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Beres SB, Olsen RJ, Long SW, Eraso JM, Boukthir S, Faili A, Kayal S, Musser JM. Analysis of the Genomics and Mouse Virulence of an Emergent Clone of Streptococcus dysgalactiae Subspecies equisimilis. Microbiol Spectr 2023; 11:e0455022. [PMID: 36971562 PMCID: PMC10100674 DOI: 10.1128/spectrum.04550-22] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/08/2022] [Accepted: 03/04/2023] [Indexed: 03/29/2023] Open
Abstract
Streptococcus dysgalactiae subsp. equisimilis is a bacterial pathogen that is increasingly recognized as a cause of severe human infections. Much less is known about the genomics and infection pathogenesis of S. dysgalactiae subsp. equisimilis strains compared to the closely related bacterium Streptococcus pyogenes. To address these knowledge deficits, we sequenced to closure the genomes of seven S. dysgalactiae subsp. equisimilis human isolates, including six that were emm type stG62647. Recently, for unknown reasons, strains of this emm type have emerged and caused an increasing number of severe human infections in several countries. The genomes of these seven strains vary between 2.15 and 2.21 Mbp. The core chromosomes of these six S. dysgalactiae subsp. equisimilis stG62647 strains are closely related, differing on average by only 495 single-nucleotide polymorphisms, consistent with a recent descent from a common progenitor. The largest source of genetic diversity among these seven isolates is differences in putative mobile genetic elements, both chromosomal and extrachromosomal. Consistent with the epidemiological observations of increased frequency and severity of infections, both stG62647 strains studied were significantly more virulent than a strain of emm type stC74a in a mouse model of necrotizing myositis, as assessed by bacterial CFU burden, lesion size, and survival curves. Taken together, our genomic and pathogenesis data show the strains of emm type stG62647 we studied are closely genetically related and have enhanced virulence in a mouse model of severe invasive disease. Our findings underscore the need for expanded study of the genomics and molecular pathogenesis of S. dysgalactiae subsp. equisimilis strains causing human infections. IMPORTANCE Our studies addressed a critical knowledge gap in understanding the genomics and virulence of the bacterial pathogen Streptococcus dysgalactiae subsp. equisimilis. S. dysgalactiae subsp. equisimilis strains are responsible for a recent increase in severe human infections in some countries. We determined that certain S. dysgalactiae subsp. equisimilis strains are genetically descended from a common ancestor and that these strains can cause severe infections in a mouse model of necrotizing myositis. Our findings highlight the need for expanded studies on the genomics and pathogenic mechanisms of this understudied subspecies of the Streptococcus family.
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Affiliation(s)
- Stephen B. Beres
- Laboratory of Molecular and Translational Human Infectious Disease Research, Center for Infectious Diseases, Department of Pathology and Genomic Medicine, Houston Methodist Research Institute and Houston Methodist Hospital, Houston, Texas, USA
| | - Randall J. Olsen
- Laboratory of Molecular and Translational Human Infectious Disease Research, Center for Infectious Diseases, Department of Pathology and Genomic Medicine, Houston Methodist Research Institute and Houston Methodist Hospital, Houston, Texas, USA
- Department of Pathology and Laboratory Medicine, Weill Cornell Medical College, New York, New York, USA
- Department of Microbiology and Immunology, Weill Cornell Medical College, New York, New York, USA
| | - S. Wesley Long
- Laboratory of Molecular and Translational Human Infectious Disease Research, Center for Infectious Diseases, Department of Pathology and Genomic Medicine, Houston Methodist Research Institute and Houston Methodist Hospital, Houston, Texas, USA
- Department of Pathology and Laboratory Medicine, Weill Cornell Medical College, New York, New York, USA
- Department of Microbiology and Immunology, Weill Cornell Medical College, New York, New York, USA
| | - Jesus M. Eraso
- Laboratory of Molecular and Translational Human Infectious Disease Research, Center for Infectious Diseases, Department of Pathology and Genomic Medicine, Houston Methodist Research Institute and Houston Methodist Hospital, Houston, Texas, USA
- Department of Pathology and Laboratory Medicine, Weill Cornell Medical College, New York, New York, USA
| | - Sarrah Boukthir
- CHU de Rennes, Service de Bacteriologie-Hygiène Hospitalière, Rennes, France
- INSERM, CIC 1414, Rennes, France
- Université Rennes 1, Faculté de Médecine, Rennes, France
| | - Ahmad Faili
- INSERM, CIC 1414, Rennes, France
- Université Rennes 1, Faculté de Pharmacie, Rennes, France
- Chemistry, Oncogenesis, Stress, and Signaling, INSERM 1242, Rennes, France
| | - Samer Kayal
- CHU de Rennes, Service de Bacteriologie-Hygiène Hospitalière, Rennes, France
- INSERM, CIC 1414, Rennes, France
- Université Rennes 1, Faculté de Médecine, Rennes, France
- Chemistry, Oncogenesis, Stress, and Signaling, INSERM 1242, Rennes, France
| | - James M. Musser
- Laboratory of Molecular and Translational Human Infectious Disease Research, Center for Infectious Diseases, Department of Pathology and Genomic Medicine, Houston Methodist Research Institute and Houston Methodist Hospital, Houston, Texas, USA
- Department of Pathology and Laboratory Medicine, Weill Cornell Medical College, New York, New York, USA
- Department of Microbiology and Immunology, Weill Cornell Medical College, New York, New York, USA
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Bläckberg A, de Neergaard T, Frick IM, Nordenfelt P, Lood R, Rasmussen M. Lack of Opsonic Antibody Responses to Invasive Infections With Streptococcus dysgalactiae. Front Microbiol 2021; 12:635591. [PMID: 33986732 PMCID: PMC8111088 DOI: 10.3389/fmicb.2021.635591] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/01/2020] [Accepted: 03/31/2021] [Indexed: 11/29/2022] Open
Abstract
Introduction Streptococcus dysgalactiae can cause severe recurrent infections. This study aimed to investigate antibody responses following S. dysgalactiae bacteraemia and possible development of protective immunity. Materials and Methods Patients with S. dysgalactiae bacteraemia in the county of Skåne between 2017 and 2018 were prospectively included. Acute and convalescent sera were obtained. All isolates were emm typed and enzyme-linked immunosorbent assay (ELISA) was utilised to analyse specific antibody responses to bacteria and antigens. Bactericidal- and phagocytosis assays were applied to further establish antibody function. Results Sixteen patients with S. dysgalactiae bacteraemia were included of whom one had recurrent episodes of bacteraemia. Using ELISA with S. dysgalactiae isolates and mutants, development of IgG antibodies was demonstrated in few patients. Type-specific antibodies were demonstrated in one patient when recombinant M proteins as antigens, were applied. The type-specific serum mediated a small increase in phagocytosis but did not facilitate increased killing of the S. dysgalactiae isolate, carrying that M protein, in blood or by phagocytic cells. Conclusion S. dysgalactiae bacteraemia sometimes results in increased levels of antibodies to the infecting pathogen. We did not find evidence that these antibodies are effectively opsonising. Apparent failure to produce opsonising antibodies might partially explain why S. dysgalactiae can cause recurrent invasive infections in the same host.
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Affiliation(s)
- Anna Bläckberg
- Division of Infection Medicine, Department of Clinical Sciences Lund, Lund University, Lund, Sweden.,Skåne University Hospital, Department of Infectious Diseases, Lund, Sweden
| | - Therese de Neergaard
- Division of Infection Medicine, Department of Clinical Sciences Lund, Lund University, Lund, Sweden
| | - Inga-Maria Frick
- Division of Infection Medicine, Department of Clinical Sciences Lund, Lund University, Lund, Sweden
| | - Pontus Nordenfelt
- Division of Infection Medicine, Department of Clinical Sciences Lund, Lund University, Lund, Sweden
| | - Rolf Lood
- Division of Infection Medicine, Department of Clinical Sciences Lund, Lund University, Lund, Sweden
| | - Magnus Rasmussen
- Division of Infection Medicine, Department of Clinical Sciences Lund, Lund University, Lund, Sweden.,Skåne University Hospital, Department of Infectious Diseases, Lund, Sweden
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Infections Caused by Group C and G Streptococcus ( Streptococcus dysgalactiae subsp. equisimilis and Others): Epidemiological and Clinical Aspects. Microbiol Spectr 2019; 7. [PMID: 30977463 DOI: 10.1128/microbiolspec.gpp3-0016-2018] [Citation(s) in RCA: 31] [Impact Index Per Article: 6.2] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/27/2023] Open
Abstract
Streptococci carrying serogroup C and G antigens, and in particular, Streptococcus dysgalactiae subsp. equisimilis (SDSE), are emerging human pathogens that are increasingly isolated from patients with a myriad of infections that range from mundane to life-threatening. SDSE is microbiologically similar to Streptococcus pyogenes. These streptococci frequently cause infections of the throat and skin and soft tissues. Moreover, they may invade the bloodstream and disseminate widely to many deep tissue sites, including the endocardium. Life-threatening invasive infections due to SDSE, including the streptococcal toxic shock syndrome, occur most frequently in patients with severe underlying medical diseases. Treatment with penicillin is adequate under most circumstances, but treatment failure occurs. SDSE may also be resistant to other antibiotic classes including tetracyclines, macrolides, and clindamycin. Most human infections caused by groups C and G streptococci are transmitted from person to person, but infections due to Streptococcus equi subsp. zooepidemicus (and, rarely, to S. equi subsp. equi) are zoonoses. Transmission of these latter species occurs by animal contact or by contamination of food products and has been associated with the development of poststreptococcal glomerulonephritis. Members of the Streptococcus anginosus group, usually classified with the viridans group of streptococci, are associated with a variety of pyogenic infections.
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Christensen JM, Brat GA, Johnson KE, Chen Y, Buretta KJ, Cooney DS, Brandacher G, Lee WPA, Li X, Sacks JM. Monocytes loaded with indocyanine green as active homing contrast agents permit optical differentiation of infectious and non-infectious inflammation. PLoS One 2013; 8:e81430. [PMID: 24282595 PMCID: PMC3839882 DOI: 10.1371/journal.pone.0081430] [Citation(s) in RCA: 3] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/04/2013] [Accepted: 10/13/2013] [Indexed: 01/10/2023] Open
Abstract
Distinguishing cutaneous infection from sterile inflammation is a diagnostic challenge and currently relies upon subjective interpretation of clinical parameters, microbiological data, and nonspecific imaging. Assessing characteristic variations in leukocytic infiltration may provide more specific information. In this study, we demonstrate that homing of systemically administered monocytes tagged using indocyanine green (ICG), an FDA-approved near infrared dye, may be assessed non-invasively using clinically-applicable laser angiography systems to investigate cutaneous inflammatory processes. RAW 264.7 mouse monocytes co-incubated with ICG fluoresce brightly in the near infrared range. In vitro, the loaded cells retained the ability to chemotax toward monocyte chemotactic protein-1. Following intravascular injection of loaded cells into BALB/c mice with induced sterile inflammation (Complete Freund’s Adjuvant inoculation) or infection (Group A Streptococcus inoculation) of the hind limb, non-invasive whole animal imaging revealed local fluorescence at the inoculation site. There was significantly higher fluorescence of the inoculation site in the infection model than in the inflammation model as early as 2 hours after injection (p<0.05). Microscopic examination of bacterial inoculation site tissue revealed points of near infrared fluorescence, suggesting the presence of ICG-loaded cells. Development of a non-invasive technique to rapidly image inflammatory states without radiation may lead to new tools to distinguish infectious conditions from sterile inflammatory conditions at the bedside.
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Affiliation(s)
- Joani M. Christensen
- Department of Plastic and Reconstructive Surgery, Johns Hopkins University School of Medicine, Baltimore, Maryland, United States of America
| | - Gabriel A. Brat
- Department of Plastic and Reconstructive Surgery, Johns Hopkins University School of Medicine, Baltimore, Maryland, United States of America
| | - Kristine E. Johnson
- Division of Infectious Diseases, Department of Medicine, Johns Hopkins Bayview Medical Center, Baltimore, Maryland, United States of America
| | - Yongping Chen
- Department of Biomedical Engineering, Johns Hopkins University School of Medicine, Baltimore, Maryland, United States of America
| | - Kate J. Buretta
- Department of Plastic and Reconstructive Surgery, Johns Hopkins University School of Medicine, Baltimore, Maryland, United States of America
| | - Damon S. Cooney
- Department of Plastic and Reconstructive Surgery, Johns Hopkins University School of Medicine, Baltimore, Maryland, United States of America
| | - Gerald Brandacher
- Department of Plastic and Reconstructive Surgery, Johns Hopkins University School of Medicine, Baltimore, Maryland, United States of America
| | - W. P. Andrew Lee
- Department of Plastic and Reconstructive Surgery, Johns Hopkins University School of Medicine, Baltimore, Maryland, United States of America
| | - Xingde Li
- Department of Biomedical Engineering, Johns Hopkins University School of Medicine, Baltimore, Maryland, United States of America
| | - Justin M. Sacks
- Department of Plastic and Reconstructive Surgery, Johns Hopkins University School of Medicine, Baltimore, Maryland, United States of America
- * E-mail:
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Vaccination Against Rheumatic Heart Disease: A Review of Current Research Strategies and Challenges. Curr Infect Dis Rep 2012; 14:381-90. [DOI: 10.1007/s11908-012-0263-7] [Citation(s) in RCA: 12] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/30/2023]
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Molecular mechanisms of Streptococcus dysgalactiae subsp equisimilis enabling intravascular persistence. Microbes Infect 2012; 14:329-34. [DOI: 10.1016/j.micinf.2011.10.008] [Citation(s) in RCA: 7] [Impact Index Per Article: 0.6] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/28/2011] [Revised: 10/24/2011] [Accepted: 10/24/2011] [Indexed: 10/15/2022]
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Steer AC, Jenney AWJ, Kado J, Batzloff MR, La Vincente S, Waqatakirewa L, Mulholland EK, Carapetis JR. High burden of impetigo and scabies in a tropical country. PLoS Negl Trop Dis 2009; 3:e467. [PMID: 19547749 PMCID: PMC2694270 DOI: 10.1371/journal.pntd.0000467] [Citation(s) in RCA: 95] [Impact Index Per Article: 6.3] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/05/2009] [Accepted: 05/26/2009] [Indexed: 11/20/2022] Open
Abstract
Background Impetigo and scabies are endemic diseases in many tropical countries; however the epidemiology of these diseases is poorly understood in many areas, particularly in the Pacific. Methodology/Principal Findings We conducted three epidemiological studies in 2006 and 2007 to determine the burden of disease due to impetigo and scabies in children in Fiji using simple and easily reproducible methodology. Two studies were performed in primary school children (one study was a cross-sectional study and the other a prospective cohort study over ten months) and one study was performed in infants (cross-sectional). The prevalence of active impetigo was 25.6% (95% CI 24.1–27.1) in primary school children and 12.2% (95% CI 9.3–15.6) in infants. The prevalence of scabies was 18.5% (95% CI 17.2–19.8) in primary school children and 14.0% (95% CI 10.8–17.2) in infants. The incidence density of active impetigo, group A streptococcal (GAS) impetigo, Staphylococcus aureus impetigo and scabies was 122, 80, 64 and 51 cases per 100 child-years respectively. Impetigo was strongly associated with scabies infestation (odds ratio, OR, 2.4, 95% CI 1.6–3.7) and was more common in Indigenous Fijian children when compared with children of other ethnicities (OR 3.6, 95% CI 2.7–4.7). The majority of cases of active impetigo in the children in our study were caused by GAS. S. aureus was also a common cause (57.4% in school aged children and 69% in infants). Conclusions/Significance These data suggest that the impetigo and scabies disease burden in children in Fiji has been underestimated, and possibly other tropical developing countries in the Pacific. These diseases are more than benign nuisance diseases and consideration needs to be given to expanded public health initiatives to improve their control. Scabies and impetigo are often thought of as nuisance diseases, but have the potential to cause a great deal of morbidity and even mortality if infection becomes complicated. Accurate assessments of these diseases are lacking, particularly in tropical developing countries. We performed a series of studies in infants and primary school children in Fiji, a tropical developing country in the South Pacific. Impetigo was very common: more than a quarter of school-aged children and 12% of infants had active impetigo. Scabies was also very common affecting 18% of school children and 14% of infants. The group A streptococcus was the most common infective organism followed by Staphylococcus aureus. The size of the problem has been underestimated, particularly in the Pacific. It is time for more concerted public health efforts in controlling impetigo and scabies.
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Affiliation(s)
- Andrew C Steer
- Centre for International Child Health, University of Melbourne, Melbourne, Australia.
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McDonald M, Towers RJ, Andrews RM, Carapetis JR, Currie BJ. Epidemiology of Streptococcus dysgalactiae subsp. equisimilis in tropical communities, Northern Australia. Emerg Infect Dis 2007; 13:1694-700. [PMID: 18217553 PMCID: PMC3375807 DOI: 10.3201/eid1311.061258] [Citation(s) in RCA: 39] [Impact Index Per Article: 2.3] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/19/2022] Open
Abstract
Streptococcus dysgalactiae subsp. equisimilis (groups C and G streptococci [GCS/GGS]) is an increasingly recognized human pathogen, although it may follow indirect pathways. Prospective surveillance of selected households in 3 remote Aboriginal communities in Australia provided 337 GCS/GGS isolates that were emm sequence-typed. Lancefield group C isolates (GCS) were localized to specific households and group G isolates (GGS) were more evenly distributed. GCS/GGS was more frequently recovered from the throat than group A streptococci (GAS [S. pyogenes]) but rarely recovered from skin sores, and then only with Staphylococcus aureus or GAS. Symptomatic GGS/GGC pharyngitis was also rare. Specific emm sequence types of GCS/GGS did not appear to cycle through the communities (sequential strain replacement) in a manner suggesting acquisition of type-specific immunity. These communities already have high levels of streptococcal and poststreptococcal disease. GCS/GGS may increase in importance as it acquires key virulence factors from GAS by lateral gene transfer.
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Affiliation(s)
- Malcolm McDonald
- Menzies School of Health Research, Charles Darwin University, Casuarina, Northern Territory, Australia.
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Kaplan EL, Bisno AL. Antecedent Streptococcal Infection in Acute Rheumatic Fever. Clin Infect Dis 2006; 43:690-2. [PMID: 16912940 DOI: 10.1086/506944] [Citation(s) in RCA: 21] [Impact Index Per Article: 1.2] [Reference Citation Analysis] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/23/2006] [Accepted: 05/27/2006] [Indexed: 11/03/2022] Open
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Cohen-Poradosu R, Jaffe J, Lavi D, Grisariu-Greenzaid S, Nir-Paz R, Valinsky L, Dan-Goor M, Block C, Beall B, Moses AE. Group G streptococcal bacteremia in Jerusalem. Emerg Infect Dis 2004; 10:1455-60. [PMID: 15496248 PMCID: PMC3320404 DOI: 10.3201/eid1008.030840] [Citation(s) in RCA: 84] [Impact Index Per Article: 4.2] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/22/2022] Open
Abstract
Recurrent group G Steptococcus bacteremia, associated with lymphatic disorders and possibly emmstG840.0, is described. Group G Streptococcus (GGS) can cause severe infections, including bacteremia. These organisms often express a surface protein homologous to the Streptococcus pyogenes M protein. We retrospectively studied the characteristics of patients from the Hadassah Medical Center with GGS bacteremia from 1989 to 2000. Ninety-four cases of GGS bacteremia were identified in 84 patients. The median age was 62 years, 54% were males, and 92% had underlying diseases (35% had a malignancy, and 35% had diabetes mellitus). The most frequent source for bacteremia was cellulitis (61%). emm typing of 56 available isolates disclosed 13 different types, including 2 novel types. Six patients had recurrent bacteremia with two to four bacteremic episodes, five had chronic lymphatic disorders, and two had emm type stG840.0 in every episode. Recurrent bacteremia has not been described for invasive group A Streptococcus. We describe an entity of recurrent GGS bacteremia, which is associated with lymphatic disorders and possibly with emm stG840.0.
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Affiliation(s)
| | - Joseph Jaffe
- Hadassah-Hebrew University Medical Center, Jerusalem, Israel
| | - David Lavi
- Hadassah-Hebrew University Medical Center, Jerusalem, Israel
| | | | - Ran Nir-Paz
- Hadassah-Hebrew University Medical Center, Jerusalem, Israel
| | - Lea Valinsky
- Ministry of Health Central Laboratory, Jerusalem, Israel
| | - Mary Dan-Goor
- Hebrew University-Hadassah Medical School, Jerusalem, Israel
| | - Colin Block
- Hadassah-Hebrew University Medical Center, Jerusalem, Israel
| | - Bernard Beall
- Centers for Disease Control and Prevention, Atlanta, Georgia, USA
| | - Allon E. Moses
- Hadassah-Hebrew University Medical Center, Jerusalem, Israel
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Humar D, Datta V, Bast DJ, Beall B, De Azavedo JCS, Nizet V. Streptolysin S and necrotising infections produced by group G streptococcus. Lancet 2002; 359:124-9. [PMID: 11809255 DOI: 10.1016/s0140-6736(02)07371-3] [Citation(s) in RCA: 111] [Impact Index Per Article: 5.0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Indexed: 12/29/2022]
Abstract
BACKGROUND We encountered three patients with severe necrotising soft tissue infections due to beta-haemolytic group G streptococcus. Due to strong clinical similarities with invasive infections produced by group A streptococcus, we investigated a potential link of shared beta-haemolytic phenotype to disease pathogenesis. METHODS Hybridisation, DNA sequencing, targeted mutagenesis, and complementation studies were used to establish the genetic basis for group G streptococcus beta-haemolytic activity. The requirement of group G streptococcus beta-haemolysin in producing necrotising infection was examined in mice. FINDINGS Each patient had an underlying medical condition. beta-haemolytic group G streptococcus was the sole microbial isolate from debrided necrotic tissue. The group G streptococcus chromosome contained a homologue of the nine-gene group A streptococcus sag operon encoding the beta-haemolysin streptolysin S (SLS). Targeted mutagenesis of the putative SLS structural gene sagA in group G streptococcus eliminated beta-haemolytic activity. Mice injected subcutaneously with wild-type group A streptococcus or group G streptococcus developed an inflammatory lesion with high bacterial counts, marked neutrophil infiltration, and histopathological evidence of diffuse tissue necrosis. These changes were not found in mice injected with the isogenic group A streptococcus or group G streptococcus SLS-negative mutants. INTERPRETATION In patients with underlying medical conditions, beta-haemolytic group G streptococcus can produce necrotising soft tissue infections resembling those produced by group A streptococcus. The beta-haemolytic phenotype of group G streptococcus is produced by the exotoxin SLS, encoded by a functional homologue of the nine-gene group A streptococcus sag operon. SLS expression contributes to the pathogenesis of streptococcal necrotising soft tissue infection.
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Affiliation(s)
- Deepali Humar
- Department of Medicine, Division of Infectious Diseases, University of California, San Diego 92093, USA.
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