1
|
Happonen L, Collin M. Immunomodulating Enzymes from Streptococcus pyogenes-In Pathogenesis, as Biotechnological Tools, and as Biological Drugs. Microorganisms 2024; 12:200. [PMID: 38258026 PMCID: PMC10818452 DOI: 10.3390/microorganisms12010200] [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: 12/19/2023] [Revised: 01/12/2024] [Accepted: 01/16/2024] [Indexed: 01/24/2024] Open
Abstract
Streptococcus pyogenes, or Group A Streptococcus, is an exclusively human pathogen that causes a wide variety of diseases ranging from mild throat and skin infections to severe invasive disease. The pathogenesis of S. pyogenes infection has been extensively studied, but the pathophysiology, especially of the more severe infections, is still somewhat elusive. One key feature of S. pyogenes is the expression of secreted, surface-associated, and intracellular enzymes that directly or indirectly affect both the innate and adaptive host immune systems. Undoubtedly, S. pyogenes is one of the major bacterial sources for immunomodulating enzymes. Major targets for these enzymes are immunoglobulins that are destroyed or modified through proteolysis or glycan hydrolysis. Furthermore, several enzymes degrade components of the complement system and a group of DNAses degrade host DNA in neutrophil extracellular traps. Additional types of enzymes interfere with cellular inflammatory and innate immunity responses. In this review, we attempt to give a broad overview of the functions of these enzymes and their roles in pathogenesis. For those enzymes where experimentally determined structures exist, the structural aspects of the enzymatic activity are further discussed. Lastly, we also discuss the emerging use of some of the enzymes as biotechnological tools as well as biological drugs and vaccines.
Collapse
Affiliation(s)
- Lotta Happonen
- Faculty of Medicine, Department of Clinical Sciences, Division of Infection Medicine, Lund University, SE-22184 Lund, Sweden
| | - Mattias Collin
- Faculty of Medicine, Department of Clinical Sciences, Division of Infection Medicine, Lund University, SE-22184 Lund, Sweden
| |
Collapse
|
2
|
Troese MJ, Burlet E, Cunningham MW, Alvarez K, Bentley R, Thomas N, Carwell S, Morefield GL. Group A Streptococcus Vaccine Targeting the Erythrogenic Toxins SpeA and SpeB Is Safe and Immunogenic in Rabbits and Does Not Induce Antibodies Associated with Autoimmunity. Vaccines (Basel) 2023; 11:1504. [PMID: 37766180 PMCID: PMC10534881 DOI: 10.3390/vaccines11091504] [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: 08/10/2023] [Revised: 09/15/2023] [Accepted: 09/18/2023] [Indexed: 09/29/2023] Open
Abstract
Group A streptococcus (GAS) is a global pathogen associated with significant morbidity and mortality for which there is currently no licensed vaccine. Vaccine development has been slow, mostly due to safety concerns regarding streptococcal antigens associated with autoimmunity and related complications. For a GAS vaccine to be safe, it must be ensured that the antigens used in the vaccine do not elicit an antibody response that can cross-react with host tissues. In this study, we evaluated the safety of our GAS vaccine candidate called VaxiStrep in New Zealand White rabbits. VaxiStrep is a recombinant fusion protein comprised of streptococcal pyrogenic exotoxin A (SpeA) and exotoxin B (SpeB), also known as erythrogenic toxins, adsorbed to an aluminum adjuvant. The vaccine elicited a robust immune response against the two toxins in the rabbits without any adverse events or toxicity. No signs of autoimmune pathology were detected in the rabbits' brains, hearts, and kidneys via immunohistochemistry, and serum antibodies did not cross-react with cardiac or neuronal tissue proteins associated with rheumatic heart disease or Sydenham chorea (SC). This study further confirms that VaxiStrep does not elicit autoantibodies and is safe to be tested in a first-in-human trial.
Collapse
Affiliation(s)
| | | | - Madeleine W. Cunningham
- Department of Microbiology and Immunology, University of Oklahoma Health Sciences Center, Oklahoma City, OK 73104, USA
| | - Kathy Alvarez
- Department of Microbiology and Immunology, University of Oklahoma Health Sciences Center, Oklahoma City, OK 73104, USA
| | - Rebecca Bentley
- Department of Microbiology and Immunology, University of Oklahoma Health Sciences Center, Oklahoma City, OK 73104, USA
| | | | | | | |
Collapse
|
3
|
Wilde S, Johnson AF, LaRock CN. Playing With Fire: Proinflammatory Virulence Mechanisms of Group A Streptococcus. Front Cell Infect Microbiol 2021; 11:704099. [PMID: 34295841 PMCID: PMC8290871 DOI: 10.3389/fcimb.2021.704099] [Citation(s) in RCA: 11] [Impact Index Per Article: 3.7] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/01/2021] [Accepted: 06/23/2021] [Indexed: 01/06/2023] Open
Abstract
Group A Streptococcus is an obligate human pathogen that is a major cause of infectious morbidity and mortality. It has a natural tropism for the oropharynx and skin, where it causes infections with excessive inflammation due to its expression of proinflammatory toxins and other virulence factors. Inflammation directly contributes to the severity of invasive infections, toxic shock syndrome, and the induction of severe post-infection autoimmune disease caused by autoreactive antibodies. This review discusses what is known about how the virulence factors of Group A Streptococcus induce inflammation and how this inflammation can promote disease. Understanding of streptococcal pathogenesis and the role of hyper-immune activation during infection may provide new therapeutic targets to treat the often-fatal outcome of severe disease.
Collapse
Affiliation(s)
- Shyra Wilde
- Microbiology and Molecular Genetics Program, Graduate Division of Biological and Biomedical Sciences, Laney Graduate School, Emory University, Atlanta, GA, United States
| | - Anders F Johnson
- Microbiology and Molecular Genetics Program, Graduate Division of Biological and Biomedical Sciences, Laney Graduate School, Emory University, Atlanta, GA, United States
| | - Christopher N LaRock
- Microbiology and Molecular Genetics Program, Graduate Division of Biological and Biomedical Sciences, Laney Graduate School, Emory University, Atlanta, GA, United States.,Department of Microbiology and Immunology, Division of Infectious Diseases, Department of Medicine, and Antibiotic Resistance Center, Emory University School of Medicine, Atlanta, GA, United States
| |
Collapse
|
4
|
Weckel A, Guilbert T, Lambert C, Plainvert C, Goffinet F, Poyart C, Méhats C, Fouet A. Streptococcus pyogenes infects human endometrium by limiting the innate immune response. J Clin Invest 2021; 131:130746. [PMID: 33320843 DOI: 10.1172/jci130746] [Citation(s) in RCA: 4] [Impact Index Per Article: 1.3] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/03/2019] [Accepted: 12/10/2020] [Indexed: 11/17/2022] Open
Abstract
Group A Streptococcus (GAS), a Gram-positive human-specific pathogen, yields 517,000 deaths annually worldwide, including 163,000 due to invasive infections and among them puerperal fever. Before efficient prophylactic measures were introduced, the mortality rate for mothers during childbirth was approximately 10%; puerperal fever still accounts for over 75,000 maternal deaths annually. Yet, little is known regarding the factors and mechanisms of GAS invasion and establishment in postpartum infection. We characterized the early steps of infection in an ex vivo infection model of the human decidua, the puerperal fever portal of entry. Coordinate analysis of GAS behavior and the immune response led us to demonstrate that (a) GAS growth was stimulated by tissue products; (b) GAS invaded tissue and killed approximately 50% of host cells within 2 hours, and these processes required SpeB protease and streptolysin O (SLO) activities, respectively; and (c) GAS impaired the tissue immune response. Immune impairment occurred both at the RNA level, with only partial induction of the innate immune response, and protein level, in an SLO- and SpeB-dependent manner. Our study indicates that efficient GAS invasion of the decidua and the restricted host immune response favored its propensity to develop rapid invasive infections in a gynecological-obstetrical context.
Collapse
Affiliation(s)
- Antonin Weckel
- Université de Paris, Institut Cochin, INSERM, U1016, CNRS, UMR8104, Paris, France.,Département Hospitalo-Universitaire Risk & Pregnancy, Port Royal Maternity, Paris, France
| | - Thomas Guilbert
- Université de Paris, Institut Cochin, INSERM, U1016, CNRS, UMR8104, Paris, France
| | - Clara Lambert
- Université de Paris, Institut Cochin, INSERM, U1016, CNRS, UMR8104, Paris, France.,Département Hospitalo-Universitaire Risk & Pregnancy, Port Royal Maternity, Paris, France
| | - Céline Plainvert
- Université de Paris, Institut Cochin, INSERM, U1016, CNRS, UMR8104, Paris, France.,Département Hospitalo-Universitaire Risk & Pregnancy, Port Royal Maternity, Paris, France.,Centre National de Référence des Streptocoques.,Hôpitaux Universitaires Paris Centre, Cochin, Assistance Publique Hôpitaux de Paris
| | - François Goffinet
- Département Hospitalo-Universitaire Risk & Pregnancy, Port Royal Maternity, Paris, France.,Faculté de Médecine, Université Paris Descartes, and.,Service de Gynécologie Obstétrique I, Maternité Port Royal, Assistance Publique-Hôpitaux de Paris, Paris, France
| | - Claire Poyart
- Université de Paris, Institut Cochin, INSERM, U1016, CNRS, UMR8104, Paris, France.,Département Hospitalo-Universitaire Risk & Pregnancy, Port Royal Maternity, Paris, France.,Centre National de Référence des Streptocoques.,Hôpitaux Universitaires Paris Centre, Cochin, Assistance Publique Hôpitaux de Paris
| | - Céline Méhats
- Université de Paris, Institut Cochin, INSERM, U1016, CNRS, UMR8104, Paris, France.,Département Hospitalo-Universitaire Risk & Pregnancy, Port Royal Maternity, Paris, France
| | - Agnès Fouet
- Université de Paris, Institut Cochin, INSERM, U1016, CNRS, UMR8104, Paris, France.,Département Hospitalo-Universitaire Risk & Pregnancy, Port Royal Maternity, Paris, France.,Centre National de Référence des Streptocoques
| |
Collapse
|
5
|
Dissecting Streptococcus pyogenes interaction with human. Arch Microbiol 2020; 202:2023-2032. [PMID: 32504132 DOI: 10.1007/s00203-020-01932-w] [Citation(s) in RCA: 2] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/12/2020] [Revised: 03/26/2020] [Accepted: 05/29/2020] [Indexed: 10/24/2022]
Abstract
Streptococcus pyogenes is a species of Gram-positive bacteria. It is also known as Group A Streptococcus (GAS) that causes pathogenesis to humans only. The GAS infection has several manifestations including invasive illness. Current research has linked the molecular modes of GAS virulence with substantial sequencing determinations for the isolation of genomes. These advances help to comprehend the molecular evolution resulting in the pandemic strains. Thus, it is indispensable to reconsider the philosophy that involves GAS pathogenesis. The recent investigations involve studying GAS in the nasopharynx and its capability to cause infection or asymptomatically reside in the host. These advances have been discussed in this article with an emphasis on the natural history of GAS and the evolutionary change in the pandemic strains. In addition, this review describes the unique functions for major pathogenicity determinants to comprehend their physiological effects.
Collapse
|
6
|
Piewngam P, Chiou J, Chatterjee P, Otto M. Alternative approaches to treat bacterial infections: targeting quorum-sensing. Expert Rev Anti Infect Ther 2020; 18:499-510. [PMID: 32243194 PMCID: PMC11032741 DOI: 10.1080/14787210.2020.1750951] [Citation(s) in RCA: 18] [Impact Index Per Article: 4.5] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/11/2020] [Accepted: 03/31/2020] [Indexed: 12/22/2022]
Abstract
Introduction: The emergence of multi- and pan-drug-resistant bacteria represents a global crisis that calls for the development of alternative anti-infective strategies. These comprise anti-virulence approaches, which target pathogenicity without exerting a bacteriostatic or bactericidal effect and are claimed to reduce the development of resistance. Because in many pathogens, quorum-sensing (QS) systems control the expression of virulence factors, interference with QS, or quorum-quenching, is often proposed as a strategy with a broad anti-virulence effect.Areas covered: We discuss the role and regulatory targets of QS control in selected Gram-positive and Gram-negative bacteria, focusing on those with clinical importance and QS control of virulence. We present the components of QS systems that form possible targets for the development of anti-virulence drugs and discuss recent research on quorum-quenching approaches to control bacterial infection.Expert opinion: While there has been extensive research on QS systems and quorum-quenching approaches, there is a paucity of in-vivo research using adequate animal models to substantiate applicability. In-vivo research on QS blockers needs to be intensified and optimized to use clinically relevant setups, in order to underscore that such drugs can be used effectively to overcome problems associated with the treatment of severe infections by antibiotic-resistant pathogens.
Collapse
Affiliation(s)
- Pipat Piewngam
- Pathogen Molecular Genetics Section, Laboratory of Bacteriology, National Institute of Allergy and Infectious Diseases, U.S. National Institutes of Health, 50 South Drive, Bethesda, Maryland 20814, USA
| | - Janice Chiou
- Pathogen Molecular Genetics Section, Laboratory of Bacteriology, National Institute of Allergy and Infectious Diseases, U.S. National Institutes of Health, 50 South Drive, Bethesda, Maryland 20814, USA
| | - Priyanka Chatterjee
- Pathogen Molecular Genetics Section, Laboratory of Bacteriology, National Institute of Allergy and Infectious Diseases, U.S. National Institutes of Health, 50 South Drive, Bethesda, Maryland 20814, USA
| | - Michael Otto
- Pathogen Molecular Genetics Section, Laboratory of Bacteriology, National Institute of Allergy and Infectious Diseases, U.S. National Institutes of Health, 50 South Drive, Bethesda, Maryland 20814, USA
| |
Collapse
|
7
|
Carothers KE, Liang Z, Mayfield J, Donahue DL, Lee M, Boggess B, Ploplis VA, Castellino FJ, Lee SW. The Streptococcal Protease SpeB Antagonizes the Biofilms of the Human Pathogen Staphylococcus aureus USA300 through Cleavage of the Staphylococcal SdrC Protein. J Bacteriol 2020; 202:e00008-20. [PMID: 32205460 PMCID: PMC7221255 DOI: 10.1128/jb.00008-20] [Citation(s) in RCA: 13] [Impact Index Per Article: 3.3] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/04/2020] [Accepted: 03/06/2020] [Indexed: 01/11/2023] Open
Abstract
Streptococcus pyogenes, or group A Streptococcus (GAS), is both a pathogen and an asymptomatic colonizer of human hosts and produces a large number of surface-expressed and secreted factors that contribute to a variety of infection outcomes. The GAS-secreted cysteine protease SpeB has been well studied for its effects on the human host; however, despite its broad proteolytic activity, studies on how this factor is utilized in polymicrobial environments are lacking. Here, we utilized various forms of SpeB protease to evaluate its antimicrobial and antibiofilm properties against the clinically important human colonizer Staphylococcus aureus, which occupies niches similar to those of GAS. For our investigation, we used a skin-tropic GAS strain, AP53CovS+, and its isogenic ΔspeB mutant to compare the production and activity of native SpeB protease. We also generated active and inactive forms of recombinant purified SpeB for functional studies. We demonstrate that SpeB exhibits potent biofilm disruption activity at multiple stages of S. aureus biofilm formation. We hypothesized that the surface-expressed adhesin SdrC in S. aureus was cleaved by SpeB, which contributed to the observed biofilm disruption. Indeed, we found that SpeB cleaved recombinant SdrC in vitro and in the context of the full S. aureus biofilm. Our results suggest an understudied role for the broadly proteolytic SpeB as an important factor for GAS colonization and competition with other microorganisms in its niche.IMPORTANCEStreptococcus pyogenes (GAS) causes a range of diseases in humans, ranging from mild to severe, and produces many virulence factors in order to be a successful pathogen. One factor produced by many GAS strains is the protease SpeB, which has been studied for its ability to cleave and degrade human proteins, an important factor in GAS pathogenesis. An understudied aspect of SpeB is the manner in which its broad proteolytic activity affects other microorganisms that co-occupy niches similar to that of GAS. The significance of the research reported herein is the demonstration that SpeB can degrade the biofilms of the human pathogen Staphylococcus aureus, which has important implications for how SpeB may be utilized by GAS to successfully compete in a polymicrobial environment.
Collapse
Affiliation(s)
- Katelyn E Carothers
- Department of Biological Sciences, University of Notre Dame, Notre Dame, Indiana, USA
- Eck Institute for Global Health, University of Notre Dame, Notre Dame, Indiana, USA
| | - Zhong Liang
- W. M. Keck Center for Transgene Research, University of Notre Dame, Notre Dame, Indiana, USA
| | - Jeffrey Mayfield
- W. M. Keck Center for Transgene Research, University of Notre Dame, Notre Dame, Indiana, USA
| | - Deborah L Donahue
- W. M. Keck Center for Transgene Research, University of Notre Dame, Notre Dame, Indiana, USA
| | - Mijoon Lee
- Department of Chemistry and Biochemistry, University of Notre Dame, Notre Dame, Indiana, USA
| | - Bill Boggess
- Department of Chemistry and Biochemistry, University of Notre Dame, Notre Dame, Indiana, USA
| | - Victoria A Ploplis
- W. M. Keck Center for Transgene Research, University of Notre Dame, Notre Dame, Indiana, USA
| | - Francis J Castellino
- W. M. Keck Center for Transgene Research, University of Notre Dame, Notre Dame, Indiana, USA
| | - Shaun W Lee
- Department of Biological Sciences, University of Notre Dame, Notre Dame, Indiana, USA
- Eck Institute for Global Health, University of Notre Dame, Notre Dame, Indiana, USA
- W. M. Keck Center for Transgene Research, University of Notre Dame, Notre Dame, Indiana, USA
| |
Collapse
|
8
|
Smith KP, Wang H, Durant TJ, Mathison BA, Sharp SE, Kirby JE, Long SW, Rhoads DD. Applications of Artificial Intelligence in Clinical Microbiology Diagnostic Testing. ACTA ACUST UNITED AC 2020. [DOI: 10.1016/j.clinmicnews.2020.03.006] [Citation(s) in RCA: 6] [Impact Index Per Article: 1.5] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 10/24/2022]
|
9
|
Abstract
Streptococcus pyogenes encodes multiple virulence factors and their presence is often related to the severity of the disease. We designed the system of four low-volume multiplex PCR reactions to detect genes encoding 20 virulence factors: spd3, sdc, sdaB, sdaD, speB, spyCEP, scpA, mac, sic, speL, speK, speM, speC, speI, speA, speH, speG, speJ, smeZ, and ssa. Classification of strains based on the virulence factors absence or presence correlates with PFGE MLST and emm typing results. The typing/detection system is fast and cost-effective, can be used to detect GAS virulence factors and as a rapid tool to effectively differentiate between strains.
Collapse
|
10
|
Tissue Tropism in Streptococcal Infection: Wild-Type M1T1 Group A Streptococcus Is Efficiently Cleared by Neutrophils Using an NADPH Oxidase-Dependent Mechanism in the Lung but Not in the Skin. Infect Immun 2019; 87:IAI.00527-19. [PMID: 31331954 DOI: 10.1128/iai.00527-19] [Citation(s) in RCA: 2] [Impact Index Per Article: 0.4] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/09/2019] [Accepted: 07/14/2019] [Indexed: 11/20/2022] Open
Abstract
Group A Streptococcus (GAS) commonly causes pharyngitis and skin infections. Little is known why streptococcal pharyngitis usually does not lead to pneumonia and why the skin is a favorite niche for GAS. To partially address these questions, the effectiveness of neutrophils in clearing wild-type (wt) M1T1 GAS strain MGAS2221 from the lung and from the skin was examined in murine models of intratracheal pneumonia and subcutaneous infection. Ninety-nine point seven percent of the MGAS2221 inoculum was cleared from the lungs of C57BL/6J mice at 24 h after inoculation, while there was no MGAS2221 clearance from skin infection sites. The bronchial termini had robust neutrophil infiltration, and depletion of neutrophils abolished MGAS2221 clearance from the lung. Phagocyte NADPH oxidase but not myeloperoxidase was required for MGAS2221 clearance. Thus, wt M1T1 GAS can be cleared by neutrophils using an NADPH oxidase-dependent mechanism in the lung. MGAS2221 induced robust neutrophil infiltration at the edge of skin infection sites and throughout infection sites at 24 h and 48 h after inoculation, respectively. Neutrophils within MGAS2221 infection sites had no nuclear staining. Skin infection sites of streptolysin S-deficient MGAS2221 ΔsagA were full of neutrophils with nuclear staining, whereas MGAS2221 ΔsagA infection was not cleared. Gp91phox knockout (KO) and control mice had similar GAS numbers at skin infection sites and similar abilities to select SpeB activity-negative (SpeBA-) variants. These results indicate that phagocyte NADPH oxidase-mediated GAS killing is compromised in the skin. Our findings support a model for GAS skin tropism in which GAS generates an anoxic niche to evade phagocyte NADPH oxidase-mediated clearance.
Collapse
|
11
|
Bernard PE, Kachroo P, Eraso JM, Zhu L, Madry JE, Linson SE, Ojeda Saavedra M, Cantu C, Musser JM, Olsen RJ. Polymorphisms in Regulator of Cov Contribute to the Molecular Pathogenesis of Serotype M28 Group A Streptococcus. THE AMERICAN JOURNAL OF PATHOLOGY 2019; 189:2002-2018. [PMID: 31369755 DOI: 10.1016/j.ajpath.2019.06.009] [Citation(s) in RCA: 7] [Impact Index Per Article: 1.4] [Reference Citation Analysis] [Abstract] [Track Full Text] [Subscribe] [Scholar Register] [Received: 05/10/2019] [Revised: 06/11/2019] [Accepted: 06/13/2019] [Indexed: 12/12/2022]
Abstract
Two-component systems (TCSs) are signal transduction proteins that enable bacteria to respond to external stimuli by altering the global transcriptome. Accessory proteins interact with TCSs to fine-tune their activity. In group A Streptococcus (GAS), regulator of Cov (RocA) is an accessory protein that functions with the control of virulence regulator/sensor TCS, which regulates approximately 15% of the GAS transcriptome. Whole-genome sequencing analysis of serotype M28 GAS strains collected from invasive infections in humans identified a higher number of missense (amino acid-altering) and nonsense (protein-truncating) polymorphisms in rocA than expected. We hypothesized that polymorphisms in RocA alter the global transcriptome and virulence of serotype M28 GAS. We used naturally occurring clinical isolates with rocA polymorphisms (n = 48), an isogenic rocA deletion mutant strain, and five isogenic rocA polymorphism mutant strains to perform genome-wide transcript analysis (RNA sequencing), in vitro virulence factor assays, and mouse and nonhuman primate pathogenesis studies to test this hypothesis. Results demonstrated that polymorphisms in rocA result in either a subtle transcriptome change, causing a wild-type-like virulence phenotype, or a substantial transcriptome change, leading to a significantly increased virulence phenotype. Each polymorphism had a unique effect on the global GAS transcriptome. Taken together, our data show that naturally occurring polymorphisms in one gene encoding an accessory protein can significantly alter the global transcriptome and virulence phenotype of GAS, an important human pathogen.
Collapse
Affiliation(s)
- Paul E Bernard
- Center for Molecular and Translational Human Infectious Diseases Research, Department of Pathology and Genomic Medicine, Houston Methodist Research Institute and Houston Methodist Hospital, Houston, Texas; Texas A&M Health Science Center College of Medicine, Bryan, Texas
| | - Priyanka Kachroo
- Center for Molecular and Translational Human Infectious Diseases Research, Department of Pathology and Genomic Medicine, Houston Methodist Research Institute and Houston Methodist Hospital, Houston, Texas
| | - Jesus M Eraso
- Center for Molecular and Translational Human Infectious Diseases Research, Department of Pathology and Genomic Medicine, Houston Methodist Research Institute and Houston Methodist Hospital, Houston, Texas
| | - Luchang Zhu
- Center for Molecular and Translational Human Infectious Diseases Research, Department of Pathology and Genomic Medicine, Houston Methodist Research Institute and Houston Methodist Hospital, Houston, Texas
| | - Jessica E Madry
- Center for Molecular and Translational Human Infectious Diseases Research, Department of Pathology and Genomic Medicine, Houston Methodist Research Institute and Houston Methodist Hospital, Houston, Texas
| | - Sarah E Linson
- Center for Molecular and Translational Human Infectious Diseases Research, Department of Pathology and Genomic Medicine, Houston Methodist Research Institute and Houston Methodist Hospital, Houston, Texas
| | - Matthew Ojeda Saavedra
- Center for Molecular and Translational Human Infectious Diseases Research, Department of Pathology and Genomic Medicine, Houston Methodist Research Institute and Houston Methodist Hospital, Houston, Texas
| | - Concepcion Cantu
- Center for Molecular and Translational Human Infectious Diseases Research, Department of Pathology and Genomic Medicine, Houston Methodist Research Institute and Houston Methodist Hospital, Houston, Texas
| | - James M Musser
- Center for Molecular and Translational Human Infectious Diseases Research, Department of Pathology and Genomic Medicine, Houston Methodist Research Institute and Houston Methodist Hospital, Houston, Texas; Department of Pathology and Laboratory Medicine, Weill Cornell Medical College, New York, New York
| | - Randall J Olsen
- Center for Molecular and Translational Human Infectious Diseases Research, Department of Pathology and Genomic Medicine, Houston Methodist Research Institute and Houston Methodist Hospital, Houston, Texas; Texas A&M Health Science Center College of Medicine, Bryan, Texas; Department of Pathology and Laboratory Medicine, Weill Cornell Medical College, New York, New York.
| |
Collapse
|
12
|
Ermert D, Ram S, Laabei M. The hijackers guide to escaping complement: Lessons learned from pathogens. Mol Immunol 2019; 114:49-61. [PMID: 31336249 DOI: 10.1016/j.molimm.2019.07.018] [Citation(s) in RCA: 29] [Impact Index Per Article: 5.8] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/04/2019] [Revised: 07/15/2019] [Accepted: 07/16/2019] [Indexed: 02/07/2023]
Abstract
Pathogens that invade the human host are confronted by a multitude of defence mechanisms aimed at preventing colonization, dissemination and proliferation. The most frequent outcome of this interaction is microbial elimination, in which the complement system plays a major role. Complement, an essential feature of the innate immune machinery, rapidly identifies and marks pathogens for efficient removal. Consequently, this creates a selective pressure for microbes to evolve strategies to combat complement, permitting host colonization and access to resources. All successful pathogens have developed mechanisms to resist complement activity which are intimately aligned with their capacity to cause disease. In this review, we describe the successful methods various pathogens use to evade complement activation, shut down inflammatory signalling through complement, circumvent opsonisation and override terminal pathway lysis. This review summarizes how pathogens undermine innate immunity: 'The Hijackers Guide to Complement'.
Collapse
Affiliation(s)
- David Ermert
- Department of Preclinical Research, BioInvent International AB, Lund, Sweden; Department of Translational Medicine, Division of Medical Protein Chemistry, Lund University, Malmö, Sweden
| | - Sanjay Ram
- Department of Medicine, Division of Infectious Diseases and Immunology, University of Massachusetts Medical School, Worcester, MA, USA
| | - Maisem Laabei
- Department of Biology and Biochemistry, University of Bath, Bath, United Kingdom.
| |
Collapse
|
13
|
Do H, Makthal N, VanderWal AR, Saavedra MO, Olsen RJ, Musser JM, Kumaraswami M. Environmental pH and peptide signaling control virulence of Streptococcus pyogenes via a quorum-sensing pathway. Nat Commun 2019; 10:2586. [PMID: 31197146 PMCID: PMC6565748 DOI: 10.1038/s41467-019-10556-8] [Citation(s) in RCA: 29] [Impact Index Per Article: 5.8] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/02/2019] [Accepted: 05/14/2019] [Indexed: 12/20/2022] Open
Abstract
Bacteria control gene expression in concert with their population density by a process called quorum sensing, which is modulated by bacterial chemical signals and environmental factors. In the human pathogen Streptococcus pyogenes, production of secreted virulence factor SpeB is controlled by a quorum-sensing pathway and environmental pH. The quorum-sensing pathway consists of a secreted leaderless peptide signal (SIP), and its cognate receptor RopB. Here, we report that the SIP quorum-sensing pathway has a pH-sensing mechanism operative through a pH-sensitive histidine switch located at the base of the SIP-binding pocket of RopB. Environmental acidification induces protonation of His144 and reorganization of hydrogen bonding networks in RopB, which facilitates SIP recognition. The convergence of two disparate signals in the SIP signaling pathway results in induction of SpeB production and increased bacterial virulence. Our findings provide a model for investigating analogous crosstalk in other microorganisms.
Collapse
Affiliation(s)
- Hackwon Do
- Center for Molecular and Translational Human Infectious Diseases Research, Houston Methodist Research Institute, Houston, TX, 77030, USA
- Department of Pathology and Genomic Medicine, Houston Methodist Hospital, Houston, TX, 77030, USA
| | - Nishanth Makthal
- Center for Molecular and Translational Human Infectious Diseases Research, Houston Methodist Research Institute, Houston, TX, 77030, USA
- Department of Pathology and Genomic Medicine, Houston Methodist Hospital, Houston, TX, 77030, USA
| | - Arica R VanderWal
- Center for Molecular and Translational Human Infectious Diseases Research, Houston Methodist Research Institute, Houston, TX, 77030, USA
- Department of Pathology and Genomic Medicine, Houston Methodist Hospital, Houston, TX, 77030, USA
| | - Matthew Ojeda Saavedra
- Center for Molecular and Translational Human Infectious Diseases Research, Houston Methodist Research Institute, Houston, TX, 77030, USA
- Department of Pathology and Genomic Medicine, Houston Methodist Hospital, Houston, TX, 77030, USA
| | - Randall J Olsen
- Center for Molecular and Translational Human Infectious Diseases Research, Houston Methodist Research Institute, Houston, TX, 77030, USA
- Department of Pathology and Genomic Medicine, Houston Methodist Hospital, Houston, TX, 77030, USA
- Department of Pathology and Laboratory Medicine, Weill Medical College of Cornell University, New York, NY, 10021, USA
| | - James M Musser
- Center for Molecular and Translational Human Infectious Diseases Research, Houston Methodist Research Institute, Houston, TX, 77030, USA
- Department of Pathology and Genomic Medicine, Houston Methodist Hospital, Houston, TX, 77030, USA
- Department of Pathology and Laboratory Medicine, Weill Medical College of Cornell University, New York, NY, 10021, USA
| | - Muthiah Kumaraswami
- Center for Molecular and Translational Human Infectious Diseases Research, Houston Methodist Research Institute, Houston, TX, 77030, USA.
- Department of Pathology and Genomic Medicine, Houston Methodist Hospital, Houston, TX, 77030, USA.
| |
Collapse
|
14
|
Integrated analysis of population genomics, transcriptomics and virulence provides novel insights into Streptococcus pyogenes pathogenesis. Nat Genet 2019; 51:548-559. [PMID: 30778225 DOI: 10.1038/s41588-018-0343-1] [Citation(s) in RCA: 50] [Impact Index Per Article: 10.0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/12/2018] [Accepted: 12/21/2018] [Indexed: 12/22/2022]
Abstract
Streptococcus pyogenes causes 700 million human infections annually worldwide, yet, despite a century of intensive effort, there is no licensed vaccine against this bacterium. Although a number of large-scale genomic studies of bacterial pathogens have been published, the relationships among the genome, transcriptome, and virulence in large bacterial populations remain poorly understood. We sequenced the genomes of 2,101 emm28 S. pyogenes invasive strains, from which we selected 492 phylogenetically diverse strains for transcriptome analysis and 50 strains for virulence assessment. Data integration provided a novel understanding of the virulence mechanisms of this model organism. Genome-wide association study, expression quantitative trait loci analysis, machine learning, and isogenic mutant strains identified and confirmed a one-nucleotide indel in an intergenic region that significantly alters global transcript profiles and ultimately virulence. The integrative strategy that we used is generally applicable to any microbe and may lead to new therapeutics for many human pathogens.
Collapse
|
15
|
Abstract
Group A Streptococcus (GAS) causes common pharyngitis and skin infections and occasional severe invasive infections. This review describes the recent progress on the pathogenesis of hypervirulent GAS. CovRS mutations are frequent among invasive GAS isolates and lead to hypervirulence. GAS CovRS mutants can be selected in vivo by neutrophils. The role of protease SpeB in source-sink dynamics of wild-type GAS and hypervirulent variants is discussed. Streptolysin S and PAF acetylhydrolase Sse critically and synergistically contribute to the inhibition of neutrophil recruitment by GAS CovS mutants. CovS mutations in emm3 GAS lead to the vascular invasion and enhance systemic GAS dissemination.
Collapse
|
16
|
Chiang-Ni C, Shi YA, Lai CH, Chiu CH. Cytotoxicity and Survival Fitness of Invasive covS Mutant of Group A Streptococcus in Phagocytic Cells. Front Microbiol 2018; 9:2592. [PMID: 30425702 PMCID: PMC6218877 DOI: 10.3389/fmicb.2018.02592] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.2] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/10/2018] [Accepted: 10/11/2018] [Indexed: 11/27/2022] Open
Abstract
Group A streptococci (GAS) with spontaneous mutations in the CovR/CovS regulatory system are more invasive and related to severe manifestations. GAS can replicate inside phagocytic cells; therefore, phagocytic cells could serve as the niche to select invasive covS mutants. Nonetheless, the encapsulated covS mutant is resistant to phagocytosis. The fate of intracellular covS mutant in phagocytic cells and whether the intracellular covS mutant contributes to invasive infections are unclear. In this study, capsule-deficient (cap-) strains were utilized to study how intracellular bacteria interacted with phagocytic cells. Results from the competitive infection model showed that the cap-covS mutant had better survival fitness than the cap- wild-type strain in the PMA-activated U937 cells. In addition, the cap-covS mutant caused more cell damages than the cap- wild-type strain and encapsulated covS mutant. Furthermore, treatments with infected cells with clindamycin to inhibit the intracellular bacteria growth was more effective to reduce bacterial toxicity than utilized penicillin to kill the extracellular bacteria. These results not only suggest that the covS mutant could be selected from the intracellular niche of phagocytic cells but also indicating that inactivating or killing intracellular GAS may be critical to prevent invasive infection.
Collapse
Affiliation(s)
- Chuan Chiang-Ni
- Department of Microbiology and Immunology, College of Medicine, Chang Gung University, Taoyuan, Taiwan.,Graduate Institute of Biomedical Sciences, College of Medicine, Chang Gung University, Taoyuan, Taiwan.,Molecular Infectious Disease Research Center, Chang Gung Memorial Hospital, Taoyuan, Taiwan
| | - Yong-An Shi
- Graduate Institute of Biomedical Sciences, College of Medicine, Chang Gung University, Taoyuan, Taiwan
| | - Chih-Ho Lai
- Department of Microbiology and Immunology, College of Medicine, Chang Gung University, Taoyuan, Taiwan.,Graduate Institute of Biomedical Sciences, College of Medicine, Chang Gung University, Taoyuan, Taiwan.,Molecular Infectious Disease Research Center, Chang Gung Memorial Hospital, Taoyuan, Taiwan
| | - Cheng-Hsun Chiu
- Graduate Institute of Biomedical Sciences, College of Medicine, Chang Gung University, Taoyuan, Taiwan.,Molecular Infectious Disease Research Center, Chang Gung Memorial Hospital, Taoyuan, Taiwan.,Department of Pediatrics, Chang Gung Children's Hospital, Taoyuan, Taiwan
| |
Collapse
|
17
|
RocA Has Serotype-Specific Gene Regulatory and Pathogenesis Activities in Serotype M28 Group A Streptococcus. Infect Immun 2018; 86:IAI.00467-18. [PMID: 30126898 DOI: 10.1128/iai.00467-18] [Citation(s) in RCA: 13] [Impact Index Per Article: 2.2] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/15/2018] [Accepted: 08/13/2018] [Indexed: 12/21/2022] Open
Abstract
Serotype M28 group A streptococcus (GAS) is a common cause of infections such as pharyngitis ("strep throat") and necrotizing fasciitis ("flesh-eating" disease). Relatively little is known about the molecular mechanisms underpinning M28 GAS pathogenesis. Whole-genome sequencing studies of M28 GAS strains recovered from patients with invasive infections found an unexpectedly high number of missense (amino acid-changing) and nonsense (protein-truncating) polymorphisms in rocA (regulator of Cov), leading us to hypothesize that altered RocA activity contributes to M28 GAS molecular pathogenesis. To test this hypothesis, an isogenic rocA deletion mutant strain was created. Transcriptome sequencing (RNA-seq) analysis revealed that RocA inactivation significantly alters the level of transcripts for 427 and 323 genes at mid-exponential and early stationary growth phases, respectively, including genes for 41 transcription regulators and 21 virulence factors. In contrast, RocA transcriptomes from other GAS M protein serotypes are much smaller and include fewer transcription regulators. The rocA mutant strain had significantly increased secreted activity of multiple virulence factors and grew to significantly higher colony counts under acid stress in vitro RocA inactivation also significantly increased GAS virulence in a mouse model of necrotizing myositis. Our results demonstrate that RocA is an important regulator of transcription regulators and virulence factors in M28 GAS and raise the possibility that naturally occurring polymorphisms in rocA in some fashion contribute to human invasive infections caused by M28 GAS strains.
Collapse
|
18
|
Phenotypic Variation in the Group A Streptococcus Due to Natural Mutation of the Accessory Protein-Encoding Gene rocA. mSphere 2018; 3:3/5/e00519-18. [PMID: 30333182 PMCID: PMC6193603 DOI: 10.1128/msphere.00519-18] [Citation(s) in RCA: 8] [Impact Index Per Article: 1.3] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/20/2022] Open
Abstract
Populations of a bacterial pathogen, whether recovered from a single patient or from a worldwide study, are often a heterogeneous mix of genetically and phenotypically divergent strains. Such heterogeneity is of value in changing environments and arises via mechanisms such as gene gain or gene mutation. Here, we identify an isolate of serotype M12 group A Streptococcus (GAS) (Streptococcus pyogenes) that has a natural mutation in rocA, which encodes an accessory protein to the virulence-regulating two-component system CovR/CovS (CovR/S). Disruption of RocA activity results in the differential expression of multiple GAS virulence factors, including the anti-phagocytic hyaluronic acid capsule and the chemokine protease SpyCEP. While some of our data regarding RocA-regulated genes overlaps with previous studies, which were performed with isolates of alternate GAS serotypes, some variability was also observed. Perhaps as a consequence of this alternate regulatory activity, we discovered that the contribution of RocA to the ability of the M12 isolate to survive and proliferate in human blood ex vivo is opposite that previously observed in M1, M3, and M18 GAS strains. Specifically, rocA mutation reduced, rather than enhanced, survival of the isolate. Finally, we also present data from an analysis of rocA transcription and show that rocA is transcribed in both mono- and polycistronic mRNAs. In aggregate, our data provide insight into the important regulatory role of RocA and into the mechanisms and consequences of GAS phenotypic heterogeneity.IMPORTANCE This study investigates the regulatory and phenotypic consequences of a naturally occurring mutation in a strain of the bacterial pathogen the group A Streptococcus (Streptococcus pyogenes). We show that this mutation, which occurs in a regulator-encoding gene, rocA, leads to altered virulence factor expression and reduces the ability of this isolate to survive in human blood. Critically, the blood survival phenotype and the assortment of genes regulated by RocA differ compared to previous studies into RocA activity. The data are consistent with there being strain- or serotype-specific variability in RocA function. Given that phenotypic variants can lead to treatment failures and escape from preventative regimes, our data provide information with regard to a mechanism of phenotypic variation in a prevalent Gram-positive pathogen.
Collapse
|
19
|
Laabei M, Ermert D. Catch Me if You Can: Streptococcus pyogenes Complement Evasion Strategies. J Innate Immun 2018; 11:3-12. [PMID: 30269134 DOI: 10.1159/000492944] [Citation(s) in RCA: 32] [Impact Index Per Article: 5.3] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/02/2018] [Accepted: 08/16/2018] [Indexed: 12/27/2022] Open
Abstract
The human host has evolved elaborate protection mechanisms to prevent infection from the billions of microorganisms to which it host is exposed and is home. One of these systems, complement, is an evolutionary ancient arm of innate immunity essential for combatting bacterial infection. Complement permits the efficient labelling of bacteria with opsonins, supports phagocytosis, and facilitates phagocyte recruitment to the site of infection through the production of chemoattractants. However, it is by no means perfect, and certain organisms engage in an evolutionary arms race with the host where complement has become a major target to promote immune evasion. Streptococcus pyogenes is a major human pathogen that causes significant morbidity and mortality globally. S. pyogenes is also a member of an elite group of bacterial pathogens possessing a sophisticated arsenal of virulence determinants capable of interfering with complement. In this review, we focus on these complement evasins, their mechanism of action, and their importance in disease progression. Finally, we highlight new therapeutic options for fighting S. pyogenes, by interfering with one of its main mechanisms of complement evasion.
Collapse
|
20
|
Balasubramanian N, Varatharaju G, Shanmugaiah V, Balakrishnan K, Thirunarayan MA. Molecular Cloning and Docking of speB Gene Encoding Cysteine Protease With Antibiotic Interaction in Streptococcus pyogenes NBMKU12 From the Clinical Isolates. Front Microbiol 2018; 9:1658. [PMID: 30131773 PMCID: PMC6091236 DOI: 10.3389/fmicb.2018.01658] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/23/2018] [Accepted: 07/03/2018] [Indexed: 11/13/2022] Open
Abstract
Streptococcus pyogenes causes a variety of diseases ranging from mild diseases to severe invasive infections which result in significant morbidity and mortality. This study focuses on the antibiotic resistance of S. pyogenes and their interaction with cysteine protease. Around 36 beta-hemolytic isolates were collected from the clinical lab, of which seven isolates (19.4%) were identified as Streptococcus pyogenes. One of the seven isolates was collected from a urinary tract infection, which was identified by antibody agglutination and MALTI-TOF-MS, and it is designated as S. pyogenes NBMKU12. Around 8.3 to 66.6 % of the isolates were found to be resistant to one or more antimicrobial agents, especially, penicillin-G resistance was exhibited by 29.1% of the isolates. In the NBMKU12 isolate, the beta lactem (TEM) gene was detected among the 13 antibiotic genes for which it was tested. Furthermore, when analysis for presence of 13 virulence genes were carried out in NBMKU12 isolate, only speJ and speB were detected. The speB (streptococcal pyrogenic exotoxin B) encoding cysteine protease gene was cloned. This was followed by performing DNA sequencing to understand the putative cysteine protease interaction with antibiotics, inhibitors, and substrate. The speB gene consists of 1197 nucleotides and encodes a protein with multiple domains, including a signal peptide (aa 1-22), an inhibitor region (aa 27-156), and a catalytic cysteine domain (aa 160-367). The signal peptide cleavage site is predicted between Ala22 and Asn23. The putative 398 amino acid residues were found to have a theoretical pI of 8.76 and a molecular mass of 43,204.36 Da. The tested culture supernatants of NBMKU12 isolate exhibited the proteolytic activity against casein, papaya and pineapple used as substrates. The proteolytic activity suggests the expression of speB gene. Molecular docking analysis of cysteine protease showed that erythromycin (bond length 2.41 Å), followed by chloramphenicol (2.51 Å), exhibited a strong interaction; while penicillin-G (3.24 Å) exhibited a weak interaction, and this factor could be considered as a cause for penicillin-G resistance. The present study contributes to a better understanding of speB gene encoding cysteine protease, antibiotic resistance, and their interaction in the isolate, S. pyogenes NBMKU12. The antibiotics and cysteine protease interaction study confirms the resistance or sensitivity of S. pyogenes. Hence, it could be hypothesized that the isolate NBMKU12 is resistant to most of the tested antibiotics, and this resistance might be a cause for mutation.
Collapse
Affiliation(s)
- Natesan Balasubramanian
- Department of Immunology, School of Biological Sciences, Madurai Kamaraj University, Madurai, India
| | - Govintharaj Varatharaju
- Department of Microbial Technology, School of Biological Sciences, Madurai Kamaraj University, Madurai, India
| | - Vellasamy Shanmugaiah
- Department of Microbial Technology, School of Biological Sciences, Madurai Kamaraj University, Madurai, India
| | - Karuppiah Balakrishnan
- Department of Immunology, School of Biological Sciences, Madurai Kamaraj University, Madurai, India
| | | |
Collapse
|
21
|
Makthal N, Do H, VanderWal AR, Olsen RJ, Musser JM, Kumaraswami M. Signaling by a Conserved Quorum Sensing Pathway Contributes to Growth Ex Vivo and Oropharyngeal Colonization of Human Pathogen Group A Streptococcus. Infect Immun 2018; 86:e00169-18. [PMID: 29531135 PMCID: PMC5913841 DOI: 10.1128/iai.00169-18] [Citation(s) in RCA: 10] [Impact Index Per Article: 1.7] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/02/2018] [Accepted: 03/04/2018] [Indexed: 02/06/2023] Open
Abstract
Bacterial virulence factor production is a highly coordinated process. The temporal pattern of bacterial gene expression varies in different host anatomic sites to overcome niche-specific challenges. The human pathogen group A streptococcus (GAS) produces a potent secreted protease, SpeB, that is crucial for pathogenesis. Recently, we discovered that a quorum sensing pathway comprised of a leaderless short peptide, SpeB-inducing peptide (SIP), and a cytosolic global regulator, RopB, controls speB expression in concert with bacterial population density. The SIP signaling pathway is active in vivo and contributes significantly to GAS invasive infections. In the current study, we investigated the role of the SIP signaling pathway in GAS-host interactions during oropharyngeal colonization. The SIP signaling pathway is functional during growth ex vivo in human saliva. SIP-mediated speB expression plays a crucial role in GAS colonization of the mouse oropharynx. GAS employs a distinct pattern of SpeB production during growth ex vivo in saliva that includes a transient burst of speB expression during early stages of growth coupled with sustained levels of secreted SpeB protein. SpeB production aids GAS survival by degrading LL37, an abundant human antimicrobial peptide. We found that SIP signaling occurs during growth in human blood ex vivo. Moreover, the SIP signaling pathway is critical for GAS survival in blood. SIP-dependent speB regulation is functional in strains of diverse emm types, indicating that SIP signaling is a conserved virulence regulatory mechanism. Our discoveries have implications for future translational studies.
Collapse
Affiliation(s)
- Nishanth Makthal
- Center for Molecular and Translational Human Infectious Diseases Research, Houston Methodist Research Institute, and Department of Pathology and Genomic Medicine, Houston Methodist Hospital, Houston, Texas, USA
| | - Hackwon Do
- Center for Molecular and Translational Human Infectious Diseases Research, Houston Methodist Research Institute, and Department of Pathology and Genomic Medicine, Houston Methodist Hospital, Houston, Texas, USA
| | - Arica R VanderWal
- Center for Molecular and Translational Human Infectious Diseases Research, Houston Methodist Research Institute, and Department of Pathology and Genomic Medicine, Houston Methodist Hospital, Houston, Texas, USA
| | - Randall J Olsen
- Center for Molecular and Translational Human Infectious Diseases Research, Houston Methodist Research Institute, and Department of Pathology and Genomic Medicine, Houston Methodist Hospital, Houston, Texas, USA
- Department of Pathology and Laboratory Medicine, Weill Medical College of Cornell University, New York, New York, USA
| | - James M Musser
- Center for Molecular and Translational Human Infectious Diseases Research, Houston Methodist Research Institute, and Department of Pathology and Genomic Medicine, Houston Methodist Hospital, Houston, Texas, USA
- Department of Pathology and Laboratory Medicine, Weill Medical College of Cornell University, New York, New York, USA
| | - Muthiah Kumaraswami
- Center for Molecular and Translational Human Infectious Diseases Research, Houston Methodist Research Institute, and Department of Pathology and Genomic Medicine, Houston Methodist Hospital, Houston, Texas, USA
| |
Collapse
|
22
|
Do H, Makthal N, VanderWal AR, Rettel M, Savitski MM, Peschek N, Papenfort K, Olsen RJ, Musser JM, Kumaraswami M. Leaderless secreted peptide signaling molecule alters global gene expression and increases virulence of a human bacterial pathogen. Proc Natl Acad Sci U S A 2017; 114:E8498-E8507. [PMID: 28923955 PMCID: PMC5635878 DOI: 10.1073/pnas.1705972114] [Citation(s) in RCA: 38] [Impact Index Per Article: 5.4] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/09/2023] Open
Abstract
Successful pathogens use complex signaling mechanisms to monitor their environment and reprogram global gene expression during specific stages of infection. Group A Streptococcus (GAS) is a major human pathogen that causes significant disease burden worldwide. A secreted cysteine protease known as streptococcal pyrogenic exotoxin B (SpeB) is a key virulence factor that is produced abundantly during infection and is critical for GAS pathogenesis. Although identified nearly a century ago, the molecular basis for growth phase control of speB gene expression remains unknown. We have discovered that GAS uses a previously unknown peptide-mediated intercellular signaling system to control SpeB production, alter global gene expression, and enhance virulence. GAS produces an eight-amino acid leaderless peptide [SpeB-inducing peptide (SIP)] during high cell density and uses the secreted peptide for cell-to-cell signaling to induce population-wide speB expression. The SIP signaling pathway includes peptide secretion, reimportation into the cytosol, and interaction with the intracellular global gene regulator Regulator of Protease B (RopB), resulting in SIP-dependent modulation of DNA binding and regulatory activity of RopB. Notably, SIP signaling causes differential expression of ∼14% of GAS core genes. Several genes that encode toxins and other virulence genes that enhance pathogen dissemination and infection are significantly up-regulated. Using three mouse infection models, we show that the SIP signaling pathway is active during infection and contributes significantly to GAS pathogenesis at multiple host anatomic sites. Together, our results delineate the molecular mechanisms involved in a previously undescribed virulence regulatory pathway of an important human pathogen and suggest new therapeutic strategies.
Collapse
Affiliation(s)
- Hackwon Do
- Center for Molecular and Translational Human Infectious Diseases Research, Houston Methodist Research Institute, Houston Methodist Hospital, Houston, TX 77030
- Department of Pathology and Genomic Medicine, Houston Methodist Hospital, Houston, TX 77030
| | - Nishanth Makthal
- Center for Molecular and Translational Human Infectious Diseases Research, Houston Methodist Research Institute, Houston Methodist Hospital, Houston, TX 77030
- Department of Pathology and Genomic Medicine, Houston Methodist Hospital, Houston, TX 77030
| | - Arica R VanderWal
- Center for Molecular and Translational Human Infectious Diseases Research, Houston Methodist Research Institute, Houston Methodist Hospital, Houston, TX 77030
- Department of Pathology and Genomic Medicine, Houston Methodist Hospital, Houston, TX 77030
| | - Mandy Rettel
- Genome Biology Unit, European Molecular Biology Laboratory, 69117 Heidelberg, Germany
| | - Mikhail M Savitski
- Genome Biology Unit, European Molecular Biology Laboratory, 69117 Heidelberg, Germany
| | - Nikolai Peschek
- Munich Center for Integrated Protein Science, Department of Microbiology, Ludwig Maximilians University of Munich, 82152 Martinsried, Germany
| | - Kai Papenfort
- Munich Center for Integrated Protein Science, Department of Microbiology, Ludwig Maximilians University of Munich, 82152 Martinsried, Germany
| | - Randall J Olsen
- Center for Molecular and Translational Human Infectious Diseases Research, Houston Methodist Research Institute, Houston Methodist Hospital, Houston, TX 77030
- Department of Pathology and Genomic Medicine, Houston Methodist Hospital, Houston, TX 77030
- Department of Pathology and Laboratory Medicine, Weill Medical College of Cornell University, New York, NY 10021
| | - James M Musser
- Center for Molecular and Translational Human Infectious Diseases Research, Houston Methodist Research Institute, Houston Methodist Hospital, Houston, TX 77030
- Department of Pathology and Genomic Medicine, Houston Methodist Hospital, Houston, TX 77030
- Department of Pathology and Laboratory Medicine, Weill Medical College of Cornell University, New York, NY 10021
| | - Muthiah Kumaraswami
- Center for Molecular and Translational Human Infectious Diseases Research, Houston Methodist Research Institute, Houston Methodist Hospital, Houston, TX 77030;
- Department of Pathology and Genomic Medicine, Houston Methodist Hospital, Houston, TX 77030
| |
Collapse
|
23
|
Ly AT, Noto JP, Walwyn OL, Tanz RR, Shulman ST, Kabat W, Bessen DE. Differences in SpeB protease activity among group A streptococci associated with superficial, invasive, and autoimmune disease. PLoS One 2017; 12:e0177784. [PMID: 28545045 PMCID: PMC5435240 DOI: 10.1371/journal.pone.0177784] [Citation(s) in RCA: 4] [Impact Index Per Article: 0.6] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/22/2016] [Accepted: 05/03/2017] [Indexed: 11/19/2022] Open
Abstract
The secreted cysteine proteinase SpeB is an important virulence factor of group A streptococci (GAS), whereby SpeB activity varies widely among strains. To establish the degree to which SpeB activity correlates with disease, GAS organisms were recovered from patients with pharyngitis, impetigo, invasive disease or acute rheumatic fever (ARF), and selected for analysis using rigorous sampling criteria; >300 GAS isolates were tested for SpeB activity by casein digestion assays, and each GAS isolate was scored as a SpeB-producer or non-producer. Highly significant statistical differences (p < 0.01) in SpeB production are observed between GAS recovered from patients with ARF (41.5% SpeB-non-producers) compared to pharyngitis (20.5%), invasive disease (16.7%), and impetigo (5.5%). SpeB activity differences between pharyngitis and impetigo isolates are also significant, whereas pharyngitis versus invasive isolates show no significant difference. The disproportionately greater number of SpeB-non-producers among ARF-associated isolates may indicate an altered transcriptional program for many rheumatogenic strains and/or a protective role for SpeB in GAS-triggered autoimmunity.
Collapse
Affiliation(s)
- Anhphan T. Ly
- Department of Microbiology and Immunology, New York Medical College, Valhalla, New York, United States of America
| | - John P. Noto
- Department of Microbiology and Immunology, New York Medical College, Valhalla, New York, United States of America
| | - Odaelys L. Walwyn
- Department of Microbiology and Immunology, New York Medical College, Valhalla, New York, United States of America
| | - Robert R. Tanz
- Department of Pediatrics, Northwestern University Feinberg School of Medicine and Ann & Robert H. Lurie Children's Hospital, Chicago, Illinois, United States of America
| | - Stanford T. Shulman
- Department of Pediatrics, Northwestern University Feinberg School of Medicine and Ann & Robert H. Lurie Children's Hospital, Chicago, Illinois, United States of America
| | - William Kabat
- Department of Pediatrics, Northwestern University Feinberg School of Medicine and Ann & Robert H. Lurie Children's Hospital, Chicago, Illinois, United States of America
| | - Debra E. Bessen
- Department of Microbiology and Immunology, New York Medical College, Valhalla, New York, United States of America
| |
Collapse
|
24
|
Burlet E, HogenEsch H, Dunham A, Morefield G. Evaluation of the Potency, Neutralizing Antibody Response, and Stability of a Recombinant Fusion Protein Vaccine for Streptococcus pyogenes. AAPS JOURNAL 2017; 19:875-881. [DOI: 10.1208/s12248-017-0069-5] [Citation(s) in RCA: 7] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Track Full Text] [Subscribe] [Scholar Register] [Received: 01/04/2017] [Accepted: 02/25/2017] [Indexed: 11/30/2022]
|
25
|
Wilkening RV, Federle MJ. Evolutionary Constraints Shaping Streptococcus pyogenes-Host Interactions. Trends Microbiol 2017; 25:562-572. [PMID: 28216292 DOI: 10.1016/j.tim.2017.01.007] [Citation(s) in RCA: 27] [Impact Index Per Article: 3.9] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/15/2016] [Revised: 12/15/2016] [Accepted: 01/23/2017] [Indexed: 02/07/2023]
Abstract
Research on the Gram-positive human-restricted pathogen Streptococcus pyogenes (Group A Streptococcus, GAS) has long focused on invasive illness, the most severe manifestations of GAS infection. Recent advances in descriptions of molecular mechanisms of GAS virulence, coupled with massive sequencing efforts to isolate genomes, have allowed the field to better understand the molecular and evolutionary changes leading to pandemic strains. These findings suggest that it is necessary to rethink the dogma involving GAS pathogenesis, and that the most productive avenues for research going forward may be investigations into GAS in its 'normal' habitat, the nasopharynx, and its ability to either live with its host in an asymptomatic lifestyle or as an agent of superficial infections. This review will consider these advances, focusing on the natural history of GAS, the evolution of pandemic strains, and novel roles for several key virulence factors that may allow the field to better understand their physiological role.
Collapse
Affiliation(s)
- Reid V Wilkening
- Department of Microbiology and Immunology, University of Illinois at Chicago, Chicago, IL 60607, USA; Center for Biomolecular Sciences, University of Illinois at Chicago, Chicago, IL 60607, USA
| | - Michael J Federle
- Department of Medicinal Chemistry and Pharmacognosy, University of Illinois at Chicago, Chicago, IL 60607, USA; Center for Biomolecular Sciences, University of Illinois at Chicago, Chicago, IL 60607, USA.
| |
Collapse
|
26
|
Null Mutations of Group A Streptococcus Orphan Kinase RocA: Selection in Mouse Infection and Comparison with CovS Mutations in Alteration of In Vitro and In Vivo Protease SpeB Expression and Virulence. Infect Immun 2016; 85:IAI.00790-16. [PMID: 27795364 DOI: 10.1128/iai.00790-16] [Citation(s) in RCA: 16] [Impact Index Per Article: 2.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/15/2016] [Accepted: 10/17/2016] [Indexed: 12/19/2022] Open
Abstract
Group A Streptococcus (GAS) acquires mutations of the virulence regulator CovRS in human and mouse infections, and these mutations result in the upregulation of virulence genes and the downregulation of the protease SpeB. To identify in vivo mutants with novel phenotypes, GAS isolates from infected mice were screened by enzymatic assays for SpeB and the platelet-activating factor acetylhydrolase Sse, and a new type of variant that had enhanced Sse expression and normal levels of SpeB production was identified (the variants had a phenotype referred to as enhanced Sse activity [SseA+] and normal SpeB activity [SpeBA+]). SseA+ SpeBA+ variants had transcript levels of CovRS-controlled virulence genes comparable to those of a covS mutant but had no covRS mutations. Genome resequencing of an SseA+ SpeBA+ isolate identified a C605A nonsense mutation in orphan kinase gene rocA, and 6 other SseA+ SpeBA+ isolates also had nonsense mutations or small indels in rocA RocA and CovS mutants had similar levels of enhancement of the expression of CovRS-controlled virulence genes at the exponential growth phase; however, mutations of RocA but not mutations of CovS did not result in the downregulation of speB transcription at stationary growth phase or in subcutaneous infection of mice. GAS with RocA and CovS mutations caused greater enhancement of the expression of hasA than spyCEP in mouse skin infection than wild-type GAS did. RocA mutants ranked between wild-type GAS and CovS mutants in skin invasion, inhibition of neutrophil recruitment, and virulence in subcutaneous infection of mice. Thus, GAS RocA mutants can be selected in subcutaneous infections in mice and exhibit gene expression patterns and virulences distinct from those of CovS mutants. The findings provide novel information for understanding GAS fitness mutations in vivo, virulence gene regulation, in vivo gene expression, and virulence.
Collapse
|
27
|
Sarkar P, Sumby P. Regulatory gene mutation: a driving force behind group a Streptococcus strain- and serotype-specific variation. Mol Microbiol 2016; 103:576-589. [PMID: 27868255 DOI: 10.1111/mmi.13584] [Citation(s) in RCA: 28] [Impact Index Per Article: 3.5] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Accepted: 11/16/2016] [Indexed: 01/13/2023]
Abstract
Data from multiple bacterial pathogens are consistent with regulator-encoding genes having higher mutation frequencies than the genome average. Such mutations drive both strain- and type- (e.g., serotype, haplotype) specific phenotypic heterogeneity, and may challenge public health due to the potential of variants to circumvent established treatment and/or preventative regimes. Here, using the human bacterial pathogen the group A Streptococcus (GAS; S. pyogenes) as a model organism, we review the types and regulatory-, phenotypic-, and disease-specific consequences of naturally occurring regulatory gene mutations. Strain-specific regulator mutations that will be discussed include examples that transform isolates into hyper-invasive forms by enhancing expression of immunomodulatory virulence factors, and examples that promote asymptomatic carriage of the organism. The discussion of serotype-specific regulator mutations focuses on serotype M3 GAS isolates, and how the identified rewiring of regulatory networks in this serotype may be contributing to a decades old epidemiological association of M3 isolates with particularly severe invasive infections. We conclude that mutation plays an outsized role in GAS pathogenesis and has clinical relevance. Given the phenotypic variability associated with regulatory gene mutations, the rapid examination of these genes in infecting isolates may inform with respect to potential patient complications and treatment options.
Collapse
Affiliation(s)
- Poulomee Sarkar
- Department of Microbiology & Immunology, University of Nevada, Reno School of Medicine, Reno, Nevada, USA
| | - Paul Sumby
- Department of Microbiology & Immunology, University of Nevada, Reno School of Medicine, Reno, Nevada, USA
| |
Collapse
|
28
|
Uhlmann J, Siemens N, Kai-Larsen Y, Fiedler T, Bergman P, Johansson L, Norrby-Teglund A. Phosphoglycerate Kinase—A Novel Streptococcal Factor Involved in Neutrophil Activation and Degranulation. J Infect Dis 2016; 214:1876-1883. [DOI: 10.1093/infdis/jiw450] [Citation(s) in RCA: 10] [Impact Index Per Article: 1.3] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/26/2016] [Accepted: 09/16/2016] [Indexed: 01/14/2023] Open
|
29
|
Feng W, Liu M, Chen DG, Yiu R, Fang FC, Lei B. Contemporary Pharyngeal and Invasive emm1 and Invasive emm12 Group A Streptococcus Isolates Exhibit Similar In Vivo Selection for CovRS Mutants in Mice. PLoS One 2016; 11:e0162742. [PMID: 27611332 PMCID: PMC5017694 DOI: 10.1371/journal.pone.0162742] [Citation(s) in RCA: 11] [Impact Index Per Article: 1.4] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/04/2016] [Accepted: 08/26/2016] [Indexed: 12/15/2022] Open
Abstract
Group A Streptococcus (GAS) causes diverse infections ranging from common pharyngitis to rare severe invasive infections. Invasive GAS isolates can have natural mutations in the virulence regulator CovRS, which result in enhanced expression of multiple virulence genes, suppressed the expression of the protease SpeB, and increased virulence. It is believed that CovRS mutations arise during human infections with GAS carrying wild-type CovRS and are not transmissible. CovRS mutants of invasive GAS of the emm1 genotype arise readily during experimental infection in mice. It is possible that invasive GAS arises from pharyngeal GAS through rare genetic mutations that confer the capacity of mutated GAS to acquire covRS mutations during infection. The objective of this study was to determine whether contemporary pharyngeal emm1 GAS isolates have a reduced propensity to acquire CovRS mutations in vivo compared with invasive emm1 GAS and whether emm3, emm12, and emm28 GAS acquire CovRS mutants in mouse infection. The propensity of invasive and pharyngeal emm1 and invasive emm3, emm12, and emm28 SpeBA+ isolates to acquire variants with the SpeBA- phenotype was determined during subcutaneous infection of mice. The majority of both invasive and pharyngeal emm1 SpeBA+ isolates and two of three emm12 isolates, but not emm3 and emm28 isolates, were found to acquire SpeBA- variants during skin infection in mice. All analyzed SpeBA- variants of emm1 and emm12 GAS from the mouse infection acquired covRS mutations and produced more platelet-activating factor acetylhydrolase SsE. Thus, contemporary invasive and pharyngeal emm1 GAS isolates and emm12 GAS have a similar capacity to acquire covRS mutations in vivo. The rarity of severe invasive infections caused by GAS does not appear to be attributable to a reduced ability of pharyngeal isolates to acquire CovRS mutations.
Collapse
Affiliation(s)
- Wenchao Feng
- Department of Microbiology and Immunology, Montana State University, Bozeman, Montana 59718, United States of America
| | - Mengyao Liu
- Department of Microbiology and Immunology, Montana State University, Bozeman, Montana 59718, United States of America
| | - Daniel G. Chen
- Department of Microbiology and Immunology, Montana State University, Bozeman, Montana 59718, United States of America
| | - Rossana Yiu
- Harborview Medical Center Clinical Microbiology Laboratory and University of Washington School of Medicine, Seattle, Washington, United States of America
| | - Ferric C. Fang
- Harborview Medical Center Clinical Microbiology Laboratory and University of Washington School of Medicine, Seattle, Washington, United States of America
| | - Benfang Lei
- Department of Microbiology and Immunology, Montana State University, Bozeman, Montana 59718, United States of America
- * E-mail:
| |
Collapse
|