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Chowdhury R, Pavinski Bitar PD, Chapman HM, Altier C. Salmonella Invasion Is Controlled by Competition among Intestinal Chemical Signals. mBio 2023; 14:e0001223. [PMID: 37017539 PMCID: PMC10127606 DOI: 10.1128/mbio.00012-23] [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: 01/02/2023] [Accepted: 03/14/2023] [Indexed: 04/06/2023] Open
Abstract
The intestine is a complex, ever-changing environment replete with an array of signaling molecules. To colonize such a complex organ, pathogens have adapted to utilize specific cues from the local environment to intricately regulate the expression of their virulence determinants. Salmonella preferentially colonizes the distal ileum, a niche enriched in the metabolite formic acid. Here, we show that the relatively higher concentration of this metabolite in the distal ileum prevents other signals from repressing Salmonella invasion in that region. We show that imported and unmetabolized formic acid functions as a cytoplasmic signal that competitively binds to HilD, the master transcriptional regulator of Salmonella invasion, thus preventing repressive fatty acids from binding to the protein. This results in an increased lifetime of HilD and subsequent derepression of invasion genes. This study demonstrates an important mechanism by which Salmonella utilizes competition among signals in the gut to its advantage as a pathogen. IMPORTANCE Enteric pathogens acutely sense their environment for signals to regulate their virulence functions. We demonstrate here that the enteric pathogen Salmonella utilizes the competition among certain regional intestinal constituents to modulate its virulence determinants in that region. We show that the high concentration of formic acid in the ileum outcompetes other signals and triggers the activation of virulence genes in the ileum. This study shows a delicate spatial and temporal mechanism by which enteric pathogens may utilize the competition among environmental cues to optimize their pathogenicity.
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Affiliation(s)
- Rimi Chowdhury
- Department of Population Medicine and Diagnostic Sciences, Cornell University, Ithaca, New York, USA
| | - Paulina D. Pavinski Bitar
- Department of Population Medicine and Diagnostic Sciences, Cornell University, Ithaca, New York, USA
| | - Hanora M. Chapman
- Department of Population Medicine and Diagnostic Sciences, Cornell University, Ithaca, New York, USA
| | - Craig Altier
- Department of Population Medicine and Diagnostic Sciences, Cornell University, Ithaca, New York, USA
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2
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Mitchell MK, Ellermann M. Long Chain Fatty Acids and Virulence Repression in Intestinal Bacterial Pathogens. Front Cell Infect Microbiol 2022; 12:928503. [PMID: 35782143 PMCID: PMC9247172 DOI: 10.3389/fcimb.2022.928503] [Citation(s) in RCA: 9] [Impact Index Per Article: 4.5] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/25/2022] [Accepted: 05/23/2022] [Indexed: 11/13/2022] Open
Abstract
When bacterial pathogens enter the gut, they encounter a complex milieu of signaling molecules and metabolites produced by host and microbial cells or derived from external sources such as the diet. This metabolomic landscape varies throughout the gut, thus establishing a biogeographical gradient of signals that may be sensed by pathogens and resident bacteria alike. Enteric bacterial pathogens have evolved elaborate mechanisms to appropriately regulate their virulence programs, which involves sensing and responding to many of these gut metabolites to facilitate successful gut colonization. Long chain fatty acids (LCFAs) represent major constituents of the gut metabolome that can impact bacterial functions. LCFAs serve as important nutrient sources for all cellular organisms and can function as signaling molecules that regulate bacterial metabolism, physiology, and behaviors. Moreover, in several enteric pathogens, including Salmonella enterica, Listeria monocytogenes, Vibrio cholerae, and enterohemorrhagic Escherichia coli, LCFA sensing results in the transcriptional repression of virulence through two general mechanisms. First, some LCFAs function as allosteric inhibitors that decrease the DNA binding affinities of transcriptional activators of virulence genes. Second, some LCFAs also modulate the activation of histidine kinase receptors, which alters downstream intracellular signaling networks to repress virulence. This mini-review will summarize recent studies that have investigated the molecular mechanisms by which different LCFA derivatives modulate the virulence of enteric pathogens, while also highlighting important gaps in the field regarding the roles of LCFAs as determinants of infection and disease.
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3
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Thomasen RSS, Jespersen MG, Jørgensen K, Dos Santos PT, Sternkopf Lillebæk EM, Skov MN, Kemp M, Kallipolitis BH. The Global Regulator CcpA of Listeria monocytogenes Confers Sensitivity to Antimicrobial Fatty Acids. Front Microbiol 2022; 13:895942. [PMID: 35591996 PMCID: PMC9113694 DOI: 10.3389/fmicb.2022.895942] [Citation(s) in RCA: 2] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/14/2022] [Accepted: 04/15/2022] [Indexed: 11/25/2022] Open
Abstract
Free fatty acids (FFAs) are known to exhibit antimicrobial and anti-virulent properties against bacterial pathogens. Specific FFAs, such as lauric acid (LA; C12:0), exert both effects against the foodborne pathogen Listeria monocytogenes: at low levels, LA acts to inhibit the activity of the virulence regulator PrfA, whereas at higher levels, LA inhibits bacterial growth. Deletion of prfA is known to promote tolerance toward antimicrobial FFAs, suggesting that the response of L. monocytogenes to anti-virulent and antimicrobial FFAs could be linked. In this study, we explored the response of L. monocytogenes toward antimicrobial FFAs holding an anti-virulence activity by isolating strains that can grow at high concentrations of LA. We found that LA-tolerant isolates carry mutations in the gene encoding the global regulator CcpA. Importantly, we discovered that mutation or deletion of ccpA protect L. monocytogenes against the antimicrobial activity of FFAs, whereas the ccpA mutants remain sensitive toward FFA’s PrfA inhibitory effect. A regulatory link involving CcpA, connecting the response toward the antimicrobial and anti-virulence activities of FFAs, is therefore unlikely. To further study how deletion of ccpA promotes FFA tolerance, we performed a transcriptomic analysis of the response to LA. Our data indicated that the FFA-tolerant phenotype of the ∆ccpA strain is not induced upon LA exposure but appears to be an inherent phenotypic trait of the ccpA deletion mutation. Interestingly, we found that the bacterial surface of L. monocytogenes becomes more hydrophilic upon deletion of ccpA, and we demonstrate that CcpA plays a role in the response of L. monocytogenes to other stress conditions, including low pH and antibiotics. Altogether, our study revealed that regulatory activities of CcpA lead to an increased hydrophobicity of the bacterial surface, which may confer sensitivity of L. monocytogenes against the antimicrobial activity of FFAs. Notably, CcpA is not involved in responding to the PrfA inhibitory effect of FFAs, showing that FFA-tolerant strains can still be targeted by the anti-virulent activity of FFAs.
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Affiliation(s)
- Rikke S S Thomasen
- Department of Biochemistry and Molecular Biology, University of Southern Denmark, Odense, Denmark
| | - Magnus Ganer Jespersen
- Department of Biochemistry and Molecular Biology, University of Southern Denmark, Odense, Denmark.,Department of Microbiology and Immunology, The Peter Doherty Institute for Infection and Immunity, University of Melbourne, Melbourne, VIC, Australia
| | - Katrine Jørgensen
- Department of Biochemistry and Molecular Biology, University of Southern Denmark, Odense, Denmark
| | - Patricia T Dos Santos
- Department of Biochemistry and Molecular Biology, University of Southern Denmark, Odense, Denmark.,National Food Institute, Technical University of Denmark, Kgs. Lyngby, Denmark
| | - Eva M Sternkopf Lillebæk
- Department of Biochemistry and Molecular Biology, University of Southern Denmark, Odense, Denmark
| | - Marianne N Skov
- Department of Clinical Microbiology, Odense University Hospital and Research Unit of Clinical Microbiology, University of Southern Denmark, Odense, Denmark
| | - Michael Kemp
- Department of Clinical Microbiology, Odense University Hospital and Research Unit of Clinical Microbiology, University of Southern Denmark, Odense, Denmark.,The Regional Department of Clinical Microbiology, Region Zealand, Zealand University Hospital, Koege, Denmark
| | - Birgitte H Kallipolitis
- Department of Biochemistry and Molecular Biology, University of Southern Denmark, Odense, Denmark
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4
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Thomasen RSS, dos Santos PT, Sternkopf Lillebæk EM, Skov MN, Kemp M, Kallipolitis BH. Absence of N-Acetylglucosamine Glycosylation on Listeria monocytogenes Wall Teichoic Acids Promotes Fatty Acid Tolerance by Repulsion From the Bacterial Surface. Front Microbiol 2022; 13:897682. [PMID: 35633716 PMCID: PMC9133914 DOI: 10.3389/fmicb.2022.897682] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/16/2022] [Accepted: 04/27/2022] [Indexed: 11/19/2022] Open
Abstract
Free fatty acids (FFAs) have strong antimicrobial properties against pathogenic bacteria and are known as natural protective agents against bacterial infections. Growth of the foodborne pathogen Listeria monocytogenes is highly affected by the presence of antimicrobial FFAs, however, the response of L. monocytogenes toward FFAs is not fully understood. Here, we explore how L. monocytogenes gains tolerance toward FFAs and present a novel mechanism conferring bacterial protection against FFA toxicity. Strains tolerant against the antimicrobial FFA palmitoleic acid were isolated and whole genome sequenced, and mutations were found in genes involved in wall teichoic acid (WTA) glycosylations. We show that mutation or deletion of lmo1079, which is essential for N-acetylglucosamine (GlcNAc) glycosylation of WTAs, confer tolerance against several antimicrobial FFAs. The FFA tolerant strains are lacking GlcNAc on their WTAs, which result in a more hydrophilic surface. In line with this, we observed a reduced binding of FFAs to the surface of the FFA tolerant strains. Additionally, lack of GlcNAc on WTAs confers tolerance toward acid stress. Altogether, these findings support that GlcNAc modification of WTA plays an important role in the response of L. monocytogenes toward stress conditions encountered during growth as a saprophyte and pathogen, including FFA-rich environments. Most importantly, our data revealed that L. monocytogenes strains lacking GlcNAc on their WTAs are protected against FFA toxicity, because the FFAs are repulsed from the bacterial surface of GlcNAc-deficient strains.
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Affiliation(s)
- Rikke S. S. Thomasen
- Department of Biochemistry and Molecular Biology, University of Southern Denmark, Odense, Denmark
| | - Patricia T. dos Santos
- Department of Biochemistry and Molecular Biology, University of Southern Denmark, Odense, Denmark
- National Food Institute, Technical University of Denmark, Kgs. Lyngby, Denmark
| | | | - Marianne N. Skov
- Department of Clinical Microbiology, Odense University Hospital and Research Unit of Clinical Microbiology, University of Southern Denmark, Odense, Denmark
| | - Michael Kemp
- Department of Clinical Microbiology, Odense University Hospital and Research Unit of Clinical Microbiology, University of Southern Denmark, Odense, Denmark
- The Regional Department of Clinical Microbiology, Zealand University Hospital, Koege, Denmark
| | - Birgitte H. Kallipolitis
- Department of Biochemistry and Molecular Biology, University of Southern Denmark, Odense, Denmark
- *Correspondence: Birgitte H. Kallipolitis,
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5
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Tran TT, Mathmann CD, Gatica-Andrades M, Rollo RF, Oelker M, Ljungberg JK, Nguyen TTK, Zamoshnikova A, Kummari LK, Wyer OJK, Irvine KM, Melo-Bolívar J, Gross A, Brown D, Mak JYW, Fairlie DP, Hansford KA, Cooper MA, Giri R, Schreiber V, Joseph SR, Simpson F, Barnett TC, Johansson J, Dankers W, Harris J, Wells TJ, Kapetanovic R, Sweet MJ, Latomanski EA, Newton HJ, Guérillot RJR, Hachani A, Stinear TP, Ong SY, Chandran Y, Hartland EL, Kobe B, Stow JL, Sauer-Eriksson AE, Begun J, Kling JC, Blumenthal A. Inhibition of the master regulator of Listeria monocytogenes virulence enables bacterial clearance from spacious replication vacuoles in infected macrophages. PLoS Pathog 2022; 18:e1010166. [PMID: 35007292 PMCID: PMC8746789 DOI: 10.1371/journal.ppat.1010166] [Citation(s) in RCA: 5] [Impact Index Per Article: 2.5] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/20/2021] [Accepted: 12/01/2021] [Indexed: 02/04/2023] Open
Abstract
A hallmark of Listeria (L.) monocytogenes pathogenesis is bacterial escape from maturing entry vacuoles, which is required for rapid bacterial replication in the host cell cytoplasm and cell-to-cell spread. The bacterial transcriptional activator PrfA controls expression of key virulence factors that enable exploitation of this intracellular niche. The transcriptional activity of PrfA within infected host cells is controlled by allosteric coactivation. Inhibitory occupation of the coactivator site has been shown to impair PrfA functions, but consequences of PrfA inhibition for L. monocytogenes infection and pathogenesis are unknown. Here we report the crystal structure of PrfA with a small molecule inhibitor occupying the coactivator site at 2.0 Å resolution. Using molecular imaging and infection studies in macrophages, we demonstrate that PrfA inhibition prevents the vacuolar escape of L. monocytogenes and enables extensive bacterial replication inside spacious vacuoles. In contrast to previously described spacious Listeria-containing vacuoles, which have been implicated in supporting chronic infection, PrfA inhibition facilitated progressive clearance of intracellular L. monocytogenes from spacious vacuoles through lysosomal degradation. Thus, inhibitory occupation of the PrfA coactivator site facilitates formation of a transient intravacuolar L. monocytogenes replication niche that licenses macrophages to effectively eliminate intracellular bacteria. Our findings encourage further exploration of PrfA as a potential target for antimicrobials and highlight that intra-vacuolar residence of L. monocytogenes in macrophages is not inevitably tied to bacterial persistence.
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Affiliation(s)
- Thao Thanh Tran
- The University of Queensland Diamantina Institute, Brisbane, Australia
| | | | | | - Rachel F. Rollo
- The University of Queensland Diamantina Institute, Brisbane, Australia
| | | | | | - Tam T. K. Nguyen
- The University of Queensland Diamantina Institute, Brisbane, Australia
| | | | - Lalith K. Kummari
- The University of Queensland School of Chemistry and Molecular Biosciences and Australian Infectious Diseases Research Centre, Brisbane, Australia
- Institute for Molecular Bioscience, The University of Queensland, Brisbane, Australia
| | - Orry J. K. Wyer
- The University of Queensland Diamantina Institute, Brisbane, Australia
| | - Katharine M. Irvine
- ARC Centre of Excellence in Advanced Molecular Imaging, Institute for Molecular Bioscience, The University of Queensland, Brisbane, Australia
| | | | - Annette Gross
- The University of Queensland Diamantina Institute, Brisbane, Australia
| | - Darren Brown
- Institute for Molecular Bioscience, The University of Queensland, Brisbane, Australia
| | - Jeffrey Y. W. Mak
- Institute for Molecular Bioscience, The University of Queensland, Brisbane, Australia
- ARC Centre of Excellence in Advanced Molecular Imaging, Institute for Molecular Bioscience, The University of Queensland, Brisbane, Australia
| | - David P. Fairlie
- Institute for Molecular Bioscience, The University of Queensland, Brisbane, Australia
- ARC Centre of Excellence in Advanced Molecular Imaging, Institute for Molecular Bioscience, The University of Queensland, Brisbane, Australia
| | - Karl A. Hansford
- Institute for Molecular Bioscience, The University of Queensland, Brisbane, Australia
| | - Matthew A. Cooper
- Institute for Molecular Bioscience, The University of Queensland, Brisbane, Australia
| | - Rabina Giri
- Mater Research Institute – The University of Queensland, Brisbane, Australia
| | - Veronika Schreiber
- Mater Research Institute – The University of Queensland, Brisbane, Australia
| | - Shannon R. Joseph
- The University of Queensland Diamantina Institute, Brisbane, Australia
| | - Fiona Simpson
- The University of Queensland Diamantina Institute, Brisbane, Australia
| | - Timothy C. Barnett
- Wesfarmers Centre for Vaccines and Infectious Diseases, Telethon Kids Institute, University of Western Australia, Nedlands, Australia
| | | | - Wendy Dankers
- Department of Medicine, School of Clinical Sciences at Monash Health, Faculty of Medicine, Nursing & Health Sciences, Monash University, Clayton, Australia
| | - James Harris
- Department of Medicine, School of Clinical Sciences at Monash Health, Faculty of Medicine, Nursing & Health Sciences, Monash University, Clayton, Australia
| | - Timothy J. Wells
- The University of Queensland Diamantina Institute, Brisbane, Australia
| | - Ronan Kapetanovic
- Institute for Molecular Bioscience, The University of Queensland, Brisbane, Australia
| | - Matthew J. Sweet
- Institute for Molecular Bioscience, The University of Queensland, Brisbane, Australia
| | - Eleanor A. Latomanski
- Department of Microbiology and Immunology, University of Melbourne at the Peter Doherty Institute for Infection and Immunity, Melbourne, Australia
| | - Hayley J. Newton
- Department of Microbiology and Immunology, University of Melbourne at the Peter Doherty Institute for Infection and Immunity, Melbourne, Australia
| | - Romain J. R. Guérillot
- Department of Microbiology and Immunology, University of Melbourne at the Peter Doherty Institute for Infection and Immunity, Melbourne, Australia
| | - Abderrahman Hachani
- Department of Microbiology and Immunology, University of Melbourne at the Peter Doherty Institute for Infection and Immunity, Melbourne, Australia
| | - Timothy P. Stinear
- Department of Microbiology and Immunology, University of Melbourne at the Peter Doherty Institute for Infection and Immunity, Melbourne, Australia
| | - Sze Ying Ong
- Department of Microbiology and Immunology, University of Melbourne at the Peter Doherty Institute for Infection and Immunity, Melbourne, Australia
- Centre for Innate Immunity and Infectious Diseases, Hudson Institute of Medical Research and Department of Molecular and Translational Science, Monash University, Melbourne, Australia
| | - Yogeswari Chandran
- Department of Microbiology and Immunology, University of Melbourne at the Peter Doherty Institute for Infection and Immunity, Melbourne, Australia
- Centre for Innate Immunity and Infectious Diseases, Hudson Institute of Medical Research and Department of Molecular and Translational Science, Monash University, Melbourne, Australia
| | - Elizabeth L. Hartland
- Department of Microbiology and Immunology, University of Melbourne at the Peter Doherty Institute for Infection and Immunity, Melbourne, Australia
- Centre for Innate Immunity and Infectious Diseases, Hudson Institute of Medical Research and Department of Molecular and Translational Science, Monash University, Melbourne, Australia
| | - Bostjan Kobe
- The University of Queensland School of Chemistry and Molecular Biosciences and Australian Infectious Diseases Research Centre, Brisbane, Australia
- Institute for Molecular Bioscience, The University of Queensland, Brisbane, Australia
| | - Jennifer L. Stow
- Institute for Molecular Bioscience, The University of Queensland, Brisbane, Australia
| | | | - Jakob Begun
- Mater Research Institute – The University of Queensland, Brisbane, Australia
| | - Jessica C. Kling
- The University of Queensland Diamantina Institute, Brisbane, Australia
| | - Antje Blumenthal
- The University of Queensland Diamantina Institute, Brisbane, Australia
- * E-mail:
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6
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DeMars ZR, Krute CN, Ridder MJ, Gilchrist AK, Menjivar C, Bose JL. Fatty acids can inhibit Staphylococcus aureus SaeS activity at the membrane independent of alterations in respiration. Mol Microbiol 2021; 116:1378-1391. [PMID: 34626146 DOI: 10.1111/mmi.14830] [Citation(s) in RCA: 2] [Impact Index Per Article: 0.7] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/13/2021] [Revised: 10/06/2021] [Accepted: 10/06/2021] [Indexed: 12/29/2022]
Abstract
In Staphylococcus aureus, the two-component system SaeRS is responsible for regulating various virulence factors essential for the success of this pathogen. SaeRS can be stimulated by neutrophil-derived products but has also recently been shown to be inactivated by the presence of free fatty acids. A mechanism for how fatty acids negatively impacts SaeRS has not been described. We found that unsaturated fatty acids, as well as fatty acids not commonly found in Staphylococcal membranes, prevent the activation of SaeRS at a lower concentration than their saturated counterparts. These fatty acids can negatively impact SaeRS without altering the respiratory capacity of the bacterium. To uncover a potential mechanism for how fatty acids impact SaeRS function/activity, we utilized a naturally occurring point mutation found in S. aureus as well as chimeric SaeS proteins. Using these tools, we identified that the native transmembrane domains of SaeS dictate the transcriptional response to fatty acids in S. aureus. Our data support a model where free fatty acids alter the activity of the two-component system SaeRS directly through the sensor kinase SaeS and is dependent on the transmembrane domains of the protein.
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Affiliation(s)
- Zachary R DeMars
- Department of Microbiology, Molecular Genetics and Immunology, University of Kansas Medical Center, Kansas City, Kansas, USA
| | - Christina N Krute
- Department of Microbiology, Molecular Genetics and Immunology, University of Kansas Medical Center, Kansas City, Kansas, USA
| | - Miranda J Ridder
- Department of Microbiology, Molecular Genetics and Immunology, University of Kansas Medical Center, Kansas City, Kansas, USA
| | - Aubrey K Gilchrist
- Department of Microbiology, Molecular Genetics and Immunology, University of Kansas Medical Center, Kansas City, Kansas, USA
| | - Cindy Menjivar
- Department of Microbiology, Molecular Genetics and Immunology, University of Kansas Medical Center, Kansas City, Kansas, USA
| | - Jeffrey L Bose
- Department of Microbiology, Molecular Genetics and Immunology, University of Kansas Medical Center, Kansas City, Kansas, USA
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7
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Villoria Recio M, Lee BH, Lillebæk EMS, Kallipolitis BH, Gahan CGM, Ingmer H, Larsen MH. Chitin Attenuates Expression of Listeria monocytogenes Virulence Genes in vitro. Front Microbiol 2020; 11:588906. [PMID: 33343529 PMCID: PMC7744463 DOI: 10.3389/fmicb.2020.588906] [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: 07/29/2020] [Accepted: 11/12/2020] [Indexed: 11/13/2022] Open
Abstract
External signals are crucial for bacteria to sense their immediate environment and fine-tune gene expression accordingly. The foodborne pathogen Listeria monocytogenes senses a range of environmental cues in order to activate or deactivate the virulence-inducing transcriptional factor PrfA during transition between infectious and saprophytic lifecycles. Chitin is an abundant biopolymer formed from linked β-(1-4)-N-acetyl-D-glucosamine residues associated with fungi, the exoskeleton of insects and often incorporated into foods as a thickener or stabilizer. L. monocytogenes evolved to hydrolyse chitin, presumably, to facilitate nutrient acquisition from competitive environments such as soil where the polymer is abundant. Since mammals do not produce chitin, we reasoned that the polymer could serve as an environmental signal contributing to repression of L. monocytogenes PrfA-dependent expression. This study shows a significant downregulation of the core PrfA-regulon during virulence-inducing conditions in vitro in the presence of chitin. Our data suggest this phenomenon occurs through a mechanism that differs from PTS-transport of oligosaccharides generated from either degradation or chitinase-mediated hydrolysis of the polymer. Importantly, an indication that chitin can repress virulence expression of a constitutively active PrfA∗ mutant is shown, possibly mediated via a post-translational modification inhibiting PrfA∗ activity. To our knowledge, this is the first time that chitin is reported as a molecule with anti-virulence properties against a pathogenic bacterium. Thus, our findings identify chitin as a signal which may downregulate the virulence potential of the pathogen and may provide an alternative approach toward reducing disease risk.
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Affiliation(s)
- Miguel Villoria Recio
- Department of Veterinary and Animal Sciences, Faculty of Health and Medical Sciences, Food Safety and Zoonoses-University of Copenhagen, Frederiksberg, Denmark.,Alimentary Pharmabotic Centre Microbiome Ireland, University College Cork, Cork, Ireland.,School of Microbiology, University College Cork, Cork, Ireland
| | - Bo-Hyung Lee
- Université Paris-Saclay, INRAE, UVSQ, VIM, Jouy-en-Josas, France
| | | | - Birgitte H Kallipolitis
- Department of Biochemistry and Molecular Biology, University of Southern Denmark, Odense, Denmark
| | - Cormac G M Gahan
- Alimentary Pharmabotic Centre Microbiome Ireland, University College Cork, Cork, Ireland.,School of Microbiology, University College Cork, Cork, Ireland
| | - Hanne Ingmer
- Department of Veterinary and Animal Sciences, Faculty of Health and Medical Sciences, Food Safety and Zoonoses-University of Copenhagen, Frederiksberg, Denmark
| | - Marianne Halberg Larsen
- Department of Veterinary and Animal Sciences, Faculty of Health and Medical Sciences, Food Safety and Zoonoses-University of Copenhagen, Frederiksberg, Denmark
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