[The M-protein heterogeneity of Streptococcus pyogenes strains isolated from clinically healthy and ill children in an organized collective]. / Geterogennost' po M-belku shtammov Streptococcus pyogenes, vydelennykh ot klinicheski zdorovykh i bol'nykh detei v organizovannom kollektive.

The study of the kinetic curves of the lysis of group A S. pyogenes cell-walls (cells), serovars 29 and 12 M, variants M+ and M-; with endo-N-acetyl-muramidase revealed that the kinetics of the lysis of virulent and avirulent strains was different: variant M- was lyzed faster than M+. This difference in the cell-wall lysis of both variants made it possible to use this method for the identification of M+ and M- states of the strains. 18 group A S. pyogenes cultures were studied. The cultures isolated from healthy and sick children in an organized group belonged to variants both M+ and M-. The pepsin fragments of M-proteins of group A S. pyogenes, type M 1, isolated in dynamics from a carrier and a patient, were studied. Their amino acid compositions were studied, and differences between them were established. The data thus obtained indicate that heterogeneity is characteristic of both the surface structure of streptococci and the individual components of their surface, in particular, M-protein.

[The heterogeneity of Streptococcus pyogenes strains isolated from clinically healthy and sick children in an organized collective]. / Geterogennost' shtammov Streptococcus pyogenes, vydelennykh ot klinicheski zdorovykh i bol'nykh detei v organizovannom kollektive.

Experiments on typed strains used as an example revealed that kinetic curves obtained in the lysis by endo-N-aretylmuramidase of virulent strains greatly differed from those obtained from nonvirulent ones: the lysis rate of M+ variants was less than that of M- variants; M- strains gave rather steep kinetic curves of lysis, while those of M+ strains were more declivous. In this study group A S. pyogenes cultures isolated from healthy and sick children in a summer camp were used. The study revealed that cultures, newly isolated from healthy and sick children, were heterogeneous with respect to the M+ and M- state of group A S. pyogenes strains, the amino acid composition of pepsin fragments of M-proteins in the cultures of streptococcus M 1 under study being also heterogeneous.

[The biochemical and immunological properties of group A type M 29 streptococci cultured in the presence of a bovine blood serum preparation]. / Biokhimicheskie i immunologicheskie svoistva streptokokkov gruppy A tipa M 29, kul'tivirovannykh v prisutstvii preparata iz syvorotki krovi krupnogo rogatogo skota.

The influence of the preparation of cattle blood serum on group A streptococcus, type M 29, has been studied. The study has revealed that the addition of 17% of dialysis water obtained from a fraction of cattle blood serum to the standard culture medium (3% Todd-Hewitt broth) produces changes in the amino acid composition of the cell walls of M+ variant without altering the antiphagocytic resistance of the mutant thus obtained. The dialysate of the pepsin digest of the cell walls of the mutant contains Fc-receptors and receptors to fibrinogen, while the initial strain contains only receptors to fibrinogen which are, in this case, the pepsin fragments of M protein. The study has revealed similarity in the amino acid compositions of these proteins (receptors to fibrinogens) of phenotypes M+ and M2+. Thus, our data confirm that the initial strain and the mutant belong to different phenotypes of group A streptococcus, type M 29.

[The modification of the cell wall proteins in group A streptococci type M 29 under the influence of spermidine contained in the culture medium]. / Modifikatsiia belkov kletochnykh stenok streptokokkov gruppy A tipa M 29 pod deistviem spermidina, soderzhashchegosia v srede kul'tivirovaniia.

The addition of spermidine into growth medium used for the cultivation of group A streptococci, type M 29, leads to changes in the amino acid composition of cell walls and surface proteins isolated by the method of E. H. Beachey et al. The separation of surface proteins into fibrinogen-binding proteins and fibrinogen receptors by affinity chromatography techniques on cellulose with covalently bound fibrinogen indicates that the proportion of these proteins in pepsin extracts obtained from different strains varies. Both spermidine and avirulent strains have similar content of fibrinogen-binding proteins, although these proteins are absent in virulent strains. Different amounts of fibrinogen receptors are extracted from all strains. As shown in the enzyme immunoassay, fibrinogen receptors contain no group-specific polysaccharide A, Fc-receptors and interact with total antiserum to group A streptococci, type M 29 [correction of 28]. Fibrinogen receptors isolated from the strains under study have been found to have similar amino acid composition. On the basis of these results we believe that neither receptor capacity to fibrinogen nor amino acid composition is indicative of the protective properties of protein M.

[A study of the variability of group A type M29 streptococcus on exposure to biologically active substances]. / Izuchenie izmenchivnosti streptokokka gruppy A tip M29 pri vozdeistviina nego biologicheski aktivnykh veshchestv.

Biologically active substances spermidine and the compounds contained in the low-molecular fraction of cattle blood serum change the phenotype of type 29 group A Streptococcus. Amino acid analysis and enzymatic destruction of cell walls have demonstrated changes of the streptococcal biological characteristics and cell wall structural organization. These changes may result from loss of supervariable component of the M-protein when compounds from cattle blood serum low-molecular fraction are added to culture medium and by unbalanced growth of Streptococcus after spermidine addition to growth medium.

[The physicochemical and biochemical characteristics of the cell walls in M+ and M- variants of Streptococcus group A type 29]. / Fiziko-khimicheskaia i biokhimicheskaia kharakteristika kletochnykh stenok M+ i M--variantov streptokokka gruppy A tipa 29.

The amino acid composition of cell walls and surface proteins, isolated from virulent (M+) and avirulent (M-) streptococcal strains (group A, type 29) has been determined by the method of E. H. Beachey et al. The kinetics of the lysis and proteolysis of streptococcal cell walls with muramidase and protease obtained from Actinomyces levoris and streptolysin has been studied. The constants describing the progress rates of these processes has been determined; their values in case of both lysis and proteolysis are higher in virulent strains than in avirulent ones.

[The effect of blood serum components on the growth, biochemical and biological properties of streptococcus]. / Vliianie komponentov syvorotki krovi na rost, biokhimicheskie i biologicheskie svoistva streptokokka.

The components of cattle blood serum, added to the medium for the cultivation of group A streptococci, considerably decrease the period of adaptation and increase the balanced growth rate of streptococci, which is manifested by changes in the surface structures of the cell wall: the absence or modification of protein M. Streptococci grown under these conditions lose their capacity for phagocytosis, and from the cell walls obtained from these streptococci no surface protein M can be isolated by pepsin treatment. Nevertheless, the ratio of the main cell-wall components (proteins, polysaccharide and peptidoglycan), the amino acid composition, as well as the resistance of the cell walls to the action of trypsin and endo-N-acetylmuramidase are the same in M+ and Mx variants, that makes it possible to infer that the modification of protein M or the inhibition of its synthesis occurs during the growth of streptococci in the presence of blood serum components.

[Isolation and characteristics of surface proteins from Streptococcus group A]. / Vydelenie i kharakteristika poverkhnostnykh belkov streptokokka gruppy A.

Cell wall surface proteins of group A Streptococcus type 29 were extracted with 1 M hydroxylamine pH 6.0. The purification procedure included fractionation with ammonium sulfate and gel filtration on Sephadex G-150. SDS polyacrylamide gel electrophoresis revealed a number of proteins (approximately 20) with molecular mass of 70 kD; the difference in Mr between the proteins was 5-10 kD. Isoelectrofocusing demonstrated that the proteins are either acid (pI = 3.7) or weakly alkaline (pI = 7.7). Possible reasons for the heterogeneity of Streptococcus cell wall surface proteins are discussed.

[Changes in the cell wall composition and structure of Streptococcus pyogenes during batch culture]. / Izmenenie sostava i struktury kletochnykh stenok Streptococcus pyogenes pri periodicheskom kul'tivirovanii.

Changes in S. pyogenes cells in the process of batch cultivation have been studied. The composition of S. pyogenes cell walls has been studied by amino acid analysis; besides, their resistance to enzymatic hydrolysis and the electric conductivity of cell-wall lysates have been determined at different phases of the growth of S. pyogenes. The molar amino acid composition, expressed in percent, is unrelated to the growth phase, while the content of amino acids in preparations changes in the process of growth and reaches its maximum in the middle and in the end of the logarithmic phase. At the same time the electric conductivity of cell-wall lysates reaches the minimum level at these growth stages. The authors suggest that additional electrically charged compositions are formed in the cell walls at the beginning of the logarithmic and stationary phases. A considerable increase in the initial rate of cell-wall lysis with muramidase has been found to occur at the end of the logarithmic phase. This difference in the initial rate in the initial rates of lysis of S. pyogenes cell walls at different growth phases decreases after previous treatment of the cell walls with streptolytin possessing proteolytic activity. Analysis of these data leads to a conclusion on the "loose" structure of the outer protein layer of the cell wall at the end of the logarithmic phase of the growth curve.

[Comparative study of lipoteichoic acid from Streptococcus pyogenes type 29 isolated by different methods]. / Sravnitel'noe izuchenie lipoteikhoevoi kisloty Streptococcus pyogenes tip 29, vydelennoi razlichnymi sposobami.

A comparative study of lipoteichoic acid preparations extracted from Streptococcus pyogenes with cold and hot phenol and trichloracetic acid was made. The most delicate way for isolation of lipoteichoic acid from the given microorganisms is cold phenol extraction.

[Quantitative determination of the protein and carbohydrate polymers in the cell wall of Streptococcus group A]. / Kolichetsvennoe opredelenie belkovykh i uglevodnykh polimerov kletochnoi stenki Streptococcus gruppy A.

The content of protein and carbohydrate polymers was estimated in the cell wall of Streptococcus, group A, type 29. A method was developed for analysing peptidoglycane in a polysaccharide-peptidoglycane complex after the prior oxidation by sodium periodate. It was found that the cell wall peptidoglycane bears two carbohydrate and three amino acid residues, i. e. N-acetylglucosamin, muramic acid, glutamic acid, alanine and lysine, in the ratio 1:1:1:4:1, respectively. The data on the cell wall composition prior to and after its oxidation with sodium periodate are given, and the ratio between the main structural components is determined: proteins (60% mol), polysaccharide (23% mol), peptidoglycane (17% mol).

[Determination of cell wall amino sugars in Streptococcus on a carbohydrate analyzer]. / Opredelenie aminosakharov kletochnoi stenki streptokokka na uglevodnom analizatore.

A method of determining aminosaccharides (muramic acid, glucosamine and galactosamine) by means of a carbohydrate analyzer "Biotronic" using the cation-exchange resin DC-6 A ("Durrum") was developed. Chromatographic conditions correspond to the conditions of neutral sugar analysis on a column with DCh-4 resin, that enables after a slight modification of the analyzer to pass from the determining of aminosaccharides to the determining of neutral sugars. The method was used for determining the carbohydrate composition of streptococcus cell walls. The results obtained allow to conclude that using this method one can get more information on the hydrocarbon composition of various biological objects than using the method of aminosaccharide determining by means of aminoacid anylyzer, which is widely in practice nowadays.

[Isolation and characterization of endo-N-acetylmuramidase produced by Actinomyces levoris]. / Vydelenie i kharakteristika endo-n-atsetil-muramidazy, podutsiruemoi Actinomyces Levoris.

Precipitation by ammonium sulfate and a subsequent purification of the culture fluid of Actinomyces levoris by gel-filtration through Sephadex G-25, ion-exchange chromatography on DEAE-cellulose and CM-cellulose resulted in an enzyme which activley lyzes the cell walls of a hemolytic streptococcus of group A. The molecular weight (12,500), isoelectric point (pI 10,6) and amino acid composition of the enzyme were determined. The enzyme specificity was assayed using peptidoglycane isolated rom the cell walls of streptococcus of group A used as a substrate. An analysis of the hydrolysis products of peptidoglycane showed that the enzyme under study is an endo-beta-N-acetylmuramidase (EC 3.2.1.17).