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Chanson A, Moreau CS, Duplais C. Assessing Biosynthetic Gene Cluster Diversity of Specialized Metabolites in the Conserved Gut Symbionts of Herbivorous Turtle Ants. Front Microbiol 2021; 12:678100. [PMID: 34267736 PMCID: PMC8277422 DOI: 10.3389/fmicb.2021.678100] [Citation(s) in RCA: 4] [Impact Index Per Article: 1.3] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/08/2021] [Accepted: 05/28/2021] [Indexed: 12/24/2022] Open
Abstract
Cephalotes are herbivorous ants (>115 species) feeding on low-nitrogen food sources, and they rely on gut symbionts to supplement their diet by recycling nitrogen food waste into amino acids. These conserved gut symbionts, which encompass five bacterial orders, have been studied previously for their primary nitrogen metabolism; however, little is known about their ability to biosynthesize specialized metabolites which can play a role in bacterial interactions between communities living in close proximity in the gut. To evaluate the biosynthetic potential of their gut symbionts, we mine 14 cultured isolate genomes and gut metagenomes across 17 Cephalotes species to explore the biodiversity of biosynthetic gene clusters (BGCs) producing specialized metabolites. The diversity of BGCs across Cephalotes phylogeny was analyzed using sequence similarity networking and BGC phylogenetic reconstruction. Our results reveal that the conserved gut symbionts involved in the nutritional symbiosis possess 80% of all the 233 BGCs retrieved in this work. Furthermore, the phylogenetic analysis of BGCs reveals different patterns of distribution, suggesting different mechanisms of conservation. A siderophore BGC shows high similarity in a single symbiont across different ant host species, whereas a BGC encoding the production of non-ribosomal peptides (NRPs) found different symbionts within a single host species. Additionally, BGCs were abundant in four of the five bacterial orders of conserved symbionts co-occurring in the hindgut. However, one major symbiont localized alone in the midgut lack BGCs. Because the spatial isolation prevents direct interaction with other symbionts, this result supports the idea that BGCs are maintained in bacteria living in close proximity but are dispensable for an alone-living symbiont. These findings together pave the way for studying the mechanisms of BGC conservation and evolution in gut bacterial genomes associated with Cephalotes. This work also provides a genetic background for further study, aiming to characterize bacterial specialized metabolites and to understand their functional role in multipartite mutualisms between conserved gut symbionts and Cephalotes turtle ants.
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Affiliation(s)
- Anaïs Chanson
- Université de Guyane, UMR 8172 EcoFoG, AgroParisTech, CNRS, Cirad, INRAE, Université des Antilles, Kourou, France
| | - Corrie S. Moreau
- Department of Entomology and Ecology & Evolutionary Biology, Cornell University, Ithaca, NY, United States
| | - Christophe Duplais
- CNRS, UMR 8172 EcoFoG, AgroParisTech, Cirad, INRAE, Université des Antilles, Université de Guyane, Kourou, France
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2
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L Dragan A, E Voth D. Take my breath away: studying pathogen invasion of the human lung using primary tissue models. Pathog Dis 2021; 79:6177680. [PMID: 33734371 DOI: 10.1093/femspd/ftab016] [Citation(s) in RCA: 3] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/29/2021] [Accepted: 03/16/2021] [Indexed: 01/15/2023] Open
Abstract
The human pulmonary environment is complex, containing a matrix of cells, including fibroblasts, epithelial cells, interstitial macrophages, alveolar macrophages and neutrophils. When confronted with foreign material or invading pathogens, these cells mount a robust response. Nevertheless, many bacterial pathogens with an intracellular lifecycle stage exploit this environment for replication and survival. These include, but are not limited to, Coxiella burnetii, Legionella pneumophila, Yersinia pestis, Mycobacterium tuberculosis and Staphylococcus aureus. Currently, few human disease-relevant model systems exist for studying host-pathogen interactions during these bacterial infections in the lung. Here, we present two novel infection platforms, human alveolar macrophages (hAMs) and human precision-cut lung slices (hPCLS), along with an up-to-date synopsis of research using said models. Additionally, alternative uses for these systems in the absence of pathogen involvement are presented, such as tissue banking and further characterization of the human lung environment. Overall, hAMs and hPCLS allow novel human disease-relevant investigations that other models, such as cell lines and animal models, cannot completely provide.
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Affiliation(s)
- Amanda L Dragan
- Department of Microbiology and Immunology, University of Arkansas for Medical Sciences, Little Rock, AR 72205, USA
| | - Daniel E Voth
- Department of Microbiology and Immunology, University of Arkansas for Medical Sciences, Little Rock, AR 72205, USA
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3
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Bozzaro S, Buracco S, Peracino B, Eichinger L. Dictyostelium Host Response to Legionella Infection: Strategies and Assays. Methods Mol Biol 2019; 1921:347-370. [PMID: 30694504 DOI: 10.1007/978-1-4939-9048-1_23] [Citation(s) in RCA: 4] [Impact Index Per Article: 0.8] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/11/2022]
Abstract
The professional phagocyte Dictyostelium discoideum is a well-established model organism to study host-pathogen interactions. Dictyostelium amoebae grow as separate, independent cells; they divide by binary fission and take up bacteria and yeast via phagocytosis. In the year 2000, D. discoideum was described by two groups as a novel system for genetic analysis of host-pathogen interactions for the intracellular pathogen Legionella pneumophila. Since then additional microbial pathogens that can be studied in D. discoideum have been reported. The organism has various advantages for the dissection of the complex cross-talk between a host and a pathogen. A fully sequenced and well-curated genome is available, there are excellent molecular genetic tools on the market, and the generation of targeted multiple gene knock-outs as well as the realization of untargeted genetic screens is generally straightforward. Dictyostelium also offers easy cultivation, and the cells are suitable for cell biological studies, which in combination with in vivo expression of fluorescence-tagged proteins allows the investigation of the dynamics of bacterial uptake and infection. Furthermore, a large mutant collection is available at the Dictyostelium stock center, favoring the identification of host resistance or susceptibility genes. Here, we briefly describe strategies to identify host cell factors important during an infection, followed by protocols for cell culture and storage, uptake and infection, and confocal microscopy of infected cells.
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Affiliation(s)
- Salvatore Bozzaro
- Department of Clinical and Biological Sciences, University of Turin, Orbassano, Italy.
| | - Simona Buracco
- Department of Clinical and Biological Sciences, University of Turin, Orbassano, Italy
| | - Barbara Peracino
- Department of Clinical and Biological Sciences, University of Turin, Orbassano, Italy
| | - Ludwig Eichinger
- Center for Biochemistry, Medical Faculty, University of Cologne, Cologne, Germany.
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4
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Sun S, Noorian P, McDougald D. Dual Role of Mechanisms Involved in Resistance to Predation by Protozoa and Virulence to Humans. Front Microbiol 2018; 9:1017. [PMID: 29867902 PMCID: PMC5967200 DOI: 10.3389/fmicb.2018.01017] [Citation(s) in RCA: 38] [Impact Index Per Article: 6.3] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/14/2018] [Accepted: 04/30/2018] [Indexed: 12/12/2022] Open
Abstract
Most opportunistic pathogens transit in the environment between hosts and the environment plays a significant role in the evolution of protective traits. The coincidental evolution hypothesis suggests that virulence factors arose as a response to other selective pressures rather for virulence per se. This idea is strongly supported by the elucidation of bacterial-protozoal interactions. In response to protozoan predation, bacteria have evolved various defensive mechanisms which may also function as virulence factors. In this review, we summarize the dual role of factors involved in both grazing resistance and human pathogenesis, and compare the traits using model intracellular and extracellular pathogens. Intracellular pathogens rely on active invasion, blocking of the phagosome and lysosome fusion and resistance to phagocytic digestion to successfully invade host cells. In contrast, extracellular pathogens utilize toxin secretion and biofilm formation to avoid internalization by phagocytes. The complexity and diversity of bacterial virulence factors whose evolution is driven by protozoan predation, highlights the importance of protozoa in evolution of opportunistic pathogens.
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Affiliation(s)
- Shuyang Sun
- ithree Institute, University of Technology Sydney, Sydney, NSW, Australia
| | - Parisa Noorian
- ithree Institute, University of Technology Sydney, Sydney, NSW, Australia.,School of Biotechnology and Biomolecular Sciences, The University of New South Wales, Sydney, NSW, Australia
| | - Diane McDougald
- ithree Institute, University of Technology Sydney, Sydney, NSW, Australia.,Singapore Centre for Environmental Life Sciences Engineering, Nanyang Technological University, Singapore, Singapore
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5
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Dhakshinamoorthy R, Bitzhenner M, Cosson P, Soldati T, Leippe M. The Saposin-Like Protein AplD Displays Pore-Forming Activity and Participates in Defense Against Bacterial Infection During a Multicellular Stage of Dictyostelium discoideum. Front Cell Infect Microbiol 2018; 8:73. [PMID: 29662839 PMCID: PMC5890168 DOI: 10.3389/fcimb.2018.00073] [Citation(s) in RCA: 6] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/22/2017] [Accepted: 02/27/2018] [Indexed: 11/15/2022] Open
Abstract
Due to their archaic life style and microbivor behavior, amoebae may represent a source of antimicrobial peptides and proteins. The amoebic protozoon Dictyostelium discoideum has been a model organism in cell biology for decades and has recently also been used for research on host-pathogen interactions and the evolution of innate immunity. In the genome of D. discoideum, genes can be identified that potentially allow the synthesis of a variety of antimicrobial proteins. However, at the protein level only very few antimicrobial proteins have been characterized that may interact directly with bacteria and help in fighting infection of D. discoideum with potential pathogens. Here, we focus on a large group of gene products that structurally belong to the saposin-like protein (SAPLIP) family and which members we named provisionally Apls (amoebapore-like peptides) according to their similarity to a comprehensively studied antimicrobial and cytotoxic pore-forming protein of the protozoan parasite Entamoeba histolytica. We focused on AplD because it is the only Apl gene that is reported to be primarily transcribed further during the multicellular stages such as the mobile slug stage. Upon knock-out (KO) of the gene, aplD− slugs became highly vulnerable to virulent Klebsiella pneumoniae. AplD− slugs harbored bacterial clumps in their interior and were unable to slough off the pathogen in their slime sheath. Re-expression of AplD in aplD− slugs rescued the susceptibility toward K. pneumoniae. The purified recombinant protein rAplD formed pores in liposomes and was also capable of permeabilizing the membrane of live Bacillus megaterium. We propose that the multifarious Apl family of D. discoideum comprises antimicrobial effector polypeptides that are instrumental to interact with bacteria and their phospholipid membranes. The variety of its members would allow a complementary and synergistic action against a variety of microbes, which the amoeba encounters in its environment.
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Affiliation(s)
| | - Moritz Bitzhenner
- Zoological Institute, Comparative Immunobiology, University of Kiel, Kiel, Germany
| | - Pierre Cosson
- Department of Cell Physiology and Metabolism, Faculty of Medicine, University of Geneva, Geneva, Switzerland
| | - Thierry Soldati
- Department of Biochemistry, Faculty of Science, University of Geneva, Geneva, Switzerland
| | - Matthias Leippe
- Zoological Institute, Comparative Immunobiology, University of Kiel, Kiel, Germany
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6
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Swart AL, Harrison CF, Eichinger L, Steinert M, Hilbi H. Acanthamoeba and Dictyostelium as Cellular Models for Legionella Infection. Front Cell Infect Microbiol 2018; 8:61. [PMID: 29552544 PMCID: PMC5840211 DOI: 10.3389/fcimb.2018.00061] [Citation(s) in RCA: 65] [Impact Index Per Article: 10.8] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/23/2017] [Accepted: 02/13/2018] [Indexed: 12/20/2022] Open
Abstract
Environmental bacteria of the genus Legionella naturally parasitize free-living amoebae. Upon inhalation of bacteria-laden aerosols, the opportunistic pathogens grow intracellularly in alveolar macrophages and can cause a life-threatening pneumonia termed Legionnaires' disease. Intracellular replication in amoebae and macrophages takes place in a unique membrane-bound compartment, the Legionella-containing vacuole (LCV). LCV formation requires the bacterial Icm/Dot type IV secretion system, which translocates literally hundreds of "effector" proteins into host cells, where they modulate crucial cellular processes for the pathogen's benefit. The mechanism of LCV formation appears to be evolutionarily conserved, and therefore, amoebae are not only ecologically significant niches for Legionella spp., but also useful cellular models for eukaryotic phagocytes. In particular, Acanthamoeba castellanii and Dictyostelium discoideum emerged over the last years as versatile and powerful models. Using genetic, biochemical and cell biological approaches, molecular interactions between amoebae and Legionella pneumophila have recently been investigated in detail with a focus on the role of phosphoinositide lipids, small and large GTPases, autophagy components and the retromer complex, as well as on bacterial effectors targeting these host factors.
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Affiliation(s)
- A Leoni Swart
- Institute of Medical Microbiology, Medical Faculty, University of Zurich, Zurich, Switzerland
| | - Christopher F Harrison
- Max von Pettenkofer Institute, Medical Faculty, Ludwig-Maximilians University Munich, Munich, Germany
| | - Ludwig Eichinger
- Institute for Biochemistry I, Medical Faculty, University Hospital Cologne, Cologne, Germany
| | - Michael Steinert
- Department of Life Sciences, Institute of Microbiology, Technical University of Braunschweig, Braunschweig, Germany
| | - Hubert Hilbi
- Institute of Medical Microbiology, Medical Faculty, University of Zurich, Zurich, Switzerland
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7
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Tørring T, Shames SR, Cho W, Roy CR, Crawford JM. Acyl Histidines: New N-Acyl Amides from Legionella pneumophila. Chembiochem 2017; 18:638-646. [PMID: 28116768 PMCID: PMC5546091 DOI: 10.1002/cbic.201600618] [Citation(s) in RCA: 9] [Impact Index Per Article: 1.3] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/16/2016] [Indexed: 11/11/2022]
Abstract
Legionella pneumophila, the causative agent of Legionnaires' disease, is a Gram-negative gammaproteobacterial pathogen that infects and intracellularly replicates in human macrophages and a variety of protozoa. L. pneumophila encodes an orphan biosynthetic gene cluster (BGC) that contains isocyanide-associated biosynthetic genes and is upregulated during infection. Because isocyanide-functionalized metabolites are known to harbor invertebrate innate immunosuppressive activities in bacterial pathogen-insect interactions, we used pathway-targeted molecular networking and tetrazine-based chemoseletive ligation chemistry to characterize the metabolites from the orphan pathway in L. pneumophila. We also assessed their intracellular growth contributions in an amoeba and in murine bone-marrow-derived macrophages. Unexpectedly, two distinct groups of aromatic amino acid-derived metabolites were identified from the pathway, including a known tyrosine-derived isocyanide and a family of new N-acyl-l-histidine metabolites.
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Affiliation(s)
- Thomas Tørring
- Interdiscplinary Nanoscience Center, Aarhus University, Gustav Wieds Vej 14, 8000, Aarhus C, Denmark
| | - Stephanie R Shames
- Department of Microbial Pathogenesis, Yale School of Medicine, 333 Cedar Street, New Haven, CT, 06510, USA
| | - Wooyoung Cho
- Department of Chemistry, Yale University, 225 Prospect Street, New Haven, CT, 06511, USA
- Chemical Biology Institute, Yale University, 600 West Campus Drive, West Haven, CT, 06516, USA
| | - Craig R Roy
- Department of Microbial Pathogenesis, Yale School of Medicine, 333 Cedar Street, New Haven, CT, 06510, USA
| | - Jason M Crawford
- Department of Microbial Pathogenesis, Yale School of Medicine, 333 Cedar Street, New Haven, CT, 06510, USA
- Department of Chemistry, Yale University, 225 Prospect Street, New Haven, CT, 06511, USA
- Chemical Biology Institute, Yale University, 600 West Campus Drive, West Haven, CT, 06516, USA
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8
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Hoppe J, Ünal CM, Thiem S, Grimpe L, Goldmann T, Gaßler N, Richter M, Shevchuk O, Steinert M. PilY1 Promotes Legionella pneumophila Infection of Human Lung Tissue Explants and Contributes to Bacterial Adhesion, Host Cell Invasion, and Twitching Motility. Front Cell Infect Microbiol 2017; 7:63. [PMID: 28326293 PMCID: PMC5339237 DOI: 10.3389/fcimb.2017.00063] [Citation(s) in RCA: 26] [Impact Index Per Article: 3.7] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/30/2016] [Accepted: 02/20/2017] [Indexed: 11/13/2022] Open
Abstract
Legionnaires' disease is an acute fibrinopurulent pneumonia. During infection Legionella pneumophila adheres to the alveolar lining and replicates intracellularly within recruited macrophages. Here we provide a sequence and domain composition analysis of the L. pneumophila PilY1 protein, which has a high homology to PilY1 of Pseudomonas aeruginosa. PilY1 proteins of both pathogens contain a von Willebrand factor A (vWFa) and a C-terminal PilY domain. Using cellular fractionation, we assigned the L. pneumophila PilY1 as an outer membrane protein that is only expressed during the transmissive stationary growth phase. PilY1 contributes to infection of human lung tissue explants (HLTEs). A detailed analysis using THP-1 macrophages and A549 lung epithelial cells revealed that this contribution is due to multiple effects depending on host cell type. Deletion of PilY1 resulted in a lower replication rate in THP-1 macrophages but not in A549 cells. Further on, adhesion to THP-1 macrophages and A549 epithelial cells was decreased. Additionally, the invasion into non-phagocytic A549 epithelial cells was drastically reduced when PilY1 was absent. Complementation variants of a PilY1-negative mutant revealed that the C-terminal PilY domain is essential for restoring the wild type phenotype in adhesion, while the putatively mechanosensitive vWFa domain facilitates invasion into non-phagocytic cells. Since PilY1 also promotes twitching motility of L. pneumophila, we discuss the putative contribution of this newly described virulence factor for bacterial dissemination within infected lung tissue.
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Affiliation(s)
- Julia Hoppe
- Institut für Mikrobiologie, Technische Universität Braunschweig Braunschweig, Germany
| | - Can M Ünal
- Institut für Mikrobiologie, Technische Universität Braunschweig Braunschweig, Germany
| | - Stefanie Thiem
- Institut für Mikrobiologie, Technische Universität Braunschweig Braunschweig, Germany
| | - Louisa Grimpe
- Institut für Mikrobiologie, Technische Universität Braunschweig Braunschweig, Germany
| | - Torsten Goldmann
- Pathology of the University Hospital of Lübeck and the Leibniz Research CenterBorstel, Germany; Airway Research Center North (ARCN), Member of the German Center for Lung ResearchBorstel, Germany
| | - Nikolaus Gaßler
- Institut für Pathologie, Klinikum Braunschweig Braunschweig, Germany
| | | | - Olga Shevchuk
- Center for Proteomics, University of Rijeka Rijeka, Croatia
| | - Michael Steinert
- Institut für Mikrobiologie, Technische Universität BraunschweigBraunschweig, Germany; Helmholtz Center for Infection ResearchBraunschweig, Germany
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9
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Tobias NJ, Ahrendt T, Schell U, Miltenberger M, Hilbi H, Bode HB. Legionella shows a diverse secondary metabolism dependent on a broad spectrum Sfp-type phosphopantetheinyl transferase. PeerJ 2016; 4:e2720. [PMID: 27904811 PMCID: PMC5126622 DOI: 10.7717/peerj.2720] [Citation(s) in RCA: 4] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/29/2016] [Accepted: 10/25/2016] [Indexed: 01/01/2023] Open
Abstract
Several members of the genus Legionella cause Legionnaires' disease, a potentially debilitating form of pneumonia. Studies frequently focus on the abundant number of virulence factors present in this genus. However, what is often overlooked is the role of secondary metabolites from Legionella. Following whole genome sequencing, we assembled and annotated the Legionella parisiensis DSM 19216 genome. Together with 14 other members of the Legionella, we performed comparative genomics and analysed the secondary metabolite potential of each strain. We found that Legionella contains a huge variety of biosynthetic gene clusters (BGCs) that are potentially making a significant number of novel natural products with undefined function. Surprisingly, only a single Sfp-like phosphopantetheinyl transferase is found in all Legionella strains analyzed that might be responsible for the activation of all carrier proteins in primary (fatty acid biosynthesis) and secondary metabolism (polyketide and non-ribosomal peptide synthesis). Using conserved active site motifs, we predict some novel compounds that are probably involved in cell-cell communication, differing to known communication systems. We identify several gene clusters, which may represent novel signaling mechanisms and demonstrate the natural product potential of Legionella.
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Affiliation(s)
- Nicholas J. Tobias
- Fachbereich Biowissenschaften, Merck Stiftungsprofessur für Molekulare Biotechnologie, Goethe Universität, Frankfurt am Main, Germany
| | - Tilman Ahrendt
- Fachbereich Biowissenschaften, Merck Stiftungsprofessur für Molekulare Biotechnologie, Goethe Universität, Frankfurt am Main, Germany
| | - Ursula Schell
- Max von Pettenkofer Institute, Ludwig-Maximilians-Universität München, Munich, Germany
| | - Melissa Miltenberger
- Fachbereich Biowissenschaften, Merck Stiftungsprofessur für Molekulare Biotechnologie, Goethe Universität, Frankfurt am Main, Germany
| | - Hubert Hilbi
- Max von Pettenkofer Institute, Ludwig-Maximilians-Universität München, Munich, Germany
- Institute of Medical Microbiology, University of Zürich, Zürich, Switzerland
| | - Helge B. Bode
- Fachbereich Biowissenschaften, Merck Stiftungsprofessur für Molekulare Biotechnologie, Goethe Universität, Frankfurt am Main, Germany
- Buchmann Institute for Molecular Life Sciences, Goethe Universität, Frankfurt am Main, Germany
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10
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Rasch J, Krüger S, Fontvieille D, Ünal CM, Michel R, Labrosse A, Steinert M. Legionella-protozoa-nematode interactions in aquatic biofilms and influence of Mip on Caenorhabditis elegans colonization. Int J Med Microbiol 2016; 306:443-51. [PMID: 27288243 DOI: 10.1016/j.ijmm.2016.05.012] [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: 02/18/2016] [Revised: 05/03/2016] [Accepted: 05/24/2016] [Indexed: 02/08/2023] Open
Abstract
Legionella pneumophila, the causative agent of Legionnaireś disease, is naturally found in aquatic habitats. The intracellular life cycle within protozoa pre-adapted the "accidental" human pathogen to also infect human professional phagocytes like alveolar macrophages. Previous studies employing the model organism Caenorhabditis elegans suggest that also nematodes might serve as a natural host for L. pneumophila. Here, we report for the first time from a natural co-habitation of L. pneumophila and environmental nematode species within biofilms of a warm water spring. In addition, we identified the protozoan species Oxytricha bifaria, Stylonychia mytilus, Ciliophrya sp. which have never been described as potential interaction partners of L. pneumophila before. Modeling and dissection of the Legionella-protozoa-nematode interaction revealed that C. elegans ruptures Legionella-infected amoebal cells and by this means incorporate the pathogen. Further infection studies revealed that the macrophage infectivity potentiator (Mip) protein of L. pneumophila, which is known to bind collagen IV during human lung infection, promotes the colonization of the intestinal tract of L4 larvae of C. elegans and negatively influences the life span of the worms. The Mip-negative L. pneumophila mutant exhibited a 32-fold reduced colonization rate of the nematodes after 48h when compared to the wild-type strain. Taken together, these studies suggest that nematodes may serve as natural hosts for L. pneumophila, promote their persistence and dissemination in the environment, and co-evolutionarily pre-adapt the pathogen for interactions with extracellular constituents of human lung tissue.
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Affiliation(s)
- Janine Rasch
- Institut für Mikrobiologie, Technische Universität Braunschweig, Germany
| | - Stefanie Krüger
- Institut für Mikrobiologie, Technische Universität Braunschweig, Germany
| | | | - Can M Ünal
- Institut für Mikrobiologie, Technische Universität Braunschweig, Germany
| | - Rolf Michel
- Central Institute of the Federal Armed Forces Medical Services, Koblenz, Germany
| | | | - Michael Steinert
- Institut für Mikrobiologie, Technische Universität Braunschweig, Germany; Helmholtz Center for Infection Research, Braunschweig, Germany.
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