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Bessen DE, Beall BW, Hayes A, Huang W, DiChiara JM, Velusamy S, Tettelin H, Jolley KA, Fallon JT, Chochua S, Alobaidallah MSA, Higgs C, Barnett TC, Steemson JT, Proft T, Davies MR. Recombinational exchange of M-fibril and T-pilus genes generates extensive cell surface diversity in the global group A Streptococcus population. mBio 2024; 15:e0069324. [PMID: 38587426 PMCID: PMC11078000 DOI: 10.1128/mbio.00693-24] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/08/2024] [Accepted: 03/18/2024] [Indexed: 04/09/2024] Open
Abstract
Among genes present in all group A streptococci (GAS), those encoding M-fibril and T-pilus proteins display the highest levels of sequence diversity, giving rise to the two primary serological typing schemes historically used to define strain. A new genotyping scheme for the pilin adhesin and backbone genes is developed and, when combined with emm typing, provides an account of the global GAS strain population. Cluster analysis based on nucleotide sequence similarity assigns most T-serotypes to discrete pilin backbone sequence clusters, yet the established T-types correspond to only half the clusters. The major pilin adhesin and backbone sequence clusters yield 98 unique combinations, defined as "pilin types." Numerous horizontal transfer events that involve pilin or emm genes generate extensive antigenic and functional diversity on the bacterial cell surface and lead to the emergence of new strains. Inferred pilin genotypes applied to a meta-analysis of global population-based collections of pharyngitis and impetigo isolates reveal highly significant associations between pilin genotypes and GAS infection at distinct ecological niches, consistent with a role for pilin gene products in adaptive evolution. Integration of emm and pilin typing into open-access online tools (pubmlst.org) ensures broad utility for end-users wanting to determine the architecture of M-fibril and T-pilus genes from genome assemblies.IMPORTANCEPrecision in defining the variant forms of infectious agents is critical to understanding their population biology and the epidemiology of associated diseases. Group A Streptococcus (GAS) is a global pathogen that causes a wide range of diseases and displays a highly diverse cell surface due to the antigenic heterogeneity of M-fibril and T-pilus proteins which also act as virulence factors of varied functions. emm genotyping is well-established and highly utilized, but there is no counterpart for pilin genes. A global GAS collection provides the basis for a comprehensive pilin typing scheme, and online tools for determining emm and pilin genotypes are developed. Application of these tools reveals the expansion of structural-functional diversity among GAS via horizontal gene transfer, as evidenced by unique combinations of surface protein genes. Pilin and emm genotype correlations with superficial throat vs skin infection provide new insights on the molecular determinants underlying key ecological and epidemiological trends.
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Affiliation(s)
- Debra E. Bessen
- Department of Pathology, Microbiology, and Immunology, New York Medical College, Valhalla, New York, USA
| | - Bernard W. Beall
- Respiratory Disease Branch, National Center for Immunizations and Respiratory Diseases, Centers for Disease Control and Prevention (CDC), Atlanta, Georgia, USA
- Eagle Global Scientific, LLC, Atlanta, Georgia, USA
| | - Andrew Hayes
- Department of Microbiology and Immunology, The University of Melbourne at the Peter Doherty Institute for Infection and Immunity, Melbourne, Australia
| | - Weihua Huang
- Department of Pathology, Microbiology, and Immunology, New York Medical College, Valhalla, New York, USA
- Department of Pathology, Brody School of Medicine, Eastern Carolina University, Greenville, North Carolina, USA
| | - Jeanne M. DiChiara
- Department of Pathology, Microbiology, and Immunology, New York Medical College, Valhalla, New York, USA
| | - Srinivasan Velusamy
- Respiratory Disease Branch, National Center for Immunizations and Respiratory Diseases, Centers for Disease Control and Prevention (CDC), Atlanta, Georgia, USA
| | - Hervé Tettelin
- Department of Microbiology and Immunology, Institute for Genome Sciences, University of Maryland School of Medicine, Baltimore, Maryland, USA
| | - Keith A. Jolley
- Department of Biology, University of Oxford, Oxford, United Kingdom
| | - John T. Fallon
- Department of Pathology, Microbiology, and Immunology, New York Medical College, Valhalla, New York, USA
- Department of Pathology, Brody School of Medicine, Eastern Carolina University, Greenville, North Carolina, USA
| | - Sopio Chochua
- Respiratory Disease Branch, National Center for Immunizations and Respiratory Diseases, Centers for Disease Control and Prevention (CDC), Atlanta, Georgia, USA
| | - Mosaed S. A. Alobaidallah
- Department of Pathology, Microbiology, and Immunology, New York Medical College, Valhalla, New York, USA
| | - Charlie Higgs
- Department of Microbiology and Immunology, The University of Melbourne at the Peter Doherty Institute for Infection and Immunity, Melbourne, Australia
| | - Timothy C. Barnett
- The Marshall Centre for Infectious Diseases Research and Training, School of Biomedical Sciences, University of Western Australia, Nedlands, Australia
- Wesfarmers Centre of Vaccines and Infectious Diseases, Telethon Kids Institute, University of Western Australia, Nedlands, Australia
| | - John T. Steemson
- School of Biological Sciences, The University of Auckland, Auckland, New Zealand
| | - Thomas Proft
- School of Medical and Health Sciences, The University of Auckland, Auckland, New Zealand
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Proctor EJ, Frost HR, Satapathy S, Botquin G, Urbaniec J, Gorman J, De Oliveira DMP, McArthur J, Davies MR, Botteaux A, Smeesters P, Sanderson-Smith M. Molecular characterization of the interaction between human IgG and the M-related proteins from Streptococcus pyogenes. J Biol Chem 2024; 300:105623. [PMID: 38176650 PMCID: PMC10844976 DOI: 10.1016/j.jbc.2023.105623] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/24/2023] [Revised: 12/04/2023] [Accepted: 12/20/2023] [Indexed: 01/06/2024] Open
Abstract
Group A Streptococcal M-related proteins (Mrps) are dimeric α-helical-coiled-coil cell membrane-bound surface proteins. During infection, Mrp recruit the fragment crystallizable region of human immunoglobulin G via their A-repeat regions to the bacterial surface, conferring upon the bacteria enhanced phagocytosis resistance and augmented growth in human blood. However, Mrps show a high degree of sequence diversity, and it is currently not known whether this diversity affects the Mrp-IgG interaction. Herein, we report that diverse Mrps all bind human IgG subclasses with nanomolar affinity, with differences in affinity which ranged from 3.7 to 11.1 nM for mixed IgG. Using surface plasmon resonance, we confirmed Mrps display preferential IgG-subclass binding. All Mrps were found to have a significantly weaker affinity for IgG3 (p < 0.05) compared to all other IgG subclasses. Furthermore, plasma pulldown assays analyzed via Western blotting revealed that all Mrp were able to bind IgG in the presence of other serum proteins at both 25 °C and 37 °C. Finally, we report that dimeric Mrps bind to IgG with a 1:1 stoichiometry, enhancing our understanding of this important host-pathogen interaction.
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Affiliation(s)
- Emma-Jayne Proctor
- Molecular Horizons and School of Chemistry and Molecular Bioscience, University of Wollongong, Wollongong, Australia
| | - Hannah R Frost
- Molecular Bacteriology Laboratory, European Plotkins Institute for Vaccinology (EPIV), Université Libre de Bruxelles, Brussels, Belgium
| | - Sandeep Satapathy
- Molecular Horizons and School of Chemistry and Molecular Bioscience, University of Wollongong, Wollongong, Australia; The Broad Institute of MIT and Harvard, Cambridge, Massachusetts, USA
| | - Gwenaëlle Botquin
- Molecular Bacteriology Laboratory, European Plotkins Institute for Vaccinology (EPIV), Université Libre de Bruxelles, Brussels, Belgium
| | - Joanna Urbaniec
- Molecular Horizons and School of Chemistry and Molecular Bioscience, University of Wollongong, Wollongong, Australia
| | - Jody Gorman
- Molecular Horizons and School of Chemistry and Molecular Bioscience, University of Wollongong, Wollongong, Australia
| | - David M P De Oliveira
- The University of Queensland, School of Chemistry and Molecular Biosciences, Australian Infectious Diseases Research Centre, QLD, Australia
| | - Jason McArthur
- Molecular Horizons and School of Chemistry and Molecular Bioscience, University of Wollongong, Wollongong, Australia
| | - Mark R Davies
- Department of Microbiology and Immunology, at the Peter Doherty Institute for Infection and Immunity, The University of Melbourne, Victoria, Australia
| | - Anne Botteaux
- Molecular Bacteriology Laboratory, European Plotkins Institute for Vaccinology (EPIV), Université Libre de Bruxelles, Brussels, Belgium
| | - Pierre Smeesters
- Molecular Bacteriology Laboratory, European Plotkins Institute for Vaccinology (EPIV), Université Libre de Bruxelles, Brussels, Belgium
| | - Martina Sanderson-Smith
- Molecular Horizons and School of Chemistry and Molecular Bioscience, University of Wollongong, Wollongong, Australia.
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3
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Liu Q, Stadtmueller BM. SIgA structures bound to Streptococcus pyogenes M4 and human CD89 provide insights into host-pathogen interactions. Nat Commun 2023; 14:6726. [PMID: 37872175 PMCID: PMC10593759 DOI: 10.1038/s41467-023-42469-y] [Citation(s) in RCA: 1] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/21/2023] [Accepted: 10/12/2023] [Indexed: 10/25/2023] Open
Abstract
Immunoglobulin (Ig) A functions as monomeric IgA in the serum and Secretory (S) IgA in mucosal secretions. Host IgA Fc receptors (FcαRs), including human FcαR1/CD89, mediate IgA effector functions; however, human pathogen Streptococcus pyogenes has evolved surface-protein virulence factors, including M4, that also engage the CD89-binding site on IgA. Despite human mucosa serving as a reservoir for pathogens, SIgA interactions with CD89 and M4 remain poorly understood. Here we report cryo-EM structures of M4-SIgA and CD89-SIgA complexes, which unexpectedly reveal different SIgA-binding stoichiometry for M4 and CD89. Structural data, supporting experiments, and modeling indicate that copies of SIgA bound to S. pyogenes M4 will adopt similar orientations on the bacterium surface and leave one host FcαR binding site open. Results suggest unappreciated functional consequences associated with SIgA binding to host and bacterial FcαRs relevant to understanding host-microbe co-evolution, IgA effector functions and improving the outcomes of group A Streptococcus infection.
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Affiliation(s)
- Qianqiao Liu
- Department of Biochemistry, University of Illinois Urbana-Champaign, Urbana, Illinois, 61801, USA
| | - Beth M Stadtmueller
- Department of Biochemistry, University of Illinois Urbana-Champaign, Urbana, Illinois, 61801, USA.
- Department of Biomedical and Translational Sciences, Carle Illinois College of Medicine, University of Illinois Urbana-Champaign, Urbana, Illinois, 61801, USA.
- Carl R. Woese Institute for Genomic Biology, University of Illinois, Urbana, Illinois, 61801, USA.
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Liu Q, Stadtmueller BM. The Structures of Secretory IgA in complex with Streptococcus pyogenes M4 and human CD89 provide insights on mucosal host-pathogen interactions. BIORXIV : THE PREPRINT SERVER FOR BIOLOGY 2023:2023.04.21.537878. [PMID: 37662389 PMCID: PMC10473612 DOI: 10.1101/2023.04.21.537878] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Grants] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 09/05/2023]
Abstract
Immunoglobulin (Ig) A functions as monomeric IgA in the serum and Secretory (S) IgA in mucosal secretions. Host IgA Fc receptors (FcαRs), including human FcαR1/CD89, mediate IgA effector functions; however human pathogen Streptococcus pyogenes has evolved surface-protein virulence factors, including M4, that also engage the CD89 binding site on IgA. Despite human mucosa serving as a reservoir for pathogens, SIgA interactions with CD89 and M4 remain poorly understood. Here we report cryo-EM structures of M4-SIgA and CD89-SIgA complexes, which unexpectedly reveal different SIgA-binding stoichiometry for M4 and CD89. Structural data, supporting experiments, and modeling indicate that copies of SIgA bound to S. pyogenes M4 will adopt similar orientations on the bacterium surface and leave one host FcαR binding site open. Results suggest unappreciated functional consequences associated with SIgA binding to host and bacterial FcαRs relevant to understanding host-microbe co-evolution, IgA effector functions and to improving the outcomes of group A Streptococcus infection.
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Affiliation(s)
- Qianqiao Liu
- Department of Biochemistry, University of Illinois Urbana-Champaign, Urbana, Illinois 61801 USA
| | - Beth M Stadtmueller
- Department of Biochemistry, University of Illinois Urbana-Champaign, Urbana, Illinois 61801 USA
- Department of Biomedical and Translational Sciences, Carle Illinois College of Medicine, University of Illinois Urbana-Champaign, Urbana, Illinois 61801 USA
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5
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Frost H, Excler JL, Sriskandan S, Fulurija A. Correlates of immunity to Group A Streptococcus: a pathway to vaccine development. NPJ Vaccines 2023; 8:1. [PMID: 36650164 PMCID: PMC9844947 DOI: 10.1038/s41541-022-00593-8] [Citation(s) in RCA: 8] [Impact Index Per Article: 8.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/29/2022] [Accepted: 12/06/2022] [Indexed: 01/19/2023] Open
Abstract
Understanding immunity in humans to Group A Streptococcus (Strep A) is critical for the development of successful vaccines to prevent the morbidity and mortality attributed to Strep A infections. Despite decades of effort, no licensed vaccine against Strep A exists and immune correlates of protection are lacking; a major impediment to vaccine development. In the absence of a vaccine, we can take cues from the development of natural immunity to Strep A in humans to identify immune correlates of protection. The age stratification of incidence of acute Strep A infections, peaking in young children and waning in early adulthood, coincides with the development of specific immune responses. Therefore, understanding the immune mechanisms involved in natural protection from acute Strep A infection is critical to identifying immune correlates to inform vaccine development. This perspective summarises the findings from natural infection studies, existing assays of immunity to Strep A, and highlights the gaps in knowledge to guide the development of Strep A vaccines and associated correlates of protection.
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Affiliation(s)
- Hannah Frost
- grid.1058.c0000 0000 9442 535XMurdoch Children’s Research Institute, Melbourne, VIC Australia
| | - Jean-Louis Excler
- grid.30311.300000 0000 9629 885XInternational Vaccine Institute, Seoul, Republic of Korea
| | - Shiranee Sriskandan
- grid.7445.20000 0001 2113 8111Department of Infectious Disease, Imperial College London, London, UK ,grid.7445.20000 0001 2113 8111MRC Centre for Molecular Bacteriology & Infection, Imperial College London, London, UK
| | - Alma Fulurija
- grid.414659.b0000 0000 8828 1230Telethon Kid’s Institute, Perth, WA Australia ,grid.1012.20000 0004 1936 7910The University of Western Australia, Perth, WA Australia
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Chu HW, Chang KP, Yen WC, Liu HP, Chan XY, Liu CR, Hung CM, Wu CC. Identification of salivary autoantibodies as biomarkers of oral cancer with immunoglobulin A enrichment combined with affinity mass spectrometry. Proteomics 2023; 23:e2200321. [PMID: 36625099 DOI: 10.1002/pmic.202200321] [Citation(s) in RCA: 5] [Impact Index Per Article: 5.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/18/2022] [Revised: 01/02/2023] [Accepted: 01/05/2023] [Indexed: 01/11/2023]
Abstract
Globally, oral cavity squamous cell carcinoma (OSCC) is one of the most common fatal illnesses. Its high mortality is ascribed to the fact that the disease is often diagnosed at a late stage, which indicates an urgent need for approaches for the early detection of OSCC. The use of salivary autoantibodies (autoAbs) as OSCC biomarkers has numerous advantages such as easy access to saliva samples and efficient detection of autoAbs using well-established secondary reagents. To improve OSCC screening, we identified OSCC-associated autoAbs with the enrichment of salivary autoAbs combined with affinity mass spectrometry (MS). The salivary IgA of healthy individuals and OSCC patients was purified with peptide M-conjugated beads and then applied to immunoprecipitated antigens (Ags) in OSCC cells. Using tandem MS analysis and spectral counting-based quantitation, the level of 10 Ags increased in the OSCC group compared with the control group. Moreover, salivary levels of autoAbs to the 10 Ags were determined by a multiplexed bead-based immunoassay. Among them, seven were significantly higher in early-stage OSCC patients than in healthy individuals. A marker panel consisting of autoAbs to LMAN2, PTGR1, RAB13, and UQCRC2 was further developed to improve the early diagnosis of OSCC.
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Affiliation(s)
- Hao-Wei Chu
- Graduate Institute of Biomedical Sciences, College of Medicine, Chang Gung University, Taoyuan, Taiwan
| | - Kai-Ping Chang
- Department of Otolaryngology-Head and Neck Surgery, Chang Gung Memorial Hospital, Taoyuan, Taiwan.,Molecular Medicine Research Center, Chang Gung University, Taoyuan, Taiwan
| | - Wei-Chen Yen
- Department of Otolaryngology-Head and Neck Surgery, Chang Gung Memorial Hospital, Taoyuan, Taiwan.,Molecular Medicine Research Center, Chang Gung University, Taoyuan, Taiwan
| | - Hao-Ping Liu
- Department of Veterinary Medicine, College of Veterinary Medicine, National Chung Hsing University, Taichung, Taiwan
| | - Xiu-Ya Chan
- Graduate Institute of Biomedical Sciences, College of Medicine, Chang Gung University, Taoyuan, Taiwan.,Department of Medical Biotechnology and Laboratory Sciences, College of Medicine, Chang Gung University, Taoyuan, Taiwan
| | - Chiao-Rou Liu
- Graduate Institute of Biomedical Sciences, College of Medicine, Chang Gung University, Taoyuan, Taiwan.,Department of Medical Biotechnology and Laboratory Sciences, College of Medicine, Chang Gung University, Taoyuan, Taiwan
| | - Chu-Mi Hung
- Graduate Institute of Biomedical Sciences, College of Medicine, Chang Gung University, Taoyuan, Taiwan.,Department of Medical Biotechnology and Laboratory Sciences, College of Medicine, Chang Gung University, Taoyuan, Taiwan
| | - Chih-Ching Wu
- Graduate Institute of Biomedical Sciences, College of Medicine, Chang Gung University, Taoyuan, Taiwan.,Department of Otolaryngology-Head and Neck Surgery, Chang Gung Memorial Hospital, Taoyuan, Taiwan.,Molecular Medicine Research Center, Chang Gung University, Taoyuan, Taiwan.,Department of Medical Biotechnology and Laboratory Sciences, College of Medicine, Chang Gung University, Taoyuan, Taiwan.,Research Center for Emerging Viral Infections, College of Medicine, Chang Gung University, Taoyuan, Taiwan
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Ye J, Chen X. Current Promising Strategies against Antibiotic-Resistant Bacterial Infections. Antibiotics (Basel) 2022; 12:antibiotics12010067. [PMID: 36671268 PMCID: PMC9854991 DOI: 10.3390/antibiotics12010067] [Citation(s) in RCA: 9] [Impact Index Per Article: 4.5] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/27/2022] [Revised: 12/27/2022] [Accepted: 12/28/2022] [Indexed: 12/31/2022] Open
Abstract
Infections caused by antibiotic-resistant bacteria (ARB) are one of the major global health challenges of our time. In addition to developing new antibiotics to combat ARB, sensitizing ARB, or pursuing alternatives to existing antibiotics are promising options to counter antibiotic resistance. This review compiles the most promising anti-ARB strategies currently under development. These strategies include the following: (i) discovery of novel antibiotics by modification of existing antibiotics, screening of small-molecule libraries, or exploration of peculiar places; (ii) improvement in the efficacy of existing antibiotics through metabolic stimulation or by loading a novel, more efficient delivery systems; (iii) development of alternatives to conventional antibiotics such as bacteriophages and their encoded endolysins, anti-biofilm drugs, probiotics, nanomaterials, vaccines, and antibody therapies. Clinical or preclinical studies show that these treatments possess great potential against ARB. Some anti-ARB products are expected to become commercially available in the near future.
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The Retropepsin-Type Protease APRc as a Novel Ig-Binding Protein and Moonlighting Immune Evasion Factor of Rickettsia. mBio 2021; 12:e0305921. [PMID: 34872352 PMCID: PMC8649778 DOI: 10.1128/mbio.03059-21] [Citation(s) in RCA: 3] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/03/2022] Open
Abstract
Rickettsiae are obligate intracellular Gram-negative bacteria transmitted by arthropod vectors. Despite their reduced genomes, the function(s) of the majority of rickettsial proteins remains to be uncovered. APRc is a highly conserved retropepsin-type protease, suggested to act as a modulator of other rickettsial surface proteins with a role in adhesion/invasion. However, APRc’s function(s) in bacterial pathogenesis and virulence remains unknown. This study demonstrates that APRc targets host serum components, combining nonimmune immunoglobulin (Ig)-binding activity with resistance to complement-mediated killing. We confirmed nonimmune human IgG binding in extracts of different rickettsial species and intact bacteria. Our results revealed that the soluble domain of APRc is capable of binding to human (h), mouse, and rabbit IgG and different classes of human Ig (IgG, IgM, and IgA) in a concentration-dependent manner. APRc-hIgG interaction was confirmed with total hIgG and normal human serum. APRc-hIgG displayed a binding affinity in the micromolar range. We provided evidence of interaction preferentially through the Fab region and confirmed that binding is independent of catalytic activity. Mapping the APRc region responsible for binding revealed the segment between amino acids 157 and 166 as one of the interacting regions. Furthermore, we demonstrated that expression of the full-length protease in Escherichia coli is sufficient to promote resistance to complement-mediated killing and that interaction with IgG contributes to serum resistance. Our findings position APRc as a novel Ig-binding protein and a novel moonlighting immune evasion factor of Rickettsia, contributing to the arsenal of virulence factors utilized by these intracellular pathogens to aid in host colonization.
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Herrera AL, Chaussee MS. Signaling Peptide SpoV Is Essential for Streptococcus pyogenes Virulence, and Prophylaxis with Anti-SpoV Decreases Disease Severity. Microorganisms 2021; 9:microorganisms9112321. [PMID: 34835447 PMCID: PMC8619256 DOI: 10.3390/microorganisms9112321] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/01/2021] [Revised: 11/03/2021] [Accepted: 11/06/2021] [Indexed: 11/25/2022] Open
Abstract
Streptococcal peptide of virulence (SpoV) is a Streptococcus pyogenes (group A streptococcus (GAS))-specific peptide that is important for GAS survival in murine blood, and the expression of the virulence factors streptolysin O (slo) and streptolysin S (sagA). We used a spoV mutant in isolate MGAS315 to assess the contribution of the SpoV peptide to virulence by using a murine model of invasive disease and an ex vivo human model (Lancefield assay). We then used antibodies to SpoV in both models to evaluate their ability to decrease morbidity and mortality. Results showed that SpoV is essential for GAS virulence, and targeting the peptide has therapeutic potential.
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