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Felipe-López A, Hansmeier N, Hensel M. Destruction of the brush border by Salmonella enterica sv. Typhimurium subverts resorption by polarized epithelial cells. Front Microbiol 2024; 15:1329798. [PMID: 38894970 PMCID: PMC11183102 DOI: 10.3389/fmicb.2024.1329798] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Grants] [Track Full Text] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/29/2023] [Accepted: 05/06/2024] [Indexed: 06/21/2024] Open
Abstract
Salmonella enterica serovar Typhimurium is an invasive, facultative intracellular gastrointestinal pathogen that destroys the brush border of polarized epithelial cells (PEC). The brush border is critical for the functions of PEC because it resorbs nutrients from the intestinal lumen and builds a physical barrier to infecting pathogens. The manipuation of PEC during infection by Salmonella was investigated by live-cell imaging and ultrastructural analysed of the brush border. We demonstrate that the destruction of the brush border by Salmonella significantly reduces the resorption surface of PEC along with the abrogation of endocytosis at the apical side of PEC. Both these changes in the physiology of PEC were associated with the translocation of type III secretion system effector protein SopE. Additionally, the F-actin polymerization rate at the apical side of PEC was highly altered by SopE, indicating that reduced endocytosis observed in infected PEC is related to the manipulation of F-actin polymerization mediated by SopE and, to a lesser extent, by effectors SopE2 or SipA. We further observed that in the absence of SopE, Salmonella effaced microvilli and induced reticular F-actin by bacterial accumulation during prolonged infection periods. In contrast to strains translocating SopE, strains lacking SopE did not alter resorption by PEC. Finally, we observed that after engulfment of Salmonella, ezrin was lost from the apical side of PEC and found later in early endosomes containing Salmonella. Our observations suggest that the destruction of the brush border by Salmonella may contribute to the pathogenesis of diarrhea.
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Affiliation(s)
| | | | - Michael Hensel
- Abt. Mikrobiologie, Universität Osnabrück, Osnabrück, Germany
- CellNanOs—Center of Cellular Nanoanalytics Osnabrück, Universität Osnabrück, Osnabrück, Germany
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2
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Cherrak Y, Salazar MA, Yilmaz K, Kreuzer M, Hardt WD. Commensal E. coli limits Salmonella gut invasion during inflammation by producing toxin-bound siderophores in a tonB-dependent manner. PLoS Biol 2024; 22:e3002616. [PMID: 38865418 PMCID: PMC11168627 DOI: 10.1371/journal.pbio.3002616] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/13/2023] [Accepted: 04/05/2024] [Indexed: 06/14/2024] Open
Abstract
The gastrointestinal tract is densely colonized by a polymicrobial community known as the microbiota which serves as primary line of defence against pathogen invasion. The microbiota can limit gut-luminal pathogen growth at different stages of infection. This can be traced to specific commensal strains exhibiting direct or indirect protective functions. Although these mechanisms hold the potential to develop new approaches to combat enteric pathogens, they remain far from being completely described. In this study, we investigated how a mouse commensal Escherichia coli can outcompete Salmonella enterica serovar Typhimurium (S. Tm). Using a salmonellosis mouse model, we found that the commensal E. coli 8178 strain relies on a trojan horse trap strategy to limit S. Tm expansion in the inflamed gut. Combining mutants and reporter tools, we demonstrated that inflammation triggers the expression of the E. coli 8178 antimicrobial microcin H47 toxin which, when fused to salmochelin siderophores, can specifically alter S. Tm growth. This protective function was compromised upon disruption of the E. coli 8178 tonB-dependent catecholate siderophore uptake system, highlighting a previously unappreciated crosstalk between iron intake and microcin H47 activity. By identifying the genetic determinants mediating S. Tm competition, our work not only provides a better mechanistic understanding of the protective function displayed by members of the gut microbiota but also further expands the general contribution of microcins in bacterial antagonistic relationships. Ultimately, such insights can open new avenues for developing microbiota-based approaches to better control intestinal infections.
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Affiliation(s)
- Yassine Cherrak
- Institute of Microbiology, Department of Biology, ETH Zurich, Zurich, Switzerland
| | - Miguel Angel Salazar
- Institute of Microbiology, Department of Biology, ETH Zurich, Zurich, Switzerland
| | - Koray Yilmaz
- Institute of Microbiology, Department of Biology, ETH Zurich, Zurich, Switzerland
| | - Markus Kreuzer
- Institute of Microbiology, Department of Biology, ETH Zurich, Zurich, Switzerland
| | - Wolf-Dietrich Hardt
- Institute of Microbiology, Department of Biology, ETH Zurich, Zurich, Switzerland
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3
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Saposnik L, Coria LM, Bruno L, Guaimas FF, Pandolfi J, Pol M, Urga ME, Sabbione F, McClelland M, Trevani A, Pasquevich KA, Cassataro J. Ecotin protects Salmonella Typhimurium against the microbicidal activity of host proteases. BIORXIV : THE PREPRINT SERVER FOR BIOLOGY 2024:2024.05.15.594389. [PMID: 38798423 PMCID: PMC11118277 DOI: 10.1101/2024.05.15.594389] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 05/29/2024]
Abstract
Salmonella enterica serovar Typhimurium causes acute diarrhea upon oral infection in humans. The harsh and proteolytic environment found in the gastrointestinal tract is the first obstacle that these bacteria face after infection. However, the mechanisms that allow Salmonella to survive the hostile conditions of the gut are poorly understood. The ecotin gene is found in an extensive range of known phyla of bacteria and it encodes a protein that has been shown to inhibit serine proteases. Thus, in the present work we studied the role of ecotin of Salmonella Typhimurium in host-pathogen interactions. We found that Salmonella Typhimurium Δ ecotin strain exhibited lower inflammation in a murine model of Salmonella induced colitis. The Δ ecotin mutant was more susceptible to the action of pancreatin and purified pancreatic elastase. In addition, the lack of ecotin led to impaired adhesion to Caco-2 and HT-29 cell lines, related to the proteolytic activity of brush border enzymes. Besides, Δ ecotin showed higher susceptibility to lysosomal proteolytic content and intracellular replication defects in macrophages. In addition, we found Ecotin to have a crucial role in Salmonella against the microbicide action of granules released and neutrophil extracellular traps from human polymorphonuclear leukocytes. Thus, the work presented here highlights the importance of ecotin in Salmonella as countermeasures against the host proteolytic defense system. IMPORTANCE The gastrointestinal tract is a very complex and harsh environment. Salmonella is a successful food borne pathogen, but little is known about its capacity to survive against the proteolysis of the gut lumen and intracellular proteases. Here, we show that Ecotin, a serine protease inhibitor, plays an important role in protecting Salmonella against proteases present at different sites encountered during oral infection. Our results indicate that Ecotin is an important virulence factor in Salmonella , adding another tool to the wide range of features this pathogen uses during oral infection.
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4
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Zhang J, Zhang S, Zhou W, Zhang X, Li G, Li R, Lin X, Chen Z, Liu F, Shen P, Zhou X, Gao Y, Chen Z, Chao Y, Wang C. A widely conserved protein Rof inhibits transcription termination factor Rho and promotes Salmonella virulence program. Nat Commun 2024; 15:3187. [PMID: 38622116 PMCID: PMC11018607 DOI: 10.1038/s41467-024-47438-7] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/06/2023] [Accepted: 03/18/2024] [Indexed: 04/17/2024] Open
Abstract
Transcription is crucial for the expression of genetic information and its efficient and accurate termination is required for all living organisms. Rho-dependent termination could rapidly terminate unwanted premature RNAs and play important roles in bacterial adaptation to changing environments. Although Rho has been discovered for about five decades, the regulation mechanisms of Rho-dependent termination are still not fully elucidated. Here we report that Rof is a conserved antiterminator and determine the cryogenic electron microscopy structure of Rho-Rof antitermination complex. Rof binds to the open-ring Rho hexamer and inhibits the initiation of Rho-dependent termination. Rof's N-terminal α-helix undergoes conformational changes upon binding with Rho, and is key in facilitating Rof-Rho interactions. Rof binds to Rho's primary binding site (PBS) and excludes Rho from binding with PBS ligand RNA at the initiation step. Further in vivo analyses in Salmonella Typhimurium show that Rof is required for virulence gene expression and host cell invasion, unveiling a physiological function of Rof and transcription termination in bacterial pathogenesis.
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Affiliation(s)
- Jing Zhang
- CAS Key Laboratory of Molecular Virology and Immunology, Center for Microbes, Development and Health (CMDH), Shanghai Institute of Immunity and Infection, Chinese Academy of Sciences, Shanghai, China
| | - Shuo Zhang
- CAS Key Laboratory of Molecular Virology and Immunology, Center for Microbes, Development and Health (CMDH), Shanghai Institute of Immunity and Infection, Chinese Academy of Sciences, Shanghai, China
- University of Chinese Academy of Sciences, Beijing, China
| | - Wei Zhou
- Department of Pharmaceutical Sciences, Beijing Institute of Radiation Medicine, Beijing, China
| | - Xiang Zhang
- The Fifth People's Hospital, Institutes of Biomedical Sciences, School of Public Health, School of Basic Medical Sciences, Fudan University, Shanghai, China
| | - Guanjin Li
- CAS Key Laboratory of Molecular Virology and Immunology, Center for Microbes, Development and Health (CMDH), Shanghai Institute of Immunity and Infection, Chinese Academy of Sciences, Shanghai, China
- University of Chinese Academy of Sciences, Beijing, China
| | - Ruoxuan Li
- CAS Key Laboratory of Molecular Virology and Immunology, Center for Microbes, Development and Health (CMDH), Shanghai Institute of Immunity and Infection, Chinese Academy of Sciences, Shanghai, China
- University of Chinese Academy of Sciences, Beijing, China
| | - Xingyu Lin
- CAS Key Laboratory of Molecular Virology and Immunology, Center for Microbes, Development and Health (CMDH), Shanghai Institute of Immunity and Infection, Chinese Academy of Sciences, Shanghai, China
- University of Chinese Academy of Sciences, Beijing, China
| | - Ziying Chen
- CAS Key Laboratory of Molecular Virology and Immunology, Center for Microbes, Development and Health (CMDH), Shanghai Institute of Immunity and Infection, Chinese Academy of Sciences, Shanghai, China
- The Fifth People's Hospital, Institutes of Biomedical Sciences, School of Public Health, School of Basic Medical Sciences, Fudan University, Shanghai, China
| | - Fang Liu
- CAS Key Laboratory of Molecular Virology and Immunology, Center for Microbes, Development and Health (CMDH), Shanghai Institute of Immunity and Infection, Chinese Academy of Sciences, Shanghai, China
| | - Pan Shen
- Department of Pharmaceutical Sciences, Beijing Institute of Radiation Medicine, Beijing, China
| | - Xiaogen Zhou
- College of Information Engineering, Zhejiang University of Technology, Hangzhou, China
| | - Yue Gao
- Department of Pharmaceutical Sciences, Beijing Institute of Radiation Medicine, Beijing, China.
| | - Zhenguo Chen
- The Fifth People's Hospital, Institutes of Biomedical Sciences, School of Public Health, School of Basic Medical Sciences, Fudan University, Shanghai, China.
| | - Yanjie Chao
- CAS Key Laboratory of Molecular Virology and Immunology, Center for Microbes, Development and Health (CMDH), Shanghai Institute of Immunity and Infection, Chinese Academy of Sciences, Shanghai, China.
- University of Chinese Academy of Sciences, Beijing, China.
- Key Laboratory of RNA Science and Engineering, Shanghai Institute of Biochemistry and Cell Biology, Center for Excellence in Molecular Cell Science, Chinese Academy of Sciences, Shanghai, China.
| | - Chengyuan Wang
- CAS Key Laboratory of Molecular Virology and Immunology, Center for Microbes, Development and Health (CMDH), Shanghai Institute of Immunity and Infection, Chinese Academy of Sciences, Shanghai, China.
- University of Chinese Academy of Sciences, Beijing, China.
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5
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Gül E, Huuskonen J, Abi Younes A, Maurer L, Enz U, Zimmermann J, Sellin ME, Bakkeren E, Hardt WD. Salmonella T3SS-2 virulence enhances gut-luminal colonization by enabling chemotaxis-dependent exploitation of intestinal inflammation. Cell Rep 2024; 43:113925. [PMID: 38460128 DOI: 10.1016/j.celrep.2024.113925] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/23/2023] [Revised: 01/12/2024] [Accepted: 02/20/2024] [Indexed: 03/11/2024] Open
Abstract
Salmonella Typhimurium (S.Tm) utilizes the chemotaxis receptor Tsr to exploit gut inflammation. However, the characteristics of this exploitation and the mechanism(s) employed by the pathogen to circumvent antimicrobial effects of inflammation are poorly defined. Here, using different naturally occurring S.Tm strains (SL1344 and 14028) and competitive infection experiments, we demonstrate that type-three secretion system (T3SS)-2 virulence is indispensable for the beneficial effects of Tsr-directed chemotaxis. The removal of the 14028-specific prophage Gifsy3, encoding virulence effectors, results in the loss of the Tsr-mediated fitness advantage in that strain. Surprisingly, without T3SS-2 effector secretion, chemotaxis toward the gut epithelium using Tsr becomes disadvantageous for either strain. Our findings reveal that luminal neutrophils recruited as a result of NLRC4 inflammasome activation locally counteract S.Tm cells exploiting the byproducts of the host immune response. This work highlights a mechanism by which S.Tm exploitation of gut inflammation for colonization relies on the coordinated effects of chemotaxis and T3SS activities.
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Affiliation(s)
- Ersin Gül
- Institute of Microbiology, Department of Biology, ETH Zurich, Zurich, Switzerland.
| | - Jemina Huuskonen
- Institute of Microbiology, Department of Biology, ETH Zurich, Zurich, Switzerland
| | - Andrew Abi Younes
- Institute of Microbiology, Department of Biology, ETH Zurich, Zurich, Switzerland
| | - Luca Maurer
- Institute of Microbiology, Department of Biology, ETH Zurich, Zurich, Switzerland
| | - Ursina Enz
- Institute of Microbiology, Department of Biology, ETH Zurich, Zurich, Switzerland
| | - Jakob Zimmermann
- Department of Visceral Surgery and Medicine, Inselspital, Bern University Hospital, University of Bern, Bern, Switzerland; Department for Biomedical Research, University of Bern, Bern, Switzerland
| | - Mikael E Sellin
- Department of Medical Biochemistry and Microbiology, Uppsala University, Uppsala, Sweden; Science for Life Laboratory, Uppsala, Sweden
| | - Erik Bakkeren
- Institute of Microbiology, Department of Biology, ETH Zurich, Zurich, Switzerland
| | - Wolf-Dietrich Hardt
- Institute of Microbiology, Department of Biology, ETH Zurich, Zurich, Switzerland.
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6
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Guo E, Chou SZ, Lara-Tejero M, Galan JE. Cryo-EM structure of the bacterial effector protein SipA bound to F-actin reveals a unique mechanism for filament stabilization. BIORXIV : THE PREPRINT SERVER FOR BIOLOGY 2024:2023.12.21.572903. [PMID: 38187563 PMCID: PMC10769390 DOI: 10.1101/2023.12.21.572903] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 01/09/2024]
Abstract
The bacterial pathogen Salmonella spp. modulates cellular processes by delivering effector proteins through its type III secretion systems. Among these effectors, SipA facilitates bacterial invasion and promotes intestinal inflammation. The mechanisms by which this effector carries out these functions are incompletely understood although SipA's ability to modulate actin dynamics is central to some of these activities. Here we report the cryo-EM structure of SipA bound to filamentous actin. We show that this effector stabilizes actin filaments through unique interactions of its carboxy terminal domain with four actin subunits. Furthermore, our structure-function studies revealed that SipA's actin-binding activity is independent from its ability to stimulate intestinal inflammation. Overall, these studies illuminate critical aspects of Salmonella pathogenesis, and provide unique insight into the mechanisms by which a bacterial effector modulates actin dynamics.
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7
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Bullones-Bolaños A, Martín-Muñoz P, Vallejo-Grijalba C, Bernal-Bayard J, Ramos-Morales F. Specificities and redundancies in the NEL family of bacterial E3 ubiquitin ligases of Salmonella enterica serovar Typhimurium. Front Immunol 2024; 15:1328707. [PMID: 38361917 PMCID: PMC10867120 DOI: 10.3389/fimmu.2024.1328707] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/27/2023] [Accepted: 01/17/2024] [Indexed: 02/17/2024] Open
Abstract
Salmonella enterica serovar Typhimurium expresses two type III secretion systems, T3SS1 and T3SS2, which are encoded in Salmonella pathogenicity island 1 (SPI1) and SPI2, respectively. These are essential virulent factors that secrete more than 40 effectors that are translocated into host animal cells. This study focuses on three of these effectors, SlrP, SspH1, and SspH2, which are members of the NEL family of E3 ubiquitin ligases. We compared their expression, regulation, and translocation patterns, their role in cell invasion and intracellular proliferation, their ability to interact and ubiquitinate specific host partners, and their effect on cytokine secretion. We found that transcription of the three genes encoding these effectors depends on the virulence regulator PhoP. Although the three effectors have the potential to be secreted through T3SS1 and T3SS2, the secretion of SspH1 and SspH2 is largely restricted to T3SS2 due to their expression pattern. We detected a role for these effectors in proliferation inside fibroblasts that is masked by redundancy. The generation of chimeric proteins allowed us to demonstrate that the N-terminal part of these proteins, containing the leucine-rich repeat motifs, confers specificity towards ubiquitination targets. Furthermore, the polyubiquitination patterns generated were different for each effector, with Lys48 linkages being predominant for SspH1 and SspH2. Finally, our experiments support an anti-inflammatory role for SspH1 and SspH2.
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Affiliation(s)
| | | | | | - Joaquín Bernal-Bayard
- Departamento de Genética, Facultad de Biología, Universidad de Sevilla, Sevilla, Spain
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8
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von Beek C, Fahlgren A, Geiser P, Di Martino ML, Lindahl O, Prensa GI, Mendez-Enriquez E, Eriksson J, Hallgren J, Fällman M, Pejler G, Sellin ME. A two-step activation mechanism enables mast cells to differentiate their response between extracellular and invasive enterobacterial infection. Nat Commun 2024; 15:904. [PMID: 38291037 PMCID: PMC10828507 DOI: 10.1038/s41467-024-45057-w] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/15/2023] [Accepted: 01/12/2024] [Indexed: 02/01/2024] Open
Abstract
Mast cells localize to mucosal tissues and contribute to innate immune defense against infection. How mast cells sense, differentiate between, and respond to bacterial pathogens remains a topic of ongoing debate. Using the prototype enteropathogen Salmonella Typhimurium (S.Tm) and other related enterobacteria, here we show that mast cells can regulate their cytokine secretion response to distinguish between extracellular and invasive bacterial infection. Tissue-invasive S.Tm and mast cells colocalize in the mouse gut during acute Salmonella infection. Toll-like Receptor 4 (TLR4) sensing of extracellular S.Tm, or pure lipopolysaccharide, causes a modest induction of cytokine transcripts and proteins, including IL-6, IL-13, and TNF. By contrast, type-III-secretion-system-1 (TTSS-1)-dependent S.Tm invasion of both mouse and human mast cells triggers rapid and potent inflammatory gene expression and >100-fold elevated cytokine secretion. The S.Tm TTSS-1 effectors SopB, SopE, and SopE2 here elicit a second activation signal, including Akt phosphorylation downstream of effector translocation, which combines with TLR activation to drive the full-blown mast cell response. Supernatants from S.Tm-infected mast cells boost macrophage survival and maturation from bone-marrow progenitors. Taken together, this study shows that mast cells can differentiate between extracellular and host-cell invasive enterobacteria via a two-step activation mechanism and tune their inflammatory output accordingly.
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Affiliation(s)
- Christopher von Beek
- Department of Medical Biochemistry and Microbiology, Uppsala University, Uppsala, Sweden
| | - Anna Fahlgren
- Department of Molecular Biology, Laboratory for Molecular Infection Medicine Sweden (MIMS), Umeå Centre for Microbial Research (UCMR), Umeå University, Umeå, Sweden
| | - Petra Geiser
- Department of Medical Biochemistry and Microbiology, Uppsala University, Uppsala, Sweden
| | | | - Otto Lindahl
- Department of Medical Biochemistry and Microbiology, Uppsala University, Uppsala, Sweden
| | - Grisna I Prensa
- Department of Medical Biochemistry and Microbiology, Uppsala University, Uppsala, Sweden
| | - Erika Mendez-Enriquez
- Department of Medical Biochemistry and Microbiology, Uppsala University, Uppsala, Sweden
| | - Jens Eriksson
- Department of Medical Biochemistry and Microbiology, Uppsala University, Uppsala, Sweden
| | - Jenny Hallgren
- Department of Medical Biochemistry and Microbiology, Uppsala University, Uppsala, Sweden
| | - Maria Fällman
- Department of Molecular Biology, Laboratory for Molecular Infection Medicine Sweden (MIMS), Umeå Centre for Microbial Research (UCMR), Umeå University, Umeå, Sweden
| | - Gunnar Pejler
- Department of Medical Biochemistry and Microbiology, Uppsala University, Uppsala, Sweden.
| | - Mikael E Sellin
- Department of Medical Biochemistry and Microbiology, Uppsala University, Uppsala, Sweden.
- Science for Life Laboratory, Uppsala, Sweden.
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Koczerka M, Lantier I, Morillon M, Deperne J, Clamagirand CD, Virlogeux-Payant I, Grépinet O. From intestine to beyond: Salmonella entry factors display distinct transcription pattern upon infection in murine models. Open Biol 2024; 14:230312. [PMID: 38228171 DOI: 10.1098/rsob.230312] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/29/2023] [Accepted: 12/14/2023] [Indexed: 01/18/2024] Open
Abstract
The infectious process of bacteria of the genus Salmonella requires the finely regulated use of various virulence factors. Among them, the type 3 secretion system-1 (T3SS-1) and the Rck and PagN invasins are involved in the internalization of the pathogen within eukaryotic cells, but their precise role in the host and in the pathogenic process is still poorly understood. In this study, we aimed to determine the kinetics of expression of these entry factors in a typhoid fever-like and a gastroenteritis model in mice by in vivo imaging using bioluminescent Salmonella Typhimurium reporter strains carrying chromosomal transcriptional fusions. Only pagN and T3SS-1 transcription has been clearly identified. Independently of the pathological model, the caecum was identified as the main transcription site of both pagN and the T3SS-1-encoding gene both at early and late stages of the infection. An intense transcription of pagN was also observed in deep organs in the typhoid fever-like model, while that of T3SS-1 remained quite sporadic in these organs, and mainly focused on the intestine all along the infection. This work will help to understand the respective role of these entry factors at the cellular level in the pathogenesis of Salmonella in vivo.
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Affiliation(s)
| | | | - Marie Morillon
- INRAE, Université de Tours, ISP, 37380, Nouzilly, France
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10
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Sun X, Yang Y, Meng X, Li J, Liu X, Liu H. PANoptosis: Mechanisms, biology, and role in disease. Immunol Rev 2024; 321:246-262. [PMID: 37823450 DOI: 10.1111/imr.13279] [Citation(s) in RCA: 4] [Impact Index Per Article: 4.0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/30/2023] [Revised: 09/16/2023] [Accepted: 09/19/2023] [Indexed: 10/13/2023]
Abstract
Cell death can be executed through distinct subroutines. PANoptosis is a unique inflammatory cell death modality involving the interactions between pyroptosis, apoptosis, and necroptosis, which can be mediated by multifaceted PANoptosome complexes assembled via integrating components from other cell death modalities. There is growing interest in the process and function of PANoptosis. Accumulating evidence suggests that PANoptosis occurs under diverse stimuli, for example, viral or bacterial infection, cytokine storm, and cancer. Given the impact of PANoptosis across the disease spectrum, this review briefly describes the relationships between pyroptosis, apoptosis, and necroptosis, highlights the key molecules in PANoptosome formation and PANoptosis activation, and outlines the multifaceted roles of PANoptosis in diseases together with a potential for therapeutic targeting. We also discuss important concepts and pressing issues for future PANoptosis research. Improved understanding of PANoptosis and its mechanisms is crucial for identifying novel therapeutic targets and strategies.
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Affiliation(s)
- Xu Sun
- Department of Integrated Chinese and Western Medicine, Affiliated Cancer Hospital of Zhengzhou University and Henan Cancer Hospital, Zhengzhou, China
| | - Yanpeng Yang
- Cardiac Care Unit, Zhengzhou Central Hospital Affiliated to Zhengzhou University, Zhengzhou, China
| | - Xiaona Meng
- Department of Integrated Chinese and Western Medicine, Affiliated Cancer Hospital of Zhengzhou University and Henan Cancer Hospital, Zhengzhou, China
| | - Jia Li
- Department of Integrated Chinese and Western Medicine, Affiliated Cancer Hospital of Zhengzhou University and Henan Cancer Hospital, Zhengzhou, China
| | - Xiaoli Liu
- Department of Integrated Chinese and Western Medicine, Affiliated Cancer Hospital of Zhengzhou University and Henan Cancer Hospital, Zhengzhou, China
| | - Huaimin Liu
- Department of Integrated Chinese and Western Medicine, Affiliated Cancer Hospital of Zhengzhou University and Henan Cancer Hospital, Zhengzhou, China
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11
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Berni M, Bolzoni L, Menozzi I, Dodi A, Bracchi C, Morganti M, Scaltriti E, Pongolini S, Tambassi M. Salmonella Derby adaptation to swine and simultaneous attenuation for humans go through decay of Salmonella Pathogenicity Island I. Microbiol Spectr 2023; 11:e0189923. [PMID: 37800927 PMCID: PMC10715017 DOI: 10.1128/spectrum.01899-23] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/19/2023] [Accepted: 08/09/2023] [Indexed: 10/07/2023] Open
Abstract
IMPORTANCE This study integrated population data with in vitro assessment of virulence phenotypes to unveil that a considerable part of the global population of Salmonella Derby is evolving to enhance its host adaptation to the swine host and that this evolution is simultaneously increasing its attenuation for humans. The study shows that the fixation of deleterious mutations in SPI-1 has a role in this process. This evidence indicates that SPI-1 has a key role for S. Derby virulence in humans but not for its circulation in swine. The results show that genes generally considered essential for Salmonella pathogenesis do not play the same key role for all Salmonella serovars or lineages and/or all hosts. The study helps in understanding the molecular mechanisms underlying the ecology and host adaptation of Salmonella showing that the adaptation process can vary for different types of Salmonella and hosts.
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Affiliation(s)
- Melissa Berni
- Risk Analysis and Genomic Epidemiology Unit, Istituto Zooprofilattico Sperimentale della Lombardia e dell'Emilia-Romagna (IZSLER), Parma, Italy
| | - Luca Bolzoni
- Risk Analysis and Genomic Epidemiology Unit, Istituto Zooprofilattico Sperimentale della Lombardia e dell'Emilia-Romagna (IZSLER), Parma, Italy
| | - Ilaria Menozzi
- Risk Analysis and Genomic Epidemiology Unit, Istituto Zooprofilattico Sperimentale della Lombardia e dell'Emilia-Romagna (IZSLER), Parma, Italy
| | - Alessandra Dodi
- Risk Analysis and Genomic Epidemiology Unit, Istituto Zooprofilattico Sperimentale della Lombardia e dell'Emilia-Romagna (IZSLER), Parma, Italy
| | - Chiara Bracchi
- Risk Analysis and Genomic Epidemiology Unit, Istituto Zooprofilattico Sperimentale della Lombardia e dell'Emilia-Romagna (IZSLER), Parma, Italy
| | - Marina Morganti
- Risk Analysis and Genomic Epidemiology Unit, Istituto Zooprofilattico Sperimentale della Lombardia e dell'Emilia-Romagna (IZSLER), Parma, Italy
| | - Erika Scaltriti
- Risk Analysis and Genomic Epidemiology Unit, Istituto Zooprofilattico Sperimentale della Lombardia e dell'Emilia-Romagna (IZSLER), Parma, Italy
| | - Stefano Pongolini
- Risk Analysis and Genomic Epidemiology Unit, Istituto Zooprofilattico Sperimentale della Lombardia e dell'Emilia-Romagna (IZSLER), Parma, Italy
| | - Martina Tambassi
- Risk Analysis and Genomic Epidemiology Unit, Istituto Zooprofilattico Sperimentale della Lombardia e dell'Emilia-Romagna (IZSLER), Parma, Italy
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12
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Fattinger SA, Maurer L, Geiser P, Bernard EM, Enz U, Ganguillet S, Gül E, Kroon S, Demarco B, Mack V, Furter M, Barthel M, Pelczar P, Shao F, Broz P, Sellin ME, Hardt WD. Gasdermin D is the only Gasdermin that provides protection against acute Salmonella gut infection in mice. Proc Natl Acad Sci U S A 2023; 120:e2315503120. [PMID: 37988464 PMCID: PMC10691232 DOI: 10.1073/pnas.2315503120] [Citation(s) in RCA: 1] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/06/2023] [Accepted: 10/05/2023] [Indexed: 11/23/2023] Open
Abstract
Gasdermins (GSDMs) share a common functional domain structure and are best known for their capacity to form membrane pores. These pores are hallmarks of a specific form of cell death called pyroptosis and mediate the secretion of pro-inflammatory cytokines such as interleukin 1β (IL1β) and interleukin 18 (IL18). Thereby, Gasdermins have been implicated in various immune responses against cancer and infectious diseases such as acute Salmonella Typhimurium (S.Tm) gut infection. However, to date, we lack a comprehensive functional assessment of the different Gasdermins (GSDMA-E) during S.Tm infection in vivo. Here, we used epithelium-specific ablation, bone marrow chimeras, and mouse lines lacking individual Gasdermins, combinations of Gasdermins or even all Gasdermins (GSDMA1-3C1-4DE) at once and performed littermate-controlled oral S.Tm infections in streptomycin-pretreated mice to investigate the impact of all murine Gasdermins. While GSDMA, C, and E appear dispensable, we show that GSDMD i) restricts S.Tm loads in the gut tissue and systemic organs, ii) controls gut inflammation kinetics, and iii) prevents epithelium disruption by 72 h of the infection. Full protection requires GSDMD expression by both bone-marrow-derived lamina propria cells and intestinal epithelial cells (IECs). In vivo experiments as well as 3D-, 2D-, and chimeric enteroid infections further show that infected IEC extrusion proceeds also without GSDMD, but that GSDMD controls the permeabilization and morphology of the extruding IECs, affects extrusion kinetics, and promotes overall mucosal barrier capacity. As such, this work identifies a unique multipronged role of GSDMD among the Gasdermins for mucosal tissue defense against a common enteric pathogen.
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Affiliation(s)
- Stefan A. Fattinger
- Department of Biology, Institute of Microbiology, ETH Zurich, Zurich8093, Switzerland
- Department of Medical Biochemistry and Microbiology, Science for Life Laboratory, Uppsala University, Uppsala75123, Sweden
- Division of Immunology and Molecular Medicine, Department of Molecular and Cell Biology, University of California, Berkeley, CA94720
| | - Luca Maurer
- Department of Biology, Institute of Microbiology, ETH Zurich, Zurich8093, Switzerland
| | - Petra Geiser
- Department of Medical Biochemistry and Microbiology, Science for Life Laboratory, Uppsala University, Uppsala75123, Sweden
| | - Elliott M. Bernard
- Department of Immunobiology, University of Lausanne, Epalinges1066, Switzerland
| | - Ursina Enz
- Department of Biology, Institute of Microbiology, ETH Zurich, Zurich8093, Switzerland
| | - Suwannee Ganguillet
- Department of Biology, Institute of Microbiology, ETH Zurich, Zurich8093, Switzerland
| | - Ersin Gül
- Department of Biology, Institute of Microbiology, ETH Zurich, Zurich8093, Switzerland
| | - Sanne Kroon
- Department of Biology, Institute of Microbiology, ETH Zurich, Zurich8093, Switzerland
| | - Benjamin Demarco
- Department of Immunobiology, University of Lausanne, Epalinges1066, Switzerland
| | - Vanessa Mack
- Department of Immunobiology, University of Lausanne, Epalinges1066, Switzerland
| | - Markus Furter
- Department of Biology, Institute of Microbiology, ETH Zurich, Zurich8093, Switzerland
| | - Manja Barthel
- Department of Biology, Institute of Microbiology, ETH Zurich, Zurich8093, Switzerland
| | - Pawel Pelczar
- Center for Transgenic Models, University of Basel, Basel4002, Switzerland
| | - Feng Shao
- National Institute of Biological Sciences, Beijing102206, China
| | - Petr Broz
- Department of Immunobiology, University of Lausanne, Epalinges1066, Switzerland
| | - Mikael E. Sellin
- Department of Medical Biochemistry and Microbiology, Science for Life Laboratory, Uppsala University, Uppsala75123, Sweden
| | - Wolf-Dietrich Hardt
- Department of Biology, Institute of Microbiology, ETH Zurich, Zurich8093, Switzerland
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13
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Gül E, Fattinger SA, Sellin ME, Hardt WD. Epithelial inflammasomes, gasdermins, and mucosal inflammation - Lessons from Salmonella and Shigella infected mice. Semin Immunol 2023; 70:101812. [PMID: 37562110 DOI: 10.1016/j.smim.2023.101812] [Citation(s) in RCA: 3] [Impact Index Per Article: 3.0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 03/31/2023] [Revised: 07/05/2023] [Accepted: 07/15/2023] [Indexed: 08/12/2023]
Abstract
Besides its crucial function in nutrient absorbance and as barrier against the microbiota, the gut epithelium is essential for sensing pathogenic insults and mounting of an appropriate early immune response. In mice, the activation of the canonical NAIP/NLRC4 inflammasome is critical for the defense against enterobacterial infections. Activation of the NAIP/NLRC4 inflammasome triggers the extrusion of infected intestinal epithelial cells (IEC) into the gut lumen, concomitant with inflammasome-mediated lytic cell death. The membrane permeabilization, a hallmark of pyroptosis, is caused by the pore-forming proteins called gasdermins (GSDMs). Recent work has revealed that NAIP/NLRC4-dependent extrusion of infected IECs can, however, also be executed in the absence of GSDMD. In fact, several reports highlighted that various cell death pathways (e.g., pyroptosis or apoptosis) and unique mechanisms specific to particular infection models and stages of gut infection are in action during epithelial inflammasome defense against intestinal pathogens. Here, we summarize the current knowledge regarding the underlying mechanisms and speculate on the putative functions of the epithelial inflammasome activation and cell death, with a particular emphasis on mouse infection models for two prominent enterobacterial pathogens, Salmonella Typhimurium and Shigella flexneri.
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Affiliation(s)
- Ersin Gül
- Institute of Microbiology, Department of Biology, ETH Zurich, Zurich, Switzerland
| | - Stefan A Fattinger
- Division of Immunology and Molecular Medicine, Department of Molecular and Cell Biology, University of California, Berkeley, CA, USA
| | - Mikael E Sellin
- Science for Life Laboratory, Department of Medical Biochemistry and Microbiology, Uppsala University, Uppsala, Sweden
| | - Wolf-Dietrich Hardt
- Institute of Microbiology, Department of Biology, ETH Zurich, Zurich, Switzerland.
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14
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Schorr L, Mathies M, Elinav E, Puschhof J. Intracellular bacteria in cancer-prospects and debates. NPJ Biofilms Microbiomes 2023; 9:76. [PMID: 37813921 PMCID: PMC10562400 DOI: 10.1038/s41522-023-00446-9] [Citation(s) in RCA: 1] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/13/2023] [Accepted: 09/26/2023] [Indexed: 10/11/2023] Open
Abstract
Recent evidence suggests that some human cancers may harbor low-biomass microbial ecosystems, spanning bacteria, viruses, and fungi. Bacteria, the most-studied kingdom in this context, are suggested by these studies to localize within cancer cells, immune cells and other tumor microenvironment cell types, where they are postulated to impact multiple cancer-related functions. Herein, we provide an overview of intratumoral bacteria, while focusing on intracellular bacteria, their suggested molecular activities, communication networks, host invasion and evasion strategies, and long-term colonization capacity. We highlight how the integration of sequencing-based and spatial techniques may enable the recognition of bacterial tumor niches. We discuss pitfalls, debates and challenges in decisively proving the existence and function of intratumoral microbes, while reaching a mechanistic elucidation of their impacts on tumor behavior and treatment responses. Together, a causative understanding of possible roles played by intracellular bacteria in cancer may enable their future utilization in diagnosis, patient stratification, and treatment.
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Affiliation(s)
- Lena Schorr
- Microbiome and Cancer Division, German Cancer Research Center, Heidelberg, Germany
- Faculty of Biosciences, Heidelberg University, Heidelberg, Germany
| | - Marius Mathies
- Microbiome and Cancer Division, German Cancer Research Center, Heidelberg, Germany
| | - Eran Elinav
- Microbiome and Cancer Division, German Cancer Research Center, Heidelberg, Germany.
- Systems Immunology Department, Weizmann Institute of Science, Rehovot, 7610001, Israel.
| | - Jens Puschhof
- Microbiome and Cancer Division, German Cancer Research Center, Heidelberg, Germany.
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15
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Wang Y, Xu X, Chen H, Yang F, Xu B, Wang K, Liu Q, Liang G, Zhang R, Jiao X, Zhang Y. Assessment of beneficial effects and identification of host adaptation-associated genes of Ligilactobacillus salivarius isolated from badgers. BMC Genomics 2023; 24:530. [PMID: 37679681 PMCID: PMC10483869 DOI: 10.1186/s12864-023-09623-8] [Citation(s) in RCA: 1] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/31/2023] [Accepted: 08/25/2023] [Indexed: 09/09/2023] Open
Abstract
BACKGROUND Ligilactobacillus salivarius has been frequently isolated from the gut microbiota of humans and domesticated animals and has been studied as a candidate probiotic. Badger (Meles meles) is known as a "generalist" species that consumes complex foods and exhibits tolerance and resistance to certain pathogens, which can be partly attributed to the beneficial microbes such as L. salivarius in the gut microbiota. However, our understanding of the beneficial traits and genomic features of badger-originated L. salivarius remains elusive. RESULTS In this study, nine L. salivarius strains were isolated from wild badgers' feces, one of which exhibited good probiotic properties. Complete genomes of the nine L. salivarius strains were generated, and comparative genomic analysis was performed with the publicly available complete genomes of L. salivarius obtained from humans and domesticated animals. The strains originating from badgers harbored a larger genome, a higher number of protein-coding sequences, and functionally annotated genes than those originating from humans and chickens. The pan-genome phylogenetic tree demonstrated that the strains originating from badgers formed a separate clade, and totally 412 gene families (12.6% of the total gene families in the pan-genome) were identified as genes gained by the last common ancestor of the badger group. The badger group harbored significantly more gene families responsible for the degradation of complex carbohydrate substrates and production of polysaccharides than strains from other hosts; many of these were acquired by gene gain events. CONCLUSIONS A candidate probiotic and nine L. salivarius complete genomes were obtained from the badgers' gut microbiome, and several beneficial genes were identified to be specifically present in the badger-originated strains that were gained in the evolution. Our study provides novel insights into the adaptation of L. salivarius to the intestinal habitat of wild badgers and provides valuable strain and genome resources for the development of L. salivarius as a probiotic.
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Affiliation(s)
- Yu Wang
- Jiangsu Co-Innovation Center for Prevention and Control of Important Animal Infectious Diseases and Zoonoses, Yangzhou University, Yangzhou, 225009, China
- Jiangsu Key Laboratory of Zoonosis, Yangzhou University, Yangzhou, 225009, China
- Joint International Research Laboratory of Agriculture and Agri-product Safety of the Ministry of Education, Yangzhou University, Yangzhou, 225009, China
- Key Laboratory of Prevention and Control of Biological Hazard Factors (Animal Origin) for Agrifood Safety and Quality, Ministry of Agriculture of China, Yangzhou University, Yangzhou, 225009, China
| | - Xiaomeng Xu
- Jiangsu Co-Innovation Center for Prevention and Control of Important Animal Infectious Diseases and Zoonoses, Yangzhou University, Yangzhou, 225009, China
- Jiangsu Key Laboratory of Zoonosis, Yangzhou University, Yangzhou, 225009, China
- Joint International Research Laboratory of Agriculture and Agri-product Safety of the Ministry of Education, Yangzhou University, Yangzhou, 225009, China
- Key Laboratory of Prevention and Control of Biological Hazard Factors (Animal Origin) for Agrifood Safety and Quality, Ministry of Agriculture of China, Yangzhou University, Yangzhou, 225009, China
| | - Huan Chen
- Jiangsu Co-Innovation Center for Prevention and Control of Important Animal Infectious Diseases and Zoonoses, Yangzhou University, Yangzhou, 225009, China
- Jiangsu Key Laboratory of Zoonosis, Yangzhou University, Yangzhou, 225009, China
- Joint International Research Laboratory of Agriculture and Agri-product Safety of the Ministry of Education, Yangzhou University, Yangzhou, 225009, China
- Key Laboratory of Prevention and Control of Biological Hazard Factors (Animal Origin) for Agrifood Safety and Quality, Ministry of Agriculture of China, Yangzhou University, Yangzhou, 225009, China
| | - Fang Yang
- Jiangsu Co-Innovation Center for Prevention and Control of Important Animal Infectious Diseases and Zoonoses, Yangzhou University, Yangzhou, 225009, China
- Jiangsu Key Laboratory of Zoonosis, Yangzhou University, Yangzhou, 225009, China
- Joint International Research Laboratory of Agriculture and Agri-product Safety of the Ministry of Education, Yangzhou University, Yangzhou, 225009, China
- Key Laboratory of Prevention and Control of Biological Hazard Factors (Animal Origin) for Agrifood Safety and Quality, Ministry of Agriculture of China, Yangzhou University, Yangzhou, 225009, China
| | - Bo Xu
- Jiangsu Co-Innovation Center for Prevention and Control of Important Animal Infectious Diseases and Zoonoses, Yangzhou University, Yangzhou, 225009, China
- Jiangsu Key Laboratory of Zoonosis, Yangzhou University, Yangzhou, 225009, China
- Joint International Research Laboratory of Agriculture and Agri-product Safety of the Ministry of Education, Yangzhou University, Yangzhou, 225009, China
- Key Laboratory of Prevention and Control of Biological Hazard Factors (Animal Origin) for Agrifood Safety and Quality, Ministry of Agriculture of China, Yangzhou University, Yangzhou, 225009, China
| | - Kun Wang
- Jiangsu Co-Innovation Center for Prevention and Control of Important Animal Infectious Diseases and Zoonoses, Yangzhou University, Yangzhou, 225009, China
- Jiangsu Key Laboratory of Zoonosis, Yangzhou University, Yangzhou, 225009, China
- Joint International Research Laboratory of Agriculture and Agri-product Safety of the Ministry of Education, Yangzhou University, Yangzhou, 225009, China
- Key Laboratory of Prevention and Control of Biological Hazard Factors (Animal Origin) for Agrifood Safety and Quality, Ministry of Agriculture of China, Yangzhou University, Yangzhou, 225009, China
| | - Qianwen Liu
- Jiangsu Co-Innovation Center for Prevention and Control of Important Animal Infectious Diseases and Zoonoses, Yangzhou University, Yangzhou, 225009, China
- Jiangsu Key Laboratory of Zoonosis, Yangzhou University, Yangzhou, 225009, China
- Joint International Research Laboratory of Agriculture and Agri-product Safety of the Ministry of Education, Yangzhou University, Yangzhou, 225009, China
- Key Laboratory of Prevention and Control of Biological Hazard Factors (Animal Origin) for Agrifood Safety and Quality, Ministry of Agriculture of China, Yangzhou University, Yangzhou, 225009, China
| | - Guixin Liang
- Jiangsu Co-Innovation Center for Prevention and Control of Important Animal Infectious Diseases and Zoonoses, Yangzhou University, Yangzhou, 225009, China
- Jiangsu Key Laboratory of Zoonosis, Yangzhou University, Yangzhou, 225009, China
- Joint International Research Laboratory of Agriculture and Agri-product Safety of the Ministry of Education, Yangzhou University, Yangzhou, 225009, China
- Key Laboratory of Prevention and Control of Biological Hazard Factors (Animal Origin) for Agrifood Safety and Quality, Ministry of Agriculture of China, Yangzhou University, Yangzhou, 225009, China
| | - Ruiqi Zhang
- Jiangsu Co-Innovation Center for Prevention and Control of Important Animal Infectious Diseases and Zoonoses, Yangzhou University, Yangzhou, 225009, China
- Jiangsu Key Laboratory of Zoonosis, Yangzhou University, Yangzhou, 225009, China
- Joint International Research Laboratory of Agriculture and Agri-product Safety of the Ministry of Education, Yangzhou University, Yangzhou, 225009, China
- Key Laboratory of Prevention and Control of Biological Hazard Factors (Animal Origin) for Agrifood Safety and Quality, Ministry of Agriculture of China, Yangzhou University, Yangzhou, 225009, China
| | - Xin'an Jiao
- Jiangsu Co-Innovation Center for Prevention and Control of Important Animal Infectious Diseases and Zoonoses, Yangzhou University, Yangzhou, 225009, China.
- Jiangsu Key Laboratory of Zoonosis, Yangzhou University, Yangzhou, 225009, China.
- Joint International Research Laboratory of Agriculture and Agri-product Safety of the Ministry of Education, Yangzhou University, Yangzhou, 225009, China.
- Key Laboratory of Prevention and Control of Biological Hazard Factors (Animal Origin) for Agrifood Safety and Quality, Ministry of Agriculture of China, Yangzhou University, Yangzhou, 225009, China.
| | - Yunzeng Zhang
- Jiangsu Co-Innovation Center for Prevention and Control of Important Animal Infectious Diseases and Zoonoses, Yangzhou University, Yangzhou, 225009, China.
- Jiangsu Key Laboratory of Zoonosis, Yangzhou University, Yangzhou, 225009, China.
- Joint International Research Laboratory of Agriculture and Agri-product Safety of the Ministry of Education, Yangzhou University, Yangzhou, 225009, China.
- Key Laboratory of Prevention and Control of Biological Hazard Factors (Animal Origin) for Agrifood Safety and Quality, Ministry of Agriculture of China, Yangzhou University, Yangzhou, 225009, China.
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16
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Gül E, Bakkeren E, Salazar G, Steiger Y, Abi Younes A, Clerc M, Christen P, Fattinger SA, Nguyen BD, Kiefer P, Slack E, Ackermann M, Vorholt JA, Sunagawa S, Diard M, Hardt WD. The microbiota conditions a gut milieu that selects for wild-type Salmonella Typhimurium virulence. PLoS Biol 2023; 21:e3002253. [PMID: 37651408 PMCID: PMC10499267 DOI: 10.1371/journal.pbio.3002253] [Citation(s) in RCA: 1] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/28/2023] [Revised: 09/13/2023] [Accepted: 07/13/2023] [Indexed: 09/02/2023] Open
Abstract
Salmonella Typhimurium elicits gut inflammation by the costly expression of HilD-controlled virulence factors. This inflammation alleviates colonization resistance (CR) mediated by the microbiota and thereby promotes pathogen blooms. However, the inflamed gut-milieu can also select for hilD mutants, which cannot elicit or maintain inflammation, therefore causing a loss of the pathogen's virulence. This raises the question of which conditions support the maintenance of virulence in S. Typhimurium. Indeed, it remains unclear why the wild-type hilD allele is dominant among natural isolates. Here, we show that microbiota transfer from uninfected or recovered hosts leads to rapid clearance of hilD mutants that feature attenuated virulence, and thereby contributes to the preservation of the virulent S. Typhimurium genotype. Using mouse models featuring a range of microbiota compositions and antibiotic- or inflammation-inflicted microbiota disruptions, we found that irreversible disruption of the microbiota leads to the accumulation of hilD mutants. In contrast, in models with a transient microbiota disruption, selection for hilD mutants was prevented by the regrowing microbiota community dominated by Lachnospirales and Oscillospirales. Strikingly, even after an irreversible microbiota disruption, microbiota transfer from uninfected donors prevented the rise of hilD mutants. Our results establish that robust S. Typhimurium gut colonization hinges on optimizing its manipulation of the host: A transient and tempered microbiota perturbation is favorable for the pathogen to both flourish in the inflamed gut and also minimize loss of virulence. Moreover, besides conferring CR, the microbiota may have the additional consequence of maintaining costly enteropathogen virulence mechanisms.
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Affiliation(s)
- Ersin Gül
- Institute of Microbiology, Department of Biology, ETH Zurich, Zurich, Switzerland
| | - Erik Bakkeren
- Institute of Microbiology, Department of Biology, ETH Zurich, Zurich, Switzerland
- Department of Biology, University of Oxford, Oxford, United Kingdom
- Department of Biochemistry, University of Oxford, Oxford, United Kingdom
| | - Guillem Salazar
- Institute of Microbiology, Department of Biology, ETH Zurich, Zurich, Switzerland
- Institute of Microbiology and Swiss Institute of Bioinformatics, Department of Biology, ETH Zürich, Zürich, Switzerland
| | - Yves Steiger
- Institute of Microbiology, Department of Biology, ETH Zurich, Zurich, Switzerland
| | - Andrew Abi Younes
- Institute of Microbiology, Department of Biology, ETH Zurich, Zurich, Switzerland
| | - Melanie Clerc
- Institute of Microbiology, Department of Biology, ETH Zurich, Zurich, Switzerland
| | - Philipp Christen
- Institute of Microbiology, Department of Biology, ETH Zurich, Zurich, Switzerland
| | - Stefan A. Fattinger
- Institute of Microbiology, Department of Biology, ETH Zurich, Zurich, Switzerland
- Science for Life Laboratory, Department of Medical Biochemistry and Microbiology, Uppsala University, Uppsala, Sweden
| | - Bidong D. Nguyen
- Institute of Microbiology, Department of Biology, ETH Zurich, Zurich, Switzerland
| | - Patrick Kiefer
- Institute of Microbiology, Department of Biology, ETH Zurich, Zurich, Switzerland
| | - Emma Slack
- Institute of Microbiology, Department of Biology, ETH Zurich, Zurich, Switzerland
- Institute for Food, Nutrition and Health, ETH Zürich, Zürich, Switzerland
| | - Martin Ackermann
- Institute of Biogeochemistry and Pollutant Dynamics, Department of Environmental Systems Science, ETH Zurich, Zurich, Switzerland
- Department of Environmental Microbiology, Eawag, Duebendorf, Switzerland
| | - Julia A. Vorholt
- Institute of Microbiology, Department of Biology, ETH Zurich, Zurich, Switzerland
| | - Shinichi Sunagawa
- Institute of Microbiology, Department of Biology, ETH Zurich, Zurich, Switzerland
- Institute of Microbiology and Swiss Institute of Bioinformatics, Department of Biology, ETH Zürich, Zürich, Switzerland
| | - Médéric Diard
- Biozentrum, University of Basel, Basel, Switzerland
- Botnar Research Centre for Child Health, Basel, Switzerland
| | - Wolf-Dietrich Hardt
- Institute of Microbiology, Department of Biology, ETH Zurich, Zurich, Switzerland
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17
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Caballero-Flores G, Pickard JM, Núñez G. Microbiota-mediated colonization resistance: mechanisms and regulation. Nat Rev Microbiol 2023; 21:347-360. [PMID: 36539611 PMCID: PMC10249723 DOI: 10.1038/s41579-022-00833-7] [Citation(s) in RCA: 53] [Impact Index Per Article: 53.0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Accepted: 11/16/2022] [Indexed: 12/24/2022]
Abstract
A dense and diverse microbial community inhabits the gut and many epithelial surfaces. Referred to as the microbiota, it co-evolved with the host and is beneficial for many host physiological processes. A major function of these symbiotic microorganisms is protection against pathogen colonization and overgrowth of indigenous pathobionts. Dysbiosis of the normal microbial community increases the risk of pathogen infection and overgrowth of harmful pathobionts. The protective mechanisms conferred by the microbiota are complex and include competitive microbial-microbial interactions and induction of host immune responses. Pathogens, in turn, have evolved multiple strategies to subvert colonization resistance conferred by the microbiota. Understanding the mechanisms by which microbial symbionts limit pathogen colonization should guide the development of new therapeutic approaches to prevent or treat disease.
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Affiliation(s)
- Gustavo Caballero-Flores
- Department of Pathology and Rogel Cancer Center, The University of Michigan Medical School, Ann Arbor, MI, USA.
| | - Joseph M Pickard
- Department of Pathology and Rogel Cancer Center, The University of Michigan Medical School, Ann Arbor, MI, USA
| | - Gabriel Núñez
- Department of Pathology and Rogel Cancer Center, The University of Michigan Medical School, Ann Arbor, MI, USA.
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18
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Davidson A, Hume PJ, Greene NP, Koronakis V. Salmonella invasion of a cell is self-limiting due to effector-driven activation of N-WASP. iScience 2023; 26:106643. [PMID: 37168569 PMCID: PMC10164908 DOI: 10.1016/j.isci.2023.106643] [Citation(s) in RCA: 1] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/30/2023] [Revised: 03/10/2023] [Accepted: 04/06/2023] [Indexed: 05/13/2023] Open
Abstract
Salmonella Typhimurium drives uptake into non-phagocytic host cells by injecting effector proteins that reorganize the actin cytoskeleton. The host actin regulator N-WASP has been implicated in bacterial entry, but its precise role is not clear. We demonstrate that Cdc42-dependent N-WASP activation, instigated by the Cdc42-activating effector SopE2, strongly impedes Salmonella uptake into host cells. This inhibitory pathway is predominant later in invasion, with the ubiquitin ligase activity of the effector SopA specifically interfering with negative Cdc42-N-WASP signaling at early stages. The cell therefore transitions from being susceptible to invasion, into a state almost completely recalcitrant to bacterial uptake, providing a mechanism to limit the number of internalized Salmonella. Our work raises the possibility that Cdc42-N-WASP, known to be activated by numerous bacterial and viral species during infection and commonly assumed to promote pathogen uptake, is used to limit the entry of multiple pathogens.
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Affiliation(s)
| | - Peter J. Hume
- Department of Pathology, University of Cambridge, Cambridge, UK
| | | | - Vassilis Koronakis
- Department of Pathology, University of Cambridge, Cambridge, UK
- Corresponding author
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19
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Teklemariam AD, Al-Hindi RR, Albiheyri RS, Alharbi MG, Alghamdi MA, Filimban AAR, Al Mutiri AS, Al-Alyani AM, Alseghayer MS, Almaneea AM, Albar AH, Khormi MA, Bhunia AK. Human Salmonellosis: A Continuous Global Threat in the Farm-to-Fork Food Safety Continuum. Foods 2023; 12:foods12091756. [PMID: 37174295 PMCID: PMC10178548 DOI: 10.3390/foods12091756] [Citation(s) in RCA: 5] [Impact Index Per Article: 5.0] [Reference Citation Analysis] [Abstract] [Key Words] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/24/2023] [Revised: 04/18/2023] [Accepted: 04/20/2023] [Indexed: 05/15/2023] Open
Abstract
Salmonella is one of the most common zoonotic foodborne pathogens and a worldwide public health threat. Salmonella enterica is the most pathogenic among Salmonella species, comprising over 2500 serovars. It causes typhoid fever and gastroenteritis, and the serovars responsible for the later disease are known as non-typhoidal Salmonella (NTS). Salmonella transmission to humans happens along the farm-to-fork continuum via contaminated animal- and plant-derived foods, including poultry, eggs, fish, pork, beef, vegetables, fruits, nuts, and flour. Several virulence factors have been recognized to play a vital role in attaching, invading, and evading the host defense system. These factors include capsule, adhesion proteins, flagella, plasmids, and type III secretion systems that are encoded on the Salmonella pathogenicity islands. The increased global prevalence of NTS serovars in recent years indicates that the control approaches centered on alleviating the food animals' contamination along the food chain have been unsuccessful. Moreover, the emergence of antibiotic-resistant Salmonella variants suggests a potential food safety crisis. This review summarizes the current state of the knowledge on the nomenclature, microbiological features, virulence factors, and the mechanism of antimicrobial resistance of Salmonella. Furthermore, it provides insights into the pathogenesis and epidemiology of Salmonella infections. The recent outbreaks of salmonellosis reported in different clinical settings and geographical regions, including Africa, the Middle East and North Africa, Latin America, Europe, and the USA in the farm-to-fork continuum, are also highlighted.
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Affiliation(s)
- Addisu D Teklemariam
- Department of Biological Sciences, Faculty of Science, King Abdulaziz University, Jeddah 21589, Saudi Arabia
| | - Rashad R Al-Hindi
- Department of Biological Sciences, Faculty of Science, King Abdulaziz University, Jeddah 21589, Saudi Arabia
| | - Raed S Albiheyri
- Department of Biological Sciences, Faculty of Science, King Abdulaziz University, Jeddah 21589, Saudi Arabia
- Centre of Excellence in Bionanoscience Research, King Abdulaziz University, Jeddah 21589, Saudi Arabia
| | - Mona G Alharbi
- Department of Biological Sciences, Faculty of Science, King Abdulaziz University, Jeddah 21589, Saudi Arabia
| | - Mashail A Alghamdi
- Department of Biological Sciences, Faculty of Science, King Abdulaziz University, Jeddah 21589, Saudi Arabia
| | - Amani A R Filimban
- Department of Biological Sciences, Faculty of Science, King Abdulaziz University, Jeddah 21589, Saudi Arabia
| | - Abdullah S Al Mutiri
- Laboratory Department, Saudi Food and Drug Authority, Riyadh 12843, Saudi Arabia
| | - Abdullah M Al-Alyani
- Laboratory Department, Saudi Food and Drug Authority, Jeddah 22311, Saudi Arabia
| | - Mazen S Alseghayer
- Department of Biological Sciences, Faculty of Science, King Abdulaziz University, Jeddah 21589, Saudi Arabia
- Monitoring and Risk Assessment Department, Saudi Food and Drug Authority, Riyadh 13513, Saudi Arabia
| | - Abdulaziz M Almaneea
- Department of Biological Sciences, Faculty of Science, King Abdulaziz University, Jeddah 21589, Saudi Arabia
- Monitoring and Risk Assessment Department, Saudi Food and Drug Authority, Riyadh 13513, Saudi Arabia
| | - Abdulgader H Albar
- Department of Biological Sciences, Faculty of Science, King Abdulaziz University, Jeddah 21589, Saudi Arabia
- Department of Microbiology and Medical Parasitology, Faculty of Medicine, Jeddah University, Jeddah 23218, Saudi Arabia
| | - Mohsen A Khormi
- Department of Biological Sciences, Faculty of Sciences, Jazan University, Jazan 82817, Saudi Arabia
| | - Arun K Bhunia
- Molecular Food Microbiology Laboratory, Department of Food Science, Purdue University, West Lafayette, IN 47907, USA
- Purdue Institute of Inflammation, Immunology, and Infectious Disease, Purdue University, West Lafayette, IN 47907, USA
- Purdue University Interdisciplinary Life Science Program (PULSe), West Lafayette, IN 47907, USA
- Department of Comparative Pathobiology, Purdue University, West Lafayette, IN 47907, USA
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20
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Avraham R. Untangling Cellular Host-Pathogen Encounters at Infection Bottlenecks. Infect Immun 2023; 91:e0043822. [PMID: 36939328 PMCID: PMC10112260 DOI: 10.1128/iai.00438-22] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 03/21/2023] Open
Abstract
Bacterial pathogens can invade the tissue and establish a protected intracellular niche at the site of invasion that can spread locally (e.g., microcolonies) or to systemic sites (e.g., granulomas). Invasion of the tissue and establishment of intracellular infection are rare events that are difficult to study in the in vivo setting but have critical clinical consequences, such as long-term carriage, reinfections, and emergence of antibiotic resistance. Here, I discuss Salmonella interactions with its host macrophage during early stages of infection and their critical role in determining infection outcome. The dynamics of host-pathogen interactions entail highly heterogenous host immunity, bacterial virulence, and metabolic cross talk, requiring in vivo analysis at single-cell resolution. I discuss models and single-cell approaches that provide a global understanding of the establishment of a protected intracellular niche within the tissue and the host-pathogen landscape at infection bottlenecks during early stages of infection. Studying cellular host-pathogen interactions in vivo can improve our knowledge of the trajectory of infection between the initial inoculation with a dose of pathogens and the appearance of symptoms of disease.
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Affiliation(s)
- Roi Avraham
- Department of Immunology and Regenerative Biology, Weizmann Institute of Science, Rehovot, Israel
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21
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Gong J, Cheng X, Zuo J, Zhang Y, Lin J, Liu M, Jiang Y, Long Y, Si H, Gao X, Guo D, Gu N. Silver nanoparticles combat Salmonella Typhimurium: Suppressing intracellular infection and activating dendritic cells. Colloids Surf B Biointerfaces 2023; 226:113307. [PMID: 37068446 DOI: 10.1016/j.colsurfb.2023.113307] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/10/2022] [Revised: 02/16/2023] [Accepted: 04/08/2023] [Indexed: 04/19/2023]
Abstract
Salmonella Typhimurium (ST) can hide inside cells, avoid antibiotic therapy and being killed by host's immune system to cause persistent infection in humans and animals. Metal nanoparticles are regarded as an alternative to overcome the above limitations, silver nanoparticles especially have been applied in combating drug-resistant bacteria. However, the therapeutic effects of silver nanoparticles against intracellular infection and their impacts on host immunity remain an area of further investigation. In this work, we synthesized Ganoderma extract-capped silver nanoparticles (Ag@Ge) and explored the therapeutic potential and immune adjuvant effects of Ag@Ge against intracellular ST. Firstly, Ag@Ge had a small particle size of 35.52±7.46 nm, good stability, and biocompatibility. Then, Ag@Ge effectively entered RAW 264.7 cells, suppressed intracellular ST infection. Furthermore, Ag@Ge activated mouse dendritic cells (DCs) in vitro, evidenced by increased phenotypic markers (CD80/CD86/CD40/major compatibility complex II (MHCII)) expression and cytokine and chemokine (interleukin-6 (IL-6), interleukin-1β (IL-1β), tumor necrosis factor-α (TNF-α), chemokine (C-C motif) ligand 2 (CCL-2), and chemokine (C-C motif) receptor-7 (CCR-7)) transcription. More notably, the combination of Ag@Ge with inactivated ST recruited intestinal DCs to mitigate ST infection in mice, evidenced by decreased body weight loss and bacterial loads in the tissues (liver, jejunum, and colon), and improved platelets count. The above findings indicate that Ag@Ge has the potential as an alternative nano-antibiotic against intracellular ST infection.
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Affiliation(s)
- Jiahao Gong
- Engineering Center of Innovative Veterinary Drugs, Center for Veterinary Drug Research and Evaluation, MOE Joint International Research Laboratory of Animal Health and Food Safety, College of Veterinary Medicine, Nanjing Agricultural University, 1 Weigang, Nanjing 210095, China
| | - Xingxing Cheng
- Engineering Center of Innovative Veterinary Drugs, Center for Veterinary Drug Research and Evaluation, MOE Joint International Research Laboratory of Animal Health and Food Safety, College of Veterinary Medicine, Nanjing Agricultural University, 1 Weigang, Nanjing 210095, China
| | - Jinjiao Zuo
- College of Life Sciences, Nanjing Agricultural University, 1 Weigang, Nanjing 210095, China
| | - Yan Zhang
- Engineering Center of Innovative Veterinary Drugs, Center for Veterinary Drug Research and Evaluation, MOE Joint International Research Laboratory of Animal Health and Food Safety, College of Veterinary Medicine, Nanjing Agricultural University, 1 Weigang, Nanjing 210095, China
| | - Jian Lin
- Engineering Center of Innovative Veterinary Drugs, Center for Veterinary Drug Research and Evaluation, MOE Joint International Research Laboratory of Animal Health and Food Safety, College of Veterinary Medicine, Nanjing Agricultural University, 1 Weigang, Nanjing 210095, China; College of Life Sciences, Nanjing Agricultural University, 1 Weigang, Nanjing 210095, China
| | - Moxin Liu
- Engineering Center of Innovative Veterinary Drugs, Center for Veterinary Drug Research and Evaluation, MOE Joint International Research Laboratory of Animal Health and Food Safety, College of Veterinary Medicine, Nanjing Agricultural University, 1 Weigang, Nanjing 210095, China
| | - Yan Jiang
- Animal, Plant and Food Inspection Center of Nanjing Customs District, 39 Chuangzhi Road, Nanjing 210000, China
| | - Yunfeng Long
- Animal, Plant and Food Inspection Center of Nanjing Customs District, 39 Chuangzhi Road, Nanjing 210000, China
| | - Hongbin Si
- State Key Laboratory for Conservation and Utilization of Subtropical Agro-bioresources, College of Animal Science and Technology, Guangxi University, Nanning 530004, China
| | - Xiuge Gao
- Engineering Center of Innovative Veterinary Drugs, Center for Veterinary Drug Research and Evaluation, MOE Joint International Research Laboratory of Animal Health and Food Safety, College of Veterinary Medicine, Nanjing Agricultural University, 1 Weigang, Nanjing 210095, China
| | - Dawei Guo
- Engineering Center of Innovative Veterinary Drugs, Center for Veterinary Drug Research and Evaluation, MOE Joint International Research Laboratory of Animal Health and Food Safety, College of Veterinary Medicine, Nanjing Agricultural University, 1 Weigang, Nanjing 210095, China.
| | - Ning Gu
- Medical School, Nanjing University, 22 Hankou Road, Nanjing 210093, China
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22
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Yuan H, Zhou L, Chen Y, You J, Hu H, Li Y, Huang R, Wu S. Salmonella effector SopF regulates PANoptosis of intestinal epithelial cells to aggravate systemic infection. Gut Microbes 2023; 15:2180315. [PMID: 36803521 PMCID: PMC9980482 DOI: 10.1080/19490976.2023.2180315] [Citation(s) in RCA: 7] [Impact Index Per Article: 7.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Figures] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Indexed: 02/23/2023] Open
Abstract
SopF, a newly discovered effector secreted by Salmonella pathogenicity island-1 type III secretion system (T3SS1), was reported to target phosphoinositide on host cell membrane and aggravate systemic infection, while its functional relevance and underlying mechanisms have yet to be elucidated. PANoptosis (pyroptosis, apoptosis, and necroptosis) of intestinal epithelial cells (IECs) has been characterized as a pivotal host defense to limit the dissemination of foodborne pathogens, whereas the effect of SopF on IECs PANoptosis induced by Salmonella is rather limited. Here, we show that SopF can attenuate intestinal inflammation and suppress IECs expulsion to promote bacterial dissemination in mice infected with Salmonella enterica serovar Typhimurium (S. Typhimurium). We revealed that SopF could activate phosphoinositide-dependent protein kinase-1 (PDK1) to phosphorylate p90 ribosomal S6 kinase (RSK) which down-regulated Caspase-8 activation. Caspase-8 inactivated by SopF resulted in inhibition of pyroptosis and apoptosis, but promotion of necroptosis. The administration of both AR-12 (PDK1 inhibitor) and BI-D1870 (RSK inhibitor) potentially overcame Caspase-8 blockade and subverted PANoptosis challenged by SopF. Collectively, these findings demonstrate that this virulence strategy elicited by SopF aggregates systemic infection via modulating IEC PANoptosis through PDK1-RSK signaling, which throws light on novel functions of bacterial effectors, as well as a mechanism employed by pathogens to counteract host immune defense.
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Affiliation(s)
- Haibo Yuan
- Department of Medical Microbiology, School of Biology and Basic Medical Science, Suzhou Medical College of Soochow University, Suzhou, China,Department of Medical Technology, Suzhou Vocational Health College, Suzhou, China
| | - Liting Zhou
- Department of Medical Microbiology, School of Biology and Basic Medical Science, Suzhou Medical College of Soochow University, Suzhou, China,Suzhou Key Laboratory of Pathogen Bioscience and Anti-infective Medicine
| | - Yilin Chen
- Department of Medical Microbiology, School of Biology and Basic Medical Science, Suzhou Medical College of Soochow University, Suzhou, China
| | - Jiayi You
- Department of Medical Microbiology, School of Biology and Basic Medical Science, Suzhou Medical College of Soochow University, Suzhou, China
| | - Hongye Hu
- Department of Medical Microbiology, School of Biology and Basic Medical Science, Suzhou Medical College of Soochow University, Suzhou, China
| | - Yuanyuan Li
- Department of Medical Microbiology, School of Biology and Basic Medical Science, Suzhou Medical College of Soochow University, Suzhou, China,Suzhou Key Laboratory of Pathogen Bioscience and Anti-infective Medicine
| | - Rui Huang
- Department of Medical Microbiology, School of Biology and Basic Medical Science, Suzhou Medical College of Soochow University, Suzhou, China,Suzhou Key Laboratory of Pathogen Bioscience and Anti-infective Medicine
| | - Shuyan Wu
- Department of Medical Microbiology, School of Biology and Basic Medical Science, Suzhou Medical College of Soochow University, Suzhou, China,Suzhou Key Laboratory of Pathogen Bioscience and Anti-infective Medicine,CONTACT Shuyan Wu; Rui Huang ; Department of Medical Microbiology, School of Biology and Basic Medical Sciences, Suzhou Medical College of Soochow University, No. 199, Ren Ai Road, Suzhou, Jiangsu215123, PR China
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23
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Däullary T, Imdahl F, Dietrich O, Hepp L, Krammer T, Fey C, Neuhaus W, Metzger M, Vogel J, Westermann AJ, Saliba AE, Zdzieblo D. A primary cell-based in vitro model of the human small intestine reveals host olfactomedin 4 induction in response to Salmonella Typhimurium infection. Gut Microbes 2023; 15:2186109. [PMID: 36939013 PMCID: PMC10038062 DOI: 10.1080/19490976.2023.2186109] [Citation(s) in RCA: 1] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Indexed: 03/21/2023] Open
Abstract
Infection research largely relies on classical cell culture or mouse models. Despite having delivered invaluable insights into host-pathogen interactions, both have limitations in translating mechanistic principles to human pathologies. Alternatives can be derived from modern Tissue Engineering approaches, allowing the reconstruction of functional tissue models in vitro. Here, we combined a biological extracellular matrix with primary tissue-derived enteroids to establish an in vitro model of the human small intestinal epithelium exhibiting in vivo-like characteristics. Using the foodborne pathogen Salmonella enterica serovar Typhimurium, we demonstrated the applicability of our model to enteric infection research in the human context. Infection assays coupled to spatio-temporal readouts recapitulated the established key steps of epithelial infection by this pathogen in our model. Besides, we detected the upregulation of olfactomedin 4 in infected cells, a hitherto unrecognized aspect of the host response to Salmonella infection. Together, this primary human small intestinal tissue model fills the gap between simplistic cell culture and animal models of infection, and shall prove valuable in uncovering human-specific features of host-pathogen interplay.
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Affiliation(s)
- Thomas Däullary
- Chair of Tissue Engineering and Regenerative Medicine, University Hospital Würzburg (UKW), Würzburg, Germany
- Faculty of Biology, Biocenter, Chair of Microbiology, Julius-Maximilians-Universität Würzburg (JMU), Würzburg, Germany
| | - Fabian Imdahl
- Helmholtz-Institute for RNA-based Infection Research (HIRI), Helmholtz Centre for Infection Research (HZI), Würzburg, Germany
| | - Oliver Dietrich
- Helmholtz-Institute for RNA-based Infection Research (HIRI), Helmholtz Centre for Infection Research (HZI), Würzburg, Germany
| | - Laura Hepp
- Chair of Tissue Engineering and Regenerative Medicine, University Hospital Würzburg (UKW), Würzburg, Germany
| | - Tobias Krammer
- Helmholtz-Institute for RNA-based Infection Research (HIRI), Helmholtz Centre for Infection Research (HZI), Würzburg, Germany
| | - Christina Fey
- Fraunhofer Institute for Silicate Research (ISC),Translational Center Regenerative Therapies (TLC-RT), Würzburg, Germany
| | - Winfried Neuhaus
- Austrian Institute of Technology (AIT), Vienna, Austria
- Department of Medicine, Faculty of Medicine and Dentistry, Danube Private University (DPU), Krems, Austria
| | - Marco Metzger
- Chair of Tissue Engineering and Regenerative Medicine, University Hospital Würzburg (UKW), Würzburg, Germany
- Fraunhofer Institute for Silicate Research (ISC),Translational Center Regenerative Therapies (TLC-RT), Würzburg, Germany
- Fraunhofer Institute for Silicate Research, Project Center for Stem Cell Process Engineering, Würzburg, Germany
| | - Jörg Vogel
- Helmholtz-Institute for RNA-based Infection Research (HIRI), Helmholtz Centre for Infection Research (HZI), Würzburg, Germany
- Institute for Molecular Infection Biology (IMIB), University of Würzburg, Würzburg, Germany
| | - Alexander J Westermann
- Helmholtz-Institute for RNA-based Infection Research (HIRI), Helmholtz Centre for Infection Research (HZI), Würzburg, Germany
- Institute for Molecular Infection Biology (IMIB), University of Würzburg, Würzburg, Germany
| | - Antoine-Emmanuel Saliba
- Helmholtz-Institute for RNA-based Infection Research (HIRI), Helmholtz Centre for Infection Research (HZI), Würzburg, Germany
| | - Daniela Zdzieblo
- Chair of Tissue Engineering and Regenerative Medicine, University Hospital Würzburg (UKW), Würzburg, Germany
- Fraunhofer Institute for Silicate Research (ISC),Translational Center Regenerative Therapies (TLC-RT), Würzburg, Germany
- Fraunhofer Institute for Silicate Research, Project Center for Stem Cell Process Engineering, Würzburg, Germany
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24
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Lin Y, Xie Z, Li Z, Yuan C, Zhang C, Li Y, Xie K, Wang K. Assessment of the role and mechanism of Bifidobacterium animalis subsp. lactis isolated from neonates' feces in protecting neonatal rats from Salmonella infection. Microb Pathog 2023; 174:105935. [PMID: 36509312 DOI: 10.1016/j.micpath.2022.105935] [Citation(s) in RCA: 1] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/27/2022] [Revised: 12/05/2022] [Accepted: 12/05/2022] [Indexed: 12/13/2022]
Abstract
OBJECTIVES It is now well known that Bifidobacterium animalis subsp. lactis (B. lactis), an important early-life colonizer of the gut, provides immune-related benefits to infants. The aim of the work is to explore the intraspecific resistance to Salmonella infection of B. lactis isolated from neonatal feces, and to learn more insights into how B. lactis mediates beneficial roles in early-life infection resistance. METHODS Five strains of B. lactis (NFBAL11/NFBAL23/NFBAL44/NFBAL63/NFBAL92) were screened from fecal samples of neonates born within fifteen days and pretreated neonatal rats prior to infection with Salmonella typhimurium (S. typhimurium) SL1344. The survival rate, fecal occult blood, diarrhea and hepatosplenomegaly were detected to assess the ability of B. lactis to prevent S. typhimurium infection. Furthermore, the structure of mucus layer, gene expression, cytokine levels, antioxidant levels and intestinal microflora composition were detected to explore the mechanism. RESULTS All strains showed activity against S. typhimurium, with B. lactis NFBAL23 being the most active, followed by NFBAL63 and NFBAL92. And these advantages weren't attained by enhancing physical growth and development. Mechanistically, the neonatal rats treated with B. lactis (NFBAL23/NFBAL63/NFBAL92) had improved intestinal barrier function involving physical, chemical, immune and biological barriers in the face of challenges posed by S. typhimurium. CONCLUSIONS These findings revealed the intraspecific difference, beneficial roles and mechanisms of action of B. lactis against Salmonella infection early in life, which highlighted the necessity of supplementing appropriate B. lactis, and provided several potential B. lactis candidates for Salmonella infection treatment.
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Affiliation(s)
- Yugui Lin
- Microbiology Laboratory, Zhongshan Bo'ai Hospital, Southern Medical University, 528400, Zhongshan, China; Department of Microbiology, School of Basic Medicine Science, Guangxi Medical University, 530021, Nanning, China.
| | - Zhong Xie
- Department of Microbiology, School of Basic Medicine Science, Guangxi Medical University, 530021, Nanning, China
| | - Zhouyi Li
- Department of Microbiology, School of Basic Medicine Science, Guangxi Medical University, 530021, Nanning, China
| | - Chunlei Yuan
- Microbiology Laboratory, Zhongshan Bo'ai Hospital, Southern Medical University, 528400, Zhongshan, China
| | - Chilun Zhang
- Microbiology Laboratory, Zhongshan Bo'ai Hospital, Southern Medical University, 528400, Zhongshan, China
| | - Yanfen Li
- Microbiology Laboratory, Zhongshan Bo'ai Hospital, Southern Medical University, 528400, Zhongshan, China; Institute of Molecular Immunology, School of Laboratory Medicine and Biotechnology, Southern Medical University, 510515, Guangzhou, China
| | - Kunke Xie
- Immunology Laboratory, Zhongshan Bo'ai Hospital, Southern Medical University, 528400, Zhongshan, China
| | - Ke Wang
- Immunology Laboratory, Zhongshan Bo'ai Hospital, Southern Medical University, 528400, Zhongshan, China
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25
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Di Martino ML, Sellin ME. Barcoded Consortium Infections: A Scalable, Internally Controlled Method to Study Host Cell Binding and Invasion by Pathogenic Bacteria. Methods Mol Biol 2023; 2674:295-311. [PMID: 37258976 DOI: 10.1007/978-1-0716-3243-7_20] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 06/02/2023]
Abstract
Bacterial host cell invasion has routinely been investigated by gentamicin protection assays, which are laborsome and suffer from pronounced experimental noise. This chapter describes an internally controlled, medium- to high-throughput method that resolves the capacity of multiple Salmonella virulence factor mutant strains to bind and invade host cells. The method, widely applicable to also other pathogens, is based on the combination of consortia of genetically tagged isogenic bacterial strains and a modified gentamicin protection assay. These protocols provide a flexible tool box to stringently quantify host cell binding and invasive properties of different mutants. Moreover, the method can be applied to both infections of cultured host cells and in vivo animal models, providing a comparable genetic readout, which greatly facilitates comparisons across experimental models.
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Affiliation(s)
- Maria Letizia Di Martino
- Science for Life Laboratory, Department of Medical Biochemistry and Microbiology, Uppsala University, Uppsala, Sweden.
| | - Mikael E Sellin
- Science for Life Laboratory, Department of Medical Biochemistry and Microbiology, Uppsala University, Uppsala, Sweden.
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26
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Felipe-López A, Hansmeier N, Danzer C, Hensel M. Manipulation of microvillar proteins during Salmonella enterica invasion results in brush border effacement and actin remodeling. Front Cell Infect Microbiol 2023; 13:1137062. [PMID: 36936760 PMCID: PMC10018140 DOI: 10.3389/fcimb.2023.1137062] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/03/2023] [Accepted: 02/10/2023] [Indexed: 03/06/2023] Open
Abstract
Enterocyte invasion by the gastrointestinal pathogen Salmonella enterica is accompanied by loss of brush border and massive remodeling of the actin cytoskeleton, leading to microvilli effacement and formation of membrane ruffles. These manipulations are mediated by effector proteins translocated by the Salmonella Pathogenicity Island 1-encoded type III secretion system (SPI1-T3SS). To unravel the mechanisms of microvilli effacement and contribution of SPI1-T3SS effector proteins, the dynamics of host-pathogen interactions was analyzed using live cell imaging (LCI) of polarized epithelial cells (PEC) expressing LifeAct-GFP. PEC were infected with S. enterica wild-type and mutant strains with defined defects in SPI1-T3SS effector proteins, and pharmacological inhibition of actin assembly were applied. We identified that microvilli effacement involves two distinct mechanisms: i) F-actin depolymerization mediated by villin and ii), the consumption of cytoplasmic G-actin by formation of membrane ruffles. By analyzing the contribution of individual SPI1-T3SS effector proteins, we demonstrate that SopE dominantly triggers microvilli effacement and formation of membrane ruffles. Furthermore, SopE via Rac1 indirectly manipulates villin, which culminates in F-actin depolymerization. Collectively, these results indicate that SopE has dual functions during F-actin remodeling in PEC. While SopE-Rac1 triggers F-actin polymerization and ruffle formation, activation of PLCγ and villin by SopE depolymerizes F-actin in PEC. These results demonstrate the key role of SopE in destruction of the intestinal barrier during intestinal infection by Salmonella.
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Affiliation(s)
| | | | - Claudia Danzer
- Mikrobiologisches Institut, Universitätsklinikum Erlangen, Erlangen, Germany
| | - Michael Hensel
- Abt. Mikrobiologie, Universität Osnabrück, Osnabrück, Germany
- *Correspondence: Michael Hensel,
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27
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Wang M, Xiong D, Wang X, Gu D, Meng C, Jiao X, Pan Z. The DNA adenine methylase of Salmonella Enteritidis promotes their intracellular replication by inhibiting arachidonic acid metabolism pathway in macrophages. Front Microbiol 2023; 14:1080851. [PMID: 36937256 PMCID: PMC10018194 DOI: 10.3389/fmicb.2023.1080851] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/26/2022] [Accepted: 01/23/2023] [Indexed: 03/06/2023] Open
Abstract
Macrophages can participate in immune responses by altering their metabolism, and play important roles in controlling bacterial infections. However, Salmonella Enteritidis can survive and proliferate in macrophages. After the deletion of DNA adenine methylase (Dam), the proliferation of Salmonella Enteritidis in macrophages decreased, the molecular mechanism is still unclear. After infecting macrophages with Salmonella Enteritidis wild type and dam gene deletion strains, intracellular metabolites were extracted and detected by non-targeted metabolomics and fatty acid targeted metabolomics. We found Dam had significant effects on arachidonic acid and related metabolic pathways in macrophages. The dam gene can promote the proliferation of Salmonella Enteritidis in macrophages by inhibiting the metabolic pathway of cytosolic phospholipase A2-mediated arachidonic acid production and conversion to prostaglandin E2 in macrophages, reducing the secretion of the pro-inflammatory factors IL-1β and IL-6. In addition, inhibition of arachidonic acid-related pathways in macrophages by Arachidonyl trifluoromethyl ketone could restore the proliferation of dam gene deletion strains in macrophages. This study explored the role of Dam in the process of Salmonella Enteritidis invading host cells from the perspective of host cell metabolism, and provides new insights into the immune escape mechanism of Salmonella Enteritidis.
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Affiliation(s)
- Ming Wang
- Jiangsu Key Laboratory of Zoonosis, Yangzhou University, Yangzhou, Jiangsu, China
- Jiangsu Co-innovation Center for Prevention and Control of Important Animal Infectious Diseases and Zoonoses, Yangzhou University, Yangzhou, Jiangsu, China
- Key Laboratory of Prevention and Control of Biological Hazard Factors (Animal Origin) for Agrifood Safety and Quality, Ministry of Agriculture and Rural Affairs, Yangzhou University, Yangzhou, Jiangsu, China
- Joint International Research Laboratory of Agriculture and Agri-product Safety of the Ministry of Education, Yangzhou University, Yangzhou, China
| | - Dan Xiong
- Jiangsu Key Laboratory of Zoonosis, Yangzhou University, Yangzhou, Jiangsu, China
- Jiangsu Co-innovation Center for Prevention and Control of Important Animal Infectious Diseases and Zoonoses, Yangzhou University, Yangzhou, Jiangsu, China
- Key Laboratory of Prevention and Control of Biological Hazard Factors (Animal Origin) for Agrifood Safety and Quality, Ministry of Agriculture and Rural Affairs, Yangzhou University, Yangzhou, Jiangsu, China
- Joint International Research Laboratory of Agriculture and Agri-product Safety of the Ministry of Education, Yangzhou University, Yangzhou, China
| | - Xinwei Wang
- Jiangsu Key Laboratory of Zoonosis, Yangzhou University, Yangzhou, Jiangsu, China
- Jiangsu Co-innovation Center for Prevention and Control of Important Animal Infectious Diseases and Zoonoses, Yangzhou University, Yangzhou, Jiangsu, China
- Key Laboratory of Prevention and Control of Biological Hazard Factors (Animal Origin) for Agrifood Safety and Quality, Ministry of Agriculture and Rural Affairs, Yangzhou University, Yangzhou, Jiangsu, China
- Joint International Research Laboratory of Agriculture and Agri-product Safety of the Ministry of Education, Yangzhou University, Yangzhou, China
| | - Dan Gu
- Jiangsu Key Laboratory of Zoonosis, Yangzhou University, Yangzhou, Jiangsu, China
- Jiangsu Co-innovation Center for Prevention and Control of Important Animal Infectious Diseases and Zoonoses, Yangzhou University, Yangzhou, Jiangsu, China
- Key Laboratory of Prevention and Control of Biological Hazard Factors (Animal Origin) for Agrifood Safety and Quality, Ministry of Agriculture and Rural Affairs, Yangzhou University, Yangzhou, Jiangsu, China
- Joint International Research Laboratory of Agriculture and Agri-product Safety of the Ministry of Education, Yangzhou University, Yangzhou, China
| | - Chuang Meng
- Jiangsu Key Laboratory of Zoonosis, Yangzhou University, Yangzhou, Jiangsu, China
- Jiangsu Co-innovation Center for Prevention and Control of Important Animal Infectious Diseases and Zoonoses, Yangzhou University, Yangzhou, Jiangsu, China
- Key Laboratory of Prevention and Control of Biological Hazard Factors (Animal Origin) for Agrifood Safety and Quality, Ministry of Agriculture and Rural Affairs, Yangzhou University, Yangzhou, Jiangsu, China
- Joint International Research Laboratory of Agriculture and Agri-product Safety of the Ministry of Education, Yangzhou University, Yangzhou, China
| | - Xinan Jiao
- Jiangsu Key Laboratory of Zoonosis, Yangzhou University, Yangzhou, Jiangsu, China
- Jiangsu Co-innovation Center for Prevention and Control of Important Animal Infectious Diseases and Zoonoses, Yangzhou University, Yangzhou, Jiangsu, China
- Key Laboratory of Prevention and Control of Biological Hazard Factors (Animal Origin) for Agrifood Safety and Quality, Ministry of Agriculture and Rural Affairs, Yangzhou University, Yangzhou, Jiangsu, China
- Joint International Research Laboratory of Agriculture and Agri-product Safety of the Ministry of Education, Yangzhou University, Yangzhou, China
- *Correspondence: Xinan Jiao,
| | - Zhiming Pan
- Jiangsu Key Laboratory of Zoonosis, Yangzhou University, Yangzhou, Jiangsu, China
- Jiangsu Co-innovation Center for Prevention and Control of Important Animal Infectious Diseases and Zoonoses, Yangzhou University, Yangzhou, Jiangsu, China
- Key Laboratory of Prevention and Control of Biological Hazard Factors (Animal Origin) for Agrifood Safety and Quality, Ministry of Agriculture and Rural Affairs, Yangzhou University, Yangzhou, Jiangsu, China
- Joint International Research Laboratory of Agriculture and Agri-product Safety of the Ministry of Education, Yangzhou University, Yangzhou, China
- Zhiming Pan,
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28
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Boulanger EF, Sabag-Daigle A, Baniasad M, Kokkinias K, Schwieters A, Wrighton KC, Wysocki VH, Ahmer BMM. Sugar-Phosphate Toxicities Attenuate Salmonella Fitness in the Gut. J Bacteriol 2022; 204:e0034422. [PMID: 36383008 PMCID: PMC9765134 DOI: 10.1128/jb.00344-22] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/10/2022] [Accepted: 10/21/2022] [Indexed: 11/17/2022] Open
Abstract
Pathogens are becoming resistant to antimicrobials at an increasing rate, and novel therapeutic strategies are needed. Using Salmonella as a model, we have investigated the induction of sugar-phosphate toxicity as a potential therapeutic modality. The approach entails providing a nutrient while blocking the catabolism of that nutrient, resulting in the accumulation of a toxic intermediate. We hypothesize that this build-up will decrease the fitness of the organism during infection given nutrient availability. We tested this hypothesis using mutants lacking one of seven genes whose mutation is expected to cause the accumulation of a toxic metabolic intermediate. The araD, galE, rhaD, glpD, mtlD, manA, and galT mutants were then provided the appropriate sugars, either in vitro or during gastrointestinal infection of mice. All but the glpD mutant had nutrient-dependent growth defects in vitro, suggestive of sugar-phosphate toxicity. During gastrointestinal infection of mice, five mutants had decreased fitness. Providing the appropriate nutrient in the animal's drinking water was required to cause fitness defects with the rhaD and manA mutants and to enhance the fitness defect of the araD mutant. The galE and mtlD mutants were severely attenuated regardless of the nutrient being provided in the drinking water. Homologs of galE are widespread among bacteria and in humans, rendering the specific targeting of bacterial pathogens difficult. However, the araD, mtlD, and rhaD genes are not present in humans, appear to be rare in most phyla of bacteria, and are common in several genera of Enterobacteriaceae, making the encoded enzymes potential narrow-spectrum therapeutic targets. IMPORTANCE Bacterial pathogens are becoming increasingly resistant to antibiotics. There is an urgent need to identify novel drug targets and therapeutic strategies. In this work we have assembled and characterized a collection of mutations in our model pathogen, Salmonella enterica, that block a variety of sugar utilization pathways in such a way as to cause the accumulation of a toxic sugar-phosphate. Mutations in three genes, rhaD, araD, and mtlD, dramatically decrease the fitness of Salmonella in a mouse model of gastroenteritis, suggesting that RhaD, AraD, and MtlD may be good narrow-spectrum drug targets. The induction of sugar-phosphate toxicities may be a therapeutic strategy that is broadly relevant to other bacterial and fungal pathogens.
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Affiliation(s)
- Erin F. Boulanger
- Department of Microbial Infection and Immunity, The Ohio State University, Columbus, Ohio, USA
| | - Anice Sabag-Daigle
- Department of Microbial Infection and Immunity, The Ohio State University, Columbus, Ohio, USA
| | - Maryam Baniasad
- Department of Chemistry and Biochemistry, The Ohio State University, Columbus, Ohio, USA
| | - Katherine Kokkinias
- Department of Soil and Crop Science, Colorado State University, Ft. Collins, Colorado, USA
| | - Andrew Schwieters
- Department of Microbiology, The Ohio State University, Columbus, Ohio, USA
| | - Kelly C. Wrighton
- Department of Soil and Crop Science, Colorado State University, Ft. Collins, Colorado, USA
| | - Vicki H. Wysocki
- Department of Chemistry and Biochemistry, The Ohio State University, Columbus, Ohio, USA
| | - Brian M. M. Ahmer
- Department of Microbial Infection and Immunity, The Ohio State University, Columbus, Ohio, USA
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Newson JP, Gaissmaier MS, McHugh SC, Hardt WD. Studying antibiotic persistence in vivo using the model organism Salmonella Typhimurium. Curr Opin Microbiol 2022; 70:102224. [PMID: 36335713 DOI: 10.1016/j.mib.2022.102224] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/23/2022] [Revised: 09/22/2022] [Accepted: 10/02/2022] [Indexed: 11/06/2022]
Abstract
Antibiotic persistence permits a subpopulation of susceptible bacteria to survive lethal concentrations of bactericidal antibiotics. This prolongs antibiotic therapy, promotes the evolution of antibiotic-resistant pathogen strains and can select for pathogen virulence within infected hosts. Here, we review the literature exploring antibiotic persistence in vivo, and describe the consequences of recalcitrant subpopulations, with a focus on studies using the model pathogen Salmonella Typhimurium. In vitro studies have established a concise set of features distinguishing true persisters from other forms of bacterial recalcitrance to bactericidal antibiotics. We discuss how animal infection models are useful for exploring these features in vivo, and describe how technical challenges can sometimes prevent the conclusive identification of true antibiotic persistence within infected hosts. We propose using two complementary working definitions for studying antibiotic persistence in vivo: the strict definition for studying the mechanisms of persister formation, and an operative definition for functional studies assessing the links between invasive virulence and persistence as well as the consequences for horizontal gene transfer, or the emergence of antibiotic-resistant mutants. This operative definition will enable further study of how antibiotic persisters arise in vivo, and of how surviving populations contribute to diverse downstream effects such as pathogen transmission, horizontal gene transfer and the evolution of virulence and antibiotic resistance. Ultimately, such studies will help to improve therapeutic control of antibiotic- recalcitrant populations.
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Affiliation(s)
- Joshua Pm Newson
- Institute of Microbiology, Department of Biology, ETH Zürich, Zürich, Switzerland
| | - Marla S Gaissmaier
- Institute of Microbiology, Department of Biology, ETH Zürich, Zürich, Switzerland
| | - Sarah C McHugh
- Department of Fundamental Microbiology, University of Lausanne, Lausanne, Switzerland
| | - Wolf-Dietrich Hardt
- Institute of Microbiology, Department of Biology, ETH Zürich, Zürich, Switzerland.
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30
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Ménard S, Lacroix-Lamandé S, Ehrhardt K, Yan J, Grassl GA, Wiedemann A. Cross-Talk Between the Intestinal Epithelium and Salmonella Typhimurium. Front Microbiol 2022; 13:906238. [PMID: 35733975 PMCID: PMC9207452 DOI: 10.3389/fmicb.2022.906238] [Citation(s) in RCA: 8] [Impact Index Per Article: 4.0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/28/2022] [Accepted: 05/13/2022] [Indexed: 11/13/2022] Open
Abstract
Salmonella enterica serovars are invasive gram-negative bacteria, causing a wide range of diseases from gastroenteritis to typhoid fever, representing a public health threat around the world. Salmonella gains access to the intestinal lumen after oral ingestion of contaminated food or water. The crucial initial step to establish infection is the interaction with the intestinal epithelium. Human-adapted serovars such as S. Typhi or S. Paratyphi disseminate to systemic organs and induce life-threatening disease known as typhoid fever, whereas broad-host serovars such as S. Typhimurium usually are limited to the intestine and responsible for gastroenteritis in humans. To overcome intestinal epithelial barrier, Salmonella developed mechanisms to induce cellular invasion, intracellular replication and to face host defence mechanisms. Depending on the serovar and the respective host organism, disease symptoms differ and are linked to the ability of the bacteria to manipulate the epithelial barrier for its own profit and cross the intestinal epithelium.This review will focus on S. Typhimurium (STm). To better understand STm pathogenesis, it is crucial to characterize the crosstalk between STm and the intestinal epithelium and decipher the mechanisms and epithelial cell types involved. Thus, the purpose of this review is to summarize our current knowledge on the molecular dialogue between STm and the various cell types constituting the intestinal epithelium with a focus on the mechanisms developed by STm to cross the intestinal epithelium and access to subepithelial or systemic sites and survive host defense mechanisms.
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Affiliation(s)
- Sandrine Ménard
- IRSD - Institut de Recherche en Santé Digestive, Université́ de Toulouse, INSERM, INRAE, ENVT, UPS, Toulouse, France
| | | | - Katrin Ehrhardt
- Institute of Medical Microbiology and Hospital Epidemiology, Hannover Medical School and German Center for Infection Research (DZIF), Hannover, Germany
| | - Jin Yan
- IRSD - Institut de Recherche en Santé Digestive, Université́ de Toulouse, INSERM, INRAE, ENVT, UPS, Toulouse, France
- Department of Gastroenterology, The Second Xiangya Hospital of Central South University, Changsha, China
- Research Center of Digestive Disease, Central South University, Changsha, China
| | - Guntram A. Grassl
- Institute of Medical Microbiology and Hospital Epidemiology, Hannover Medical School and German Center for Infection Research (DZIF), Hannover, Germany
| | - Agnès Wiedemann
- IRSD - Institut de Recherche en Santé Digestive, Université́ de Toulouse, INSERM, INRAE, ENVT, UPS, Toulouse, France
- *Correspondence: Agnès Wiedemann,
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31
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Sharma A, Raman V, Lee J, Forbes NS. Microbial Imbalance Induces Inflammation by Promoting Salmonella Penetration through the Mucosal Barrier. ACS Infect Dis 2022; 8:969-981. [PMID: 35404574 DOI: 10.1021/acsinfecdis.1c00530] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/30/2022]
Abstract
The balance of microbial species in the intestine must be maintained to prevent inflammation and disease. Healthy bacteria suppress infection by pathogens and prevent disorders such as inflammatory bowel diseases (IBDs). The role of mucus in the relation between pathogens and the intestinal microbiota is poorly understood. Here, we hypothesized that healthy bacteria inhibit infection by preventing pathogens from penetrating the mucus layer and that microbial imbalance leads to inflammation by promoting the penetration of the mucosal barrier. We tested this hypothesis with an in vitro model that contains mucus, an epithelial cell layer, and resident immune cells. We found that, unlike probiotic VSL#3 bacteria, Salmonella penetrated the mucosal layers and induced the production of interleukin-8 (IL-8) and tumor necrosis factor (TNF)-α. At ratios greater than 104:1, probiotic bacteria suppressed the growth and penetration of Salmonella and reduced the production of inflammatory cytokines. Counterintuitively, low densities of healthy bacteria increased both pathogen penetration and cytokine production. In all cases, mucus increased Salmonella penetration and the production of cytokines. These results suggest that mucus lessens the protective effect of probiotic bacteria by promoting barrier penetration. In this model, a more imbalanced microbial population caused infection and inflammation by selecting pathogens that are more invasive and immunogenic. Combined, the results suggest that the depletion of commensal bacteria or an insufficient dosage of probiotics could worsen an infection and cause increased inflammation. A better understanding of the interactions between pathogens, healthy microbes, and the mucosal barrier will improve the treatment of infections and inflammatory diseases.
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Affiliation(s)
- Abhinav Sharma
- Department of Chemical Engineering, University of Massachusetts, Amherst, Massachusetts 01003, United States
| | - Vishnu Raman
- Department of Chemical Engineering, University of Massachusetts, Amherst, Massachusetts 01003, United States
| | - Jungwoo Lee
- Department of Chemical Engineering, University of Massachusetts, Amherst, Massachusetts 01003, United States
- Molecular and Cellular Biology Graduate Program, University of Massachusetts, Amherst, Massachusetts 01003, United States
- Institute for Applied Life Sciences, University of Massachusetts, Amherst, Massachusetts 01003, United States
| | - Neil S. Forbes
- Department of Chemical Engineering, University of Massachusetts, Amherst, Massachusetts 01003, United States
- Molecular and Cellular Biology Graduate Program, University of Massachusetts, Amherst, Massachusetts 01003, United States
- Institute for Applied Life Sciences, University of Massachusetts, Amherst, Massachusetts 01003, United States
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Ek V, Fattinger SA, Florbrant A, Hardt WD, Di Martino ML, Eriksson J, Sellin ME. A Motile Doublet Form of Salmonella Typhimurium Diversifies Target Search Behaviour at the Epithelial Surface. Mol Microbiol 2022; 117:1156-1172. [PMID: 35332598 PMCID: PMC9325389 DOI: 10.1111/mmi.14898] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/04/2021] [Revised: 02/24/2022] [Accepted: 03/21/2022] [Indexed: 12/01/2022]
Abstract
The behaviors of infectious bacteria are commonly studied in bulk. This is effective to define the general properties of a given isolate, but insufficient to resolve subpopulations and unique single‐microbe behaviors within the bacterial pool. We here employ microscopy to study single‐bacterium characteristics among Salmonella enterica serovar Typhimurium (S.Tm), as they prepare for and launch invasion of epithelial host cells. We find that during the bacterial growth cycle, S.Tm populations switch gradually from fast planktonic growth to a host cell‐invasive phenotype, characterized by flagellar motility and expression of the Type‐three‐secretion‐system‐1. The indistinct nature of this shift leads to the establishment of a transient subpopulation of S.Tm “doublets”—waist‐bearing bacteria anticipating cell division—which simultaneously express host cell invasion machinery. In epithelial cell culture infections, these S.Tm doublets outperform their “singlet” brethren and represent a hyperinvasive subpopulation. Atop both glass and enteroid‐derived monolayers, doublets swim along markedly straighter trajectories than singlets, thereby diversifying search patterns and improving the surface exploration capacity of the total bacterial population. The straighter swimming, combined with an enhanced cell‐adhesion propensity, suffices to account for the hyperinvasive doublet phenotype. This work highlights bacterial cell length heterogeneity as a key determinant of target search patterns atop epithelia.
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Affiliation(s)
- Viktor Ek
- Science for Life Laboratory, Department of Medical Biochemistry and Microbiology, Uppsala University, Sweden
| | - Stefan A Fattinger
- Science for Life Laboratory, Department of Medical Biochemistry and Microbiology, Uppsala University, Sweden.,Institute of Microbiology, Department of Biology, ETH, Zurich, Zurich, Switzerland
| | - Alexandra Florbrant
- Science for Life Laboratory, Department of Medical Biochemistry and Microbiology, Uppsala University, Sweden
| | - Wolf-Dietrich Hardt
- Institute of Microbiology, Department of Biology, ETH, Zurich, Zurich, Switzerland
| | - Maria Letizia Di Martino
- Science for Life Laboratory, Department of Medical Biochemistry and Microbiology, Uppsala University, Sweden
| | - Jens Eriksson
- Science for Life Laboratory, Department of Medical Biochemistry and Microbiology, Uppsala University, Sweden
| | - Mikael E Sellin
- Science for Life Laboratory, Department of Medical Biochemistry and Microbiology, Uppsala University, Sweden
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Sibinelli-Sousa S, de Araújo-Silva AL, Hespanhol JT, Bayer-Santos E. Revisiting the steps of Salmonella gut infection with a focus on antagonistic interbacterial interactions. FEBS J 2021; 289:4192-4211. [PMID: 34546626 DOI: 10.1111/febs.16211] [Citation(s) in RCA: 13] [Impact Index Per Article: 4.3] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/15/2021] [Revised: 09/12/2021] [Accepted: 09/20/2021] [Indexed: 12/20/2022]
Abstract
A commensal microbial community is established in the mammalian gut during its development, and these organisms protect the host against pathogenic invaders. The hallmark of noninvasive Salmonella gut infection is the induction of inflammation via effector proteins secreted by the type III secretion system, which modulate host responses to create a new niche in which the pathogen can overcome the colonization resistance imposed by the microbiota. Several studies have shown that endogenous microbes are important to control Salmonella infection by competing for resources. However, there is limited information about antimicrobial mechanisms used by commensals and pathogens during these in vivo disputes for niche control. This review aims to revisit the steps that Salmonella needs to overcome during gut colonization-before and after the induction of inflammation-to achieve an effective infection. We focus on a series of reported and hypothetical antagonistic interbacterial interactions in which both contact-independent and contact-dependent mechanisms might define the outcome of the infection.
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Affiliation(s)
| | | | - Julia Takuno Hespanhol
- Departamento de Microbiologia, Instituto de Ciências Biomédicas, Universidade de São Paulo, Brazil
| | - Ethel Bayer-Santos
- Departamento de Microbiologia, Instituto de Ciências Biomédicas, Universidade de São Paulo, Brazil
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High-Definition DIC Imaging Uncovers Transient Stages of Pathogen Infection Cycles on the Surface of Human Adult Stem Cell-Derived Intestinal Epithelium. mBio 2021; 13:e0002222. [PMID: 35100876 PMCID: PMC8805028 DOI: 10.1128/mbio.00022-22] [Citation(s) in RCA: 4] [Impact Index Per Article: 1.3] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/18/2022] Open
Abstract
Interactions between individual pathogenic microbes and host tissues involve fast and dynamic processes that ultimately impact the outcome of infection. Using live-cell microscopy, these dynamics can be visualized to study, e.g., microbe motility, binding and invasion of host cells, and intrahost-cell survival. Such methodology typically employs confocal imaging of fluorescent tags in tumor-derived cell line infections on glass. This allows high-definition imaging but poorly reflects the host tissue's physiological architecture and may result in artifacts. We developed a method for live-cell imaging of microbial infection dynamics on human adult stem cell-derived intestinal epithelial cell (IEC) layers. These IEC layers are grown in apical imaging chambers, optimized for physiological cell arrangement and fast, but gentle, differential interference contrast (DIC) imaging. This allows subsecond visualization of both microbial and epithelial surface ultrastructure at high resolution without using fluorescent reporters. We employed this technology to probe the behavior of two model pathogens, Salmonella enterica serovar Typhimurium and Giardia intestinalis, at the intestinal epithelial surface. Our results reveal pathogen-specific swimming patterns on the epithelium and show that Salmonella lingers on the IEC surface for prolonged periods before host cell invasion, while Giardia uses circular swimming with intermittent attachments to scout for stable adhesion sites. The method even permits tracking of individual Giardia flagella, demonstrating that active flagellar beating and attachment to the IEC surface are not mutually exclusive. This work describes a generalizable and relatively inexpensive approach to resolving dynamic pathogen-IEC layer interactions, applicable even to genetically nontractable microorganisms. IMPORTANCE Knowledge of dynamic niche-specific interactions between single microbes and host cells is essential to understand infectious disease progression. However, advances in this field have been hampered by the inherent conflict between the technical requirements for high-resolution live-cell imaging on the one hand and conditions that best mimic physiological infection niche parameters on the other. Toward bridging this divide, we present a methodology for differential interference contrast (DIC) imaging of pathogen interactions at the apical surface of enteroid-derived intestinal epithelia, providing both high spatial and temporal resolution. This alleviates the need for fluorescent reporters in live-cell imaging and provides dynamic information about microbe interactions with a nontransformed, confluent, polarized, and microvilliated human gut epithelium. Using this methodology, we uncover previously unrecognized stages of Salmonella and Giardia infection cycles at the epithelial surface.
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