1
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do Nascimento Soares T, Silva Valadares V, Cardoso Amorim G, de Mattos Lacerda de Carvalho M, Berrêdo‐Pinho M, Ceneviva Lacerda Almeida F, Mascarello Bisch P, Batista PR, Miranda Santos Lery L. The C‐terminal extension of
VgrG4
from
Klebsiella pneumoniae
remodels host cell microfilaments. Proteins 2022; 90:1655-1668. [PMID: 35430767 PMCID: PMC9542434 DOI: 10.1002/prot.26344] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/08/2021] [Revised: 03/11/2022] [Accepted: 04/07/2022] [Indexed: 12/12/2022]
Abstract
Klebsiella pneumoniae is an opportunistic pathogen, which concerns public health systems worldwide, as multiple antibiotic‐resistant strains are frequent. One of its pathogenicity factors is the Type VI Secretion System (T6SS), a macromolecular complex assembled through the bacterial membranes. T6SS injects effector proteins inside target cells. Such effectors confer competitive advantages or modulate the target cell signaling and metabolism to favor bacterial infection. The VgrG protein is a T6SS core component. It may present a variable C‐terminal domain carrying an additional effector function. Kp52.145 genome encodes three VgrG proteins, one of them with a C‐terminal extension (VgrG4‐CTD). VgrG4‐CTD is 138 amino acids long, does not contain domains of known function, but is conserved in some Klebsiella, and non‐Klebsiella species. To get insights into its function, recombinant VgrG4‐CTD was used in pulldown experiments to capture ligands from macrophages and lung epithelial cells. A total of 254 proteins were identified: most of them are ribosomal proteins. Cytoskeleton‐associated and proteins involved in the phagosome maturation pathway were also identified. We further showed that VgrG4‐CTD binds actin and induces actin remodeling in macrophages. This study presents novel clues on the role of K. pneumoniae T6SS in pathogenesis.
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Affiliation(s)
| | | | | | | | - Marcia Berrêdo‐Pinho
- Laboratório de Microbiologia Celular Instituto Oswaldo Cruz Rio de Janeiro Brazil
| | - Fábio Ceneviva Lacerda Almeida
- Centro Nacional de Ressonância Magnética Nuclear Instituto de Bioquímica Médica, Universidade Federal do Rio de Janeiro Rio de Janeiro Brazil
| | - Paulo Mascarello Bisch
- Laboratório de Física‐Biológica Instituto de Biofísica Carlos Chagas Filho, Universidade Federal do Rio de Janeiro Rio de Janeiro Brazil
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2
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A Quorum Sensing-Regulated Type VI Secretion System Containing Multiple Nonredundant VgrG Proteins Is Required for Interbacterial Competition in Chromobacterium violaceum. Microbiol Spectr 2022; 10:e0157622. [PMID: 35876575 PMCID: PMC9430734 DOI: 10.1128/spectrum.01576-22] [Citation(s) in RCA: 6] [Impact Index Per Article: 3.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/20/2022] Open
Abstract
The environmental pathogenic bacterium Chromobacterium violaceum kills Gram-positive bacteria by delivering violacein packed into outer membrane vesicles, but nothing is known about its contact-dependent competition mechanisms. In this work, we demonstrate that C. violaceum utilizes a type VI secretion system (T6SS) containing multiple VgrG proteins primarily for interbacterial competition. The single T6SS of C. violaceum contains six vgrG genes, which are located in the main T6SS cluster and four vgrG islands. Using T6SS core component-null mutant strains, Western blotting, fluorescence microscopy, and competition assays, we showed that the C. violaceum T6SS is active and required for competition against Gram-negative bacteria such as Pseudomonas aeruginosa but dispensable for C. violaceum infection in mice. Characterization of single and multiple vgrG mutants revealed that, despite having high sequence similarity, the six VgrGs show little functional redundancy, with VgrG3 showing a major role in T6SS function. Our coimmunoprecipitation data support a model of VgrG3 interacting directly with the other VgrGs. Moreover, we determined that the promoter activities of T6SS genes increased at high cell density, but the produced Hcp protein was not secreted under such condition. This T6SS growth phase-dependent regulation was dependent on CviR but not on CviI, the components of a C. violaceum quorum sensing (QS) system. Indeed, a ΔcviR but not a ΔcviI mutant was completely defective in Hcp secretion, T6SS activity, and interbacterial competition. Overall, our data reveal that C. violaceum relies on a QS-regulated T6SS to outcompete other bacteria and expand our knowledge about the redundancy of multiple VgrGs. IMPORTANCE The type VI secretion system (T6SS) is a contractile nanomachine used by many Gram-negative bacteria to inject toxic effectors into adjacent cells. The delivered effectors are bound to the components of a puncturing apparatus containing the protein VgrG. The T6SS has been implicated in pathogenesis and, more commonly, in competition among bacteria. Chromobacterium violaceum is an environmental bacterium that causes deadly infections in humans. In this work, we characterized the single T6SS of C. violaceum ATCC 12472, including its six VgrG proteins, regarding its function and regulation. This previously undescribed C. violaceum T6SS is active, regulated by QS, and required for interbacterial competition instead of acute infection in mice. Among the VgrGs, VgrG3, encoded outside the main T6SS cluster, showed a major contribution to T6SS function. These results shed light on a key contact-dependent killing mechanism used by C. violaceum to antagonize other bacteria.
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3
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Le Goff M, Vastel M, Lebrun R, Mansuelle P, Diarra A, Grandjean T, Triponney P, Imbert G, Gosset P, Dessein R, Garnier F, Durand E. Characterization of the Achromobacter xylosoxidans Type VI Secretion System and Its Implication in Cystic Fibrosis. Front Cell Infect Microbiol 2022; 12:859181. [PMID: 35782124 PMCID: PMC9245596 DOI: 10.3389/fcimb.2022.859181] [Citation(s) in RCA: 3] [Impact Index Per Article: 1.5] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/21/2022] [Accepted: 05/10/2022] [Indexed: 11/13/2022] Open
Abstract
Bacteria of the genus Achromobacter are environmental germs, with an unknown reservoir. It can become opportunistic pathogens in immunocompromised patients, causing bacteremia, meningitis, pneumonia, or peritonitis. In recent years, Achromobacter xylosoxidans has emerged with increasing incidence in patients with cystic fibrosis (CF). Recent studies showed that A. xylosoxidans is involved in the degradation of the respiratory function of patients with CF. The respiratory ecosystem of patients with CF is colonized by bacterial species that constantly fight for space and access to nutrients. The type VI secretion system (T6SS) empowers this constant bacterial antagonism, and it is used as a virulence factor in several pathogenic bacteria. This study aimed to investigate the prevalence of the T6SS genes in A. xylosoxidans isolated in patients with CF. We also evaluated clinical and molecular characteristics of T6SS-positive A. xylosoxidans strains. We showed that A. xylosoxidans possesses a T6SS gene cluster and that some environmental and clinical isolates assemble a functional T6SS nanomachine. A. xylosoxidans T6SS is used to target competing bacteria, including other CF-specific pathogens. Finally, we demonstrated the importance of the T6SS in the internalization of A. xylosoxidans in lung epithelial cells and that the T6SS protein Hcp is detected in the sputum of patients with CF. Altogether, these results suggest for the first time a role of T6SS in CF-lung colonization by A. xylosoxidans and opens promising perspective to target this virulence determinant as innovative theranostic options for CF management.
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Affiliation(s)
- Mélanie Le Goff
- Laboratoire d’Ingénierie des Systèmes Macromoléculaires (LISM), Institut de Microbiologie, Bioénergies et Biotechnologie (IM2B), Aix-Marseille Université - Centre National de la Recherche Scientifique (CNRS), Unité Mixte de Recherche (UMR) 7255, Marseille, France
| | - Manon Vastel
- Université de Limoges, INSERM, Centre Hospitalier Universitaire (CHU) Limoges, Unité Mixte de Recherche (UMR) 1092, Limoges, France
| | - Régine Lebrun
- Plateforme Protéomique de l’Institut de Microbiologie de la Méditerranée, Marseille Protéomique, Aix Marseille Université, Centre National de la Recherche Scientifique (CNRS) FR 3479, Marseille, France
| | - Pascal Mansuelle
- Plateforme Protéomique de l’Institut de Microbiologie de la Méditerranée, Marseille Protéomique, Aix Marseille Université, Centre National de la Recherche Scientifique (CNRS) FR 3479, Marseille, France
| | - Ava Diarra
- Université de Lille, Centre National de la Recherche Scientifique (CNRS), INSERM, Centre Hospitalier Universitaire (CHU) Lille, Institut Pasteur de Lille, U1019-Unité Mixte de Recherche (UMR) 9017-CIIL-Centre d’Infection et d’Immunité de Lille, University of Lille, Lille, France
| | - Teddy Grandjean
- Université de Lille, Centre National de la Recherche Scientifique (CNRS), INSERM, Centre Hospitalier Universitaire (CHU) Lille, Institut Pasteur de Lille, U1019-Unité Mixte de Recherche (UMR) 9017-CIIL-Centre d’Infection et d’Immunité de Lille, University of Lille, Lille, France
| | - Pauline Triponney
- Centre National de Référence de la Résistance aux Antibiotiques , Centre Hospitalier Universitaire de Besançon, Besançon, France
| | | | - Philippe Gosset
- Université de Lille, Centre National de la Recherche Scientifique (CNRS), INSERM, Centre Hospitalier Universitaire (CHU) Lille, Institut Pasteur de Lille, U1019-Unité Mixte de Recherche (UMR) 9017-CIIL-Centre d’Infection et d’Immunité de Lille, University of Lille, Lille, France
| | - Rodrigue Dessein
- Université de Lille, Centre National de la Recherche Scientifique (CNRS), INSERM, Centre Hospitalier Universitaire (CHU) Lille, Institut Pasteur de Lille, U1019-Unité Mixte de Recherche (UMR) 9017-CIIL-Centre d’Infection et d’Immunité de Lille, University of Lille, Lille, France
| | - Fabien Garnier
- Université de Limoges, INSERM, Centre Hospitalier Universitaire (CHU) Limoges, Unité Mixte de Recherche (UMR) 1092, Limoges, France
- *Correspondence: Eric Durand, ; ; Fabien Garnier,
| | - Eric Durand
- Laboratoire d’Ingénierie des Systèmes Macromoléculaires (LISM), Institut de Microbiologie, Bioénergies et Biotechnologie (IM2B), Aix-Marseille Université - Centre National de la Recherche Scientifique (CNRS), Unité Mixte de Recherche (UMR) 7255, Marseille, France
- Laboratoire d’Ingénierie des Systèmes Macromoléculaires (LISM), Institut de Microbiologie, Bioénergies et Biotechnologie (IM2B), Aix-Marseille Université - Unité Mixte de Recherche (UMR) 7255, INSERM, Marseille, France
- *Correspondence: Eric Durand, ; ; Fabien Garnier,
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4
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Pazoki M, Darvish Alipour Astaneh S, Ramezanalizadeh F, Jahangiri A, Rasooli I. Immunoprotectivity of Valine-glycine repeat protein G, a potent mediator of pathogenicity, against Acinetobacter baumannii. Mol Immunol 2021; 135:276-284. [PMID: 33940514 DOI: 10.1016/j.molimm.2021.04.026] [Citation(s) in RCA: 5] [Impact Index Per Article: 1.7] [Reference Citation Analysis] [Abstract] [Key Words] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/03/2020] [Revised: 03/19/2021] [Accepted: 04/26/2021] [Indexed: 10/21/2022]
Abstract
Type VI Secretion System (T6SS) contributes to both virulence and antimicrobial resistance in Acinetobacter baumannii. Valine-glycine repeat protein G (VgrG) is the core component of T6SS that exists in many bacterial pathogens that have emerged as a potent mediator of pathogenicity in A. baumannii. Two conserved sequences of vgrG 1263-2295 and vgrG1263-1608 were identified antigenic in various strains of Acinetobacter baumannii. The vgrg1263-1608 sequence was implanted in the Loopless C lobe (LCL) from N. meningitidis for surface display and exposure to functional epitopes. The VgrG and LCL-VgrG were expressed and purified. Groups of BALB/c mice were immunized with these proteins and challenged with A. baumannii. Specific IgG titers, whole-cell ELISA, animal survival rates in active and passive immunizations, the bacterial burden in mice tissues, and cytotoxicity of the proteins were determined. The specific IgG suppressed bacterial burdens in the organs, and increased survival rates were noted in the immunized mice. LCL-VgrG immunization provided better protection against A. baumannii infection than the VgrG immunization. The conserved region of VgrG is probably a safe immunogen to effective vaccine development or an antiserum to control A. baumannii infections.
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Affiliation(s)
| | - Shakiba Darvish Alipour Astaneh
- Department of Biotechnology, Semnan University, Central Administration of Semnan University, Campus 1, P.O. Box 35131 -19111, I. R. of Iran Semnan, Semnan, Iran
| | | | - Abolfazl Jahangiri
- Applied Microbiology Research Center, Systems Biology and Poisonings Institute, Baqiyatallah University of Medical Sciences, Tehran, Iran
| | - Iraj Rasooli
- Department of Biology, Shahed University, Tehran, Iran; Molecular Microbiology Research Center and Department of Biology, Shahed University, Tehran, Iran.
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5
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Perault AI, Chandler CE, Rasko DA, Ernst RK, Wolfgang MC, Cotter PA. Host Adaptation Predisposes Pseudomonas aeruginosa to Type VI Secretion System-Mediated Predation by the Burkholderia cepacia Complex. Cell Host Microbe 2020; 28:534-547.e3. [PMID: 32755549 PMCID: PMC7554260 DOI: 10.1016/j.chom.2020.06.019] [Citation(s) in RCA: 24] [Impact Index Per Article: 6.0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/10/2020] [Revised: 06/05/2020] [Accepted: 06/24/2020] [Indexed: 12/14/2022]
Abstract
Pseudomonas aeruginosa and Burkholderia cepacia complex (Bcc) species are opportunistic lung pathogens of cystic fibrosis (CF) patients. While P. aeruginosa can initiate long-term infections in younger CF patients, Bcc infections only arise in teenagers and adults. Both P. aeruginosa and Bcc use type VI secretion systems (T6SSs) to mediate interbacterial competition. Here, we show P. aeruginosa isolates from teenage and adult CF patients, but not those from young CF patients, are outcompeted by the epidemic Bcc isolate Burkholderia cenocepacia strain AU1054 in a T6SS-dependent manner. The genomes of susceptible P. aeruginosa isolates harbor T6SS-abrogating mutations, the repair of which, in some cases, rendered the isolates resistant. Moreover, seven of eight Bcc strains outcompeted P. aeruginosa strains isolated from the same patients. Our findings suggest certain mutations that arise as P. aeruginosa adapts to the CF lung abrogate T6SS activity, making P. aeruginosa and its human host susceptible to potentially fatal Bcc superinfection.
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Affiliation(s)
- Andrew I Perault
- Department of Microbiology and Immunology, University of North Carolina at Chapel Hill, Chapel Hill, NC 27599, USA
| | - Courtney E Chandler
- Department of Microbial Pathogenesis, University of Maryland, Baltimore, Baltimore, MD 21201, USA
| | - David A Rasko
- Institute for Genome Sciences, University of Maryland, Baltimore, Baltimore, MD 21201, USA; Department of Microbiology and Immunology, University of Maryland, Baltimore, Baltimore, MD 21201, USA
| | - Robert K Ernst
- Department of Microbial Pathogenesis, University of Maryland, Baltimore, Baltimore, MD 21201, USA
| | - Matthew C Wolfgang
- Department of Microbiology and Immunology, University of North Carolina at Chapel Hill, Chapel Hill, NC 27599, USA; Marsio Lung Institute, University of North Carolina at Chapel Hill, Chapel Hill, NC 27599, USA
| | - Peggy A Cotter
- Department of Microbiology and Immunology, University of North Carolina at Chapel Hill, Chapel Hill, NC 27599, USA.
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6
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Kumru S, Tekedar HC, Blom J, Lawrence ML, Karsi A. Genomic diversity in flavobacterial pathogens of aquatic origin. Microb Pathog 2020; 142:104053. [PMID: 32058022 DOI: 10.1016/j.micpath.2020.104053] [Citation(s) in RCA: 13] [Impact Index Per Article: 3.3] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/04/2019] [Revised: 02/07/2020] [Accepted: 02/07/2020] [Indexed: 12/15/2022]
Abstract
Flavobacterium species are considered important fish pathogens in wild and cultured fish throughout the world. They can cause acute, subacute, and chronic infections, which are mainly characterized by gill damage, skin lesions, and deep necrotic ulcerations. Primarily, three Flavobacterium species, F. branchiophilum, F. columnare, and F. psychrophilum, have been reported to cause substantial losses to freshwater fish. In this study, we evaluated genomes of 86 Flavobacterium species isolated from aquatic hosts (mainly fish) to identify their unique and shared genome features. Our results showed that F. columnare genomes cluster into four different genetic groups. In silico secretion system analysis identified that all genomes carry type I (T1SS) and type IX (T9SS) secretion systems, but the number of type I secretion system genes shows diversity between species. F. branchiophilum, F. araucananum, F. chilense, F. spartansii, and F. tructae genomes have full type VI secretion system (T6SS). F. columnare, F. hydatis, and F. plurextorum carry partial T6SS with some of the T6SS genes missing. F. columnare, F. araucananum, F. chilense, F. spartansii, F. araucananum, F. tructae, Flavobacterium sp., F. crassostreae, F. succinicans, F. hydatis, and F. plurextorum carry most of the type IV secretion system genes (T4SS). F. columnare genetic groups 1 and 2, Flavobacterium sp., and F. crassostreae encode the least number of antibiotic resistance elements. F. hydatis, F. chilense, and F. plurextorum encode the greatest number of antibiotic resistance genes. Additionally, F. spartansii, F. araucananum, and chilense encode the greatest number of virulence genes while Flavobacterium sp. and F. crassostreae encode the least number of virulence genes. In conclusion, comparative genomics of Flavobacterium species of aquatic origin will help our understanding of Flavobacterium pathogenesis.
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Affiliation(s)
- Salih Kumru
- Faculty of Fisheries, Recep Tayyip Erdogan University, Rize, Turkey
| | - Hasan C Tekedar
- Department of Basic Sciences, College of Veterinary Medicine, Mississippi State University, Mississippi State, MS, United States
| | - Jochen Blom
- Bioinformatics and Systems Biology, Justus-Liebig-University Giessen, Giessen, Hesse, Germany
| | - Mark L Lawrence
- Department of Basic Sciences, College of Veterinary Medicine, Mississippi State University, Mississippi State, MS, United States
| | - Attila Karsi
- Department of Basic Sciences, College of Veterinary Medicine, Mississippi State University, Mississippi State, MS, United States.
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7
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Spiewak HL, Shastri S, Zhang L, Schwager S, Eberl L, Vergunst AC, Thomas MS. Burkholderia cenocepacia utilizes a type VI secretion system for bacterial competition. Microbiologyopen 2019; 8:e00774. [PMID: 30628184 PMCID: PMC6612558 DOI: 10.1002/mbo3.774] [Citation(s) in RCA: 19] [Impact Index Per Article: 3.8] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/21/2018] [Revised: 11/07/2018] [Accepted: 11/07/2018] [Indexed: 01/24/2023] Open
Abstract
Burkholderia cenocepacia is an opportunistic bacterial pathogen that poses a significant threat to individuals with cystic fibrosis by provoking a strong inflammatory response within the lung. It possesses a type VI secretion system (T6SS), a secretory apparatus that can perforate the cellular membrane of other bacterial species and/or eukaryotic targets, to deliver an arsenal of effector proteins. The B. cenocepacia T6SS (T6SS-1) has been shown to be implicated in virulence in rats and contributes toward actin rearrangements and inflammasome activation in B. cenocepacia-infected macrophages. Here, we present bioinformatics evidence to suggest that T6SS-1 is the archetype T6SS in the Burkholderia genus. We show that B. cenocepacia T6SS-1 is active under normal laboratory growth conditions and displays antibacterial activity against other Gram-negative bacterial species. Moreover, B. cenocepacia T6SS-1 is not required for virulence in three eukaryotic infection models. Bioinformatics analysis identified several candidate T6SS-dependent effectors that may play a role in the antibacterial activity of B. cenocepacia T6SS-1. We conclude that B. cenocepacia T6SS-1 plays an important role in bacterial competition for this organism, and probably in all Burkholderia species that possess this system, thereby broadening the range of species that utilize the T6SS for this purpose.
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Affiliation(s)
- Helena L. Spiewak
- Department of Infection, Immunity and Cardiovascular Disease, The Medical SchoolThe University of SheffieldSheffieldUK,Present address:
Northern Genetics Service, The Newcastle upon Tyne Hospitals NHS Foundation Trust, Institute of Genetic MedicineInternational Centre for LifeNewcastle upon TyneUK
| | - Sravanthi Shastri
- Department of Infection, Immunity and Cardiovascular Disease, The Medical SchoolThe University of SheffieldSheffieldUK
| | - Lili Zhang
- VBMI, INSERM, Université de MontpellierNîmesFrance,Present address:
Section of Molecular Biology, Division of Biological SciencesUniversity of California, San DiegoLa JollaCalifornia
| | - Stephan Schwager
- Department of Plant and Microbial BiologyUniversity of ZurichZurichSwitzerland,Present address:
Analytical ChemistrySynthes GmbHOberdorf BLSwitzerland
| | - Leo Eberl
- Department of Plant and Microbial BiologyUniversity of ZurichZurichSwitzerland
| | | | - Mark S. Thomas
- Department of Infection, Immunity and Cardiovascular Disease, The Medical SchoolThe University of SheffieldSheffieldUK
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8
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An SQ, Ding YC, Faber F, Hobley L, Sá-Pessoa J. Social behaviour and making attachments: a report from the fifth 'Young Microbiologists Symposium on Microbe Signalling, Organisation and Pathogenesis'. MICROBIOLOGY-SGM 2018; 165:138-145. [PMID: 30520711 DOI: 10.1099/mic.0.000746] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 11/18/2022]
Abstract
The fifth Young Microbiologists Symposium was held in Queen's University Belfast, Northern Ireland, in late August 2018. The symposium, focused on 'Microbe signalling, organization and pathogenesis', attracted 121 microbiologists from 15 countries. The meeting allowed junior scientists to present their work to a broad audience, and was supported by the European Molecular Biology Organization, the Federation of European Microbiological Societies, the Society of Applied Microbiology, the Biochemical Society and the Microbiology Society. Sessions covered recent advances in areas of microbiology including gene regulation and signalling, secretion and transport across membranes, infection and immunity, and antibiotics and resistance mechanisms. In this Meeting Report, we highlight some of the most significant advances and exciting developments communicated during talks and poster presentations.
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Affiliation(s)
- Shi-Qi An
- 1Wellcome-Wolfson Institute for Experimental Medicine, Queen's University Belfast, Belfast, UK.,2Biological Sciences, University of Southampton, Southampton, UK
| | - Yi-Chen Ding
- 3Singapore Centre for Environmental Life Sciences Engineering (SCELSE), Nanyang Technological University, Singapore 637551, Asia
| | - Franziska Faber
- 4Institute of Molecular Infection Biology, University of Würzburg, Würzburg, German
| | - Laura Hobley
- 5School of Biosciences, University of Nottingham, Nottingham, UK
| | - Joana Sá-Pessoa
- 1Wellcome-Wolfson Institute for Experimental Medicine, Queen's University Belfast, Belfast, UK
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9
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Dix SR, Owen HJ, Sun R, Ahmad A, Shastri S, Spiewak HL, Mosby DJ, Harris MJ, Batters SL, Brooker TA, Tzokov SB, Sedelnikova SE, Baker PJ, Bullough PA, Rice DW, Thomas MS. Structural insights into the function of type VI secretion system TssA subunits. Nat Commun 2018; 9:4765. [PMID: 30420757 PMCID: PMC6232143 DOI: 10.1038/s41467-018-07247-1] [Citation(s) in RCA: 33] [Impact Index Per Article: 5.5] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/11/2018] [Accepted: 10/23/2018] [Indexed: 11/22/2022] Open
Abstract
The type VI secretion system (T6SS) is a multi-protein complex that injects bacterial effector proteins into target cells. It is composed of a cell membrane complex anchored to a contractile bacteriophage tail-like apparatus consisting of a sharpened tube that is ejected by the contraction of a sheath against a baseplate. We present structural and biochemical studies on TssA subunits from two different T6SSs that reveal radically different quaternary structures in comparison to the dodecameric E. coli TssA that arise from differences in their C-terminal sequences. Despite this, the different TssAs retain equivalent interactions with other components of the complex and position their highly conserved N-terminal ImpA_N domain at the same radius from the centre of the sheath as a result of their distinct domain architectures, which includes additional spacer domains and highly mobile interdomain linkers. Together, these variations allow these distinct TssAs to perform a similar function in the complex. TssA is an important component of the bacterial type VI secretion system (T6SS). Here, Dix et al. integrate structural, phylogenetic and functional analysis of the TssA subunits, providing new insights into their role in T6SS assembly and function.
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Affiliation(s)
- Samuel R Dix
- Department of Molecular Biology and Biotechnology, Krebs Institute, University of Sheffield, Sheffield, S10 2TN, UK
| | - Hayley J Owen
- Department of Molecular Biology and Biotechnology, Krebs Institute, University of Sheffield, Sheffield, S10 2TN, UK
| | - Ruyue Sun
- Department of Infection, Immunity and Cardiovascular Disease, University of Sheffield Medical School, Beech Hill Road, Sheffield, S10 2RX, UK
| | - Asma Ahmad
- Department of Infection, Immunity and Cardiovascular Disease, University of Sheffield Medical School, Beech Hill Road, Sheffield, S10 2RX, UK
| | - Sravanthi Shastri
- Department of Infection, Immunity and Cardiovascular Disease, University of Sheffield Medical School, Beech Hill Road, Sheffield, S10 2RX, UK
| | - Helena L Spiewak
- Department of Infection, Immunity and Cardiovascular Disease, University of Sheffield Medical School, Beech Hill Road, Sheffield, S10 2RX, UK.,Northern Genetics Service, The Newcastle upon Tyne Hospitals NHS Foundation Trust, Institute of Genetic Medicine, International Centre for Life, Newcastle upon Tyne, NE1 3BZ, UK
| | - Daniel J Mosby
- Department of Infection, Immunity and Cardiovascular Disease, University of Sheffield Medical School, Beech Hill Road, Sheffield, S10 2RX, UK
| | - Matthew J Harris
- Department of Molecular Biology and Biotechnology, Krebs Institute, University of Sheffield, Sheffield, S10 2TN, UK.,Department of Chemistry, King's College London, Britannia House, London, SE1 1DB, UK
| | - Sarah L Batters
- Department of Infection, Immunity and Cardiovascular Disease, University of Sheffield Medical School, Beech Hill Road, Sheffield, S10 2RX, UK
| | - Thomas A Brooker
- Department of Infection, Immunity and Cardiovascular Disease, University of Sheffield Medical School, Beech Hill Road, Sheffield, S10 2RX, UK
| | - Svetomir B Tzokov
- Department of Molecular Biology and Biotechnology, Krebs Institute, University of Sheffield, Sheffield, S10 2TN, UK
| | - Svetlana E Sedelnikova
- Department of Molecular Biology and Biotechnology, Krebs Institute, University of Sheffield, Sheffield, S10 2TN, UK
| | - Patrick J Baker
- Department of Molecular Biology and Biotechnology, Krebs Institute, University of Sheffield, Sheffield, S10 2TN, UK
| | - Per A Bullough
- Department of Molecular Biology and Biotechnology, Krebs Institute, University of Sheffield, Sheffield, S10 2TN, UK
| | - David W Rice
- Department of Molecular Biology and Biotechnology, Krebs Institute, University of Sheffield, Sheffield, S10 2TN, UK.
| | - Mark S Thomas
- Department of Infection, Immunity and Cardiovascular Disease, University of Sheffield Medical School, Beech Hill Road, Sheffield, S10 2RX, UK.
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10
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Wang J, Zhou Z, He F, Ruan Z, Jiang Y, Hua X, Yu Y. The role of the type VI secretion system vgrG gene in the virulence and antimicrobial resistance of Acinetobacter baumannii ATCC 19606. PLoS One 2018; 13:e0192288. [PMID: 29394284 PMCID: PMC5796710 DOI: 10.1371/journal.pone.0192288] [Citation(s) in RCA: 43] [Impact Index Per Article: 7.2] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/03/2017] [Accepted: 01/22/2018] [Indexed: 12/21/2022] Open
Abstract
The Type VI Secretion System (T6SS) is an important virulence system that exists in many bacterial pathogens, and has emerged as a potent mediator of pathogenicity in Acinetobacter baumannii. In this study, we inactivated one of the T6SS components vgrG (valine–glycine repeat G) gene in A. baumannii ATCC 19606 and constructed a complementation strain. BEAS-2b human alveolar epithelial cells was adopted to assess bacterial adhesion, and wild female BALB/c mice were used for in vivo experiments to assess the bacterial killing ability to host. Upon deletion of the vgrG gene, increased antimicrobial resistance to ampicillin/sulbactam, but reduced resistance to chloramphenicol were observed. The vgrG mutant strain showed lower growth rate, reduced eukaryotic cell adherence and impaired lethality in mice. However, the vgrG mutant strain is not implicated in biofilm formation. Our study suggests that the Type VI Secretion System core component VgrG contributes to both virulence and antimicrobial resistance in A. baumannii ATCC 19606.
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Affiliation(s)
- Jianfeng Wang
- Department of Respiratory Diseases, The Affiliated Hospital of Hangzhou Normal University, Hangzhou, Zhejiang, China
| | - Zhihui Zhou
- Department of Infectious Diseases, Sir Run Run Shaw Hospital, School of Medicine, Zhejiang University, Hangzhou, Zhejiang, China
- Key laboratory of microbial technology and bioinformatics of Zhejiang Province, Hangzhou, Zhejiang, China
| | - Fang He
- Department of Infectious Diseases, Sir Run Run Shaw Hospital, School of Medicine, Zhejiang University, Hangzhou, Zhejiang, China
- Key laboratory of microbial technology and bioinformatics of Zhejiang Province, Hangzhou, Zhejiang, China
| | - Zhi Ruan
- Department of Infectious Diseases, Sir Run Run Shaw Hospital, School of Medicine, Zhejiang University, Hangzhou, Zhejiang, China
- Key laboratory of microbial technology and bioinformatics of Zhejiang Province, Hangzhou, Zhejiang, China
| | - Yan Jiang
- Department of Infectious Diseases, Sir Run Run Shaw Hospital, School of Medicine, Zhejiang University, Hangzhou, Zhejiang, China
- Key laboratory of microbial technology and bioinformatics of Zhejiang Province, Hangzhou, Zhejiang, China
| | - Xiaoting Hua
- Department of Infectious Diseases, Sir Run Run Shaw Hospital, School of Medicine, Zhejiang University, Hangzhou, Zhejiang, China
- Key laboratory of microbial technology and bioinformatics of Zhejiang Province, Hangzhou, Zhejiang, China
| | - Yunsong Yu
- Department of Infectious Diseases, Sir Run Run Shaw Hospital, School of Medicine, Zhejiang University, Hangzhou, Zhejiang, China
- Key laboratory of microbial technology and bioinformatics of Zhejiang Province, Hangzhou, Zhejiang, China
- * E-mail:
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11
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Development of an Sce-I mutagenesis system for Burkholderia cepacia complex strains. J Microbiol Methods 2018; 146:16-21. [PMID: 29360487 DOI: 10.1016/j.mimet.2018.01.011] [Citation(s) in RCA: 2] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/22/2017] [Revised: 01/17/2018] [Accepted: 01/18/2018] [Indexed: 11/22/2022]
Abstract
The Burkholderia cepacia complex (Bcc) consists of at least 20 phenotypically similar but genotypically distinct Gram-negative bacteria that are ubiquitous in nature, are capable of promoting plant growth and biodegradation of pollutants, but that also are highly antibiotic resistant and produce damaging effects towards plants, fungi, and humans. To study these genetically recalcitrant bacteria in detail, molecular tools are required that work efficiently with the many strains and species of the Bcc. One mutagenesis strategy that has been used effectively to analyze the genes of Burkholderia cenocepacia is based upon the activity of the Sce-I restriction enzyme. Unfortunately, this system is limited in its applicability to many members of the Bcc. Therefore, we undertook the expansion of this system to create an Sce-I mutagenesis system that could be used with many different species and strains of the Bcc, including members of the B. cenocepacia IIIB Midwest clones. We demonstrated the use of this system by clean-deleting the lipo-oligosaccharide (LOS) inner core biosynthesis gene waaC, to create a B. cenocepacia PC184 strain variant with truncated LOS. This enhanced mutagenesis system can be used to analyze a wide range of Burkholderia and other Gram-negative bacteria.
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12
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The Role of Type VI Secretion System Effectors in Target Cell Lysis and Subsequent Horizontal Gene Transfer. Cell Rep 2017; 21:3927-3940. [DOI: 10.1016/j.celrep.2017.12.020] [Citation(s) in RCA: 74] [Impact Index Per Article: 10.6] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/25/2017] [Revised: 11/22/2017] [Accepted: 12/05/2017] [Indexed: 01/13/2023] Open
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13
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Kumru S, Tekedar HC, Gulsoy N, Waldbieser GC, Lawrence ML, Karsi A. Comparative Analysis of the Flavobacterium columnare Genomovar I and II Genomes. Front Microbiol 2017; 8:1375. [PMID: 28790987 PMCID: PMC5524665 DOI: 10.3389/fmicb.2017.01375] [Citation(s) in RCA: 27] [Impact Index Per Article: 3.9] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/11/2017] [Accepted: 07/06/2017] [Indexed: 11/16/2022] Open
Abstract
Columnaris disease caused by Gram-negative rod Flavobacterium columnare is one of the most common diseases of catfish. F. columnare is also a common problem in other cultured fish species worldwide. F. columnare has three major genomovars; we have sequenced a representative strain from genomovar I (ATCC 49512, which is avirulent in catfish) and genomovar II (94-081, which is highly pathogenic in catfish). Here, we present a comparative analysis of the two genomes. Interestingly, F. columnare ATCC 49512 and 94-081 meet criteria to be considered different species based on the Average Nucleotide Identity (90.71% similar) and DNA–DNA Hybridization (42.6% similar). Genome alignment indicated the two genomes have a large number of rearrangements. However, function-based comparative genomics analysis indicated that the two strains have similar functional capabilities with 2,263 conserved orthologous clusters; strain ATCC 49512 has 290 unique orthologous clusters while strain 94-081 has 391. Both strains carry type I secretion system, type VI secretion system, and type IX secretion system. The two genomes also have similar CRISPR capacities. The F. columnare strain ATCC 49512 genome contains a higher number of insertion sequence families and phage regions, while the F. columnare strain 94-081 genome has more genomic islands and more regulatory gene capacity. Transposon mutagenesis using Tn4351 in pathogenic strain 94-081 yielded six mutants, and experimental infections of fish showed hemolysin and glycine cleavage protein mutants had 15 and 10% mortalities, respectively, while the wild-type strain caused 100% mortalities. Our comparative and mutational analysis yielded important information on classification of genomovars I and II F. columnare as well as potential virulence genes in F. columnare strain 94-081.
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Affiliation(s)
- Salih Kumru
- Department of Basic Sciences, College of Veterinary Medicine, Mississippi State UniversityMississippi State, MS, United States
| | - Hasan C Tekedar
- Department of Basic Sciences, College of Veterinary Medicine, Mississippi State UniversityMississippi State, MS, United States
| | - Nagihan Gulsoy
- Department of Biology, Faculty of Art and Sciences, Marmara UniversityIstanbul, Turkey
| | - Geoffrey C Waldbieser
- Warmwater Aquaculture Research Unit, United States Agricultural Research Service, StonevilleMS, United States
| | - Mark L Lawrence
- Department of Basic Sciences, College of Veterinary Medicine, Mississippi State UniversityMississippi State, MS, United States
| | - Attila Karsi
- Department of Basic Sciences, College of Veterinary Medicine, Mississippi State UniversityMississippi State, MS, United States
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14
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Burkholderia cepacia Complex Regulation of Virulence Gene Expression: A Review. Genes (Basel) 2017; 8:genes8010043. [PMID: 28106859 PMCID: PMC5295037 DOI: 10.3390/genes8010043] [Citation(s) in RCA: 30] [Impact Index Per Article: 4.3] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/07/2016] [Revised: 01/11/2017] [Accepted: 01/12/2017] [Indexed: 12/31/2022] Open
Abstract
Burkholderia cepacia complex (Bcc) bacteria emerged as opportunistic pathogens in cystic fibrosis and immunocompromised patients. Their eradication is very difficult due to the high level of intrinsic resistance to clinically relevant antibiotics. Bcc bacteria have large and complex genomes, composed of two to four replicons, with variable numbers of insertion sequences. The complexity of Bcc genomes confers a high genomic plasticity to these bacteria, allowing their adaptation and survival to diverse habitats, including the human host. In this work, we review results from recent studies using omics approaches to elucidate in vivo adaptive strategies and virulence gene regulation expression of Bcc bacteria when infecting the human host or subject to conditions mimicking the stressful environment of the cystic fibrosis lung.
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15
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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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16
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Ratner D, Orning MPA, Lien E. Bacterial secretion systems and regulation of inflammasome activation. J Leukoc Biol 2016; 101:165-181. [PMID: 27810946 DOI: 10.1189/jlb.4mr0716-330r] [Citation(s) in RCA: 18] [Impact Index Per Article: 2.3] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/26/2016] [Revised: 09/19/2016] [Accepted: 09/20/2016] [Indexed: 01/03/2023] Open
Abstract
Innate immunity is critical for host defenses against pathogens, but many bacteria display complex ways of interacting with innate immune signaling, as they may both activate and evade certain pathways. Gram-negative bacteria can exhibit specialized nanomachine secretion systems for delivery of effector proteins into mammalian cells. Bacterial types III, IV, and VI secretion systems (T3SS, T4SS, and T6SS) are known for their impact on caspase-1-activating inflammasomes, necessary for producing bioactive inflammatory cytokines IL-1β and IL-18, key participants of anti-bacterial responses. Here, we discuss how these secretion systems can mediate triggering and inhibition of inflammasome signaling. We propose that a fine balance between secretion system-mediated activation and inhibition can determine net activation of inflammasome activity and control inflammation, clearance, or spread of the infection.
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Affiliation(s)
- Dmitry Ratner
- Program in Innate Immunity, Division of Infectious Diseases and Immunology, Department of Medicine, University of Massachusetts Medical School, Worcester, Massachusetts, USA; and
| | - M Pontus A Orning
- Program in Innate Immunity, Division of Infectious Diseases and Immunology, Department of Medicine, University of Massachusetts Medical School, Worcester, Massachusetts, USA; and.,Centre of Molecular Inflammation Research, Department of Cancer Research and Molecular Medicine, Norges Teknisk-Naturvitenskapelige Universitet, Trondheim, Norway
| | - Egil Lien
- Program in Innate Immunity, Division of Infectious Diseases and Immunology, Department of Medicine, University of Massachusetts Medical School, Worcester, Massachusetts, USA; and .,Centre of Molecular Inflammation Research, Department of Cancer Research and Molecular Medicine, Norges Teknisk-Naturvitenskapelige Universitet, Trondheim, Norway
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17
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Aubert DF, Xu H, Yang J, Shi X, Gao W, Li L, Bisaro F, Chen S, Valvano MA, Shao F. A Burkholderia Type VI Effector Deamidates Rho GTPases to Activate the Pyrin Inflammasome and Trigger Inflammation. Cell Host Microbe 2016; 19:664-74. [PMID: 27133449 DOI: 10.1016/j.chom.2016.04.004] [Citation(s) in RCA: 118] [Impact Index Per Article: 14.8] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/27/2015] [Revised: 03/17/2016] [Accepted: 03/30/2016] [Indexed: 10/21/2022]
Abstract
Burkholderia cenocepacia is an opportunistic pathogen of the cystic fibrosis lung that elicits a strong inflammatory response. B. cenocepacia employs a type VI secretion system (T6SS) to survive in macrophages by disarming Rho-type GTPases, causing actin cytoskeletal defects. Here, we identified TecA, a non-VgrG T6SS effector responsible for actin disruption. TecA and other bacterial homologs bear a cysteine protease-like catalytic triad, which inactivates Rho GTPases by deamidating a conserved asparagine in the GTPase switch-I region. RhoA deamidation induces caspase-1 inflammasome activation, which is mediated by the familial Mediterranean fever disease protein Pyrin. In mouse infection, the deamidase activity of TecA is necessary and sufficient for B. cenocepacia-triggered lung inflammation and also protects mice from lethal B. cenocepacia infection. Therefore, Burkholderia TecA is a T6SS effector that modifies a eukaryotic target through an asparagine deamidase activity, which in turn elicits host cell death and inflammation through activation of the Pyrin inflammasome.
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Affiliation(s)
- Daniel F Aubert
- Department of Microbiology and Immunology, University of Western Ontario, London N6A 5C1, Canada
| | - Hao Xu
- National Institute of Biological Sciences, Beijing 102206, China
| | - Jieling Yang
- National Institute of Biological Sciences, Beijing 102206, China; National Laboratory of Biomacromolecules, Institute of Biophysics, Chinese Academy of Sciences, Beijing 100101, China
| | - Xuyan Shi
- National Institute of Biological Sciences, Beijing 102206, China
| | - Wenqing Gao
- National Institute of Biological Sciences, Beijing 102206, China
| | - Lin Li
- National Institute of Biological Sciences, Beijing 102206, China
| | - Fabiana Bisaro
- Centre for Infection and Immunity, Queen's University Belfast, Belfast BT9 7AE, UK
| | - She Chen
- National Institute of Biological Sciences, Beijing 102206, China
| | - Miguel A Valvano
- Department of Microbiology and Immunology, University of Western Ontario, London N6A 5C1, Canada; Centre for Infection and Immunity, Queen's University Belfast, Belfast BT9 7AE, UK.
| | - Feng Shao
- National Institute of Biological Sciences, Beijing 102206, China; National Institute of Biological Sciences, Beijing, Collaborative Innovation Center for Cancer Medicine, Beijing 102206, China.
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