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PubMed1984

Small DNA deletions creating avirulence in Streptococcus pyogenes.

The M protein is the antigen on the surface of group A streptococci that allows these bacteria to resist phagocytosis. DNA encoding the M12 protein was cloned into Escherichia coli and used as an isotopically labeled hybridization probe to compare genomic DNA's isolated from M+ and M- isogenic cultures in an effort to elucidate the genetic basis of this variation. DNA's from two spontaneous, independent M- variants contained small (approximately 50 base pairs) deletions which were mapped to identical restriction fragments within or adjacent to the M protein coding sequence. Taken together with the pleiotropic nature of these deletions, this suggests that they define a regulatory switch.

Antigens, Bacterial↗

PubMed1974

Sensitivity of Streptococcus pyogenes to sulphamethoxazole, trimethoprim, and cotrimoxazole.

When tested on Wellcotest (sensitivity test agar, Wellcome) supplemented with lysed horse blood, 59 clinical isolates of beta-haemolytic streptococci, belonging to several serological groups, are all sensitive to sulphamethoxazole, to trimethoprim, and to cotrimoxazole. The results obtained on diagnostic sensitivity test agar (Oxoid) containing lysed horse blood are comparable. When Mueller Hinton agar (Difco) is used, some of these strains are called resistant: this is especially true in the case of sulphamethoxazole.Furthermore, on Mueller Hinton agar, even supplemented with lysed blood, discrepancies between diameters of inhibition zone and MIC values exist for the three drugs tested, strains with a low MIC being considered resistant by the disc method. Such disagreements are not observed with non-streptococcal control strains.

Animals↗

PubMed1983

Insertional inactivation of streptolysin S expression in Streptococcus pyogenes.

The inactivation of a genetic determinant critical for streptolysin S production was accomplished by transfer and insertion of the transposon Tn916 into the DNA of a group A streptococcal strain. The group D strain CG110 was able to efficiently transfer Tn916 into the group A strain CS91 when donor and recipient cells were concentrated and incubated together on membrane filters. Among tetracycline-resistant transconjugants, nonhemolytic mutants that no longer produced streptolysin S and retained the capacity to produce streptolysin O were discovered. Hemolytic revertants from these mutants regained tetracycline sensitivity; other revertants still retained a tetracycline resistance phenotype. Hybridization studies employing Tn916 DNA located Tn916 sequences in EcoRI and HindIII fragments of DNA from mutants devoid of streptolysin S; one carried a single copy of Tn916, and the other two carried multiple copies of the transposon.

Bacterial Proteins↗

PubMedDate not supplied

[In vitro bactericidal action of a complex of natural cytokins on Streptococcus pyogenes].

The data on the antimicrobial in vitro action of a complex of natural cytokins (CNC)--the substance and the preparation "Superlymph"--on virulent museum and clinical macrolid-resistant group A beta-hemolytic streptococci, are presented. CNC suppressed the growth of museum test culture of streptococci in the concentration dependent manner. Moreover, the preparation "Superlymph" proved to be an effective antistreptococcal remedy in its action on erythromycin-resistant group A streptococcal (GAS) strains. The substance of the preparation induced the lysis of GAS cells, grown on lawn plates and in the system of spectrophotometric analysis. The effect thus established could be caused by cationic antimicrobial peptides (protegrins), contained in "Superlymph".

Anti-Bacterial Agents↗

PubMed1980

Purification and characterization of erythrogenic toxins. II. Communication: in vivo biological activities of erythrogenic toxin produced by streptococcus pyogenes strain ny-5.

Some in vivo biological activities of a purified erythrogenic toxin preparation from strain NY-5 of group A streptococci (ET NY-5) were studied. After intracutaneous administration in a dose of minimally 5 X 10(-8) mg, the toxin provoked a skin reaction in old guinea pigs. No skin reaction could be elicited in young adult rabbits. ET NY-5 was pyrogenic for rabbits; the MPD-4 amounted to 0.017 microgram/kg intravenously. The pyretic response had a delayed onset and then rose gradually up to hour 5 postinjection. Intravenous administration led to changes in circulating leukocyte counts, viz. brisk acute granulocytopenia and protracted lymphopenia. The method of pyrogenic cross tolerance revealed that ET NY-5 contains two types of pyrogenic exotoxin, A and C.

Animals↗

PubMed1995

A single emm gene-specific oligonucleotide probe does not recognise all members of the Streptococcus pyogenes M type 1.

Serological typing of the streptococcal M protein has recently been challenged by a number of unique molecular methodologies based on oligonucleotide recognition of allelic variations within the M protein (emm) gene. In these methods, stringent hybridization of an oligonucleotide probe to a polymerase chain reaction amplified emm gene is used as confirmation of specific M type identity. A sample of 17 isolates from 7 previously defined distinct genotypes were tested using a single M1 oligonucleotide probe. Isolates from only three of the genotypes hybridized with the probe. The results demonstrate that a single emm-specific oligonucleotide probe can not identify all members of M type 1, as defined by conventional serotyping using polyclonal antisera.

Amino Acid Sequence↗

PubMed1995

Analysis of immunoglobulin G-binding-protein expression by invasive isolates of Streptococcus pyogenes.

Invasive group A streptococcal isolates collected as part of a Centers for Disease Control and Prevention surveillance study were analyzed for expression of immunoglobulin G (IgG)-binding proteins. Two IgG-binding phenotypes of group A isolates of the M1 serotype were identified. The first group expressed a surface protein that bound all four human IgG subclasses (type IIo) and was recognized by rabbit anti-serotype M1-specific antiserum but not by normal rabbit serum. The second group expressed an IgG-binding protein that was also recognized by the anti-serotype M1 antiserum but demonstrated significant nonimmune reactivity only with human IgG3 (type IIb). Analysis of extracts of the isolates for reactivity with human IgA, fibrinogen, and albumin was also performed. The importance of the binding of human plasma proteins to pathogenic group A streptococci remains to be established.

Antigens, Bacterial↗

PubMed1977

[The occurrence of cross-reactive antigens in myocardial tissue and in streptococcus pyogenes. IV. Cytotoxic effect of lymphocytes sensitized in vivo to group A streptococci on primary cultures of heart muscle cells (author's transl)].

The cytotoxic effect of rat lymphocytes in vivo sensitized to group A streptococci, rat heart tissue or streptococcal M proteins was investigated in primary cultures of beating rat heart cells. Cytotoxicity was found in 75 to 82% of heart cell cultures in contact with lymphocytes sensitized to streptococcal whole cells or lysates and in 100% of those exposed to lymphocytes sensitized to rat heart tissue. Lymphocytes sensitized to M protein exert a cytopathic effect only in 8 and 12% cultures, respectively, and to a much more limited extent. Controls were affected in 6%. The cytotoxicity test seems to be useful to examine the presence of cross-reactive antigens within streptococcal vaccines.

Animals↗

PubMed1968

The serum opacity reaction of Streptococcus pyogenes. The demonstration of multiple, strain-specific lipoproteinase antigens.

Investigation into the antigenicity of streptococcal lipoproteinase has revealed the existence of multiple, immunologically distinct enzymes. Each lipoproteinase identified was found to be strain specific in that it was found only in strains of a particular T-agglutination pattern. In some T patterns, all streptococci of that T pattern which were examined shared a common lipoproteinase antigen. In other T patterns, strains which produced antigenically different lipoproteinases were identified. Evidence that the lipoproteinase antigen is distinct from other well-established cellular antigens of Group A streptococci has been presented. The production of this strain-specific enzyme by strains currently difficult to type by the standard M precipitin method may facilitate more precise identification of these strains and a better assessment of their role in the pathogenesis of Group A streptococcal infections and their sequelae.

Animals↗

PubMed2000

Distribution and antigenicity of fibronectin binding proteins (SfbI and SfbII) of Streptococcus pyogenes clinical isolates from the northern territory, Australia.

Fibronectin binding proteins play an important role in the adherence and invasion of group A streptococci (GAS). Genotypically distinct GAS isolates were screened for the presence and expression of two streptococcal fibronectin binding protein genes, sfbI and sfbII. Of the tested strains, 64 and 36% were shown to harbor and express the sfbI and sfbII genes, respectively. All sfbII-positive strains tested were also positive for sfbI, but only 28% of the sfbII-negative strains were positive for sfbI. High levels of immunoglobulin G antibodies to both SfbI and SfbII were found in sera from 80 subjects with defined streptococcal infections.

Adhesins, Bacterial↗

PubMed1985

Production of serum-opacity factor by Streptococcus pyogenes strains isolated from pharyngitis in children. Prevalence of "rheumatogenic" M types among OF-negative strains.

Two hundred ten S. pyogenes strains isolated in 1979, 1980 and 1984 from children with pharyngitis were here examined for properties which might be relevant to their rheumatogenic potential. Strains were first tested for the production of streptococcal serum-opacity factor and, among those scored as OF-negative, the presence was then verified of M types which have been epidemiologically related to rheumatic fever. Members of "rheumatogenic" M types are present among strains causing pharyngitis in children, which, however, also include a considerable proportion of OF-positive, probably non-rheumatogenic, strains. The results are discussed in the light of the low incidence of rheumatic fever in this country.

Child↗

PubMed2004

Vaccination with formalin-inactivated influenza vaccine protects mice against lethal influenza Streptococcus pyogenes superinfection.

Intranasal infection with non-lethal influenza A virus (IAV) followed by infection with group A streptococci (GAS) induces invasive, lethal GAS infections, including necrotizing fasciitis, in mice. We demonstrate that subcutaneous immunization of formalin-inactivated IAV vaccine or intranasal immunization of IAV vaccine and cholera toxin protected more than 75% of mice from death by lethal IAV-GAS superinfection. The increased survival rate correlates with increase in IAV neutralizing activity and the levels of serum anti-IAV IgG. Moreover, elimination of IAV from the lungs of vaccinated mice led to depletion of GAS associated with alveolar epithelial cells. These findings suggest that formalin-inactivated IAV vaccine may be useful for prevention of secondary bacterial infections following prior IAV exposure.

Administration, Intranasal↗

PubMed1997

Immunoglobulins inhibit adherence and internalization of Streptococcus pyogenes to human pharyngeal cells.

Purified human sIgA against group A streptococci inhibited streptococcal adherence to pharyngeal cells whereas rabbit serum raised against the whole M+ strain did not. Of note, inhibition of adherence by sIgA occurred despite a much lower immunreactivity against the M6 protein as compared to the hyperimmune serum against the whole M+ strain. The M protein does probably not mediate the adherence of group A streptococci to respiratory cells, as shown by previous studies. However, since the isogenic M- derivative was less invasive to human pharyngeal cells than the M+ strain, our invasion experiments suggest that the M protein may play a role in internalization of group A streptococci into eukaryotic cells. More importantly, internalization and not adherence could be blocked by rabbit serum immunized with recombinant M6 protein.

Animals↗

PubMed1983

Growth of Streptococcus pyogenes and streptolysin O production in complex and synthetic media.

A comparative study of the growth of a highly haemolytic group A streptococcal strain in Trypticase-yeast extract medium and in a chemically defined medium was undertaken. Appreciable growth was obtained in the latter medium with the release of significant amounts (120 haemolytic units) of streptolysin O. This indicates that toxinogenic factors present only in the peptones of complex media are not essential for biosynthesis and release of this cytolytic toxin, as is the case for many bacterial toxins. NADase was also released in the synthetic medium. Bacterial cell mass, growth rate, and streptolysin O production were threefold higher in the complex medium. The effects of various carbohydrates on streptolysin O production in complex medium are investigated. No repression of toxin formation by glucose was observed. The relationship between growth and toxinogenesis in streptococci and in other toxinogenic bacteria is discussed.

Culture Media↗

PubMed1987

Streptococcus pyogenes cell wall protein responsible for binding to pharyngeal epithelial cells.

The aim of this study was to identify a streptococcal cell wall substance which is able to bind to epithelial cells. The water-soluble phase of sonicated M+ and M- strains was incubated with pharyngeal and buccal epithelial cells. Electrophoretic analysis of these materials, before and after incubation, showed disappearance of one band from the M+ samples only, after incubation with pharyngeal epithelial cells. The specific anti-M protein serum did not precipitate this protein. Incubation of tested materials with buccal epithelial cells did not change their composition. The molecular mass of this band was estimated as 35,000 Daltons by the use of SDS-PAGE and marker proteins. These results suggest that an adhesin responsible for the streptococcal group A binding to pharyngeal epithelial cells is a protein closely associated with the M antigen.

Adhesins, Bacterial↗

PubMed1988

Type 1 and 3 M-proteins of Streptococcus pyogenes: peptic extraction and fibrinogen binding properties.

The pepsin extraction of group A type 1 streptococci for the isolation of M protein fragments was studied at different pH values and at different time intervals. The extracts were compared by SDS PAGE and fused rocket immunoelectrophoresis. Type 1 M protein fragments were prepared in preparative scale by pepsin extraction of type 1 streptococci at pH 5.5 for 60 min. The fragments were separated by affinity chromatography on immobilized fibrinogen and finally purified for sequence studies by gel chromatography. Pepsin extraction of group A type 3 streptococci was also studied at different pH values. In contrast to type 1, the SDS PAGE pattern changed drastically in dependence on the pH. Affinity chromatography on immobilized fibrinogen is also effective in the separation of the pH 5.5 type 3 streptococcal pepsin extract.

Antigens, Bacterial↗

PubMed1981

Interaction of streptococcal cell wall components with fibrinogen. I. adsorption of fibrinogen by immobilized T-proteins of streptococcus pyogenes.

Immobilized streptococcal T1-, T3- and T4-proteins to AH-Sepharose 4B were tested for their ability to absorb human fibrinogen. Purified fibrinogen and plasma samples were used for affinity chromatography. T1-protein was able to retain specifically fibrinogen from plasma. T4-protein bound fibrinogen in a similar manner, but it was not as specific as T1-protein. T3-protein failed to bind purified fibrinogen as well as fibrinogen from plasma. Adsorption of fibrinogen was accomplished using a 0.05 M phosphate/0.2 M NaCl/0.02% NaN3/pH 7.0 buffer system followed by elution with 0.05 M PO4/1 M NaCl/0.02% NaN3 to remove non specifically bound components. Retained components were eluted with 8 M Urea/0.025 M NaOAc, pH 5 and the fractions analyzed for fibrinogen content by SDS polyacrylamide gel electrophoresis. The presence of fibrinogen was determined by observations of the characteristic A alpha, B beta and gamma chain bands.

Adsorption↗

PubMed1982

Macrolide resistance in Streptococcus pyogenes and its correlation with T-type.

Erythromycin is accepted as the second drug of choice for streptococcal infections. The incidence of macrolide resistance in streptococcal strains has been low and the previously reported macrolide-resistant strains were almost all serotype T-12. In a 2-year survey conducted from 1979 to 1980, the strains isolated from a wide variety of geographic locations throughout Japan were studied for their macrolide-resistance. The resistance to erythromycin was correlated with the T-type of these strains and its minimum inhibitory concentrations were determined. Serotype T-12 strains isolated during this period were highly resistant to erythromycin. In addition, resistant strains were found in T-4 and T-1, the two other frequently isolated serotypes. Two point eight percent strains were moderately resistant with MICs of 1.56 to 12.5 microgram per ml and 25.5% of the strains were highly resistant with 100 microgram MIC or more.

Anti-Bacterial Agents↗