1
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Liu Y, Yan Y, Yang K, Yang X, Dong P, Wu H, Luo X, Zhang Y, Zhu L. Inhibitory mechanism of Salmonella Derby biofilm formation by sub-inhibitory concentrations of clove and oregano essential oil: A global transcriptomic study. Food Control 2023. [DOI: 10.1016/j.foodcont.2023.109734] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 03/14/2023]
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2
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Zhu B, McBride JW. Alpha Enolase 1 Ubiquitination and Degradation Mediated by Ehrlichia chaffeensis TRP120 Disrupts Glycolytic Flux and Promotes Infection. Pathogens 2021; 10:962. [PMID: 34451426 PMCID: PMC8400980 DOI: 10.3390/pathogens10080962] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/25/2021] [Revised: 07/23/2021] [Accepted: 07/27/2021] [Indexed: 11/17/2022] Open
Abstract
Ehrlichia chaffeensis modulates numerous host cell processes, including gene transcription to promote infection of the mononuclear phagocyte. Modulation of these host cell processes is directed through E. chaffeensis effectors, including TRP120. We previously reported that TRP120 moonlights as a HECT E3 Ub ligase that ubiquitinates host cell transcription and fate regulators (PCGF5 and FBW7) to promote infection. In this study, we identified a novel TRP120 substrate and examined the relationship between TRP120 and α-enolase (ENO1), a metalloenzyme that catalyzes glycolytic pathway substrate dehydration. Immunofluorescence microscopy and coimmunoprecipitation demonstrated interaction between ENO1 and TRP120, and ubiquitination of ENO-1 by TRP120 was detected in vivo and in vitro. Further, ENO-1 degradation was observed during infection and was inhibited by the proteasomal inhibitor bortezomib. A direct role of TRP120 Ub ligase activity in ENO-1 degradation was demonstrated and confirmed by ectopic expression of TRP120 HECT Ub ligase catalytic site mutant. siRNA knockdown of ENO-1 coincided with increased E. chaffeensis infection and ENO-1 knockdown disrupted glycolytic flux by decreasing the levels of pyruvate and lactate that may contribute to changes in host cell metabolism that promote infection. In addition, we elucidated a functional role of TRP120 auto-ubiquitination as an activating event that facilitates the recruitment of the UbcH5 E2 ubiquitin-conjugating enzyme. This investigation further expands the repertoire of TRP120 substrates and extends the potential role of TRP120 Ub ligase in infection to include metabolic reprogramming.
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Affiliation(s)
- Bing Zhu
- Department of Pathology, University of Texas Medical Branch, Galveston, TX 77555-0609, USA;
| | - Jere W. McBride
- Department of Pathology, University of Texas Medical Branch, Galveston, TX 77555-0609, USA;
- Department of Microbiology & Immunology, University of Texas Medical Branch, Galveston, TX 77555-0609, USA
- Center for Biodefense and Emerging Infectious Diseases, University of Texas Medical Branch, Galveston, TX 77555-0609, USA
- Sealy Center for Vaccine Development, University of Texas Medical Branch, Galveston, TX 77555-0609, USA
- Institute for Human Infections and Immunity, University of Texas Medical Branch, Galveston, TX 77555-0609, USA
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3
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Zúñiga A, Solis C, Cartes C, Nourdin G, Yañez A, Romero A, Haussmann D, Figueroa J. Transcriptional analysis of metabolic and virulence genes associated with biofilm formation in Piscirickettsia salmonis strains. FEMS Microbiol Lett 2021; 367:5948097. [PMID: 33128546 DOI: 10.1093/femsle/fnaa180] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/20/2020] [Accepted: 10/29/2020] [Indexed: 12/14/2022] Open
Abstract
Piscirickettsia salmonis is a facultative intracellular bacterium that generates piscirickettsiosis affecting salmonids in Chile. The bacterium has the adaptability to survive in the marine environment under multiple stressful conditions. In this sense, this work focused on the analysis of a gene battery associated with biofilm formation under different culture conditions and on the adaptability of this biofilm to different media. The results indicated that the strains LF-89, IBM-034 and IBM-040 were strong biofilm producers, evidencing adaptability to the media by increasing the amount of biofilm through successive growths. Transcript levels of six genes described in various bacteria and P. salmonis, considered to have metabolic functions, and playing a relevant role in biofilm formation, were analyzed to evaluate bacterial functionality in the biofilm. The genes mazE-mazF, implicated in biofilm and stress, were markedly overexpressed in the biofilm condition in the three strains. For its part, gene gltA, an indicator of metabolic activity and related to virulence inhibition in Salmonella typhimurium, also seems to restrain the pathogenesis process in P. salmonis by inhibiting the expression of the virulence-associated genes liso and tcf. Finally, the expression of the glnA gene suggests the use of glutamine as an essential element for the growth of the biofilm.
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Affiliation(s)
- A Zúñiga
- Institute of Biochemistry and Microbiology, Faculty of Sciences, Universidad Austral de Chile, Valdivia, Chile
| | - C Solis
- Institute of Biochemistry and Microbiology, Faculty of Sciences, Universidad Austral de Chile, Valdivia, Chile
| | - C Cartes
- Institute of Biochemistry and Microbiology, Faculty of Sciences, Universidad Austral de Chile, Valdivia, Chile.,FONDAP Centre: Interdisciplinary Centre for Aquaculture Research (INCAR), O'Higgins 1695, Concepción, Chile
| | - G Nourdin
- FONDAP Centre: Interdisciplinary Centre for Aquaculture Research (INCAR), O'Higgins 1695, Concepción, Chile
| | - A Yañez
- Institute of Biochemistry and Microbiology, Faculty of Sciences, Universidad Austral de Chile, Valdivia, Chile.,FONDAP Centre: Interdisciplinary Centre for Aquaculture Research (INCAR), O'Higgins 1695, Concepción, Chile
| | - A Romero
- FONDAP Centre: Interdisciplinary Centre for Aquaculture Research (INCAR), O'Higgins 1695, Concepción, Chile.,Institute of Animal Pathology, Faculty of Veterinary Sciences, Universidad Austral de Chile. Valdivia, Chile
| | - D Haussmann
- Department of Basic Sciences, Faculty of Sciences, Universidad Santo Tomás, Valdivia, Chile
| | - J Figueroa
- Institute of Biochemistry and Microbiology, Faculty of Sciences, Universidad Austral de Chile, Valdivia, Chile.,FONDAP Centre: Interdisciplinary Centre for Aquaculture Research (INCAR), O'Higgins 1695, Concepción, Chile
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4
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Kehl A, Noster J, Hensel M. Eat in or Take out? Metabolism of Intracellular Salmonella enterica. Trends Microbiol 2020; 28:644-654. [DOI: 10.1016/j.tim.2020.03.005] [Citation(s) in RCA: 3] [Impact Index Per Article: 0.8] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/29/2019] [Revised: 03/15/2020] [Accepted: 03/25/2020] [Indexed: 02/07/2023]
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5
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Metabolic Adaptation to Sulfur of Hyperthermophilic Palaeococcus pacificus DY20341 T from Deep-Sea Hydrothermal Sediments. Int J Mol Sci 2020; 21:ijms21010368. [PMID: 31935923 PMCID: PMC6981617 DOI: 10.3390/ijms21010368] [Citation(s) in RCA: 5] [Impact Index Per Article: 1.3] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/04/2019] [Revised: 12/26/2019] [Accepted: 12/29/2019] [Indexed: 11/30/2022] Open
Abstract
The hyperthermo-piezophilic archaeon Palaeococcus pacificus DY20341T, isolated from East Pacific hydrothermal sediments, can utilize elemental sulfur as a terminal acceptor to simulate growth. To gain insight into sulfur metabolism, we performed a genomic and transcriptional analysis of Pa. pacificus DY20341T with/without elemental sulfur as an electron acceptor. In the 2001 protein-coding sequences of the genome, transcriptomic analysis showed that 108 genes increased (by up to 75.1 fold) and 336 genes decreased (by up to 13.9 fold) in the presence of elemental sulfur. Palaeococcus pacificus cultured with elemental sulfur promoted the following: the induction of membrane-bound hydrogenase (MBX), NADH:polysulfide oxidoreductase (NPSOR), NAD(P)H sulfur oxidoreductase (Nsr), sulfide dehydrogenase (SuDH), connected to the sulfur-reducing process, the upregulation of iron and nickel/cobalt transfer, iron–sulfur cluster-carrying proteins (NBP35), and some iron–sulfur cluster-containing proteins (SipA, SAM, CobQ, etc.). The accumulation of metal ions might further impact on regulators, e.g., SurR and TrmB. For growth in proteinous media without elemental sulfur, cells promoted flagelin, peptide/amino acids transporters, and maltose/sugar transporters to upregulate protein and starch/sugar utilization processes and riboflavin and thiamin biosynthesis. This indicates how strain DY20341T can adapt to different living conditions with/without elemental sulfur in the hydrothermal fields.
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6
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Pardo-Esté C, Castro-Severyn J, Krüger GI, Cabezas CE, Briones AC, Aguirre C, Morales N, Baquedano MS, Sulbaran YN, Hidalgo AA, Meneses C, Poblete-Castro I, Castro-Nallar E, Valvano MA, Saavedra CP. The Transcription Factor ArcA Modulates Salmonella's Metabolism in Response to Neutrophil Hypochlorous Acid-Mediated Stress. Front Microbiol 2019; 10:2754. [PMID: 31866961 PMCID: PMC6906141 DOI: 10.3389/fmicb.2019.02754] [Citation(s) in RCA: 7] [Impact Index Per Article: 1.4] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/12/2019] [Accepted: 11/12/2019] [Indexed: 01/03/2023] Open
Abstract
Salmonella Typhimurium, a bacterial pathogen with high metabolic plasticity, can adapt to different environmental conditions; these traits enhance its virulence by enabling bacterial survival. Neutrophils play important roles in the innate immune response, including the production of microbicidal reactive oxygen species (ROS). In addition, the myeloperoxidase in neutrophils catalyzes the formation of hypochlorous acid (HOCl), a highly toxic molecule that reacts with essential biomolecules, causing oxidative damage including lipid peroxidation and protein carbonylation. The bacterial response regulator ArcA regulates adaptive responses to oxygen levels and influences the survival of Salmonella inside phagocytic cells. Here, we demonstrate by whole transcriptomic analyses that ArcA regulates genes related to various metabolic pathways, enabling bacterial survival during HOCl-stress in vitro. Also, inside neutrophils, ArcA controls the transcription of several metabolic pathways by downregulating the expression of genes related to fatty acid degradation, lysine degradation, and arginine, proline, pyruvate, and propanoate metabolism. ArcA also upregulates genes encoding components of the oxidative pathway. These results underscore the importance of ArcA in ATP generation inside the neutrophil phagosome and its participation in bacterial metabolic adaptations during HOCl stress.
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Affiliation(s)
- Coral Pardo-Esté
- Laboratorio de Microbiología Molecular, Departamento de Ciencias Biológicas, Facultad de Ciencias de la Vida, Universidad Andres Bello, Santiago, Chile
| | - Juan Castro-Severyn
- Laboratorio de Microbiología Molecular, Departamento de Ciencias Biológicas, Facultad de Ciencias de la Vida, Universidad Andres Bello, Santiago, Chile.,Centro de Bioinformática y Biología Integrativa, Facultad de Ciencias de la Vida, Universidad Andres Bello, Santiago, Chile
| | - Gabriel I Krüger
- Laboratorio de Microbiología Molecular, Departamento de Ciencias Biológicas, Facultad de Ciencias de la Vida, Universidad Andres Bello, Santiago, Chile
| | - Carolina Elizabeth Cabezas
- Laboratorio de Microbiología Molecular, Departamento de Ciencias Biológicas, Facultad de Ciencias de la Vida, Universidad Andres Bello, Santiago, Chile
| | - Alan Cristóbal Briones
- Laboratorio de Microbiología Molecular, Departamento de Ciencias Biológicas, Facultad de Ciencias de la Vida, Universidad Andres Bello, Santiago, Chile
| | - Camila Aguirre
- Laboratorio de Microbiología Molecular, Departamento de Ciencias Biológicas, Facultad de Ciencias de la Vida, Universidad Andres Bello, Santiago, Chile
| | - Naiyulin Morales
- Laboratorio de Microbiología Molecular, Departamento de Ciencias Biológicas, Facultad de Ciencias de la Vida, Universidad Andres Bello, Santiago, Chile
| | - Maria Soledad Baquedano
- Laboratorio de Microbiología Molecular, Departamento de Ciencias Biológicas, Facultad de Ciencias de la Vida, Universidad Andres Bello, Santiago, Chile
| | - Yoelvis Noe Sulbaran
- Laboratorio de Microbiología Molecular, Departamento de Ciencias Biológicas, Facultad de Ciencias de la Vida, Universidad Andres Bello, Santiago, Chile
| | - Alejandro A Hidalgo
- Laboratorio de Patogenesis Bacteriana, Facultad de Medicina, Universidad Andres Bello, Santiago, Chile
| | - Claudio Meneses
- Centro de Biotecnología Vegetal, Facultad de Ciencias de la Vida, Universidad Andres Bello, Santiago, Chile.,FONDAP Center for Genome Regulation, Universidad Andres Bello, Santiago, Chile
| | - Ignacio Poblete-Castro
- Centro de Bioinformática y Biología Integrativa, Facultad de Ciencias de la Vida, Universidad Andres Bello, Santiago, Chile
| | - Eduardo Castro-Nallar
- Centro de Bioinformática y Biología Integrativa, Facultad de Ciencias de la Vida, Universidad Andres Bello, Santiago, Chile
| | - Miguel A Valvano
- Wellcome-Wolfson Institute for Experimental Medicine, Queen's University Belfast, Belfast, United Kingdom
| | - Claudia P Saavedra
- Laboratorio de Microbiología Molecular, Departamento de Ciencias Biológicas, Facultad de Ciencias de la Vida, Universidad Andres Bello, Santiago, Chile.,Millennium Institute on Immunology and Immunotherapy, Departamento de Ciencias Biológicas, Facultad de Ciencias de la Vida, Universidad Andres Bello, Santiago, Chile
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7
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Harrison A, Hardison RL, Wallace RM, Fitch J, Heimlich DR, Bryan MO, Dubois L, John-Williams LS, Sebra RP, White P, Moseley MA, Thompson JW, Justice SS, Mason KM. Reprioritization of biofilm metabolism is associated with nutrient adaptation and long-term survival of Haemophilus influenzae. NPJ Biofilms Microbiomes 2019; 5:33. [PMID: 31700653 PMCID: PMC6831627 DOI: 10.1038/s41522-019-0105-6] [Citation(s) in RCA: 22] [Impact Index Per Article: 4.4] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/31/2019] [Accepted: 10/03/2019] [Indexed: 01/14/2023] Open
Abstract
Nontypeable Haemophilus influenzae (NTHI) is a human-restricted pathogen with an essential requirement for heme-iron acquisition. We previously demonstrated that microevolution of NTHI promotes stationary phase survival in response to transient heme-iron restriction. In this study, we examine the metabolic contributions to biofilm formation using this evolved NTHI strain, RM33. Quantitative analyses identified 29 proteins, 55 transcripts, and 31 metabolites that significantly changed within in vitro biofilms formed by RM33. The synthesis of all enzymes within the tryptophan and glycogen pathways was significantly increased in biofilms formed by RM33 compared with the parental strain. In addition, increases were observed in metabolite transport, adhesin production, and DNA metabolism. Furthermore, we observed pyruvate as a pivotal point in the metabolic pathways associated with changes in cAMP phosphodiesterase activity during biofilm formation. Taken together, changes in central metabolism combined with increased stores of nutrients may serve to counterbalance nutrient sequestration.
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Affiliation(s)
- Alistair Harrison
- The Abigail Wexner Research Institute at Nationwide Children’s Hospital, Center for Microbial Pathogenesis, 700 Children’s Drive, Columbus, OH 43205 USA
| | - Rachael L. Hardison
- The Abigail Wexner Research Institute at Nationwide Children’s Hospital, Center for Microbial Pathogenesis, 700 Children’s Drive, Columbus, OH 43205 USA
| | - Rachel M. Wallace
- The Abigail Wexner Research Institute at Nationwide Children’s Hospital, Center for Microbial Pathogenesis, 700 Children’s Drive, Columbus, OH 43205 USA
| | - James Fitch
- The Abigail Wexner Research Institute at Nationwide Children’s Hospital, The Steve and Cindy Rasmussen Institute for Genomic Medicine, 575 Children’s Crossroad, Columbus, OH 43215 USA
| | - Derek R. Heimlich
- The Abigail Wexner Research Institute at Nationwide Children’s Hospital, Center for Microbial Pathogenesis, 700 Children’s Drive, Columbus, OH 43205 USA
| | - Meghan O’ Bryan
- The Abigail Wexner Research Institute at Nationwide Children’s Hospital, Center for Microbial Pathogenesis, 700 Children’s Drive, Columbus, OH 43205 USA
| | - Laura Dubois
- Duke Proteomics and Metabolomics Core Facility, Duke Center for Genomic and Computational Biology, Duke University, 701 West Main Street, Durham, NC 27701 USA
| | - Lisa St. John-Williams
- Duke Proteomics and Metabolomics Core Facility, Duke Center for Genomic and Computational Biology, Duke University, 701 West Main Street, Durham, NC 27701 USA
| | - Robert P. Sebra
- Icahn School of Medicine at Mount Sinai, Icahn Institute and Department of Genetics & Genomic Sciences, 1 Gustave L. Levy Place, New York, NY 10029 USA
| | - Peter White
- The Abigail Wexner Research Institute at Nationwide Children’s Hospital, The Steve and Cindy Rasmussen Institute for Genomic Medicine, 575 Children’s Crossroad, Columbus, OH 43215 USA
| | - M. Arthur Moseley
- Duke Proteomics and Metabolomics Core Facility, Duke Center for Genomic and Computational Biology, Duke University, 701 West Main Street, Durham, NC 27701 USA
| | - J. Will Thompson
- Duke Proteomics and Metabolomics Core Facility, Duke Center for Genomic and Computational Biology, Duke University, 701 West Main Street, Durham, NC 27701 USA
| | - Sheryl S. Justice
- The Abigail Wexner Research Institute at Nationwide Children’s Hospital, Center for Microbial Pathogenesis, 700 Children’s Drive, Columbus, OH 43205 USA
- Infectious Diseases Institute, The Ohio State University College of Medicine, 700 Children’s Drive, Columbus, OH 43205 USA
| | - Kevin M. Mason
- The Abigail Wexner Research Institute at Nationwide Children’s Hospital, Center for Microbial Pathogenesis, 700 Children’s Drive, Columbus, OH 43205 USA
- Infectious Diseases Institute, The Ohio State University College of Medicine, 700 Children’s Drive, Columbus, OH 43205 USA
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8
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Xu J, Preciado-Llanes L, Aulicino A, Decker CM, Depke M, Gesell Salazar M, Schmidt F, Simmons A, Huang WE. Single-Cell and Time-Resolved Profiling of Intracellular Salmonella Metabolism in Primary Human Cells. Anal Chem 2019; 91:7729-7737. [PMID: 31117406 PMCID: PMC7006958 DOI: 10.1021/acs.analchem.9b01010] [Citation(s) in RCA: 12] [Impact Index Per Article: 2.4] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/22/2022]
Abstract
![]()
The
intracellular pathogen Salmonella enterica has evolved
an array of traits for propagation and invasion of the
intestinal layers. It remains largely elusive how Salmonella adjusts its metabolic states to survive inside immune host cells.
In this study, single-cell Raman biotechnology combined with deuterium
isotope probing (Raman-DIP) have been applied to reveal metabolic
changes of the typhoidal Salmonella Typhi Ty2, the
nontyphoidal Salmonella Typhimurium LT2, and a clinical
isolate Typhimurium D23580. By initially labeling the Salmonella strains with deuterium, we employed reverse labeling to track their
metabolic changes in the time-course infection of THP-1 cell line,
human monocyte-derived dendritic cells (MoDCs) and macrophages (Mf).
We found that, in comparison with a noninvasive serovar, the invasive Salmonella strains Ty2 and D23580 have downregulated metabolic
activity inside human macrophages and dendritic cells and used lipids
as alternative carbon source, perhaps a strategy to escape from the
host immune response. Proteomic analysis using high sensitivity mass
spectrometry validated the findings of Raman-DIP analysis.
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Affiliation(s)
- Jiabao Xu
- Department of Engineering Science , University of Oxford , Parks Road , Oxford OX1 3PJ , United Kingdom
| | - Lorena Preciado-Llanes
- MRC Human Immunology Unit, Weatherall Institute of Molecular Medicine , University of Oxford , Oxford OX3 9DS , United Kingdom.,Translational Gastroenterology Unit, John Radcliffe Hospital , Headington, Oxford OX3 9DU , United Kingdom
| | - Anna Aulicino
- MRC Human Immunology Unit, Weatherall Institute of Molecular Medicine , University of Oxford , Oxford OX3 9DS , United Kingdom.,Translational Gastroenterology Unit, John Radcliffe Hospital , Headington, Oxford OX3 9DU , United Kingdom
| | - Christoph Martin Decker
- Interfaculty Institute for Genetics and Functional Genomics , University Medicine Greifswald , Felix-Hausdorff-Str. 8 , 17475 Greifswald , Germany
| | - Maren Depke
- Interfaculty Institute for Genetics and Functional Genomics , University Medicine Greifswald , Felix-Hausdorff-Str. 8 , 17475 Greifswald , Germany
| | - Manuela Gesell Salazar
- Interfaculty Institute for Genetics and Functional Genomics , University Medicine Greifswald , Felix-Hausdorff-Str. 8 , 17475 Greifswald , Germany
| | - Frank Schmidt
- Interfaculty Institute for Genetics and Functional Genomics , University Medicine Greifswald , Felix-Hausdorff-Str. 8 , 17475 Greifswald , Germany.,Proteomics Core, Weill Cornel Medicine-Qatar , Education City , PO 24144 Doha , Qatar
| | - Alison Simmons
- MRC Human Immunology Unit, Weatherall Institute of Molecular Medicine , University of Oxford , Oxford OX3 9DS , United Kingdom.,Translational Gastroenterology Unit, John Radcliffe Hospital , Headington, Oxford OX3 9DU , United Kingdom
| | - Wei E Huang
- Department of Engineering Science , University of Oxford , Parks Road , Oxford OX1 3PJ , United Kingdom
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9
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Noster J, Persicke M, Chao TC, Krone L, Heppner B, Hensel M, Hansmeier N. Impact of ROS-Induced Damage of TCA Cycle Enzymes on Metabolism and Virulence of Salmonella enterica serovar Typhimurium. Front Microbiol 2019; 10:762. [PMID: 31105651 PMCID: PMC6491894 DOI: 10.3389/fmicb.2019.00762] [Citation(s) in RCA: 25] [Impact Index Per Article: 5.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/16/2018] [Accepted: 03/26/2019] [Indexed: 01/10/2023] Open
Abstract
Salmonella enterica serovar Typhimurium (STM) is exposed to reactive oxygen species (ROS) originating from aerobic respiration, antibiotic treatment, and the oxidative burst occurring inside the Salmonella-containing vacuole (SCV) within host cells. ROS damage cellular compounds, thereby impairing bacterial viability and inducing cell death. Proteins containing iron–sulfur (Fe–S) clusters are particularly sensitive and become non-functional upon oxidation. Comprising five enzymes with Fe–S clusters, the TCA cycle is a pathway most sensitive toward ROS. To test the impact of ROS-mediated metabolic perturbations on bacterial physiology, we analyzed the proteomic and metabolic profile of STM deficient in both cytosolic superoxide dismutases (ΔsodAB). Incapable of detoxifying superoxide anions (SOA), endogenously generated SOA accumulate during growth. ΔsodAB showed reduced abundance of aconitases, leading to a metabolic profile similar to that of an aconitase-deficient strain (ΔacnAB). Furthermore, we determined a decreased expression of acnA in STM ΔsodAB. While intracellular proliferation in RAW264.7 macrophages and survival of methyl viologen treatment were not reduced for STM ΔacnAB, proteomic profiling revealed enhanced stress response. We conclude that ROS-mediated reduced expression and damage of aconitase does not impair bacterial viability or virulence, but might increase ROS amounts in STM, which reinforces the bactericidal effects of antibiotic treatment and immune responses of the host.
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Affiliation(s)
- Janina Noster
- Abteilung Mikrobiologie, Universität Osnabrück, Osnabrück, Germany
| | - Marcus Persicke
- Microbial Genomics and Biotechnology, Center for Biotechnology, Bielefeld University, Bielefeld, Germany
| | - Tzu-Chiao Chao
- Institute of Environmental Change and Society, University of Regina, Regina, SK, Canada
| | - Lena Krone
- Abteilung Mikrobiologie, Universität Osnabrück, Osnabrück, Germany
| | - Bianca Heppner
- Abteilung Mikrobiologie, Universität Osnabrück, Osnabrück, Germany
| | - Michael Hensel
- Abteilung Mikrobiologie, Universität Osnabrück, Osnabrück, Germany
| | - Nicole Hansmeier
- Abteilung Mikrobiologie, Universität Osnabrück, Osnabrück, Germany.,Institute of Environmental Change and Society, University of Regina, Regina, SK, Canada.,Luther College, University of Regina, Regina, SK, Canada
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10
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Thompson A, Fulde M, Tedin K. The metabolic pathways utilized by Salmonella Typhimurium during infection of host cells. ENVIRONMENTAL MICROBIOLOGY REPORTS 2018; 10:140-154. [PMID: 29411544 DOI: 10.1111/1758-2229.12628] [Citation(s) in RCA: 12] [Impact Index Per Article: 2.0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Subscribe] [Scholar Register] [Received: 12/19/2017] [Revised: 01/29/2018] [Accepted: 01/31/2018] [Indexed: 06/08/2023]
Abstract
Only relatively recently has research on the metabolism of intracellular bacterial pathogens within their host cells begun to appear in the published literature. This reflects in part the experimental difficulties encountered in separating host metabolic processes from those of the resident pathogen. One of the most genetically tractable and thoroughly studied intracellular bacterial pathogens, Salmonella enterica serovar Typhimurium (S. Typhimurium), has been at the forefront of metabolic studies within eukaryotic host cells. In this review, we offer a synthesis of what has been discovered to date regarding the metabolic adaptation of S. Typhimurium to survival and growth within the infected host. We discuss many studies in the context of techniques used, types of host cells, how host metabolites contribute to intracellular survival and proliferation of the pathogen and how bacterial metabolism affects the virulence and persistence of the pathogen.
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Affiliation(s)
- Arthur Thompson
- Institute for Food Research, Norwich Research Park, Norwich NR4 7UA, UK
| | - Marcus Fulde
- Centre for Infection Medicine, Institute of Microbiology and Epizootics, Freie Universität Berlin, 14163 Berlin, Germany
| | - Karsten Tedin
- Centre for Infection Medicine, Institute of Microbiology and Epizootics, Freie Universität Berlin, 14163 Berlin, Germany
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11
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Kuo CJ, Wang ST, Lin CM, Chiu HC, Huang CR, Lee DY, Chang GD, Chou TC, Chen JW, Chen CS. A multi-omic analysis reveals the role of fumarate in regulating the virulence of enterohemorrhagic Escherichia coli. Cell Death Dis 2018. [PMID: 29515100 PMCID: PMC5841434 DOI: 10.1038/s41419-018-0423-2] [Citation(s) in RCA: 17] [Impact Index Per Article: 2.8] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/16/2022]
Abstract
The enteric pathogen enterohemorrhagic Escherichia coli (EHEC) is responsible for outbreaks of bloody diarrhea and hemolytic uremic syndrome (HUS) worldwide. Several molecular mechanisms have been described for the pathogenicity of EHEC; however, the role of bacterial metabolism in the virulence of EHEC during infection in vivo remains unclear. Here we show that aerobic metabolism plays an important role in the regulation of EHEC virulence in Caenorhabditis elegans. Our functional genomic analyses showed that disruption of the genes encoding the succinate dehydrogenase complex (Sdh) of EHEC, including the sdhA gene, attenuated its toxicity toward C. elegans animals. Sdh converts succinate to fumarate and links the tricarboxylic acid (TCA) cycle and the electron transport chain (ETC) simultaneously. Succinate accumulation and fumarate depletion in the EHEC sdhA mutant cells were also demonstrated to be concomitant by metabolomic analyses. Moreover, fumarate replenishment to the sdhA mutant significantly increased its virulence toward C. elegans. These results suggest that the TCA cycle, ETC, and alteration in metabolome all account for the attenuated toxicity of the sdhA mutant, and Sdh catabolite fumarate in particular plays a critical role in the regulation of EHEC virulence. In addition, we identified the tryptophanase (TnaA) as a downstream virulence determinant of SdhA using a label-free proteomic method. We demonstrated that expression of tnaA is regulated by fumarate in EHEC. Taken together, our multi-omic analyses demonstrate that sdhA is required for the virulence of EHEC, and aerobic metabolism plays important roles in the pathogenicity of EHEC infection in C. elegans. Moreover, our study highlights the potential targeting of SdhA, if druggable, as alternative preventive or therapeutic strategies by which to combat EHEC infection.
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Affiliation(s)
- Cheng-Ju Kuo
- Department of Biochemistry and Molecular Biology, College of Medicine, National Cheng Kung University, Tainan, Taiwan.,Institute of Basic Medical Sciences, College of Medicine, National Cheng Kung University, Tainan, Taiwan
| | - Sin-Tian Wang
- Institute of Basic Medical Sciences, College of Medicine, National Cheng Kung University, Tainan, Taiwan
| | - Chia-Mei Lin
- Department of Biochemistry and Molecular Biology, College of Medicine, National Cheng Kung University, Tainan, Taiwan
| | - Hao-Chieh Chiu
- Department of Clinical Laboratory Sciences and Medical Biotechnology, National Taiwan University, Taipei, Taiwan
| | - Cheng-Rung Huang
- Department of Biochemistry and Molecular Biology, College of Medicine, National Cheng Kung University, Tainan, Taiwan.,Institute of Basic Medical Sciences, College of Medicine, National Cheng Kung University, Tainan, Taiwan
| | - Der-Yen Lee
- The Graduate Institute of Integrated Medicine, China Medical University, Taichung, Taiwan.,Graduate Institute of Biochemical Sciences, Technology Commons, Center for Systems Biology, National Taiwan University, Taipei, Taiwan
| | - Geen-Dong Chang
- Graduate Institute of Biochemical Sciences, Technology Commons, Center for Systems Biology, National Taiwan University, Taipei, Taiwan
| | - Ting-Chen Chou
- Department of Biochemistry and Molecular Biology, College of Medicine, National Cheng Kung University, Tainan, Taiwan
| | - Jenn-Wei Chen
- Institute of Basic Medical Sciences, College of Medicine, National Cheng Kung University, Tainan, Taiwan. .,Department of Microbiology and Immunology, College of Medicine, National Cheng Kung University, Tainan, Taiwan.
| | - Chang-Shi Chen
- Department of Biochemistry and Molecular Biology, College of Medicine, National Cheng Kung University, Tainan, Taiwan. .,Institute of Basic Medical Sciences, College of Medicine, National Cheng Kung University, Tainan, Taiwan.
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12
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Nho SW, Abdelhamed H, Karsi A, Lawrence ML. Improving safety of a live attenuated Edwardsiella ictaluri vaccine against enteric septicemia of catfish and evaluation of efficacy. Vet Microbiol 2017; 210:83-90. [DOI: 10.1016/j.vetmic.2017.09.004] [Citation(s) in RCA: 13] [Impact Index Per Article: 1.9] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/17/2017] [Revised: 06/26/2017] [Accepted: 09/13/2017] [Indexed: 12/19/2022]
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13
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Bumann D, Schothorst J. Intracellular Salmonella metabolism. Cell Microbiol 2017; 19. [PMID: 28672057 DOI: 10.1111/cmi.12766] [Citation(s) in RCA: 24] [Impact Index Per Article: 3.4] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/05/2017] [Revised: 06/27/2017] [Accepted: 06/30/2017] [Indexed: 12/28/2022]
Abstract
Growth of Salmonella inside infected host cells is a key aspect of their ability to cause local enteritis or systemic disease. This growth depends on exploitation of host nutrients through a large Salmonella metabolism network with hundreds of metabolites and enzymes. Studies in cell culture infection models are unravelling more and more of the underlying molecular and cellular mechanisms but also show striking Salmonella metabolic plasticity depending on host cell line and experimental conditions. In vivo studies have revealed a qualitatively diverse, but quantitatively poor, host-Salmonella nutritional interface, which on one side makes Salmonella fitness largely resilient against metabolic perturbations, but on the other side severely limits Salmonella biomass generation and growth rates. This review discusses goals and techniques for studying Salmonella intracellular metabolism, summarises main results and implications, and proposes key issues that could be addressed in future studies.
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Affiliation(s)
- Dirk Bumann
- Focal Area Infection Biology, Biozentrum, University of Basel, Basel, Switzerland
| | - Joep Schothorst
- Focal Area Infection Biology, Biozentrum, University of Basel, Basel, Switzerland
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14
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Herrero-Fresno A, Olsen JE. Salmonella Typhimurium metabolism affects virulence in the host - A mini-review. Food Microbiol 2017; 71:98-110. [PMID: 29366476 DOI: 10.1016/j.fm.2017.04.016] [Citation(s) in RCA: 38] [Impact Index Per Article: 5.4] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/22/2016] [Revised: 04/18/2017] [Accepted: 04/23/2017] [Indexed: 12/22/2022]
Abstract
Salmonella enterica remains an important food borne pathogen in all regions of the world with S. Typhimurium as one of the most frequent serovars causing food borne disease. Since the majority of human cases are caused by food of animal origin, there has been a high interest in understanding how S. Typhimurium interacts with the animal host, mostly focusing on factors that allow it to breach host barriers and to manipulate host cells to the benefit of itself. Up to recently, such studies have ignored the metabolic factors that allow the bacteria to multiply in the host, but this is changing rapidly, and we are now beginning to understand that virulence and metabolism in the host are closely linked. The current review highlights which metabolic factors that are essential for Salmonella Typhimurium growth in the intestine, in cultured epithelial and macrophage-like cell lines, at systemic sites during invasive salmonellosis, and during long term asymptomatic colonization of the host. It also points to the limitations in our current knowledge, most notably that most studies have been carried out with few well-characterized laboratory strains, that we do not know how much the in vivo metabolism differs between serotypes, and that most results are based on challenges in the mouse model of infection. It will be very important to realize whether the current understanding of Salmonella metabolism in the host is true for all serotypes and all possible hosts.
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Affiliation(s)
- Ana Herrero-Fresno
- Department of Veterinary and Animal Sciences, University of Copenhagen, Stigbøjlen 4, 1870 Frederiksberg C., Denmark
| | - John Elmerdhahl Olsen
- Department of Veterinary and Animal Sciences, University of Copenhagen, Stigbøjlen 4, 1870 Frederiksberg C., Denmark.
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15
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Liu Y, Yu K, Zhou F, Ding T, Yang Y, Hu M, Liu X. Quantitative Proteomics Charts the Landscape of Salmonella Carbon Metabolism within Host Epithelial Cells. J Proteome Res 2016; 16:788-797. [DOI: 10.1021/acs.jproteome.6b00793] [Citation(s) in RCA: 19] [Impact Index Per Article: 2.4] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/28/2022]
Affiliation(s)
- Yanhua Liu
- Institute of Analytical Chemistry
and Synthetic and Functional Biomolecules Center, College of Chemistry
and Molecular Engineering, Peking University, Beijing 100871, China
| | - Kaiwen Yu
- Institute of Analytical Chemistry
and Synthetic and Functional Biomolecules Center, College of Chemistry
and Molecular Engineering, Peking University, Beijing 100871, China
| | - Fan Zhou
- Institute of Analytical Chemistry
and Synthetic and Functional Biomolecules Center, College of Chemistry
and Molecular Engineering, Peking University, Beijing 100871, China
| | - Tao Ding
- Institute of Analytical Chemistry
and Synthetic and Functional Biomolecules Center, College of Chemistry
and Molecular Engineering, Peking University, Beijing 100871, China
| | - Yufei Yang
- Institute of Analytical Chemistry
and Synthetic and Functional Biomolecules Center, College of Chemistry
and Molecular Engineering, Peking University, Beijing 100871, China
| | - Mo Hu
- Institute of Analytical Chemistry
and Synthetic and Functional Biomolecules Center, College of Chemistry
and Molecular Engineering, Peking University, Beijing 100871, China
| | - Xiaoyun Liu
- Institute of Analytical Chemistry
and Synthetic and Functional Biomolecules Center, College of Chemistry
and Molecular Engineering, Peking University, Beijing 100871, China
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16
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Metabolic flux analyses of Pseudomonas aeruginosa cystic fibrosis isolates. Metab Eng 2016; 38:251-263. [PMID: 27637318 DOI: 10.1016/j.ymben.2016.09.002] [Citation(s) in RCA: 8] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/22/2016] [Revised: 06/07/2016] [Accepted: 09/11/2016] [Indexed: 01/22/2023]
Abstract
Pseudomonas aeruginosa is a metabolically versatile wide-ranging opportunistic pathogen. In humans P. aeruginosa causes infections of the skin, urinary tract, blood, and the lungs of Cystic Fibrosis patients. In addition, P. aeruginosa's broad environmental distribution, relatedness to biotechnologically useful species, and ability to form biofilms have made it the focus of considerable interest. We used 13C metabolic flux analysis (MFA) and flux balance analysis to understand energy and redox production and consumption and to explore the metabolic phenotypes of one reference strain and five strains isolated from the lungs of cystic fibrosis patients. Our results highlight the importance of the oxidative pentose phosphate and Entner-Doudoroff pathways in P. aeruginosa growth. Among clinical strains we report two divergent metabolic strategies and identify changes between genetically related strains that have emerged during a chronic infection of the same patient. MFA revealed that the magnitude of fluxes through the glyoxylate cycle correlates with growth rates.
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17
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Thompson AP, O'Neill I, Smith EJ, Catchpole J, Fagan A, Burgess KEV, Carmody RJ, Clarke DJ. Glycolysis and pyrimidine biosynthesis are required for replication of adherent-invasive Escherichia coli in macrophages. MICROBIOLOGY-SGM 2016; 162:954-965. [PMID: 27058922 DOI: 10.1099/mic.0.000289] [Citation(s) in RCA: 2] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [Abstract] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 12/18/2022]
Abstract
Adherent-invasive Escherichia coli (AIEC) have been implicated in the aetiology of Crohn's disease (CD), a chronic inflammatory bowel condition. It has been proposed that AIEC-infected macrophages produce high levels of pro-inflammatory cytokines thus contributing to the inflammation observed in CD. AIEC can replicate in macrophages and we wanted to determine if bacterial replication was linked to the high level of cytokine production associated with AIEC-infected macrophages. Therefore, we undertook a genetic analysis of the metabolic requirements for AIEC replication in the macrophage and we show that AIEC replication in this niche is dependent on bacterial glycolysis. In addition, our analyses indicate that AIEC have access to a wide range of nutrients in the macrophage, although the levels of purines and pyrimidines do appear to be limiting. Finally, we show that the macrophage response to AIEC infection is indistinguishable from the response to the non-replicating glycolysis mutant (ΔpfkAB) and a non-pathogenic strain of E. coli, MG1655. Therefore, AIEC does not appear to subvert the normal macrophage response to E. coli during infection.
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Affiliation(s)
- Aoife P Thompson
- School of Microbiology, University College Cork, Cork, Ireland.,APC Microbiome Institute, University College Cork, Cork, Ireland
| | - Ian O'Neill
- School of Microbiology, University College Cork, Cork, Ireland.,APC Microbiome Institute, University College Cork, Cork, Ireland
| | - Emma J Smith
- School of Microbiology, University College Cork, Cork, Ireland.,APC Microbiome Institute, University College Cork, Cork, Ireland
| | - John Catchpole
- School of Microbiology, University College Cork, Cork, Ireland.,APC Microbiome Institute, University College Cork, Cork, Ireland
| | - Ailis Fagan
- APC Microbiome Institute, University College Cork, Cork, Ireland
| | - Karl E V Burgess
- Glasgow Polyomics, University of Glasgow, Switchback Road, Glasgow G61 1QH, UK
| | | | - David J Clarke
- APC Microbiome Institute, University College Cork, Cork, Ireland.,School of Microbiology, University College Cork, Cork, Ireland
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18
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A Comparison of the ATP Generating Pathways Used by S. Typhimurium to Fuel Replication within Human and Murine Macrophage and Epithelial Cell Lines. PLoS One 2016; 11:e0150687. [PMID: 26930214 PMCID: PMC4773185 DOI: 10.1371/journal.pone.0150687] [Citation(s) in RCA: 14] [Impact Index Per Article: 1.8] [Reference Citation Analysis] [Abstract] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/20/2015] [Accepted: 02/18/2016] [Indexed: 12/21/2022] Open
Abstract
The metabolism of S. Typhimurium within infected host cells plays a fundamental role in virulence since it enables intracellular proliferation and dissemination and affects the innate immune response. An essential requirement for the intracellular replication of S. Typhimurium is the need to regenerate ATP. The metabolic route used to fulfil this requirement is the subject of the present study. For infection models we used human and murine epithelial and macrophage cell lines. The epithelial cell lines were mICc12, a transimmortalised murine colon enterocyte cell line that shows many of the characteristics of a primary epithelial cell line, and HeLa cells. The model macrophage cell lines were THP-1A human monocyte/macrophages and RAW 264.7 murine macrophages. Using a mutational approach combined with an exometabolomic analysis, we showed that neither fermentative metabolism nor anaerobic respiration play major roles in energy generation in any of the cell lines studied. Rather, we identified overflow metabolism to acetate and lactate as the foremost route by which S. Typhimurium fulfils its energy requirements.
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19
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Ehrt S, Rhee K, Schnappinger D. Mycobacterial genes essential for the pathogen's survival in the host. Immunol Rev 2015; 264:319-26. [PMID: 25703569 DOI: 10.1111/imr.12256] [Citation(s) in RCA: 40] [Impact Index Per Article: 4.4] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/11/2023]
Abstract
Mycobacterium tuberculosis (Mtb) has evolved within the human immune system as both host and reservoir. The study of genes required for its growth and persistence in vivo thus offers linked insights into its pathogenicity and host immunity. Studies of Mtb mutants have implicated metabolic adaptation (consisting of carbon, nitrogen, vitamin, and cofactor metabolism), intrabacterial pH homeostasis, and defense against reactive oxygen and reactive nitrogen species, as key determinants of its pathogenicity. However, the mechanisms of host immunity are complex and often combinatorial. Growing evidence has thus begun to reveal that the determinants of Mtb's pathogenicity may serve a broader and more complex array of functions than the isolated experimental settings in which they were initially found. Here, we review select examples, which exemplify this complexity, highlighting the distinct phases of Mtb's life cycle and the diverse microenvironments encountered therein.
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Affiliation(s)
- Sabine Ehrt
- Department of Microbiology and Immunology, Weill Cornell Medical College, New York, NY, USA
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20
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Dynamic Transcriptional Regulation of Fis in Salmonella During the Exponential Phase. Curr Microbiol 2015; 71:713-8. [PMID: 26359211 DOI: 10.1007/s00284-015-0907-6] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/18/2015] [Accepted: 08/15/2015] [Indexed: 10/23/2022]
Abstract
Fis is one of the most important global regulators and has attracted extensive research attention. Many studies have focused on comparing the Fis global regulatory networks for exploring Fis function during different growth stages, such as the exponential and stationary stages. Although the Fis protein in bacteria is mainly expressed in the exponential phase, the dynamic transcriptional regulation of Fis during the exponential phase remains poorly understood. To address this question, we used RNA-seq technology to identify the Fis-regulated genes in the S. enterica serovar Typhimurium during the early exponential phase, and qRT-PCR was performed to validate the transcriptional data. A total of 1495 Fis-regulated genes were successfully identified, including 987 Fis-repressed genes and 508 Fis-activated genes. Comparing the results of this study with those of our previous study, we found that the transcriptional regulation of Fis was diverse during the early- and mid-exponential phases. The results also showed that the strong positive regulation of Fis on Salmonella pathogenicity island genes in the mid-exponential phase transitioned into insignificant effect in the early exponential phase. To validate these results, we performed a cell infection assay and found that Δfis only exhibited a 1.49-fold decreased capacity compared with the LT2 wild-type strain, indicating a large difference from the 6.31-fold decrease observed in the mid-exponential phase. Our results provide strong evidence for a need to thoroughly understand the dynamic transcriptional regulation of Fis in Salmonella during the exponential phase.
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21
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Miyakoshi M, Chao Y, Vogel J. Cross talk between ABC transporter mRNAs via a target mRNA-derived sponge of the GcvB small RNA. EMBO J 2015; 34:1478-92. [PMID: 25630703 PMCID: PMC4474525 DOI: 10.15252/embj.201490546] [Citation(s) in RCA: 132] [Impact Index Per Article: 14.7] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/13/2014] [Revised: 12/12/2014] [Accepted: 12/15/2014] [Indexed: 11/16/2022] Open
Abstract
There is an expanding list of examples by which one mRNA can posttranscriptionally influence the expression of others. This can involve RNA sponges that sequester regulatory RNAs of mRNAs in the same regulon, but the underlying molecular mechanism of such mRNA cross talk remains little understood. Here, we report sponge-mediated mRNA cross talk in the posttranscriptional network of GcvB, a conserved Hfq-dependent small RNA with one of the largest regulons known in bacteria. We show that mRNA decay from the gltIJKL locus encoding an amino acid ABC transporter generates a stable fragment (SroC) that base-pairs with GcvB. This interaction triggers the degradation of GcvB by RNase E, alleviating the GcvB-mediated mRNA repression of other amino acid-related transport and metabolic genes. Intriguingly, since the gltIJKL mRNA itself is a target of GcvB, the SroC sponge seems to enable both an internal feed-forward loop to activate its parental mRNA in cis and activation of many trans-encoded mRNAs in the same pathway. Disabling this mRNA cross talk affects bacterial growth when peptides are the sole carbon and nitrogen sources.
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Affiliation(s)
- Masatoshi Miyakoshi
- RNA Biology Group, Institute for Molecular Infection Biology University of Würzburg, Würzburg, Germany
| | - Yanjie Chao
- RNA Biology Group, Institute for Molecular Infection Biology University of Würzburg, Würzburg, Germany
| | - Jörg Vogel
- RNA Biology Group, Institute for Molecular Infection Biology University of Würzburg, Würzburg, Germany
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22
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Dandekar T, Fieselmann A, Fischer E, Popp J, Hensel M, Noster J. Salmonella-how a metabolic generalist adopts an intracellular lifestyle during infection. Front Cell Infect Microbiol 2015; 4:191. [PMID: 25688337 PMCID: PMC4310325 DOI: 10.3389/fcimb.2014.00191] [Citation(s) in RCA: 20] [Impact Index Per Article: 2.2] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/18/2014] [Accepted: 12/21/2014] [Indexed: 12/12/2022] Open
Abstract
The human-pathogenic bacterium Salmonella enterica adjusts and adapts to different environments while attempting colonization. In the course of infection nutrient availabilities change drastically. New techniques, "-omics" data and subsequent integration by systems biology improve our understanding of these changes. We review changes in metabolism focusing on amino acid and carbohydrate metabolism. Furthermore, the adaptation process is associated with the activation of genes of the Salmonella pathogenicity islands (SPIs). Anti-infective strategies have to take these insights into account and include metabolic and other strategies. Salmonella infections will remain a challenge for infection biology.
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Affiliation(s)
- Thomas Dandekar
- Department of Bioinformatics, Biocenter, University of Würzburg Würzburg, Germany
| | - Astrid Fieselmann
- Department of Bioinformatics, Biocenter, University of Würzburg Würzburg, Germany
| | - Eva Fischer
- Department of Bioinformatics, Biocenter, University of Würzburg Würzburg, Germany
| | - Jasmin Popp
- Division of Microbiology, Biology/Chemistry, University of Osnabrück Osnabrück, Germany
| | - Michael Hensel
- Division of Microbiology, Biology/Chemistry, University of Osnabrück Osnabrück, Germany
| | - Janina Noster
- Division of Microbiology, Biology/Chemistry, University of Osnabrück Osnabrück, Germany
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23
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Bücker R, Heroven AK, Becker J, Dersch P, Wittmann C. The pyruvate-tricarboxylic acid cycle node: a focal point of virulence control in the enteric pathogen Yersinia pseudotuberculosis. J Biol Chem 2014; 289:30114-32. [PMID: 25164818 DOI: 10.1074/jbc.m114.581348] [Citation(s) in RCA: 49] [Impact Index Per Article: 4.9] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/20/2022] Open
Abstract
Despite our increasing knowledge of the specific pathogenicity factors in bacteria, the contribution of metabolic processes to virulence is largely unknown. Here, we elucidate a tight connection between pathogenicity and core metabolism in the enteric pathogen Yersinia pseudotuberculosis by integrated transcriptome and [(13)C]fluxome analysis of the wild type and virulence-regulator mutants. During aerobic growth on glucose, Y. pseudotuberculosis reveals an unusual flux distribution with a high level of secreted pyruvate. The absence of the transcriptional and post-transcriptional regulators RovA, CsrA, and Crp strongly perturbs the fluxes of carbon core metabolism at the level of pyruvate metabolism and the tricarboxylic acid (TCA) cycle, and these perturbations are accompanied by transcriptional changes in the corresponding enzymes. Knock-outs of regulators of this metabolic branch point and of its central enzyme, pyruvate kinase (ΔpykF), result in mutants with significantly reduced virulence in an oral mouse infection model. In summary, our work identifies the pyruvate-TCA cycle node as a focal point for controlling the host colonization and virulence of Yersinia.
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Affiliation(s)
- René Bücker
- From the Institute of Systems Biotechnology, Saarland University, 66123 Saarbrücken, the Institute of Biochemical Engineering, Technische Universität, Braunschweig and
| | - Ann Kathrin Heroven
- the Department of Molecular Infection Biology, Helmholtz Centre for Infection Research, 38124 Braunschweig, Germany
| | - Judith Becker
- From the Institute of Systems Biotechnology, Saarland University, 66123 Saarbrücken
| | - Petra Dersch
- the Department of Molecular Infection Biology, Helmholtz Centre for Infection Research, 38124 Braunschweig, Germany
| | - Christoph Wittmann
- From the Institute of Systems Biotechnology, Saarland University, 66123 Saarbrücken,
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24
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Condell O, Power KA, Händler K, Finn S, Sheridan A, Sergeant K, Renaut J, Burgess CM, Hinton JCD, Nally JE, Fanning S. Comparative analysis of Salmonella susceptibility and tolerance to the biocide chlorhexidine identifies a complex cellular defense network. Front Microbiol 2014; 5:373. [PMID: 25136333 PMCID: PMC4117984 DOI: 10.3389/fmicb.2014.00373] [Citation(s) in RCA: 16] [Impact Index Per Article: 1.6] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/22/2014] [Accepted: 07/03/2014] [Indexed: 12/04/2022] Open
Abstract
Chlorhexidine is one of the most widely used biocides in health and agricultural settings as well as in the modern food industry. It is a cationic biocide of the biguanide class. Details of its mechanism of action are largely unknown. The frequent use of chlorhexidine has been questioned recently, amidst concerns that an overuse of this compound may select for bacteria displaying an altered susceptibility to antimicrobials, including clinically important anti-bacterial agents. We generated a Salmonella enterica serovar Typhimurium isolate (ST24CHX) that exhibited a high-level tolerant phenotype to chlorhexidine, following several rounds of in vitro selection, using sub-lethal concentrations of the biocide. This mutant showed altered suceptibility to a panel of clinically important antimicrobial compounds. Here we describe a genomic, transcriptomic, proteomic, and phenotypic analysis of the chlorhexidine tolerant S. Typhimurium compared with its isogenic sensitive progenitor. Results from this study describe a chlorhexidine defense network that functions in both the reference chlorhexidine sensitive isolate and the tolerant mutant. The defense network involved multiple cell targets including those associated with the synthesis and modification of the cell wall, the SOS response, virulence, and a shift in cellular metabolism toward anoxic pathways, some of which were regulated by CreB and Fur. In addition, results indicated that chlorhexidine tolerance was associated with more extensive modifications of the same cellular processes involved in this proposed network, as well as a divergent defense response involving the up-regulation of additional targets such as the flagellar apparatus and an altered cellular phosphate metabolism. These data show that sub-lethal concentrations of chlorhexidine induce distinct changes in exposed Salmonella, and our findings provide insights into the mechanisms of action and tolerance to this biocidal agent.
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Affiliation(s)
- Orla Condell
- UCD Centre for Food Safety, School of Public Health, Physiotherapy and Population Science, University College Dublin Belfield, Dublin, Ireland ; European Program for Public Health Microbiology Training, European Centre for Disease Prevention and Control Stockholm, Sweden
| | - Karen A Power
- UCD Centre for Food Safety, School of Public Health, Physiotherapy and Population Science, University College Dublin Belfield, Dublin, Ireland
| | - Kristian Händler
- Department of Microbiology, School of Genetics and Microbiology, Moyne Institute of Preventive Medicine, Trinity College Dublin Dublin, Ireland
| | - Sarah Finn
- UCD Centre for Food Safety, School of Public Health, Physiotherapy and Population Science, University College Dublin Belfield, Dublin, Ireland
| | - Aine Sheridan
- Food Safety Department, Teagasc Food Research Centre Ashtown, Dublin, Ireland
| | - Kjell Sergeant
- Department of Environment and Agrobiotechnologies (EVA), Centre de Recherche Public-Gabriel Lippmann Belvaux, Luxembourg
| | - Jenny Renaut
- Department of Environment and Agrobiotechnologies (EVA), Centre de Recherche Public-Gabriel Lippmann Belvaux, Luxembourg
| | - Catherine M Burgess
- Food Safety Department, Teagasc Food Research Centre Ashtown, Dublin, Ireland
| | - Jay C D Hinton
- Department of Microbiology, School of Genetics and Microbiology, Moyne Institute of Preventive Medicine, Trinity College Dublin Dublin, Ireland ; Institute of Integrative Biology, University of Liverpool Liverpool, UK
| | - Jarlath E Nally
- School of Veterinary Medicine, University College Dublin Belfield, Dublin, Ireland
| | - Séamus Fanning
- UCD Centre for Food Safety, School of Public Health, Physiotherapy and Population Science, University College Dublin Belfield, Dublin, Ireland ; Institute for Global Food Security, Queen's University Belfast Belfast, Northern Ireland
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25
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Identification and characterization of outer membrane vesicle-associated proteins in Salmonella enterica serovar Typhimurium. Infect Immun 2014; 82:4001-10. [PMID: 24935973 DOI: 10.1128/iai.01416-13] [Citation(s) in RCA: 57] [Impact Index Per Article: 5.7] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 02/06/2023] Open
Abstract
Salmonella enterica serovar Typhimurium is a primary cause of enteric diseases and has acquired a variety of virulence factors during its evolution into a pathogen. Secreted virulence factors interact with commensal flora and host cells and enable Salmonella to survive and thrive in hostile environments. Outer membrane vesicles (OMVs) released from many Gram-negative bacteria function as a mechanism for the secretion of complex mixtures, including virulence factors. We performed a proteomic analysis of OMVs that were isolated under standard laboratory and acidic minimal medium conditions and identified 14 OMV-associated proteins that were observed in the OMV fraction isolated only under the acidic minimal medium conditions, which reproduced the nutrient-deficient intracellular milieu. The inferred roles of these 14 proteins were diverse, including transporter, enzyme, and transcriptional regulator. The absence of these proteins influenced Salmonella survival inside murine macrophages. Eleven of these proteins were predicted to possess secretion signal sequences at their N termini, and three (HupA, GlnH, and PhoN) of the proteins were found to be translocated into the cytoplasm of host cells. The comparative proteomic profiling of OMVs performed in this study revealed different protein compositions in the OMVs isolated under the two different conditions, which indicates that the OMV cargo depends on the growth conditions and provides a deeper insight into how Salmonella utilizes OMVs to adapt to environmental changes.
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26
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Tissue persistence and vaccine efficacy of tricarboxylic acid cycle and one-carbon metabolism mutant strains of Edwardsiella ictaluri. Vaccine 2014; 32:3971-6. [PMID: 24837777 DOI: 10.1016/j.vaccine.2014.05.016] [Citation(s) in RCA: 10] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/07/2014] [Revised: 04/25/2014] [Accepted: 05/01/2014] [Indexed: 11/22/2022]
Abstract
Edwardsiella ictaluri causes enteric septicemia in fish. Recently, we reported construction of E. ictaluri mutants with single and double gene deletions in tricarboxylic acid cycle (TCA) and one-carbon (C-1) metabolism. Here, we report the tissue persistence, virulence, and vaccine efficacy of TCA cycle (EiΔsdhC, EiΔfrdA, and EiΔmdh), C-1 metabolism (EiΔgcvP and EiΔglyA), and combination mutants (EiΔfrdAΔsdhC, EiΔgcvPΔsdhC, EiΔmdhΔsdhC, and EiΔgcvPΔglyA) in channel catfish. The tissue persistence study showed that EiΔsdhC, EiΔfrdA, EiΔfrdAΔsdhC, and EiΔgcvPΔsdhC were able to invade catfish and persist until 11 days post-infection. Vaccination of catfish fingerlings with all nine mutants provided significant (P<0.05) protection against subsequent challenge with the virulent parental strain. Vaccinated catfish fingerlings had 100% survival when subsequently challenged by immersion with wild-type E. ictaluri except for EiΔgcvPΔglyA and EiΔgcvP. Mutant EiΔgcvPΔsdhC was found to be very good at protecting catfish fry, as evidenced by 10-fold higher survival compared to non-vaccinated fish.
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27
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Bowden SD, Hopper-Chidlaw AC, Rice CJ, Ramachandran VK, Kelly DJ, Thompson A. Nutritional and metabolic requirements for the infection of HeLa cells by Salmonella enterica serovar Typhimurium. PLoS One 2014; 9:e96266. [PMID: 24797930 PMCID: PMC4010460 DOI: 10.1371/journal.pone.0096266] [Citation(s) in RCA: 24] [Impact Index Per Article: 2.4] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/18/2013] [Accepted: 04/07/2014] [Indexed: 12/04/2022] Open
Abstract
Salmonella is the causative agent of a spectrum of human and animal diseases ranging from gastroenteritis to typhoid fever. It is a food - and water - borne pathogen and infects via ingestion followed by invasion of intestinal epithelial cells and phagocytic cells. In this study we employed a mutational approach to define the nutrients and metabolic pathways required by Salmonella enterica serovar Typhimurium during infection of a human epithelial cell line (HeLa). We deleted the key glycolytic genes, pfkA and pfkB to show that S. Typhimurium utilizes glycolysis for replication within HeLa cells; however, glycolysis was not absolutely essential for intracellular replication. Using S. Typhimurium strains deleted for genes encoding components of the phosphotransferase system and glucose transport, we show that glucose is a major substrate required for the intracellular replication of S. Typhimurium in HeLa cells. We also deleted genes encoding enzymes involved in the utilization of gluconeogenic substrates and the glyoxylate shunt and show that neither of these pathways were required for intracellular replication of S. Typhimurium within HeLa cells.
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Affiliation(s)
- Steven D. Bowden
- Institute of Food Research, Norwich Research Park, Colney, Norwich, United Kingdom
- Graduate School of Biological Sciences, Nara Institute of Science and Technology, Ikoma, Nara, Japan
| | | | | | - Vinoy K. Ramachandran
- Institute of Food Research, Norwich Research Park, Colney, Norwich, United Kingdom
- Department of Plant Sciences, University of Oxford, Oxford, United Kingdom
| | - David J. Kelly
- Department of Molecular Biology and Biotechnology, University of Sheffield, Sheffield, United Kingdom
| | - Arthur Thompson
- Institute of Food Research, Norwich Research Park, Colney, Norwich, United Kingdom
- * E-mail:
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Hartman HB, Fell DA, Rossell S, Jensen PR, Woodward MJ, Thorndahl L, Jelsbak L, Olsen JE, Raghunathan A, Daefler S, Poolman MG. Identification of potential drug targets in Salmonella enterica sv. Typhimurium using metabolic modelling and experimental validation. MICROBIOLOGY-SGM 2014; 160:1252-1266. [PMID: 24777662 DOI: 10.1099/mic.0.076091-0] [Citation(s) in RCA: 35] [Impact Index Per Article: 3.5] [Reference Citation Analysis] [Abstract] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 11/18/2022]
Abstract
Salmonella enterica sv. Typhimurium is an established model organism for Gram-negative, intracellular pathogens. Owing to the rapid spread of resistance to antibiotics among this group of pathogens, new approaches to identify suitable target proteins are required. Based on the genome sequence of S. Typhimurium and associated databases, a genome-scale metabolic model was constructed. Output was based on an experimental determination of the biomass of Salmonella when growing in glucose minimal medium. Linear programming was used to simulate variations in the energy demand while growing in glucose minimal medium. By grouping reactions with similar flux responses, a subnetwork of 34 reactions responding to this variation was identified (the catabolic core). This network was used to identify sets of one and two reactions that when removed from the genome-scale model interfered with energy and biomass generation. Eleven such sets were found to be essential for the production of biomass precursors. Experimental investigation of seven of these showed that knockouts of the associated genes resulted in attenuated growth for four pairs of reactions, whilst three single reactions were shown to be essential for growth.
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Affiliation(s)
- Hassan B Hartman
- Department of Medical and Biological Sciences, Oxford Brookes University, Gipsy Lane, Headington, Oxford OX3 OBP, UK
| | - David A Fell
- Department of Medical and Biological Sciences, Oxford Brookes University, Gipsy Lane, Headington, Oxford OX3 OBP, UK
| | - Sergio Rossell
- Department of Systems Biology, Technical University of Denmark, Lyngby, Denmark
| | - Peter Ruhdal Jensen
- Department of Systems Biology, Technical University of Denmark, Lyngby, Denmark
| | - Martin J Woodward
- Department of Food and Nutritional Sciences, University of Reading, Reading, UK
| | - Lotte Thorndahl
- Department of Veterinary Disease Biology, University of Copenhagen, Copenhagen, Denmark
| | - Lotte Jelsbak
- Department of Veterinary Disease Biology, University of Copenhagen, Copenhagen, Denmark
| | - John Elmerdahl Olsen
- Department of Veterinary Disease Biology, University of Copenhagen, Copenhagen, Denmark
| | - Anu Raghunathan
- Department of Infectious Diseases, Mount Sinai School of Medicine, New York, NY, USA
| | - Simon Daefler
- Department of Infectious Diseases, Mount Sinai School of Medicine, New York, NY, USA
| | - Mark G Poolman
- Department of Medical and Biological Sciences, Oxford Brookes University, Gipsy Lane, Headington, Oxford OX3 OBP, UK
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Wynosky-Dolfi MA, Snyder AG, Philip NH, Doonan PJ, Poffenberger MC, Avizonis D, Zwack EE, Riblett AM, Hu B, Strowig T, Flavell RA, Jones RG, Freedman BD, Brodsky IE. Oxidative metabolism enables Salmonella evasion of the NLRP3 inflammasome. ACTA ACUST UNITED AC 2014; 211:653-68. [PMID: 24638169 PMCID: PMC3978275 DOI: 10.1084/jem.20130627] [Citation(s) in RCA: 71] [Impact Index Per Article: 7.1] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/13/2022]
Abstract
Salmonella lacking the TCA enzyme aconitase trigger NLRP3 inflammasome activation in infected macrophages, leading to elevated inflammatory responses and reduced virulence. Microbial infection triggers assembly of inflammasome complexes that promote caspase-1–dependent antimicrobial responses. Inflammasome assembly is mediated by members of the nucleotide binding domain leucine-rich repeat (NLR) protein family that respond to cytosolic bacterial products or disruption of cellular processes. Flagellin injected into host cells by invading Salmonella induces inflammasome activation through NLRC4, whereas NLRP3 is required for inflammasome activation in response to multiple stimuli, including microbial infection, tissue damage, and metabolic dysregulation, through mechanisms that remain poorly understood. During systemic infection, Salmonella avoids NLRC4 inflammasome activation by down-regulating flagellin expression. Macrophages exhibit delayed NLRP3 inflammasome activation after Salmonella infection, suggesting that Salmonella may evade or prevent the rapid activation of the NLRP3 inflammasome. We therefore screened a Salmonella Typhimurium transposon library to identify bacterial factors that limit NLRP3 inflammasome activation. Surprisingly, absence of the Salmonella TCA enzyme aconitase induced rapid NLRP3 inflammasome activation. This inflammasome activation correlated with elevated levels of bacterial citrate, and required mitochondrial reactive oxygen species and bacterial citrate synthase. Importantly, Salmonella lacking aconitase displayed NLRP3- and caspase-1/11–dependent attenuation of virulence, and induced elevated serum IL-18 in wild-type mice. Together, our data link Salmonella genes controlling oxidative metabolism to inflammasome activation and suggest that NLRP3 inflammasome evasion promotes systemic Salmonella virulence.
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Affiliation(s)
- Meghan A Wynosky-Dolfi
- Department of Pathobiology, School of Veterinary Medicine; and 2 Immunology Graduate Group and 3 Cell and Molecular Biology Graduate Group, University of Pennsylvania, Kennett Square, PA 19104
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Othman DSMP, Schirra H, McEwan AG, Kappler U. Metabolic versatility in Haemophilus influenzae: a metabolomic and genomic analysis. Front Microbiol 2014; 5:69. [PMID: 24624122 PMCID: PMC3941224 DOI: 10.3389/fmicb.2014.00069] [Citation(s) in RCA: 19] [Impact Index Per Article: 1.9] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/19/2013] [Accepted: 02/09/2014] [Indexed: 12/11/2022] Open
Abstract
Haemophilus influenzae is a host adapted human pathogen known to contribute to a variety of acute and chronic diseases of the upper and lower respiratory tract as well as the middle ear. At the sites of infection as well as during growth as a commensal the environmental conditions encountered by H. influenzae will vary significantly, especially in terms of oxygen availability, however, the mechanisms by which the bacteria can adapt their metabolism to cope with such changes have not been studied in detail. Using targeted metabolomics the spectrum of metabolites produced during growth of H. influenzae on glucose in RPMI-based medium was found to change from acetate as the main product during aerobic growth to formate as the major product during anaerobic growth. This change in end-product is likely caused by a switch in the major route of pyruvate degradation. Neither lactate nor succinate or fumarate were major products of H. influenzae growth under any condition studied. Gene expression studies and enzyme activity data revealed that despite an identical genetic makeup and very similar metabolite production profiles, H. influenzae strain Rd appeared to favor glucose degradation via the pentose phosphate pathway, while strain 2019, a clinical isolate, showed higher expression of enzymes involved in glycolysis. Components of the respiratory chain were most highly expressed during microaerophilic and anaerobic growth in both strains, but again clear differences existed in the expression of genes associated e.g., with NADH oxidation, nitrate and nitrite reduction in the two strains studied. Together our results indicate that H. influenzae uses a specialized type of metabolism that could be termed “respiration assisted fermentation” where the respiratory chain likely serves to alleviate redox imbalances caused by incomplete glucose oxidation, and at the same time provides a means of converting a variety of compounds including nitrite and nitrate that arise as part of the host defence mechanisms.
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Affiliation(s)
| | - Horst Schirra
- Centre for Advanced Imaging, The University of Queensland St. Lucia, QLD, Australia
| | - Alastair G McEwan
- School of Chemistry and Molecular Biosciences, The University of Queensland St. Lucia, QLD, Australia
| | - Ulrike Kappler
- School of Chemistry and Molecular Biosciences, The University of Queensland St. Lucia, QLD, Australia
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Troxell B, Hassan HM. Transcriptional regulation by Ferric Uptake Regulator (Fur) in pathogenic bacteria. Front Cell Infect Microbiol 2013; 3:59. [PMID: 24106689 PMCID: PMC3788343 DOI: 10.3389/fcimb.2013.00059] [Citation(s) in RCA: 290] [Impact Index Per Article: 26.4] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/24/2013] [Accepted: 09/18/2013] [Indexed: 12/16/2022] Open
Abstract
In the ancient anaerobic environment, ferrous iron (Fe2+) was one of the first metal cofactors. Oxygenation of the ancient world challenged bacteria to acquire the insoluble ferric iron (Fe3+) and later to defend against reactive oxygen species (ROS) generated by the Fenton chemistry. To acquire Fe3+, bacteria produce low-molecular weight compounds, known as siderophores, which have extremely high affinity for Fe3+. However, during infection the host restricts iron from pathogens by producing iron- and siderophore-chelating proteins, by exporting iron from intracellular pathogen-containing compartments, and by limiting absorption of dietary iron. Ferric Uptake Regulator (Fur) is a transcription factor which utilizes Fe2+ as a corepressor and represses siderophore synthesis in pathogens. Fur, directly or indirectly, controls expression of enzymes that protect against ROS damage. Thus, the challenges of iron homeostasis and defense against ROS are addressed via Fur. Although the role of Fur as a repressor is well-documented, emerging evidence demonstrates that Fur can function as an activator. Fur activation can occur through three distinct mechanisms (1) indirectly via small RNAs, (2) binding at cis regulatory elements that enhance recruitment of the RNA polymerase holoenzyme (RNAP), and (3) functioning as an antirepressor by removing or blocking DNA binding of a repressor of transcription. In addition, Fur homologs control defense against peroxide stress (PerR) and control uptake of other metals such as zinc (Zur) and manganese (Mur) in pathogenic bacteria. Fur family members are important for virulence within bacterial pathogens since mutants of fur, perR, or zur exhibit reduced virulence within numerous animal and plant models of infection. This review focuses on the breadth of Fur regulation in pathogenic bacteria.
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Affiliation(s)
- Bryan Troxell
- Department of Immunology and Microbiology, Indiana University School of Medicine Indianapolis, IN, USA
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Wang H, Liu B, Wang Q, Wang L. Genome-wide analysis of the salmonella Fis regulon and its regulatory mechanism on pathogenicity islands. PLoS One 2013; 8:e64688. [PMID: 23717649 PMCID: PMC3662779 DOI: 10.1371/journal.pone.0064688] [Citation(s) in RCA: 24] [Impact Index Per Article: 2.2] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/11/2013] [Accepted: 04/17/2013] [Indexed: 11/19/2022] Open
Abstract
Fis, one of the most important nucleoid-associated proteins, functions as a global regulator of transcription in bacteria that has been comprehensively studied in Escherichia coli K12. Fis also influences the virulence of Salmonella enterica and pathogenic E. coli by regulating their virulence genes, however, the relevant mechanism is unclear. In this report, using combined RNA-seq and chromatin immunoprecipitation (ChIP)-seq technologies, we first identified 1646 Fis-regulated genes and 885 Fis-binding targets in the S. enterica serovar Typhimurium, and found a Fis regulon different from that in E. coli. Fis has been reported to contribute to the invasion ability of S. enterica. By using cell infection assays, we found it also enhances the intracellular replication ability of S. enterica within macrophage cell, which is of central importance for the pathogenesis of infections. Salmonella pathogenicity islands (SPI)-1 and SPI-2 are crucial for the invasion and survival of S. enterica in host cells. Using mutation and overexpression experiments, real-time PCR analysis, and electrophoretic mobility shift assays, we demonstrated that Fis regulates 63 of the 94 Salmonella pathogenicity island (SPI)-1 and SPI-2 genes, by three regulatory modes: i) binds to SPI regulators in the gene body or in upstream regions; ii) binds to SPI genes directly to mediate transcriptional activation of themselves and downstream genes; iii) binds to gene encoding OmpR which affects SPI gene expression by controlling SPI regulators SsrA and HilD. Our results provide new insights into the impact of Fis on SPI genes and the pathogenicity of S. enterica.
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Affiliation(s)
- Hui Wang
- TEDA School of Biological Sciences and Biotechnology, Nankai University, TEDA, Tianjin, P. R. China
- Tianjin Key Laboratory of Microbial Functional Genomics, Tianjin, P. R. China
| | - Bin Liu
- TEDA School of Biological Sciences and Biotechnology, Nankai University, TEDA, Tianjin, P. R. China
- Tianjin Key Laboratory of Microbial Functional Genomics, Tianjin, P. R. China
| | - Quan Wang
- TEDA School of Biological Sciences and Biotechnology, Nankai University, TEDA, Tianjin, P. R. China
- Tianjin Key Laboratory of Microbial Functional Genomics, Tianjin, P. R. China
| | - Lei Wang
- TEDA School of Biological Sciences and Biotechnology, Nankai University, TEDA, Tianjin, P. R. China
- Tianjin Key Laboratory of Microbial Functional Genomics, Tianjin, P. R. China
- The Key Laboratory of Molecular Microbiology and Technology, Ministry of Education, Tianjin, P. R. China
- * E-mail:
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McNeil MB, Iglesias-Cans MC, Clulow JS, Fineran PC. YgfX (CptA) is a multimeric membrane protein that interacts with the succinate dehydrogenase assembly factor SdhE (YgfY). MICROBIOLOGY-SGM 2013; 159:1352-1365. [PMID: 23657679 DOI: 10.1099/mic.0.068510-0] [Citation(s) in RCA: 8] [Impact Index Per Article: 0.7] [Reference Citation Analysis] [Abstract] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 11/18/2022]
Abstract
Serratia sp. strain ATCC 39006 produces the red-pigmented antibiotic prodigiosin. Prodigiosin biosynthesis is regulated by a complex hierarchy that includes the uncharacterized protein YgfX (DUF1434). The ygfX gene is co-transcribed with sdhE, an FAD assembly factor essential for the flavinylation and activation of the SdhA subunit of succinate dehydrogenase (SDH), a central enzyme in the tricarboxylic acid cycle and electron transport chain. The sdhEygfX operon is highly conserved within the Enterobacteriaceae, suggesting that SdhE and YgfX function together. We performed an extensive mutagenesis to gain molecular insights into the uncharacterized protein YgfX, and have investigated the relationship between YgfX and SdhE. YgfX localized to the membrane, interacted with itself, forming dimers or larger multimers, and interacted with SdhE. The transmembrane helices of YgfX were critical for protein function and the formation of YgfX multimers. Site-directed mutagenesis of residues conserved in DUF1434 proteins revealed a periplasmic tryptophan and a cytoplasmic aspartate that were crucial for YgfX activity. Both of these amino acids were required for the formation of YgfX multimers and interactions with SdhE but not membrane localization. Multiple cell division proteins were identified as putative interaction partners of YgfX and overexpression of YgfX had effects on cell morphology. These findings represent an important step in understanding the function of DUF1434 proteins. In contrast to a recent report, we found no evidence that YgfX and SdhE form a toxin-antitoxin system. In summary, YgfX functions as a multimeric membrane-bound protein that interacts with SdhE, an important FAD assembly factor that controls SDH activity.
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Affiliation(s)
- Matthew B McNeil
- Department of Microbiology and Immunology, University of Otago, PO Box 56, Dunedin 9054, New Zealand
| | - Marina C Iglesias-Cans
- Department of Microbiology and Immunology, University of Otago, PO Box 56, Dunedin 9054, New Zealand
| | - James S Clulow
- Department of Microbiology and Immunology, University of Otago, PO Box 56, Dunedin 9054, New Zealand
| | - Peter C Fineran
- Department of Microbiology and Immunology, University of Otago, PO Box 56, Dunedin 9054, New Zealand
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Deletions in the pyruvate pathway of Salmonella Typhimurium alter SPI1-mediated gene expression and infectivity. J Anim Sci Biotechnol 2013; 4:5. [PMID: 23442379 PMCID: PMC3608087 DOI: 10.1186/2049-1891-4-5] [Citation(s) in RCA: 25] [Impact Index Per Article: 2.3] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/12/2012] [Accepted: 02/20/2013] [Indexed: 12/22/2022] Open
Abstract
BACKGROUND Salmonella enterica serovar Typhimurium is a major foodborne pathogen worldwide. S. Typhimurium encodes type III secretion systems via Salmonella pathogenicity islands (SPI), producing the major effector proteins of virulence. Previously, we identified two genes of Salmonella pyruvate metabolism that were up-regulated during chicken cell infection: pyruvate formate lyase I (pflB) and bifunctional acetaldehyde-CoA/alcohol dehydrogenase (adhE). We were therefore interested in examining the role these genes may play in the transmission of Salmonella to humans. METHODS Mutant strains of Salmonella with single gene deletions for pflB and adhE were created. Invasion and growth in human HCT-8 intestinal epithelial cells and THP-1 macrophages was examined. Quantitative PCR was performed on 19 SPI-1 genes. RESULTS In HCT-8 cells, both mutant strains had significantly higher intracellular counts than the wild-type from 4 to 48 h post-infection. Various SPI-1 genes in the mutants were up-regulated over the wild-type as early as 1 h and lasting until 24 h post-infection. In THP-1 cells, no significant difference in internal Salmonella counts was observed; however, SPI-1 genes were largely down-regulated in the mutants during the time-course of infection. We also found five SPI-1 genes - hilA, hilC hilD, sicP and rtsA - which were up-regulated in at least one of the mutant strains in log-phase broth cultures alone. We have therefore identified a set of SPI-1 virulence genes whose regulation is effected by the central metabolism of Salmonella.
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Ramachandran V, Singh R, Yang X, Tunduguru R, Mohapatra S, Khandelwal S, Patel S, Datta S. Genetic and chemical knockdown: a complementary strategy for evaluating an anti-infective target. Adv Appl Bioinform Chem 2013; 6:1-13. [PMID: 23413046 PMCID: PMC3572760 DOI: 10.2147/aabc.s39198] [Citation(s) in RCA: 12] [Impact Index Per Article: 1.1] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/01/2013] [Indexed: 11/23/2022] Open
Abstract
The equity of a drug target is principally evaluated by its genetic vulnerability with tools ranging from antisense- and microRNA-driven knockdowns to induced expression of the target protein. In order to upgrade the process of antibacterial target identification and discern its most effective type of inhibition, an in silico toolbox that evaluates its genetic and chemical vulnerability leading either to stasis or cidal outcome was constructed and validated. By precise simulation and careful experimentation using enolpyruvyl shikimate-3-phosphate synthase and its specific inhibitor glyphosate, it was shown that genetic knockdown is distinct from chemical knockdown. It was also observed that depending on the particular mechanism of inhibition, viz competitive, uncompetitive, and noncompetitive, the antimicrobial potency of an inhibitor could be orders of magnitude different. Susceptibility of Escherichia coli to glyphosate and the lack of it in Mycobacterium tuberculosis could be predicted by the in silico platform. Finally, as predicted and simulated in the in silico platform, the translation of growth inhibition to a cidal effect was able to be demonstrated experimentally by altering the carbon source from sorbitol to glucose.
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Prokaryotic assembly factors for the attachment of flavin to complex II. BIOCHIMICA ET BIOPHYSICA ACTA-BIOENERGETICS 2012; 1827:637-47. [PMID: 22985599 DOI: 10.1016/j.bbabio.2012.09.003] [Citation(s) in RCA: 18] [Impact Index Per Article: 1.5] [Reference Citation Analysis] [Abstract] [Track Full Text] [Subscribe] [Scholar Register] [Received: 07/30/2012] [Revised: 09/05/2012] [Accepted: 09/07/2012] [Indexed: 01/01/2023]
Abstract
Complex II (also known as Succinate dehydrogenase or Succinate-ubiquinone oxidoreductase) is an important respiratory enzyme that participates in both the tricarboxylic acid cycle and electron transport chain. Complex II consists of four subunits including a catalytic flavoprotein (SdhA), an iron-sulphur subunit (SdhB) and two hydrophobic membrane anchors (SdhC and SdhD). Complex II also contains a number of redox cofactors including haem, Fe-S clusters and FAD, which mediate electron transfer from succinate oxidation to the reduction of the mobile electron carrier ubiquinone. The flavin cofactor FAD is an important redox cofactor found in many proteins that participate in oxidation/reduction reactions. FAD is predominantly bound non-covalently to flavoproteins, with only a small percentage of flavoproteins, such as complex II, binding FAD covalently. Aside from a few examples, the mechanisms of flavin attachment have been a relatively unexplored area. This review will discuss the FAD cofactor and the mechanisms used by flavoproteins to covalently bind FAD. Particular focus is placed on the attachment of FAD to complex II with an emphasis on SdhE (a DUF339/SDH5 protein previously termed YgfY), the first protein identified as an assembly factor for FAD attachment to flavoproteins in prokaryotes. The molecular details of SdhE-dependent flavinylation of complex II are discussed and comparisons are made to known cofactor chaperones. Furthermore, an evolutionary hypothesis is proposed to explain the distribution of SdhE homologues in bacterial and eukaryotic species. Mechanisms for regulating SdhE function and how this may be linked to complex II function in different bacterial species are also discussed. This article is part of a Special Issue entitled: Respiratory complex II: Role in cellular physiology and disease.
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Kumar A, Henderson A, Forster GM, Goodyear AW, Weir TL, Leach JE, Dow SW, Ryan EP. Dietary rice bran promotes resistance to Salmonella enterica serovar Typhimurium colonization in mice. BMC Microbiol 2012; 12:71. [PMID: 22583915 PMCID: PMC3390288 DOI: 10.1186/1471-2180-12-71] [Citation(s) in RCA: 49] [Impact Index Per Article: 4.1] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/15/2011] [Accepted: 05/14/2012] [Indexed: 01/03/2023] Open
Abstract
Background Dietary rice bran consists of many bioactive components with disease fighting properties; including the capacity to modulate the gut microbiota. Studies point to the important roles of the gut microbiota and the mucosal epithelium in the establishment of protection against enteric pathogens, such as Salmonella. The ability of rice bran to reduce the susceptibility of mice to a Salmonella infection has not been previously investigated. Therefore, we hypothesized that the incorporation of rice bran into the diet would inhibit the colonization of Salmonella in mice through the induction of protective mucosal responses. Results Mice were fed diets containing 0%, 10% and 20% rice bran for one week prior to being orally infected with Salmonella enterica serovar Typhimurium. We found that mice consuming the 10 and 20% rice bran diets exhibited a reduction in Salmonella fecal shedding for up to nine days post-infection as compared to control diet fed animals (p < 0.05). In addition, we observed decreased concentrations of the pro-inflammatory cytokines, TNF-alpha, IFN-gamma, and IL-12 (p < 0.05) as well as increased colonization of native Lactobacillus spp. in rice bran fed mice (p < 0.05). Furthermore, in vitro experiments revealed the ability of rice bran extracts to reduce Salmonella entry into mouse small intestinal epithelial cells. Conclusions Increasing rice bran consumption represents a novel dietary means for reducing susceptibility to enteric infection with Salmonella and potentially via induction of native Lactobacillus spp.
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Affiliation(s)
- Ajay Kumar
- Department of Clinical Sciences, Colorado State University, Fort Collins, CO 80523, USA
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Dandekar T, Astrid F, Jasmin P, Hensel M. Salmonella enterica: a surprisingly well-adapted intracellular lifestyle. Front Microbiol 2012; 3:164. [PMID: 22563326 PMCID: PMC3342586 DOI: 10.3389/fmicb.2012.00164] [Citation(s) in RCA: 41] [Impact Index Per Article: 3.4] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/15/2011] [Accepted: 04/12/2012] [Indexed: 11/15/2022] Open
Abstract
The infectious intracellular lifestyle of Salmonella enterica relies on the adaptation to nutritional conditions within the Salmonella-containing vacuole (SCV) in host cells. We summarize latest results on metabolic requirements for Salmonella during infection. This includes intracellular phenotypes of mutant strains based on metabolic modeling and experimental tests, isotopolog profiling using 13C-compounds in intracellular Salmonella, and complementation of metabolic defects for attenuated mutant strains towards a comprehensive understanding of the metabolic requirements of the intracellular lifestyle of Salmonella. Helpful for this are also genomic comparisons. We outline further recent studies and which analyses of intracellular phenotypes and improved metabolic simulations were done and comment on technical required steps as well as progress involved in the iterative refinement of metabolic flux models, analyses of mutant phenotypes, and isotopolog analyses. Salmonella lifestyle is well-adapted to the SCV and its specific metabolic requirements. Salmonella metabolism adapts rapidly to SCV conditions, the metabolic generalist Salmonella is quite successful in host infection.
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Affiliation(s)
- Thomas Dandekar
- Department of Bioinformatics, Biocenter, University of Würzburg, Würzburg, Germany
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Fuchs TM, Eisenreich W, Heesemann J, Goebel W. Metabolic adaptation of human pathogenic and related nonpathogenic bacteria to extra- and intracellular habitats. FEMS Microbiol Rev 2012; 36:435-62. [DOI: 10.1111/j.1574-6976.2011.00301.x] [Citation(s) in RCA: 73] [Impact Index Per Article: 6.1] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/15/2010] [Accepted: 07/21/2011] [Indexed: 01/02/2023] Open
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40
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Richardson AR, Payne EC, Younger N, Karlinsey JE, Thomas VC, Becker LA, Navarre WW, Castor ME, Libby SJ, Fang FC. Multiple targets of nitric oxide in the tricarboxylic acid cycle of Salmonella enterica serovar typhimurium. Cell Host Microbe 2011; 10:33-43. [PMID: 21767810 DOI: 10.1016/j.chom.2011.06.004] [Citation(s) in RCA: 84] [Impact Index Per Article: 6.5] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/23/2010] [Revised: 05/06/2011] [Accepted: 06/15/2011] [Indexed: 12/22/2022]
Abstract
Host nitric oxide (NO⋅) production is important for controlling intracellular bacterial pathogens, including Salmonella enterica serovar Typhimurium, but the underlying mechanisms are incompletely understood. S. Typhmurium 14028s is prototrophic for all amino acids but cannot synthesize methionine (M) or lysine (K) during nitrosative stress. Here, we show that NO⋅-induced MK auxotrophy results from reduced succinyl-CoA availability as a consequence of NO⋅ targeting of lipoamide-dependent lipoamide dehydrogenase (LpdA) activity. LpdA is an essential component of the pyruvate and α-ketoglutarate dehydrogenase complexes. Additional effects of NO⋅ on gene regulation prevent compensatory pathways of succinyl-CoA production. Microarray analysis indicates that over 50% of the transcriptional response of S. Typhimurium to nitrosative stress is attributable to LpdA inhibition. Bacterial methionine transport is essential for virulence in NO⋅-producing mice, demonstrating that NO⋅-induced MK auxotrophy occurs in vivo. These observations underscore the importance of metabolic targets for antimicrobial actions of NO⋅.
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Affiliation(s)
- Anthony R Richardson
- Department of Laboratory Medicine, University of Washington, Seattle, WA 98195, USA
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Álvarez-Ordóñez A, Begley M, Prieto M, Messens W, López M, Bernardo A, Hill C. Salmonella spp. survival strategies within the host gastrointestinal tract. MICROBIOLOGY-SGM 2011; 157:3268-3281. [PMID: 22016569 DOI: 10.1099/mic.0.050351-0] [Citation(s) in RCA: 79] [Impact Index Per Article: 6.1] [Reference Citation Analysis] [Abstract] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 01/14/2023]
Abstract
Human salmonellosis infections are usually acquired via the food chain as a result of the ability of Salmonella serovars to colonize and persist within the gastrointestinal tract of their hosts. In addition, after food ingestion and in order to cause foodborne disease in humans, Salmonella must be able to resist several deleterious stress conditions which are part of the host defence against infections. This review gives an overview of the main defensive mechanisms involved in the Salmonella response to the extreme acid conditions of the stomach, and the elevated concentrations of bile salts, osmolytes and commensal bacterial metabolites, and the low oxygen tension conditions of the mammalian and avian gastrointestinal tracts.
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Affiliation(s)
- Avelino Álvarez-Ordóñez
- Alimentary Pharmabiotic Centre, University College Cork, Cork, Ireland.,Department of Microbiology, University College Cork, Cork, Ireland
| | - Máire Begley
- Department of Microbiology, University College Cork, Cork, Ireland
| | - Miguel Prieto
- Department of Food Hygiene and Technology, Veterinary Faculty, University of León, León, Spain
| | - Winy Messens
- Biological Hazards (BIOHAZ) Unit, European Food Safety Authority (EFSA), Largo N. Palli 5/A, I-43121 Parma, Italy
| | - Mercedes López
- Department of Food Hygiene and Technology, Veterinary Faculty, University of León, León, Spain
| | - Ana Bernardo
- Department of Food Hygiene and Technology, Veterinary Faculty, University of León, León, Spain
| | - Colin Hill
- Alimentary Pharmabiotic Centre, University College Cork, Cork, Ireland.,Department of Microbiology, University College Cork, Cork, Ireland
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