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PubMed1976

[The immunobiology of M-proteins of Streptococcus pyogenes. I. Isolation and purification of M-proteins from group A streptococci (Streptococcus pyogenes) type 1].

Streptococci of group A, type 1, are lysed by use of phage associated lysin, which is characterized as a N-Acetyl-D-glucosaminidase. This enzyme has no proteolytic activity. Type specific protein antigens are isolated and purified by ion exchange chromatography on CM-cellulose and DEAE-cellulose of the crude extract, concentrated by precipitation with ammonium sulfate. The immunization tests are carried out on monkeys and rabbits.

Animals↗
PubMed1978

Interaction between erythromycin and lincomycin in Streptococcus pyogenes.

Ten strains of Streptococcus pyogenes isolated were moderately resistant to erythromycin and highly but paradoxically resistant to lincomycin, and they showed antagonism between the two antibiotics. Another strain was moderately resistant to erythromycin and sensitive to lincomycin, and it showed synergism between the two antibodies.

Dose-Response Relationship, Drug↗
PubMed1979

Immunoelectron microscopic localization of T proteins in the cell wall of Streptococcus pyogenes.

T proteins of Streptococcus pyogenes (group A streptococci) were localized by means of immunochromatographical isolated anti-T-antibodies. For the electron microscopical detection both the direct and the indirect immunoferritin techniques were used. The arrangement of the ferritin particles showed, that the T proteins are evenly distributed on the whole cell surface. They are immediately bound to the outer layer of the cell wall or to only short filaments. On isolated cell walls the T protein was detected only on the outer surface.

Agglutination Tests↗
PubMed1977

Drug resistance in Streptococcus pyogenes isolated in Japan.

Drug resistance of Streptococcus pyogenes strains isolated during 1974 and 1975 in various districts in Japan were surveyed and compared with an earlier survey of 1970 to 1973. Of 1,021 strains, tetracycline-, macrolide antibiotic-, lincomycin-, and chloramphenicol-resistant strains were demonstrated at frequencies of 80.3, 62.3, 60.8, and 57.9%, respectively. Distinct group resistances to penicillin and aminoglycoside antibiotics could not be identified among the strains examined. It was characteristic that quadruple and triple resistances were manifested among the strains resistant to macrolide antibiotics, lincomycin, tetracycline, and chloramphenicol, and they were confined to the T-type 12. The emergence of multiply resistant streptococcal strains was due mostly to the rapid increase in isolation frequency of macrolide antibiotic- or macrolide antibiotics-lincomycin-resistant strains.

Anti-Bacterial Agents↗
PubMed1979

Chemical analysis of changes in membrane composition during growth of Streptococcus pyogenes.

Changes in the structural components of the Streptococcus pyogenes membrane between exponential and early stationary phases of growth are reported. The overall protein composition ranged from 70 to 73% of the dry weight of the membranes, irrespective of the phase of growth from which they were isolated. Amino acid analyses of membranes isolated from streptococci in either the exponential or stationary phase of growth demonstrated that two amino acids, cysteine and tryptophan, were absent. Further analysis of the membrane proteins by sodium dodecyl sulfate-polyacrylamide gradient gel electrophoresis demonstrated that there were proteins unique to a particular phase of growth as well as differences in the amount of specific proteins from the various growth phases. In addition, membranes isolated from exponential-phase cultures contained a higher percentage of peripheral protein than did stationary-phase membranes. There also appeared to be an increase in the amount of outer surface proteins during this growth phase. The phosphorus content of the membranes increased during the stationary phase of growth, whereas the sugar composition remained constant. The only sugar found under various conditions of growth in any of the strains was glucose. Total fatty acid content and the mole percent composition of various fatty acids did not change in the different phases of growth. However, the mole percent composition of fatty acids in the membranes of various group A streptococci did differ between strains. Therefore, these results provide evidence that the composition of membranes of S. pyogenes does not remain constant throughout the growth phases of the culture.

Adenosine Triphosphatases↗
PubMed1978

The cervical lymph nodes in Streptococcus pyogenes, group A, type 50, infection in mice.

Streptococcus pyogenes, group A, type 50, one of the few group A streptococcal types naturally occuring in mice, proved highly virulent in this species after experimental infection. Intranasal infection of 96 mice (Swiss albino, NMRI, and CBA) with this microorganism induced profound reactions in the cervical lymph nodes of 69% of the animals. Histologically, two different forms of reaction were distinguishable. In 61 mice, the lymph nodes exhibited follicular and lymphoplasmacellular hyperplasia and in 9 animals suppurative lymphadenitis was present. The ability of type 50 streptococci to persist in the pharynx of mice, and the similarity of the morphological changes induced by this organism appear to make intranasal murine group A, type 50, streptococcal infection a suitable model for human streptococcal pharyngitis.

Animals↗
PubMed1979

The role of M protein in phagocytosis. I. Activity of some enzymes in phagocytic cells during infection with Streptococcus pyogenes in vivo.

The phagocytosis of two type 12 Streptococcus pyogenes strains differing in M protein presence was investigated in vivo. The rate of phagocytosis and the streptococcal viability in phagocytic cells and outside of them was studied simultanously with estimation of enzymatic activity in phagocytic cells. It was observed that M positive strain was phagocytized at lower rate and also exhibited longer viability. Decrease of lactic dehydrogenase and ATP-ase activity in phagocytes of rabbits infected with M+ strain was also detected. These results suggest that M protein disturbs phagocytosis by inhibiting their main metabolic pathway of glycolysis.

Acid Phosphatase↗
PubMed1976

Defective synthesis of lipid intermediates for peptidoglycan formation in a stabilized L-form of Streptococcus pyogenes.

Membrane preparations obtained from a stabilized L-form of Streptococcus pyogenes are incapable of synthesizing peptidoglycan from uridine-5'-diphospho-N-acetyl-D-muramyl-L-Ala-D-iso-Glu-L-Lys-D-Ala-D-Ala and uridine-5'-diphospho-N-acetyl-D-glucosamine, in contrast with similar preparations from the parental streptococcus. Furthermore, 50-fold higher levels of lipid intermediates which serve as membrane-bound substrates for peptidoglycan synthesis are synthesized in reaction mixtures containing streptococcal membranes than with similar preparations from the L-form. These observations suggest that the inability of this stabilized L-form to form a cell wall in vivo lies, at least in part, in its failure to synthesize significant quantities of the lipid substrates for peptidoglycan synthesis.

Adenosine Triphosphate↗
PubMed1978

Hemolytic mutants of group A Streptococcus pyogenes.

Hemolytic mutants of Lancefield strain SS-95 and ATCC 19615 Streptococcus pyogenes were produced by treatment with N-methyl-N'-nitro-N-nitrosoguanidine. These mutants contained the same levels of streptolysin O, nicotinamide adenine dinucleotidase, deoxyribonuclease, and hyaluronidase. The mutants were deficient in streptolysin S, as was the naturally occurring nonhemolytic Lowry strain. The mutants retained their pathogenicity for mice and, when reisolated from the dead animals, produced the mutant hemolytic pattern.

Animals↗
PubMed2025

Temporal and geographical lineage dynamics of invasive Streptococcus pyogenes in Australia from 2011 to 2023: a retrospective, multicentre, clinical and genomic epidemiology study.

BACKGROUND: Defining the temporal dynamics of invasive Streptococcus pyogenes (group A Streptococcus) and differences between hyperendemic and lower-incidence regions provides crucial insights into pathogen evolution and, in turn, informs preventive measures. We aimed to examine the clinical and temporal lineage dynamics of S pyogenes across different disease settings in Australia to improve understanding of drivers of pathogen diversity. METHODS: In this retrospective, multicentre, clinical and genomic epidemiology study, we identified cases of invasive S pyogenes infection from normally sterile sites between Jan 1, 2011, and Feb 28, 2023. Data were collected from five hospital networks across low-incidence regions in temperate southeast Australia and the hyperendemic, tropical, and largely remote Top End of the Northern Territory of Australia. The crude incidence rate ratio (IRR) of bloodstream S pyogenes infection comparing the Top End and southeast Australia and in First Nations people compared with non-First Nations people was estimated by quasi-Poisson regression. We estimated odds ratios (ORs) of intensive care unit (ICU) admission, in-hospital mortality, and 30-day mortality for the Top End versus southeast Australia using logistic regression. Retrieved and successfully sequenced isolates were assigned lineages at whole-genome resolution. Temporal trends in the composition of co-circulating lineages were compared between the two regions. We used an S pyogenes-specific multistrain simulated transmission model to examine the relationship between host population-specific parameters and observed pathogen lineage dynamics. The prevalence of accessory genes (those present in 5-95% of all genomes) was compared across geographies and temporal periods to investigate genomic drivers of diversity. FINDINGS: We identified 500 cases of invasive S pyogenes infection in patients in the Top End and 495 cases in patients in southeast Australia. The crude IRR of bloodstream infection for the Top End compared with southeast Australia was 5·97 (95% CI 4·61-7·73) across the entire study period; in the Top End, infection disproportionately affected First Nations people compared with non-First Nations people (5·41, 4·28-6·89). The odds of in-hospital mortality (OR 0·43, 95% CI 0·26-0·70), 30-day mortality (0·38, 0·23-0·63), and ICU admission (0·42, 0·30-0·59) were lower in the Top End than in southeast Australia. Longitudinal lineage analysis of 642 S pyogenes genomes identified waves of replacement with distinct lineages in the Top End, whereas southeast Australia had a small number of dominant lineages that persisted and cycled in frequency. The transmission model qualitatively reproduced a similar pattern of replacement with distinct lineages when using a high transmission rate, small population size, and high levels of human movement-characteristics similar to those of communities in the hyperendemic Top End. Using a lower transmission rate, larger population size, and lower levels of migration similar to those of communities in urbanised southeast Australia, the transmission model qualitatively reproduced a pattern of dominant lineages that cycled in frequency. Despite distinct circulating lineages, the prevalence of accessory genes in the bacterial population was maintained across geographies and temporal periods. INTERPRETATION: In a hyperendemic setting, the replacement of distinct S pyogenes lineages occurred in waves, which could be linked to the disproportionate burden of disease and sparse human population in this setting. The maintenance of bacterial gene frequency could be consistent with multilocus selection. These findings suggest that lineage-specific interventions-such as vaccines under development-should consider disease setting and, without broad cross-protection, might lead to lineage replacement. FUNDING: National Health and Medical Research Council, and Leducq Foundation.

Humans↗
PubMed1978

Isolation and characterization of a Streptococcus mutans bacteriocin inhibitor from Streptococcus pyogenes.

An inhibitor of Streptococcus mutans strain GS5 bacteriocin was released from a bacteriocin-sensitive strain of S. pyogenes by sonic treatment and partly purified by gel filtration on a Sepharose 6B column. The inhibitory factor was sensitive to heat, trypsin, and periodate and possessed a molecular weight of approximately 93,000. This factor may be the receptor for the S. mutans bacteriocin.

Bacterial Proteins↗
PubMed1976

Susceptibility of Staphylococcus aureus, Streptococcus pyogenes and Diplococcus pneumoniae to antibiotics. Comparison of patterns in Poland and Federal Republic of Germany.

One hundred and eighty five strains of Gram-positive cocci were tested for susceptibility to 16 antibiotics, including some newer drugs, by agar dilution technique. Of these, 100 strains (50 each isolated in Poland and Germany) were Staphylococcus aureus, 55 Streptococcus pyogenes, and 30 Diplococcus pneumoniae. Previous investigations of streptococci and pneumococci isolated in Poland and Federal Republic of Grmany, revealed no differences in antibiotic-susceptibility patterns in both countries, which was not the case with staphylococci. Present study demonstrates further evidence for existence of differences in antibiotic-sensitivity of staphylococci, depending of their geographical origin, and presents actual state of susceptibility to antibiotics of Streptococcus pyogenes and Diplococcus pneumoniae.

Anti-Bacterial Agents↗
PubMed1977

[Relationships between Streptococcus pyogenes T4-antigens and haptoglobin types (author's transl)].

Some strains of beta-haemolytic streptococci were agglutinated with high titers (1:200-1:6400) by human sera of the haptoglobin types 2-2 and 2-1. No agglutination or with low titers (up to 1:20) was observed with sera of the haptoglobin type 1-1. This reactivity depends from the contents of Streptococcus pyogenes T-antigens of the T-complex 4,24... This T4-antigen is present in group A streptococci (Strep. pyogenes) of the types 4, 24, 26, 28, 29, 46, 48 and 60 but it may be present also in some strains of streptococcal groups C and G. During a 10-year period we isolated 12 strains of Strep. equisimilis (group C) carrying the T-4 antigen (1.6%) and 50 group-G streptococci with T-4 antigen (6.4%) of all group G streptococci). These strains were agglutinated without an exception with high titers by Hp 2-2 and Hp 2-1 sera but not by sera of the haptoglobin type 1-1. The same particuliarity was shown by Streptococcus pyogenes types of the T-complex 4, 24... One strain of type 26 (BC 179) has no T antigen and therefore it was not agglutinated in the above mentioned manner. The phenomenon depends from the medium; it occurs after cultivation of the streptococci in Pope broth or in meat-infusion with glucose but not or only reduced in beef heart-proteose-medium. The agglutination reaction is caused by the haptoglobin but not by agglutinins against the T4-antigens.

Agglutination↗
PubMed1977

The isolation of Streptococcus pyogenes from throat swabs.

Simulated throat swabs were prepared with known numbers of Streptococcus pyogenes; some were suspended in pasteurised human saliva and an equal number in saline. Two types of commercially available swabs were tested; these were composed of (1) plain, buffered, cotton wool, and (2) albumen-coated cotton wool. The mean recovery rates of first platings on solid media from albumen-coated and plain cotton-wool swabs were similar (8-2% and 8-3%) and the mean recovery rates from platings 1-4 were also similar (6-6% and 6-5%). The greater the delay in plating, the less were the chances of recovery of streptococci, although the viability of these was significantly prolonged on swabs held at 4 degrees C. Similar results were again produced by both types of swabs; processing swabs in saliva, however, produced by both types of swabs; processing swabs in saliva, however, produced a recovery rate that was 1-2% greater than the rate for the saline series. Swabs were also agitated or squeezed by forceps in nutrient broth to release any organisms they contained, and standard samples of the broth were then plated on solid media. Counts thus obtained indicated that about 50% of the original inoculum was still viable and could be recovered from the broth; in comparison, recoveries from initial direct plating of the swabs were low. No demonstrable toxic effect was produced by the cotton wool in these experiments.

Albumins↗
PubMed1979

Quantitative immunoelectrophoretic analysis of Streptococcus pyogenes membrane.

The antigenic composition and molecular structure of the plasma membrane of Streptococcus pyogenes (group A; M type 6) were studied by crossed immunoelectrophoresis (XIE) and other related quantitative immunoelectrophoretic techniques. After establishment of a reference pattern of 29 immunoprecipitates, the relative differences in amounts of individual antigens contained in membranes isolated from cells that were harvested during the exponential or stationary phase of growth were examined. Relative increases and decreases in amounts of individual antigens were estimated from the areas subtended by immunoprecipitates after XIE of Triton X-100 extracts. The asymmetric distribution of antigens on the inner and outer surfaces of the membrane was established in absorption experiments with intact, stable protoplasts. Of the 29 immunoprecipitates, 8 appeared to contain antigens exposed on the outer surface of the membrane, whereas 11 appeared to contain antigens either located on the inner surface or unexposed. Six antigens appeared to have limited exposure on the outer surface, and four others remain to be assigned. Certain immunoprecipitates were characterized with respect to enzymatic activity or interaction with the lectin concanavalin A. Reduced nicotinamide adenine dinucleotide dehydrogenase (EC 1.6.99.3), adenosine triphosphatase (EC 3.6.1.3), and polynucleotide phosphorylase (EC 2.3.7.8) were demonstrated by zymogram techniques. The latter two activities were present within the same immunoprecipitate, suggesting the occurrence of a multienzyme complex. In addition, the areas under the immunoprecipitates containing the three enzymatic activities were not affected by absorption of antimembrane immunoglobulin with intact protoplasts and thus appeared to be located on the inner surface of the membrane. The results from absorption experiments also suggested that the exposure of outer protoplast surface antigens was greater on protoplasts from exponential-phase cells than on those from stationary-phase cells, even when found in increased amounts in the latter.

Adenosine Triphosphatases↗
PubMed1979

Immunofluorescent and immunoelectron microscopic demonstration of primate heart muscle antigens cross-reactive with Streptococcus pyogenes.

The presence of antigens in heart muscles cross-reactive with antibodies against Streptococcus pyogenes were examined in heart samples of seven primate species (chimpanzee, rhesus macaque, stump-tailed macaque, hamadryas baboon, capuchin monkey, green monkey and patas monkey). Cross-reactive antigens were localized by means of the indirect immunofluorescent technique in nearly all samples tested. The fluorescence pattern was the same as found in the heart muscle of other mammals. Using the indirect immunoferritin technique the substructural distribution of the antigens was investigated in heart muscle of rhesus macaque and hamadryas baboon. Beside the location on the cell surface the antigens were also demonstrated within the cell. Above all there was a strong labelling along the intercalated discs and in the sarcoplasmatic reticulum.

Animals↗
PubMed1978

Transfer of erythromycin resistance from clinically isolated lysogenic strains of Streptococcus pyogenes via their endogenous phage.

Endogenous bacteriophage from clinically isolated, erythromycin-resistant strains of Streptococcus pyogenes, upon induction by treatment with mitomycin C, were demonstrated to cause transduction of antibiotic resistance yielding transductants resistant to relatively high concentrations of erythromycin. Transduction of resistance to erythromycin via endogenous phage may play a significant role in the emergence of streptococci with multiple resistance in the clinical environment.

Bacteriophages↗
PubMed2025

The Streptococcus pyogenes mannose phosphotransferase system (Man-PTS) influences antimicrobial activity and niche-specific nasopharyngeal infection.

Streptococcus pyogenes is a human-adapted pathogen that can cause multiple diseases, including pharyngitis and skin infections. Although this bacterium produces many virulence factors, how S. pyogenes competes with the host microbiota is not well understood. Here, we detected antimicrobial activity from S. pyogenes MGAS8232 that prevented the growth of Micrococcus luteus. This activity was produced when cells were grown in 5% CO2 in M17 media supplemented with galactose; however, the addition of alternative sugars coupled with genome sequencing experiments revealed that the antimicrobial phenotype was not related to classical bacteriocins. To further determine genes involved in the production of this activity, a transposon mutant library in S. pyogenes MGAS8232 identified the mannose phosphotransferase system (Man-PTS), a major sugar transporter, as important for the antimicrobial phenotype. Loss-of-function transposon mutants linked to the antimicrobial activity were identified to also be involved in alternative sugar utilization, and additionally, the Man-PTS was further identified from an inadvertent secondary mutation in a bacteriocin operon mutant. Sugar utilization in the Man-PTS mutants demonstrated that galactose, mannose, and N-acetylglucosamine utilization was impaired. RNA-seq experiments in high and low glucose concentrations further characterized the Man-PTS as a glucose transporter; however, transcriptional regulators or virulence factors were not affected with the loss of the Man-PTS. Deletion of Man-PTS demonstrated defects in a mouse model of nasopharyngeal infection but not skin infection. This work suggests that the ability of S. pyogenes to utilize alternative sugars presented by glycans may play a role in acute infection and interactions with the endogenous microbial population existing in the nasopharynx.IMPORTANCEStreptococcus pyogenes is responsible for over 500,000 deaths per year primarily due to invasive infections and post-infection sequelae, although the most common manifestations include pharyngitis and impetigo. S. pyogenes can adapt to its environment through alternative sugar metabolism. Here, we identified an antimicrobial phenotype that was not bacteriocin-related but a by-product of alternative sugar metabolism. The mannose phosphotransferase system was involved in the production of the antimicrobial and was also important for S. pyogenes to utilize alternative sugars and establish nasopharyngeal infection but not skin infection. Overall, this study identified potential strategies used by S. pyogenes for interactions with the endogenous microbiota and further elucidated the importance of sugar metabolism in acute upper respiratory tract infection.

Streptococcus pyogenes↗