1
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Strain R, Stanton C, Ross RP. Effect of diet on pathogen performance in the microbiome. MICROBIOME RESEARCH REPORTS 2022; 1:13. [PMID: 38045644 PMCID: PMC10688830 DOI: 10.20517/mrr.2021.10] [Citation(s) in RCA: 2] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Figures] [Subscribe] [Scholar Register] [Received: 12/02/2021] [Revised: 02/17/2022] [Accepted: 02/23/2022] [Indexed: 12/05/2023]
Abstract
Intricate interactions among commensal bacteria, dietary substrates and immune responses are central to defining microbiome community composition, which plays a key role in preventing enteric pathogen infection, a dynamic phenomenon referred to as colonisation resistance. However, the impact of diet on sculpting microbiota membership, and ultimately colonisation resistance has been overlooked. Furthermore, pathogens have evolved strategies to evade colonisation resistance and outcompete commensal microbiota by using unique nutrient utilisation pathways, by exploiting microbial metabolites as nutrient sources or by environmental cues to induce virulence gene expression. In this review, we will discuss the interplay between diet, microbiota and their associated metabolites, and how these can contribute to or preclude pathogen survival.
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Affiliation(s)
- Ronan Strain
- APC Microbiome Ireland, Biosciences Institute, University College Cork, Cork T12 YT20, Ireland
- Teagasc Food Research Centre, Moorepark, Fermoy, Co. Cork P61 C996, Ireland
| | - Catherine Stanton
- APC Microbiome Ireland, Biosciences Institute, University College Cork, Cork T12 YT20, Ireland
- Teagasc Food Research Centre, Moorepark, Fermoy, Co. Cork P61 C996, Ireland
| | - R. Paul Ross
- APC Microbiome Ireland, Biosciences Institute, University College Cork, Cork T12 YT20, Ireland
- School of Microbiology, University College Cork, College Road, Cork T12 K8AF, Ireland
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2
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Mirzaei R, Dehkhodaie E, Bouzari B, Rahimi M, Gholestani A, Hosseini-Fard SR, Keyvani H, Teimoori A, Karampoor S. Dual role of microbiota-derived short-chain fatty acids on host and pathogen. Biomed Pharmacother 2021; 145:112352. [PMID: 34840032 DOI: 10.1016/j.biopha.2021.112352] [Citation(s) in RCA: 63] [Impact Index Per Article: 21.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/26/2021] [Revised: 10/15/2021] [Accepted: 10/19/2021] [Indexed: 12/12/2022] Open
Abstract
A growing body of documents shows microbiota produce metabolites such as short-chain fatty acids (SCFAs) as crucial executors of diet-based microbial influence the host and bacterial pathogens. The production of SCFAs depends on the metabolic activity of intestinal microflora and is also affected by dietary changes. SCFAs play important roles in maintaining colonic health as an energy source, as a regulator of gene expression and cell differentiation, and as an anti-inflammatory agent. Additionally, the regulated expression of virulence genes is critical for successful infection by an intestinal pathogen. Bacteria rely on sensing environmental signals to find preferable niches and reach the infectious state. This review will present data supporting the diverse functional roles of microbiota-derived butyrate, propionate, and acetate on host cellular activities such as immune modulation, energy metabolism, nervous system, inflammation, cellular differentiation, and anti-tumor effects, among others. On the other hand, we will discuss and summarize data about the role of these SCFAs on the virulence factor of bacterial pathogens. In this regard, receptors and signaling routes for SCFAs metabolites in host and pathogens will be introduced.
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Affiliation(s)
- Rasoul Mirzaei
- Department of Microbiology, School of Medicine, Hamadan University of Medical Sciences, Hamadan, Iran; Venom and Biotherapeutics Molecules Lab, Medical Biotechnology Department, Biotechnology Research Center, Pasteur Institute of Iran, Tehran, Iran.
| | - Elahe Dehkhodaie
- Department of Biology, Science and Research Branch, Islamic Azad University Tehran, Iran
| | - Behnaz Bouzari
- Department of Pathology, Firouzgar Hospital, Iran University of Medical Sciences, Tehran, Iran
| | - Mandana Rahimi
- Department of Pathology, School of Medicine, Hasheminejad Kidney Center, Iran University of Medical Sciences, Tehran, Iran
| | - Abolfazl Gholestani
- Department of Biochemistry, School of Medicine, Tehran University of Medical Sciences, Tehran, Iran
| | - Seyed Reza Hosseini-Fard
- Department of Biochemistry, School of Medicine, Tehran University of Medical Sciences, Tehran, Iran
| | - Hossein Keyvani
- Gastrointestinal and Liver Diseases Research Center, Iran University of Medical Sciences, Tehran, Iran; Department of Virology, School of Medicine, Iran University of Medical Sciences, Tehran, Iran.
| | - Ali Teimoori
- Department of Virology, School of Medicine, Hamadan University of Medical Sciences, Hamadan, Iran.
| | - Sajad Karampoor
- Gastrointestinal and Liver Diseases Research Center, Iran University of Medical Sciences, Tehran, Iran; Department of Virology, School of Medicine, Iran University of Medical Sciences, Tehran, Iran.
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3
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Rauf A, Khalil AA, Rahman UU, Khalid A, Naz S, Shariati MA, Rebezov M, Urtecho EZ, de Albuquerque RDDG, Anwar S, Alamri A, Saini RK, Rengasamy KRR. Recent advances in the therapeutic application of short-chain fatty acids (SCFAs): An updated review. Crit Rev Food Sci Nutr 2021; 62:6034-6054. [PMID: 33703960 DOI: 10.1080/10408398.2021.1895064] [Citation(s) in RCA: 53] [Impact Index Per Article: 17.7] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 02/08/2023]
Abstract
Over the past decade, the gut microbiota has emerged as an important frontier in understanding the human body's homeostasis and the development of diseases. Gut flora in human beings regulates various metabolic functionalities, including enzymes, amino acid synthesis, bio-transformation of bile acid, fermentation of non-digestible carbohydrates (NDCs), generation of indoles and polyamines (PAs), and production of short-chain fatty acids (SCFAs). Among all the metabolites produced by gut microbiota, SCFAs, the final product of fermentation of dietary fibers by gut microbiota, receive lots of attention from scientists due to their pharmacological and physiological characteristics. However, the molecular mechanisms underlying the role of SCFAs in the interaction between diet, gut microbiota, and host energy metabolism is still needed in-depth research. This review highlights the recent biotechnological advances in applying SCFAs as important metabolites to treat various diseases and maintain colonic health.
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Affiliation(s)
- Abdur Rauf
- Department of Chemistry, University of Swabi, Swabi, Anbar, Khyber Pakhtunkhwa (KP), Pakistan
| | - Anees Ahmed Khalil
- University Institute of Diet and Nutritional Sciences, Faculty of Allied Health Sciences, The University of Lahore, Pakistan
| | - Ubaid-Ur- Rahman
- School of Food and Agricultural Sciences, University of Management and Technology, Lahore, Pakistan
| | - Ahood Khalid
- University Institute of Diet and Nutritional Sciences, Faculty of Allied Health Sciences, The University of Lahore, Pakistan
| | - Saima Naz
- Deaprtment of Biotechnology, Woman University Mardan, Mardan, Khyber Pakhtunkhwa (KP), Pakistan
| | - Mohammad Ali Shariati
- K.G. Razumovsky, Moscow State University of Technologies and Management (the First Cossack University), Moscow, Russian
| | - Maksim Rebezov
- V.M. Gorbatov Federal Research Center for Food Systems of Russian Academy of Sciences, Moscow, Russian.,Prokhorov General Physics Institute of the, Russian Academy of Science, Moscow, Russian
| | | | | | - Sirajudheen Anwar
- Department of Pharmacology & Toxicology, College of Pharmacy, University of Hail, Hail, KSA
| | - Abdulwahab Alamri
- Department of Pharmacology & Toxicology, College of Pharmacy, University of Hail, Hail, KSA
| | | | - Kannan R R Rengasamy
- Indigenous Knowledge Systems Centre, Faculty of Natural and Agricultural Sciences, North-West University, Mmabatho, North West Province, South Africa
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4
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Ageorges V, Monteiro R, Leroy S, Burgess CM, Pizza M, Chaucheyras-Durand F, Desvaux M. Molecular determinants of surface colonisation in diarrhoeagenic Escherichia coli (DEC): from bacterial adhesion to biofilm formation. FEMS Microbiol Rev 2021; 44:314-350. [PMID: 32239203 DOI: 10.1093/femsre/fuaa008] [Citation(s) in RCA: 27] [Impact Index Per Article: 9.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/15/2019] [Accepted: 03/31/2020] [Indexed: 12/11/2022] Open
Abstract
Escherichia coli is primarily known as a commensal colonising the gastrointestinal tract of infants very early in life but some strains being responsible for diarrhoea, which can be especially severe in young children. Intestinal pathogenic E. coli include six pathotypes of diarrhoeagenic E. coli (DEC), namely, the (i) enterotoxigenic E. coli, (ii) enteroaggregative E. coli, (iii) enteropathogenic E. coli, (iv) enterohemorragic E. coli, (v) enteroinvasive E. coli and (vi) diffusely adherent E. coli. Prior to human infection, DEC can be found in natural environments, animal reservoirs, food processing environments and contaminated food matrices. From an ecophysiological point of view, DEC thus deal with very different biotopes and biocoenoses all along the food chain. In this context, this review focuses on the wide range of surface molecular determinants acting as surface colonisation factors (SCFs) in DEC. In the first instance, SCFs can be broadly discriminated into (i) extracellular polysaccharides, (ii) extracellular DNA and (iii) surface proteins. Surface proteins constitute the most diverse group of SCFs broadly discriminated into (i) monomeric SCFs, such as autotransporter (AT) adhesins, inverted ATs, heat-resistant agglutinins or some moonlighting proteins, (ii) oligomeric SCFs, namely, the trimeric ATs and (iii) supramolecular SCFs, including flagella and numerous pili, e.g. the injectisome, type 4 pili, curli chaperone-usher pili or conjugative pili. This review also details the gene regulatory network of these numerous SCFs at the various stages as it occurs from pre-transcriptional to post-translocational levels, which remains to be fully elucidated in many cases.
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Affiliation(s)
- Valentin Ageorges
- Université Clermont Auvergne, INRAE, MEDiS, F-63000 Clermont-Ferrand, France
| | - Ricardo Monteiro
- Université Clermont Auvergne, INRAE, MEDiS, F-63000 Clermont-Ferrand, France.,GSK, Via Fiorentina 1, 53100 Siena, Italy
| | - Sabine Leroy
- Université Clermont Auvergne, INRAE, MEDiS, F-63000 Clermont-Ferrand, France
| | - Catherine M Burgess
- Food Safety Department, Teagasc Food Research Centre, Ashtown, Dublin 15, Ireland
| | | | - Frédérique Chaucheyras-Durand
- Université Clermont Auvergne, INRAE, MEDiS, F-63000 Clermont-Ferrand, France.,Lallemand Animal Nutrition SAS, F-31702 Blagnac Cedex, France
| | - Mickaël Desvaux
- Université Clermont Auvergne, INRAE, MEDiS, F-63000 Clermont-Ferrand, France
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5
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Barth SA, Bauerfeind R, Berens C, Menge C. Shiga Toxin-Producing E. coli in Animals: Detection, Characterization, and Virulence Assessment. Methods Mol Biol 2021; 2291:19-86. [PMID: 33704748 DOI: 10.1007/978-1-0716-1339-9_2] [Citation(s) in RCA: 2] [Impact Index Per Article: 0.7] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/16/2022]
Abstract
Cattle and other ruminants are primary reservoirs for Shiga toxin-producing Escherichia coli (STEC) strains which have a highly variable, but unpredictable, pathogenic potential for humans. Domestic swine can carry and shed STEC, but only STEC strains producing the Shiga toxin (Stx) 2e variant and causing edema disease in piglets are considered pathogens of veterinary medical interest. In this chapter, we present general diagnostic workflows for sampling livestock animals to assess STEC prevalence, magnitude, and duration of host colonization. This is followed by detailed method protocols for STEC detection and typing at genetic and phenotypic levels to assess the relative virulence exerted by the strains.
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Affiliation(s)
- Stefanie A Barth
- Friedrich-Loeffler-Institut/Federal Research Institute for Animal Health, Institute of Molecular Pathogenesis, Jena, Germany
| | - Rolf Bauerfeind
- Institute for Hygiene and Infectious Diseases of Animals, Justus Liebig University Gießen, Gießen, Germany
| | - Christian Berens
- Friedrich-Loeffler-Institut/Federal Research Institute for Animal Health, Institute of Molecular Pathogenesis, Jena, Germany
| | - Christian Menge
- Friedrich-Loeffler-Institut/Federal Research Institute for Animal Health, Institute of Molecular Pathogenesis, Jena, Germany.
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6
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Trautmann A, Schleicher L, Deusch S, Gätgens J, Steuber J, Seifert J. Short-Chain Fatty Acids Modulate Metabolic Pathways and Membrane Lipids in Prevotella bryantii B 14. Proteomes 2020; 8:proteomes8040028. [PMID: 33081314 PMCID: PMC7709123 DOI: 10.3390/proteomes8040028] [Citation(s) in RCA: 6] [Impact Index Per Article: 1.5] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/22/2020] [Revised: 10/12/2020] [Accepted: 10/13/2020] [Indexed: 12/26/2022] Open
Abstract
Short-chain fatty acids (SCFAs) are bacterial products that are known to be used as energy sources in eukaryotic hosts, whereas their role in the metabolism of intestinal microbes is rarely explored. In the present study, acetic, propionic, butyric, isobutyric, valeric, and isovaleric acid, respectively, were added to a newly defined medium containing Prevotella bryantii B14 cells. After 8 h and 24 h, optical density, pH and SCFA concentrations were measured. Long-chain fatty acid (LCFA) profiles of the bacterial cells were analyzed via gas chromatography-time of flight-mass spectrometry (GC-ToF MS) and proteins were quantified using a mass spectrometry-based, label-free approach. Cultures supplemented with single SCFAs revealed different growth behavior. Structural features of the respective SCFAs were identified in the LCFA profiles, which suggests incorporation into the bacterial membranes. The proteomes of cultures supplemented with acetic and valeric acid differed by an increased abundance of outer membrane proteins. The proteome of the isovaleric acid supplementation showed an increase of proteins in the amino acid metabolism. Our findings indicate a possible interaction between SCFAs, the lipid membrane composition, the abundance of outer membrane proteins, and a modulation of branched chain amino acid biosynthesis by isovaleric acid.
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Affiliation(s)
- Andrej Trautmann
- Institute of Animal Science, University of Hohenheim, 70599 Stuttgart, Germany; (A.T.); (S.D.)
| | - Lena Schleicher
- Institute of Biology, University of Hohenheim, 70599 Stuttgart, Germany; (L.S.); (J.S.)
| | - Simon Deusch
- Institute of Animal Science, University of Hohenheim, 70599 Stuttgart, Germany; (A.T.); (S.D.)
| | - Jochem Gätgens
- Institute of Bio- and Geosciences, IBG-1: Biotechnology, Forschungszentrum Jülich, 52425 Jülich, Germany;
| | - Julia Steuber
- Institute of Biology, University of Hohenheim, 70599 Stuttgart, Germany; (L.S.); (J.S.)
| | - Jana Seifert
- Institute of Animal Science, University of Hohenheim, 70599 Stuttgart, Germany; (A.T.); (S.D.)
- Correspondence:
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7
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Roussel C, De Paepe K, Galia W, De Bodt J, Chalancon S, Leriche F, Ballet N, Denis S, Alric M, Van de Wiele T, Blanquet-Diot S. Spatial and temporal modulation of enterotoxigenic E. coli H10407 pathogenesis and interplay with microbiota in human gut models. BMC Biol 2020; 18:141. [PMID: 33054775 PMCID: PMC7559199 DOI: 10.1186/s12915-020-00860-x] [Citation(s) in RCA: 15] [Impact Index Per Article: 3.8] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/07/2020] [Accepted: 08/31/2020] [Indexed: 01/09/2023] Open
Abstract
BACKGROUND Enterotoxigenic Escherichia coli (ETEC) substantially contributes to the burden of diarrheal illnesses in developing countries. With the use of complementary in vitro models of the human digestive environment, TNO gastrointestinal model (TIM-1), and Mucosal Simulator of the Human Intestinal Microbial Ecosystem (M-SHIME), we provided the first detailed report on the spatial-temporal modulation of ETEC H10407 survival, virulence, and its interplay with gut microbiota. These systems integrate the main physicochemical parameters of the human upper digestion (TIM-1) and simulate the ileum vs ascending colon microbial communities and luminal vs mucosal microenvironments, captured from six fecal donors (M-SHIME). RESULTS A loss of ETEC viability was noticed upon gastric digestion, while a growth renewal was found at the end of jejunal and ileal digestion. The remarkable ETEC mucosal attachment helped to maintain luminal concentrations above 6 log10 mL-1 in the ileum and ascending colon up to 5 days post-infection. Seven ETEC virulence genes were monitored. Most of them were switched on in the stomach and switched off in the TIM-1 ileal effluents and in a late post-infectious stage in the M-SHIME ascending colon. No heat-labile enterotoxin production was measured in the stomach in contrast to the ileum and ascending colon. Using 16S rRNA gene-based amplicon sequencing, ETEC infection modulated the microbial community structure of the ileum mucus and ascending colon lumen. CONCLUSIONS This study provides a better understanding of the interplay between ETEC and gastrointestinal cues and may serve to complete knowledge on ETEC pathogenesis and inspire novel prophylactic strategies for diarrheal diseases.
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Affiliation(s)
- Charlène Roussel
- Université Clermont Auvergne, UMR UCA-INRA 454 MEDIS, Microbiology Digestive Environment and Health, Clermont-Ferrand, France.,CMET, Center for Microbial Ecology and Technology, Department of Biotechnology, Faculty of Bioscience Engineering, Ghent University, Ghent, Belgium
| | - Kim De Paepe
- CMET, Center for Microbial Ecology and Technology, Department of Biotechnology, Faculty of Bioscience Engineering, Ghent University, Ghent, Belgium
| | - Wessam Galia
- UMR 5557 Microbial Ecology, Research Group on Bacterial Opportunistic Pathogens and Environment, CNRS, VetAgro Sup, Lyon, France
| | - Jana De Bodt
- CMET, Center for Microbial Ecology and Technology, Department of Biotechnology, Faculty of Bioscience Engineering, Ghent University, Ghent, Belgium
| | - Sandrine Chalancon
- Université Clermont Auvergne, UMR UCA-INRA 454 MEDIS, Microbiology Digestive Environment and Health, Clermont-Ferrand, France
| | | | - Nathalie Ballet
- Lesaffre International, Lesaffre Group, Marcq-en-Baroeul, France
| | - Sylvain Denis
- Université Clermont Auvergne, UMR UCA-INRA 454 MEDIS, Microbiology Digestive Environment and Health, Clermont-Ferrand, France
| | - Monique Alric
- Université Clermont Auvergne, UMR UCA-INRA 454 MEDIS, Microbiology Digestive Environment and Health, Clermont-Ferrand, France
| | - Tom Van de Wiele
- CMET, Center for Microbial Ecology and Technology, Department of Biotechnology, Faculty of Bioscience Engineering, Ghent University, Ghent, Belgium.
| | - Stéphanie Blanquet-Diot
- Université Clermont Auvergne, UMR UCA-INRA 454 MEDIS, Microbiology Digestive Environment and Health, Clermont-Ferrand, France.
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8
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Chen M, Fan B, Liu S, Imam KMSU, Xie Y, Wen B, Xin F. The in vitro Effect of Fibers With Different Degrees of Polymerization on Human Gut Bacteria. Front Microbiol 2020; 11:819. [PMID: 32477290 PMCID: PMC7242623 DOI: 10.3389/fmicb.2020.00819] [Citation(s) in RCA: 14] [Impact Index Per Article: 3.5] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/20/2019] [Accepted: 04/06/2020] [Indexed: 12/20/2022] Open
Abstract
Human gut bacteria contribute significantly to human health and several studies have evaluated the effects of dietary fibers on human gut bacterial ecology. However, the relationship between different degrees of fiber polymerization and human gut bacteria is unknown. Here, we analyzed three fiber substrates with different degrees of polymerization, namely carboxymethylcellulose, β-glucans, and galactooligosaccharides. To probe the in vitro influence of the degree of polymerization of the fiber on human gut bacteria, we measured the pH, air pressure, and short-chain fatty acid content of fecal fermentation supplemented with these fiber substrates, and sequenced the 16S ribosomal RNA genes of the microbial community in the fiber-treated fermentations. The butyric acid concentration was shown to decline with decreasing degree of polymerization of the fiber. Illumina Miseq sequencing indicated that the degree of polymerization might have an influence on human gut microbial diversity and abundance. Principal coordinate analysis unveiled a relationship between the degree of fiber polymerization and the gut bacterial community. Specific microbiota operational taxonomic units (OTUs) within the genera Escherichia-Shigella, Fusobacterium, and Dorea were proportional to the degree of fiber significantly, whereas OTUs within the genera Bifidobacterium, Streptococcus, and Lactobacillus were inversely correlated with the degree of polymerization. Correlation analysis between the fiber degree of polymerization and gut bacteria may demonstrate the effect of fibers on gut microbiota, and subsequently, on human health.
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Affiliation(s)
- Miao Chen
- Laboratory of Biomanufacturing and Food Engineering, Institute of Food Science and Technology, Chinese Academy of Agricultural Sciences, Beijing, China
| | - Bei Fan
- Institute of Food Science and Technology, Chinese Academy of Agricultural Sciences, Beijing, China.,Key Laboratory of Agro-products Quality and Safety Control in Storage and Transport Process, Ministry of Agriculture and Rural Affairs, Beijing, China
| | - Shujun Liu
- Laboratory of Biomanufacturing and Food Engineering, Institute of Food Science and Technology, Chinese Academy of Agricultural Sciences, Beijing, China
| | - Khandaker Md Sharif Uddin Imam
- Laboratory of Biomanufacturing and Food Engineering, Institute of Food Science and Technology, Chinese Academy of Agricultural Sciences, Beijing, China
| | - Yingying Xie
- Laboratory of Biomanufacturing and Food Engineering, Institute of Food Science and Technology, Chinese Academy of Agricultural Sciences, Beijing, China
| | - Boting Wen
- Laboratory of Biomanufacturing and Food Engineering, Institute of Food Science and Technology, Chinese Academy of Agricultural Sciences, Beijing, China
| | - Fengjiao Xin
- Laboratory of Biomanufacturing and Food Engineering, Institute of Food Science and Technology, Chinese Academy of Agricultural Sciences, Beijing, China
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9
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Eißenberger K, Moench D, Drissner D, Weiss A, Schmidt H. Adherence factors of enterohemorrhagic Escherichia coli O157:H7 strain Sakai influence its uptake into the roots of Valerianella locusta grown in soil. Food Microbiol 2018; 76:245-256. [PMID: 30166148 DOI: 10.1016/j.fm.2018.05.016] [Citation(s) in RCA: 11] [Impact Index Per Article: 1.8] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/19/2017] [Revised: 04/27/2018] [Accepted: 05/30/2018] [Indexed: 02/06/2023]
Abstract
Increasing numbers of outbreaks caused by enterohemorrhagic Escherichia coli (EHEC) are associated with the consumption of contaminated fresh produce. The contamination of the plants may occur directly on the field via irrigation water, surface water, manure or fecal contamination. Suggesting a low infectious dose of 10 to 102 cells, internalization of EHEC into plant tissue presents a serious public health threat. Therefore, the ability of EHEC O157:H7 strain Sakai to adhere to and internalize into root tissues of the lamb's lettuce Valerianella locusta was investigated under the environmental conditions of a greenhouse. Moreover, the influence of the two adherence and colonization associated genes hcpA and iha was surveyed regarding their role for attachment and invasion. Upon soil contamination, the number of root-internalized cells of EHEC O157:H7 strain Sakai exceeded 102 cfu/g roots. Deletion of one or both of the adherence factor genes did not alter the overall attachment of EHEC O157:H7 strain Sakai to the roots, but significantly reduced the numbers of internalized bacteria by a factor of between 10 and 30, indicating their importance for invasion of EHEC O157:H7 strain Sakai into plant roots. This study identified intrinsic bacterial factors that play a crucial role during the internalization of EHEC O157:H7 strain Sakai into the roots of Valerianella locusta grown under the growth conditions in a greenhouse.
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Affiliation(s)
- Kristina Eißenberger
- Institute of Food Science and Biotechnology, Department of Food Microbiology and Hygiene, University of Hohenheim, Germany
| | - Doris Moench
- Institute of Food Science and Biotechnology, Department of Food Microbiology and Hygiene, University of Hohenheim, Germany
| | - David Drissner
- Microbiology of Plant Foods, Agroscope, Waedenswil, Switzerland; Swiss Federal Institute for Forest, Snow, and Landscape Research WSL, Birmensdorf, Switzerland
| | - Agnes Weiss
- Institute of Food Science and Biotechnology, Department of Food Microbiology and Hygiene, University of Hohenheim, Germany
| | - Herbert Schmidt
- Institute of Food Science and Biotechnology, Department of Food Microbiology and Hygiene, University of Hohenheim, Germany.
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10
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Modulation of Enterohaemorrhagic Escherichia coli Survival and Virulence in the Human Gastrointestinal Tract. Microorganisms 2018; 6:microorganisms6040115. [PMID: 30463258 PMCID: PMC6313751 DOI: 10.3390/microorganisms6040115] [Citation(s) in RCA: 29] [Impact Index Per Article: 4.8] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/03/2018] [Revised: 11/16/2018] [Accepted: 11/18/2018] [Indexed: 01/05/2023] Open
Abstract
Enterohaemorrhagic Escherichia coli (EHEC) is a major foodborne pathogen responsible for human diseases ranging from diarrhoea to life-threatening complications. Survival of the pathogen and modulation of virulence gene expression along the human gastrointestinal tract (GIT) are key features in bacterial pathogenesis, but remain poorly described, due to a paucity of relevant model systems. This review will provide an overview of the in vitro and in vivo studies investigating the effect of abiotic (e.g., gastric acid, bile, low oxygen concentration or fluid shear) and biotic (e.g., gut microbiota, short chain fatty acids or host hormones) parameters of the human gut on EHEC survival and/or virulence (especially in relation with motility, adhesion and toxin production). Despite their relevance, these studies display important limitations considering the complexity of the human digestive environment. These include the evaluation of only one single digestive parameter at a time, lack of dynamic flux and compartmentalization, and the absence of a complex human gut microbiota. In a last part of the review, we will discuss how dynamic multi-compartmental in vitro models of the human gut represent a novel platform for elucidating spatial and temporal modulation of EHEC survival and virulence along the GIT, and provide new insights into EHEC pathogenesis.
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11
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Rossi E, Cimdins A, Lüthje P, Brauner A, Sjöling Å, Landini P, Römling U. "It's a gut feeling" - Escherichia coli biofilm formation in the gastrointestinal tract environment. Crit Rev Microbiol 2017; 44:1-30. [PMID: 28485690 DOI: 10.1080/1040841x.2017.1303660] [Citation(s) in RCA: 57] [Impact Index Per Article: 8.1] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/22/2022]
Abstract
Escherichia coli can commonly be found, either as a commensal, probiotic or a pathogen, in the human gastrointestinal (GI) tract. Biofilm formation and its regulation is surprisingly variable, although distinct regulatory pattern of red, dry and rough (rdar) biofilm formation arise in certain pathovars and even clones. In the GI tract, environmental conditions, signals from the host and from commensal bacteria contribute to shape E. coli biofilm formation within the multi-faceted multicellular communities in a complex and integrated fashion. Although some major regulatory networks, adhesion factors and extracellular matrix components constituting E. coli biofilms have been recognized, these processes have mainly been characterized in vitro and in the context of interaction of E. coli strains with intestinal epithelial cells. However, direct observation of E. coli cells in situ, and the vast number of genes encoding surface appendages on the core or accessory genome of E. coli suggests the complexity of the biofilm process to be far from being fully understood. In this review, we summarize biofilm formation mechanisms of commensal, probiotic and pathogenic E. coli in the context of the gastrointestinal tract.
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Affiliation(s)
- Elio Rossi
- a Department of Biosciences , Università degli Studi di Milano , Milan , Italy.,b Novo Nordisk Center for Biosustainabiliy , Technical University of Denmark , Kgs. Lyngby , Denmark
| | - Annika Cimdins
- c Department of Microbiology, Tumor and Cell Biology (MTC) , Karolinska Institutet , Stockholm , Sweden.,d Institute of Hygiene, University of Münster , Münster , Germany
| | - Petra Lüthje
- c Department of Microbiology, Tumor and Cell Biology (MTC) , Karolinska Institutet , Stockholm , Sweden.,e Division of Clinical Microbiology, Department of Laboratory Medicine , Karolinska Institutet and Karolinska University Hospital Huddinge , Stockholm , Sweden
| | - Annelie Brauner
- c Department of Microbiology, Tumor and Cell Biology (MTC) , Karolinska Institutet , Stockholm , Sweden
| | - Åsa Sjöling
- c Department of Microbiology, Tumor and Cell Biology (MTC) , Karolinska Institutet , Stockholm , Sweden
| | - Paolo Landini
- a Department of Biosciences , Università degli Studi di Milano , Milan , Italy
| | - Ute Römling
- c Department of Microbiology, Tumor and Cell Biology (MTC) , Karolinska Institutet , Stockholm , Sweden
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12
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Bernal V, Castaño-Cerezo S, Cánovas M. Acetate metabolism regulation in Escherichia coli: carbon overflow, pathogenicity, and beyond. Appl Microbiol Biotechnol 2016; 100:8985-9001. [DOI: 10.1007/s00253-016-7832-x] [Citation(s) in RCA: 54] [Impact Index Per Article: 6.8] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/21/2016] [Revised: 08/22/2016] [Accepted: 08/24/2016] [Indexed: 12/11/2022]
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13
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Lackraj T, Kim JI, Tran SL, Barnett Foster DE. Differential modulation of flagella expression in enterohaemorrhagic Escherichia coli O157: H7 by intestinal short-chain fatty acid mixes. MICROBIOLOGY-SGM 2016; 162:1761-1772. [PMID: 27535670 DOI: 10.1099/mic.0.000357] [Citation(s) in RCA: 17] [Impact Index Per Article: 2.1] [Reference Citation Analysis] [Abstract] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 12/31/2022]
Abstract
During passage through the gastrointestinal tract, enterohaemorrhagic Escherichia coli (EHEC) encounters numerous stresses, each producing unique antimicrobial conditions. Beyond surviving these stresses, EHEC may also use them as cues about the local microenvironment to modulate its virulence. Of particular interest is how exposure to changing concentrations of short-chain fatty acids (SCFAs) associated with passage through the small and large intestines affects EHEC virulence, as well as flagella expression and motility specifically. In this study, we investigate the impact of exposure to SCFA mixes simulating concentrations and compositions within the small and large intestines on EHEC flagella expression and function. Using a combination of DNA microarray, quantitative real-time PCR, immunoblot analysis, flow cytometry and motility assays, we show that there is a marked, significant upregulation of flagellar genes, the flagellar protein, FliC, and motility when EHEC is exposed to SCFA mixes representative of the small intestine. By contrast, when EHEC is exposed to SCFA mixes representative of the large intestine, there is a significant downregulation of flagellar genes, FliC and motility. Our results demonstrate that EHEC modulates flagella expression and motility in response to SCFAs, with differential responses associated with SCFA mixes typical of the small and large intestines. This research contributes to our understanding of how EHEC senses and responds to host environmental signals and the mechanisms it uses to successfully infect the human host. Significantly, it also suggests that EHEC is using this key gastrointestinal chemical signpost to cue changes in flagella expression and motility in different locations within the host intestinal tract.
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Affiliation(s)
- Tracy Lackraj
- Department of Chemistry and Biology, Ryerson University, Toronto, ON, Canada
| | - Jee In Kim
- Department of Chemistry and Biology, Ryerson University, Toronto, ON, Canada
| | - Seav-Ly Tran
- Department of Chemistry and Biology, Ryerson University, Toronto, ON, Canada
| | - Debora E Barnett Foster
- Faculty of Dentistry, University of Toronto, Toronto, ON, Canada.,Department of Chemistry and Biology, Ryerson University, Toronto, ON, Canada.,Program for Molecular Structure and Function, Research Institute, Hospital for Sick Children, Toronto, ON, Canada
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14
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Monteiro R, Ageorges V, Rojas-Lopez M, Schmidt H, Weiss A, Bertin Y, Forano E, Jubelin G, Henderson IR, Livrelli V, Gobert AP, Rosini R, Soriani M, Desvaux M. A secretome view of colonisation factors in Shiga toxin-encodingEscherichia coli(STEC): from enterohaemorrhagicE. coli(EHEC) to related enteropathotypes. FEMS Microbiol Lett 2016; 363:fnw179. [DOI: 10.1093/femsle/fnw179] [Citation(s) in RCA: 23] [Impact Index Per Article: 2.9] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Accepted: 07/18/2016] [Indexed: 12/25/2022] Open
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15
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Escherichia coli O104:H4 Pathogenesis: an Enteroaggregative E. coli/Shiga Toxin-Producing E. coli Explosive Cocktail of High Virulence. Microbiol Spectr 2016; 2. [PMID: 26104460 DOI: 10.1128/microbiolspec.ehec-0008-2013] [Citation(s) in RCA: 56] [Impact Index Per Article: 7.0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/25/2022] Open
Abstract
A major outbreak caused by Escherichia coli of serotype O104:H4 spread throughout Europe in 2011. This large outbreak was caused by an unusual strain that is most similar to enteroaggregative E. coli (EAEC) of serotype O104:H4. A significant difference, however, is the presence of a prophage encoding the Shiga toxin, which is characteristic of enterohemorrhagic E. coli (EHEC) strains. This combination of genomic features, associating characteristics from both EAEC and EHEC, represents a new pathotype. The 2011 E. coli O104:H4 outbreak of hemorrhagic diarrhea in Germany is an example of the explosive cocktail of high virulence and resistance that can emerge in this species. A total of 46 deaths, 782 cases of hemolytic-uremic syndrome, and 3,128 cases of acute gastroenteritis were attributed to this new clone of EAEC/EHEC. In addition, recent identification in France of similar O104:H4 clones exhibiting the same virulence factors suggests that the EHEC O104:H4 pathogen has become endemically established in Europe after the end of the outbreak. EAEC strains of serotype O104:H4 contain a large set of virulence-associated genes regulated by the AggR transcription factor. They include, among other factors, the pAA plasmid genes encoding the aggregative adherence fimbriae, which anchor the bacterium to the intestinal mucosa (stacked-brick adherence pattern on epithelial cells). Furthermore, sequencing studies showed that horizontal genetic exchange allowed for the emergence of the highly virulent Shiga toxin-producing EAEC O104:H4 strain that caused the German outbreak. This article discusses the role these virulence factors could have in EAEC/EHEC O104:H4 pathogenesis.
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Abstract
Enterohemorrhagic Escherichia coli (EHEC) is a highly pathogenic bacterial strain capable of causing watery or bloody diarrhea, the latter termed hemorrhagic colitis, and hemolytic-uremic syndrome (HUS). HUS is defined as the simultaneous development of non-immune hemolytic anemia, thrombocytopenia, and acute renal failure. The mechanism by which EHEC bacteria colonize and cause severe colitis, followed by renal failure with activated blood cells, as well as neurological symptoms, involves the interaction of bacterial virulence factors and specific pathogen-associated molecular patterns with host cells as well as the host response. The innate immune host response comprises the release of antimicrobial peptides as well as cytokines and chemokines in addition to activation and/or injury to leukocytes, platelets, and erythrocytes and activation of the complement system. Some of the bacterial interactions with the host may be protective in nature, but, when excessive, contribute to extensive tissue injury, inflammation, and thrombosis, effects that may worsen the clinical outcome of EHEC infection. This article describes aspects of the host response occurring during EHEC infection and their effects on specific organs.
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17
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Thévenot J, Cordonnier C, Rougeron A, Le Goff O, Nguyen HTT, Denis S, Alric M, Livrelli V, Blanquet-Diot S. Enterohemorrhagic Escherichia coli infection has donor-dependent effect on human gut microbiota and may be antagonized by probiotic yeast during interaction with Peyer's patches. Appl Microbiol Biotechnol 2015; 99:9097-110. [PMID: 26084888 DOI: 10.1007/s00253-015-6704-0] [Citation(s) in RCA: 33] [Impact Index Per Article: 3.7] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/27/2015] [Revised: 05/13/2015] [Accepted: 05/17/2015] [Indexed: 01/05/2023]
Abstract
Enterohemorrhagic Escherichia coli (EHEC) are major food-borne pathogens responsible for serious infections ranging from mild diarrhea to hemorrhagic colitis and life-threatening complications. Shiga toxins (Stxs) are the main virulence factor of EHEC. The antagonistic effect of a prophylactic treatment with the probiotic strain Saccharomyces cerevisiae against EHEC O157:H7 was investigated using complementary in vitro human colonic model and in vivo murine ileal loop assays. In vitro, the probiotic treatment had no effect on O157:H7 survival but favorably influenced gut microbiota activity through modulation of short-chain fatty acid production, increasing acetate production and decreasing that of butyrate. Both pathogen and probiotic strains had individual-dependent effects on human gut microbiota. For the first time, stx expression was followed in human colonic environment: at 9 and 12 h post EHEC infection, probiotic treatment significantly decreased stx mRNA levels. Besides, in murine ileal loops, the probiotic yeast specifically exerted a trophic effect on intestinal mucosa and inhibited O157:H7 interactions with Peyer's patches and subsequent hemorrhagic lesions. Taken together, the results suggest that S. cerevisiae may be useful in the fight against EHEC infection and that host associated factors such as microbiota could influence clinical evolution of EHEC infection and the effectiveness of probiotics.
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Affiliation(s)
- J Thévenot
- Centre de Recherche en Nutrition Humaine Auvergne, EA 4678 CIDAM, Conception Ingénierie et Développement de l'Aliment et du Médicament, Clermont Université, Université d'Auvergne, Clermont-Ferrand, France.,Centre de Recherche en Nutrition Humaine Auvergne, M2iSH, Microbes, Intestin, Inflammation et Susceptibilité de l'Hôte UMR INSERM / Université d'Auvergne U1071 USC-INRA 2018, Clermont Université, Université d'Auvergne, Clermont-Ferrand, France
| | - C Cordonnier
- Centre de Recherche en Nutrition Humaine Auvergne, EA 4678 CIDAM, Conception Ingénierie et Développement de l'Aliment et du Médicament, Clermont Université, Université d'Auvergne, Clermont-Ferrand, France.,Centre de Recherche en Nutrition Humaine Auvergne, M2iSH, Microbes, Intestin, Inflammation et Susceptibilité de l'Hôte UMR INSERM / Université d'Auvergne U1071 USC-INRA 2018, Clermont Université, Université d'Auvergne, Clermont-Ferrand, France
| | - A Rougeron
- Centre de Recherche en Nutrition Humaine Auvergne, M2iSH, Microbes, Intestin, Inflammation et Susceptibilité de l'Hôte UMR INSERM / Université d'Auvergne U1071 USC-INRA 2018, Clermont Université, Université d'Auvergne, Clermont-Ferrand, France
| | - O Le Goff
- Centre de Recherche en Nutrition Humaine Auvergne, EA 4678 CIDAM, Conception Ingénierie et Développement de l'Aliment et du Médicament, Clermont Université, Université d'Auvergne, Clermont-Ferrand, France
| | - H T T Nguyen
- Centre de Recherche en Nutrition Humaine Auvergne, M2iSH, Microbes, Intestin, Inflammation et Susceptibilité de l'Hôte UMR INSERM / Université d'Auvergne U1071 USC-INRA 2018, Clermont Université, Université d'Auvergne, Clermont-Ferrand, France
| | - S Denis
- Centre de Recherche en Nutrition Humaine Auvergne, EA 4678 CIDAM, Conception Ingénierie et Développement de l'Aliment et du Médicament, Clermont Université, Université d'Auvergne, Clermont-Ferrand, France
| | - M Alric
- Centre de Recherche en Nutrition Humaine Auvergne, EA 4678 CIDAM, Conception Ingénierie et Développement de l'Aliment et du Médicament, Clermont Université, Université d'Auvergne, Clermont-Ferrand, France
| | - V Livrelli
- Centre de Recherche en Nutrition Humaine Auvergne, M2iSH, Microbes, Intestin, Inflammation et Susceptibilité de l'Hôte UMR INSERM / Université d'Auvergne U1071 USC-INRA 2018, Clermont Université, Université d'Auvergne, Clermont-Ferrand, France.,Service de Bactériologie, CHU Clermont-Ferrand, Clermont-Ferrand, France
| | - S Blanquet-Diot
- Centre de Recherche en Nutrition Humaine Auvergne, EA 4678 CIDAM, Conception Ingénierie et Développement de l'Aliment et du Médicament, Clermont Université, Université d'Auvergne, Clermont-Ferrand, France.
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18
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Chemical communication in the gut: Effects of microbiota-generated metabolites on gastrointestinal bacterial pathogens. Anaerobe 2015; 34:106-15. [PMID: 25958185 DOI: 10.1016/j.anaerobe.2015.05.002] [Citation(s) in RCA: 77] [Impact Index Per Article: 8.6] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/27/2015] [Revised: 04/24/2015] [Accepted: 05/04/2015] [Indexed: 01/27/2023]
Abstract
Gastrointestinal pathogens must overcome many obstacles in order to successfully colonize a host, not the least of which is the presence of the gut microbiota, the trillions of commensal microorganisms inhabiting mammals' digestive tracts, and their products. It is well established that a healthy gut microbiota provides its host with protection from numerous pathogens, including Salmonella species, Clostridium difficile, diarrheagenic Escherichia coli, and Vibrio cholerae. Conversely, pathogenic bacteria have evolved mechanisms to establish an infection and thrive in the face of fierce competition from the microbiota for space and nutrients. Here, we review the evidence that gut microbiota-generated metabolites play a key role in determining the outcome of infection by bacterial pathogens. By consuming and transforming dietary and host-produced metabolites, as well as secreting primary and secondary metabolites of their own, the microbiota define the chemical environment of the gut and often determine specific host responses. Although most gut microbiota-produced metabolites are currently uncharacterized, several well-studied molecules made or modified by the microbiota are known to affect the growth and virulence of pathogens, including short-chain fatty acids, succinate, mucin O-glycans, molecular hydrogen, secondary bile acids, and the AI-2 quorum sensing autoinducer. We also discuss challenges and possible approaches to further study of the chemical interplay between microbiota and gastrointestinal pathogens.
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19
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Abstract
Adhesins are a group of proteins in enterohemorrhagic Escherichia coli (EHEC) that are involved in the attachment or colonization of this pathogen to abiotic (plastic or steel) and biological surfaces, such as those found in bovine and human intestines. This review provides the most up-to-date information on these essential adhesion factors, summarizing important historical discoveries and analyzing the current and future state of this research. In doing so, the proteins intimin and Tir are discussed in depth, especially regarding their role in the development of attaching and effacing lesions and in EHEC virulence. Further, a series of fimbrial proteins (Lpf1, Lpf2, curli, ECP, F9, ELF, Sfp, HCP, and type 1 fimbriae) are also described, emphasizing their various contributions to adherence and colonization of different surfaces and their potential use as genetic markers in detection and classification of different EHEC serotypes. This review also discusses the role of several autotransporter proteins (EhaA-D, EspP, Saa and Sab, and Cah), as well as other proteins associated with adherence, such as flagella, EibG, Iha, and OmpA. While these proteins have all been studied to varying degrees, all of the adhesins summarized in this chapter have been linked to different stages of the EHEC life cycle, making them good targets for the development of more effective diagnostics and therapeutics.
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Affiliation(s)
- Brian D. McWilliams
- Department of Microbiology and Immunology, University of Texas Medical Branch, Galveston, Texas, 77555. USA
| | - Alfredo G. Torres
- Department of Microbiology and Immunology, University of Texas Medical Branch, Galveston, Texas, 77555. USA
- Department of Pathology and Sealy Center for Vaccine Development, University of Texas Medical Branch, Galveston, Texas, 77555. USA
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20
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Kortman GAM, Raffatellu M, Swinkels DW, Tjalsma H. Nutritional iron turned inside out: intestinal stress from a gut microbial perspective. FEMS Microbiol Rev 2014; 38:1202-34. [PMID: 25205464 DOI: 10.1111/1574-6976.12086] [Citation(s) in RCA: 168] [Impact Index Per Article: 16.8] [Reference Citation Analysis] [Abstract] [Key Words] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/28/2014] [Revised: 08/27/2014] [Accepted: 08/29/2014] [Indexed: 12/16/2022] Open
Abstract
Iron is abundantly present on earth, essential for most microorganisms and crucial for human health. Human iron deficiency that is nevertheless highly prevalent in developing regions of the world can be effectively treated by oral iron administration. Accumulating evidence indicates that excess of unabsorbed iron that enters the colonic lumen causes unwanted side effects at the intestinal host-microbiota interface. The chemical properties of iron, the luminal environment and host iron withdrawal mechanisms, especially during inflammation, can turn the intestine in a rather stressful milieu. Certain pathogenic enteric bacteria can, however, deal with this stress at the expense of other members of the gut microbiota, while their virulence also seems to be stimulated in an iron-rich intestinal environment. This review covers the multifaceted aspects of nutritional iron stress with respect to growth, composition, metabolism and pathogenicity of the gut microbiota in relation to human health. We aim to present an unpreceded view on the dynamic effects and impact of oral iron administration on intestinal host-microbiota interactions to provide leads for future research and other applications.
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Affiliation(s)
- Guus A M Kortman
- Department of Laboratory Medicine, The Radboud Institute for Molecular Life Sciences (RIMLS) of the Radboud University Medical Center, Nijmegen, The Netherlands
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21
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Yurist-Doutsch S, Arrieta MC, Vogt SL, Finlay BB. Gastrointestinal microbiota-mediated control of enteric pathogens. Annu Rev Genet 2014; 48:361-82. [PMID: 25251855 DOI: 10.1146/annurev-genet-120213-092421] [Citation(s) in RCA: 45] [Impact Index Per Article: 4.5] [Reference Citation Analysis] [Abstract] [Key Words] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/09/2022]
Abstract
The gastrointestinal (GI) microbiota is a complex community of microorganisms residing within the mammalian gastrointestinal tract. The GI microbiota is vital to the development of the host immune system and plays a crucial role in human health and disease. The composition of the GI microbiota differs immensely among individuals yet specific shifts in composition and diversity have been linked to inflammatory bowel disease, obesity, atopy, and susceptibility to infection. In this review, we describe the GI microbiota and its role in enteric diseases caused by pathogenic Escherichia coli, Salmonella enterica, and Clostridium difficile. We discuss the central role of the GI microbiota in protective immunity, resistance to enteric pathogens, and resolution of enteric colitis.
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Affiliation(s)
- Sophie Yurist-Doutsch
- Michael Smith Laboratories, The University of British Columbia, Vancouver, British Columbia, Canada, V6T 1Z4; , , ,
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22
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Tan J, McKenzie C, Potamitis M, Thorburn AN, Mackay CR, Macia L. The role of short-chain fatty acids in health and disease. Adv Immunol 2014; 121:91-119. [PMID: 24388214 DOI: 10.1016/b978-0-12-800100-4.00003-9] [Citation(s) in RCA: 1386] [Impact Index Per Article: 138.6] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/16/2022]
Abstract
There is now an abundance of evidence to show that short-chain fatty acids (SCFAs) play an important role in the maintenance of health and the development of disease. SCFAs are a subset of fatty acids that are produced by the gut microbiota during the fermentation of partially and nondigestible polysaccharides. The highest levels of SCFAs are found in the proximal colon, where they are used locally by enterocytes or transported across the gut epithelium into the bloodstream. Two major SCFA signaling mechanisms have been identified, inhibition of histone deacetylases (HDACs) and activation of G-protein-coupled receptors (GPCRs). Since HDACs regulate gene expression, inhibition of HDACs has a vast array of downstream consequences. Our understanding of SCFA-mediated inhibition of HDACs is still in its infancy. GPCRs, particularly GPR43, GPR41, and GPR109A, have been identified as receptors for SCFAs. Studies have implicated a major role for these GPCRs in the regulation of metabolism, inflammation, and disease. SCFAs have been shown to alter chemotaxis and phagocytosis; induce reactive oxygen species (ROS); change cell proliferation and function; have anti-inflammatory, antitumorigenic, and antimicrobial effects; and alter gut integrity. These findings highlight the role of SCFAs as a major player in maintenance of gut and immune homeostasis. Given the vast effects of SCFAs, and that their levels are regulated by diet, they provide a new basis to explain the increased prevalence of inflammatory disease in Westernized countries, as highlighted in this chapter.
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Affiliation(s)
- Jian Tan
- Department of Immunology, Monash University, Clayton, Victoria, Australia
| | - Craig McKenzie
- Department of Immunology, Monash University, Clayton, Victoria, Australia
| | - Maria Potamitis
- Department of Immunology, Monash University, Clayton, Victoria, Australia
| | - Alison N Thorburn
- Department of Immunology, Monash University, Clayton, Victoria, Australia
| | - Charles R Mackay
- Department of Immunology, Monash University, Clayton, Victoria, Australia.
| | - Laurence Macia
- Department of Immunology, Monash University, Clayton, Victoria, Australia.
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23
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Kendall MM, Sperandio V. Cell-to-Cell Signaling in Escherichia coli and Salmonella. EcoSal Plus 2014; 6:10.1128/ecosalplus.ESP-0002-2013. [PMID: 26442936 PMCID: PMC4229655 DOI: 10.1128/ecosalplus.esp-0002-2013] [Citation(s) in RCA: 29] [Impact Index Per Article: 2.9] [Reference Citation Analysis] [Abstract] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/03/2014] [Indexed: 01/21/2023]
Abstract
Bacteria must be able to respond rapidly to changes in the environment to survive. One means of coordinating gene expression relies on tightly regulated and complex signaling systems. One of the first signaling systems that was described in detail is quorum sensing (QS). During QS, a bacterial cell produces and secretes a signaling molecule called an autoinducer (AI). As the density of the bacterial population increases, so does the concentration of secreted AI molecules, thereby allowing a bacterial species to coordinate gene expression based on population density. Subsequent studies have demonstrated that bacteria are also able to detect signal molecules produced by other species of bacteria as well as hormones produced by their mammalian hosts. This type of signaling interaction has been termed cell-to-cell signaling because it does not rely on a threshold concentration of bacterial cells. This review discusses the three main types of cell-to-cell signaling mechanisms used by Escherichia coli and Salmonella: the LuxR process, in which E. coli and Salmonella detect signals produced by other species of bacteria; the LuxS/AI-2 system, in which E. coli and Salmonella participate in intra- and interspecies signaling; and the AI-3/epinephrine/norepinephrine system, in which E. coli and Salmonella recognize self-produced AI, signal produced by other microbes, and/or the human stress hormones epinephrine and/or norepinephrine.
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Affiliation(s)
- Melissa M. Kendall
- Department of Microbiology, University of Texas Southwestern Medical Center, 5323 Harry Hines Blvd., Dallas, TX, 75390, USA
| | - Vanessa Sperandio
- Department of Microbiology, University of Texas Southwestern Medical Center, 5323 Harry Hines Blvd., Dallas, TX, 75390, USA
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24
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Barnett Foster D. Modulation of the enterohemorrhagic E. coli virulence program through the human gastrointestinal tract. Virulence 2013; 4:315-23. [PMID: 23552827 PMCID: PMC3710334 DOI: 10.4161/viru.24318] [Citation(s) in RCA: 50] [Impact Index Per Article: 4.5] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/22/2022] Open
Abstract
Enteric pathogens must not only survive passage through the gastrointestinal tract but must also coordinate expression of virulence determinants in response to localized microenvironments with the host. Enterohemorrhagic Escherichia coli (EHEC), a serious food and waterborne human pathogen, is well equipped with an arsenal of molecular factors that allows it to survive passage through the gastrointestinal tract and successfully colonize the large intestine. This review will explore how EHEC responds to various environmental cues associated with particular microenvironments within the host and how it employs these cues to modulate virulence factor expression, with a view to developing a conceptual framework for understanding modulation of EHEC’s virulence program in response to the host. In vitro studies offer significant insights into the role of individual environmental cues but in vivo studies using animal models as well as data from natural infections will ultimately provide a more comprehensive picture of the highly regulated virulence program of this pathogen.
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Affiliation(s)
- Debora Barnett Foster
- Department of Chemistry and Biology, Faculty of Science, Ryerson University, Toronto, ONT, Canada.
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25
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Lehti TA, Bauchart P, Kukkonen M, Dobrindt U, Korhonen TK, Westerlund-Wikström B. Phylogenetic group-associated differences in regulation of the common colonization factor Mat fimbria in Escherichia coli. Mol Microbiol 2013; 87:1200-22. [PMID: 23347101 DOI: 10.1111/mmi.12161] [Citation(s) in RCA: 23] [Impact Index Per Article: 2.1] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Accepted: 01/17/2013] [Indexed: 11/28/2022]
Abstract
Heterogeneity of cell population is a key component behind the evolutionary success of Escherichia coli. The heterogeneity supports species adaptation and mainly results from lateral gene transfer. Adaptation may also involve genomic alterations that affect regulation of conserved genes. Here we analysed regulation of the mat (or ecp) genes that encode a conserved fimbrial adhesin of E. coli. We found that the differential and temperature-sensitive expression control of the mat operon is dependent on mat promoter polymorphism and closely linked to phylogenetic grouping of E. coli. In the mat promoter lineage favouring fimbriae expression, the mat operon-encoded regulator MatA forms a positive feedback loop that overcomes the repression by H-NS and stabilizes the fimbrillin mRNA under low growth temperature, acidic pH or elevated levels of acetate. The study exemplifies phylogenetic group-associated expression of a highly common surface organelle in E. coli.
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Affiliation(s)
- Timo A Lehti
- Division of General Microbiology, Department of Biosciences, FI-00014 University of Helsinki, Helsinki, Finland
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26
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Sun Y, O'Riordan MXD. Regulation of bacterial pathogenesis by intestinal short-chain Fatty acids. ADVANCES IN APPLIED MICROBIOLOGY 2013; 85:93-118. [PMID: 23942149 PMCID: PMC4029053 DOI: 10.1016/b978-0-12-407672-3.00003-4] [Citation(s) in RCA: 197] [Impact Index Per Article: 17.9] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 12/13/2022]
Abstract
The human gut microbiota is inextricably linked to health and disease. One important function of the commensal organisms living in the intestine is to provide colonization resistance against invading enteric pathogens. Because of the complex nature of the interaction between the microbiota and its host, multiple mechanisms likely contribute to resistance. In this review, we dissect the biological role of short-chain fatty acids (SCFA), which are fermentation end products of the intestinal microbiota, in host-pathogen interactions. SCFA exert an extensive influence on host physiology through nutritional, regulatory, and immunomodulatory functions and can also affect bacterial fitness as a form of acid stress. Moreover, SCFA act as a signal for virulence gene regulation in common enteric pathogens. Taken together, these studies highlight the importance of the chemical environment where the biology of the host, the microbiota, and the pathogen intersects, which provides a basis for designing effective infection prevention and control.
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Affiliation(s)
- Yvonne Sun
- Department of Microbiology and Immunology, University of Michigan Medical School, Ann Arbor, Michigan, USA.
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27
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Sun Y, Wilkinson BJ, Standiford TJ, Akinbi HT, O'Riordan MXD. Fatty acids regulate stress resistance and virulence factor production for Listeria monocytogenes. J Bacteriol 2012; 194:5274-84. [PMID: 22843841 PMCID: PMC3457240 DOI: 10.1128/jb.00045-12] [Citation(s) in RCA: 78] [Impact Index Per Article: 6.5] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/11/2012] [Accepted: 07/09/2012] [Indexed: 12/15/2022] Open
Abstract
Fatty acids (FAs) are the major structural component of cellular membranes, which provide a physical and chemical barrier that insulates intracellular reactions from environmental fluctuations. The native composition of membrane FAs establishes the topological and chemical parameters for membrane-associated functions and is therefore modulated diligently by microorganisms especially in response to environmental stresses. However, the consequences of altered FA composition during host-pathogen interactions are poorly understood. The food-borne pathogen Listeria monocytogenes contains mostly saturated branched-chain FAs (BCFAs), which support growth at low pH and low temperature. In this study, we show that anteiso-BCFAs enhance bacterial resistance against phagosomal killing in macrophages. Specifically, BCFAs protect against antimicrobial peptides and peptidoglycan hydrolases, two classes of phagosome antimicrobial defense mechanisms. In addition, the production of the critical virulence factor, listeriolysin O, was compromised by FA modulation, suggesting that FAs play a key role in virulence regulation. In summary, our results emphasize the significance of FA metabolism, not only in bacterial virulence regulation but also in membrane barrier function by providing resistance against host antimicrobial stress.
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Affiliation(s)
- Yvonne Sun
- University of Michigan Medical School, Department of Microbiology and Immunology, Ann Arbor, Michigan, USA.
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28
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Variability of Escherichia coli O157 strain survival in manure-amended soil in relation to strain origin, virulence profile, and carbon nutrition profile. Appl Environ Microbiol 2011; 77:8088-96. [PMID: 21908630 DOI: 10.1128/aem.00745-11] [Citation(s) in RCA: 69] [Impact Index Per Article: 5.3] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/30/2022] Open
Abstract
The variation in manure-amended soil survival capability among 18 Escherichia coli O157 strains (8 animal, 1 food, and 9 human isolates) was studied using a single sandy soil sample and a single sample of cattle manure as the inoculum carrier. The virulence profiles of E. coli O157 strains were characterized by detection of virulence determinants (73 genes, 122 probes in duplicate) by using the Identibac E. coli genotyping DNA miniaturized microarray. Metabolic profiling was done by subjecting all strains to the Biolog phenotypic carbon microarray. Survival times (calculated as days needed to reach the detection limit using the Weibull model) ranged from 47 to 266 days (median, 120 days). Survival time was significantly higher for the group of human isolates (median, 211 days; minimum [min.], 71; maximum [max.], 266) compared to the group of animal isolates (median, 70 days; min., 47; max., 249) (P = 0.025). Although clustering of human versus animal strains was observed based on pulsed-field gel electrophoresis (PFGE) patterns, no relation between survival time and the presence of virulence genes was observed. Principal component analysis on the metabolic profiling data revealed distinct clustering of short- and long-surviving strains. The oxidization rate of propionic acid, α-ketobutyric acid, and α-hydroxybutyric acid was significantly higher for the long-surviving strains than for the short-surviving strains. The oxidative capacity of E. coli O157 strains may be regarded as a phenotypic marker for enhanced survival in manure-amended soil. The large variation observed in survival is of importance for risk assessment models.
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