1
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Alejandro-Navarreto X, Freitag NE. Revisiting old friends: updates on the role of two-component signaling systems in Listeria monocytogenes survival and pathogenesis. Infect Immun 2024; 92:e0034523. [PMID: 38591895 PMCID: PMC11003226 DOI: 10.1128/iai.00345-23] [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] [Indexed: 04/10/2024] Open
Abstract
Listeria monocytogenes is well recognized for both its broad resistance to stress conditions and its ability to transition from a soil bacterium to an intracellular pathogen of mammalian hosts. The bacterium's impressive ability to adapt to changing environments and conditions requires the rapid sensing of environmental cues and the coordinated response of gene products that enable bacterial growth and survival. Two-component signaling systems (TCSs) have been long recognized for their ability to detect environmental stimuli and transmit those signals into transcriptional responses; however, often the precise nature of the stimulus triggering TCS responses can be challenging to define. L. monocytogenes has up to 16 TCSs that have been recognized based on homology and included in this list are several whose functions remain poorly described. This review highlights the current understanding of the breadth and scope of L. monocytogenes TCS as relates to stress resistance and pathogenesis. Precise signals still often remain elusive, but the gene networks associated with TCSs are providing clues into possible functions.
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Affiliation(s)
| | - Nancy E. Freitag
- Department of Microbiology and Immunology, University of Illinois at Chicago, Chicago, Illinois, USA
- Department of Pharmaceutical Sciences, University of Illinois at Chicago, Chicago, Illinois, USA
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2
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Shaw C, Hess M, Weimer BC. Two-component systems regulate bacterial virulence in response to the host gastrointestinal environment and metabolic cues. Virulence 2022; 13:1666-1680. [PMID: 36128741 PMCID: PMC9518994 DOI: 10.1080/21505594.2022.2127196] [Citation(s) in RCA: 10] [Impact Index Per Article: 5.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 10/26/2022] Open
Abstract
Two-component systems are ubiquitous signaling mechanisms in bacteria that enable intracellular changes from extracellular cues. These bacterial regulatory systems couple external stimuli to control genetic expression via an autophosphorylation cascade that transduces membrane signals to intracellular locations, thereby allowing bacteria to rapidly adapt to the changing environmental conditions. Well known to control basic cellular processes, it is evident that two-component systems also exercise control over virulence traits, such as motility, secretion systems, and stress responses that impact the complex cascade of networks that alter virulence traits. In the gastrointestinal system, cues for activation of virulence-related two-component systems include metal ions, host-derived metabolites, and gut conditions. The diversity and origin of these cues suggest that the host can exert control over enteric pathogenicity via regulation in the gastrointestinal system. With the rise in multi-drug resistant pathogens, the potential control of pathogenicity with host cues via two-component systems presents a potential alternative to antimicrobials. Though the signaling mechanism itself is well studied, to date there is no systematic review compiling the host-associated cues of two-component systems and virulence traits. This review highlights the direct link between the host gastrointestinal environment and pathogenicity by focusing on two-component systems that are associated with the genetic expression of virulence traits, and that are activated by host-derived cues. The direct link between the host gastrointestinal environment, metabolites, and pathogenicity established in this review both underscores the importance of host-derived cues on bacterial activity and presents an enticing therapeutic target in the fight against antimicrobial resistant pathogens.
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Affiliation(s)
- Claire Shaw
- Department of Animal Science, Systems Microbiology & Natural Products Laboratory, University of California, Davis, USA
| | - Matthias Hess
- Department of Animal Science, Systems Microbiology & Natural Products Laboratory, University of California, Davis, USA
| | - Bart C Weimer
- Department of Population Health and Reproduction, 100K Pathogen Genome Project, University of California, Davis, CA, USA
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3
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Michel AM, Borrero-de Acuña JM, Molinari G, Ünal CM, Will S, Derksen E, Barthels S, Bartram W, Schrader M, Rohde M, Zhang H, Hoffmann T, Neumann-Schaal M, Bremer E, Jahn D. Cellular adaptation of Clostridioides difficile to high salinity encompasses a compatible solute-responsive change in cell morphology. Environ Microbiol 2022; 24:1499-1517. [PMID: 35106888 DOI: 10.1111/1462-2920.15925] [Citation(s) in RCA: 3] [Impact Index Per Article: 1.5] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/27/2021] [Revised: 01/24/2022] [Accepted: 01/25/2022] [Indexed: 11/27/2022]
Abstract
Infections by the pathogenic gut bacterium Clostridioides difficile cause severe diarrheas up to a toxic megacolon and are currently among the major causes of lethal bacterial infections. Successful bacterial propagation in the gut is strongly associated with the adaptation to changing nutrition-caused environmental conditions; e.g. environmental salt stresses. Concentrations of 350 mM NaCl, the prevailing salinity in the colon, led to significantly reduced growth of C. difficile. Metabolomics of salt- stressed bacteria revealed a major reduction of the central energy generation pathways, including the Stickland-fermentation reactions. No obvious synthesis of compatible solutes was observed up to 24 h of growth. The ensuing limited tolerance to high salinity and absence of compatible solute synthesis might result from an evolutionary adaptation to the exclusive life of C. difficile in the mammalian gut. Addition of the compatible solutes carnitine, glycine-betaine, γ-butyrobetaine, crotonobetaine, homobetaine, proline-betaine and dimethylsulfoniopropionate (DMSP) restored growth (choline and proline failed) under conditions of high salinity. A bioinformatically-identified OpuF-type ABC-transporter imported most of the used compatible solutes. A long-term adaptation after 48 h included a shift of the Stickland fermentation-based energy metabolism from the utilization to the accumulation of L-proline and resulted in restored growth. Surprisingly, salt stress resulted in the formation of coccoid C. difficile cells instead of the typical rod-shaped cells, a process reverted by the addition of several compatible solutes. Hence, compatible solute import via OpuF is the major immediate adaptation strategy of C. difficile to high salinity-incurred cellular stress. This article is protected by copyright. All rights reserved.
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Affiliation(s)
- Annika-Marisa Michel
- Institute of Microbiology, Technische Universität Braunschweig, Braunschweig, Germany.,Braunschweig Integrated Centre of Systems Biology (BRICS), Technische Universität Braunschweig, Braunschweig, Germany
| | - José Manuel Borrero-de Acuña
- Institute of Microbiology, Technische Universität Braunschweig, Braunschweig, Germany.,Braunschweig Integrated Centre of Systems Biology (BRICS), Technische Universität Braunschweig, Braunschweig, Germany.,Universidad de Sevilla, Facultad de Biología, Departamento de Microbiología, Av. de la Reina Mercedes, n° 6, CP, 41012, Sevilla, Spain
| | - Gabriella Molinari
- Central Facility for Microscopy, Helmholtz Centre for Infection Research (HZI), Braunschweig, Germany
| | - Can Murat Ünal
- Institute of Microbiology, Technische Universität Braunschweig, Braunschweig, Germany
| | - Sabine Will
- Leibniz-Institute DSMZ-German Collection of Microorganisms and Cell Cultures, Braunschweig, Germany
| | - Elisabeth Derksen
- Institute of Microbiology, Technische Universität Braunschweig, Braunschweig, Germany
| | - Stefan Barthels
- Institute of Microbiology, Technische Universität Braunschweig, Braunschweig, Germany.,Braunschweig Integrated Centre of Systems Biology (BRICS), Technische Universität Braunschweig, Braunschweig, Germany
| | - Wiebke Bartram
- Institute of Microbiology, Technische Universität Braunschweig, Braunschweig, Germany.,Braunschweig Integrated Centre of Systems Biology (BRICS), Technische Universität Braunschweig, Braunschweig, Germany
| | - Michel Schrader
- Institute of Microbiology, Technische Universität Braunschweig, Braunschweig, Germany
| | - Manfred Rohde
- Central Facility for Microscopy, Helmholtz Centre for Infection Research (HZI), Braunschweig, Germany
| | - Hao Zhang
- Institute of Microbiology, Technische Universität Braunschweig, Braunschweig, Germany.,School of Life Science and Technology, Changchun University of Science and Technology, No. 7186 Weixing Road, 130022, Changchun, China
| | - Tamara Hoffmann
- Laboratory for Microbiology, Department of Biology, Philipps-Universität Marburg, Marburg, Germany.,Center for Synthetic Microbiology (SYNMIKRO), Philipps-Universität Marburg, Marburg, Germany
| | - Meina Neumann-Schaal
- Braunschweig Integrated Centre of Systems Biology (BRICS), Technische Universität Braunschweig, Braunschweig, Germany.,Leibniz-Institute DSMZ-German Collection of Microorganisms and Cell Cultures, Braunschweig, Germany
| | - Erhard Bremer
- Laboratory for Microbiology, Department of Biology, Philipps-Universität Marburg, Marburg, Germany.,Center for Synthetic Microbiology (SYNMIKRO), Philipps-Universität Marburg, Marburg, Germany
| | - Dieter Jahn
- Institute of Microbiology, Technische Universität Braunschweig, Braunschweig, Germany.,Braunschweig Integrated Centre of Systems Biology (BRICS), Technische Universität Braunschweig, Braunschweig, Germany
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4
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Houeix B, Synowsky S, Cairns MT, Kane M, Kilcoyne M, Joshi L. Identification of putative adhesins and carbohydrate ligands of Lactobacillus paracasei using a combinatorial in silico and glycomics microarray profiling approach. Integr Biol (Camb) 2020; 11:315-329. [PMID: 31712825 DOI: 10.1093/intbio/zyz026] [Citation(s) in RCA: 2] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/28/2019] [Revised: 08/28/2019] [Accepted: 09/02/2019] [Indexed: 01/07/2023]
Abstract
Commensal bacteria must colonize host mucosal surfaces to exert health-promoting properties, and bind to gastrointestinal tract (GIT) mucins via their cell surface adhesins. Considerable effort has been directed towards discovery of pathogen adhesins and their ligands to develop anti-infective strategies; however, little is known about the lectin-like adhesins and associated carbohydrate ligands in commensals. In this study, an in silico approach was used to detect surface exposed adhesins in the human commensal Lactobacillus paracasei subsp. paracasei, a promising probiotic commonly used in dairy product fermentation that presents anti-microbial activity. Of the 13 adhesin candidates, 3 sortase-dependent pili clusters were identified in this strain and expression of the adhesin candidate genes was confirmed in vitro. Mass spectrometry analysis confirmed the presence of surface adhesin elongation factor Tu and the chaperonin GroEL, but not pili expression. Whole cells were subsequently incubated on microarrays featuring a panel of GIT mucins from nine different mammalian species and two human-derived cell lines and a library of carbohydrate structures. Binding profiles were compared to those of two known pili-producing lactobacilli, L. johnsonii and L. rhamnosus and all Lactobacillus species displayed overlapping but distinct signatures, which may indicate different abilities for regiospecific GIT colonization. In addition, L. paracasei whole cells favoured binding to α-(2 → 3)-linked sialic acid and α-(1 → 2)-linked fucose-containing carbohydrate structures including blood groups A, B and O and Lewis antigens x, y and b. This study furthers our understanding of host-commensal cross-talk by identifying potential adhesins and specific GIT mucin and carbohydrate ligands and provides insight into the selection of colonization sites by commensals in the GIT.
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Affiliation(s)
- Benoit Houeix
- Glycoscience Group, School of Natural Sciences, National University of Ireland Galway, Galway, Ireland.,Advanced Glycoscience Research Cluster, National Centre for Biomedical Engineering Science, National University of Ireland Galway, Galway, Ireland
| | - Silvia Synowsky
- Biomedical Sciences Research Complex, University of St. Andrews, St. Andrews, KY16 9ST, UK
| | - Michael T Cairns
- Glycoscience Group, School of Natural Sciences, National University of Ireland Galway, Galway, Ireland.,Advanced Glycoscience Research Cluster, National Centre for Biomedical Engineering Science, National University of Ireland Galway, Galway, Ireland
| | - Marian Kane
- Glycoscience Group, School of Natural Sciences, National University of Ireland Galway, Galway, Ireland.,Advanced Glycoscience Research Cluster, National Centre for Biomedical Engineering Science, National University of Ireland Galway, Galway, Ireland
| | - Michelle Kilcoyne
- Advanced Glycoscience Research Cluster, National Centre for Biomedical Engineering Science, National University of Ireland Galway, Galway, Ireland.,Carbohydrate Signalling Group, Discipline of Microbiology, School of Natural Sciences, National University of Ireland Galway, Galway, Ireland
| | - Lokesh Joshi
- Glycoscience Group, School of Natural Sciences, National University of Ireland Galway, Galway, Ireland.,Advanced Glycoscience Research Cluster, National Centre for Biomedical Engineering Science, National University of Ireland Galway, Galway, Ireland
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5
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Maury MM, Bracq-Dieye H, Huang L, Vales G, Lavina M, Thouvenot P, Disson O, Leclercq A, Brisse S, Lecuit M. Hypervirulent Listeria monocytogenes clones' adaption to mammalian gut accounts for their association with dairy products. Nat Commun 2019; 10:2488. [PMID: 31171794 PMCID: PMC6554400 DOI: 10.1038/s41467-019-10380-0] [Citation(s) in RCA: 123] [Impact Index Per Article: 24.6] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/03/2018] [Accepted: 05/09/2019] [Indexed: 11/09/2022] Open
Abstract
Listeria monocytogenes (Lm) is a major human and animal foodborne pathogen. Here we show that hypervirulent Lm clones, particularly CC1, are strongly associated with dairy products, whereas hypovirulent clones, CC9 and CC121, are associated with meat products. Clone adaptation to distinct ecological niches and/or different food products contamination routes may account for this uneven distribution. Indeed, hypervirulent clones colonize better the intestinal lumen and invade more intestinal tissues than hypovirulent ones, reflecting their adaption to host environment. Conversely, hypovirulent clones are adapted to food processing environments, with a higher prevalence of stress resistance and benzalkonium chloride tolerance genes and a higher survival and biofilm formation capacity in presence of sub-lethal benzalkonium chloride concentrations. Lm virulence heterogeneity therefore reflects the diversity of the ecological niches in which it evolves. These results also have important public health implications and may help in reducing food contamination and improving food consumption recommendations to at-risk populations.
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Affiliation(s)
- Mylène M Maury
- Biology of Infection Unit, Inserm U1117, Institut Pasteur, 75015, Paris, France.,National Reference Centre and WHO Collaborating Centre for Listeria, Institut Pasteur, 75015, Paris, France.,Microbial Evolutionary Genomics Unit, CNRS UMR 3525, Institut Pasteur, 75015, Paris, France
| | - Hélène Bracq-Dieye
- Biology of Infection Unit, Inserm U1117, Institut Pasteur, 75015, Paris, France.,National Reference Centre and WHO Collaborating Centre for Listeria, Institut Pasteur, 75015, Paris, France
| | - Lei Huang
- Biology of Infection Unit, Inserm U1117, Institut Pasteur, 75015, Paris, France.,Université Paris Diderot, Université de Paris, 75013, Paris, France
| | - Guillaume Vales
- Biology of Infection Unit, Inserm U1117, Institut Pasteur, 75015, Paris, France.,National Reference Centre and WHO Collaborating Centre for Listeria, Institut Pasteur, 75015, Paris, France
| | - Morgane Lavina
- Biology of Infection Unit, Inserm U1117, Institut Pasteur, 75015, Paris, France
| | - Pierre Thouvenot
- Biology of Infection Unit, Inserm U1117, Institut Pasteur, 75015, Paris, France.,National Reference Centre and WHO Collaborating Centre for Listeria, Institut Pasteur, 75015, Paris, France
| | - Olivier Disson
- Biology of Infection Unit, Inserm U1117, Institut Pasteur, 75015, Paris, France
| | - Alexandre Leclercq
- Biology of Infection Unit, Inserm U1117, Institut Pasteur, 75015, Paris, France.,National Reference Centre and WHO Collaborating Centre for Listeria, Institut Pasteur, 75015, Paris, France
| | - Sylvain Brisse
- Microbial Evolutionary Genomics Unit, CNRS UMR 3525, Institut Pasteur, 75015, Paris, France.,Biodiversity and Epidemiology of Bacterial Pathogens Unit, Institut Pasteur, 75015, Paris, France
| | - Marc Lecuit
- Biology of Infection Unit, Inserm U1117, Institut Pasteur, 75015, Paris, France. .,National Reference Centre and WHO Collaborating Centre for Listeria, Institut Pasteur, 75015, Paris, France. .,Paris Descartes University, Institut Imagine, Necker-Enfants Malades University Hospital, Division of Infectious Diseases and Tropical Medicine, APHP, 75006, Paris, France.
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6
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Liaquat S, Sarwar Y, Ali A, Haque A. Comparative growth analysis of capsulated (Vi+) and acapsulated (Vi-) Salmonella typhi isolates in human blood. EXCLI JOURNAL 2015; 14:213-9. [PMID: 26417360 PMCID: PMC4553862 DOI: 10.17179/excli2014-674] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.1] [Reference Citation Analysis] [Abstract] [Key Words] [Download PDF] [Figures] [Subscribe] [Scholar Register] [Received: 11/13/2014] [Accepted: 11/27/2014] [Indexed: 11/10/2022]
Abstract
Salmonella enterica serovar Typhi (S. Typhi) is a human restricted pathogen. It biosynthesizes a virulence capsular polysaccharide named as Vi antigen. S. Typhi regulates expression of genes involved in the biosynthesis of Vi antigen in response to osmolarity. Beside Vi-positive isolates, Vi-negative (acapsulated) isolates are also pathogenic. However, Vi-positive isolates are more prevalent. The present study was planned to investigate comparative growth of Vi-positive and Vi-negative S. Typhi isolates in an ex vivo human whole blood model. Four isolates of each type were tested for growth in human whole blood and in an enrichment medium (Tryptic soy broth-TSB) as a control. It was found that capsulated (Vi-positive) strains formed smooth circular colonies and grew with shorter lag and generation time than Vi-negative isolates. Overall growth pattern of S. Typhi isolates both in vitro and ex vivo conditions showed that Vi-positive isolates grew at a faster rate. Especially in human blood, the lag time of acapsulated isolates was almost doubled as compared to capsulated S. Typhi isolates. It was also observed that Vi-negative isolates reduced in number up to 81 % during the first 12 hours of incubation in human whole blood. Interestingly, both types of isolates had similar growth curve in TSB indicating that Vi capsule is dispensable for bacterial growth in vitro. This study shows for the first time that absence of capsular antigen retards the growth of Vi-negative isolates on initial contact with human blood, but with passage of time they adjust themselves according to the new environment.
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Affiliation(s)
- Sadia Liaquat
- Enteric Pathogen Laboratory, Health Biotechnology Division, National Institute for Biotechnology and Genetic Engineering (NIBGE), Faisalabad, Pakistan affiliated with Pakistan Institute of Engineering and Applied Sciences (PIEAS), Islamabad, Pakistan ; Department of Bioinformatics and Biotechnology, GC University, Faisalabad, Pakistan
| | - Yasra Sarwar
- Enteric Pathogen Laboratory, Health Biotechnology Division, National Institute for Biotechnology and Genetic Engineering (NIBGE), Faisalabad, Pakistan affiliated with Pakistan Institute of Engineering and Applied Sciences (PIEAS), Islamabad, Pakistan
| | - Aamir Ali
- Enteric Pathogen Laboratory, Health Biotechnology Division, National Institute for Biotechnology and Genetic Engineering (NIBGE), Faisalabad, Pakistan affiliated with Pakistan Institute of Engineering and Applied Sciences (PIEAS), Islamabad, Pakistan
| | - Abdul Haque
- Dean, Faculty of Health Sciences, University of Faisalabad, Pakistan
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7
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Abstract
The review centers on the human gastrointestinal tract; focusing first on the bacterial stress responses needed to overcome the physiochemical defenses of the host, specifically how these stress survival strategies can be used as targets for alternative infection control strategies. The concluding section focuses on recent developments in molecular diagnostics; centring on the shifting paradigm from culture to molecular based diagnostics.
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Affiliation(s)
- Roy D Sleator
- a Department of Biological Sciences ; Cork Institute of Technology ; Bishopstown , Cork , Ireland
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8
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Sleator RD. Designer probiotics: Development and applications in gastrointestinal health. World J Gastrointest Pathophysiol 2015; 6:73-78. [PMID: 26301121 PMCID: PMC4540709 DOI: 10.4291/wjgp.v6.i3.73] [Citation(s) in RCA: 11] [Impact Index Per Article: 1.2] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 03/11/2015] [Revised: 04/23/2015] [Accepted: 07/14/2015] [Indexed: 02/06/2023] Open
Abstract
Given the increasing commercial and clinical relevance of probiotics, improving their stress tolerance profile and ability to overcome the physiochemical defences of the host is an important biological goal. Herein, I review the current state of the art in the design of engineered probiotic cultures, with a specific focus on their utility as therapeutics for the developing world; from the treatment of chronic and acute enteric infections, and their associated diarrhoeal complexes, to targeting HIV and application as novel mucosal vaccine delivery vehicles.
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9
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Feeney A, Kropp KA, O’Connor R, Sleator RD. Cronobacter sakazakii: stress survival and virulence potential in an opportunistic foodborne pathogen. Gut Microbes 2015; 5:711-8. [PMID: 25562731 PMCID: PMC4615781 DOI: 10.4161/19490976.2014.983774] [Citation(s) in RCA: 45] [Impact Index Per Article: 5.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Indexed: 02/03/2023] Open
Abstract
A characteristic feature of the opportunistic foodborne pathogen Cronobacter sakazakii is its ability to survive in extremely arid environments, such as powdered infant formula, making it a dangerous opportunistic pathogen of individuals of all age groups, especially infants and neonates. Herein, we provide a brief overview of the pathogen; clinical manifestations, environmental reservoirs and our current understanding of stress response mechanisms and virulence factors which allow it to cause disease.
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Affiliation(s)
- Audrey Feeney
- Department of Biological Sciences; Cork Institute of Technology; Bishopstown, Cork, Ireland
| | - Kai A Kropp
- Department of Biological Sciences; Cork Institute of Technology; Bishopstown, Cork, Ireland
| | - Roxana O’Connor
- Department of Biological Sciences; Cork Institute of Technology; Bishopstown, Cork, Ireland
| | - Roy D Sleator
- Department of Biological Sciences; Cork Institute of Technology; Bishopstown, Cork, Ireland,Correspondence to: Roy D Sleator;
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10
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Cummins J, Casey PG, Joyce SA, Gahan CGM. A mariner transposon-based signature-tagged mutagenesis system for the analysis of oral infection by Listeria monocytogenes. PLoS One 2013; 8:e75437. [PMID: 24069416 PMCID: PMC3771922 DOI: 10.1371/journal.pone.0075437] [Citation(s) in RCA: 13] [Impact Index Per Article: 1.2] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/13/2013] [Accepted: 08/14/2013] [Indexed: 11/18/2022] Open
Abstract
Listeria monocytogenes is a Gram-positive foodborne pathogen and the causative agent of listerosis a disease that manifests predominately as meningitis in the non-pregnant individual or infection of the fetus and spontaneous abortion in pregnant women. Common-source outbreaks of foodborne listeriosis are associated with significant morbidity and mortality. However, relatively little is known concerning the mechanisms that govern infection via the oral route. In order to aid functional genetic analysis of the gastrointestinal phase of infection we designed a novel signature-tagged mutagenesis (STM) system based upon the invasive L. monocytogenes 4b serotype H7858 strain. To overcome the limitations of gastrointestinal infection by L. monocytogenes in the mouse model we created a H7858 strain that is genetically optimised for oral infection in mice. Furthermore our STM system was based upon a mariner transposon to favour numerous and random transposition events throughout the L. monocytogenes genome. Use of the STM bank to investigate oral infection by L. monocytogenes identified 21 insertion mutants that demonstrated significantly reduced potential for infection in our model. The sites of transposon insertion included lmOh7858_0671 (encoding an internalin homologous to Lmo0610), lmOh7858_0898 (encoding a putative surface-expressed LPXTG protein homologous to Lmo0842), lmOh7858_2579 (encoding the HupDGC hemin transport system) and lmOh7858_0399 (encoding a putative fructose specific phosphotransferase system). We propose that this represents an optimised STM system for functional genetic analysis of foodborne/oral infection by L. monocytogenes.
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Affiliation(s)
- Joanne Cummins
- Department of Microbiology, University College Cork, Cork, Ireland
| | - Pat G. Casey
- Department of Microbiology, University College Cork, Cork, Ireland
- Alimentary Pharmabiotic Centre, University College Cork, Cork, Ireland
| | - Susan A. Joyce
- Department of Microbiology, University College Cork, Cork, Ireland
- Alimentary Pharmabiotic Centre, University College Cork, Cork, Ireland
| | - Cormac G. M. Gahan
- Department of Microbiology, University College Cork, Cork, Ireland
- Alimentary Pharmabiotic Centre, University College Cork, Cork, Ireland
- School of Pharmacy, University College Cork, Cork, Ireland
- * E-mail:
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11
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Cheng C, Chen J, Shan Y, Fang C, Liu Y, Xia Y, Song H, Fang W. Listeria monocytogenes ArcA contributes to acid tolerance. J Med Microbiol 2013; 62:813-821. [PMID: 23518652 DOI: 10.1099/jmm.0.055145-0] [Citation(s) in RCA: 16] [Impact Index Per Article: 1.5] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/18/2022] Open
Abstract
The foodborne pathogen Listeria monocytogenes is able to colonize the human and animal intestinal tracts and subsequently crosses the intestinal barrier, causing systemic infection. For successful establishment of infection, L. monocytogenes must survive and adapt to the low pH environment of the stomach. Gene sequence analysis indicates that lmo0043, an orthologue of arcA, encodes a protein containing conserved motifs and critical active amino acids characteristic of arginine deiminase that mediates an arginine deimination reaction. We attempted to characterize the role of ArcA in acid tolerance in vitro and in mice models. Transcription of arcA was significantly increased in L. monocytogenes culture subjected to acid stress at pH 4.8, as compared with that at pH 7.0. Deletion of arcA impaired growth of L. monocytogenes under mild acidic conditions at pH 5.5, and reduced its survival in synthetic human gastric fluid at pH 2.5 and in the murine stomach. Bacterial load in the spleen of mice intraperitoneally inoculated with an arcA deletion mutant was significantly lower than that of the wild-type strain. These phenotypic changes were recoverable by genetic complementation. Thus, we conclude that L. monocytogenes arcA not only mediates acid tolerance in vitro but also participates in gastric survival and virulence in mice.
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Affiliation(s)
- Changyong Cheng
- Zhejiang University Institute of Preventive Veterinary Medicine and Zhejiang Provincial Key Laboratory of Preventive Veterinary Medicine, 388 Yuhangtang Road, Hangzhou, Zhejiang 310058, PR China
| | - Jianshun Chen
- Zhejiang Aquatic Disease Prevention and Quarantine Center, 20 Yile Road, Hangzhou, Zhejiang 310012, PR China
| | - Ying Shan
- Zhejiang University Institute of Preventive Veterinary Medicine and Zhejiang Provincial Key Laboratory of Preventive Veterinary Medicine, 388 Yuhangtang Road, Hangzhou, Zhejiang 310058, PR China
| | - Chun Fang
- Zhejiang University Institute of Preventive Veterinary Medicine and Zhejiang Provincial Key Laboratory of Preventive Veterinary Medicine, 388 Yuhangtang Road, Hangzhou, Zhejiang 310058, PR China
| | - Yuan Liu
- Zhejiang University Institute of Preventive Veterinary Medicine and Zhejiang Provincial Key Laboratory of Preventive Veterinary Medicine, 388 Yuhangtang Road, Hangzhou, Zhejiang 310058, PR China
| | - Ye Xia
- Zhejiang University Institute of Preventive Veterinary Medicine and Zhejiang Provincial Key Laboratory of Preventive Veterinary Medicine, 388 Yuhangtang Road, Hangzhou, Zhejiang 310058, PR China
| | - Houhui Song
- Zhejiang A&F University College of Animal Science & Technology, Lin'an, Zhejiang 311300, PR China
| | - Weihuan Fang
- Zhejiang A&F University College of Animal Science & Technology, Lin'an, Zhejiang 311300, PR China.,Zhejiang University Institute of Preventive Veterinary Medicine and Zhejiang Provincial Key Laboratory of Preventive Veterinary Medicine, 388 Yuhangtang Road, Hangzhou, Zhejiang 310058, PR China
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12
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Different assembly of acid and salt tolerance response in two dairy Listeria monocytogenes wild strains. Arch Microbiol 2013; 195:339-48. [DOI: 10.1007/s00203-013-0878-6] [Citation(s) in RCA: 6] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/02/2012] [Revised: 02/11/2013] [Accepted: 02/14/2013] [Indexed: 01/11/2023]
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13
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Cummins J, Gahan CG. Signature tagged mutagenesis in the functional genetic analysis of gastrointestinal pathogens. Gut Microbes 2012; 3:93-103. [PMID: 22555467 PMCID: PMC3370953 DOI: 10.4161/gmic.19578] [Citation(s) in RCA: 8] [Impact Index Per Article: 0.7] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Indexed: 02/03/2023] Open
Abstract
Signature tagged mutagenesis is a genetic approach that was developed to identify novel bacterial virulence factors. It is a negative selection method in which unique identification tags allow analysis of pools of mutants in mixed populations. The approach is particularly well suited to functional genetic analysis of the gastrointestinal phase of infection in foodborne pathogens and has the capacity to guide the development of novel vaccines and therapeutics. In this review we outline the technical principles underpinning signature-tagged mutagenesis as well as novel sequencing-based approaches for transposon mutant identification such as TraDIS (transposon directed insertion-site sequencing). We also provide an analysis of screens that have been performed in gastrointestinal pathogens which are a global health concern (Escherichia coli, Listeria monocytogenes, Helicobacter pylori, Vibrio cholerae and Salmonella enterica). The identification of key virulence loci through the use of signature tagged mutagenesis in mice and relevant larger animal models is discussed.
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Affiliation(s)
- Joanne Cummins
- Alimentary Pharmabiotic Centre; University College Cork; Cork, Ireland,Department of Microbiology; University College Cork; Cork, Ireland
| | - Cormac G.M. Gahan
- Alimentary Pharmabiotic Centre; University College Cork; Cork, Ireland,Department of Microbiology; University College Cork; Cork, Ireland,School of Pharmacy; University College Cork; Cork, Ireland,Correspondence to: Cormac G.M. Gahan,
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Listeria monocytogenes shows temperature-dependent and -independent responses to salt stress, including responses that induce cross-protection against other stresses. Appl Environ Microbiol 2012; 78:2602-12. [PMID: 22307309 DOI: 10.1128/aem.07658-11] [Citation(s) in RCA: 82] [Impact Index Per Article: 6.8] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/16/2023] Open
Abstract
The food-borne pathogen Listeria monocytogenes experiences osmotic stress in many habitats, including foods and the gastrointestinal tract of the host. During transmission, L. monocytogenes is likely to experience osmotic stress at different temperatures and may adapt to osmotic stress in a temperature-dependent manner. To understand the impact of temperature on the responses this pathogen uses to adapt to osmotic stress, we assessed genome-wide changes in the L. monocytogenes H7858 transcriptome during short-term and long-term adaptation to salt stress at 7°C and 37°C. At both temperatures, the short-term response to salt stress included increased transcript levels of sigB and SigB-regulated genes, as well as mrpABCDEFG, encoding a sodium/proton antiporter. This antiporter was found to play a role in adaptation to salt stress at both temperatures; ΔmrpABCDEFG had a significantly longer lag phase than the parent strain in BHI plus 6% NaCl at 7°C and 37°C. The short-term adaptation to salt stress at 7°C included increased transcript levels of two genes encoding carboxypeptidases that modify peptidoglycan. These carboxypeptidases play a role in the short-term adaptation to salt stress only at 7°C, where the deletion mutants had significantly different lag phases than the parent strain. Changes in the transcriptome at both temperatures suggested that exposure to salt stress could provide cross-protection to other stresses, including peroxide stress. Short-term exposure to salt stress significantly increased H(2)O(2) resistance at both temperatures. These results provide information for the development of knowledge-based intervention methods against this pathogen, as well as provide insight into potential mechanisms of cross-protection.
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Bergholz TM, den Bakker HC, Fortes ED, Boor KJ, Wiedmann M. Salt stress phenotypes in Listeria monocytogenes vary by genetic lineage and temperature. Foodborne Pathog Dis 2010; 7:1537-49. [PMID: 20707723 PMCID: PMC3022828 DOI: 10.1089/fpd.2010.0624] [Citation(s) in RCA: 53] [Impact Index Per Article: 3.8] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/15/2023] Open
Abstract
Listeria monocytogenes can survive and grow under wide-ranging environmental stress conditions encountered both in foods and in the host. The ability of certain L. monocytogenes subtypes to thrive under stress conditions present in specific niches was hypothesized to reflect genetic characteristics and phenotypic capabilities conserved among strains within a subtype. To quantify variations in salt stress phenotypes among 40 strains selected to represent the diversity of the three major L. monocytogenes genetic lineages and to determine if salt stress phenotypes were associated with genetic relatedness, we measured growth under salt stress at both 7°C and 37°C. At 7°C, in brain-heart infusion with 6% NaCl, average growth rates among the lineages were similar. A comparison of doubling times after exposure to salt stress at 7°C or 37°C indicated that growth at 7°C provided crossprotection to subsequent salt stress for strains in lineages I and II. At 37°C, in brain-heart infusion with 6% NaCl, lineage I and III strains grew significantly faster (p<0.0001) than lineage II strains. Under salt stress at 37°C, differences in growth parameters were significantly (p<0.005) associated with genetic relatedness of the strains. Compatible solute uptake is part of the L. monocytogenes salt stress response, but growth differences between the lineages were not related to differences in transcript levels of osmolyte transporter-encoding genes betL, gbuA, oppA, and opuCA. The combination of phylogenetic and phenotypic data suggests that L. monocytogenes lineage I and III strains, which are most commonly associated with human and animal disease, may be better adapted to osmotic stress at 37°C, conditions that are present in the host gastrointestinal tract.
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Affiliation(s)
- Teresa M Bergholz
- Department of Food Science, Cornell University, Ithaca, New York 14853, USA.
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16
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Ramalheira R, Almeida M, Azeredo J, Brandão TR, Almeida G, Silva J, Teixeira P. Survival of Clinical and Food Isolates of Listeria monocytogenes Through Simulated Gastrointestinal Tract Conditions. Foodborne Pathog Dis 2010; 7:121-8. [DOI: 10.1089/fpd.2009.0319] [Citation(s) in RCA: 20] [Impact Index Per Article: 1.4] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/12/2022] Open
Affiliation(s)
- Rosário Ramalheira
- CBQF/Biotechnology School, Portuguese Catholic University, Oporto, Portugal
| | - Marta Almeida
- Biological Engineering Department, University of Minho, Braga, Portugal
| | - Joana Azeredo
- Biological Engineering Department, University of Minho, Braga, Portugal
| | | | - Gonçalo Almeida
- CBQF/Biotechnology School, Portuguese Catholic University, Oporto, Portugal
| | - Joana Silva
- CBQF/Biotechnology School, Portuguese Catholic University, Oporto, Portugal
| | - Paula Teixeira
- CBQF/Biotechnology School, Portuguese Catholic University, Oporto, Portugal
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Abstract
The complex physical and chemical conditions encountered in the gut present a range of physiological challenges to both the commensal microbiota and to pathogenic microorganisms attempting to colonise the gut. The innate immune system of the host, the host's diet and the microbial population present in the gut all contribute to the chemical complexity of the environment. The huge population of microorganisms in the gut also has a significant impact on the physicochemical properties of the gut environment. By focussing on some of the key physical and chemical stresses encountered by microorganisms in the gut, some of the molecular responses are described. Some promising new experimental approaches are outlined for studying the behaviour of microorganisms and their communities within the gut environment.
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Affiliation(s)
- Petra Louis
- Microbial Ecology Group, Gut Health Programme, Rowett Institute of Nutrition and Health, University of Aberdeen, Greenburn Road, Bucks-burn, Aberdeen AB21 9SB, UK
| | - Conor P. O'Byrne
- Bacterial Stress Response Group, Microbiology, School of Natural Sciences, National University of Ireland, Galway, Ireland
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18
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Oliver HF, Orsi RH, Ponnala L, Keich U, Wang W, Sun Q, Cartinhour SW, Filiatrault MJ, Wiedmann M, Boor KJ. Deep RNA sequencing of L. monocytogenes reveals overlapping and extensive stationary phase and sigma B-dependent transcriptomes, including multiple highly transcribed noncoding RNAs. BMC Genomics 2009; 10:641. [PMID: 20042087 PMCID: PMC2813243 DOI: 10.1186/1471-2164-10-641] [Citation(s) in RCA: 145] [Impact Index Per Article: 9.7] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/01/2009] [Accepted: 12/30/2009] [Indexed: 11/30/2022] Open
Abstract
Background Identification of specific genes and gene expression patterns important for bacterial survival, transmission and pathogenesis is critically needed to enable development of more effective pathogen control strategies. The stationary phase stress response transcriptome, including many σB-dependent genes, was defined for the human bacterial pathogen Listeria monocytogenes using RNA sequencing (RNA-Seq) with the Illumina Genome Analyzer. Specifically, bacterial transcriptomes were compared between stationary phase cells of L. monocytogenes 10403S and an otherwise isogenic ΔsigB mutant, which does not express the alternative σ factor σB, a major regulator of genes contributing to stress response, including stresses encountered upon entry into stationary phase. Results Overall, 83% of all L. monocytogenes genes were transcribed in stationary phase cells; 42% of currently annotated L. monocytogenes genes showed medium to high transcript levels under these conditions. A total of 96 genes had significantly higher transcript levels in 10403S than in ΔsigB, indicating σB-dependent transcription of these genes. RNA-Seq analyses indicate that a total of 67 noncoding RNA molecules (ncRNAs) are transcribed in stationary phase L. monocytogenes, including 7 previously unrecognized putative ncRNAs. Application of a dynamically trained Hidden Markov Model, in combination with RNA-Seq data, identified 65 putative σB promoters upstream of 82 of the 96 σB-dependent genes and upstream of the one σB-dependent ncRNA. The RNA-Seq data also enabled annotation of putative operons as well as visualization of 5'- and 3'-UTR regions. Conclusions The results from these studies provide powerful evidence that RNA-Seq data combined with appropriate bioinformatics tools allow quantitative characterization of prokaryotic transcriptomes, thus providing exciting new strategies for exploring transcriptional regulatory networks in bacteria. See minireivew http://jbiol.com/content/8/12/107.
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Affiliation(s)
- Haley F Oliver
- Department of Food Science, Cornell University, Ithaca, NY, USA.
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19
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Sleator RD, Watson D, Hill C, Gahan CGM. The interaction between Listeria monocytogenes and the host gastrointestinal tract. MICROBIOLOGY-SGM 2009; 155:2463-2475. [PMID: 19542009 DOI: 10.1099/mic.0.030205-0] [Citation(s) in RCA: 77] [Impact Index Per Article: 5.1] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 01/04/2023]
Abstract
Listeria monocytogenes is a ubiquitous bacterium that causes significant foodborne disease with high mortality rates in immunocompromised adults. In pregnant women foodborne infection can give rise to infection of the fetus resulting in miscarriage. In addition, the bacterium has recently been demonstrated to cause localized gastrointestinal symptoms, predominantly in immunocompetent individuals. The murine model of systemic L. monocytogenes infection has provided numerous insights into the mechanisms of pathogenesis of this organism. However, recent application of transcriptomic and proteomic approaches as well as the development of new model systems has allowed a focus upon factors that influence adaptation to gastrointestinal environments and adhesion to and invasion of the gastrointestinal mucosa. In addition, the availability of a large number of complete L. monocytogenes genome sequences has permitted inter-strain comparisons and the identification of factors that may influence the emergence of 'epidemic' phenotypes. Here we review some of the exciting recent developments in the analysis of the interaction between L. monocytogenes and the host gastrointestinal tract.
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Affiliation(s)
- Roy D Sleator
- Alimentary Pharmabiotic Centre, University College Cork, Cork, Ireland
| | - Debbie Watson
- Department of Microbiology, University College Cork, Cork, Ireland
- Alimentary Pharmabiotic Centre, University College Cork, Cork, Ireland
| | - Colin Hill
- Department of Microbiology, University College Cork, Cork, Ireland
- Alimentary Pharmabiotic Centre, University College Cork, Cork, Ireland
| | - Cormac G M Gahan
- School of Pharmacy, University College Cork, Cork, Ireland
- Department of Microbiology, University College Cork, Cork, Ireland
- Alimentary Pharmabiotic Centre, University College Cork, Cork, Ireland
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O'Byrne CP, Karatzas KAG. The role of sigma B (sigma B) in the stress adaptations of Listeria monocytogenes: overlaps between stress adaptation and virulence. ADVANCES IN APPLIED MICROBIOLOGY 2009; 65:115-40. [PMID: 19026864 DOI: 10.1016/s0065-2164(08)00605-9] [Citation(s) in RCA: 70] [Impact Index Per Article: 4.7] [Reference Citation Analysis] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 10/21/2022]
Affiliation(s)
- Conor P O'Byrne
- Department of Microbiology, School of Natural Sciences, National University of Ireland Galway, Galway, Ireland
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21
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Genes and molecules of lactobacilli supporting probiotic action. Microbiol Mol Biol Rev 2009; 72:728-64, Table of Contents. [PMID: 19052326 DOI: 10.1128/mmbr.00017-08] [Citation(s) in RCA: 613] [Impact Index Per Article: 40.9] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/15/2022] Open
Abstract
Lactobacilli have been crucial for the production of fermented products for centuries. They are also members of the mutualistic microbiota present in the human gastrointestinal and urogenital tract. Recently, increasing attention has been given to their probiotic, health-promoting capacities. Many human intervention studies demonstrating health effects have been published. However, as not all studies resulted in positive outcomes, scientific interest arose regarding the precise mechanisms of action of probiotics. Many reported mechanistic studies have addressed mainly the host responses, with less attention being focused on the specificities of the bacterial partners, notwithstanding the completion of Lactobacillus genome sequencing projects, and increasing possibilities of genomics-based and dedicated mutant analyses. In this emerging and highly interdisciplinary field, microbiologists are facing the challenge of molecular characterization of probiotic traits. This review addresses the advances in the understanding of the probiotic-host interaction with a focus on the molecular microbiology of lactobacilli. Insight into the molecules and genes involved should contribute to a more judicious application of probiotic lactobacilli and to improved screening of novel potential probiotics.
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Abstract
The bacterium Listeria monocytogenes is the causative agent of listeriosis, a highly fatal opportunistic foodborne infection. Listeria spp. are isolated from a diversity of environmental sources, including soil, water, effluents, a large variety of foods, and the feces of humans and animals. Recent outbreaks demonstrated that L. monocytogenes can cause gastroenteritis in otherwise healthy individuals and more severe invasive disease in immunocompromised patients. Common symptoms include fever, watery diarrhea, nausea, headache, and pains in joints and muscles. The intestinal tract is the major portal of entry for L. monocytogenes, whereby strains penetrate the mucosal tissue either directly, via invasion of enterocytes, or indirectly, via active penetration of the Peyer's patches. Studies have revealed the strategy taken by the bacteria to overcome changes in oxygen tension, osmolarity, acidity, and the sterilizing effects of bile or antimicrobial peptides to adapt to conditions in the gut. In addition, L. monocytogenes has evolved species-specific strategies for intestinal entry by exploiting the interaction between the internalin protein and its receptor E-cadherin, or inducing diarrhea and an inflammatory response via the activity of its hemolytic toxin, listeriolysin. The ability of these bacteria to survive in bile-rich environments, and to induce depletion of sentinel cells such as Paneth cells that monitor the luminal burden of commensal bacteria, suggest strategies that have evolved to promote intestinal survival. Preexisting gastrointestinal disease may be a risk factor for infection of the gastrointestinal tract with L. monocytogenes. Currently, there is enough evidence to warrant consideration of L. monocytogenes as a possible etiology in outbreaks of febrile gastroenteritis, and for further studies to examine the genetic structure of Listeria strains that have a propensity to cause gastrointestinal versus systemic infections.
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Sheehan VM, Sleator RD, Hill C, Fitzgerald GF. Improving gastric transit, gastrointestinal persistence and therapeutic efficacy of the probiotic strain Bifidobacterium breve UCC2003. MICROBIOLOGY-SGM 2007; 153:3563-3571. [PMID: 17906153 DOI: 10.1099/mic.0.2007/006510-0] [Citation(s) in RCA: 71] [Impact Index Per Article: 4.2] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 12/12/2022]
Abstract
Given the increasing commercial and clinical relevance of probiotic cultures, improving their stress tolerance profile and ability to overcome the physiological defences of the host is an important biological goal. In order to reach the gastrointestinal tract in sufficient numbers to exert a therapeutic effect, probiotic bacteria must resist the deleterious actions of low pH, elevated osmolarity and bile salts. Cloning the listerial betaine uptake system, BetL, into the probiotic strain Bifidobacterium breve UCC2003 significantly improved probiotic tolerance to gastric juice and conditions of elevated osmolarity mimicking the gut environment. Furthermore, whilst stable colonization of the murine intestine was achieved by oral administration of B. breve UCC2003, strains harbouring BetL were recovered at significantly higher levels in the faeces, intestines and caecum of inoculated animals. Finally, in addition to improved gastric transit and intestinal persistence, this approach improved the clinical efficacy of the probiotic culture: mice fed B. breve UCC2003-BetL(+) exhibited significantly lower levels of systemic infection compared to the control strain following oral inoculation with Listeria monocytogenes.
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Affiliation(s)
| | - Roy D Sleator
- Alimentary Pharmabiotic Centre, University College Cork, Ireland
| | - Colin Hill
- Alimentary Pharmabiotic Centre, University College Cork, Ireland
- Department of Microbiology, University College Cork, Ireland
| | - Gerald F Fitzgerald
- Alimentary Pharmabiotic Centre, University College Cork, Ireland
- Department of Microbiology, University College Cork, Ireland
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