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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↗
PubMed2005

Is plasminogen deployed as a Streptococcus pyogenes virulence factor?

Streptococcus pyogenes (group A streptococcus) causes human skin and throat infections as well as highly invasive diseases including necrotizing fasciitis. Group A streptococcal infections and invasive disease have made a resurgence in developed countries during the past two decades. S. pyogenes use multiple pathways for the acquisition and activation of human plasminogen, securing potent proteolytic activity on the bacterial cell surface. Recent experimental evidence using a humanized transgenic mouse model suggests a crucial role for human plasminogen in the dissemination of S. pyogenes in vivo.

Plasminogen↗
PubMed2005

Acute glomerulonephritis associated with streptococcus pyogenes with concomitant spread of streptococcus constellatus in four rural families.

We studied history, renal histopathology and microbiology of an epidemic of acute glomerulonephritis associated with throat infections and uncommon culture results in four neighbour families. A 40-year-old man (index patient) was referred to a university hospital for dialysis and kidney biopsy due to a suspected acute glomerulonephritis. An acute tonsillitis had preceded the condition. Penicillin treatment had been started four days before the discovery of renal failure. Throat swabs were positive for beta-hemolytic streptococci, group C (GCS). GCS were also found in throat cultures from his wife and two of their children. The bacteria were typed as Streptococcus constellatus. A third child had S. constellatus expressing Lancefield antigen group G. A neighbour and two of his children fell ill the following week with renal involvement. Throat swabs from both these children were positive for S. constellatus. His third child had erythema multiforme and S. constellatus in the throat while a fourth child had beta-hemolytic streptococci group A; Streptococcus pyogenes. Kidney biopsies on the index patient and his neighbour showed an acute diffuse prolipherative glomerulonephritis compatible with acute post-streptococcal nephritis and microbiological analysis of renal tissue revealed in both cases S. pyogenes and S. constellatus. The families had had much contact and had consumed unpasteurized milk from our index patient's farm. In four of seven persons in two additional neighbouring families S. constellatus was found in throat swabs during the same month while two persons carried Streptococcus anginosus expressing the Lancefield C antigen. In conclusion spread of S. constellatus coincided with the occurrence of four cases of acute glomerulonephritis. The two biopsied patients had both S. pyogenes and S. constellatus present in renal tissue. The epidemic either suggested that the outbreak of glomerulonephritis was due to S. pyogenes but coincided with the transmission and colonization of S. constellatus or that the S. constellatus strains were highly pathogenic or nephritogenic and that this organism can be transmitted in such cases.

Acute Disease↗
PubMed1994

Postantibiotic effect of roxithromycin on streptolysin O production, hydrophobicity, and bactericidal activity of PMNL by Streptococcus pyogenes.

Exposure of Streptococcus pyogenes to 5 x minimum inhibitory concentration of roxithromycin for 1 h produced a significant postantibiotic effect. More than 2.5 h was necessary for roxithromycin-treated bacteria to increase by 1 log10 in colony-forming units after drug removal, compared with the unexposed cells. After exposure to and removal of the drug, treated cells failed to exhibit normal hemolytic activity for at least 4 h. The inhibitory effect persisted for 20 h after drug removal, although the extent of growth for treated and untreated cells was almost the same. Hydrophobicity of treated cells, studied throughout the logarithmic growth phase with a water-hexadecan two-phase system, was markedly decreased by 40%, compared with untreated cells 4 h after drug removal. Cells that had been treated with roxithromycin became more susceptible to the bactericidal activity of human PMNL than untreated bacteria. The data indicate that some of the metabolic activity that contributes to the virulence of S. pyogenes is affected by postexposure to roxithromycin, and its minimum inhibitory concentration and serum level might not be the best indicators of efficacy in this class of drugs.

Bacterial Proteins↗
PubMed1962

Cell wall replication in Streptococcus pyogenes.

Group A streptococci (Streptococcus pyogenes) of several different serological types were grown in fluorescein-labeled homologous type or group-specific globulins, thereby labeling the antigen-containing cell walls. Specific precipitation or inhibition of the labeled antibody, followed by continued incubation and examination at intervals by ultraviolet, phase, and dark-field microscopy, showed that new cell wall was then nonfluorescent. These nonfluorescent portions were differentiated by a reverse technique of culture in unlabeled globulin, followed by antibody precipitation, further growth, and fluorescent-antibody staining. This technique of differential labeling of cell wall has permitted following, for the first time in a living system, the fate of cell wall formed at different times. The results suggest that cell wall synthesis in actively growing cultures usually occurs simultaneously at at least two sites per coccus, each site representing stages in successive divisions, and that cell wall growth in Streptococcus pyogenes is not by diffuse intercalation with old wall, but is initiated at and extends both peripherally and centripetally from the coccal equator.

Cell Division↗
PubMed1997

Superantigenicity of helper T-cell mitogen (SPM-2) isolated from culture supernatants of Streptococcus pyogenes.

A superantigen (Streptococcus pyogenes mitogen-2; SPM-2) that stimulates human helper T cells bearing unique types of variable domains of T-cell receptor beta-chain (TCR V beta) was isolated from the culture supernatant of S. pyogenes strain T12. The active molecule isolated by diethylaminoethyl (DEAE)-cellulose chromatography and isoelectric focusing was a protein with a molecular weight (MW) of 29,000 and isoelectric point (pl) of 6.0. This new superantigen was found to activate preferentially V beta 4+, 7+, and 8+ T cells, whereas recombinant streptococcal pyrogenic exotoxin A and C activated V beta 12+ and V beta 2+ T cells, respectively, as determined by flow cytometry and reverse transcriptase-polymerase chain reaction (RT-PCR) methods. This proliferative response was significantly inhibited by anti-HLA-DR monoclonal antibody, and required paraformaldehyde-fixed antigen-presenting cells (APC), indicating that this action is dependent on major histocompatibility complex (MHC) class II molecules without processing. Analysis of the amino-terminal amino acid sequence of the molecule failed to find any identical or significantly homologous proteins. We have previously reported that cytoplasmic membrane-associated protein (CAP), a streptococcal superantigen isolated from the cell membranes of S. pyogenes T12 strain, stimulated mainly V beta 8+ T cells. Both SPM-2 and CAP preferentially stimulated helper T cells, and rabbit antiserum against SPM-2 completely neutralized the T-cell-stimulating activities of CAP, suggesting that SPM-2 and CAP belong to a family of streptococcal mitogenic proteins. The SPM-2 activity with stimulation of V beta 8+ T cells was detected extensively in the culture fluids of group A streptococci, but not in those of other streptococcal species, including groups B and D streptococci, and most of the activities detected were completely inhibited by anti-SPM-2 serum. These results indicate that SPM-2 may be a newly discovered superantigen molecule, which can be commonly synthesized by group A streptococci.

Amino Acid Sequence↗
PubMed1975

Transduction of drug resistance to tetracycline, chloramphenicol, macrolides, lincomycin and clindamycin with phages induced from Streptococcus pyogenes.

Strains of Streptococcus pyogenes isolated from pediatric patients with acute infections which were resistant to one or more of the antibiotics, tetracycline (TC), chloramphenicol (CP), macrolide antibiotics (erythromycin, kitasamycin, oleandomycin, josamycin), lincomycin (LCM) and clindamycin (CLM), were used for transduction of drug resistance. These drug-resistant strains were treated with mitomycin C to induce phages and transduction of drug resistance was attempted by means of phages so induced. It was found that transduction of resistance to the above antibiotics was possible. The transductants obtained on TC-containing selective agar plate were resistant to TC alone while those produced on CP- or erythromycin (EM)-containing selective agar plate were resistant to CP, macrolide antibiotics (Mac), LCM and CLM. From this finding, it was inferred that transduction of resistance to TC, CP, Mac, LCM and CLM via phages occurred in two different patterns, i.e., transfer of resistance to TC alone and that of resistance to CP, Mac, LCM and CLM. All of the transductants obtained were found to belong to group A. In T-typing, they were of the same T-12 type as the donor and recipient strains in a majority of cases though some were not typable.

Anti-Bacterial Agents↗
PubMed2002

Existence of two emm-like "mrp" and "emm" genes in the mga regulon of the Streptococcus pyogenes strain ST4547.

Streptococcus pyogenes ST4547 is an opacity factor negative strain, which has been recently reported as a new emm type from Malaysia. Nucleotide sequencing of the mga regulon of this strain showed the existence of two emm-like genes. The emm gene located upstream of the scpA gene comprises 1305 nucleotides encoding the putative precursor M protein of 435 amino acids in length with an M(r) of 49 kDa. or a predicted mature protein of 394 amino acids with an M(r) of 44.8 kDa. Another gene mrpST4547 was located upstream of the emm gene and downstream of the mga gene. The sequence of this mrp gene comprises 1167 nucleotides encoding a predicted protein of 388 amino acids in length with an M(r) of 42.2 kDa. or a predicted mature protein of 347 amino acids with an M(r) of 37.9 kDa. The mga regulon of strain ST4547 has a mosaic structure comprising segments, which originated from different OF positive and OF negative strains. The sequences flanking the hyper-variable and C repeats of the emmST4547 gene showed high similarity to corresponding regions in the mga regulon of OF positive strains notably M15, M4, M22 and M50. In contrast, the sequence within the hyper-variable and C repeat regions of the emmST4547 gene revealed high similarity to equivalent regions in the OF negative strains. These data indicates that horizontal transfer of emm-like gene could have occurred between OF positive and OF negative strains resulting in architectural divergence in the mga regulon.

Amino Acid Sequence↗
PubMed2001

[Severe Streptococcus pyogenes cutaneous infections].

Streptococcus pyogenes is the first bacteria encountered in severe cutaneous infections in children. They enclose erysipela (papillar derma concerned more than hypoderma, lymphatic involvement) and necrotising fasciitis NF (focus on fascia and muscles with extension to hypoderma and reticular derma; venous thrombosis; hypodermic and aponevrotic necrosis). A skin lesion is the entrance of infection: varicella lesions are a major factor of NF. In France, sporadic cases in children are observed. The annual incidence of S. pyogenes invasive diseases is 1/100,000 children under 5 years of age and 0.6/100,000 children under 15 years of age. In North America, resurgence has been notified during the past ten years with mortality and morbidity due to NF and toxic shock syndromes. Interaction between bacteria and host, natural reservoir, explains the physiopathology. During the past ten years, some serotypes have become more invasive and virulent. Any cutaneous lesion interrupt the dermal barrier. Bacterial wall, proteins M and adhesins permit colonisation. Four pyrogenic exotoxins are superantigens; some facilitate inflammation, tissular lesions and shock; other participate to bacterial extension. In young children, immune response is immature. Albeit causal link between non-steroids anti-inflammatory drugs and NF in varicella children was not clearly demonstrated, caution should be kept in mind. Diagnosis of erysipela is clinical: sudden appearance of an inflammatory zone, most often on legs, with high fever and pain; sometime peripheral surelevation, lymphangitis, adenopathia. Other aspects open discussion with NF. In NF are in favour, added to high fever, huge pain, erythema and oedema: rapid extension of lesions, cutaneous hypoesthesia appearance, gap between intense severe general status (toxic shock syndrome) and paucity of local signs. NF is a medico-surgical emergency. Early surgery with complete excision of necrotic tissues permit survival. Magnetic resonance is useful in subacute NF. Microbiological diagnosis is possible in 20 to 80% of cases, using combined methods. Blood cultures identify the bacteria in 5 to 20%, skin lesion samples in 30%. Local samples are less useful even with modern techniques. Therapeutic strategy depends on initial diagnosis. Intra-venous antibiotics are necessary: penicillin (G, A or M) is first line therapy. In erysipela, ten days allow a rapid cure without sequellae. In NF, antibiotics are associated with intensive care and surgery. A late diagnosis, a too late surgery explain 16 to 36% of deaths encountered.

Adolescent↗
PubMed1988

Vaginitis caused by nutritionally variant Streptococcus pyogenes.

A nutritionally variant Streptococcus pyogenes was isolated from a vaginal specimen. The organism was isolated in essentially pure culture with a few colonies of normal vaginal flora. The bacterium was identified as Streptococcus pyogenes with the use of rapid test kits and the presence of group A antigen.

Female↗
PubMedDate not supplied

[Invasive infections by Streptococcus pyogenes].

Invasive infections by Streptococcus pyogenes continually increase both in France and in others industrialized countries. Because of the seriousness, the rapidity of the evolution and the epidemic potentialities, guidelines for managing these infections are requested by the Superior Council of Public Hygiene of France. The authors report herein a case of an adult stricken down by a violent evolution due to Streptococcus pyogenes. They point up how diagnosis, treatment and prophylaxis for family circle are difficult.

Diagnosis, Differential↗
PubMed2006

[First reported cases of Streptococcus pyogenes meningitis in Central African Republic].

Streptococcus pyogenes or group A streptococcus is an uncommon cause of bacterial meningitis. The purpose of this report is to describe two cases of Streptococcus pyogenes meningitis observed in Bangui, Central African Republic. The first case occurred in a 44-year-old woman who also presented pyodermitis. The second case involved a 34-year-old woman who also presented chronic middle ear infection and AIDS. Both strains of Streptococcus pyogenes were classified as biotype group 5 and showed resistance to tetracycline. They were also T-nontypable and of the emm 117 genotype and 117.1 subtype. Pulsed-field gel electrophoresis confirmed that both strains originated from the same clone.

Acquired Immunodeficiency Syndrome↗
PubMed2002

Immunological response mounted by Aboriginal Australians living in the Northern Territory of Australia against Streptococcus pyogenes serum opacity factor.

Streptococcus pyogenes (Group A streptococcus) interacts with host fibronectin via a number of distinct surface components. The streptococcal serum opacity factor (SOF) is a cell-surface protein of S. pyogenes which causes opalescence of human serum and mediates bacterial binding to fibronectin. In this study, hexahistidyl-tagged fusion proteins encompassing full-length SOF, and domains of SOF encompassing opacity factor activity and fibronectin-binding regions, were used in the characterization of the Aboriginal immune response to SOF. Anti-SOF serum IgG responses were found to be significantly higher (P<0.0001) in Aboriginal adults and children when compared to a non-Aboriginal adult group. The Aboriginal immune response against the fibronectin-binding region of SOF was significantly reduced when compared to the response against the whole SOF protein and N-terminal domains examined in this study (P<0.001). This pattern of immune response was also observed in rabbits immunized with recombinant SOF. Comparison of the deduced amino acid sequence of SOF from a number of common Australian isolates with other SOF sequences revealed that the N-terminus of SOF exhibits sequence similarity values ranging from 42.9% to 96.5%. The C-terminus containing the fibronectin-binding domain and membrane-spanning regions was more highly conserved, exhibiting sequence similarity values ranging from 84.6% to 100% within the fibronectin-binding repeats. These data suggest that the immune response against SOF is directed toward the variable N-terminus of the SOF protein. Phylogenetic analysis indicated that the sof genes of S. pyogenes do not exhibit geographical variation.

Adhesins, Bacterial↗
PubMed2002

Increased prevalence of erythromycin resistance in streptococci: substantial upsurge in erythromycin-resistant M phenotype in Streptococcus pyogenes (1979-1998) but not in Streptococcus pneumoniae (1985-1999) in Taiwan.

A total of 394 nonduplicate isolates of Streptococcus pyogenes collected from 1979 to 1998 and 267 nonduplicate isolates of Streptococcus pneumoniae collected from October, 1998, to May, 1999, in Taiwan were evaluated. Among the 220 erythromycin-resistant (MIC, > or =1 microg/ml) S. pyogenes isolates, 35% had an M phenotype and 65% had an ML phenotype (inducible resistance [iML], 0.5%, and constitutive resistance [cML], 64.5%). Among the 243 erythromycin-resistant S. pneumoniae isolates, the majority (65.4%) had an ML phenotype (iML, 0.4%, and cML, 65%) and 34.6% had an M phenotype. A substantial upsurge in the incidence of M-phenotype erythromycin-resistant isolates was found with time for S. pyogenes (0% in 1979-1984 and 100% in 1997-1998), and an increasing incidence of M-phenotype among erythromycin-resistant S. pneumoniae was also noted (<20% before 1994 and 45.4% in 1999). All S. pyogenes and all but four S. pneumoniae isolates exhibiting a cML or iML phenotype had harbored the ermAM gene. The presence of the mefA gene was demonstrated in all isolates of S. pyogenes and the mefE gene in all but four S. pneumoniae isolates exhibiting the M phenotype. Due to the increasing susceptibility of S. pyogenes and S. pneumoniae isolates to clindamycin, susceptibility tests of these two organisms to macrolides and clindamycin should be performed simultaneously in the clinical microbiology laboratory, particularly in areas with high rates of macrolide resistance.

Anti-Bacterial Agents↗
PubMed2002

Investigation of risk factors for tonsillopharyngitis with macrolide resistant Streptococcus pyogenes in Turkish children.

BACKGROUND: Streptococcus pyogenes is the most important causative agent of tonsillopharyngitis. Although penicillin is the drug of choice in streptococcal tonsillopharyngitis, macrolides are recommended drugs in patients who have an allergy to penicillin. However, resistance to macrolides is an important problem in some regions of the world. Risk factors for resistance development have not been investigated sufficiently. OBJECTIVES: To investigate the risk factors for the development of tonsillopharyngitis with macrolide resistant S. pyogenes. METHODS: Three hundred and forty-five children with tonsillopharyngitis caused by S. pyogenes were investigated for various risk factors. Streptococcus pyogenes isolated from children's throat culture were examined for erythromycin, clarithromycin and azithromycin susceptibility. RESULTS: Two hundred and sixty-three children were found eligible for the analysis of risk factors. Resistances to erythromycin, clarithromycin and azithromycin were detected as 3.8, 4.2 and 4.2%, respectively. Macrolide use of the family members in the last 3 months (odds ratio = 7.04, P = 0.005) has been determined to be a risk factor for the development of tonsillopharyngitis with macrolide resistant S. pyogenes. CONCLUSION: Restriction of macrolide antibiotic use appears to be the most important measure to prevent the development of tonsillopharyngitis with resistant S. pyogenes.

Adolescent↗
PubMed1996

Inducer expulsion and the occurrence of an HPr(Ser-P)-activated sugar-phosphate phosphatase in Enterococcus faecalis and Streptococcus pyogenes.

Inducer expulsion, a phenomenon in which rapidly metabolizable sugars cause cytoplasmic dephosphorylation and efflux of pre-accumulated sugar-phosphates (sugar-P), has been documented for Streptococcus pyogenes, Streptococcus bovis, and Lactococcus lactis, but not for other Gram-positive bacteria. Using intact cells and membrane vesicles, we show that Enterococcus faecalis exhibits both inducer exclusion and inducer expulsion, and that the latter phenomenon is dependent on the metabolite-activated ATP-dependent HPr(Ser) kinase that phosphorylates Ser-46 in HPr of the phosphotransferase system. A small, heat-stable, membrane-associated, HPr(Ser-P)-activated sugar-P phosphatase (Pase II), previously identified only in Lc. lactis, is shown to be present in extracts of Enterococcus faecalis and Streptococcus pyogenes but not in those of Staphylococcus aureus, Streptococcus mutans, Streptococcus salivarius, or Bacillis subtilis, organisms that do not exhibit the inducer expulsion phenomenon. Further, Lactobacillus brevis, an organism that exhibits inducer expulsion by a different mechanism, also apparently lacks Pase II. The results reveal that Pase II is present in those organisms that exhibit the coupled sugar-P hydrolysis/expulsion mechanism but not those that lack this mechanism. They provide correlative evidence that Pase II initiates inducer expulsion in species of enterococci, streptococci and lactococci.

Biological Transport↗
PubMed2005

Acute otitis media caused by Streptococcus pyogenes in children.

BACKGROUND: Streptococcus pyogenes, or group A beta -hemolytic Streptococcus (GAS), is an important causative agent of bacterial pharyngotonsillititis and skin, soft-tissue, and invasive infections. Although it is also an important pathogen in acute otitis media (AOM), its exact role has not been determined. METHODS: Patients aged 0-18 years with AOM, from whom a specimen of middle-ear fluid was obtained and cultured during 1999-2003, were enrolled. Streptococcus pneumoniae, Haemophilus influenzae, Moraxella catarrhalis, and GAS were considered pathogens. Information collected included demographic characteristics, clinical history, and signs and symptoms. RESULTS: GAS otitis was observed in 350 (3.1%) of 11,311 episodes (of which 117 were also culture-positive for other pathogens). The other 10,961 episodes involved H. influenzae only (n = 2507), S. pneumoniae only (n = 2131), dual infection with H. influenzae and S. pneumoniae (n = 1290), M. catarrhalis only (n = 129), and other combinations of pathogens (n = 271). Increased age and Jewish ethnicity were independent, significant, positive risk factors for GAS AOM, and fall season was a negative risk factor. Episodes of GAS infection were less frequently bilateral, febrile, and accompanied by other systemic findings than were other episodes of other types of infection. Most patients with GAS AOM presented with acute drainage from the ears. A lower proportion of cases of AOM were due to GAS in children with recurrent AOM and in patients recently treated with antibiotics, compared with patients with AOM who did not have these factors. The risk for mastoiditis was highest among patients with GAS AOM, compared with patients infected with other pathogens: 11.6 episodes per 1000 episodes of GAS AOM, compared with 2.2, 0.3, and 0 episodes of mastoiditis per 1000 episodes of AOM due to S. pneumoniae, H. influenzae, and M. catarrhalis, respectively. CONCLUSION: Compared with AOM caused by pathogens other than GAS, GAS AOM is characterized by older age and higher local aggressiveness manifested by lower rates of fever and respiratory symptoms and higher rates of tympanic perforation and mastoiditis.

Acute Disease↗