PubMed Health⌕ Search

Biomedical subjects

E P Savel'ev

Publications and source records attributed to E P Savel'ev.

At least 19 recordsLinked to original sources
PubMed1995

Antigenic determinants of Streptococcus pyogenes ribosomes.

An attempt has been made to identify the ribosomal proteins responsible for the production of antibodies upon immunization of monkeys with 70S ribosomes of Streptococcus pyogenes group A 29 M type. Identification was carried out by immunoblotting after isolation and separation of the proteins of 70S, 50S and 30S ribosomal particles on one- and two-dimensional gel electrophoresis. Three major proteins of S. pyogenes 70S ribosomes with clearly expressed antigenic properties were identified by Western blotting. One of these proteins belonged to the 50S subunit and the other two--to the 30S ribosomal subunit. We assume that these proteins represent those of group A streptococci. As a result the antibodies are produced first of all against these antigenic proteins in contrast to the others evolutionary conservative ribosomal proteins.

Animals↗
PubMed1991

Molecular-biological and immunological properties of ribosomal vaccines.

Data on the immunological properties and protective action of ribosomal vaccines are reviewed from the point of view of the structural and functional properties of ribosomes. Comparative analyses are presented for ribosomes from Gram-negative and Gram-positive microorganisms, and for ribosomes from prokaryotes and eukaryotes. Special consideration is given to the nature of the protective factors of ribosomal preparations and the mechanisms of ribosomal vaccine immunogenesis.

Animals↗
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↗
PubMed1987

[Isolation and characteristics of surface proteins from Streptococcus group 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.

Amino Acids↗
PubMed1986

[Immunochemical analysis in research on antibodies to Streptococcus group A ribosomes].

The use of the competitive enzyme immunoassay (EIA) has made it possible to demonstrate that antiserum to the ribosomes of group A streptococcus, type 29 M, contains antibodies to homologous protein M and does not contain antibodies to group A polysaccharide, lipoteichoic acid and peptidoglycan. Ribosomal antiserum has been found to bind with the surface of heterologous type M streptococci in EIA, while forming no precipitation lines with heterologous proteins M in the double immunodiffusion test, which indicates that the binding of ribosomal antibodies with the surface of group A streptococcal cells is not type-specific. Antibodies to the ribosomes of group A streptococcus recognize some of the antigenic determinants of E. coli ribosomes.

Animals↗
PubMed1986

[Determination of antibodies against ribosomes and various cell wall components and detection of circulating antigens of group A Streptococcus in patients with erysipelas].

The level of antibodies to the ribosomes, polysaccharide A and peptidoglycan of group A streptococcus in the blood of patients with primary, secondary, and often relapsing erysipelas was studied by means of the enzyme immunoassay with the use of the sandwich techniques. For control, the sera of healthy donors were used. In the sera obtained from all groups of erysipelas patients a significant rise in the levels of antibodies to ribosomes and peptidoglycan in comparison with the controls was revealed. An increase in the level of antibodies to polysaccharide A was revealed only in patients with frequently relapsing and secondary erysipelas. Depending on the clinical form and the duration of the disease, polysaccharide A was detected in 32-51.9% of erysipelas patients and protein-ribosomal antigen was detected in 28.6-51.9% of such patients.

Antigens, Bacterial↗
PubMed1982

[Sequential isolation of the structural components of the cell wall of Streptococcus group A].

The scheme of the consecutive isolation of cell-wall components from group A streptococci, type 29, has been developed. Extraction by means of 1 M hydroxylamine buffer with pH 6.0 (stage 1) and 10.0 (stage II) has yielded proteins showing different behavior in the double immunodiffusion test in agar. The protein obtained at pH 6.0 has given cross reaction with antiserum to type 1, while the protein obtained at pH 10.0 has been found to react only with homologous serum to type 29. Extraction with 10% trichloroacetic acid at 4 degrees C (stage III) and 5% trichloroacetic acid (stage IV) has resulted in obtaining, respectively, polysaccharide forming one line with group-specific antiserum to group A in the double immunodiffusion test and polysaccharide having no such activity. At the last stages the HCl extract of the cell-wall residue (stage V) and peptidoglycan (stage VI) have been obtained.

Bacterial Proteins↗
PubMed1982

[Isolation and evaluation of properties of muramidase causing the lysis of group A streptococci].

Muramidase which actively lyses the cell walls of group A hemolytic streptococci has been isolated from the culture fluid of Actinomyces levoris by precipitation on ammonium sulfate, gel filtration on Sephadex G-25, ion exchange chromatography on DEAE cellulose and double electrofocusing. The enzyme thus obtained has shown its maximum activity at 40-50 degrees C. At 60 degrees C muramidase was completely inactivated. The enzyme has a wide range of optimum pH values: 5.0-9.5. The highest percentage of lysis of streptococcal cell walls has been observed in plycine-NaOH and potassium phosphate buffers at pH 8.0. Muramidase completely lysed Streptococcus pyogenes cells of different serological groups except enterococci (group D) and staphylococci. This sign allows to differentiate group D streptococcus from streptococci of other groups.

Actinomyces↗
PubMed1980

[Isolation and characterization of endo-N-acetylmuramidase produced by 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).

Actinomyces↗
PubMed1978

[Autolysis of hemolytic streptococcus group A].

As revealed, autolytic enzymatic system of hemolytic streptococcus, group A, expressed the maximal activity at the end of the exponential growth phase. Autolysis was accompanied by the release of N-acetylaminosugars and of free amino group. Optimal conditions for the lytic system function were chosen (composition, ionic strength, and buffer pH). The activating action of trypsin and chemotrypsin was demonstrated.

Bacteriolysis↗
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

[Lysis of the cell walls of streptococcus group A by Streptomyces griseus pronase].

The effect of Streptomyces griseus pronase on Streptococcus group A cell walls was studied. Cell walls were shown to be lysed by pronase, the lysis level being dependent on the molarity of the potassium-phosphate buffer used. With an increase in the buffer molarity from 0.005 M to 0.05 M lysis of cell walls decreased from 70-80% to 30%. By DEAE-cellulose chromatography lysates were separated into two fractions the first of which contained a group specific polysaccharide. A preparative method of obtaining a group specific polysaccharide of Streptococcus group A using Streptomyces griseus pronase under mild conditions is described.

Antigens, Bacterial↗