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Z F Shmakova

Publications and source records attributed to Z F Shmakova.

9 recordsLinked to original sources
PubMed1991

[Immunological study of lysates from the cell wall of group A Streptococcus].

The chemical composition and presence of immunogenic components in the lysates of the cell walls of group A Streptococcus, type M29, were studied. The lysates were prepared with the use of muramidase. Fc-Receptors were detected in the lysates. Within the first 30 minutes of cell wall lysis by muramidase, 4 times higher amounts of the protein reacting with fibrinogen excreted than in the subsequent 4 hours. The lysates contained immunogenic proteins. Fraction III isolated by chromatography of the 30-minute lysate on DEAE-trisacryl formed a single precipitation band with lysate antiserum. The lysate Fraction IV forming three precipitation bands contained a protein not specific of the type. The protein was identical to the protein antigen from Triton X-100 extracts of group A Streptococcus, types M1, M12 and M29. The group-specific polysaccharide was detected in the lysate Fraction I and Fraction II of the 4-hour lysate.

Bacterial Proteins↗
PubMed1990

[The physicochemical and biochemical characteristics of the cell walls in M+ and M- variants of Streptococcus group A type 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.

Amino Acids↗
PubMed1989

[The effect of blood serum components on the growth, biochemical and biological properties of streptococcus].

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.

Amino Acids↗
PubMed1989

[Comparative study of cell walls of group A Streptococcus and its non-adhesive phosphomycin-resistant mutant].

The cell wall composition of nonadhesive fosfomycin-resistant mutant of group A streptococcus and highly adhesive wild strain have been studied. The cell wall of the mutant nonadhesive strain contained significantly reduced amounts of lipoteichoic acid and surface proteins as compared to the wild strain, did not contain surface lipoteichoic acid, and, possibly, differed in peptidoglycan-polysaccharide bonding. No differences in the qualitative carbohydrate composition of the cell walls were found. The amino acid composition of the cell walls of these microorganisms differed only in alanine content, which correlates with the reduction of lipoteichoic acid content in the mutant strain. The structural similarity of peptidoglycans of the two strains is demonstrated.

Amino Acids↗
PubMed1989

[Study of the composition of cell wall of group A Streptococcus after hydrolysis using muramidase from Streptomyces levoris].

The aim of the experiment was to study the lysis products of cell walls of group A streptococci resulting from exposure to N-acetylmuramidase. It was shown that for isolating surface proteins free of polysaccharide and peptidoglycan fragments it was necessary to treat the streptococcal cell walls with endo-beta-N-acetylmuramidase for no more than 30 minutes. Prolonged hydrolysis with muramidase led to the presence of polysaccharide and the peptidoglycan fragments in the protein fractions, intracellular wall proteins covalently bound to the peptidoglycan fragments and polysaccharide being also released.

Bacterial Proteins↗
PubMed1978

[Lysis of the cellular walls of Streptococcus group A by enzymes produced by actinomycetes].

More than 80 cultures of actinomycetes belonging to different taxanomic groups were studied with a purpose of screening actinomycetes actively producing enzymes lyzing the cell walls of group A streptococci. 31 strains of the actinomycetes producing enzymes which lyzed the cell walls by 20-50 and 60-80 per cent within 1 and 4 hours respectively were selected. The proteolytic activity of the enzymes produced by these strains was also studied. It was shown that 4 cultures, i.e. Actinomyces albus, strains 6 and 9, Actinomyces levoris, strain 29 and Actinomyces gibsonii, strain 42 were of interest as organisms producing enzymes which lyzed the streptococcal cell wall without impairing its antigenic components.

Actinomycetales↗
PubMedDate not supplied

[Lytic enzymes produced by Actinomyces levoris].

The composition of the enzyme complex produced by Actinomyces levoris which exhibits lytic action on the cell walls of Streptococcus lactis was studied by gel filtration on Sephadex G-25, ion exchange chromatography and isoelectric focusing. The complex was found to contain at least seven enzymes having different isoelectric points and substrate specificity. The enzymes were divided into three groups. (1) The enzyme with pI 10.2 seems to be a specific glucosidase; it possesses a high activity of the cell wall lysis and lacks a proteolytic activity. (2) The enzymes with pI 9.2 and 9.0 are, apparently, specific lytic proteases; they display both lytic and proteolytic activities. (3) The enzymes with pI 10.0, 9.5, 5.7 and 4.2 are, presumably, non-specific lytic proteases; they have a low lytic activity and a high proteolytic activity.

Bacteriolysis↗