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Ogunleye SC, Islam S, Chowdhury QMMK, Ozdemir O, Lawrence ML, Abdelhamed H. Catabolite control protein C contributes to virulence and hydrogen peroxide-induced oxidative stress responses in Listeria monocytogenes. Front Microbiol 2024; 15:1403694. [PMID: 38881664 PMCID: PMC11176438 DOI: 10.3389/fmicb.2024.1403694] [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: 03/19/2024] [Accepted: 05/07/2024] [Indexed: 06/18/2024] Open
Abstract
Listeria monocytogenes causes listeriosis, an infectious and potentially fatal disease of animals and humans. A diverse network of transcriptional regulators, including LysR-type catabolite control protein C (CcpC), is critical for the survival of L. monocytogenes and its ability to transition into the host environment. In this study, we explored the physiological and genetic consequences of deleting ccpC and the effects of such deletion on the ability of L. monocytogenes to cause disease. We found that ccpC deletion did not impact hemolytic activity, whereas it resulted in significant reductions in phospholipase activities. Western blotting revealed that the ΔccpC strain produced significantly reduced levels of the cholesterol-dependent cytolysin LLO relative to the wildtype F2365 strain. However, the ΔccpC mutant displayed no significant intracellular growth defect in macrophages. Furthermore, ΔccpC strain exhibited reduction in plaque numbers in fibroblasts compared to F2365, but plaque size was not significantly affected by ccpC deletion. In a murine model system, the ΔccpC strain exhibited a significantly reduced bacterial burden in the liver and spleen compared to the wildtype F2365 strain. Interestingly, the deletion of this gene also enhanced the survival of L. monocytogenes under conditions of H2O2-induced oxidative stress. Transcriptomic analyses performed under H2O2-induced oxidative stress conditions revealed that DNA repair, cellular responses to DNA damage and stress, metalloregulatory proteins, and genes involved in the biosynthesis of peptidoglycan and teichoic acids were significantly induced in the ccpC deletion strain relative to F2365. In contrast, genes encoding internalin, 1-phosphatidylinositol phosphodiesterase, and genes associated with sugar-specific phosphotransferase system components, porphyrin, branched-chain amino acids, and pentose phosphate pathway were significantly downregulated in the ccpC deletion strain relative to F2365. This finding highlights CcpC as a key factor that regulates L. monocytogenes physiology and responses to oxidative stress by controlling the expression of important metabolic pathways.
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Affiliation(s)
- Seto C Ogunleye
- Department of Comparative Biomedical Sciences, College of Veterinary Medicine, Mississippi State University, Mississippi, MS, United States
| | - Shamima Islam
- Department of Comparative Biomedical Sciences, College of Veterinary Medicine, Mississippi State University, Mississippi, MS, United States
| | - Q M Monzur Kader Chowdhury
- Department of Comparative Biomedical Sciences, College of Veterinary Medicine, Mississippi State University, Mississippi, MS, United States
| | - Ozan Ozdemir
- Department of Comparative Biomedical Sciences, College of Veterinary Medicine, Mississippi State University, Mississippi, MS, United States
| | - Mark L Lawrence
- Department of Comparative Biomedical Sciences, College of Veterinary Medicine, Mississippi State University, Mississippi, MS, United States
| | - Hossam Abdelhamed
- Department of Comparative Biomedical Sciences, College of Veterinary Medicine, Mississippi State University, Mississippi, MS, United States
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2
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Chowdhury B, Anand S. Environmental persistence of Listeria monocytogenes and its implications in dairy processing plants. Compr Rev Food Sci Food Saf 2023; 22:4573-4599. [PMID: 37680027 DOI: 10.1111/1541-4337.13234] [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: 01/25/2023] [Revised: 07/10/2023] [Accepted: 08/09/2023] [Indexed: 09/09/2023]
Abstract
Listeriosis, an invasive illness with a fatality rate between 20% and 30%, is caused by the ubiquitous bacterium Listeria monocytogenes. Human listeriosis has long been associated with foods. This is because the ubiquitous nature of the bacteria renders it a common food contaminant, posing a significant risk to the food processing sector. Although several sophisticated stress coping mechanisms have been identified as significant contributing factors toward the pathogen's persistence, a complete understanding of the mechanisms underlying persistence across various strains remains limited. Moreover, aside from genetic aspects that promote the ability to cope with stress, various environmental factors that exist in food manufacturing plants could also contribute to the persistence of the pathogen. The objective of this review is to provide insight into the challenges faced by the dairy industry because of the pathogens' environmental persistence. Additionally, it also aims to emphasize the diverse adaptation and response mechanisms utilized by L. monocytogenes in food manufacturing plants to evade environmental stressors. The persistence of L. monocytogenes in the food processing environment poses a serious threat to food safety and public health. The emergence of areas with high levels of L. monocytogenes contamination could facilitate Listeria transmission through aerosols, potentially leading to the recontamination of food, particularly from floors and drains, when sanitation is implemented alongside product manufacturing. Hence, to produce safe dairy products and reduce the frequency of outbreaks of listeriosis, it is crucial to understand the factors that contribute to the persistence of this pathogen and to implement efficient control strategies.
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Affiliation(s)
- Bhaswati Chowdhury
- Department of Dairy and Food Science, South Dakota State University, Brookings, South Dakota, USA
| | - Sanjeev Anand
- Department of Dairy and Food Science, South Dakota State University, Brookings, South Dakota, USA
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3
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Growth of Listeria monocytogenes is promoted at low temperature when exogenous unsaturated fatty acids are incorporated in its membrane. Food Microbiol 2023; 110:104170. [DOI: 10.1016/j.fm.2022.104170] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/16/2022] [Revised: 10/06/2022] [Accepted: 10/18/2022] [Indexed: 11/06/2022]
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4
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The Bacterial MtrAB Two-Component System Regulates the Cell Wall Homeostasis Responding to Environmental Alkaline Stress. Microbiol Spectr 2022; 10:e0231122. [PMID: 36073914 PMCID: PMC9602371 DOI: 10.1128/spectrum.02311-22] [Citation(s) in RCA: 16] [Impact Index Per Article: 8.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/04/2023] Open
Abstract
Throughout the course of evolution, bacteria have developed signal transduction tools such as two-component systems (TCSs) to meet their demands to thrive even under the most challenging environmental conditions. One TCS called MtrAB is commonly found in Actinobacteria and is implicated in cell wall metabolism, osmoprotection, cell proliferation, antigen secretion, and biosynthesis of secondary metabolites. However, precisely how the MtrAB TCS regulates the bacterial responses to external environments remains unclear. Here, we report that the MtrAB TCS regulates the cell envelope response of alkali-tolerant bacterium Dietzia sp. strain DQ12-45-1b to extreme alkaline stimuli. We found that under alkaline conditions, an mtrAB mutant exhibited both reduced growth and abnormal morphology compared to the wild-type strain. Electrophoretic mobility shift assay analysis showed that MtrA binds the promoter of the mraZ gene critical for cell wall homeostasis, suggesting that MtrA directly controls transcription of this regulator. In conclusion, our findings demonstrate that MtrAB TCS is involved in controlling the bacterial response to alkaline stimuli by regulating the expression of the cell wall homeostasis regulator MraZ in Dietzia sp. DQ12-45-1b, providing novel details critical for a mechanistic understanding of how cell wall homeostasis is controlled. IMPORTANCE Microorganisms can be found in most extreme environments, and they have to adapt to a wide range of environmental stresses. The two-component systems (TCSs) found in bacteria detect environmental stimuli and regulate physiological pathways for survival. The MtrAB TCS conserved in Corynebacterineae is critical for maintaining the metabolism of the cell wall components that protects bacteria from diverse environmental stresses. However, how the MtrAB TCS regulates cell wall homeostasis and adaptation under stress conditions is unclear. Here, we report that the MtrAB TCS in Dietzia sp. DQ12-45-1b plays a critical role in alkaline resistance by modulating the cell wall homeostasis through the MtrAB-MraZ pathway. Thus, our work provides a novel regulatory pathway used by bacteria for adaptation and survival under extreme alkaline stresses.
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5
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Sharma P, Mondal K, Kumar S, Tamang S, Najar IN, Das S, Thakur N. RNA thermometers in bacteria: Role in thermoregulation. BIOCHIMICA ET BIOPHYSICA ACTA (BBA) - GENE REGULATORY MECHANISMS 2022; 1865:194871. [DOI: 10.1016/j.bbagrm.2022.194871] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [Track Full Text] [Subscribe] [Scholar Register] [Received: 06/30/2022] [Revised: 08/09/2022] [Accepted: 08/21/2022] [Indexed: 04/09/2023]
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6
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Anast JM, Etter AJ, Schmitz‐Esser S. Comparative analysis of
Listeria monocytogenes
plasmid transcriptomes reveals common and plasmid‐specific gene expression patterns and high expression of noncoding RNAs. Microbiologyopen 2022; 11:e1315. [PMID: 36314750 PMCID: PMC9484302 DOI: 10.1002/mbo3.1315] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/18/2022] [Revised: 08/31/2022] [Accepted: 08/31/2022] [Indexed: 11/09/2022] Open
Abstract
Recent research demonstrated that some Listeria monocytogenes plasmids contribute to stress survival. However, only a few studies have analyzed gene expression patterns of L. monocytogenes plasmids. In this study, we identified four previously published stress‐response‐associated transcriptomic data sets which studied plasmid‐harboring L. monocytogenes strains but did not include an analysis of the plasmid transcriptomes. The four transcriptome data sets encompass three distinct plasmids from three different L. monocytogenes strains. Differential gene expression analysis of these plasmids revealed that the number of differentially expressed (DE) L. monocytogenes plasmid genes ranged from 30 to 45 with log2 fold changes of −2.2 to 6.8, depending on the plasmid. Genes often found to be DE included the cadmium resistance genes cadA and cadC, a gene encoding a putative NADH peroxidase, the putative ultraviolet resistance gene uvrX, and several uncharacterized noncoding RNAs (ncRNAs). Plasmid‐encoded ncRNAs were consistently among the highest expressed genes. In addition, one of the data sets utilized the same experimental conditions for two different strains harboring distinct plasmids. We found that the gene expression patterns of these two L. monocytogenes plasmids were highly divergent despite the identical treatments. These data suggest plasmid‐specific gene expression responses to environmental stimuli and differential plasmid regulation mechanisms between L. monocytogenes strains. Our findings further our understanding of the dynamic expression of L. monocytogenes plasmid‐encoded genes in diverse environmental conditions and highlight the need to expand the study of L. monocytogenes plasmid genes' functions.
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Affiliation(s)
- Justin M. Anast
- Department of Animal Science Iowa State University Ames Iowa USA
- Interdepartmental Microbiology Graduate Program Iowa State University Ames Iowa USA
| | - Andrea J. Etter
- Department of Nutrition and Food Sciences The University of Vermont Burlington Vermont USA
| | - Stephan Schmitz‐Esser
- Department of Animal Science Iowa State University Ames Iowa USA
- Interdepartmental Microbiology Graduate Program Iowa State University Ames Iowa USA
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He S, Cui Y, Dong R, Chang J, Cai H, Liu H, Shi X. Global transcriptomic analysis of ethanol tolerance response in Salmonella Enteritidis. Curr Res Food Sci 2022; 5:798-806. [PMID: 35600539 PMCID: PMC9114158 DOI: 10.1016/j.crfs.2022.04.011] [Citation(s) in RCA: 6] [Impact Index Per Article: 3.0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/31/2021] [Revised: 04/07/2022] [Accepted: 04/26/2022] [Indexed: 11/03/2022] Open
Abstract
Adaptation to sublethal amounts of ethanol enables Salmonella Enteritidis to survive under normally lethal ethanol conditions, which is referred to as the ethanol tolerance response (ETR). To uncover mechanisms underlying this adaptative response, RNA-seq and RT-qPCR techniques were employed to reveal global gene expression patterns in S. Enteritidis after sublethal ethanol treatment. It was observed that 811 genes were significantly differentially expressed in ethanol-treated cells compared with control cells, among which 328 were up-regulated and 483 were down-regulated. Functional analysis revealed that these genes were enriched in different pathways, including signal transduction, membrane transport, metabolism, transcription, translation, and cell motility. Specifically, a couple of genes encoding histidine kinases and response regulators in two-component systems were up-regulated to activate sensing and signaling pathways. Membrane function was also influenced by ethanol treatment since ABC transporter genes for transport of glutamate, phosphate, 2-aminoethylphosphonate, and osmoprotectant were up-regulated, while those for transport of iron complex, manganese, and ribose were down-regulated. Accompanied with this, diverse gene expression alterations related to the metabolism of amino acids, carbohydrates, vitamins, and nucleotides were observed, which suggested nutritional requirements for S. Enteritidis to mount the ETR. Furthermore, genes associated with ribosomal units, bacterial chemotaxis, and flagellar assembly were generally repressed as a possible energy conservation strategy. Taken together, this transcriptomic study indicates that S. Enteritidis employs multiple genes and adaptation pathways to develop the ETR. A total of 811 genes were involved in ethanol tolerance of Salmonella Enteritidis. Certain genes encoding two-component signaling systems were upregulated. Differential expression of many metabolism-related genes was observed. Bacterial chemotaxis and flagellar assembly were repressed by ethanol stress. Diverse membrane transport functions were influenced by ethanol stress.
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8
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TMT proteomic analysis for molecular mechanism of Staphylococcus aureus in response to freezing stress. Appl Microbiol Biotechnol 2022; 106:3139-3152. [PMID: 35460349 DOI: 10.1007/s00253-022-11927-w] [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: 01/04/2022] [Revised: 04/07/2022] [Accepted: 04/11/2022] [Indexed: 11/02/2022]
Abstract
The foodborne pathogen Staphylococcus aureus continues to challenge the food industry due to the pathogenicity and tolerance of the bacterium. As a common storage condition for frozen food during transportation, distribution, and storage, freezing does not seem to be entirely safe due to the cold tolerance of S. aureus. In addition, our study indicated that the biofilm formation ability of S. aureus was significantly increased in response to freezing stress. To explore the molecular mechanism regulating the response to freezing stress, the proteomics signature of S. aureus after freezing stress based on tandem mass tag (TMT) labeling and liquid chromatography tandem mass spectrometry (LC-MS/MS) was analyzed. Gene Ontology and pathway analysis revealed that ribosome function, metabolism, RNA repair, and stress response proteins were differentially regulated (P < 0.05). Furthermore, transpeptidase sortase A, biofilm operon icaADBC HTH-type negative transcriptional regulator IcaR, and HTH-type transcriptional regulator MgrA were involved in the modulation of increased biofilm formation in response to freezing stress (P < 0.05). Moreover, significant lysine acetylation and malonylation signals in the S. aureus response to freezing stress were observed. Collectively, the current work provides additional insight for comprehending the molecular mechanism of S. aureus in response to freezing stress and presents potential targets for developing strategies to control S. aureus. KEY POINTS: • TMT proteomic analysis was first used on S. aureus in response to freezing stress. • Ribosome-, metabolism-, and biofilm-related proteins change after freezing stress. • Increased biofilm formation in S. aureus responded to freezing stress.
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9
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Chazan A, Rozenberg A, Mannen K, Nagata T, Tahan R, Yaish S, Larom S, Inoue K, Béjà O, Pushkarev A. Diverse heliorhodopsins detected via functional metagenomics in freshwater Actinobacteria, Chloroflexi and Archaea. Environ Microbiol 2022; 24:110-121. [PMID: 34984789 DOI: 10.1111/1462-2920.15890] [Citation(s) in RCA: 9] [Impact Index Per Article: 4.5] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/03/2021] [Revised: 11/29/2021] [Accepted: 12/26/2021] [Indexed: 12/25/2022]
Abstract
The recently discovered rhodopsin family of heliorhodopsins (HeRs) is abundant in diverse microbial environments. So far, the functional and biological roles of HeRs remain unknown. To tackle this issue, we combined experimental and computational screens to gain some novel insights. Here, 10 readily expressed HeR genes were found using functional metagenomics on samples from two freshwater environments. These HeRs originated from diverse prokaryotic groups: Actinobacteria, Chloroflexi and Archaea. Heterologously expressed HeRs absorbed light in the green and yellow wavelengths (543-562 nm) and their photocycles exhibited diverse kinetic characteristics. To approach the physiological function of the HeRs, we used our environmental clones along with thousands of microbial genomes to analyze genes neighbouring HeRs. The strongest association was found with the DegV family involved in activation of fatty acids, which allowed us to hypothesize that HeRs might be involved in light-induced membrane lipid modifications.
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Affiliation(s)
- Ariel Chazan
- Faculty of Biology, Technion - Israel Institute of Technology, Haifa, 32000, Israel
| | - Andrey Rozenberg
- Faculty of Biology, Technion - Israel Institute of Technology, Haifa, 32000, Israel
| | - Kentaro Mannen
- The Institute for Solid State Physics, The University of Tokyo, 5-1-5 Kashiwanoha, Kashiwa, Chiba, 277-8581, Japan
| | - Takashi Nagata
- The Institute for Solid State Physics, The University of Tokyo, 5-1-5 Kashiwanoha, Kashiwa, Chiba, 277-8581, Japan.,PRESTO, Japan Science and Technology Agency, 4-1-8 Honcho, Kawaguchi, Saitama, 332-0012, Japan
| | - Ran Tahan
- Faculty of Biology, Technion - Israel Institute of Technology, Haifa, 32000, Israel
| | - Shir Yaish
- Faculty of Biology, Technion - Israel Institute of Technology, Haifa, 32000, Israel
| | - Shirley Larom
- Faculty of Biology, Technion - Israel Institute of Technology, Haifa, 32000, Israel
| | - Keiichi Inoue
- The Institute for Solid State Physics, The University of Tokyo, 5-1-5 Kashiwanoha, Kashiwa, Chiba, 277-8581, Japan.,PRESTO, Japan Science and Technology Agency, 4-1-8 Honcho, Kawaguchi, Saitama, 332-0012, Japan
| | - Oded Béjà
- Faculty of Biology, Technion - Israel Institute of Technology, Haifa, 32000, Israel
| | - Alina Pushkarev
- Faculty of Biology, Technion - Israel Institute of Technology, Haifa, 32000, Israel
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10
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Quereda JJ, Morón-García A, Palacios-Gorba C, Dessaux C, García-del Portillo F, Pucciarelli MG, Ortega AD. Pathogenicity and virulence of Listeria monocytogenes: A trip from environmental to medical microbiology. Virulence 2021; 12:2509-2545. [PMID: 34612177 PMCID: PMC8496543 DOI: 10.1080/21505594.2021.1975526] [Citation(s) in RCA: 64] [Impact Index Per Article: 21.3] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/04/2020] [Revised: 08/23/2021] [Accepted: 08/25/2021] [Indexed: 01/02/2023] Open
Abstract
Listeria monocytogenes is a saprophytic gram-positive bacterium, and an opportunistic foodborne pathogen that can produce listeriosis in humans and animals. It has evolved an exceptional ability to adapt to stress conditions encountered in different environments, resulting in a ubiquitous distribution. Because some food preservation methods and disinfection protocols in food-processing environments cannot efficiently prevent contaminations, L. monocytogenes constitutes a threat to human health and a challenge to food safety. In the host, Listeria colonizes the gastrointestinal tract, crosses the intestinal barrier, and disseminates through the blood to target organs. In immunocompromised individuals, the elderly, and pregnant women, the pathogen can cross the blood-brain and placental barriers, leading to neurolisteriosis and materno-fetal listeriosis. Molecular and cell biology studies of infection have proven L. monocytogenes to be a versatile pathogen that deploys unique strategies to invade different cell types, survive and move inside the eukaryotic host cell, and spread from cell to cell. Here, we present the multifaceted Listeria life cycle from a comprehensive perspective. We discuss genetic features of pathogenic Listeria species, analyze factors involved in food contamination, and review bacterial strategies to tolerate stresses encountered both during food processing and along the host's gastrointestinal tract. Then we dissect host-pathogen interactions underlying listerial pathogenesis in mammals from a cell biology and systemic point of view. Finally, we summarize the epidemiology, pathophysiology, and clinical features of listeriosis in humans and animals. This work aims to gather information from different fields crucial for a comprehensive understanding of the pathogenesis of L. monocytogenes.
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Affiliation(s)
- Juan J. Quereda
- Departamento de Producción y Sanidad Animal, Salud Pública Veterinaria y Ciencia y Tecnología de los Alimentos, Facultad de Veterinaria, Universidad Cardenal Herrera-CEU, CEU Universities. Valencia, Spain
| | - Alvaro Morón-García
- Departamento de Biología Celular. Facultad de Ciencias Biológicas, Universidad Complutense de Madrid. Madrid, Spain
| | - Carla Palacios-Gorba
- Departamento de Producción y Sanidad Animal, Salud Pública Veterinaria y Ciencia y Tecnología de los Alimentos, Facultad de Veterinaria, Universidad Cardenal Herrera-CEU, CEU Universities. Valencia, Spain
| | - Charlotte Dessaux
- Departamento de Biotecnología Microbiana, Centro Nacional de Biotecnología (CNB)- Consejo Superior De Investigaciones Científicas (CSIC), Madrid, Spain
| | - Francisco García-del Portillo
- Departamento de Biotecnología Microbiana, Centro Nacional de Biotecnología (CNB)- Consejo Superior De Investigaciones Científicas (CSIC), Madrid, Spain
| | - M. Graciela Pucciarelli
- Departamento de Biotecnología Microbiana, Centro Nacional de Biotecnología (CNB)- Consejo Superior De Investigaciones Científicas (CSIC), Madrid, Spain
- Centro de Biología Molecular ‘Severo Ochoa’. Departamento de Biología Molecular, Facultad de Ciencias, Universidad Autónoma de Madrid. Madrid, Spain
| | - Alvaro D. Ortega
- Departamento de Biología Celular. Facultad de Ciencias Biológicas, Universidad Complutense de Madrid. Madrid, Spain
- Departamento de Biotecnología Microbiana, Centro Nacional de Biotecnología (CNB)- Consejo Superior De Investigaciones Científicas (CSIC), Madrid, Spain
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11
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Gray J, Chandry PS, Kaur M, Kocharunchitt C, Fanning S, Bowman JP, Fox EM. Colonisation dynamics of Listeria monocytogenes strains isolated from food production environments. Sci Rep 2021; 11:12195. [PMID: 34108547 PMCID: PMC8190317 DOI: 10.1038/s41598-021-91503-w] [Citation(s) in RCA: 6] [Impact Index Per Article: 2.0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/24/2021] [Accepted: 05/06/2021] [Indexed: 12/19/2022] Open
Abstract
Listeria monocytogenes is a ubiquitous bacterium capable of colonising and persisting within food production environments (FPEs) for many years, even decades. This ability to colonise, survive and persist within the FPEs can result in food product cross-contamination, including vulnerable products such as ready to eat food items. Various environmental and genetic elements are purported to be involved, with the ability to form biofilms being an important factor. In this study we examined various mechanisms which can influence colonisation in FPEs. The ability of isolates (n = 52) to attach and grow in biofilm was assessed, distinguishing slower biofilm formers from isolates forming biofilm more rapidly. These isolates were further assessed to determine if growth rate, exopolymeric substance production and/or the agr signalling propeptide influenced these dynamics and could promote persistence in conditions reflective of FPE. Despite no strong association with the above factors to a rapid colonisation phenotype, the global transcriptome suggested transport, energy production and metabolism genes were widely upregulated during the initial colonisation stages under nutrient limited conditions. However, the upregulation of the metabolism systems varied between isolates supporting the idea that L. monocytogenes ability to colonise the FPEs is strain-specific.
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Affiliation(s)
- Jessica Gray
- CSIRO Agriculture and Food, Werribee, VIC, Australia. .,Food Safety Centre, Tasmanian Institute of Agriculture, School of Land and Food, University of Tasmania, Hobart, TAS, Australia.
| | | | - Mandeep Kaur
- Biosciences and Food Technology, School of Science, RMIT University, Melbourne, VIC, Australia
| | - Chawalit Kocharunchitt
- Food Safety Centre, Tasmanian Institute of Agriculture, School of Land and Food, University of Tasmania, Hobart, TAS, Australia
| | - Séamus Fanning
- UCD-Centre for Food Safety, School of Public Health, Physiotherapy and Sports Science, University College Dublin, Dublin, D04 N2E5, Ireland.,Institute for Global Food Security, Queen's University Belfast, Chlorine Gardens, Belfast, BT5 6AG, UK
| | - John P Bowman
- Food Safety Centre, Tasmanian Institute of Agriculture, School of Land and Food, University of Tasmania, Hobart, TAS, Australia
| | - Edward M Fox
- CSIRO Agriculture and Food, Werribee, VIC, Australia. .,Department of Applied Sciences, Northumbria University, Newcastle upon Tyne, NE1 8ST, UK.
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12
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Prentice MB. Bacterial microcompartments and their role in pathogenicity. Curr Opin Microbiol 2021; 63:19-28. [PMID: 34107380 DOI: 10.1016/j.mib.2021.05.009] [Citation(s) in RCA: 5] [Impact Index Per Article: 1.7] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/07/2020] [Revised: 04/26/2021] [Accepted: 05/17/2021] [Indexed: 02/08/2023]
Abstract
Catabolic bacterial microcompartments (BMC), or metabolosomes, are self-assembling structures formed by enzymes enclosed by porous protein shells. They provide a specialised environment inside bacterial cells separating a short catabolic pathway with reactive or toxic intermediates from the cytoplasm. Substrates for microcompartment metabolism like ethanolamine and 1,2-propanediol are constantly produced in the human intestine by bacterial metabolism of food or host cell components. Enteric pathogens gain a competitive advantage in the intestine by metabolising these substrates, an advantage enhanced by the host inflammatory response. They exploit the intestinal specificity of signature metabolosome substrates by adopting substrate sensors and regulators encoded by BMC operons for governance of non-metabolic processes in pathogenesis. In turn, products of microcompartment metabolism regulate the host immune system.
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Affiliation(s)
- Michael B Prentice
- Department of Pathology, University College Cork, Cork, Ireland; School of Microbiology, University College Cork, Cork, Ireland; APC Microbiome Ireland, University College Cork, Ireland.
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13
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Listeria monocytogenes Cold Shock Proteins: Small Proteins with A Huge Impact. Microorganisms 2021; 9:microorganisms9051061. [PMID: 34068949 PMCID: PMC8155936 DOI: 10.3390/microorganisms9051061] [Citation(s) in RCA: 17] [Impact Index Per Article: 5.7] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/24/2021] [Revised: 05/11/2021] [Accepted: 05/12/2021] [Indexed: 01/26/2023] Open
Abstract
Listeria monocytogenes has evolved an extensive array of mechanisms for coping with stress and adapting to changing environmental conditions, ensuring its virulence phenotype expression. For this reason, L. monocytogenes has been identified as a significant food safety and public health concern. Among these adaptation systems are cold shock proteins (Csps), which facilitate rapid response to stress exposure. L. monocytogenes has three highly conserved csp genes, namely, cspA, cspB, and cspD. Using a series of csp deletion mutants, it has been shown that L. monocytogenes Csps are important for biofilm formation, motility, cold, osmotic, desiccation, and oxidative stress tolerance. Moreover, they are involved in overall virulence by impacting the expression of virulence-associated phenotypes, such as hemolysis and cell invasion. It is postulated that during stress exposure, Csps function to counteract harmful effects of stress, thereby preserving cell functions, such as DNA replication, transcription and translation, ensuring survival and growth of the cell. Interestingly, it seems that Csps might suppress tolerance to some stresses as their removal resulted in increased tolerance to stresses, such as desiccation for some strains. Differences in csp roles among strains from different genetic backgrounds are apparent for desiccation tolerance and biofilm production. Additionally, hierarchical trends for the different Csps and functional redundancies were observed on their influences on stress tolerance and virulence. Overall current data suggest that Csps have a wider role in bacteria physiology than previously assumed.
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14
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Anast JM, Bobik TA, Schmitz-Esser S. The Cobalamin-Dependent Gene Cluster of Listeria monocytogenes: Implications for Virulence, Stress Response, and Food Safety. Front Microbiol 2020; 11:601816. [PMID: 33240255 PMCID: PMC7677406 DOI: 10.3389/fmicb.2020.601816] [Citation(s) in RCA: 9] [Impact Index Per Article: 2.3] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/01/2020] [Accepted: 10/19/2020] [Indexed: 12/21/2022] Open
Abstract
Several genes of the eut, pdu, and cob/cbi operons are responsible for the metabolism of ethanolamine (EA) and 1,2-propanediol (PD) and are essential during the pathogenic lifecycles of various enteric pathogens. Studies concerning EA and PD metabolism have primarily focused on bacterial genera from the family Enterobacteriaceae, especially the genus Salmonella. Listeria monocytogenes is a member of the Firmicutes phylum and is the causative agent of the rare but highly fatal foodborne disease listeriosis. The eut, pdu, and cob/cbi operons are organized as a single large locus collectively referred to as the cobalamin-dependent gene cluster (CDGC). The CDGC is well conserved in L. monocytogenes; however, functional characterization of the genes in this cluster and how they may contribute to Listeria virulence and stress tolerance in food production environments is highly limited. Previous work suggests that the degradation pathway of PD is essential for L. monocytogenes establishment in the gastrointestinal tract. In contrast, EA metabolism may be more important during intracellular replication. Other studies indicate that the CDGC is utilized when L. monocytogenes is exposed to food and food production relevant stress conditions. Perhaps most noteworthy, L. monocytogenes exhibits attenuated growth at cold temperatures when a key EA utilization pathway gene was deleted. This review aims to summarize the current knowledge of these pathways in L. monocytogenes and their significance in virulence and stress tolerance, especially considering recent developments.
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Affiliation(s)
- Justin M Anast
- Interdepartmental Microbiology Graduate Program, Iowa State University, Ames, IA, United States.,Department of Animal Science, Iowa State University, Ames, IA, United States
| | - Thomas A Bobik
- Interdepartmental Microbiology Graduate Program, Iowa State University, Ames, IA, United States.,Roy J. Carver Department of Biochemistry, Biophysics and Molecular Biology, Iowa State University, Ames, IA, United States
| | - Stephan Schmitz-Esser
- Interdepartmental Microbiology Graduate Program, Iowa State University, Ames, IA, United States.,Department of Animal Science, Iowa State University, Ames, IA, United States
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15
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Cold-shock proteins affect desiccation tolerance, biofilm formation and motility in Listeria monocytogenes. Int J Food Microbiol 2020; 329:108662. [DOI: 10.1016/j.ijfoodmicro.2020.108662] [Citation(s) in RCA: 12] [Impact Index Per Article: 3.0] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/28/2020] [Revised: 05/13/2020] [Accepted: 05/14/2020] [Indexed: 12/30/2022]
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16
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The transcriptome of Listeria monocytogenes during co-cultivation with cheese rind bacteria suggests adaptation by induction of ethanolamine and 1,2-propanediol catabolism pathway genes. PLoS One 2020; 15:e0233945. [PMID: 32701964 PMCID: PMC7377500 DOI: 10.1371/journal.pone.0233945] [Citation(s) in RCA: 14] [Impact Index Per Article: 3.5] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/15/2020] [Accepted: 07/01/2020] [Indexed: 02/07/2023] Open
Abstract
The survival of Listeria (L.) monocytogenes in foods and food production environments (FPE) is dependent on several genes that increase tolerance to stressors; this includes competing with intrinsic bacteria. We aimed to uncover genes that are differentially expressed (DE) in L. monocytogenes sequence type (ST) 121 strain 6179 when co-cultured with cheese rind bacteria. L. monocytogenes was cultivated in broth or on plates with either a Psychrobacter or Brevibacterium isolate from cheese rinds. RNA was extracted from co-cultures in broth after two or 12 hours and from plates after 24 and 72 hours. Broth co-cultivations with Brevibacterium or Psychrobacter yielded up to 392 and 601 DE genes, while plate co-cultivations significantly affected the expression of up to 190 and 485 L. monocytogenes genes, respectively. Notably, the transcription of virulence genes encoding the Listeria adhesion protein and Listeriolysin O were induced during plate and broth co-cultivations. The expression of several systems under the control of the global stress gene regulator, σB, increased during co-cultivation. A cobalamin-dependent gene cluster, responsible for the catabolism of ethanolamine and 1,2-propanediol, was upregulated in both broth and plate co-cultures conditions. Finally, a small non-coding (nc)RNA, Rli47, was induced after 72 hours of co-cultivation on plates and accounted for 50-90% of the total reads mapped to L. monocytogenes. A recent study has shown that Rli47 may contribute to L. monocytogenes stress survival by slowing growth during stress conditions through the suppression of branch-chained amino acid biosynthesis. We hypothesize that Rli47 may have an impactful role in the response of L. monocytogenes to co-cultivation by regulating a complex network of metabolic and virulence mechanisms.
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17
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Alves Â, Magalhães R, Brandão TR, Pimentel L, Rodríguez-Alcalá LM, Teixeira P, Ferreira V. Impact of exposure to cold and cold-osmotic stresses on virulence-associated characteristics of Listeria monocytogenes strains. Food Microbiol 2020; 87:103351. [DOI: 10.1016/j.fm.2019.103351] [Citation(s) in RCA: 16] [Impact Index Per Article: 4.0] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/03/2019] [Revised: 10/08/2019] [Accepted: 10/18/2019] [Indexed: 11/26/2022]
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18
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He S, Fong K, Wang S, Shi X. Ethanol adaptation in foodborne bacterial pathogens. Crit Rev Food Sci Nutr 2020; 61:777-787. [DOI: 10.1080/10408398.2020.1746628] [Citation(s) in RCA: 6] [Impact Index Per Article: 1.5] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/27/2022]
Affiliation(s)
- Shoukui He
- MOST-USDA Joint Research Center for Food Safety, School of Agriculture and Biology, State Key Lab of Microbial Metabolism, Shanghai Jiao Tong University, Shanghai, China
- Food, Nutrition and Health, Faculty of Land and Food Systems, The University of British Columbia, Vancouver, Canada
| | - Karen Fong
- Food, Nutrition and Health, Faculty of Land and Food Systems, The University of British Columbia, Vancouver, Canada
| | - Siyun Wang
- Food, Nutrition and Health, Faculty of Land and Food Systems, The University of British Columbia, Vancouver, Canada
| | - Xianming Shi
- MOST-USDA Joint Research Center for Food Safety, School of Agriculture and Biology, State Key Lab of Microbial Metabolism, Shanghai Jiao Tong University, Shanghai, China
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19
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Bacteriocin enterocin CRL35 is a modular peptide that induces non-bilayer states in bacterial model membranes. BIOCHIMICA ET BIOPHYSICA ACTA-BIOMEMBRANES 2020; 1862:183135. [DOI: 10.1016/j.bbamem.2019.183135] [Citation(s) in RCA: 11] [Impact Index Per Article: 2.8] [Reference Citation Analysis] [Track Full Text] [Subscribe] [Scholar Register] [Received: 06/28/2019] [Revised: 10/07/2019] [Accepted: 11/04/2019] [Indexed: 11/17/2022]
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20
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Kragh ML, Truelstrup Hansen L. Initial Transcriptomic Response and Adaption of Listeria monocytogenes to Desiccation on Food Grade Stainless Steel. Front Microbiol 2020; 10:3132. [PMID: 32038566 PMCID: PMC6987299 DOI: 10.3389/fmicb.2019.03132] [Citation(s) in RCA: 9] [Impact Index Per Article: 2.3] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/17/2019] [Accepted: 12/26/2019] [Indexed: 12/14/2022] Open
Abstract
The foodborne pathogen Listeria monocytogenes survives exposure to a variety of stresses including desiccation in the food industry. Strand-specific RNA sequencing was applied to analyze changes in the transcriptomes of two strains of L. monocytogenes (Lm 568 and Lm 08-5578) during desiccation [15°C, 43% relative humidity (RH)] on food grade stainless steel surfaces over 48 h to simulate a weekend with no food production. Both strains showed similar survival during desiccation with a 1.8-2 Log CFU/cm2 reduction after 48 h. Analysis of differentially expressed (DE) genes (>twofold, adjusted p-value <0.05) revealed that the initial response to desiccation was established after 6 h and remained constant with few new genes being DE after 12, 24, and 48 h. A core of 81 up- and 73 down-regulated DE genes were identified as a shared, strain independent response to desiccation. Among common upregulated genes were energy and oxidative stress related genes e.g., qoxABCD (cytochrome aa3) pdhABC (pyruvate dehydrogenase complex) and mntABCH (manganese transporter). Common downregulated genes related to anaerobic growth, proteolysis and the two component systems lmo1172/lmo1173 and cheA/cheY, which are involved in cold growth and flagellin production, respectively. Both strains upregulated additional genes involved in combatting oxidative stress and reactive oxygen species (ROS), including sod (superoxide dismutase), kat (catalase), tpx (thiol peroxidase) and several thioredoxins including trxAB, lmo2390 and lmo2830. Osmotic stress related genes were also upregulated in both strains, including gbuABC (glycine betaine transporter) and several chaperones clpC, cspA, and groE. Significant strain differences were also detected with the food outbreak strain Lm 08-5578 differentially expressing 1.9 × more genes (726) compared to Lm 568 (410). Unique to Lm 08-5578 was a significant upregulation of the expression of the alternative transcription factor σB and its regulon. A number of long antisense transcripts (lasRNA) were upregulated during desiccation including anti0605, anti0936, anti1846, and anti0777, with the latter controlling flagellum biosynthesis and possibly the downregulation of motility genes observed in both strains. This exploration of the transcriptomes of desiccated L. monocytogenes provides further understanding of how this bacterium encounters and survives the stress faced when exposed to dry conditions in the food industry.
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21
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Cortes BW, Naditz AL, Anast JM, Schmitz-Esser S. Transcriptome Sequencing of Listeria monocytogenes Reveals Major Gene Expression Changes in Response to Lactic Acid Stress Exposure but a Less Pronounced Response to Oxidative Stress. Front Microbiol 2020; 10:3110. [PMID: 32038553 PMCID: PMC6985202 DOI: 10.3389/fmicb.2019.03110] [Citation(s) in RCA: 26] [Impact Index Per Article: 6.5] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/09/2019] [Accepted: 12/23/2019] [Indexed: 12/15/2022] Open
Abstract
Listeria monocytogenes is a well-characterized pathogen that represents a major threat to food safety. In this study, we examine the chromosomal and plasmid transcriptomes of two different L. monocytogenes strains, 6179 [belonging to sequence type (ST) 121] and R479a (ST8), in response to 30 min exposure to oxidative (0.01% hydrogen peroxide) and acid (1% lactic acid, pH 3.4) stress. The exposure to oxidative stress resulted in 102 and 9 differentially expressed (DE) genes in the chromosomal transcriptomes of 6179 and R479a, respectively. In contrast, 2280 and 2151 DE genes were observed in the respective chromosomal transcriptomes of 6179 and R479a in response to lactic acid stress. During lactic acid stress, we observed upregulation of numerous genes known to be involved in the L. monocytogenes stress response, including multiple members of the σB regulon, many of which have not been functionally characterized. Among these genes, homologs of lmo2230 were highly upregulated in both strains. Most notably, the σB-dependent non-coding RNA Rli47 was by far the most highly expressed gene in both 6179 and R479a, accounting for an average of 28 and 38% of all mapped reads in the respective chromosomal transcriptomes. In response to oxidative stress, one DE gene was identified in the 6179 plasmid transcriptome, and no DE genes were observed in the transcriptome of the R479a plasmid. However, lactic acid exposure resulted in upregulation of the stress response gene clpL, among others, on the 6179 plasmid. In R479a, a number of uncharacterized plasmid genes were upregulated, indicating a potential role in stress response. Furthermore, an average of 65% of all mapped transcriptome reads for the R479a plasmid following acid stress were mapped to an intergenic region bearing similarity to riboswitches involved in transition metal resistance. The results of this study support the conclusion that members of the σB regulon, particularly lmo2230 and the non-coding RNA Rli47, play an integral role in the response of L. monocytogenes to acid stress. Furthermore, we report the first global transcriptome sequencing analysis of L. monocytogenes plasmid gene expression and identify a putative, plasmid-encoded riboswitch with potential involvement in response to acid exposure.
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Affiliation(s)
- Bienvenido W Cortes
- Interdepartmental Microbiology Graduate Program, Iowa State University, Ames, IA, United States.,Department of Animal Science, Iowa State University, Ames, IA, United States
| | - Annabel L Naditz
- Interdepartmental Microbiology Graduate Program, Iowa State University, Ames, IA, United States.,Department of Animal Science, Iowa State University, Ames, IA, United States
| | - Justin M Anast
- Interdepartmental Microbiology Graduate Program, Iowa State University, Ames, IA, United States.,Department of Animal Science, Iowa State University, Ames, IA, United States
| | - Stephan Schmitz-Esser
- Interdepartmental Microbiology Graduate Program, Iowa State University, Ames, IA, United States.,Department of Animal Science, Iowa State University, Ames, IA, United States
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22
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Sheet S, Yesupatham S, Ghosh K, Choi MS, Shim KS, Lee YS. Modulatory effect of low-shear modeled microgravity on stress resistance, membrane lipid composition, virulence, and relevant gene expression in the food-borne pathogen Listeria monocytogenes. Enzyme Microb Technol 2019; 133:109440. [PMID: 31874690 DOI: 10.1016/j.enzmictec.2019.109440] [Citation(s) in RCA: 8] [Impact Index Per Article: 1.6] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/17/2019] [Revised: 09/27/2019] [Accepted: 10/04/2019] [Indexed: 12/17/2022]
Abstract
The present study investigated the influence of low-shear modeled microgravity (LSMMG) conditions on Listeria monocytogenes stress response (heat, cold, and acid), membrane fatty acid composition, and virulence potential as well as stress-/virulence-associated gene expression. The results showed that LSMMG-cultivated cells had lower survival rate and lower D-values under heat and acid stress conditions compared to cells grown under normal gravity (NG). Interestingly, the cold resistance was elevated in cells cultivated under LSMMG conditions when compared to NG conditions. A higher amount of anteiso-branched chain fatty acids and lower ratio of iso/anteiso were observed in LSMMG cultured cells, which would contribute to increased membrane fluidity. Under LSMMG conditions, upregulated expression of cold stress-related genes (cspA, cspB, and cspD) was noticed but no change in expression was observed for heat (dnaK, groES, clpC, clpP, and clpE) and acid stress-related genes (sigB). The LSMMG-grown cells showed inferior virulence capacity in terms of infection, cell cycle arrest, and apoptosis induction in Caco-2 cells compared to those grown under NG conditions. Approximately 3.65, 2.13, 4.02, and 2.65-fold downregulation of prfA, hly, inlA, and bsh genes, respectively, in LSMMG-cultured cells might be the reason for reduced virulence. In conclusion, these findings suggest that growth under LSMMG conditions stimulates alterations in L. monocytogenes stress/virulence response, perhaps due to changes in lipid composition and related genes expression.
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Affiliation(s)
- Sunirmal Sheet
- Department of Forest Science and Technology, College of Agriculture and Life Sciences,Chonbuk National University, 567 Baekje-daero, Deokjin-gu, Jeonju-si, Jeollabuk-do, Republic of Korea
| | - Sathishkumar Yesupatham
- Department of Forest Science and Technology, College of Agriculture and Life Sciences,Chonbuk National University, 567 Baekje-daero, Deokjin-gu, Jeonju-si, Jeollabuk-do, Republic of Korea; Department of Biological Sciences, Korea Advanced Institute of Science and Technology, Daehak-Ro, Daejeon, Republic of Korea
| | - Kuntal Ghosh
- Department of Biological Sciences, Midnapore City College, Kuturiya, P.O. Bhadutala, Pin-721129, Paschim Medinipur, West Bengal, India
| | - Mi-Sook Choi
- Department of Forest Science and Technology, College of Agriculture and Life Sciences,Chonbuk National University, 567 Baekje-daero, Deokjin-gu, Jeonju-si, Jeollabuk-do, Republic of Korea
| | - Kwan Seob Shim
- Department of Animal Biotechnology, College of Agriculture and Life Sciences, Chonbuk National University, 567 Baekje-daero, Deokjin-gu, Jeonju-si, Jeollabuk-do, Republic of Korea
| | - Yang Soo Lee
- Department of Forest Science and Technology, College of Agriculture and Life Sciences,Chonbuk National University, 567 Baekje-daero, Deokjin-gu, Jeonju-si, Jeollabuk-do, Republic of Korea.
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23
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Hingston PA, Truelstrup Hansen L, Pombert JF, Wang S. Characterization of Listeria monocytogenes enhanced cold-tolerance variants isolated during prolonged cold storage. Int J Food Microbiol 2019; 306:108262. [PMID: 31362162 DOI: 10.1016/j.ijfoodmicro.2019.108262] [Citation(s) in RCA: 5] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/22/2019] [Revised: 05/04/2019] [Accepted: 07/07/2019] [Indexed: 11/25/2022]
Abstract
In this study, we show that growth and prolonged storage of Listeria monocytogenes at 4 °C can promote the selection of variants with enhanced cold and heat tolerance. Enhanced cold-tolerance (ECT) variants (n = 12) were successfully isolated from a strain with impaired cold growth abilities following 84 days of storage at 4 °C in brain heart infusion broth (BHIB). Whole genome sequencing, membrane fatty acid analysis, and stress tolerance profiling were performed on the parent strain and two ECT variants: one displaying regular-sized colonies and the other displaying small colonies when grown at 37 °C on BHI agar. Under cold stress conditions, the parent strain exhibited an impaired ability to produce branched-chain fatty acids which are known to be important for cold adaptation in L.monocytogenes. The ECT variants were able to overcome this limitation, a finding which is hypothesized to be associated with the identification of two independent single-nucleotide polymorphisms in genes encoding subunits of acetyl-coA carboxylase, an enzyme critical for fatty acid biosynthesis. While the ECT phenotype was not found to be associated with improved salt (BHIB + 6% NaCl, 25 °C), acid (BHIB pH 5, 25 °C) or desiccation (33% RH, 20 °C) tolerance, the small-colony variant exhibited significantly (p < 0.05) enhanced heat tolerance at 52 °C in buffered peptone water compared to the parent strain and the other variant. The results from this study demonstrate that the continuous use of refrigeration along the food-supply chain has the potential to select for L.monocytogenes variants with enhanced cold and heat tolerance, highlighting the impact that microbial intervention strategies can have on the evolution of bacterial strains and likewise, food safety.
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Affiliation(s)
- Patricia A Hingston
- Food, Nutrition and Health, The University of British Columbia, Vancouver, British Columbia, Canada
| | | | | | - Siyun Wang
- Food, Nutrition and Health, The University of British Columbia, Vancouver, British Columbia, Canada.
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24
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Fritsch L, Felten A, Palma F, Mariet JF, Radomski N, Mistou MY, Augustin JC, Guillier L. Insights from genome-wide approaches to identify variants associated to phenotypes at pan-genome scale: Application to L. monocytogenes' ability to grow in cold conditions. Int J Food Microbiol 2018; 291:181-188. [PMID: 30530095 DOI: 10.1016/j.ijfoodmicro.2018.11.028] [Citation(s) in RCA: 29] [Impact Index Per Article: 4.8] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/28/2018] [Revised: 10/09/2018] [Accepted: 11/28/2018] [Indexed: 10/27/2022]
Abstract
Intraspecific variability of the behavior of most foodborne pathogens is well described and taken into account in Quantitative Microbial Risk Assessment (QMRA), but factors (strain origin, serotype, …) explaining these differences are scarce or contradictory between studies. Nowadays, Whole Genome Sequencing (WGS) offers new opportunities to explain intraspecific variability of food pathogens, based on various recently published bioinformatics tools. The objective of this study is to get a better insight into different existing bioinformatics approaches to associate bacterial phenotype(s) and genotype(s). Therefore, a dataset of 51 L. monocytogenes strains, isolated from multiple sources (i.e. different food matrices and environments) and belonging to 17 clonal complexes (CC), were selected to represent large population diversity. Furthermore, the phenotypic variability of growth at low temperature was determined (i.e. qualitative phenotype), and the whole genomes of selected strains were sequenced. The almost exhaustive gene content, as well as the core genome SNPs based phylogenetic reconstruction, were derived from the whole sequenced genomes. A Bayesian inference method was applied to identify the branches on which the phenotype distribution evolves within sub-lineages. Two different Genome Wide Association Studies (i.e. gene- and SNP-based GWAS) were independently performed in order to link genetic mutations to the phenotype of interest. The genomic analyses presented in this study were successfully applied on the selected dataset. The Bayesian phylogenetic approach emphasized an association with "slow" growth ability at 2 °C of the lineage I, as well as CC9 of the lineage II. Moreover, both gene- and SNP-GWAS approaches displayed significant statistical associations with the tested phenotype. A list of 114 significantly associated genes, including genes already known to be involved in the cold adaption mechanism of L. monocytogenes and genes associated to mobile genetic elements (MGE), resulted from the gene-GWAS. On the other hand, a group of 184 highly associated SNPs were highlighted by SNP-GWAS, including SNPs detected in genes which were already likely involved in cold adaption; hypothetical proteins; and intergenic regions where for example promotors and regulators can be located. The successful application of combined bioinformatics approaches associating WGS-genotypes and specific phenotypes, could contribute to improve prediction of microbial behaviors in food. The implementation of this information in hazard identification and exposure assessment processes will open new possibilities to feed QMRA-models.
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Affiliation(s)
- Lena Fritsch
- French Agency for Food, Environmental and Occupational Health & Safety (Anses), Laboratory for Food Safety, Université Paris-Est, Maisons-Alfort F-94701, France
| | - Arnaud Felten
- French Agency for Food, Environmental and Occupational Health & Safety (Anses), Laboratory for Food Safety, Université Paris-Est, Maisons-Alfort F-94701, France
| | - Federica Palma
- French Agency for Food, Environmental and Occupational Health & Safety (Anses), Laboratory for Food Safety, Université Paris-Est, Maisons-Alfort F-94701, France
| | - Jean-François Mariet
- French Agency for Food, Environmental and Occupational Health & Safety (Anses), Laboratory for Food Safety, Université Paris-Est, Maisons-Alfort F-94701, France
| | - Nicolas Radomski
- French Agency for Food, Environmental and Occupational Health & Safety (Anses), Laboratory for Food Safety, Université Paris-Est, Maisons-Alfort F-94701, France
| | - Michel-Yves Mistou
- French Agency for Food, Environmental and Occupational Health & Safety (Anses), Laboratory for Food Safety, Université Paris-Est, Maisons-Alfort F-94701, France
| | - Jean-Christophe Augustin
- French Agency for Food, Environmental and Occupational Health & Safety (Anses), Laboratory for Food Safety, Université Paris-Est, Maisons-Alfort F-94701, France; Ecole Nationale Vétérinaire d'Alfort, Maisons-Alfort F-94704, France
| | - Laurent Guillier
- French Agency for Food, Environmental and Occupational Health & Safety (Anses), Laboratory for Food Safety, Université Paris-Est, Maisons-Alfort F-94701, France.
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25
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Li Y, Zhou D, Hu S, Xiao X, Yu Y, Li X. Transcriptomic analysis by RNA-seq of Escherichia coli O157:H7 response to prolonged cold stress. Lebensm Wiss Technol 2018. [DOI: 10.1016/j.lwt.2018.06.025] [Citation(s) in RCA: 14] [Impact Index Per Article: 2.3] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/30/2022]
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26
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Bergholz TM, Shah MK, Burall LS, Rakic-Martinez M, Datta AR. Genomic and phenotypic diversity of Listeria monocytogenes clonal complexes associated with human listeriosis. Appl Microbiol Biotechnol 2018; 102:3475-3485. [PMID: 29500754 DOI: 10.1007/s00253-018-8852-5] [Citation(s) in RCA: 49] [Impact Index Per Article: 8.2] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/12/2017] [Revised: 02/08/2018] [Accepted: 02/10/2018] [Indexed: 12/11/2022]
Abstract
Listeria monocytogenes is a pathogen of significant concern in many ready to eat foods due to its ability to survive and multiply even under significant environmental stresses. Listeriosis in humans is a concern, especially to high-risk populations such as those who are immunocompromised or pregnant, due to the high rates of morbidity and mortality. Whole genome sequencing has become a routine part of assessing L. monocytogenes isolated from patients, and the frequency of different genetic subtypes associated with listeriosis is now being reported. The recent abundance of genome sequences for L. monocytogenes has provided a wealth of information regarding the variation in core and accessory genomic elements. Newly described accessory genomic regions have been linked to greater virulence capabilities as well as greater resistance to environmental stressors such as sanitizers commonly used in food processing facilities. This review will provide a summary of our current understanding of stress response and virulence phenotypes of L. monocytogenes, within the context of the genetic diversity of the pathogen.
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Affiliation(s)
- Teresa M Bergholz
- Department of Microbiological Sciences, North Dakota State University, 130A Van Es, Fargo, ND, 58102, USA.
| | - Manoj K Shah
- Department of Microbiological Sciences, North Dakota State University, 130A Van Es, Fargo, ND, 58102, USA
| | - Laurel S Burall
- Center for Food Safety and Applied Nutrition, Food and Drug Administration, Laurel, MD, 20708, USA
| | - Mira Rakic-Martinez
- Center for Food Safety and Applied Nutrition, Food and Drug Administration, Laurel, MD, 20708, USA
| | - Atin R Datta
- Center for Food Safety and Applied Nutrition, Food and Drug Administration, Laurel, MD, 20708, USA
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