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Popoff MR. Overview of Bacterial Protein Toxins from Pathogenic Bacteria: Mode of Action and Insights into Evolution. Toxins (Basel) 2024; 16:182. [PMID: 38668607 PMCID: PMC11054074 DOI: 10.3390/toxins16040182] [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: 02/16/2024] [Revised: 03/29/2024] [Accepted: 03/30/2024] [Indexed: 04/29/2024] Open
Abstract
Bacterial protein toxins are secreted by certain bacteria and are responsible for mild to severe diseases in humans and animals. They are among the most potent molecules known, which are active at very low concentrations. Bacterial protein toxins exhibit a wide diversity based on size, structure, and mode of action. Upon recognition of a cell surface receptor (protein, glycoprotein, and glycolipid), they are active either at the cell surface (signal transduction, membrane damage by pore formation, or hydrolysis of membrane compound(s)) or intracellularly. Various bacterial protein toxins have the ability to enter cells, most often using an endocytosis mechanism, and to deliver the effector domain into the cytosol, where it interacts with an intracellular target(s). According to the nature of the intracellular target(s) and type of modification, various cellular effects are induced (cell death, homeostasis modification, cytoskeleton alteration, blockade of exocytosis, etc.). The various modes of action of bacterial protein toxins are illustrated with representative examples. Insights in toxin evolution are discussed.
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Affiliation(s)
- Michel R Popoff
- Unité des Toxines Bactériennes, Institut Pasteur, Université Paris Cité, CNRS UMR 2001 INSERM U1306, F-75015 Paris, France
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Savin A, Anderson EE, Dyzenhaus S, Podkowik M, Shopsin B, Pironti A, Torres VJ. Staphylococcus aureus senses human neutrophils via PerR to coordinate the expression of the toxin LukAB. Infect Immun 2024; 92:e0052623. [PMID: 38235972 PMCID: PMC10863418 DOI: 10.1128/iai.00526-23] [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: 12/18/2023] [Accepted: 12/20/2023] [Indexed: 01/19/2024] Open
Abstract
Staphylococcus aureus is a gram-positive pathogen that poses a major health concern, in part due to its large array of virulence factors that allow infection and evasion of the immune system. One of these virulence factors is the bicomponent pore-forming leukocidin LukAB. The regulation of lukAB expression is not completely understood, especially in the presence of immune cells such as human polymorphonuclear neutrophils (hPMNs). Here, we screened for transcriptional regulators of lukAB during the infection of primary hPMNs. We uncovered that PerR, a peroxide sensor, is vital for hPMN-mediated induction of lukAB and that PerR upregulates cytotoxicity during the infection of hPMNs. Exposure of S. aureus to hydrogen peroxide (H2O2) alone also results in increased lukAB promoter activity, a phenotype dependent on PerR. Collectively, our data suggest that S. aureus uses PerR to sense the H2O2 produced by hPMNs to stimulate the expression of lukAB, allowing the bacteria to withstand these critical innate immune cells.IMPORTANCEStaphylococcus aureus utilizes a diverse set of virulence factors, such as leukocidins, to subvert human neutrophils, but how these toxins are regulated is incompletely defined. Here, we identified the peroxide-sensitive repressor, PerR, as a required protein involved in the induction of lukAB in the presence of primary human neutrophils, a phenotype directly linked to the ability of PerR to sense H2O2. Thus, we show that S. aureus coordinates sensing and resistance to oxidative stress with toxin production to promote pathogen survival.
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Affiliation(s)
- Avital Savin
- Department of Microbiology, New York University Grossman School of Medicine, New York, New York, USA
- Department of Biology, New York University, New York, New York, USA
| | - Exene E. Anderson
- Department of Microbiology, New York University Grossman School of Medicine, New York, New York, USA
| | - Sophie Dyzenhaus
- Department of Microbiology, New York University Grossman School of Medicine, New York, New York, USA
| | - Magdalena Podkowik
- Antimicrobial-Resistant Pathogens Program, New York University Grossman School of Medicine, New York, New York, USA
- Division of Infectious Diseases, Department of Medicine, New York University Grossman School of Medicine, New York, New York, USA
| | - Bo Shopsin
- Department of Microbiology, New York University Grossman School of Medicine, New York, New York, USA
- Antimicrobial-Resistant Pathogens Program, New York University Grossman School of Medicine, New York, New York, USA
- Division of Infectious Diseases, Department of Medicine, New York University Grossman School of Medicine, New York, New York, USA
| | - Alejandro Pironti
- Department of Microbiology, New York University Grossman School of Medicine, New York, New York, USA
- Antimicrobial-Resistant Pathogens Program, New York University Grossman School of Medicine, New York, New York, USA
| | - Victor J. Torres
- Department of Microbiology, New York University Grossman School of Medicine, New York, New York, USA
- Department of Host-Microbe Interactions, St. Jude Children’s Research Hospital, Memphis, Tennessee, USA
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Li X, Li G, Huang H, Wan P, Lu Y, Li Z, Xie L, Xiong W, Zeng Z. The occurrence and contamination of optrA-positive methicillin-resistant Staphylococcus aureus from duck farms in Guangdong, China. J Glob Antimicrob Resist 2023; 35:86-92. [PMID: 37689309 DOI: 10.1016/j.jgar.2023.08.015] [Citation(s) in RCA: 1] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/25/2022] [Revised: 07/28/2023] [Accepted: 08/21/2023] [Indexed: 09/11/2023] Open
Abstract
OBJECTIVES Staphylococcus aureus, especially methicillin-resistant S. aureus (MRSA), is an important zoonotic microorganism that increasingly causes public health concern worldwide. The objective of this study was to determine the prevalence and transmission of S. aureus in duck farms and evaluate its antimicrobial resistance and genetic characteristics. METHODS The samples associated with ducks, feeders, and the environment were collected on 14 duck farms from four areas in Guangdong, China, from 2020 to 2021. All isolates were subjected to antimicrobial susceptibility testing. A comprehensive epidemiological survey of S. aureus was conducted by S. aureus protein A typing and whole-genome sequencing. RESULTS A total of 560 samples were collected. The prevalence rate of MRSA among ducks (8.1%, 11 of 135) was higher compared with that in environmental samples. OptrA-positive ST398-t034 MRSA were first detected from duck farms in China. A total of 79.3% (34 of 46) S. aureus isolates showed multidrug-resistant phenotypes. Notably, some isolates carried multidrug-resistant genes encoding macrolide-lincosamide-streptogramin B, pleuromutilin-pleuromutilin-streptogramin A, and oxazolidinone. Analysis of the virulence genes revealed that the MRSA isolates carried genes encoding gamma-hemolysin, enterotoxin, and leukocidin. ST9-t899 is a primary clonal lineage among duck- and environment-associated MRSA. Single-nucleotide polymorphism analysis showed the potential contamination relationship of optrA-positive ST2308 MRSA isolates carrying the gamma-hemolysin genes and the leukocidin virulence genes between airborne dust and sick ducks. CONCLUSION The contamination of MRSA, especially optrA-positive MRSA, between food animals and the environment is a growing public health concern worldwide. Based on One Health principles, continuous surveillance of MRSA is urgently needed.
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Affiliation(s)
- Xiaoshen Li
- Guangdong Provincial Key Laboratory of Veterinary Pharmaceutics Development and Safety Evaluation, College of Veterinary Medicine, South China Agricultural University, Guangzhou, China; National Risk Assessment Laboratory for Antimicrobial Resistance of Animal Original Bacteria, South China Agricultural University, Guangzhou, China; National Laboratory of Safety Evaluation (Environmental Assessment) of Veterinary Drugs, South China Agricultural University, Guangzhou, China
| | - Guihua Li
- Guangdong Provincial Key Laboratory of Veterinary Pharmaceutics Development and Safety Evaluation, College of Veterinary Medicine, South China Agricultural University, Guangzhou, China; National Risk Assessment Laboratory for Antimicrobial Resistance of Animal Original Bacteria, South China Agricultural University, Guangzhou, China; National Laboratory of Safety Evaluation (Environmental Assessment) of Veterinary Drugs, South China Agricultural University, Guangzhou, China
| | - Honghao Huang
- Guangdong Provincial Key Laboratory of Veterinary Pharmaceutics Development and Safety Evaluation, College of Veterinary Medicine, South China Agricultural University, Guangzhou, China; National Risk Assessment Laboratory for Antimicrobial Resistance of Animal Original Bacteria, South China Agricultural University, Guangzhou, China; National Laboratory of Safety Evaluation (Environmental Assessment) of Veterinary Drugs, South China Agricultural University, Guangzhou, China
| | - Peng Wan
- Guangdong Provincial Key Laboratory of Veterinary Pharmaceutics Development and Safety Evaluation, College of Veterinary Medicine, South China Agricultural University, Guangzhou, China; National Risk Assessment Laboratory for Antimicrobial Resistance of Animal Original Bacteria, South China Agricultural University, Guangzhou, China; National Laboratory of Safety Evaluation (Environmental Assessment) of Veterinary Drugs, South China Agricultural University, Guangzhou, China
| | - Yixing Lu
- Guangdong Provincial Key Laboratory of Veterinary Pharmaceutics Development and Safety Evaluation, College of Veterinary Medicine, South China Agricultural University, Guangzhou, China; National Risk Assessment Laboratory for Antimicrobial Resistance of Animal Original Bacteria, South China Agricultural University, Guangzhou, China; National Laboratory of Safety Evaluation (Environmental Assessment) of Veterinary Drugs, South China Agricultural University, Guangzhou, China
| | - Zhi Li
- Guangdong Provincial Key Laboratory of Veterinary Pharmaceutics Development and Safety Evaluation, College of Veterinary Medicine, South China Agricultural University, Guangzhou, China; National Risk Assessment Laboratory for Antimicrobial Resistance of Animal Original Bacteria, South China Agricultural University, Guangzhou, China; National Laboratory of Safety Evaluation (Environmental Assessment) of Veterinary Drugs, South China Agricultural University, Guangzhou, China
| | - Longfei Xie
- Guangdong Provincial Key Laboratory of Veterinary Pharmaceutics Development and Safety Evaluation, College of Veterinary Medicine, South China Agricultural University, Guangzhou, China; National Risk Assessment Laboratory for Antimicrobial Resistance of Animal Original Bacteria, South China Agricultural University, Guangzhou, China; National Laboratory of Safety Evaluation (Environmental Assessment) of Veterinary Drugs, South China Agricultural University, Guangzhou, China
| | - Wenguang Xiong
- Guangdong Provincial Key Laboratory of Veterinary Pharmaceutics Development and Safety Evaluation, College of Veterinary Medicine, South China Agricultural University, Guangzhou, China; National Risk Assessment Laboratory for Antimicrobial Resistance of Animal Original Bacteria, South China Agricultural University, Guangzhou, China; National Laboratory of Safety Evaluation (Environmental Assessment) of Veterinary Drugs, South China Agricultural University, Guangzhou, China
| | - Zhenling Zeng
- Guangdong Provincial Key Laboratory of Veterinary Pharmaceutics Development and Safety Evaluation, College of Veterinary Medicine, South China Agricultural University, Guangzhou, China; National Risk Assessment Laboratory for Antimicrobial Resistance of Animal Original Bacteria, South China Agricultural University, Guangzhou, China; National Laboratory of Safety Evaluation (Environmental Assessment) of Veterinary Drugs, South China Agricultural University, Guangzhou, China.
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Ilmain JK, Perelman SS, Panepinto MC, Irnov I, Coudray N, Samhadaneh N, Pironti A, Ueberheide B, Ekiert DC, Bhabha G, Torres VJ. Unlatching of the stem domains in the Staphylococcus aureus pore-forming leukocidin LukAB influences toxin oligomerization. J Biol Chem 2023; 299:105321. [PMID: 37802313 PMCID: PMC10665946 DOI: 10.1016/j.jbc.2023.105321] [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: 05/23/2023] [Revised: 09/22/2023] [Accepted: 09/27/2023] [Indexed: 10/08/2023] Open
Abstract
Staphylococcus aureus (S. aureus) is a serious global pathogen that causes a diverse range of invasive diseases. S. aureus utilizes a family of pore-forming toxins, known as bi-component leukocidins, to evade the host immune response and promote infection. Among these is LukAB (leukocidin A/leukocidin B), a toxin that assembles into an octameric β-barrel pore in the target cell membrane, resulting in host cell death. The established cellular receptor for LukAB is CD11b of the Mac-1 complex. Here, we show that hydrogen voltage-gated channel 1 is also required for the cytotoxicity of all major LukAB variants. We demonstrate that while each receptor is sufficient to recruit LukAB to the plasma membrane, both receptors are required for maximal lytic activity. Why LukAB requires two receptors, and how each of these receptors contributes to pore-formation remains unknown. To begin to resolve this, we performed an alanine scanning mutagenesis screen to identify mutations that allow LukAB to maintain cytotoxicity without CD11b. We discovered 30 mutations primarily localized in the stem domains of LukA and LukB that enable LukAB to exhibit full cytotoxicity in the absence of CD11b. Using crosslinking, electron microscopy, and hydroxyl radical protein footprinting, we show these mutations increase the solvent accessibility of the stem domain, priming LukAB for oligomerization. Together, our data support a model in which CD11b binding unlatches the membrane penetrating stem domains of LukAB, and this change in flexibility promotes toxin oligomerization.
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Affiliation(s)
- Juliana K Ilmain
- Department of Microbiology, New York University Grossman School of Medicine, New York, New York, USA
| | - Sofya S Perelman
- Department of Microbiology, New York University Grossman School of Medicine, New York, New York, USA
| | - Maria C Panepinto
- Proteomics Laboratory, Division of Advanced Research Technologies, New York University Grossman School of Medicine, New York, New York, USA
| | - Irnov Irnov
- Department of Microbiology, New York University Grossman School of Medicine, New York, New York, USA
| | - Nicolas Coudray
- Applied Bioinformatics Laboratories, New York University Grossman School of Medicine, New York, New York, USA; Department of Cell Biology, New York University Grossman School of Medicine, New York, New York, USA
| | - Nora Samhadaneh
- Antimicrobial-Resistant Pathogens Program, New York University Langone Health, New York, New York, USA
| | - Alejandro Pironti
- Department of Microbiology, New York University Grossman School of Medicine, New York, New York, USA; Antimicrobial-Resistant Pathogens Program, New York University Langone Health, New York, New York, USA
| | - Beatrix Ueberheide
- Proteomics Laboratory, Division of Advanced Research Technologies, New York University Grossman School of Medicine, New York, New York, USA; Department of Biochemistry and Molecular Pharmacology, New York University Grossman School of Medicine, New York, New York, USA; Department of Neurology, Center for Cognitive Neurology, New York University Grossman School of Medicine, New York, New York, USA
| | - Damian C Ekiert
- Department of Microbiology, New York University Grossman School of Medicine, New York, New York, USA; Department of Cell Biology, New York University Grossman School of Medicine, New York, New York, USA; Antimicrobial-Resistant Pathogens Program, New York University Langone Health, New York, New York, USA
| | - Gira Bhabha
- Department of Cell Biology, New York University Grossman School of Medicine, New York, New York, USA; Antimicrobial-Resistant Pathogens Program, New York University Langone Health, New York, New York, USA
| | - Victor J Torres
- Department of Microbiology, New York University Grossman School of Medicine, New York, New York, USA; Department of Host-Microbe Interactions, St Jude Children's Research Hospital, Memphis, Tennessee, USA.
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5
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Hsieh RC, Liu R, Burgin DJ, Otto M. Understanding mechanisms of virulence in MRSA: implications for antivirulence treatment strategies. Expert Rev Anti Infect Ther 2023; 21:911-928. [PMID: 37501364 DOI: 10.1080/14787210.2023.2242585] [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: 05/15/2023] [Accepted: 07/26/2023] [Indexed: 07/29/2023]
Abstract
INTRODUCTION Methicillin-resistant Staphylococcus aureus (MRSA) is a widespread pathogen, often causing recurrent and deadly infections in the hospital and community. Many S. aureus virulence factors have been suggested as potential targets for antivirulence therapy to decrease the threat of diminishing antibiotic availability. Antivirulence methods hold promise due to their adjunctive and prophylactic potential and decreased risk for selective pressure. AREAS COVERED This review describes the dominant virulence mechanisms exerted by MRSA and antivirulence therapeutics that are currently undergoing testing in clinical or preclinical stages. We also discuss the advantages and downsides of several investigational antivirulence approaches, including the targeting of bacterial transporters, host-directed therapy, and quorum-sensing inhibitors. For this review, a systematic search of literature on PubMed, Google Scholar, and Web of Science for relevant search terms was performed in April and May 2023. EXPERT OPINION Vaccine and antibody strategies have failed in clinical trials and could benefit from more basic science-informed approaches. Antivirulence-targeting approaches need to be set up better to meet the requirements of drug development, rather than only providing limited results to provide 'proof-of-principle' translational value of pathogenesis research. Nevertheless, there is great potential of such strategies and potential particular promise for novel probiotic approaches.
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Affiliation(s)
- Roger C Hsieh
- Pathogen Molecular Genetics Section, Laboratory of Bacteriology, National Institute of Allergy and Infectious Diseases (NIAID), U.S. National Institutes of Health (NIH), Bethesda, Maryland, USA
| | - Ryan Liu
- Pathogen Molecular Genetics Section, Laboratory of Bacteriology, National Institute of Allergy and Infectious Diseases (NIAID), U.S. National Institutes of Health (NIH), Bethesda, Maryland, USA
| | - Dylan J Burgin
- Pathogen Molecular Genetics Section, Laboratory of Bacteriology, National Institute of Allergy and Infectious Diseases (NIAID), U.S. National Institutes of Health (NIH), Bethesda, Maryland, USA
| | - Michael Otto
- Pathogen Molecular Genetics Section, Laboratory of Bacteriology, National Institute of Allergy and Infectious Diseases (NIAID), U.S. National Institutes of Health (NIH), Bethesda, Maryland, USA
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Buckley PT, Chan R, Fernandez J, Luo J, Lacey KA, DuMont AL, O'Malley A, Brezski RJ, Zheng S, Malia T, Whitaker B, Zwolak A, Payne A, Clark D, Sigg M, Lacy ER, Kornilova A, Kwok D, McCarthy S, Wu B, Morrow B, Nemeth-Seay J, Petley T, Wu S, Strohl WR, Lynch AS, Torres VJ. Multivalent human antibody-centyrin fusion protein to prevent and treat Staphylococcus aureus infections. Cell Host Microbe 2023; 31:751-765.e11. [PMID: 37098341 DOI: 10.1016/j.chom.2023.04.004] [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: 04/19/2022] [Revised: 02/12/2023] [Accepted: 04/03/2023] [Indexed: 04/27/2023]
Abstract
Treating and preventing infections by antimicrobial-resistant bacterial pathogens is a worldwide problem. Pathogens such as Staphylococcus aureus produce an array of virulence determinants, making it difficult to identify single targets for the development of vaccines or monoclonal therapies. We described a human-derived anti-S. aureus monoclonal antibody (mAb)-centyrin fusion protein ("mAbtyrin") that simultaneously targets multiple bacterial adhesins, resists proteolysis by bacterial protease GluV8, avoids Fc engagement by S. aureus IgG-binding proteins SpA and Sbi, and neutralizes pore-forming leukocidins via fusion with anti-toxin centyrins, while maintaining Fc- and complement-mediated functions. Compared with the parental mAb, mAbtyrin protected human phagocytes and boosted phagocyte-mediated killing. The mAbtyrin also reduced pathology, reduced bacterial burden, and protected from different types of infections in preclinical animal models. Finally, mAbtyrin synergized with vancomycin, enhancing pathogen clearance in an animal model of bacteremia. Altogether, these data establish the potential of multivalent mAbs for treating and preventing S. aureus diseases.
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Affiliation(s)
- Peter T Buckley
- Janssen Research & Development, 1400 McKean Road, Spring House, PA, USA.
| | - Rita Chan
- Department of Microbiology, New York University Grossman School of Medicine, Alexandria Center for Life Science, 430 East 29th Street, New York, NY 10016, USA
| | - Jeffrey Fernandez
- Janssen Research & Development, 1400 McKean Road, Spring House, PA, USA
| | - Jinquan Luo
- Janssen Research & Development, 1400 McKean Road, Spring House, PA, USA
| | - Keenan A Lacey
- Department of Microbiology, New York University Grossman School of Medicine, Alexandria Center for Life Science, 430 East 29th Street, New York, NY 10016, USA
| | - Ashley L DuMont
- Department of Microbiology, New York University Grossman School of Medicine, Alexandria Center for Life Science, 430 East 29th Street, New York, NY 10016, USA
| | - Aidan O'Malley
- Department of Microbiology, New York University Grossman School of Medicine, Alexandria Center for Life Science, 430 East 29th Street, New York, NY 10016, USA
| | - Randall J Brezski
- Janssen Research & Development, 1400 McKean Road, Spring House, PA, USA
| | - Songmao Zheng
- Janssen Research & Development, 1400 McKean Road, Spring House, PA, USA
| | - Thomas Malia
- Janssen Research & Development, 1400 McKean Road, Spring House, PA, USA
| | - Brian Whitaker
- Janssen Research & Development, 1400 McKean Road, Spring House, PA, USA
| | - Adam Zwolak
- Janssen Research & Development, 1400 McKean Road, Spring House, PA, USA
| | - Angela Payne
- Janssen Research & Development, 1400 McKean Road, Spring House, PA, USA
| | - Desmond Clark
- Janssen Research & Development, 1400 McKean Road, Spring House, PA, USA
| | - Martin Sigg
- Janssen Research & Development, 1400 McKean Road, Spring House, PA, USA
| | - Eilyn R Lacy
- Janssen Research & Development, 1400 McKean Road, Spring House, PA, USA
| | - Anna Kornilova
- Janssen Research & Development, 1400 McKean Road, Spring House, PA, USA
| | - Debra Kwok
- Janssen Research & Development, 1400 McKean Road, Spring House, PA, USA
| | - Steve McCarthy
- Janssen Research & Development, 1400 McKean Road, Spring House, PA, USA
| | - Bingyuan Wu
- Janssen Research & Development, 1400 McKean Road, Spring House, PA, USA
| | - Brian Morrow
- Janssen Research & Development, 1400 McKean Road, Spring House, PA, USA
| | | | - Ted Petley
- Janssen Research & Development, 1400 McKean Road, Spring House, PA, USA
| | - Sam Wu
- Janssen Research & Development, 1400 McKean Road, Spring House, PA, USA
| | - William R Strohl
- Janssen Research & Development, 1400 McKean Road, Spring House, PA, USA
| | | | - Victor J Torres
- Department of Microbiology, New York University Grossman School of Medicine, Alexandria Center for Life Science, 430 East 29th Street, New York, NY 10016, USA; Antimicrobial-Resistant Pathogens Program, New York University Langone Health, Alexandria Center for Life Science, 430 East 29th Street, New York, NY 10016, USA.
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Howden BP, Giulieri SG, Wong Fok Lung T, Baines SL, Sharkey LK, Lee JYH, Hachani A, Monk IR, Stinear TP. Staphylococcus aureus host interactions and adaptation. Nat Rev Microbiol 2023; 21:380-395. [PMID: 36707725 PMCID: PMC9882747 DOI: 10.1038/s41579-023-00852-y] [Citation(s) in RCA: 81] [Impact Index Per Article: 81.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Accepted: 01/04/2023] [Indexed: 01/28/2023]
Abstract
Invasive Staphylococcus aureus infections are common, causing high mortality, compounded by the propensity of the bacterium to develop drug resistance. S. aureus is an excellent case study of the potential for a bacterium to be commensal, colonizing, latent or disease-causing; these states defined by the interplay between S. aureus and host. This interplay is multidimensional and evolving, exemplified by the spread of S. aureus between humans and other animal reservoirs and the lack of success in vaccine development. In this Review, we examine recent advances in understanding the S. aureus-host interactions that lead to infections. We revisit the primary role of neutrophils in controlling infection, summarizing the discovery of new immune evasion molecules and the discovery of new functions ascribed to well-known virulence factors. We explore the intriguing intersection of bacterial and host metabolism, where crosstalk in both directions can influence immune responses and infection outcomes. This Review also assesses the surprising genomic plasticity of S. aureus, its dualism as a multi-mammalian species commensal and opportunistic pathogen and our developing understanding of the roles of other bacteria in shaping S. aureus colonization.
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Affiliation(s)
- Benjamin P. Howden
- grid.1008.90000 0001 2179 088XCentre for Pathogen Genomics, The University of Melbourne, Melbourne, Victoria Australia ,grid.1008.90000 0001 2179 088XDepartment of Microbiology and Immunology, The University of Melbourne, The Peter Doherty Institute for Infection and Immunity, Melbourne, Victoria Australia ,grid.410678.c0000 0000 9374 3516Department of Infectious Diseases, Austin Health, Heidelberg, Victoria Australia ,grid.416153.40000 0004 0624 1200Microbiology Department, Royal Melbourne Hospital, Melbourne, Victoria Australia
| | - Stefano G. Giulieri
- grid.1008.90000 0001 2179 088XDepartment of Microbiology and Immunology, The University of Melbourne, The Peter Doherty Institute for Infection and Immunity, Melbourne, Victoria Australia ,grid.416153.40000 0004 0624 1200Victorian Infectious Diseases Service, Royal Melbourne Hospital, The Peter Doherty Institute for Infection and Immunity, Melbourne, Victoria Australia
| | - Tania Wong Fok Lung
- grid.21729.3f0000000419368729Department of Paediatrics, Columbia University, New York, NY USA
| | - Sarah L. Baines
- grid.1008.90000 0001 2179 088XDepartment of Microbiology and Immunology, The University of Melbourne, The Peter Doherty Institute for Infection and Immunity, Melbourne, Victoria Australia
| | - Liam K. Sharkey
- grid.1008.90000 0001 2179 088XDepartment of Microbiology and Immunology, The University of Melbourne, The Peter Doherty Institute for Infection and Immunity, Melbourne, Victoria Australia
| | - Jean Y. H. Lee
- grid.1008.90000 0001 2179 088XDepartment of Microbiology and Immunology, The University of Melbourne, The Peter Doherty Institute for Infection and Immunity, Melbourne, Victoria Australia ,grid.419789.a0000 0000 9295 3933Department of Infectious Diseases, Monash Health, Clayton, Victoria Australia
| | - Abderrahman Hachani
- grid.1008.90000 0001 2179 088XDepartment of Microbiology and Immunology, The University of Melbourne, The Peter Doherty Institute for Infection and Immunity, Melbourne, Victoria Australia
| | - Ian R. Monk
- grid.1008.90000 0001 2179 088XDepartment of Microbiology and Immunology, The University of Melbourne, The Peter Doherty Institute for Infection and Immunity, Melbourne, Victoria Australia
| | - Timothy P. Stinear
- grid.1008.90000 0001 2179 088XCentre for Pathogen Genomics, The University of Melbourne, Melbourne, Victoria Australia ,grid.1008.90000 0001 2179 088XDepartment of Microbiology and Immunology, The University of Melbourne, The Peter Doherty Institute for Infection and Immunity, Melbourne, Victoria Australia
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8
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Langouët-Astrié C, Oshima K, McMurtry SA, Yang Y, Kwiecinski JM, LaRivière WB, Kavanaugh JS, Zakharevich I, Hansen KC, Shi D, Zhang F, Boguslawski KM, Perelman SS, Su G, Torres VJ, Liu J, Horswill AR, Schmidt EP. The influenza-injured lung microenvironment promotes MRSA virulence, contributing to severe secondary bacterial pneumonia. Cell Rep 2022; 41:111721. [PMID: 36450248 PMCID: PMC10082619 DOI: 10.1016/j.celrep.2022.111721] [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: 04/19/2022] [Revised: 10/12/2022] [Accepted: 11/03/2022] [Indexed: 12/03/2022] Open
Abstract
Influenza infection is substantially worsened by the onset of secondary pneumonia caused by bacteria, such as methicillin-resistant Staphylococcus aureus (MRSA). The bidirectional interaction between the influenza-injured lung microenvironment and MRSA is poorly understood. By conditioning MRSA ex vivo in bronchoalveolar lavage fluid collected from mice at various time points of influenza infection, we found that the influenza-injured lung microenvironment dynamically induces MRSA to increase cytotoxin expression while decreasing metabolic pathways. LukAB, a SaeRS two-component system-dependent cytotoxin, is particularly important to the severity of post-influenza MRSA pneumonia. LukAB's activity is likely shaped by the post-influenza lung microenvironment, as LukAB binds to (and is activated by) heparan sulfate (HS) oligosaccharide sequences shed from the epithelial glycocalyx after influenza. Our findings indicate that post-influenza MRSA pneumonia is shaped by bidirectional host-pathogen interactions: host injury triggers changes in bacterial expression of toxins, the activity of which may be shaped by host-derived HS fragments.
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Affiliation(s)
| | - Kaori Oshima
- Division of Pulmonary Sciences and Critical Care, University of Colorado Denver, Aurora, CO 80045, USA
| | - Sarah A McMurtry
- Division of Pulmonary Sciences and Critical Care, University of Colorado Denver, Aurora, CO 80045, USA
| | - Yimu Yang
- Division of Pulmonary Sciences and Critical Care, University of Colorado Denver, Aurora, CO 80045, USA
| | - Jakub M Kwiecinski
- Department of Immunology & Microbiology, University of Colorado School of Medicine, Aurora, CO 80045, USA; Department of Microbiology, Faculty of Biochemistry, Biophysics and Biotechnology, Jagiellonian University, Krakow 30387, Poland
| | - Wells B LaRivière
- Division of Pulmonary Sciences and Critical Care, University of Colorado Denver, Aurora, CO 80045, USA; Medical Scientist Training Program, University of Colorado School of Medicine, Aurora, CO 80045, USA
| | - Jeffrey S Kavanaugh
- Department of Immunology & Microbiology, University of Colorado School of Medicine, Aurora, CO 80045, USA
| | - Igor Zakharevich
- Department of Biochemistry and Molecular Genetics, University of Colorado, Aurora, CO 80045, USA
| | - Kirk C Hansen
- Department of Biochemistry and Molecular Genetics, University of Colorado, Aurora, CO 80045, USA
| | - Deling Shi
- Department of Chemistry, Rensselaer Polytechnic Institute, Troy, NY 12180, USA
| | - Fuming Zhang
- Department of Chemistry, Rensselaer Polytechnic Institute, Troy, NY 12180, USA
| | - Kristina M Boguslawski
- Department of Microbiology, New York University School of Medicine, New York, NY 10016, USA
| | - Sofya S Perelman
- Department of Microbiology, New York University School of Medicine, New York, NY 10016, USA
| | - Gouwei Su
- University of North Carolina Eshelman School of Pharmacy, Chapel Hill, NC 27599, USA
| | - Victor J Torres
- Department of Microbiology, New York University School of Medicine, New York, NY 10016, USA
| | - Jian Liu
- University of North Carolina Eshelman School of Pharmacy, Chapel Hill, NC 27599, USA
| | - Alexander R Horswill
- Department of Immunology & Microbiology, University of Colorado School of Medicine, Aurora, CO 80045, USA
| | - Eric P Schmidt
- Division of Pulmonary Sciences and Critical Care, University of Colorado Denver, Aurora, CO 80045, USA; Department of Medicine, Massachusetts General Hospital, Boston, MA 02115, USA
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9
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Staphylococcus aureus induces a muted host response in human blood that blunts the recruitment of neutrophils. Proc Natl Acad Sci U S A 2022; 119:e2123017119. [PMID: 35881802 PMCID: PMC9351360 DOI: 10.1073/pnas.2123017119] [Citation(s) in RCA: 11] [Impact Index Per Article: 5.5] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/18/2022] Open
Abstract
Staphylococcus aureus is an opportunistic pathogen and chief among bloodstream-infecting bacteria. S. aureus produces an array of human-specific virulence factors that may contribute to immune suppression. Here, we defined the response of primary human phagocytes following infection with S. aureus using RNA-sequencing (RNA-Seq). We found that the overall transcriptional response to S. aureus was weak both in the number of genes and in the magnitude of response. Using an ex vivo bacteremia model with fresh human blood, we uncovered that infection with S. aureus resulted in the down-regulation of genes related to innate immune response and cytokine and chemokine signaling. This muted transcriptional response was conserved across diverse S. aureus clones but absent in blood exposed to heat-killed S. aureus or blood infected with the less virulent staphylococcal species Staphylococcus epidermidis. Notably, this signature was also present in patients with S. aureus bacteremia. We identified the master regulator S. aureus exoprotein expression (SaeRS) and the SaeRS-regulated pore-forming toxins as key mediators of the transcriptional suppression. The S. aureus-mediated suppression of chemokine and cytokine transcription was reflected by circulating protein levels in the plasma. Wild-type S. aureus elicited a soluble milieu that was restrictive in the recruitment of human neutrophils compared with strains lacking saeRS. Thus, S. aureus blunts the inflammatory response resulting in impaired neutrophil recruitment, which could promote the survival of the pathogen during invasive infection.
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10
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Akoua-Koffi C, Kacou N’Douba A, Djaman JA, Herrmann M, Schaumburg F, Niemann S. Staphylococcus schweitzeri—An Emerging One Health Pathogen? Microorganisms 2022; 10:microorganisms10040770. [PMID: 35456820 PMCID: PMC9026344 DOI: 10.3390/microorganisms10040770] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/17/2022] [Revised: 03/28/2022] [Accepted: 03/31/2022] [Indexed: 11/22/2022] Open
Abstract
The Staphylococcus aureus-related complex is formed by the Staphylococcus aureus, Staphylococcus schweitzeri, Staphylococcus argenteus, Staphylococcus roterodami and Staphylococcus singaporensis. Within this complex, S. schweitzeri is the only species mainly found in African wildlife, but it is rarely detected as a colonizer in humans or as a contaminant of fomites. The few detections in humans are most likely spillover events after contact with wildlife. However, since S. schweitzeri can be misidentified as S. aureus using culture-based routine techniques, it is likely that S. schweitzeri is under-reported in humans. The low number of isolates in humans, though, is consistent with the fact that the pathogen has typical animal adaptation characteristics (e.g., growth kinetics, lack of immune evasion cluster and antimicrobial resistance); however, evidence from selected in vitro assays (e.g., host cell invasion, cell activation, cytotoxicity) indicate that S. schweitzeri might be as virulent as S. aureus. In this case, contact with animals colonized with S. schweitzeri could constitute a risk for zoonotic infections. With respect to antimicrobial resistance, all described isolates were found to be susceptible to all antibiotics tested, and so far no data on the development of spontaneous resistance or the acquisition of resistance genes such the mecA/mecC cassette are available. In summary, general knowledge about this pathogen, specifically on the potential threat it may incur to human and animal health, is still very poor. In this review article, we compile the present state of scientific research, and identify the knowledge gaps that need to be filled in order to reliably assess S. schweitzeri as an organism with global One Health implications.
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Affiliation(s)
- Chantal Akoua-Koffi
- Centre Hospitalier Universitaire de Bouaké, Bouaké P.O. Box BP 1174, Côte d’Ivoire;
- Department of Biology, Université Alassane Ouattara de Bouaké, Bouaké P.O. Box BP V18, Côte d’Ivoire
| | - Adèle Kacou N’Douba
- Training and Research Unit of Medical Sciences, Félix Houphouët-Boigny University, Abidjan P.O. Box BP 44, Côte d’Ivoire;
- Centre Hospitalier Universitaire Angré, Abidjan P.O. Box BP 1530, Côte d’Ivoire
| | - Joseph Allico Djaman
- Training and Research Unit of Biosciences, Félix Houphouët Boigny University, Abidjan P.O. Box BP V 34, Côte d’Ivoire;
| | - Mathias Herrmann
- Institute of Medical Microbiology, University Hospital Münster, 48149 Münster, Germany; (M.H.); (F.S.)
| | - Frieder Schaumburg
- Institute of Medical Microbiology, University Hospital Münster, 48149 Münster, Germany; (M.H.); (F.S.)
| | - Silke Niemann
- Institute of Medical Microbiology, University Hospital Münster, 48149 Münster, Germany; (M.H.); (F.S.)
- Correspondence: ; Tel.: +49-251-835-5369
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11
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Xiong X, Tian S, Yang P, Lebreton F, Bao H, Sheng K, Yin L, Chen P, Zhang J, Qi W, Ruan J, Wu H, Chen H, Breault DT, Wu H, Earl AM, Gilmore MS, Abraham J, Dong M. Emerging enterococcus pore-forming toxins with MHC/HLA-I as receptors. Cell 2022; 185:1157-1171.e22. [PMID: 35259335 PMCID: PMC8978092 DOI: 10.1016/j.cell.2022.02.002] [Citation(s) in RCA: 17] [Impact Index Per Article: 8.5] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/02/2021] [Revised: 12/15/2021] [Accepted: 02/01/2022] [Indexed: 01/12/2023]
Abstract
Enterococci are a part of human microbiota and a leading cause of multidrug resistant infections. Here, we identify a family of Enterococcus pore-forming toxins (Epxs) in E. faecalis, E. faecium, and E. hirae strains isolated across the globe. Structural studies reveal that Epxs form a branch of β-barrel pore-forming toxins with a β-barrel protrusion (designated the top domain) sitting atop the cap domain. Through a genome-wide CRISPR-Cas9 screen, we identify human leukocyte antigen class I (HLA-I) complex as a receptor for two members (Epx2 and Epx3), which preferentially recognize human HLA-I and homologous MHC-I of equine, bovine, and porcine, but not murine, origin. Interferon exposure, which stimulates MHC-I expression, sensitizes human cells and intestinal organoids to Epx2 and Epx3 toxicity. Co-culture with Epx2-harboring E. faecium damages human peripheral blood mononuclear cells and intestinal organoids, and this toxicity is neutralized by an Epx2 antibody, demonstrating the toxin-mediated virulence of Epx-carrying Enterococcus.
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Affiliation(s)
- Xiaozhe Xiong
- Department of Urology, Boston Children's Hospital, Department of Surgery, Harvard Medical School, Boston, MA 02115, USA; Department of Microbiology, Harvard Medical School, Boston, MA 02115, USA
| | - Songhai Tian
- Department of Urology, Boston Children's Hospital, Department of Surgery, Harvard Medical School, Boston, MA 02115, USA; Department of Microbiology, Harvard Medical School, Boston, MA 02115, USA
| | - Pan Yang
- Department of Microbiology, Harvard Medical School, Boston, MA 02115, USA
| | - Francois Lebreton
- Department of Microbiology, Harvard Medical School, Boston, MA 02115, USA; Department of Ophthalmology, Harvard Medical School, Massachusetts Eye and Ear Infirmary, Boston, MA 02114, USA; Broad Institute of MIT and Harvard, Cambridge, MA 02142, USA; Multidrug-Resistant Organism Repository and Surveillance Network (MRSN), Walter Reed Army Institute of Research, Silver Spring, MD 20910, USA
| | - Huan Bao
- Department of Molecular Medicine, The Scripps Research Institute, Jupiter, FL 33458, USA
| | - Kuanwei Sheng
- Wyss Institute for Biologically Inspired Engineering, Harvard University, Boston, MA 02115
| | - Linxiang Yin
- Department of Urology, Boston Children's Hospital, Department of Surgery, Harvard Medical School, Boston, MA 02115, USA; Department of Microbiology, Harvard Medical School, Boston, MA 02115, USA
| | - Pengsheng Chen
- Department of Urology, Boston Children's Hospital, Department of Surgery, Harvard Medical School, Boston, MA 02115, USA; Department of Microbiology, Harvard Medical School, Boston, MA 02115, USA
| | - Jie Zhang
- Department of Urology, Boston Children's Hospital, Department of Surgery, Harvard Medical School, Boston, MA 02115, USA
| | - Wanshu Qi
- Division of Endocrinology, Boston Children's Hospital, and Department of Pediatrics, Harvard Medical School, Boston, MA 02115, USA
| | - Jianbin Ruan
- Program in Cellular and Molecular Medicine, Boston Children's Hospital, and Department of Biological Chemistry and Molecular Pharmacology, Harvard Medical School, Boston, MA 02115, USA; Department of Immunology, University of Connecticut Health School of Medicine, Farmington, CT 06030, USA
| | - Hao Wu
- Vascular Biology Program, Department of Surgery, Boston Children's Hospital and Harvard Medical School, Boston, MA 02115, USA
| | - Hong Chen
- Vascular Biology Program, Department of Surgery, Boston Children's Hospital and Harvard Medical School, Boston, MA 02115, USA
| | - David T Breault
- Division of Endocrinology, Boston Children's Hospital, and Department of Pediatrics, Harvard Medical School, Boston, MA 02115, USA; Harvard Stem Cell Institute, Cambridge, MA 02138, USA
| | - Hao Wu
- Program in Cellular and Molecular Medicine, Boston Children's Hospital, and Department of Biological Chemistry and Molecular Pharmacology, Harvard Medical School, Boston, MA 02115, USA
| | - Ashlee M Earl
- Broad Institute of MIT and Harvard, Cambridge, MA 02142, USA
| | - Michael S Gilmore
- Department of Microbiology, Harvard Medical School, Boston, MA 02115, USA; Department of Ophthalmology, Harvard Medical School, Massachusetts Eye and Ear Infirmary, Boston, MA 02114, USA; Broad Institute of MIT and Harvard, Cambridge, MA 02142, USA.
| | - Jonathan Abraham
- Department of Microbiology, Harvard Medical School, Boston, MA 02115, USA; Broad Institute of MIT and Harvard, Cambridge, MA 02142, USA; Division of Infectious Diseases, Department of Medicine, Brigham and Women's Hospital, Boston, MA 02115, USA.
| | - Min Dong
- Department of Urology, Boston Children's Hospital, Department of Surgery, Harvard Medical School, Boston, MA 02115, USA; Department of Microbiology, Harvard Medical School, Boston, MA 02115, USA.
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12
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The Major Autolysin Atl Regulates the Virulence of Staphylococcus aureus by Controlling the Sorting of LukAB. Infect Immun 2022; 90:e0005622. [PMID: 35258336 PMCID: PMC9022505 DOI: 10.1128/iai.00056-22] [Citation(s) in RCA: 6] [Impact Index Per Article: 3.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/14/2023] Open
Abstract
Infections caused by the Gram-positive bacterium Staphylococcus aureus remain a significant health threat globally. The production of bicomponent pore-forming leukocidins plays an important role in S. aureus pathogenesis. Transcriptionally, these toxins are primarily regulated by the Sae and Agr regulatory systems. However, the posttranslational regulation of these toxins is largely unexplored. In particular, one of the leukocidins, LukAB, has been shown to be both secreted into the extracellular milieu and associated with the bacterial cell envelope. Here, we report that a major cell wall hydrolase, autolysin (Atl), controls the sorting of LukAB from the cell envelope to the extracellular milieu, an effect independent of transcriptional regulation. By influencing the sorting of LukAB, Atl modulates S. aureus cytotoxicity toward primary human neutrophils. Mechanistically, we found that the reduction in peptidoglycan cleavage and increased LukAB secretion in the atl mutant can be reversed through the supplementation of exogenous mutanolysin. Altogether, our study revealed that the cell wall hydrolase activity of Atl and the cleavage of peptidoglycan play an important role in controlling the sorting of S. aureus toxins during secretion.
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13
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Ulhuq FR, Mariano G. Bacterial pore-forming toxins. MICROBIOLOGY (READING, ENGLAND) 2022; 168:001154. [PMID: 35333704 PMCID: PMC9558359 DOI: 10.1099/mic.0.001154] [Citation(s) in RCA: 13] [Impact Index Per Article: 6.5] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Subscribe] [Scholar Register] [Received: 11/25/2021] [Accepted: 02/03/2022] [Indexed: 12/11/2022]
Abstract
Pore-forming toxins (PFTs) are widely distributed in both Gram-negative and Gram-positive bacteria. PFTs can act as virulence factors that bacteria utilise in dissemination and host colonisation or, alternatively, they can be employed to compete with rival microbes in polymicrobial niches. PFTs transition from a soluble form to become membrane-embedded by undergoing large conformational changes. Once inserted, they perforate the membrane, causing uncontrolled efflux of ions and/or nutrients and dissipating the protonmotive force (PMF). In some instances, target cells intoxicated by PFTs display additional effects as part of the cellular response to pore formation. Significant progress has been made in the mechanistic description of pore formation for the different PFTs families, but in several cases a complete understanding of pore structure remains lacking. PFTs have evolved recognition mechanisms to bind specific receptors that define their host tropism, although this can be remarkably diverse even within the same family. Here we summarise the salient features of PFTs and highlight where additional research is necessary to fully understand the mechanism of pore formation by members of this diverse group of protein toxins.
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Affiliation(s)
- Fatima R. Ulhuq
- Microbes in Health and Disease Theme, Newcastle University Biosciences Institute, Newcastle University, Newcastle upon Tyne, UK
| | - Giuseppina Mariano
- Microbes in Health and Disease Theme, Newcastle University Biosciences Institute, Newcastle University, Newcastle upon Tyne, UK
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14
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Shahi I, Llaneras CN, Perelman SS, Torres VJ, Ratner AJ. Genome-Wide CRISPR-Cas9 Screen Does Not Identify Host Factors Modulating Streptococcus agalactiae β-Hemolysin/Cytolysin-Induced Cell Death. Microbiol Spectr 2022; 10:e0218621. [PMID: 35196804 PMCID: PMC8865549 DOI: 10.1128/spectrum.02186-21] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/08/2021] [Accepted: 01/07/2022] [Indexed: 11/20/2022] Open
Abstract
Pore-forming toxins (PFTs) are commonly produced by pathogenic bacteria, and understanding them is key to the development of virulence-targeted therapies. Streptococcus agalactiae, or group B Streptococcus (GBS), produces several factors that enhance its pathogenicity, including the PFT β-hemolysin/cytolysin (βhc). Little is understood about the cellular factors involved in βhc pore formation. We conducted a whole-genome CRISPR-Cas9 forward genetic screen to identify host genes that might contribute to βhc pore formation and cell death. While the screen identified the established receptor, CD59, in control experiments using the toxin intermedilysin (ILY), no clear candidate genes were identified that were required for βhc-mediated lethality. Of the top targets from the screen, two genes involved in membrane remodeling and repair represented candidates that might modulate the kinetics of βhc-induced cell death. Upon attempted validation of the results using monoclonal cell lines with targeted disruption of these genes, no effect on βhc-mediated cell lysis was observed. The CRISPR-Cas9 screen results are consistent with the hypothesis that βhc does not require a single nonessential host factor to mediate target cell death. IMPORTANCE CRISPR-Cas9 forward genetic screens have been used to identify host cell targets required by bacterial toxins. They have been used successfully to both verify known targets and elucidate novel host factors required by toxins. Here, we show that this approach fails to identify host factors required for cell death due to βhc, a toxin required for GBS virulence. These data suggest that βhc may not require a host cell receptor for toxin function or may require a host receptor that is an essential gene and would not be identified using this screening strategy.
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Affiliation(s)
- Ifrah Shahi
- Department of Microbiology, New York University Grossman School of Medicine, New York, New York, USA
| | - Cristina N. Llaneras
- Department of Microbiology, New York University Grossman School of Medicine, New York, New York, USA
| | - Sofya S. Perelman
- Department of Microbiology, New York University Grossman School of Medicine, New York, New York, USA
| | - Victor J. Torres
- Department of Microbiology, New York University Grossman School of Medicine, New York, New York, USA
- Antimicrobial-Resistant Pathogens Program, New York University Grossman School of Medicine, New York, New York, USA
| | - Adam J. Ratner
- Department of Microbiology, New York University Grossman School of Medicine, New York, New York, USA
- Antimicrobial-Resistant Pathogens Program, New York University Grossman School of Medicine, New York, New York, USA
- Department of Pediatrics, New York University Grossman School of Medicine, New York, New York, USA
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15
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von Köckritz-Blickwede M, Winstel V. Molecular Prerequisites for Neutrophil Extracellular Trap Formation and Evasion Mechanisms of Staphylococcus aureus. Front Immunol 2022; 13:836278. [PMID: 35237275 PMCID: PMC8884242 DOI: 10.3389/fimmu.2022.836278] [Citation(s) in RCA: 19] [Impact Index Per Article: 9.5] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/15/2021] [Accepted: 01/19/2022] [Indexed: 12/15/2022] Open
Abstract
NETosis is a multi-facetted cellular process that promotes the formation of neutrophil extracellular traps (NETs). NETs as web-like structures consist of DNA fibers armed with granular proteins, histones, and microbicidal peptides, thereby exhibiting pathogen-immobilizing and antimicrobial attributes that maximize innate immune defenses against invading microbes. However, clinically relevant pathogens often tolerate entrapment and even take advantage of the remnants of NETs to cause persistent infections in mammalian hosts. Here, we briefly summarize how Staphylococcus aureus, a high-priority pathogen and causative agent of fatal diseases in humans as well as animals, catalyzes and concurrently exploits NETs during pathogenesis and recurrent infections. Specifically, we focus on toxigenic and immunomodulatory effector molecules produced by staphylococci that prime NET formation, and further highlight the molecular and underlying principles of suicidal NETosis compared to vital NET-formation by viable neutrophils in response to these stimuli. We also discuss the inflammatory potential of NET-controlled microenvironments, as excessive expulsion of NETs from activated neutrophils provokes local tissue injury and may therefore amplify staphylococcal disease severity in hospitalized or chronically ill patients. Combined with an overview of adaptation and counteracting strategies evolved by S. aureus to impede NET-mediated killing, these insights may stimulate biomedical research activities to uncover novel aspects of NET biology at the host-microbe interface.
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Affiliation(s)
- Maren von Köckritz-Blickwede
- Department of Biochemistry, University of Veterinary Medicine Hannover, Hannover, Germany
- Research Center for Emerging Infections and Zoonoses (RIZ), University of Veterinary Medicine Hannover, Hannover, Germany
| | - Volker Winstel
- Research Group Pathogenesis of Bacterial Infections, TWINCORE, Centre for Experimental and Clinical Infection Research, a joint venture between the Hannover Medical School and the Helmholtz Centre for Infection Research, Hannover, Germany
- Institute of Medical Microbiology and Hospital Epidemiology, Hannover Medical School, Hannover, Germany
- *Correspondence: Volker Winstel,
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