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Seabaugh JA, Anderson DM. Pathogenicity and virulence of Yersinia. Virulence 2024; 15:2316439. [PMID: 38389313 PMCID: PMC10896167 DOI: 10.1080/21505594.2024.2316439] [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: 10/05/2023] [Accepted: 02/04/2024] [Indexed: 02/24/2024] Open
Abstract
The genus Yersinia includes human, animal, insect, and plant pathogens as well as many symbionts and harmless bacteria. Within this genus are Yersinia enterocolitica and the Yersinia pseudotuberculosis complex, with four human pathogenic species that are highly related at the genomic level including the causative agent of plague, Yersinia pestis. Extensive laboratory, field work, and clinical research have been conducted to understand the underlying pathogenesis and zoonotic transmission of these pathogens. There are presently more than 500 whole genome sequences from which an evolutionary footprint can be developed that details shared and unique virulence properties. Whereas the virulence of Y. pestis now seems in apparent homoeostasis within its flea transmission cycle, substantial evolutionary changes that affect transmission and disease severity continue to ndergo apparent selective pressure within the other Yersiniae that cause intestinal diseases. In this review, we will summarize the present understanding of the virulence and pathogenesis of Yersinia, highlighting shared mechanisms of virulence and the differences that determine the infection niche and disease severity.
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Affiliation(s)
- Jarett A. Seabaugh
- Department of Veterinary Pathobiology, University of Missouri, Columbia, USA
| | - Deborah M. Anderson
- Department of Veterinary Pathobiology, University of Missouri, Columbia, USA
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Wang X, Hao X, Yang Y, Jia S, Chen Y, Yang W, Luo Y, Xie Z, Gu Y, Wu Y, Zhang F, Li M, Wang Y, Shen X, Xu L. A phosphodiesterase CpdB in Yersinia pseudotuberculosis degrades CDNs to inhibit innate immune response. Vet Microbiol 2024; 297:110194. [PMID: 39084162 DOI: 10.1016/j.vetmic.2024.110194] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/09/2023] [Revised: 07/08/2024] [Accepted: 07/21/2024] [Indexed: 08/02/2024]
Abstract
Yersinia pseudotuberculosis (Yptb) is a pathogenic gram-negative bacterium that can colonize the intestines of different animals. Its infection leads to the activation of the host's innate immunity. Both host and bacterial-derived cyclic dinucleotides (CDNs) could activate the innate immune response of host cells. In bacteria, CDNs like c-di-AMP, c-di-GMP, or 3'3'-cGAMP can be hydrolyzed by different hydrolases. Recent studies showed that the degradation of those second messengers helps the pathogen evade immune detection. In this study, we identified a hydrolase, YPK_3776, namely CpdB in Yptb. CpdB is predicted to bind bacterial-derived c-di-AMP, c-di-GMP, 3'3'-cGAMP and host-derived 2'3'-cGAMP. Surprisingly, by using high-performance liquid chromatography (HPLC), we found that CpdB could only degrade bacterial-derived CDNs but not host-derived 2'3'-cGAMP. In addition, CpdB has 2'3'-cNMP activity. Consistently, the Yptb mutant lacking the cpdB gene exhibited a higher level of intracellular c-di-GMP. Furthermore, the ∆cpdB mutant elicited stronger innate immune responses during Yptb infection in macrophages, suggesting CpdB enables Yptb to evade host immune surveillance. Furthermore, CpdB inhibited the Yptb-induced innate immune response in a STING-dependent manner. Finally, we showed the ∆cpdB infection in mice model exhibited in lower bacterial burden, as compared to wild-type strain infection, indicating CpdB is important for bacterial survival in the host. Together, we identified a cyclic dinucleotide hydrolase CpdB in Yptb that could degrade bacterial-derived CDNs which help the pathogen to evade immune detection via the STING pathway.
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Affiliation(s)
- Xiao Wang
- State Key Laboratory for Crop Stress Resistance and High-Efficiency Production, Shaanxi Key Laboratory of Agricultural and Environmental Microbiology, College of Life Sciences, Northwest A&F University, Yangling, Shaanxi 712100, China
| | - Xinwei Hao
- State Key Laboratory for Crop Stress Resistance and High-Efficiency Production, Shaanxi Key Laboratory of Agricultural and Environmental Microbiology, College of Life Sciences, Northwest A&F University, Yangling, Shaanxi 712100, China
| | - Yuqing Yang
- State Key Laboratory for Crop Stress Resistance and High-Efficiency Production, Shaanxi Key Laboratory of Agricultural and Environmental Microbiology, College of Life Sciences, Northwest A&F University, Yangling, Shaanxi 712100, China
| | - Siyu Jia
- State Key Laboratory for Crop Stress Resistance and High-Efficiency Production, Shaanxi Key Laboratory of Agricultural and Environmental Microbiology, College of Life Sciences, Northwest A&F University, Yangling, Shaanxi 712100, China
| | - Yating Chen
- State Key Laboratory for Crop Stress Resistance and High-Efficiency Production, Shaanxi Key Laboratory of Agricultural and Environmental Microbiology, College of Life Sciences, Northwest A&F University, Yangling, Shaanxi 712100, China
| | - Wenguang Yang
- State Key Laboratory for Crop Stress Resistance and High-Efficiency Production, Shaanxi Key Laboratory of Agricultural and Environmental Microbiology, College of Life Sciences, Northwest A&F University, Yangling, Shaanxi 712100, China
| | - Yi Luo
- State Key Laboratory for Crop Stress Resistance and High-Efficiency Production, Shaanxi Key Laboratory of Agricultural and Environmental Microbiology, College of Life Sciences, Northwest A&F University, Yangling, Shaanxi 712100, China
| | - Zhen Xie
- State Key Laboratory for Crop Stress Resistance and High-Efficiency Production, Shaanxi Key Laboratory of Agricultural and Environmental Microbiology, College of Life Sciences, Northwest A&F University, Yangling, Shaanxi 712100, China
| | - Yanchao Gu
- State Key Laboratory for Crop Stress Resistance and High-Efficiency Production, Shaanxi Key Laboratory of Agricultural and Environmental Microbiology, College of Life Sciences, Northwest A&F University, Yangling, Shaanxi 712100, China
| | - Yuxuan Wu
- State Key Laboratory for Crop Stress Resistance and High-Efficiency Production, Shaanxi Key Laboratory of Agricultural and Environmental Microbiology, College of Life Sciences, Northwest A&F University, Yangling, Shaanxi 712100, China
| | - Fuhua Zhang
- State Key Laboratory for Crop Stress Resistance and High-Efficiency Production, Shaanxi Key Laboratory of Agricultural and Environmental Microbiology, College of Life Sciences, Northwest A&F University, Yangling, Shaanxi 712100, China
| | - Mengyuan Li
- State Key Laboratory for Crop Stress Resistance and High-Efficiency Production, Shaanxi Key Laboratory of Agricultural and Environmental Microbiology, College of Life Sciences, Northwest A&F University, Yangling, Shaanxi 712100, China
| | - Yao Wang
- State Key Laboratory for Crop Stress Resistance and High-Efficiency Production, Shaanxi Key Laboratory of Agricultural and Environmental Microbiology, College of Life Sciences, Northwest A&F University, Yangling, Shaanxi 712100, China.
| | - Xihui Shen
- State Key Laboratory for Crop Stress Resistance and High-Efficiency Production, Shaanxi Key Laboratory of Agricultural and Environmental Microbiology, College of Life Sciences, Northwest A&F University, Yangling, Shaanxi 712100, China.
| | - Lei Xu
- State Key Laboratory for Crop Stress Resistance and High-Efficiency Production, Shaanxi Key Laboratory of Agricultural and Environmental Microbiology, College of Life Sciences, Northwest A&F University, Yangling, Shaanxi 712100, China.
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Resko ZJ, Suhi RF, Thota AV, Kroken AR. Evidence for intracellular Pseudomonas aeruginosa. J Bacteriol 2024; 206:e0010924. [PMID: 38597609 PMCID: PMC11112991 DOI: 10.1128/jb.00109-24] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 04/11/2024] Open
Abstract
Pseudomonas aeruginosa is a significant cause of global morbidity and mortality. Although it is often regarded as an extracellular pathogen toward human cells, numerous investigations report its ability to survive and replicate within host cells, and additional studies demonstrate specific mechanisms enabling it to adopt an intracellular lifestyle. This ability of P. aeruginosa remains less well-investigated than that of other intracellular bacteria, although it is currently gaining attention. If intracellular bacteria are not killed after entering host cells, they may instead receive protection from immune recognition and experience reduced exposure to antibiotic therapy, among additional potential advantages shared with other facultative intracellular pathogens. For this review, we compiled studies that observe intracellular P. aeruginosa across strains, cell types, and experimental systems in vitro, as well as contextualize these findings with the few studies that report similar observations in vivo. We also seek to address key findings that drove the perception that P. aeruginosa remains extracellular in order to reconcile what is currently understood about intracellular pathogenesis and highlight open questions regarding its contribution to disease.
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Affiliation(s)
- Zachary J. Resko
- Department of Microbiology and Immunology, Loyola University Chicago, Maywood, Illinois, USA
| | - Rachel F. Suhi
- Department of Microbiology and Immunology, Loyola University Chicago, Maywood, Illinois, USA
| | - Adam V. Thota
- Department of Microbiology and Immunology, Loyola University Chicago, Maywood, Illinois, USA
| | - Abby R. Kroken
- Department of Microbiology and Immunology, Loyola University Chicago, Maywood, Illinois, USA
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Jastrab JB, Kagan JC. Strategies of bacterial detection by inflammasomes. Cell Chem Biol 2024; 31:835-850. [PMID: 38636521 PMCID: PMC11103797 DOI: 10.1016/j.chembiol.2024.03.009] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/22/2023] [Revised: 03/09/2024] [Accepted: 03/26/2024] [Indexed: 04/20/2024]
Abstract
Mammalian innate immunity is regulated by pattern-recognition receptors (PRRs) and guard proteins, which use distinct strategies to detect infections. PRRs detect bacterial molecules directly, whereas guards detect host cell manipulations by microbial virulence factors. Despite sensing infection through different mechanisms, both classes of innate immune sensors can activate the inflammasome, an immune complex that can mediate cell death and inflammation. Inflammasome-mediated immune responses are crucial for host defense against many bacterial pathogens and prevent invasion by non-pathogenic organisms. In this review, we discuss the mechanisms by which inflammasomes are stimulated by PRRs and guards during bacterial infection, and the strategies used by virulent bacteria to evade inflammasome-mediated immunity.
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Affiliation(s)
- Jordan B Jastrab
- Division of Gastroenterology, Boston Children's Hospital and Harvard Medical School, Boston, MA 02115, USA; Division of Infectious Diseases, Brigham and Women's Hospital, Boston, MA 02115, USA
| | - Jonathan C Kagan
- Division of Gastroenterology, Boston Children's Hospital and Harvard Medical School, Boston, MA 02115, USA.
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Matsuda R, Sorobetea D, Zhang J, Peterson ST, Grayczyk JP, Yost W, Apenes N, Kovalik ME, Herrmann B, O’Neill RJ, Bohrer AC, Lanza M, Assenmacher CA, Mayer-Barber KD, Shin S, Brodsky IE. A TNF-IL-1 circuit controls Yersinia within intestinal pyogranulomas. J Exp Med 2024; 221:e20230679. [PMID: 38363547 PMCID: PMC10873131 DOI: 10.1084/jem.20230679] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/20/2023] [Revised: 11/22/2023] [Accepted: 01/19/2024] [Indexed: 02/17/2024] Open
Abstract
Tumor necrosis factor (TNF) is a pleiotropic inflammatory cytokine that mediates antimicrobial defense and granuloma formation in response to infection by numerous pathogens. We previously reported that Yersinia pseudotuberculosis colonizes the intestinal mucosa and induces the recruitment of neutrophils and inflammatory monocytes into organized immune structures termed pyogranulomas (PG) that control Yersinia infection. Inflammatory monocytes are essential for the control and clearance of Yersinia within intestinal PG, but how monocytes mediate Yersinia restriction is poorly understood. Here, we demonstrate that TNF signaling in monocytes is required for bacterial containment following enteric Yersinia infection. We further show that monocyte-intrinsic TNFR1 signaling drives the production of monocyte-derived interleukin-1 (IL-1), which signals through IL-1 receptors on non-hematopoietic cells to enable PG-mediated control of intestinal Yersinia infection. Altogether, our work reveals a monocyte-intrinsic TNF-IL-1 collaborative inflammatory circuit that restricts intestinal Yersinia infection.
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Affiliation(s)
- Rina Matsuda
- Department of Pathobiology, School of Veterinary Medicine, University of Pennsylvania, Philadelphia, PA, USA
| | - Daniel Sorobetea
- Department of Pathobiology, School of Veterinary Medicine, University of Pennsylvania, Philadelphia, PA, USA
| | - Jenna Zhang
- Department of Microbiology, Perelman School of Medicine, University of Pennsylvania, Philadelphia, PA, USA
| | - Stefan T. Peterson
- Department of Pathobiology, School of Veterinary Medicine, University of Pennsylvania, Philadelphia, PA, USA
| | - James P. Grayczyk
- Department of Pathobiology, School of Veterinary Medicine, University of Pennsylvania, Philadelphia, PA, USA
| | - Winslow Yost
- Department of Pathobiology, School of Veterinary Medicine, University of Pennsylvania, Philadelphia, PA, USA
| | - Nicolai Apenes
- Department of Pathobiology, School of Veterinary Medicine, University of Pennsylvania, Philadelphia, PA, USA
| | - Maria E. Kovalik
- Department of Pathobiology, School of Veterinary Medicine, University of Pennsylvania, Philadelphia, PA, USA
| | - Beatrice Herrmann
- Department of Pathobiology, School of Veterinary Medicine, University of Pennsylvania, Philadelphia, PA, USA
| | - Rosemary J. O’Neill
- Department of Pathobiology, School of Veterinary Medicine, University of Pennsylvania, Philadelphia, PA, USA
| | - Andrea C. Bohrer
- Inflammation and Innate Immunity Unit, Laboratory of Clinical Immunology and Microbiology, National Institute of Allergy and Infectious Diseases, National Institutes of Health, Bethesda, MD, USA
| | - Matthew Lanza
- Department of Pathobiology, School of Veterinary Medicine, University of Pennsylvania, Philadelphia, PA, USA
| | - Charles-Antoine Assenmacher
- Department of Pathobiology, School of Veterinary Medicine, University of Pennsylvania, Philadelphia, PA, USA
| | - Katrin D. Mayer-Barber
- Inflammation and Innate Immunity Unit, Laboratory of Clinical Immunology and Microbiology, National Institute of Allergy and Infectious Diseases, National Institutes of Health, Bethesda, MD, USA
| | - Sunny Shin
- Department of Microbiology, Perelman School of Medicine, University of Pennsylvania, Philadelphia, PA, USA
| | - Igor E. Brodsky
- Department of Pathobiology, School of Veterinary Medicine, University of Pennsylvania, Philadelphia, PA, USA
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6
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Zhang J, Brodsky IE, Shin S. Yersinia deploys type III-secreted effectors to evade caspase-4 inflammasome activation in human cells. mBio 2023; 14:e0131023. [PMID: 37615436 PMCID: PMC10653943 DOI: 10.1128/mbio.01310-23] [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: 06/15/2023] [Accepted: 07/06/2023] [Indexed: 08/25/2023] Open
Abstract
IMPORTANCE Yersinia are responsible for significant disease burden in humans, ranging from recurrent disease outbreaks (yersiniosis) to pandemics (Yersinia pestis plague). Together with rising antibiotic resistance rates, there is a critical need to better understand Yersinia pathogenesis and host immune mechanisms, as this information will aid in developing improved immunomodulatory therapeutics. Inflammasome responses in human cells are less studied relative to murine models of infection, though recent studies have uncovered key differences in inflammasome responses between mice and humans. Here, we dissect human intestinal epithelial cell and macrophage inflammasome responses to Yersinia pseudotuberculosis. Our findings provide insight into species- and cell type-specific differences in inflammasome responses to Yersinia.
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Affiliation(s)
- Jenna Zhang
- Department of Microbiology, University of Pennsylvania, Perelman School of Medicine, Philadelphia, Pennsylvania, USA
| | - Igor E. Brodsky
- Department of Pathobiology, University of Pennsylvania, School of Veterinary Medicine, Philadelphia, Pennsylvania, USA
| | - Sunny Shin
- Department of Microbiology, University of Pennsylvania, Perelman School of Medicine, Philadelphia, Pennsylvania, USA
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Malik HS, Magnotti F, Loeven NA, Delgado JM, Kettenbach AN, Henry T, Bliska JB. Phosphoprotein phosphatase activity positively regulates oligomeric pyrin to trigger inflammasome assembly in phagocytes. mBio 2023; 14:e0206623. [PMID: 37787552 PMCID: PMC10653879 DOI: 10.1128/mbio.02066-23] [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: 08/08/2023] [Accepted: 08/14/2023] [Indexed: 10/04/2023] Open
Abstract
IMPORTANCE Pyrin, a unique cytosolic receptor, initiates inflammatory responses against RhoA-inactivating bacterial toxins and effectors like Yersinia's YopE and YopT. Understanding pyrin regulation is crucial due to its association with dysregulated inflammatory responses, including Familial Mediterranean Fever (FMF), linked to pyrin gene mutations. FMF mutations historically acted as a defense mechanism against plague. Negative regulation of pyrin through PKN phosphorylation is well established, with Yersinia using the YopM effector to promote pyrin phosphorylation and counteract its activity. This study highlights the importance of phosphoprotein phosphatase activity in positively regulating pyrin inflammasome assembly in phagocytic cells of humans and mice. Oligomeric murine pyrin has S205 phosphorylated before inflammasome assembly, and this study implicates the dephosphorylation of murine pyrin S205 by two catalytic subunits of PP2A in macrophages. These findings offer insights for investigating the regulation of oligomeric pyrin and the balance of kinase and phosphatase activity in pyrin-associated infectious and autoinflammatory diseases.
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Affiliation(s)
- Haleema S. Malik
- Department of Microbiology and Immunology, Geisel School of Medicine at Dartmouth, Hanover, New Hampshire, USA
| | - Flora Magnotti
- CIRI, Centre International de Recherche en Infectiologie, Inserm U111, Université Claude Bernard Lyon, CNRS, UMR5308, ENS de Lyon, Univ Lyon, Lyon, France
| | - Nicole A. Loeven
- Department of Microbiology and Immunology, Geisel School of Medicine at Dartmouth, Hanover, New Hampshire, USA
- Department of Pathology and Laboratory Medicine, Hospital of the University of Pennsylvania, Philadelphia, Pennsylvania, USA
| | - Jose M. Delgado
- Department of Biochemistry and Cell Biology, Geisel School of Medicine at Dartmouth, Hanover, New Hampshire, USA
| | - Arminja N. Kettenbach
- Department of Biochemistry and Cell Biology, Geisel School of Medicine at Dartmouth, Hanover, New Hampshire, USA
- Dartmouth Cancer Center, Lebanon, New Hampshire, USA
| | - Thomas Henry
- CIRI, Centre International de Recherche en Infectiologie, Inserm U111, Université Claude Bernard Lyon, CNRS, UMR5308, ENS de Lyon, Univ Lyon, Lyon, France
| | - James B. Bliska
- Department of Microbiology and Immunology, Geisel School of Medicine at Dartmouth, Hanover, New Hampshire, USA
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Abstract
The immune system of multicellular organisms protects them from harmful microbes. To establish an infection in the face of host immune responses, pathogens must evolve specific strategies to target immune defense mechanisms. One such defense is the formation of intracellular protein complexes, termed inflammasomes, that are triggered by the detection of microbial components and the disruption of homeostatic processes that occur during bacterial infection. Formation of active inflammasomes initiates programmed cell death pathways via activation of inflammatory caspases and cleavage of target proteins. Inflammasome-activated cell death pathways such as pyroptosis lead to proinflammatory responses that protect the host. Bacterial infection has the capacity to influence inflammasomes in two distinct ways: activation and perturbation. In this review, we discuss how bacterial activities influence inflammasomes, and we discuss the consequences of inflammasome activation or evasion for both the host and pathogen.
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Affiliation(s)
- Beatrice I Herrmann
- Department of Pathobiology, School of Veterinary Medicine, University of Pennsylvania, Philadelphia, Pennsylvania, USA; ,
- Cell and Molecular Biology Graduate Group, Perelman School of Medicine, University of Pennsylvania, Philadelphia, Pennsylvania, USA
| | - James P Grayczyk
- Department of Pathobiology, School of Veterinary Medicine, University of Pennsylvania, Philadelphia, Pennsylvania, USA; ,
- Current affiliation: Oncology Discovery, Abbvie, Inc., Chicago, Illinois, USA;
| | - Igor E Brodsky
- Department of Pathobiology, School of Veterinary Medicine, University of Pennsylvania, Philadelphia, Pennsylvania, USA; ,
- Cell and Molecular Biology Graduate Group, Perelman School of Medicine, University of Pennsylvania, Philadelphia, Pennsylvania, USA
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Chai Q, Lei Z, Liu CH. Pyroptosis modulation by bacterial effector proteins. Semin Immunol 2023; 69:101804. [PMID: 37406548 DOI: 10.1016/j.smim.2023.101804] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 03/21/2023] [Revised: 06/28/2023] [Accepted: 06/29/2023] [Indexed: 07/07/2023]
Abstract
Pyroptosis is a proinflammatory form of programmed cell death featured with membrane pore formation that causes cellular swelling and allows the release of intracellular inflammatory mediators. This cell death process is elicited by the activation of the pore-forming proteins named gasdermins, and is intricately orchestrated by diverse regulatory factors in mammalian hosts to exert a prompt immune response against infections. However, growing evidence suggests that bacterial pathogens have evolved to regulate host pyroptosis for evading immune clearance and establishing progressive infection. In this review, we highlight current understandings of the functional role and regulatory network of pyroptosis in host antibacterial immunity. Thereafter, we further discuss the latest advances elucidating the mechanisms by which bacterial pathogens modulate pyroptosis through adopting their effector proteins to drive infections. A better understanding of regulatory mechanisms underlying pyroptosis at the interface of host-bacterial interactions will shed new light on the pathogenesis of infectious diseases and contribute to the development of promising therapeutic strategies against bacterial pathogens.
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Affiliation(s)
- Qiyao Chai
- CAS Key Laboratory of Pathogenic Microbiology and Immunology, Institute of Microbiology, Chinese Academy of Sciences, Beijing 100101, China.
| | - Zehui Lei
- CAS Key Laboratory of Pathogenic Microbiology and Immunology, Institute of Microbiology, Chinese Academy of Sciences, Beijing 100101, China; Savaid Medical School, University of Chinese Academy of Sciences, Beijing 101408, China
| | - Cui Hua Liu
- CAS Key Laboratory of Pathogenic Microbiology and Immunology, Institute of Microbiology, Chinese Academy of Sciences, Beijing 100101, China; Savaid Medical School, University of Chinese Academy of Sciences, Beijing 101408, China.
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Nandi I, Aroeti B. Mitogen-Activated Protein Kinases (MAPKs) and Enteric Bacterial Pathogens: A Complex Interplay. Int J Mol Sci 2023; 24:11905. [PMID: 37569283 PMCID: PMC10419152 DOI: 10.3390/ijms241511905] [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: 06/18/2023] [Revised: 07/19/2023] [Accepted: 07/19/2023] [Indexed: 08/13/2023] Open
Abstract
Diverse extracellular and intracellular cues activate mammalian mitogen-activated protein kinases (MAPKs). Canonically, the activation starts at cell surface receptors and continues via intracellular MAPK components, acting in the host cell nucleus as activators of transcriptional programs to regulate various cellular activities, including proinflammatory responses against bacterial pathogens. For instance, binding host pattern recognition receptors (PRRs) on the surface of intestinal epithelial cells to bacterial pathogen external components trigger the MAPK/NF-κB signaling cascade, eliciting cytokine production. This results in an innate immune response that can eliminate the bacterial pathogen. However, enteric bacterial pathogens evolved sophisticated mechanisms that interfere with such a response by delivering virulent proteins, termed effectors, and toxins into the host cells. These proteins act in numerous ways to inactivate or activate critical components of the MAPK signaling cascades and innate immunity. The consequence of such activities could lead to successful bacterial colonization, dissemination, and pathogenicity. This article will review enteric bacterial pathogens' strategies to modulate MAPKs and host responses. It will also discuss findings attempting to develop anti-microbial treatments by targeting MAPKs.
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Affiliation(s)
| | - Benjamin Aroeti
- Department of Biological Chemistry, Alexander Silberman Institute of Life Sciences, The Hebrew University of Jerusalem, Jerusalem 9190410, Israel;
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Zhang J, Brodsky IE, Shin S. Yersinia Type III-Secreted Effectors Evade the Caspase-4 Inflammasome in Human Cells. BIORXIV : THE PREPRINT SERVER FOR BIOLOGY 2023:2023.01.24.525473. [PMID: 36747770 PMCID: PMC9900831 DOI: 10.1101/2023.01.24.525473] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Grants] [Track Full Text] [Download PDF] [Figures] [Subscribe] [Scholar Register] [Indexed: 01/26/2023]
Abstract
Yersinia are gram-negative zoonotic bacteria that use a type III secretion system (T3SS) to inject Yersinia outer proteins (Yops) into the host cytosol to subvert essential components of innate immune signaling. However, Yersinia virulence activities can elicit activation of inflammasomes, which lead to inflammatory cell death and cytokine release to contain infection. Yersinia activation and evasion of inflammasomes have been characterized in murine macrophages but remain poorly defined in human cells, particularly intestinal epithelial cells (IECs), a primary site of intestinal Yersinia infection. In contrast to murine macrophages, we find that in both human IECs and macrophages, Yersinia pseudotuberculosis T3SS effectors enable evasion of the caspase-4 inflammasome, which senses cytosolic lipopolysaccharide (LPS). The antiphagocytic YopE and YopH, as well as the translocation regulator YopK, were collectively responsible for evading inflammasome activation, in part by inhibiting Yersinia internalization mediated by YadA and β1-integrin signaling. These data provide insight into the mechanisms of Yersinia-mediated inflammasome activation and evasion in human cells, and reveal species-specific differences underlying regulation of inflammasome responses to Yersinia .
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Affiliation(s)
- Jenna Zhang
- Department of Microbiology, University of Pennsylvania Perelman School of Medicine, Philadelphia, Pennsylvania 19104
| | - Igor E. Brodsky
- Department of Pathobiology, University of Pennsylvania School of Veterinary Medicine, Philadelphia, Pennsylvania 19104
| | - Sunny Shin
- Department of Microbiology, University of Pennsylvania Perelman School of Medicine, Philadelphia, Pennsylvania 19104
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12
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Matsuda R, Sorobetea D, Zhang J, Peterson ST, Grayczyk JP, Herrmann B, Yost W, O’Neill R, Bohrer AC, Lanza M, Assenmacher CA, Mayer-Barber KD, Shin S, Brodsky IE. A TNF-IL-1 circuit controls Yersinia within intestinal granulomas. BIORXIV : THE PREPRINT SERVER FOR BIOLOGY 2023:2023.04.21.537749. [PMID: 37197029 PMCID: PMC10176537 DOI: 10.1101/2023.04.21.537749] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Grants] [Track Full Text] [Download PDF] [Figures] [Subscribe] [Scholar Register] [Indexed: 05/19/2023]
Abstract
Tumor necrosis factor (TNF) is a pleiotropic inflammatory cytokine that mediates antimicrobial defense and granuloma formation in response to infection by numerous pathogens. Yersinia pseudotuberculosis colonizes the intestinal mucosa and induces recruitment of neutrophils and inflammatory monocytes into organized immune structures termed pyogranulomas that control the bacterial infection. Inflammatory monocytes are essential for control and clearance of Yersinia within intestinal pyogranulomas, but how monocytes mediate Yersinia restriction is poorly understood. Here, we demonstrate that TNF signaling in monocytes is required for bacterial containment following enteric Yersinia infection. We further show that monocyte-intrinsic TNFR1 signaling drives production of monocyte-derived interleukin-1 (IL-1), which signals through IL-1 receptor on non-hematopoietic cells to enable pyogranuloma-mediated control of Yersinia infection. Altogether, our work reveals a monocyte-intrinsic TNF-IL-1 collaborative circuit as a crucial driver of intestinal granuloma function, and defines the cellular target of TNF signaling that restricts intestinal Yersinia infection.
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Affiliation(s)
- Rina Matsuda
- Department of Pathobiology, School of Veterinary Medicine, University of Pennsylvania, Philadelphia, PA 19104 USA
| | - Daniel Sorobetea
- Department of Pathobiology, School of Veterinary Medicine, University of Pennsylvania, Philadelphia, PA 19104 USA
| | - Jenna Zhang
- Department of Microbiology, Perelman School of Medicine, University of Pennsylvania, Philadelphia, PA 19104 USA
| | - Stefan T. Peterson
- Department of Pathobiology, School of Veterinary Medicine, University of Pennsylvania, Philadelphia, PA 19104 USA
| | - James P. Grayczyk
- Department of Pathobiology, School of Veterinary Medicine, University of Pennsylvania, Philadelphia, PA 19104 USA
| | - Beatrice Herrmann
- Department of Pathobiology, School of Veterinary Medicine, University of Pennsylvania, Philadelphia, PA 19104 USA
| | - Winslow Yost
- Department of Pathobiology, School of Veterinary Medicine, University of Pennsylvania, Philadelphia, PA 19104 USA
| | - Rosemary O’Neill
- Department of Pathobiology, School of Veterinary Medicine, University of Pennsylvania, Philadelphia, PA 19104 USA
| | - Andrea C. Bohrer
- Inflammation and Innate Immunity Unit, Laboratory of Clinical Immunology and Microbiology, National Institute of Allergy and Infectious Diseases, National Institutes of Health, Bethesda, MD 20892, USA
| | - Matthew Lanza
- Department of Pathobiology, School of Veterinary Medicine, University of Pennsylvania, Philadelphia, PA 19104 USA
| | - Charles-Antoine Assenmacher
- Department of Pathobiology, School of Veterinary Medicine, University of Pennsylvania, Philadelphia, PA 19104 USA
| | - Katrin D. Mayer-Barber
- Inflammation and Innate Immunity Unit, Laboratory of Clinical Immunology and Microbiology, National Institute of Allergy and Infectious Diseases, National Institutes of Health, Bethesda, MD 20892, USA
| | - Sunny Shin
- Department of Microbiology, Perelman School of Medicine, University of Pennsylvania, Philadelphia, PA 19104 USA
| | - Igor E. Brodsky
- Department of Pathobiology, School of Veterinary Medicine, University of Pennsylvania, Philadelphia, PA 19104 USA
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13
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Chen KW, Brodsky IE. Yersinia interactions with regulated cell death pathways. Curr Opin Microbiol 2023; 71:102256. [PMID: 36584489 DOI: 10.1016/j.mib.2022.102256] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/12/2022] [Revised: 11/18/2022] [Accepted: 11/30/2022] [Indexed: 12/29/2022]
Abstract
Cell death in response to infection is conserved across all kingdoms of life. In metazoans, cell death upon bacterial infection is primarily carried out by the cysteine and aspartate protease and receptor-interacting serine/threonine protein kinase families. The Gram-negative bacterial genus Yersinia includes pathogens that cause disease in humans and other animals ranging from plague to gastrointestinal infections. Pathogenic Yersiniae express a type-III secretion system (T3SS), which translocates effectors that disrupt phagocytosis and innate immune signaling to evade immune defenses and replicate extracellularly in infected tissues. Blockade of innate immune signaling, disruption of the actin cytoskeleton, and the membrane-disrupting activity of the T3SS translocon pore, are all sensed by innate immune cells. Here, we discuss recent advances in understanding the pathways that regulate Yersinia-induced cell death, and how manipulation of these cell death pathways over the course of infection promotes bacterial dissemination or host defense.
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Affiliation(s)
- Kaiwen W Chen
- Immunology Translational Research Programme, Department of Microbiology and Immunology, Yong Loo Lin School of Medicine, National University of Singapore, Singapore, Singapore; Immunology Programme, Life Sciences Institute, National University of Singapore, Singapore, Singapore
| | - Igor E Brodsky
- Department of Pathobiology, University of Pennsylvania School of Veterinary Medicine, United States; Department of Microbiology, University of Pennsylvania Perelman School of Medicine, United States.
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14
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Selvapandiyan A, Puri N, Kumar P, Alam A, Ehtesham NZ, Griffin G, Hasnain SE. Zooming in on common immune evasion mechanisms of pathogens in phagolysosomes: potential broad-spectrum therapeutic targets against infectious diseases. FEMS Microbiol Rev 2023; 47:6780197. [PMID: 36309472 DOI: 10.1093/femsre/fuac041] [Citation(s) in RCA: 2] [Impact Index Per Article: 2.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/29/2022] [Revised: 10/06/2022] [Accepted: 10/18/2022] [Indexed: 01/19/2023] Open
Abstract
The intracellular viral, bacterial, or parasitic pathogens evade the host immune challenges to propagate and cause fatal diseases. The microbes overpower host immunity at various levels including during entry into host cells, phagosome formation, phagosome maturation, phagosome-lysosome fusion forming phagolysosomes, acidification of phagolysosomes, and at times after escape into the cytosol. Phagolysosome is the final organelle in the phagocyte with sophisticated mechanisms to degrade the pathogens. The immune evasion strategies by the pathogens include the arrest of host cell apoptosis, decrease in reactive oxygen species, the elevation of Th2 anti-inflammatory response, avoidance of autophagy and antigen cross-presentation pathways, and escape from phagolysosomal killing. Since the phagolysosome organelle in relation to infection/cure is seldom discussed in the literature, we summarize here the common host as well as pathogen targets manipulated or utilized by the pathogens established in phagosomes and phagolysosomes, to hijack the host immune system for their benefit. These common molecules or pathways can be broad-spectrum therapeutic targets for drug development for intervention against infectious diseases caused by different intracellular pathogens.
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Affiliation(s)
| | - Niti Puri
- Cellular and Molecular Immunology Laboratory, School of Life Sciences, Jawaharlal Nehru University, New Delhi, 110067, India
| | - Pankaj Kumar
- Department of Biochemistry, Jamia Hamdard, New Delhi, 110062, India.,Centre for Tuberculosis Research, Department of Medicine, Johns Hopkins University, Baltimore, MD, 21218, United States
| | - Anwar Alam
- ICMR-National Institute of Pathology, Safdarjung Hospital Campus, New Delhi, 110029, India.,Department of Biochemical Engineering and Biotechnology, Indian Institute of Technology-Delhi, New Delhi, 110016, India
| | - Nasreen Zafar Ehtesham
- ICMR-National Institute of Pathology, Safdarjung Hospital Campus, New Delhi, 110029, India
| | - George Griffin
- Department of Cellular and Molecular Medicine, St. George's University of London, London, SW17 0RE, United Kingdom
| | - Seyed Ehtesham Hasnain
- Department of Biochemical Engineering and Biotechnology, Indian Institute of Technology-Delhi, New Delhi, 110016, India.,Department of Life Science, School of Basic Sciences and Research, Sharda University, Knowledge Park III, Greater Noida, 201310, India
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15
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Abstract
The major function of the mammalian immune system is to prevent and control infections caused by enteropathogens that collectively have altered human destiny. In fact, as the gastrointestinal tissues are the major interface of mammals with the environment, up to 70% of the human immune system is dedicated to patrolling them The defenses are multi-tiered and include the endogenous microflora that mediate colonization resistance as well as physical barriers intended to compartmentalize infections. The gastrointestinal tract and associated lymphoid tissue are also protected by sophisticated interleaved arrays of active innate and adaptive immune defenses. Remarkably, some bacterial enteropathogens have acquired an arsenal of virulence factors with which they neutralize all these formidable barriers to infection, causing disease ranging from mild self-limiting gastroenteritis to in some cases devastating human disease.
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Affiliation(s)
- Micah J. Worley
- Department of Biology, University of Louisville, Louisville, Kentucky, USA,CONTACT Micah J. Worley Department of Biology, University of Louisville, 139 Life Sciences Bldg, Louisville, Kentucky, USA
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16
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Reprogramming of Cell Death Pathways by Bacterial Effectors as a Widespread Virulence Strategy. Infect Immun 2022; 90:e0061421. [PMID: 35467397 DOI: 10.1128/iai.00614-21] [Citation(s) in RCA: 10] [Impact Index Per Article: 5.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/13/2022] Open
Abstract
The modulation of programmed cell death (PCD) processes during bacterial infections is an evolving arms race between pathogens and their hosts. The initiation of apoptosis, necroptosis, and pyroptosis pathways are essential to immunity against many intracellular and extracellular bacteria. These cellular self-destructive mechanisms are used by the infected host to restrict and eliminate bacterial pathogens. Without a tight regulatory control, host cell death can become a double-edged sword. Inflammatory PCDs contribute to an effective immune response against pathogens, but unregulated inflammation aggravates the damage caused by bacterial infections. Thus, fine-tuning of these pathways is required to resolve infection while preserving the host immune homeostasis. In turn, bacterial pathogens have evolved secreted virulence factors or effector proteins that manipulate PCD pathways to promote infection. In this review, we discuss the importance of controlled cell death in immunity to bacterial infection. We also detail the mechanisms employed by type 3 secreted bacterial effectors to bypass these pathways and their importance in bacterial pathogenesis.
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17
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Fasciano AC, Dasanayake GS, Estes MK, Zachos NC, Breault DT, Isberg RR, Tan S, Mecsas J. Yersinia pseudotuberculosis YopE prevents uptake by M cells and instigates M cell extrusion in human ileal enteroid-derived monolayers. Gut Microbes 2022; 13:1988390. [PMID: 34793276 PMCID: PMC8604394 DOI: 10.1080/19490976.2021.1988390] [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] [Submit a Manuscript] [Subscribe] [Scholar Register] [Indexed: 02/04/2023] Open
Abstract
Many pathogens use M cells to access the underlying Peyer's patches and spread to systemic sites via the lymph as demonstrated by ligated loop murine intestinal models. However, the study of interactions between M cells and microbial pathogens has stalled due to the lack of cell culture systems. To overcome this obstacle, we use human ileal enteroid-derived monolayers containing five intestinal cell types including M cells to study the interactions between the enteric pathogen, Yersinia pseudotuberculosis (Yptb), and M cells. The Yptb type three secretion system (T3SS) effector Yops inhibit host defenses including phagocytosis and are critical for colonization of the intestine and Peyer's patches. Therefore, it is not understood how Yptb traverses through M cells to breach the epithelium. By growing Yptb under two physiological conditions that mimic the early infectious stage (low T3SS-expression) or host-adapted stage (high T3SS-expression), we found that large numbers of Yptb specifically associated with M cells, recapitulating murine studies. Transcytosis through M cells was significantly higher by Yptb expressing low levels of T3SS, because YopE and YopH prevented Yptb uptake. YopE also caused M cells to extrude from the epithelium without inducing cell-death or disrupting monolayer integrity. Sequential infection with early infectious stage Yptb reduced host-adapted Yptb association with M cells. These data underscore the strength of enteroids as a model by discovering that Yops impede M cell function, indicating that early infectious stage Yptb more effectively penetrates M cells while the host may defend against M cell penetration of host-adapted Yptb.
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Affiliation(s)
- Alyssa C. Fasciano
- Graduate Program in Immunology, Tufts Graduate School of Biomedical Sciences, Boston, USA
| | - Gaya S. Dasanayake
- Department of Molecular Biology and Microbiology, Tufts University School of Medicine, Boston, USA
| | - Mary K. Estes
- Department of Molecular Virology and Microbiology, Baylor College of Medicine, Houston, USA
| | - Nicholas C. Zachos
- Department of Medicine, Division of Gastroenterology and Hepatology, Johns Hopkins University School of Medicine, Baltimore, USA
| | - David T. Breault
- Division of Endocrinology, Boston Children’s Hospital, Department of Pediatrics, Harvard Medical School, Boston, USA
| | - Ralph R. Isberg
- Graduate Program in Immunology, Tufts Graduate School of Biomedical Sciences, Boston, USA,Department of Molecular Biology and Microbiology, Tufts University School of Medicine, Boston, USA
| | - Shumin Tan
- Department of Molecular Biology and Microbiology, Tufts University School of Medicine, Boston, USA
| | - Joan Mecsas
- Graduate Program in Immunology, Tufts Graduate School of Biomedical Sciences, Boston, USA,Department of Molecular Biology and Microbiology, Tufts University School of Medicine, Boston, USA,CONTACT Joan Mecsas Department of Molecular Biology and Microbiology, Tufts University School of Medicine, Boston, USA
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18
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Role of the Yersinia pseudotuberculosis Virulence Plasmid in Pathogen-Phagocyte Interactions in Mesenteric Lymph Nodes. EcoSal Plus 2021; 9:eESP00142021. [PMID: 34910573 DOI: 10.1128/ecosalplus.esp-0014-2021] [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] [Indexed: 12/21/2022]
Abstract
Yersinia pseudotuberculosis is an Enterobacteriaceae family member that is commonly transmitted by the fecal-oral route to cause infections. From the small intestine, Y. pseudotuberculosis can invade through Peyer's patches and lymph vessels to infect the mesenteric lymph nodes (MLNs). Infection of MLNs by Y. pseudotuberculosis results in the clinical presentation of mesenteric lymphadenitis. MLNs are important for immune responses to intestinal pathogens and microbiota in addition to their clinical relevance to Y. pseudotuberculosis infections. A characteristic of Y. pseudotuberculosis infection in MLNs is the formation of pyogranulomas. Pyogranulomas are composed of neutrophils, inflammatory monocytes, and lymphocytes surrounding extracellular microcolonies of Y. pseudotuberculosis. Key elements of the complex pathogen-host interaction in MLNs have been identified using mouse infection models. Y. pseudotuberculosis requires the virulence plasmid pYV to induce the formation of pyogranulomas in MLNs. The YadA adhesin and the Ysc-Yop type III secretion system (T3SS) are encoded on pYV. YadA mediates bacterial binding to host receptors, which engages the T3SS to preferentially translocate seven Yop effectors into phagocytes. The effectors promote pathogenesis by blocking innate immune defenses such as superoxide production, degranulation, and inflammasome activation, resulting in survival and growth of Y. pseudotuberculosis. On the other hand, certain effectors can trigger immune defenses in phagocytes. For example, YopJ triggers activation of caspase-8 and an apoptotic cell death response in monocytes within pyogranulomas that limits dissemination of Y. pseudotuberculosis from MLNs to the bloodstream. YopE can be processed as an antigen by phagocytes in MLNs, resulting in T and B cell responses to Y. pseudotuberculosis. Immune responses to Y. pseudotuberculosis in MLNs can also be detrimental to the host in the form of chronic lymphadenopathy. This review focuses on interactions between Y. pseudotuberculosis and phagocytes mediated by pYV that concurrently promote pathogenesis and host defense in MLNs. We propose that MLN pyogranulomas are immunological arenas in which opposing pYV-driven forces determine the outcome of infection in favor of the pathogen or host.
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19
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Pienkoß S, Javadi S, Chaoprasid P, Nolte T, Twittenhoff C, Dersch P, Narberhaus F. The gatekeeper of Yersinia type III secretion is under RNA thermometer control. PLoS Pathog 2021; 17:e1009650. [PMID: 34767606 PMCID: PMC8612567 DOI: 10.1371/journal.ppat.1009650] [Citation(s) in RCA: 4] [Impact Index Per Article: 1.3] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/12/2021] [Revised: 11/24/2021] [Accepted: 10/27/2021] [Indexed: 01/03/2023] Open
Abstract
Many bacterial pathogens use a type III secretion system (T3SS) as molecular syringe to inject effector proteins into the host cell. In the foodborne pathogen Yersinia pseudotuberculosis, delivery of the secreted effector protein cocktail through the T3SS depends on YopN, a molecular gatekeeper that controls access to the secretion channel from the bacterial cytoplasm. Here, we show that several checkpoints adjust yopN expression to virulence conditions. A dominant cue is the host body temperature. A temperature of 37°C is known to induce the RNA thermometer (RNAT)-dependent synthesis of LcrF, a transcription factor that activates expression of the entire T3SS regulon. Here, we uncovered a second layer of temperature control. We show that another RNAT silences translation of the yopN mRNA at low environmental temperatures. The long and short 5’-untranslated region of both cellular yopN isoforms fold into a similar secondary structure that blocks ribosome binding. The hairpin structure with an internal loop melts at 37°C and thereby permits formation of the translation initiation complex as shown by mutational analysis, in vitro structure probing and toeprinting methods. Importantly, we demonstrate the physiological relevance of the RNAT in the faithful control of type III secretion by using a point-mutated thermostable RNAT variant with a trapped SD sequence. Abrogated YopN production in this strain led to unrestricted effector protein secretion into the medium, bacterial growth arrest and delayed translocation into eukaryotic host cells. Cumulatively, our results show that substrate delivery by the Yersinia T3SS is under hierarchical surveillance of two RNATs. Temperature serves as reliable external cue for pathogenic bacteria to recognize the entry into or exit from a warm-blooded host. At the molecular level, a temperature of 37°C induces various virulence-related processes that manipulate host cell physiology. Here, we demonstrate the temperature-dependent synthesis of the secretion regulator YopN in the foodborne pathogen Yersinia pseudotuberculosis, a close relative of Yersinia pestis. YopN blocks secretion of effector proteins through the type III secretion system unless host cell contact is established. Temperature-specific regulation relies on an RNA structure in the 5’-untranslated region of the yopN mRNA, referred to as RNA thermometer, which allows ribosome binding and thus translation initiation only at an infection-relevant temperature of 37°C. A mutated variant of the thermosensor resulting in a closed conformation prevented synthesis of the molecular gatekeeper YopN and led to permanent secretion and defective translocation of virulence factors into host cells. We suggest that the RNA thermometer plays a critical role in adjusting the optimal cellular concentration of a surveillance factor that maintains the controlled translocation of virulence factors.
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Affiliation(s)
| | - Soheila Javadi
- Microbial Biology, Ruhr University Bochum, Bochum, Germany
| | - Paweena Chaoprasid
- Institute of Infectiology, Center for Molecular Biology of Inflammation (ZMBE), University of Münster, Münster, Germany
| | - Thomas Nolte
- Microbial Biology, Ruhr University Bochum, Bochum, Germany
| | - Christian Twittenhoff
- Microbial Biology, Ruhr University Bochum, Bochum, Germany.,Rottendorf Pharma GmbH, Ennigerloh, Germany
| | - Petra Dersch
- Institute of Infectiology, Center for Molecular Biology of Inflammation (ZMBE), University of Münster, Münster, Germany
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20
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Mikaty G, Coullon H, Fiette L, Pizarro-Cerdá J, Carniel E. The invasive pathogen Yersinia pestis disrupts host blood vasculature to spread and provoke hemorrhages. PLoS Negl Trop Dis 2021; 15:e0009832. [PMID: 34610007 PMCID: PMC8519436 DOI: 10.1371/journal.pntd.0009832] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/17/2021] [Revised: 10/15/2021] [Accepted: 09/22/2021] [Indexed: 11/29/2022] Open
Abstract
Yersinia pestis is a powerful pathogen with a rare invasive capacity. After a flea bite, the plague bacillus can reach the bloodstream in a matter of days giving way to invade the whole organism reaching all organs and provoking disseminated hemorrhages. However, the mechanisms used by this bacterium to cross and disrupt the endothelial vascular barrier remain poorly understood. In this study, an innovative model of in vivo infection was used to focus on the interaction between Y. pestis and its host vascular system. In the draining lymph nodes and in secondary organs, bacteria provoked the porosity and disruption of blood vessels. An in vitro model of endothelial barrier showed a role in this phenotype for the pYV/pCD1 plasmid that carries a Type Three Secretion System. This work supports that the pYV/pCD1 plasmid is responsible for the powerful tissue invasiveness capacity of the plague bacillus and the hemorrhagic features of plague. The plague bacillus, Yersinia pestis, is a powerful pathogen with a rare invasive capacity and is among the few bacteria capable to provoke disseminated hemorrhages. However, the mechanisms used by this bacterium to cross and disrupt the endothelial vascular barrier remain poorly understood. Recent technical progress in microscopy, associated with the use of original fluorescent mutant in mice, allowed us to develop an innovative model of infection in vivo. This model permitted to look directly into the interaction between Y. pestis and its host vascular system, in 3D reconstructed tissues without physical alteration. We were able to observe the degradation of blood vessels in the draining lymph nodes and to visualize the spreading of the bacteria into secondary organs directly through the vascular barrier. Classical in vitro experiments validated the in vivo observation and demonstrated the role of some of the bacterial components in this phenotype. This work shows an unprecedented visualization of the pathogenesis of Y. pestis and decipher part of the powerful invasiveness capacity of the plague bacillus and the hemorrhagic features of plague.
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Affiliation(s)
- Guillain Mikaty
- Institut Pasteur, Yersinia Research Unit, Paris, France
- * E-mail:
| | | | - Laurence Fiette
- Institut Pasteur, Unité d’histopathologie humaine et modèles animaux, Paris, France
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21
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Palace SG, Vitseva O, Proulx MK, Freedman JE, Goguen JD, Koupenova M. Yersinia pestis escapes entrapment in thrombi by targeting platelet function. J Thromb Haemost 2020; 18:3236-3248. [PMID: 33470041 PMCID: PMC8040536 DOI: 10.1111/jth.15065] [Citation(s) in RCA: 3] [Impact Index Per Article: 0.8] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/29/2020] [Revised: 07/15/2020] [Accepted: 07/24/2020] [Indexed: 12/13/2022]
Abstract
BACKGROUND Platelets are classically recognized for their role in hemostasis and thrombosis. Recent work has demonstrated that platelets can also execute a variety of immune functions. The dual prothrombotic and immunological roles of platelets suggest that they may pose a barrier to the replication or dissemination of extracellular bacteria. However, some bloodborne pathogens, such as the plague bacterium Yersinia pestis, routinely achieve high vascular titers that are necessary for pathogen transmission. OBJECTIVES It is not currently known how or if pathogens circumvent platelet barriers to bacterial dissemination and replication. We sought to determine whether extracellular bloodborne bacterial pathogens actively interfere with platelet function, using Y pestis as a model system. METHODS The interactions and morphological changes of human platelets with various genetically modified Y pestis strains were examined using aggregation assays, immunofluorescence, and scanning electron microscopy. RESULTS Yersinia pestis directly destabilized platelet thrombi, preventing bacterial entrapment in fibrin/platelet clots. This activity was dependent on two well-characterized bacterial virulence factors: the Y pestis plasminogen activator Pla, which stimulates host-mediated fibrinolysis, and the bacterial type III secretion system (T3SS), which delivers bacterial proteins into the cytoplasm of targeted host cells to reduce or prevent effective immunological responses. Platelets intoxicated by the Y pestis T3SS were unable to respond to prothrombotic stimuli, and T3SS expression decreased the formation of neutrophil extracellular traps in platelet thrombi. CONCLUSIONS These findings are the first demonstration of a bacterial pathogen using its T3SS and an endogenous protease to manipulate platelet function and to escape entrapment in platelet thrombi.
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Affiliation(s)
- Samantha G. Palace
- Department of Microbiology and Physiological Systems, University of Massachusetts Medical School, Worcester, MA, USA
| | - Olga Vitseva
- Department of Medicine, Division of Cardiovascular Medicine, University of Massachusetts Medical School, Worcester, MA, USA
| | - Megan K. Proulx
- Department of Microbiology and Physiological Systems, University of Massachusetts Medical School, Worcester, MA, USA
| | - Jane E. Freedman
- Department of Medicine, Division of Cardiovascular Medicine, University of Massachusetts Medical School, Worcester, MA, USA
| | - Jon D. Goguen
- Department of Microbiology and Physiological Systems, University of Massachusetts Medical School, Worcester, MA, USA
| | - Milka Koupenova
- Department of Medicine, Division of Cardiovascular Medicine, University of Massachusetts Medical School, Worcester, MA, USA
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22
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Schubert KA, Xu Y, Shao F, Auerbuch V. The Yersinia Type III Secretion System as a Tool for Studying Cytosolic Innate Immune Surveillance. Annu Rev Microbiol 2020; 74:221-245. [PMID: 32660389 DOI: 10.1146/annurev-micro-020518-120221] [Citation(s) in RCA: 7] [Impact Index Per Article: 1.8] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/09/2022]
Abstract
Microbial pathogens have evolved complex mechanisms to interface with host cells in order to evade host defenses and replicate. However, mammalian innate immune receptors detect the presence of molecules unique to the microbial world or sense the activity of virulence factors, activating antimicrobial and inflammatory pathways. We focus on how studies of the major virulence factor of one group of microbial pathogens, the type III secretion system (T3SS) of human pathogenic Yersinia, have shed light on these important innate immune responses. Yersinia are largely extracellular pathogens, yet they insert T3SS cargo into target host cells that modulate the activity of cytosolic innate immune receptors. This review covers both the host pathways that detect the Yersinia T3SS and the effector proteins used by Yersinia to manipulate innate immune signaling.
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Affiliation(s)
- Katherine Andrea Schubert
- Department of Microbiology and Environmental Toxicology, University of California, Santa Cruz, Santa Cruz, California 95064, USA;
| | - Yue Xu
- National Institute of Biological Sciences, Beijing 102206, China
| | - Feng Shao
- National Institute of Biological Sciences, Beijing 102206, China
| | - Victoria Auerbuch
- Department of Microbiology and Environmental Toxicology, University of California, Santa Cruz, Santa Cruz, California 95064, USA;
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23
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Malik HS, Bliska JB. The pyrin inflammasome and the Yersinia effector interaction. Immunol Rev 2020; 297:96-107. [PMID: 32721043 DOI: 10.1111/imr.12907] [Citation(s) in RCA: 16] [Impact Index Per Article: 4.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/07/2020] [Accepted: 07/08/2020] [Indexed: 12/11/2022]
Abstract
Pyrin is a cytosolic pattern-recognition receptor that normally functions as a guard to trigger capase-1 inflammasome assembly in response to bacterial toxins and effectors that inactivate RhoA. The MEFV gene encoding human pyrin is preferentially expressed in phagocytes. Key domains in pyrin include a pyrin domain (PYD), a linker region, and a B30.2 domain. Binding of ASC to pyrin by a PYD-PYD interaction triggers inflammasome assembly. Pyrin is held in an inactive conformation by negative regulation mechanisms to avoid premature inflammasome assembly. One mechanism of negative regulation involves phosphorylation of the linker by PRK kinase which in turn is positively regulated by active RhoA. The B30.2 domain also negatively regulates pyrin. Gain of function mutations in MEFV responsible for the autoinflammatory disease Familial Mediterranean Fever (FMF) map to exon 10 encoding the B30.2 domain. Insights into pyrin regulation have come from studies of several Yersinia effectors, which are injected into phagocytes and interact with the RhoA-PRK-pyrin axis during infection. Two effectors, YopE and YopT, inactivate RhoA to disrupt phagocytic signaling. To counteract an effector-triggered immune response, a third effector, YopM, binds to and inhibits pyrin by hijacking PRK and RSK and directing linker phosphorylation. Inhibition of pyrin by YopM is required for virulence of Yersinia pestis, the agent of plague. Recent results from infection studies with human phagocytes and mice producing pyrin B30.2 FMF variants show that gain of function MEFV mutations bypass inhibition by YopM. Population genetic data suggest that MEFV mutations were selected for in individuals of Mediterranean decent during historic plague pandemics. This review discusses current concepts of pyrin regulation and its interaction with Yersinia effectors.
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Affiliation(s)
- Haleema S Malik
- Department of Microbiology and Immunology, Geisel School of Medicine at Dartmouth, Hanover, NH, USA
| | - James B Bliska
- Department of Microbiology and Immunology, Geisel School of Medicine at Dartmouth, Hanover, NH, USA
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24
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Du J, Lin Z, Volovych O, Lu Z, Zou Z. A RhoGAP venom protein from Microplitis mediator suppresses the cellular response of its host Helicoverpa armigera. DEVELOPMENTAL AND COMPARATIVE IMMUNOLOGY 2020; 108:103675. [PMID: 32173445 DOI: 10.1016/j.dci.2020.103675] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 10/10/2019] [Revised: 03/09/2020] [Accepted: 03/09/2020] [Indexed: 06/10/2023]
Abstract
Female parasitoid wasps normally inject virulence factors together with eggs into their host to counter host immunity defenses. A newly identified RhoGAP protein in the venom of Microplitis mediator compromises the cellular immunity of its host, Helicoverpa armigera. RhoGAP1 proteins entered H. armigera hemocytes, and the host cellular cytoskeleton was disrupted. Depletion of MmGAP1 by injection of dsRNA or antibody increased the wasp egg encapsulation rate. An immunoprecipitation assay of overexpressed MmGAP1 protein in a Helicoverpa cell line showed that MmGAP1 interacts with many cellular cytoskeleton associated proteins as well as Rho GTPases. A yeast two-hybrid and a pull-down assay demonstrated that MmGAP1 interacts with H. armigera RhoA and Cdc42. These results show that the RhoGAP protein in M. mediator can destroy the H. armigera hemocyte cellular cytoskeleton, restrain host cellular immune defense, and increase the probability of successful parasitism.
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Affiliation(s)
- Jie Du
- State Key Laboratory of Integrated Management of Pest Insects and Rodents, Institute of Zoology, Chinese Academy of Sciences, Beijing, 100101, China; CAS Center for Excellence in Biotic Interactions, University of Chinese Academy of Sciences, Beijing, 100049, China
| | - Zhe Lin
- State Key Laboratory of Integrated Management of Pest Insects and Rodents, Institute of Zoology, Chinese Academy of Sciences, Beijing, 100101, China
| | - Olga Volovych
- State Key Laboratory of Integrated Management of Pest Insects and Rodents, Institute of Zoology, Chinese Academy of Sciences, Beijing, 100101, China; CAS Center for Excellence in Biotic Interactions, University of Chinese Academy of Sciences, Beijing, 100049, China
| | - Zhiqiang Lu
- Department of Entomology, College of Plant Protection, Northwest A&F University, Yangling, Shaanxi, 712100, China
| | - Zhen Zou
- State Key Laboratory of Integrated Management of Pest Insects and Rodents, Institute of Zoology, Chinese Academy of Sciences, Beijing, 100101, China; CAS Center for Excellence in Biotic Interactions, University of Chinese Academy of Sciences, Beijing, 100049, China; Key Laboratory of Vector Biology and Pathogen Control of Zhejiang Province, Huzhou University, Huzhou, 311300, China.
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25
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Whelan R, McVicker G, Leo JC. Staying out or Going in? The Interplay between Type 3 and Type 5 Secretion Systems in Adhesion and Invasion of Enterobacterial Pathogens. Int J Mol Sci 2020; 21:E4102. [PMID: 32521829 PMCID: PMC7312957 DOI: 10.3390/ijms21114102] [Citation(s) in RCA: 7] [Impact Index Per Article: 1.8] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/12/2020] [Revised: 06/03/2020] [Accepted: 06/05/2020] [Indexed: 12/12/2022] Open
Abstract
Enteric pathogens rely on a variety of toxins, adhesins and other virulence factors to cause infections. Some of the best studied pathogens belong to the Enterobacterales order; these include enteropathogenic and enterohemorrhagic Escherichia coli, Shigella spp., and the enteropathogenic Yersiniae. The pathogenesis of these organisms involves two different secretion systems, a type 3 secretion system (T3SS) and type 5 secretion systems (T5SSs). The T3SS forms a syringe-like structure spanning both bacterial membranes and the host cell plasma membrane that translocates toxic effector proteins into the cytoplasm of the host cell. T5SSs are also known as autotransporters, and they export part of their own polypeptide to the bacterial cell surface where it exerts its function, such as adhesion to host cell receptors. During infection with these enteropathogens, the T3SS and T5SS act in concert to bring about rearrangements of the host cell cytoskeleton, either to invade the cell, confer intracellular motility, evade phagocytosis or produce novel structures to shelter the bacteria. Thus, in these bacteria, not only the T3SS effectors but also T5SS proteins could be considered "cytoskeletoxins" that bring about profound alterations in host cell cytoskeletal dynamics and lead to pathogenic outcomes.
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Affiliation(s)
| | | | - Jack C. Leo
- Antimicrobial Resistance, Omics and Microbiota Group, Department of Biosciences, Nottingham Trent University, Nottingham NG1 4FQ, UK; (R.W.); (G.M.)
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Huber P. Targeting of the apical junctional complex by bacterial pathogens. BIOCHIMICA ET BIOPHYSICA ACTA-BIOMEMBRANES 2020; 1862:183237. [DOI: 10.1016/j.bbamem.2020.183237] [Citation(s) in RCA: 7] [Impact Index Per Article: 1.8] [Reference Citation Analysis] [Track Full Text] [Subscribe] [Scholar Register] [Received: 09/17/2019] [Revised: 02/06/2020] [Accepted: 02/10/2020] [Indexed: 12/17/2022]
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Fluorescence-Reported Allelic Exchange Mutagenesis-Mediated Gene Deletion Indicates a Requirement for Chlamydia trachomatis Tarp during In Vivo Infectivity and Reveals a Specific Role for the C Terminus during Cellular Invasion. Infect Immun 2020; 88:IAI.00841-19. [PMID: 32152196 DOI: 10.1128/iai.00841-19] [Citation(s) in RCA: 11] [Impact Index Per Article: 2.8] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/04/2019] [Accepted: 03/03/2020] [Indexed: 02/04/2023] Open
Abstract
The translocated actin recruiting phosphoprotein (Tarp) is a multidomain type III secreted effector used by Chlamydia trachomatis In aggregate, existing data suggest a role of this effector in initiating new infections. As new genetic tools began to emerge to study chlamydial genes in vivo, we speculated as to what degree Tarp function contributes to Chlamydia's ability to parasitize mammalian host cells. To address this question, we generated a complete tarP deletion mutant using the fluorescence-reported allelic exchange mutagenesis (FRAEM) technique and complemented the mutant in trans with wild-type tarP or mutant tarP alleles engineered to harbor in-frame domain deletions. We provide evidence for the significant role of Tarp in C. trachomatis invasion of host cells. Complementation studies indicate that the C-terminal filamentous actin (F-actin)-binding domains are responsible for Tarp-mediated invasion efficiency. Wild-type C. trachomatis entry into HeLa cells resulted in host cell shape changes, whereas the tarP mutant did not. Finally, using a novel cis complementation approach, C. trachomatis lacking tarP demonstrated significant attenuation in a murine genital tract infection model. Together, these data provide definitive genetic evidence for the critical role of the Tarp F-actin-binding domains in host cell invasion and for the Tarp effector as a bona fide C. trachomatis virulence factor.
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Lacey CA, Miao EA. Programmed Cell Death in the Evolutionary Race against Bacterial Virulence Factors. Cold Spring Harb Perspect Biol 2020; 12:cshperspect.a036459. [PMID: 31501197 DOI: 10.1101/cshperspect.a036459] [Citation(s) in RCA: 22] [Impact Index Per Article: 5.5] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/17/2022]
Abstract
Innate immune sensors can recognize when host cells are irrevocably compromised by pathogens, and in response can trigger programmed cell death (pyroptosis, apoptosis, and necroptosis). Innate sensors can directly bind microbial ligands; for example, NAIP/NLRC4 detects flagellin/rod/needle, whereas caspase-11 detects lipopolysaccharide. Other sensors are guards that monitor normal function of cellular proteins; for instance, pyrin monitors Rho GTPases, whereas caspase-8 and receptor-interacting protein kinase (RIPK)3 guards RIPK1 transcriptional signaling. Some proteins that need to be guarded can be duplicated as decoy domains, as seen in the integrated decoy domains within NLRP1 that watch for microbial attack. Here, we discuss the evolutionary battle between pathogens and host innate immune sensors/guards, illustrated by the Red Queen hypothesis. We discuss in depth four pathogens, and how they either fail in this evolutionary race (Chromobacterium violaceum, Burkholderia thailandensis), or how the evolutionary race generates increasingly complex virulence factors and host innate immune signaling pathways (Yersinia species, and enteropathogenic Escherichia coli [EPEC]).
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Affiliation(s)
- Carolyn A Lacey
- Department of Microbiology and Immunology, Center for Gastrointestinal Biology and Disease, and Lineberger Comprehensive Cancer Center, University of North Carolina at Chapel Hill, Chapel Hill, North Carolina 27599, USA
| | - Edward A Miao
- Department of Microbiology and Immunology, Center for Gastrointestinal Biology and Disease, and Lineberger Comprehensive Cancer Center, University of North Carolina at Chapel Hill, Chapel Hill, North Carolina 27599, USA
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Eichelberger KR, Jones GS, Goldman WE. Inhibition of Neutrophil Primary Granule Release during Yersinia pestis Pulmonary Infection. mBio 2019; 10:e02759-19. [PMID: 31822588 PMCID: PMC6904878 DOI: 10.1128/mbio.02759-19] [Citation(s) in RCA: 20] [Impact Index Per Article: 4.0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/16/2019] [Accepted: 10/21/2019] [Indexed: 12/22/2022] Open
Abstract
Inhalation of Yersinia pestis causes primary pneumonic plague, the most severe manifestation of plague that is characterized by a dramatic neutrophil influx to the lungs. Neutrophils are ineffective during primary pneumonic plague, failing to control Y. pestis growth in the airways. However, the mechanisms by which Y. pestis resists neutrophil killing are incompletely understood. Here, we show that Y. pestis inhibits neutrophil degranulation, an important line of host innate immune defense. We observed that neutrophils from the lungs of mice infected intranasally with Y. pestis fail to release primary granules throughout the course of disease. Using a type III secretion system (T3SS) injection reporter strain, we determined that Y. pestis directly inhibits neutrophil granule release by a T3SS-dependent mechanism. Combinatorial mutant analysis revealed that a Y. pestis strain lacking both effectors YopE and YopH did not inhibit primary granule release and is killed by neutrophils both in vivo and in vitro Similarly, Y. pestis strains injecting only YopE or YopH are able to inhibit the majority of primary granule release from human neutrophils. We determined that YopE and YopH block Rac2 activation and calcium flux, respectively, to inhibit neutrophil primary granule release in isolated human neutrophils. These results demonstrate that Y. pestis coordinates the inhibition of neutrophil primary granule release through the activities of two distinct effectors, and this inhibition promotes Y. pestis survival during primary pneumonic plague.IMPORTANCEYersinia pestis is the causative agent of plague and is one of the deadliest human pathogens. The pneumonic form of Y. pestis infection has played a critical role in the severity of both historical and modern plague outbreaks, yet the host-pathogen interactions that govern the lethality of Yersinia pestis pulmonary infections are incompletely understood. Here, we report that Yersinia pestis inhibits neutrophil degranulation during infection, rendering neutrophils ineffective and allowing unrestricted growth of Y. pestis in the lungs. This coordinated inhibition of granule release not only demonstrates the pathogenic benefit of "silencing" lung neutrophils but also reveals specific host processes and pathways that could be manipulated to reduce the severity of primary pneumonic plague.
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Affiliation(s)
- Kara R Eichelberger
- Department of Microbiology and Immunology, University of North Carolina at Chapel Hill, Chapel Hill, North Carolina, USA
| | - Grant S Jones
- Department of Microbiology and Immunology, University of North Carolina at Chapel Hill, Chapel Hill, North Carolina, USA
| | - William E Goldman
- Department of Microbiology and Immunology, University of North Carolina at Chapel Hill, Chapel Hill, North Carolina, USA
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Characterization of Pyrin Dephosphorylation and Inflammasome Activation in Macrophages as Triggered by the Yersinia Effectors YopE and YopT. Infect Immun 2019; 87:IAI.00822-18. [PMID: 30602502 DOI: 10.1128/iai.00822-18] [Citation(s) in RCA: 20] [Impact Index Per Article: 4.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/12/2018] [Accepted: 12/14/2018] [Indexed: 01/24/2023] Open
Abstract
Pathogenic Yersinia species deliver Yop effector proteins through a type III secretion system into host cells. Among these effectors, YopE and YopT are Rho-modifying toxins, which function to modulate host cell physiology and evade immune responses. YopE is a GTPase-activating protein (GAP) while YopT is a protease, and they inhibit RhoA by different modes of action. Modifications to RhoA are sensed by pyrin, which, once activated, assembles a caspase-1 inflammasome, which generates cytokines such as interleukin-1β (IL-1β) and cell death by pyroptosis. In Yersinia-infected macrophages, YopE or YopT triggers inflammasome assembly only in the absence of another effector, YopM, which counteracts pyrin by keeping it inactive. The glucosyltransferase TcdB from Clostridium difficile, a well-studied RhoA-inactivating toxin, triggers activation of murine pyrin by dephosphorylation of Ser205 and Ser241. To determine if YopE or YopT triggers pyrin dephosphorylation, we infected lipopolysaccharide (LPS)-primed murine macrophages with ΔyopM Yersinia pseudotuberculosis strains expressing wild-type (wt) or YopE mutant variants or YopT. By immunoblotting pyrin after infection, we observed that wt YopE triggered dephosphorylation of Ser205 and inflammasome activation. Pyrin dephosphorylation was reduced if a YopE variant had a defect in stability or RhoA specificity but not membrane localization. We also observed that wt YopT triggered pyrin dephosphorylation but more slowly than YopE, suggesting that YopE is dominant in this process. Our findings provide evidence that RhoA-modifying toxins trigger activation of pyrin by a conserved dephosphorylation mechanism. In addition, by characterization of YopE and YopT, we show that different features of effectors, such as RhoA specificity, affect the efficiency of pyrin dephosphorylation.
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Methods for Detection of Pyrin Inflammasome Assembly in Macrophages Infected with Yersinia spp. Methods Mol Biol 2019; 2010:241-255. [PMID: 31177443 DOI: 10.1007/978-1-4939-9541-7_17] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.2] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/31/2022]
Abstract
The Yersinia effector proteins YopE and YopT are important bacterial virulence factors that are secreted into infected host cells and can inactivate Rho GTPases, like RhoA, Rac1, and Cdc42. In order to compensate for the consequences of this effect, the host cell can sense RhoA modifications and trigger a proinflammatory reaction to control the infection. This host response, known as pyrin inflammasome assembly, is normally prevented by another important effector, YopM, allowing Yersinia to counteract this conserved innate immune response. Once assembled, the pyrin inflammasome can activate caspase-1 via proteolysis, leading to IL-1β secretion and cell death through pyroptosis. Here we describe how to measure pyrin inflammasome assembly, in response to YopE or YopT activities, when macrophages are infected with yopM mutant Yersinia. Using primary mouse macrophages as host cells, we show how to detect this host response through the downstream events of pyrin dephosphorylation, caspase-1 proteolysis, IL-1β release, and pyroptosis.
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Nauth T, Huschka F, Schweizer M, Bosse JB, Diepold A, Failla AV, Steffen A, Stradal TEB, Wolters M, Aepfelbacher M. Visualization of translocons in Yersinia type III protein secretion machines during host cell infection. PLoS Pathog 2018; 14:e1007527. [PMID: 30586431 PMCID: PMC6324820 DOI: 10.1371/journal.ppat.1007527] [Citation(s) in RCA: 22] [Impact Index Per Article: 3.7] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/14/2018] [Revised: 01/08/2019] [Accepted: 12/14/2018] [Indexed: 12/13/2022] Open
Abstract
Type III secretion systems (T3SSs) are essential virulence factors of numerous bacterial pathogens. Upon host cell contact the T3SS machinery—also named injectisome—assembles a pore complex/translocon within host cell membranes that serves as an entry gate for the bacterial effectors. Whether and how translocons are physically connected to injectisome needles, whether their phenotype is related to the level of effector translocation and which target cell factors trigger their formation have remained unclear. We employed the superresolution fluorescence microscopy techniques Stimulated Emission Depletion (STED) and Structured Illumination Microscopy (SIM) as well as immunogold electron microscopy to visualize Y. enterocolitica translocons during infection of different target cell types. Thereby we were able to resolve translocon and needle complex proteins within the same injectisomes and demonstrate that these fully assembled injectisomes are generated in a prevacuole, a PI(4,5)P2 enriched host cell compartment inaccessible to large extracellular proteins like antibodies. Furthermore, the operable translocons were produced by the yersiniae to a much larger degree in macrophages (up to 25% of bacteria) than in HeLa cells (2% of bacteria). However, when the Rho GTPase Rac1 was activated in the HeLa cells, uptake of the yersiniae into the prevacuole, translocon formation and effector translocation were strongly enhanced reaching the same levels as in macrophages. Our findings indicate that operable T3SS translocons can be visualized as part of fully assembled injectisomes with superresolution fluorescence microscopy techniques. By using this technology, we provide novel information about the spatiotemporal organization of T3SS translocons and their regulation by host cell factors. Many human, animal and plant pathogenic bacteria employ a molecular machine termed injectisome to inject their toxins into host cells. Because injectisomes are crucial for these bacteria’s infectious potential they have been considered as targets for antiinfective drugs. Injectisomes are highly similar between the different bacterial pathogens and most of their overall structure is well established at the molecular level. However, only little information is available for a central part of the injectisome named the translocon. This pore-like assembly integrates into host cell membranes and thereby serves as an entry gate for the bacterial toxins. We used state of the art fluorescence microscopy to watch translocons of the diarrheagenic pathogen Yersinia enterocolitica during infection of human host cells. Thereby we could for the first time—with fluorescence microscopy—visualize translocons connected to other parts of the injectisome. Furthermore, because translocons mark functional injectisomes we could obtain evidence that injectisomes only become active for secretion of translocators when the bacteria are almost completely enclosed by host cells. These findings provide a novel view on the organization and regulation of bacterial translocons and may thus open up new strategies to block the function of infectious bacteria.
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Affiliation(s)
- Theresa Nauth
- Institute of Medical Microbiology, Virology and Hygiene, University Medical Center Hamburg-Eppendorf (UKE), Hamburg, Germany
| | - Franziska Huschka
- Institute of Medical Microbiology, Virology and Hygiene, University Medical Center Hamburg-Eppendorf (UKE), Hamburg, Germany
| | - Michaela Schweizer
- Center for Molecular Neurobiology (ZMNH), University Medical Center Hamburg-Eppendorf (UKE), Hamburg, Germany
| | - Jens B. Bosse
- Heinrich-Pette-Institute (HPI), Leibniz-Institute for Experimental Virology, Hamburg, Germany
| | - Andreas Diepold
- Department of Ecophysiology, Max-Planck-Institute for Terrestrial Microbiology, Marburg, Germany
| | - Antonio Virgilio Failla
- UKE Microscopy Imaging Facility, University Medical Center Hamburg-Eppendorf (UKE), Hamburg, Germany
| | - Anika Steffen
- Department of Cell Biology, Helmholtz Centre for Infection Research (HZI), Braunschweig, Germany
| | - Theresia E. B. Stradal
- Department of Cell Biology, Helmholtz Centre for Infection Research (HZI), Braunschweig, Germany
| | - Manuel Wolters
- Institute of Medical Microbiology, Virology and Hygiene, University Medical Center Hamburg-Eppendorf (UKE), Hamburg, Germany
| | - Martin Aepfelbacher
- Institute of Medical Microbiology, Virology and Hygiene, University Medical Center Hamburg-Eppendorf (UKE), Hamburg, Germany
- * E-mail:
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Jamilloux Y, Magnotti F, Belot A, Henry T. The pyrin inflammasome: from sensing RhoA GTPases-inhibiting toxins to triggering autoinflammatory syndromes. Pathog Dis 2018; 76:4956042. [PMID: 29718184 DOI: 10.1093/femspd/fty020] [Citation(s) in RCA: 34] [Impact Index Per Article: 5.7] [Reference Citation Analysis] [Abstract] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/27/2017] [Accepted: 03/02/2018] [Indexed: 02/07/2023] Open
Abstract
Numerous pathogens including Clostridium difficile and Yersinia pestis have evolved toxins or effectors targeting GTPases from the RhoA subfamily (RhoA/B/C) to inhibit or hijack the host cytoskeleton dynamics. The resulting impairment of RhoA GTPases activity is sensed by the host via an innate immune complex termed the pyrin inflammasome in which caspase-1 is activated. The cascade leading to activation of the pyrin inflammasome has been recently uncovered. In this review, following a brief presentation of RhoA GTPases-modulating toxins, we present the pyrin inflammasome and its regulatory mechanisms. Furthermore, we discuss how some pathogens have developed strategies to escape detection by the pyrin inflammasome. Finally, we present five monogenic autoinflammatory diseases associated with pyrin inflammasome deregulation. The molecular insights provided by the study of these diseases and the corresponding mutations on pyrin inflammasome regulation and activation are presented.
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Affiliation(s)
- Yvan Jamilloux
- Centre International de Recherche en Infectiologie (CIRI), Inserm U1111, Université Claude Bernard Lyon 1, CNRS, UMR5308, Ecole Normale Supérieure de Lyon, F-69007 Lyon, France.,Departement de Médecine Interne, Hopital de la Croix-Rousse, Université Claude Bernard Lyon 1, F-69004 Lyon, France
| | - Flora Magnotti
- Centre International de Recherche en Infectiologie (CIRI), Inserm U1111, Université Claude Bernard Lyon 1, CNRS, UMR5308, Ecole Normale Supérieure de Lyon, F-69007 Lyon, France
| | - Alexandre Belot
- Centre International de Recherche en Infectiologie (CIRI), Inserm U1111, Université Claude Bernard Lyon 1, CNRS, UMR5308, Ecole Normale Supérieure de Lyon, F-69007 Lyon, France.,Service de Néphrologie, Rhumatologie, Dermatologie pédiatrique, Hôpital Femme Mère Enfant, Hospices Civils de Lyon, F-69677 Lyon, France
| | - Thomas Henry
- Centre International de Recherche en Infectiologie (CIRI), Inserm U1111, Université Claude Bernard Lyon 1, CNRS, UMR5308, Ecole Normale Supérieure de Lyon, F-69007 Lyon, France
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YopN Is Required for Efficient Effector Translocation and Virulence in Yersinia pseudotuberculosis. Infect Immun 2018; 86:IAI.00957-17. [PMID: 29760214 DOI: 10.1128/iai.00957-17] [Citation(s) in RCA: 6] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/23/2018] [Accepted: 05/05/2018] [Indexed: 11/20/2022] Open
Abstract
Type III secretion systems (T3SSs) are used by various Gram-negative pathogens to subvert the host defense by a host cell contact-dependent mechanism to secrete and translocate virulence effectors. While the effectors differ between pathogens and determine the pathogenic life style, the overall mechanism of secretion and translocation is conserved. T3SSs are regulated at multiple levels, and some secreted substrates have also been shown to function in regulation. In Yersinia, one of the substrates, YopN, has long been known to function in the host cell contact-dependent regulation of the T3SS. Prior to contact, through its interaction with TyeA, YopN blocks secretion. Upon cell contact, TyeA dissociates from YopN, which is secreted by the T3SS, resulting in the induction of the system. YopN has also been shown to be translocated into target cells by a T3SS-dependent mechanism. However, no intracellular function has yet been assigned to YopN. The regulatory role of YopN involves the N-terminal and C-terminal parts, while less is known about the role of the central region of YopN. Here, we constructed different in-frame deletion mutants within the central region. The deletion of amino acids 76 to 181 resulted in an unaltered regulation of Yop expression and secretion but triggered reduced YopE and YopH translocation within the first 30 min after infection. As a consequence, this deletion mutant lost its ability to block phagocytosis by macrophages. In conclusion, we were able to differentiate the function of YopN in translocation and virulence from its function in regulation.
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35
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CCR2 + Inflammatory Monocytes Are Recruited to Yersinia pseudotuberculosis Pyogranulomas and Dictate Adaptive Responses at the Expense of Innate Immunity during Oral Infection. Infect Immun 2018; 86:IAI.00782-17. [PMID: 29263104 DOI: 10.1128/iai.00782-17] [Citation(s) in RCA: 22] [Impact Index Per Article: 3.7] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/06/2017] [Accepted: 12/12/2017] [Indexed: 01/30/2023] Open
Abstract
Murine Ly6Chi inflammatory monocytes (IMs) require CCR2 to leave the bone marrow and enter mesenteric lymph nodes (MLNs) and other organs in response to Yersinia pseudotuberculosis infection. We are investigating how IMs, which can differentiate into CD11c+ dendritic cells (DCs), contribute to innate and adaptive immunity to Y. pseudotuberculosis Previously, we obtained evidence that IMs are important for a dominant CD8+ T cell response to the epitope YopE69-77 and host survival using intravenous infections with attenuated Y. pseudotuberculosis Here we challenged CCR2+/+ or CCR2-/- mice orally with wild-type Y. pseudotuberculosis to investigate how IMs contribute to immune responses during intestinal infection. Unexpectedly, CCR2-/- mice did not have reduced survival but retained body weight better and their MLNs cleared Y. pseudotuberculosis faster and with reduced lymphadenopathy compared to controls. Enhanced bacterial clearance in CCR2-/- mice correlated with reduced numbers of IMs in spleens and increased numbers of neutrophils in livers. In situ imaging of MLNs and spleens from CCR2-GFP mice showed that green fluorescent protein-positive (GFP+) IMs accumulated at the periphery of neutrophil-rich Yersinia-containing pyogranulomas. GFP+ IMs colocalized with CD11c+ cells and YopE69-77-specific CD8+ T cells in MLNs, suggesting that IM-derived DCs prime adaptive responses in Yersinia pyogranulomas. Consistently, CCR2-/- mice had reduced numbers of splenic DCs, YopE69-77-specific CD8+ T cells, CD4+ T cells, and B cells in organs and lower levels of serum antibodies to Y. pseudotuberculosis antigens. Our data suggest that IMs differentiate into DCs in MLN pyogranulomas and direct adaptive responses in T cells at the expense of innate immunity during oral Y. pseudotuberculosis infection.
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Weber MM, Faris R, van Schaik EJ, Samuel JE. Identification and characterization of arginine finger-like motifs, and endosome-lysosome basolateral sorting signals within the Coxiella burnetii type IV secreted effector protein CirA. Microbes Infect 2018; 20:302-307. [PMID: 29331581 PMCID: PMC6021133 DOI: 10.1016/j.micinf.2017.12.013] [Citation(s) in RCA: 5] [Impact Index Per Article: 0.8] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/28/2017] [Revised: 10/17/2017] [Accepted: 12/20/2017] [Indexed: 01/20/2023]
Abstract
Coxiella burnetii is an obligate intracellular pathogen that replicates in an endolysosome-like compartment termed the Coxiella-containing vacuole (CCV). Formation of this unique replicative niche requires delivery of bacterial effector proteins into the host cytosol where they mediate crucial interactions with the host. We previously identified an essential Dot/Icm effector, CirA that is required for intracellular replication and CCV formation. Furthermore, CirA was shown to stimulate the GTPase activity of RhoA in vitro. In the current study, we used a bioinformatics-guided approach and identified three arginine finger-like motifs, often found in Rho GTPase-activating proteins (GAPs) and endosome-lysosome basolateral sorting signals associated with vesicle trafficking. When expressed in mammalian cells, mutation of either endosome-lysosome-basolateral sorting signals or the arginine finger-like motifs rescued stress phenotypes and decreased plasma membrane localization of ectopically expressed CirA. We further demonstrate that endosome-lysosome sorting signals are required for co-localization with Rab5 and Rab7. Collectively our data indicate that arginine finger-like motifs and endosome-lysosome-basolateral sorting signals within CirA are essential for interaction with the host cytoskeleton.
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Affiliation(s)
- Mary M Weber
- Department of Microbial Pathogenesis and Immunology, Texas A&M Health Science Center, College of Medicine, Bryan, TX, 77807, USA
| | - Robert Faris
- Department of Microbial Pathogenesis and Immunology, Texas A&M Health Science Center, College of Medicine, Bryan, TX, 77807, USA
| | - Erin J van Schaik
- Department of Microbial Pathogenesis and Immunology, Texas A&M Health Science Center, College of Medicine, Bryan, TX, 77807, USA
| | - James E Samuel
- Department of Microbial Pathogenesis and Immunology, Texas A&M Health Science Center, College of Medicine, Bryan, TX, 77807, USA.
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37
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Kim J, Fukuto HS, Brown DA, Bliska JB, London E. Effects of host cell sterol composition upon internalization of Yersinia pseudotuberculosis and clustered β1 integrin. J Biol Chem 2017; 293:1466-1479. [PMID: 29197826 DOI: 10.1074/jbc.m117.811224] [Citation(s) in RCA: 7] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/09/2017] [Revised: 11/29/2017] [Indexed: 11/06/2022] Open
Abstract
Yersinia pseudotuberculosis is a foodborne pathogenic bacterium that causes acute gastrointestinal illness, but its mechanisms of infection are incompletely described. We examined how host cell sterol composition affected Y. pseudotuberculosis uptake. To do this, we depleted or substituted cholesterol in human MDA-MB-231 epithelial cells with various alternative sterols. Decreasing host cell cholesterol significantly reduced pathogen internalization. When host cell cholesterol was substituted with various sterols, only desmosterol and 7-dehydrocholesterol supported internalization. This specificity was not due to sterol dependence of bacterial attachment to host cells, which was similar with all sterols studied. Because a key step in Y. pseudotuberculosis internalization is interaction of the bacterial adhesins invasin and YadA with host cell β1 integrin, we compared the sterol dependence of wildtype Y. pseudotuberculosis internalization with that of Δinv, ΔyadA, and ΔinvΔyadA mutant strains. YadA deletion decreased bacterial adherence to host cells, whereas invasin deletion had no effect. Nevertheless, host cell sterol substitution had a similar effect on internalization of these bacterial deletion strains as on the wildtype bacteria. The ΔinvΔyadA double mutant adhered least to cells and so was not significantly internalized. The sterol structure dependence of Y. pseudotuberculosis internalization differed from that of endocytosis, as monitored using antibody-clustered β1 integrin and previous studies on other proteins, which had a more permissive sterol dependence. This study suggests that agents could be designed to interfere with internalization of Yersinia without disturbing endocytosis.
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Affiliation(s)
- JiHyun Kim
- From the Departments of Biochemistry and Cell Biology and
| | - Hana S Fukuto
- Molecular Genetics and Microbiology and.,Center for Infectious Diseases, Stony Brook University, Stony Brook, New York 11794
| | | | - James B Bliska
- Molecular Genetics and Microbiology and.,Center for Infectious Diseases, Stony Brook University, Stony Brook, New York 11794
| | - Erwin London
- From the Departments of Biochemistry and Cell Biology and
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38
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Guanylate Binding Proteins Regulate Inflammasome Activation in Response to Hyperinjected Yersinia Translocon Components. Infect Immun 2017; 85:IAI.00778-16. [PMID: 28784930 DOI: 10.1128/iai.00778-16] [Citation(s) in RCA: 32] [Impact Index Per Article: 4.6] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/14/2016] [Accepted: 07/31/2017] [Indexed: 01/25/2023] Open
Abstract
Gram-negative bacterial pathogens utilize virulence-associated secretion systems to inject, or translocate, effector proteins into host cells to manipulate cellular processes and promote bacterial replication. However, translocated bacterial products are sensed by nucleotide binding domain and leucine-rich repeat-containing proteins (NLRs), which trigger the formation of a multiprotein complex called the inflammasome, leading to secretion of interleukin-1 (IL-1) family cytokines, pyroptosis, and control of pathogen replication. Pathogenic Yersinia bacteria inject effector proteins termed Yops, as well as pore-forming proteins that comprise the translocon itself, into target cells. The Yersinia translocation regulatory protein YopK promotes bacterial virulence by limiting hyperinjection of the translocon proteins YopD and YopB into cells, thereby limiting cellular detection of Yersinia virulence activity. How hyperinjection of translocon proteins leads to inflammasome activation is currently unknown. We found that translocated YopB and YopD colocalized with the late endosomal/lysosomal protein LAMP1 and that the frequency of YopD and LAMP1 association correlated with the level of caspase-1 activation in individual cells. We also observed colocalization between YopD and Galectin-3, an indicator of endosomal membrane damage. Intriguingly, YopK limited the colocalization of Galectin-3 with YopD, suggesting that YopK limits the induction or sensing of endosomal membrane damage by components of the type III secretion system (T3SS) translocon. Furthermore, guanylate binding proteins (GBPs) encoded on chromosome 3 (GbpChr3 ), which respond to pathogen-induced damage or alteration of host membranes, were necessary for inflammasome activation in response to hyperinjected YopB/-D. Our findings indicate that lysosomal damage by Yersinia translocon proteins promotes inflammasome activation and implicate GBPs as key regulators of this process.
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Synthetic Cyclic Peptomers as Type III Secretion System Inhibitors. Antimicrob Agents Chemother 2017; 61:AAC.00060-17. [PMID: 28652236 DOI: 10.1128/aac.00060-17] [Citation(s) in RCA: 14] [Impact Index Per Article: 2.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/13/2017] [Accepted: 06/10/2017] [Indexed: 12/12/2022] Open
Abstract
Antibiotic-resistant bacteria are an emerging threat to global public health. New classes of antibiotics and tools for antimicrobial discovery are urgently needed. Type III secretion systems (T3SS), which are required by dozens of Gram-negative bacteria for virulence but largely absent from nonpathogenic bacteria, are promising virulence blocker targets. The ability of mammalian cells to recognize the presence of a functional T3SS and trigger NF-κB activation provides a rapid and sensitive method for identifying chemical inhibitors of T3SS activity. In this study, we generated a HEK293 stable cell line expressing green fluorescent protein (GFP) driven by a promoter containing NF-κB enhancer elements to serve as a readout of T3SS function. We identified a family of synthetic cyclic peptide-peptoid hybrid molecules (peptomers) that exhibited dose-dependent inhibition of T3SS effector secretion in Yersinia pseudotuberculosis and Pseudomonas aeruginosa without affecting bacterial growth or motility. Among these inhibitors, EpD-3'N, EpD-1,2N, EpD-1,3'N, EpD-1,2,3'N, and EpD-1,2,4'N exhibited strong inhibitory effects on translocation of the Yersinia YopM effector protein into mammalian cells (>40% translocation inhibition at 7.5 μM) and showed no toxicity to mammalian cells at 240 μM. In addition, EpD-3'N and EpD-1,2,4'N reduced the rounding of HeLa cells caused by the activity of Yersinia effector proteins that target the actin cytoskeleton. In summary, we have discovered a family of novel cyclic peptomers that inhibit the injectisome T3SS but not the flagellar T3SS.
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Endogenous viruses of parasitic wasps: variations on a common theme. Curr Opin Virol 2017; 25:41-48. [DOI: 10.1016/j.coviro.2017.07.002] [Citation(s) in RCA: 52] [Impact Index Per Article: 7.4] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/13/2017] [Revised: 05/29/2017] [Accepted: 07/02/2017] [Indexed: 11/18/2022]
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Lin YH, Machner MP. Exploitation of the host cell ubiquitin machinery by microbial effector proteins. J Cell Sci 2017; 130:1985-1996. [PMID: 28476939 PMCID: PMC5482977 DOI: 10.1242/jcs.188482] [Citation(s) in RCA: 46] [Impact Index Per Article: 6.6] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/19/2022] Open
Abstract
Pathogenic bacteria are in a constant battle for survival with their host. In order to gain a competitive edge, they employ a variety of sophisticated strategies that allow them to modify conserved host cell processes in ways that favor bacterial survival and growth. Ubiquitylation, the covalent attachment of the small modifier ubiquitin to target proteins, is such a pathway. Ubiquitylation profoundly alters the fate of a myriad of cellular proteins by inducing changes in their stability or function, subcellular localization or interaction with other proteins. Given the importance of ubiquitylation in cell development, protein homeostasis and innate immunity, it is not surprising that this post-translational modification is exploited by a variety of effector proteins from microbial pathogens. Here, we highlight recent advances in our understanding of the many ways microbes take advantage of host ubiquitylation, along with some surprising deviations from the canonical theme. The lessons learned from the in-depth analyses of these host-pathogen interactions provide a fresh perspective on an ancient post-translational modification that we thought was well understood.This article is part of a Minifocus on Ubiquitin Regulation and Function. For further reading, please see related articles: 'Mechanisms of regulation and diversification of deubiquitylating enzyme function' by Pawel Leznicki and Yogesh Kulathu (J. Cell Sci.130, 1997-2006). 'Cell scientist to watch - Mads Gyrd-Hansen' (J. Cell Sci.130, 1981-1983).
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Affiliation(s)
- Yi-Han Lin
- Division of Molecular and Cellular Biology, Eunice Kennedy Shriver National Institute of Child Health and Human Development, National Institutes of Health, Bethesda, MD 20892, USA
| | - Matthias P Machner
- Division of Molecular and Cellular Biology, Eunice Kennedy Shriver National Institute of Child Health and Human Development, National Institutes of Health, Bethesda, MD 20892, USA
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Mao C, Gu J, Wang HG, Fang Y, Yang P, Tang B, Li N, Wang TT, Zou QM, Li Q. Translocation of enterohemorrhagic Escherichia coli effector Tir to the plasma membrane via host Golgi apparatus. Mol Med Rep 2017. [PMID: 28627613 DOI: 10.3892/mmr.2017.6763] [Citation(s) in RCA: 5] [Impact Index Per Article: 0.7] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/06/2022] Open
Abstract
The translocated intimin receptor (Tir) is a canonical type III secretion system effector, secreted by the enterohemorrhagic Escherichia coli (E. coli). This receptor alters the regular cellular processing of host cells, to promote intracellular bacterial replication and evasion of the host immune system. Tir is translocated and integrated into the host cell plasma membrane, a process required for its pathogenic activity in these cells, however, the underlying mechanisms of how this occurs remain to be elucidated. The present study used immunofluorescence and immunoelectron microscopy to demonstrate that the Tir of enterohemorrhagic E. coli was localized to the plasma membrane and colocalized with the 58K Golgi protein of the host cells. Treatment with brefeldin A destroyed the Golgi structure, inhibited the formation of actin pedestal and blocked the localization of Tir on the host cell plasma membrane. The results of the present study suggested that Tir is translocated to the host plasma membrane in a Golgi‑dependent manner. It may mimic the activities of eukaryotic secretory proteins in order to make use of the Golgi apparatus for transportation and integration into the plasma membrane. These findings reveal a novel trafficking pathway for the translocation of bacterial secretory effectors to their specific subcellular compartments.
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Affiliation(s)
- Chan Mao
- Department of Clinical Microbiology and Immunology, Southwest Hospital and College of Medical Laboratory Science, Third Military Medical University, Chongqing 400038, P.R. China
| | - Jiang Gu
- National Engineering Research Center for Immunobiological Products, Department of Microbiology and Biochemical Pharmacy, College of Pharmacy, Third Military Medical University, Chongqing 400038, P.R. China
| | - Hai-Guang Wang
- Department of Clinical Microbiology and Immunology, Southwest Hospital and College of Medical Laboratory Science, Third Military Medical University, Chongqing 400038, P.R. China
| | - Yao Fang
- Department of Clinical Microbiology and Immunology, Southwest Hospital and College of Medical Laboratory Science, Third Military Medical University, Chongqing 400038, P.R. China
| | - Ping Yang
- Department of Core Facilities of Imaging Facility, Medical College of Zhejiang University, Hangzhou, Zhejiang 310031, P.R. China
| | - Bin Tang
- Department of Clinical Microbiology and Immunology, Southwest Hospital and College of Medical Laboratory Science, Third Military Medical University, Chongqing 400038, P.R. China
| | - Na Li
- Department of Clinical Microbiology and Immunology, Southwest Hospital and College of Medical Laboratory Science, Third Military Medical University, Chongqing 400038, P.R. China
| | - Ting-Ting Wang
- National Engineering Research Center for Immunobiological Products, Department of Microbiology and Biochemical Pharmacy, College of Pharmacy, Third Military Medical University, Chongqing 400038, P.R. China
| | - Quan-Ming Zou
- National Engineering Research Center for Immunobiological Products, Department of Microbiology and Biochemical Pharmacy, College of Pharmacy, Third Military Medical University, Chongqing 400038, P.R. China
| | - Qian Li
- Department of Clinical Microbiology and Immunology, Southwest Hospital and College of Medical Laboratory Science, Third Military Medical University, Chongqing 400038, P.R. China
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Grabowski B, Schmidt MA, Rüter C. Immunomodulatory Yersinia outer proteins (Yops)-useful tools for bacteria and humans alike. Virulence 2017; 8:1124-1147. [PMID: 28296562 DOI: 10.1080/21505594.2017.1303588] [Citation(s) in RCA: 26] [Impact Index Per Article: 3.7] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/20/2022] Open
Abstract
Human-pathogenic Yersinia produce plasmid-encoded Yersinia outer proteins (Yops), which are necessary to down-regulate anti-bacterial responses that constrict bacterial survival in the host. These Yops are effectively translocated directly from the bacterial into the target cell cytosol by the type III secretion system (T3SS). Cell-penetrating peptides (CPPs) in contrast are characterized by their ability to autonomously cross cell membranes and to transport cargo - independent of additional translocation systems. The recent discovery of bacterial cell-penetrating effector proteins (CPEs) - with the prototype being the T3SS effector protein YopM - established a new class of autonomously translocating immunomodulatory proteins. CPEs represent a vast source of potential self-delivering, anti-inflammatory therapeutics. In this review, we give an update on the characteristic features of the plasmid-encoded Yops and, based on recent findings, propose the further development of these proteins for potential therapeutic applications as natural or artificial cell-penetrating forms of Yops might be of value as bacteria-derived biologics.
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Affiliation(s)
- Benjamin Grabowski
- a Institute of Infectiology - Centre for Molecular Biology of Inflammation (ZMBE), University of Münster , Münster , Germany
| | - M Alexander Schmidt
- a Institute of Infectiology - Centre for Molecular Biology of Inflammation (ZMBE), University of Münster , Münster , Germany
| | - Christian Rüter
- a Institute of Infectiology - Centre for Molecular Biology of Inflammation (ZMBE), University of Münster , Münster , Germany
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Galectin-3 directs antimicrobial guanylate binding proteins to vacuoles furnished with bacterial secretion systems. Proc Natl Acad Sci U S A 2017; 114:E1698-E1706. [PMID: 28193861 DOI: 10.1073/pnas.1615771114] [Citation(s) in RCA: 98] [Impact Index Per Article: 14.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/12/2022] Open
Abstract
Many invasive bacteria establish pathogen-containing vacuoles (PVs) as intracellular niches for microbial growth. Immunity to these infections is dependent on the ability of host cells to recognize PVs as targets for host defense. The delivery of several host defense proteins to PVs is controlled by IFN-inducible guanylate binding proteins (GBPs), which themselves dock to PVs through poorly characterized mechanisms. Here, we demonstrate that GBPs detect the presence of bacterial protein secretion systems as "patterns of pathogenesis" associated with PVs. We report that the delivery of GBP2 to Legionella-containing vacuoles is dependent on the bacterial Dot/Icm secretion system, whereas the delivery of GBP2 to Yersinia-containing vacuoles (YCVs) requires hypersecretion of Yersinia translocon proteins. We show that the presence of bacterial secretion systems directs cytosolic carbohydrate-binding protein Galectin-3 to PVs and that the delivery of GBP1 and GBP2 to Legionella-containing vacuoles or YCVs is substantially diminished in Galectin-3-deficient cells. Our results illustrate that insertion of bacterial secretion systems into PV membranes stimulates Galectin-3-dependent recruitment of antimicrobial GBPs to PVs as part of a coordinated host defense program.
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Lee WL, Singaravelu P, Wee S, Xue B, Ang KC, Gunaratne J, Grimes JM, Swaminathan K, Robinson RC. Mechanisms of Yersinia YopO kinase substrate specificity. Sci Rep 2017; 7:39998. [PMID: 28051168 PMCID: PMC5209680 DOI: 10.1038/srep39998] [Citation(s) in RCA: 9] [Impact Index Per Article: 1.3] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/27/2016] [Accepted: 11/30/2016] [Indexed: 02/06/2023] Open
Abstract
Yersinia bacteria cause a range of human diseases, including yersiniosis, Far East scarlet-like fever and the plague. Yersiniae modulate and evade host immune defences through injection of Yersinia outer proteins (Yops) into phagocytic cells. One of the Yops, YopO (also known as YpkA) obstructs phagocytosis through disrupting actin filament regulation processes - inhibiting polymerization-promoting signaling through sequestration of Rac/Rho family GTPases and by using monomeric actin as bait to recruit and phosphorylate host actin-regulating proteins. Here we set out to identify mechanisms of specificity in protein phosphorylation by YopO that would clarify its effects on cytoskeleton disruption. We report the MgADP structure of Yersinia enterocolitica YopO in complex with actin, which reveals its active site architecture. Using a proteome-wide kinase-interacting substrate screening (KISS) method, we identified that YopO phosphorylates a wide range of actin-modulating proteins and located their phosphorylation sites by mass spectrometry. Using artificial substrates we clarified YopO's substrate length requirements and its phosphorylation consensus sequence. These findings provide fresh insight into the mechanism of the YopO kinase and demonstrate that YopO executes a specific strategy targeting actin-modulating proteins, across multiple functionalities, to compete for control of their native phospho-signaling, thus hampering the cytoskeletal processes required for macrophage phagocytosis.
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Affiliation(s)
- Wei Lin Lee
- Institute of Molecular and Cell Biology, A*STAR (Agency for Science, Technology and Research), Singapore
| | - Pavithra Singaravelu
- Institute of Molecular and Cell Biology, A*STAR (Agency for Science, Technology and Research), Singapore
- Department of Biological Sciences, National University of Singapore, Singapore
| | - Sheena Wee
- Institute of Molecular and Cell Biology, A*STAR (Agency for Science, Technology and Research), Singapore
| | - Bo Xue
- Institute of Molecular and Cell Biology, A*STAR (Agency for Science, Technology and Research), Singapore
| | - Khay Chun Ang
- Institute of Molecular and Cell Biology, A*STAR (Agency for Science, Technology and Research), Singapore
| | - Jayantha Gunaratne
- Institute of Molecular and Cell Biology, A*STAR (Agency for Science, Technology and Research), Singapore
- Department of Anatomy, National University of Singapore, Singapore
| | - Jonathan M. Grimes
- Division of Structural Biology, Wellcome Trust Centre for Human Genetics, University of Oxford, UK
- Diamond Light Source Ltd., UK
| | | | - Robert C. Robinson
- Institute of Molecular and Cell Biology, A*STAR (Agency for Science, Technology and Research), Singapore
- Department of Biochemistry, National University of Singapore, Singapore
- NTU Institute of Structural Biology, Nanyang Technological University, 59 Nanyang Drive, 636921, Singapore
- School of Biological Sciences, Nanyang Technological University, 60 Nanyang Drive, 637551, Singapore
- Lee Kong Chan School of Medicine, 50 Nanyang Avenue, 639798, Singapore
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Francis MS, Amer AAA, Milton DL, Costa TRD. Site-Directed Mutagenesis and Its Application in Studying the Interactions of T3S Components. Methods Mol Biol 2017; 1531:11-31. [PMID: 27837478 DOI: 10.1007/978-1-4939-6649-3_2] [Citation(s) in RCA: 9] [Impact Index Per Article: 1.3] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 06/06/2023]
Abstract
Type III secretion systems are a prolific virulence determinant among Gram-negative bacteria. They are used to paralyze the host cell, which enables bacterial pathogens to establish often fatal infections-unless an effective therapeutic intervention is available. However, as a result of a catastrophic rise in infectious bacteria resistant to conventional antibiotics, these bacteria are again a leading cause of worldwide mortality. Hence, this report describes a pDM4-based site-directed mutagenesis strategy that is assisting in our foremost objective to better understand the fundamental workings of the T3SS, using Yersinia as a model pathogenic bacterium. Examples are given that clearly document how pDM4-mediated site-directed mutagenesis has been used to establish clean point mutations and in-frame deletion mutations that have been instrumental in identifying and understanding the molecular interactions between components of the Yersinia type III secretion system.
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Affiliation(s)
- Matthew S Francis
- Department of Molecular Biology, Umeå University, 6K och 6L, Sjukhusområdet, Umeå, 901 87, Sweden.
- Umeå Centre for Microbial Research, Umeå University, 6K och 6L, Sjukhusområdet, Umeå, 901 87, Sweden.
| | - Ayad A A Amer
- Department of Molecular Biology, Umeå University, 6K och 6L, Sjukhusområdet, Umeå, 901 87, Sweden
- Umeå Centre for Microbial Research, Umeå University, 6K och 6L, Sjukhusområdet, Umeå, 901 87, Sweden
- Helmholtz Centre for Infection Research, Braunschweig, Germany
| | - Debra L Milton
- Department of Molecular Biology, Umeå University, 6K och 6L, Sjukhusområdet, Umeå, 901 87, Sweden
- Umeå Centre for Microbial Research, Umeå University, 6K och 6L, Sjukhusområdet, Umeå, 901 87, Sweden
- Department of Biological and Environmental Sciences, Troy University, Troy, AL, USA
| | - Tiago R D Costa
- Department of Molecular Biology, Umeå University, 6K och 6L, Sjukhusområdet, Umeå, 901 87, Sweden
- Umeå Centre for Microbial Research, Umeå University, 6K och 6L, Sjukhusområdet, Umeå, 901 87, Sweden
- Institute of Structural and Molecular Biology, University College London and Birkbeck, Malet Street, London, UK
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Ratner D, Orning MPA, Proulx MK, Wang D, Gavrilin MA, Wewers MD, Alnemri ES, Johnson PF, Lee B, Mecsas J, Kayagaki N, Goguen JD, Lien E. The Yersinia pestis Effector YopM Inhibits Pyrin Inflammasome Activation. PLoS Pathog 2016; 12:e1006035. [PMID: 27911947 PMCID: PMC5135138 DOI: 10.1371/journal.ppat.1006035] [Citation(s) in RCA: 78] [Impact Index Per Article: 9.8] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/23/2016] [Accepted: 10/31/2016] [Indexed: 12/25/2022] Open
Abstract
Type III secretion systems (T3SS) are central virulence factors for many pathogenic Gram-negative bacteria, and secreted T3SS effectors can block key aspects of host cell signaling. To counter this, innate immune responses can also sense some T3SS components to initiate anti-bacterial mechanisms. The Yersinia pestis T3SS is particularly effective and sophisticated in manipulating the production of pro-inflammatory cytokines IL-1β and IL-18, which are typically processed into their mature forms by active caspase-1 following inflammasome formation. Some effectors, like Y. pestis YopM, may block inflammasome activation. Here we show that YopM prevents Y. pestis induced activation of the Pyrin inflammasome induced by the RhoA-inhibiting effector YopE, which is a GTPase activating protein. YopM blocks YopE-induced Pyrin-mediated caspase-1 dependent IL-1β/IL-18 production and cell death. We also detected YopM in a complex with Pyrin and kinases RSK1 and PKN1, putative negative regulators of Pyrin. In contrast to wild-type mice, Pyrin deficient mice were also highly susceptible to an attenuated Y. pestis strain lacking YopM, emphasizing the importance of inhibition of Pyrin in vivo. A complex interplay between the Y. pestis T3SS and IL-1β/IL-18 production is evident, involving at least four inflammasome pathways. The secreted effector YopJ triggers caspase-8- dependent IL-1β activation, even when YopM is present. Additionally, the presence of the T3SS needle/translocon activates NLRP3 and NLRC4-dependent IL-1β generation, which is blocked by YopK, but not by YopM. Taken together, the data suggest YopM specificity for obstructing the Pyrin pathway, as the effector does not appear to block Y. pestis-induced NLRP3, NLRC4 or caspase-8 dependent caspase-1 processing. Thus, we identify Y. pestis YopM as a microbial inhibitor of the Pyrin inflammasome. The fact that so many of the Y. pestis T3SS components are participating in regulation of IL-1β/IL-18 release suggests that these effects are essential for maximal control of innate immunity during plague. Many pathogenic Gram-negative bacteria express type III secretion systems (T3SS) that translocate bacterial proteins into host cells with the potential of altering normal cell processes. Yersinia pestis, the causative agent of plague, harbors a T3SS which is particularly effective in suppressing innate immunity and release of pro-inflammatory cytokines IL-1β and IL-18, potent triggers of anti-bacterial responses. These cytokines are produced via processing by active caspase-1 in inflammasome complexes. Pyrin is an inflammasome component that recognizes alterations in certain host cell signals. Here we show that the T3SS effector protein YopM inhibits effector YopE-mediated Pyrin-induced caspase-1 activation, IL-1β, IL-18 and cell death triggered by Y. pestis. We also found that blocking the Pyrin pathway is important for disease development in a mouse model of bubonic plague. Thus, YopM is a microbial molecule blocking Pyrin inflammasomes.
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Affiliation(s)
- Dmitry Ratner
- UMass Medical School, Program in Innate Immunity, Division of Infectious Diseases and Immunology, Department of Medicine, Worcester, Massachusetts, United States of America
| | - M. Pontus A. Orning
- UMass Medical School, Program in Innate Immunity, Division of Infectious Diseases and Immunology, Department of Medicine, Worcester, Massachusetts, United States of America
- Centre of Molecular Inflammation Research, Department of Cancer Research and Molecular Medicine, Norwegian University of Science and Technology, Trondheim, Norway
| | - Megan K. Proulx
- UMass Medical School, Department of Microbiology and Physiological Systems, Worcester, Massachusetts, United States of America
| | - Donghai Wang
- UMass Medical School, Program in Innate Immunity, Division of Infectious Diseases and Immunology, Department of Medicine, Worcester, Massachusetts, United States of America
- Department of Medicine, School of Medicine, Duke University, Durham, North Carolina, United States of America
| | - Mikhail A. Gavrilin
- Davis Heart and Lung Research Institute, Division of Pulmonary, Allergy, Critical Care and Sleep Medicine, Department of Internal Medicine, Wexner Medical Center, The Ohio State University, Columbus, Ohio, United States of America
| | - Mark D. Wewers
- Davis Heart and Lung Research Institute, Division of Pulmonary, Allergy, Critical Care and Sleep Medicine, Department of Internal Medicine, Wexner Medical Center, The Ohio State University, Columbus, Ohio, United States of America
| | - Emad S. Alnemri
- Department of Biochemistry and Molecular Biology, Kimmel Cancer Center, Thomas Jefferson University, Philadelphia, Pennsylvania, United States of America
| | - Peter F. Johnson
- Mouse Cancer Genetics Program, Center for Cancer Research, National Cancer Institute, Frederick, Maryland, United States of America
| | - Bettina Lee
- Department of Physiological Chemistry, Genentech, Inc., South San Francisco, California, United States of America
| | - Joan Mecsas
- Department of Molecular Biology and Microbiology, Tufts University School of Medicine, Boston, Massachusetts, United States of America
| | - Nobuhiko Kayagaki
- Department of Physiological Chemistry, Genentech, Inc., South San Francisco, California, United States of America
| | - Jon D. Goguen
- UMass Medical School, Department of Microbiology and Physiological Systems, Worcester, Massachusetts, United States of America
| | - Egil Lien
- UMass Medical School, Program in Innate Immunity, Division of Infectious Diseases and Immunology, Department of Medicine, Worcester, Massachusetts, United States of America
- Centre of Molecular Inflammation Research, Department of Cancer Research and Molecular Medicine, Norwegian University of Science and Technology, Trondheim, Norway
- * E-mail:
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Yersinia pseudotuberculosis Blocks Neutrophil Degranulation. Infect Immun 2016; 84:3369-3378. [PMID: 27620724 DOI: 10.1128/iai.00760-16] [Citation(s) in RCA: 17] [Impact Index Per Article: 2.1] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/02/2016] [Accepted: 09/03/2016] [Indexed: 12/21/2022] Open
Abstract
Neutrophils are essential components of immunity and are rapidly recruited to infected or injured tissue. Upon their activation, neutrophils release granules to the cell's exterior, through a process called degranulation. These granules contain proteins with antimicrobial properties that help combat infection. The enteropathogenic bacterium Yersinia pseudotuberculosis successfully persists as an extracellular bacterium during infection by virtue of its translocation of virulence effectors (Yersinia outer proteins [Yops]) that act in the cytosol of host immune cells to subvert phagocytosis and proinflammatory responses. Here, we investigated the effect of Y. pseudotuberculosis on neutrophil degranulation upon cell contact. We found that virulent Y. pseudotuberculosis was able to prevent secondary granule release. The blocking effect was general, as the release of primary and tertiary granules was also reduced. Degranulation of secondary granules was also blocked in primed neutrophils, suggesting that this mechanism could be an important element of immune evasion. Further, wild-type bacteria conferred a transient block on neutrophils that prevented their degranulation upon contact with plasmid-cured, avirulent Y. pseudotuberculosis and Escherichia coli Detailed analyses showed that the block was strictly dependent on the cooperative actions of the two antiphagocytic effectors, YopE and YopH, suggesting that the neutrophil target structures constituting signaling molecules needed to initiate both phagocytosis and general degranulation. Thus, via these virulence effectors, Yersinia can impair several mechanisms of the neutrophil's antimicrobial arsenal, which underscores the power of its virulence effector machinery.
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Humphreys D, Singh V, Koronakis V. Inhibition of WAVE Regulatory Complex Activation by a Bacterial Virulence Effector Counteracts Pathogen Phagocytosis. Cell Rep 2016; 17:697-707. [PMID: 27732847 PMCID: PMC5081413 DOI: 10.1016/j.celrep.2016.09.039] [Citation(s) in RCA: 23] [Impact Index Per Article: 2.9] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/26/2016] [Revised: 06/24/2016] [Accepted: 09/14/2016] [Indexed: 02/05/2023] Open
Abstract
To establish pathogenicity, bacteria must evade phagocytosis directed by remodeling of the actin cytoskeleton. We show that macrophages facilitate pathogen phagocytosis through actin polymerization mediated by the WAVE regulatory complex (WRC), small GTPases Arf and Rac1, and the Arf1 activator ARNO. To establish extracellular infections, enteropathogenic (EPEC) and enterohaemorrhagic (EHEC) Escherichia coli hijack the actin cytoskeleton by injecting virulence effectors into the host cell. Here, we find that the virulence effector EspG counteracts WRC-dependent phagocytosis, enabling EPEC and EHEC to remain extracellular. By reconstituting membrane-associated actin polymerization, we find that EspG disabled WRC activation through two mechanisms: EspG interaction with Arf6 blocked signaling to ARNO while EspG binding of Arf1 impeded collaboration with Rac1, thereby inhibiting WRC recruitment and activation. Investigating the mode of EspG interference revealed sites in Arf1 required for WRC activation and a mechanism facilitating pathogen evasion of innate host defenses.
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Affiliation(s)
- Daniel Humphreys
- Department of Pathology, University of Cambridge, Tennis Court Road, Cambridge CB2 1QP, UK.
| | - Vikash Singh
- Department of Pathology, University of Cambridge, Tennis Court Road, Cambridge CB2 1QP, UK
| | - Vassilis Koronakis
- Department of Pathology, University of Cambridge, Tennis Court Road, Cambridge CB2 1QP, UK.
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