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Cao X, van Putten JP, Wösten MM. Campylobacter jejuni benefits from the bile salt deoxycholate under low-oxygen condition in a PldA dependent manner. Gut Microbes 2023; 15:2262592. [PMID: 37768138 PMCID: PMC10540661 DOI: 10.1080/19490976.2023.2262592] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 04/07/2023] [Accepted: 09/20/2023] [Indexed: 09/29/2023] Open
Abstract
Enteric bacteria need to adapt to endure the antibacterial activities of bile salts in the gut. Phospholipase A (PldA) is a key enzyme in the maintenance of bacterial membrane homeostasis. Bacteria respond to stress by modulating their membrane composition. Campylobacter jejuni is the most common cause of human worldwide. However, the mechanism by which C. jejuni adapts and survives in the gut environment is not fully understood. In this study, we investigated the roles of PldA, bile salt sodium deoxycholate (DOC), and oxygen availability in C. jejuni biology, mimicking an in vivo situation. Growth curves were used to determine the adaptation of C. jejuni to bile salts. RNA-seq and functional assays were employed to investigate the PldA-dependent and DOC-induced changes in gene expression that influence bacterial physiology. Survival studies were performed to address oxidative stress defense in C. jejuni. Here, we discovered that PldA of C. jejuni is required for optimal growth in the presence of bile salt DOC. Under high oxygen conditions, DOC is toxic to C. jejuni, but under low oxygen conditions, as is present in the lumen of the gut, C. jejuni benefits from DOC. C. jejuni PldA seems to enable the use of iron needed for optimal growth in the presence of DOC but makes the bacterium more vulnerable to oxidative stress. In conclusion, DOC stimulates C. jejuni growth under low oxygen conditions and alters colony morphology in a PldA-dependent manner. C. jejuni benefits from DOC by upregulating iron metabolism in a PldA-dependent manner.
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Affiliation(s)
- Xuefeng Cao
- Department Biomolecular Health Sciences, Utrecht University, Utrecht, The Netherlands
| | - Jos P.M. van Putten
- Department Biomolecular Health Sciences, Utrecht University, Utrecht, The Netherlands
| | - Marc M.S.M. Wösten
- Department Biomolecular Health Sciences, Utrecht University, Utrecht, The Netherlands
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2
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Influence of Hurdle Technology on Foodborne Pathogen Survival in the Human Gastrointestinal Tract. Microorganisms 2023; 11:microorganisms11020405. [PMID: 36838370 PMCID: PMC9960521 DOI: 10.3390/microorganisms11020405] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/09/2023] [Revised: 01/30/2023] [Accepted: 02/01/2023] [Indexed: 02/08/2023] Open
Abstract
The application of several sublethal stresses in hurdle technology can exert microbial stress resistance, which, in turn, might enable foodborne pathogens to overcome other types of lethal stresses, such as the gastrointestinal barriers. The present study evaluated the survival of Salmonella Typhimurium and Listeria monocytogenes during simulated digestion, following exposure to combinations of water activity (aw), pH and storage temperature stresses. The results revealed that both pathogens survived their passage through the simulated gastrointestinal tract (GIT) with their previous habituation to certain hurdle combinations inducing stress tolerance. More specifically, the habituation to a low temperature or to a high pH resulted in the increased stress tolerance of Salmonella, while for Listeria, the cells appeared stress tolerant after exposure to a high temperature or to a low pH. Nonetheless, both pathogens expressed increased sensitivity after habituation to growth-limiting hurdle combinations. The survival of stress-tolerant pathogenic cells in the human GIT poses major public health issues, since it can lead to host infection. Consequently, further research is required to obtain a deeper understanding of the adaptive stress responses of foodborne bacteria after exposure to combinations of sublethal hurdles to improve the existing food safety systems.
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3
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Effect of gastric pH and bile acids on the survival of Listeria monocytogenes and Salmonella Typhimurium during simulated gastrointestinal digestion. INNOV FOOD SCI EMERG 2022. [DOI: 10.1016/j.ifset.2022.103161] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/05/2022]
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4
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Chakravarty D, Sahukhal G, Arick M, Davis ML, Donaldson JR. Transcriptomic Analysis of Listeria monocytogenes in Response to Bile Under Aerobic and Anaerobic Conditions. Front Microbiol 2021; 12:754748. [PMID: 34867878 PMCID: PMC8636025 DOI: 10.3389/fmicb.2021.754748] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/06/2021] [Accepted: 10/18/2021] [Indexed: 11/13/2022] Open
Abstract
Listeria monocytogenes is a gram-positive facultative anaerobic bacterium that causes the foodborne illness listeriosis. The pathogenesis of this bacterium depends on its survival in anaerobic, acidic, and bile conditions encountered throughout the gastrointestinal (GI) tract. This transcriptomics study was conducted to analyze the differences in transcript levels produced under conditions mimicking the GI tract. Changes in transcript levels were analyzed using RNA isolated from L. monocytogenes strain F2365 at both aerobic and anaerobic conditions, upon exposure to 0 and 1% bile at acidic and neutral pH. Transcripts corresponding to genes responsible for pathogenesis, cell wall associated proteins, DNA repair, transcription factors, and stress responses had variations in levels under the conditions tested. Upon exposure to anaerobiosis in acidic conditions, there were variations in the transcript levels for the virulence factors internalins, listeriolysin O, etc., as well as many histidine sensory kinases. These data indicate that the response to anaerobiosis differentially influences the transcription of several genes related to the survival of L. monocytogenes under acidic and bile conditions. Though further research is needed to decipher the role of oxygen in pathogenesis of L. monocytogenes, these data provide comprehensive information on how this pathogen responds to the GI tract.
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Affiliation(s)
- Damayanti Chakravarty
- Cell and Molecular Biology, The University of Southern Mississippi, Hattiesburg, MS, United States
| | - Gyan Sahukhal
- Cell and Molecular Biology, The University of Southern Mississippi, Hattiesburg, MS, United States
| | - Mark Arick
- Institute for Genomics, Biocomputing & Biotechnology, Mississippi State University, Mississippi State, MS, United States
| | - Morgan L. Davis
- Department of Biological Sciences, Mississippi State University, Mississippi State, MS, United States
| | - Janet R. Donaldson
- Cell and Molecular Biology, The University of Southern Mississippi, Hattiesburg, MS, United States
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5
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Boonmee A, Oliver HF, Chaturongakul S. Listeria monocytogenes 10403S Alternative Sigma-54 Factor σ L Has a Negative Role on Survival Ability Under Bile Exposure. Front Microbiol 2021; 12:713383. [PMID: 34745026 PMCID: PMC8568364 DOI: 10.3389/fmicb.2021.713383] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/22/2021] [Accepted: 09/24/2021] [Indexed: 12/24/2022] Open
Abstract
Listeria monocytogenes is a Gram-positive bacterium causing listeriosis in animals and humans. To initiate a foodborne infection, L. monocytogenes has to pass through the host gastrointestinal tract (GIT). In this study, we evaluated survival abilities of L. monocytogenes 10403S wild type (WT) and its isogenic mutants in alternative sigma (σ) factor genes (i.e., sigB, sigC, sigH, and sigL) under simulated gastric, duodenal, and bile fluids. Within 10min of exposures, only bile fluid was able to significantly reduce survival ability of L. monocytogenes WT by 2 logs CFU/ml. Loss of sigL showed the greatest bile resistance among 16 strains tested, p<0.0001, (i.e., WT, four single alternative σ factor mutants, six double mutants, four triple mutants, and one quadruple mutant). To further investigate the role of σL in bile response, RNA-seq was conducted to compare the transcriptional profiles among L. monocytogenes 10403S ΔBCH triple mutant (lacking sigB, sigC, and sigH genes; expressing housekeeping σA and σL) and ΔBCHL quadruple mutant (lacking all alternative sigma factor genes; expressing only σA) strains under BHI and 1% bile conditions. A total of 216 and 176 differentially expressed genes (DEGs) were identified in BHI and bile, respectively. We confirmed that mpt operon was shown to be strongly activated by σL. Interestingly, more than 80% of DEGs were found to be negatively regulated in the presence of σL. This includes PrfA regulon and its mediated genes (i.e., hly, hpt, inlB, clpP, clpE, groL, and inlC) which were downregulated in response to bile in the presence of σL. This result suggests the potential negative role of σL on bile survival, and the roles of σL and σB might be in a seesaw model prior to host cell invasion.
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Affiliation(s)
- Atsadang Boonmee
- Department of Microbiology, Faculty of Science, Chulalongkorn University, Bangkok, Thailand
| | - Haley F Oliver
- Department of Food Science, College of Agriculture, Purdue University, West Lafayette, IN, United States
| | - Soraya Chaturongakul
- Department of Microbiology, Faculty of Science, Mahidol University, Bangkok, Thailand.,Systems Biology of Diseases Research Unit, Faculty of Science, Mahidol University, Bangkok, Thailand
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6
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Gkerekou MA, Athanaseli KG, Kapetanakou AE, Drosinos EH, Skandamis PN. Εvaluation of oxygen availability on growth and inter-strain interactions of L. monocytogenes in/on liquid, semi-solid and solid laboratory media. Int J Food Microbiol 2021; 341:109052. [PMID: 33515814 DOI: 10.1016/j.ijfoodmicro.2021.109052] [Citation(s) in RCA: 4] [Impact Index Per Article: 1.3] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/16/2020] [Revised: 12/30/2020] [Accepted: 12/31/2020] [Indexed: 12/20/2022]
Abstract
The coexistence and interactions among Listeria monocytogenes strains in combination with the structural characteristics of foods, may influence their growth capacity and thus, the final levels at the time of consumption. In the present study, we aimed to evaluate the effect of oxygen availability in combination with substrate micro-structure on growth and inter-strain interactions of L. monocytogenes. L. monocytogenes strains, selected for resistance to different antibiotics (to enable distinct enumeration), belonging to serotypes 4b (C5, ScottA), 1/2a (6179) and 1/2b (PL25) and were inoculated in liquid (Tryptic Soy Broth supplemented with Yeast Extract - TSB-YE) and solid (TSB-YE supplemented with 0.6% and 1.2% agar) media (2-3 log CFU/mL, g or cm2), single or as two-strain cultures (1:1 strain-ratio). Aerobic conditions (A) were achieved with constant shaking or surface inoculation for liquid and solid media respectively, while static incubation or pour plated media corresponded to hypoxic environment (H). Anoxic conditions (An) were attained by adding 0.1% w/v sodium thioglycolate and paraffin overlay (for solid media). Growth was assessed during storage at 7 °C (n = 3 × 2). Inter-strain interactions were manifested by the difference in the final population between singly and co-cultured strains. Τhe extent of suppression increased with reduction in agar concentration, while the impact of oxygen availability was dependent on strain combination. During co-culture, in liquid and solid media, 6179 was suppressed by C5 by 4.0 (in TSB-YE under H) to 1.8 log units (in solid medium under An), compared to the single culture, which attained population of ca. 9.4 log CFU/mL or g. The growth of 6179 was also inhibited by ScottA by 2.7 and 1.9 log units, in liquid culture under H and An, respectively. Interestingly, in liquid medium under A, H and An, ScottA was suppressed by C5, by 3.3, 2.4 and 2.3 log units, respectively, while in solid media, growth inhibition was less pronounced. Investigating growth interactions in different environments could assist in explaining the dominance of L. monocytogenes certain serotypes.
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Affiliation(s)
- Maria A Gkerekou
- Laboratory of Food Quality Control and Hygiene, Department of Food Science and Human Nutrition, Agricultural University of Athens, Greece
| | - Konstantina G Athanaseli
- Laboratory of Food Quality Control and Hygiene, Department of Food Science and Human Nutrition, Agricultural University of Athens, Greece
| | - Anastasia E Kapetanakou
- Laboratory of Food Quality Control and Hygiene, Department of Food Science and Human Nutrition, Agricultural University of Athens, Greece
| | - Eleftherios H Drosinos
- Laboratory of Food Quality Control and Hygiene, Department of Food Science and Human Nutrition, Agricultural University of Athens, Greece
| | - Panagiotis N Skandamis
- Laboratory of Food Quality Control and Hygiene, Department of Food Science and Human Nutrition, Agricultural University of Athens, Greece.
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7
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Arcari T, Feger ML, Guerreiro DN, Wu J, O’Byrne CP. Comparative Review of the Responses of Listeria monocytogenes and Escherichia coli to Low pH Stress. Genes (Basel) 2020; 11:genes11111330. [PMID: 33187233 PMCID: PMC7698193 DOI: 10.3390/genes11111330] [Citation(s) in RCA: 42] [Impact Index Per Article: 10.5] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/30/2020] [Revised: 11/03/2020] [Accepted: 11/09/2020] [Indexed: 02/07/2023] Open
Abstract
Acidity is one of the principal physicochemical factors that influence the behavior of microorganisms in any environment, and their response to it often determines their ability to grow and survive. Preventing the growth and survival of pathogenic bacteria or, conversely, promoting the growth of bacteria that are useful (in biotechnology and food production, for example), might be improved considerably by a deeper understanding of the protective responses that these microorganisms deploy in the face of acid stress. In this review, we survey the molecular mechanisms used by two unrelated bacterial species in their response to low pH stress. We chose to focus on two well-studied bacteria, Escherichia coli (phylum Proteobacteria) and Listeria monocytogenes (phylum Firmicutes), that have both evolved to be able to survive in the mammalian gastrointestinal tract. We review the mechanisms that these species use to maintain a functional intracellular pH as well as the protective mechanisms that they deploy to prevent acid damage to macromolecules in the cells. We discuss the mechanisms used to sense acid in the environment and the regulatory processes that are activated when acid is encountered. We also highlight the specific challenges presented by organic acids. Common themes emerge from this comparison as well as unique strategies that each species uses to cope with acid stress. We highlight some of the important research questions that still need to be addressed in this fascinating field.
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8
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Roberts BN, Chakravarty D, Gardner J, Ricke SC, Donaldson JR. Listeria monocytogenes Response to Anaerobic Environments. Pathogens 2020; 9:pathogens9030210. [PMID: 32178387 PMCID: PMC7157565 DOI: 10.3390/pathogens9030210] [Citation(s) in RCA: 20] [Impact Index Per Article: 5.0] [Reference Citation Analysis] [Abstract] [Key Words] [Grants] [Track Full Text] [Download PDF] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/24/2020] [Revised: 03/09/2020] [Accepted: 03/10/2020] [Indexed: 12/19/2022] Open
Abstract
Listeria monocytogenes is a Gram-positive facultative anaerobic bacterium that is responsible for the disease, listeriosis. It is particularly lethal in pregnant women, the fetus, the elderly and the immunocompromised. The pathogen survives and replicates over a wide range of temperatures (4 to 42 °C), pH, salt and oxygen concentrations. Because it can withstand various environments, L. monocytogenes is a major concern in food processing industries, especially in dairy products and ready-to-eat fruits, vegetables and deli meats. The environment in which the pathogen is exposed can influence the expression of virulence genes. For instance, studies have shown that variations in oxygen availability can impact resistance to stressors. Further investigation is needed to understand the essential genes required for the growth of L. monocytogenes in anaerobic conditions. Therefore, the purpose of this review is to highlight the data on L. monocytogenes under known environmental stresses in anaerobic environments and to focus on gaps in knowledge that may be advantageous to study in order to better understand the pathogenicity of the bacterium.
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Affiliation(s)
- Brandy N. Roberts
- Department of Biological Sciences, Mississippi State University, Mississippi State, MS 39762, USA;
| | - Damayanti Chakravarty
- Cell and Molecular Biology, The University of Southern Mississippi, Hattiesburg, MS 39406, USA; (D.C.); (J.C.G.III)
| | - J.C. Gardner
- Cell and Molecular Biology, The University of Southern Mississippi, Hattiesburg, MS 39406, USA; (D.C.); (J.C.G.III)
| | - Steven C. Ricke
- Center for Food Safety, Department of Food Science, University of Arkansas, Fayetteville, AR 72704, USA;
| | - Janet R. Donaldson
- Cell and Molecular Biology, The University of Southern Mississippi, Hattiesburg, MS 39406, USA; (D.C.); (J.C.G.III)
- Correspondence: ; Tel.: +1-601-206-6795
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9
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Shah MK, Bergholz TM. Variation in growth and evaluation of cross-protection in Listeria monocytogenes under salt and bile stress. J Appl Microbiol 2020; 129:367-377. [PMID: 32027767 DOI: 10.1111/jam.14607] [Citation(s) in RCA: 6] [Impact Index Per Article: 1.5] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/28/2019] [Revised: 12/09/2019] [Accepted: 02/04/2020] [Indexed: 12/13/2022]
Abstract
AIMS Exposure of Listeria monocytogenes to osmotic stress can induce increased resistance to subsequent lethal exposure to cell envelope stressors, such as nisin and bile salts. We wanted to determine if similar cross-protection phenotypes could occur when L. monocytogenes strains were treated with osmotic stress and exposed to sublethal levels of the cell envelope stressor, bile. METHOD AND RESULTS Growth phenotypes were measured for six L. monocytogenes strains exposed to 6% NaCl, 0·3 and 1% bile in BHI. To evaluate cross-protection, cells were pre-exposed to 6% NaCl, followed by exposure to BHI+1% bile for 26 h and vice versa. Significant increases in λ (lag phase) and doubling time were observed under salt and bile stresses compared with BHI alone. Average λ and Nmax (maximum cell density) in 0·3 and 1% bile for all strains were significantly lower than that in 6% NaCl. Pre-exposure to 6% NaCl followed by exposure to 1% bile significantly increased λ (P < 0·05), whereas pre-exposure to 1% bile followed by exposure to 6% NaCl led to formation of filamentous cells, with no changes in cell density over 26 h. CONCLUSIONS Variation in growth characteristics was observed among strains exposed to bile. Exposure to osmotic stress did not lead to increased resistance to bile. Exposure to bile significantly impacted the ability of L. monocytogenes to adapt to grow under osmotic stress, where cells did not multiply but formed filamentous cells. SIGNIFICANCE AND IMPACT OF THE STUDY Pre-exposure to a cell envelope stress and subsequent exposure to an osmotic stress appears to pose a significant stress to L. monocytogenes cells.
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Affiliation(s)
- M K Shah
- Department of Microbiological Sciences, North Dakota State University, Fargo, ND, USA
| | - T M Bergholz
- Department of Microbiological Sciences, North Dakota State University, Fargo, ND, USA
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10
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Boonmee A, Oliver HF, Chaturongakul S. Listeria monocytogenes σ A Is Sufficient to Survive Gallbladder Bile Exposure. Front Microbiol 2019; 10:2070. [PMID: 31551995 PMCID: PMC6737072 DOI: 10.3389/fmicb.2019.02070] [Citation(s) in RCA: 5] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/07/2019] [Accepted: 08/22/2019] [Indexed: 12/17/2022] Open
Abstract
Listeria monocytogenes is a foodborne Gram-positive bacterium causing listeriosis in both animals and humans. It can persist and grow in various environments including conditions countered during saprophytic or intra-host lifestyles. Sigma (σ) subunit of RNA polymerase is a transcriptional factor responsible for guiding the core RNA polymerase and initiating gene expression under normal growth or physiological changes. In L. monocytogenes, there is one housekeeping sigma factor, σA, and four alternative sigma factors σB, σC, σH, and σL. Generally, σA directs expression of genes required for normal growth while alternative σ factors alter gene expression in response to specific conditions (e.g., stress). In this study, we aimed to determine the exclusive role of σA in L. monocytogenes by comparing a wild type strain with its isogenic mutant lacking genes encoding all alternative sigma factors (i.e., sigB, sigC, sigH, and sigL). We further investigated their survival abilities in 6% porcine bile (pH 8.2) mimicking gallbladder bile and their transcriptomics profiles in rich medium (i.e., BHI) and 1% porcine bile. Surprisingly, the results showed that survival abilities of wild type and ΔsigBΔsigCΔsigHΔsigL (or ΔsigBCHL) quadruple mutant strains in 6% bile were similar suggesting a compensatory role for σA. RNA-seq results revealed that bile stimulon of L. monocytogenes wild type contained 66 genes (43 and 23 genes were up- and down-regulated, respectively); however, only 29 genes (five up- and 24 down-regulated by bile) were differentially expressed in ΔsigBCHL. We have shown that bile exposure mediates increased transcription levels of dlt and ilv operons and decreased transcription levels of prfA and heat shock genes in wild type. Furthermore, we identified σA-dependent bile inducible genes that are involved in phosphotransferase systems, chaperones, and transporter systems; these genes appear to contribute to L. monocytogenes cellular homeostasis. As a result, σA seemingly plays a compensatory role in the absence of alternative sigma factors under bile exposure. Our data support that the bile stimulon is prone to facilitate resistance to bile prior to initiated infection.
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Affiliation(s)
- Atsadang Boonmee
- Department of Microbiology, Faculty of Science, Mahidol University, Bangkok, Thailand
| | - Haley F. Oliver
- Department of Food Science, College of Agriculture, Purdue University, West Lafayette, IN, United States
| | - Soraya Chaturongakul
- Department of Microbiology, Faculty of Science, Mahidol University, Bangkok, Thailand
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11
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Ducarmon QR, Zwittink RD, Hornung BVH, van Schaik W, Young VB, Kuijper EJ. Gut Microbiota and Colonization Resistance against Bacterial Enteric Infection. Microbiol Mol Biol Rev 2019; 83:e00007-19. [PMID: 31167904 PMCID: PMC6710460 DOI: 10.1128/mmbr.00007-19] [Citation(s) in RCA: 275] [Impact Index Per Article: 55.0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 02/06/2023] Open
Abstract
The gut microbiome is critical in providing resistance against colonization by exogenous microorganisms. The mechanisms via which the gut microbiota provide colonization resistance (CR) have not been fully elucidated, but they include secretion of antimicrobial products, nutrient competition, support of gut barrier integrity, and bacteriophage deployment. However, bacterial enteric infections are an important cause of disease globally, indicating that microbiota-mediated CR can be disturbed and become ineffective. Changes in microbiota composition, and potential subsequent disruption of CR, can be caused by various drugs, such as antibiotics, proton pump inhibitors, antidiabetics, and antipsychotics, thereby providing opportunities for exogenous pathogens to colonize the gut and ultimately cause infection. In addition, the most prevalent bacterial enteropathogens, including Clostridioides difficile, Salmonella enterica serovar Typhimurium, enterohemorrhagic Escherichia coli, Shigella flexneri, Campylobacter jejuni, Vibrio cholerae, Yersinia enterocolitica, and Listeria monocytogenes, can employ a wide array of mechanisms to overcome colonization resistance. This review aims to summarize current knowledge on how the gut microbiota can mediate colonization resistance against bacterial enteric infection and on how bacterial enteropathogens can overcome this resistance.
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Affiliation(s)
- Q R Ducarmon
- Center for Microbiome Analyses and Therapeutics, Leiden University Medical Center, Leiden, Netherlands
- Experimental Bacteriology, Department of Medical Microbiology, Leiden University Medical Center, Leiden, Netherlands
| | - R D Zwittink
- Center for Microbiome Analyses and Therapeutics, Leiden University Medical Center, Leiden, Netherlands
- Experimental Bacteriology, Department of Medical Microbiology, Leiden University Medical Center, Leiden, Netherlands
| | - B V H Hornung
- Center for Microbiome Analyses and Therapeutics, Leiden University Medical Center, Leiden, Netherlands
- Experimental Bacteriology, Department of Medical Microbiology, Leiden University Medical Center, Leiden, Netherlands
| | - W van Schaik
- Institute of Microbiology and Infection, University of Birmingham, Birmingham, United Kingdom
| | - V B Young
- Department of Microbiology and Immunology, University of Michigan, Ann Arbor, Michigan, USA
- Department of Internal Medicine/Infectious Diseases Division, University of Michigan Medical Center, Ann Arbor, Michigan, USA
| | - E J Kuijper
- Center for Microbiome Analyses and Therapeutics, Leiden University Medical Center, Leiden, Netherlands
- Experimental Bacteriology, Department of Medical Microbiology, Leiden University Medical Center, Leiden, Netherlands
- Clinical Microbiology Laboratory, Department of Medical Microbiology, Leiden University Medical Center, Leiden, Netherlands
- Netherlands Donor Feces Bank, Leiden, Netherlands
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12
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Harris J, Paul O, Park SH, White SJ, Budachetri K, McClung DM, Wilson JG, Olivier AK, Thornton JA, Broadway PR, Ricke SC, Donaldson JR. Oxygen deprivation influences the survival of Listeria monocytogenes in gerbils. Transl Anim Sci 2018; 3:102-112. [PMID: 30627705 PMCID: PMC6310367 DOI: 10.1093/tas/txy110] [Citation(s) in RCA: 3] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/10/2018] [Accepted: 10/03/2018] [Indexed: 11/27/2022] Open
Abstract
Listeria monocytogenes is a facultative anaerobic foodborne pathogen capable of surviving harsh environments. Recent work has indicated that anaerobic conditions increase the resistance capability of certain strains to environmental stressors. The goal of the study was to conduct a preliminary study to determine whether exposure to anaerobic conditions prior to infection increases the ability to survive in vivo. Gerbils were inoculated with one of five doses of the L. monocytogenes strain F2365 by oral gavage: phosphate-buffered saline (control), 5 × 106 colony forming units aerobic culture (low aerobic), 5 × 108 aerobic culture (high aerobic), 5 × 106 anaerobic culture (low anaerobic), or 5 × 108 anaerobic culture (high anaerobic) dose of F2365. Gerbils inoculated with a high aerobic or anaerobic dose exhibited significant weight loss. Gerbils administered either the low or high anaerobic dose had at least 3 log10 of L. monocytogenes present in fecal samples, which contrasted with gerbils that received the low aerobic dose. Animals that received the high anaerobic dose had a significant increase in bacterial loads within the liver. Histologic examination of the L. monocytogenes positive livers exhibited locally extensive areas of hepatocellular necrosis, though the extent of this damage differed between treatment groups. Microbial community analysis of the cecum from gerbils infected with L. monocytogenes indicated that the abundance of Bacteroidales and Clostridiales increased and there was a decrease in the abundance of Spirochaetales. This study suggests that anaerobic conditions alter the localization pattern of L. monocytogenes within the gastrointestinal tract. These findings could relate to how different populations are more susceptible to listeriosis, as oxygen availability may differ within the gastrointestinal tract.
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Affiliation(s)
- Jillian Harris
- Department of Biological Sciences, Mississippi State University, Mississippi State, MS
| | - Oindrila Paul
- Department of Biological Sciences, The University of Southern Mississippi, Hattiesburg, MS
| | - Si Hong Park
- Department of Food Science and Center for Food Safety, University of Arkansas, Fayetteville, AR
| | - Sally J White
- Department of Biological Sciences, The University of Southern Mississippi, Hattiesburg, MS
| | - Khemraj Budachetri
- Department of Biological Sciences, The University of Southern Mississippi, Hattiesburg, MS
| | - Daniel M McClung
- Department of Biological Sciences, Mississippi State University, Mississippi State, MS
| | - Jessica G Wilson
- Burnett School of Biomedical Sciences, University of Central Florida, Orlando, FL
| | - Alicia K Olivier
- Department of Pathobiology and Population Medicine, College of Veterinary Medicine, Mississippi State University, Mississippi State, MS
| | - Justin A Thornton
- Department of Biological Sciences, Mississippi State University, Mississippi State, MS
| | | | - Steven C Ricke
- Department of Food Science and Center for Food Safety, University of Arkansas, Fayetteville, AR
| | - Janet R Donaldson
- Department of Biological Sciences, The University of Southern Mississippi, Hattiesburg, MS
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13
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Guariglia-Oropeza V, Orsi RH, Guldimann C, Wiedmann M, Boor KJ. The Listeria monocytogenes Bile Stimulon under Acidic Conditions Is Characterized by Strain-Specific Patterns and the Upregulation of Motility, Cell Wall Modification Functions, and the PrfA Regulon. Front Microbiol 2018; 9:120. [PMID: 29467736 PMCID: PMC5808219 DOI: 10.3389/fmicb.2018.00120] [Citation(s) in RCA: 17] [Impact Index Per Article: 2.8] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/19/2017] [Accepted: 01/18/2018] [Indexed: 11/16/2022] Open
Abstract
Listeria monocytogenes uses a variety of transcriptional regulation strategies to adapt to the extra-host environment, the gastrointestinal tract, and the intracellular host environment. While the alternative sigma factor SigB has been proposed to be a key transcriptional regulator that facilitates L. monocytogenes adaptation to the gastrointestinal environment, the L. monocytogenes' transcriptional response to bile exposure is not well-understood. RNA-seq characterization of the bile stimulon was performed in two L. monocytogenes strains representing lineages I and II. Exposure to bile at pH 5.5 elicited a large transcriptomic response with ~16 and 23% of genes showing differential transcription in 10403S and H7858, respectively. The bile stimulon includes genes involved in motility and cell wall modification mechanisms, as well as genes in the PrfA regulon, which likely facilitate survival during the gastrointestinal stages of infection that follow bile exposure. The fact that bile exposure induced the PrfA regulon, but did not induce further upregulation of the SigB regulon (beyond that expected by exposure to pH 5.5), suggests a model where at the earlier stages of gastrointestinal infection (e.g., acid exposure in the stomach), SigB-dependent gene expression plays an important role. Subsequent exposure to bile induces the PrfA regulon, potentially priming L. monocytogenes for subsequent intracellular infection stages. Some members of the bile stimulon showed lineage- or strain-specific distribution when 27 Listeria genomes were analyzed. Even though sigB null mutants showed increased sensitivity to bile, the SigB regulon was not found to be upregulated in response to bile beyond levels expected by exposure to pH 5.5. Comparison of wildtype and corresponding ΔsigB strains newly identified 26 SigB-dependent genes, all with upstream putative SigB-dependent promoters.
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Affiliation(s)
| | - Renato H Orsi
- Food Safety Laboratory, Department of Food Science, Cornell University, Ithaca, NY, United States
| | - Claudia Guldimann
- Food Safety Laboratory, Department of Food Science, Cornell University, Ithaca, NY, United States
| | - Martin Wiedmann
- Food Safety Laboratory, Department of Food Science, Cornell University, Ithaca, NY, United States
| | - Kathryn J Boor
- Food Safety Laboratory, Department of Food Science, Cornell University, Ithaca, NY, United States
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Abstract
This narrative review summarises the benefits, risks and appropriate use of acid-suppressing drugs (ASDs), proton pump inhibitors and histamine-2 receptor antagonists, advocating a rationale balanced and individualised approach aimed to minimise any serious adverse consequences. It focuses on current controversies on the potential of ASDs to contribute to infections-bacterial, parasitic, fungal, protozoan and viral, particularly in the elderly, comprehensively and critically discusses the growing body of observational literature linking ASD use to a variety of enteric, respiratory, skin and systemic infectious diseases and complications (Clostridium difficile diarrhoea, pneumonia, spontaneous bacterial peritonitis, septicaemia and other). The proposed pathogenic mechanisms of ASD-associated infections (related and unrelated to the inhibition of gastric acid secretion, alterations of the gut microbiome and immunity), and drug-drug interactions are also described. Both probiotics use and correcting vitamin D status may have a significant protective effect decreasing the incidence of ASD-associated infections, especially in the elderly. Despite the limitations of the existing data, the importance of individualised therapy and caution in long-term ASD use considering the balance of benefits and potential harms, factors that may predispose to and actions that may prevent/attenuate adverse effects is evident. A six-step practical algorithm for ASD therapy based on the best available evidence is presented.
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15
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Survival of the Fittest: How Bacterial Pathogens Utilize Bile To Enhance Infection. Clin Microbiol Rev 2017; 29:819-36. [PMID: 27464994 DOI: 10.1128/cmr.00031-16] [Citation(s) in RCA: 68] [Impact Index Per Article: 9.7] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/22/2022] Open
Abstract
Bacterial pathogens have coevolved with humans in order to efficiently infect, replicate within, and be transmitted to new hosts to ensure survival and a continual infection cycle. For enteric pathogens, the ability to adapt to numerous host factors under the harsh conditions of the gastrointestinal tract is critical for establishing infection. One such host factor readily encountered by enteric bacteria is bile, an innately antimicrobial detergent-like compound essential for digestion and nutrient absorption. Not only have enteric pathogens evolved to resist the bactericidal conditions of bile, but these bacteria also utilize bile as a signal to enhance virulence regulation for efficient infection. This review provides a comprehensive and up-to-date analysis of bile-related research with enteric pathogens. From common responses to the unique expression of specific virulence factors, each pathogen has overcome significant challenges to establish infection in the gastrointestinal tract. Utilization of bile as a signal to modulate virulence factor expression has led to important insights for our understanding of virulence mechanisms for many pathogens. Further research on enteric pathogens exposed to this in vivo signal will benefit therapeutic and vaccine development and ultimately enhance our success at combating such elite pathogens.
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Wallace N, Zani A, Abrams E, Sun Y. The Impact of Oxygen on Bacterial Enteric Pathogens. ADVANCES IN APPLIED MICROBIOLOGY 2016; 95:179-204. [PMID: 27261784 DOI: 10.1016/bs.aambs.2016.04.002] [Citation(s) in RCA: 7] [Impact Index Per Article: 0.9] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 02/07/2023]
Abstract
Bacterial enteric pathogens are responsible for a tremendous amount of foodborne illnesses every year through the consumption of contaminated food products. During their transit from contaminated food sources to the host gastrointestinal tract, these pathogens are exposed and must adapt to fluctuating oxygen levels to successfully colonize the host and cause diseases. However, the majority of enteric infection research has been conducted under aerobic conditions. To raise awareness of the importance in understanding the impact of oxygen, or lack of oxygen, on enteric pathogenesis, we describe in this review the metabolic and physiological responses of nine bacterial enteric pathogens exposed to environments with different oxygen levels. We further discuss the effects of oxygen levels on virulence regulation to establish potential connections between metabolic adaptations and bacterial pathogenesis. While not providing an exhaustive list of all bacterial pathogens, we highlight key differences and similarities among nine facultative anaerobic and microaerobic pathogens in this review to argue for a more in-depth understanding of the diverse impact oxygen levels have on enteric pathogenesis.
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Affiliation(s)
- N Wallace
- University of Dayton, Dayton, OH, United States
| | - A Zani
- University of Dayton, Dayton, OH, United States
| | - E Abrams
- University of Dayton, Dayton, OH, United States
| | - Y Sun
- University of Dayton, Dayton, OH, United States
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