in one patient only. The constancy with which the L-forms of streptococcus were isolated in hemocultures from the patients with rheumatism and also the peculiarity of their pathogenic properties modelling the rheumatism under experimental conditions pointed to their role in the pathogenesis of rheumatism. A method of isolation of hemocultures on Klodnitsky's medium with a 0.01% cystine can be recommended for the diagnosis of a septic condition caused by the L-forms of streptococcus in patients suffering from rheumatism.