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Núño K, Jensen AS, O'Connor G, Houston TJ, Dikici E, Zingg JM, Deo S, Daunert S. Insights into Women's health: Exploring the vaginal microbiome, quorum sensing dynamics, and therapeutic potential of quorum sensing quenchers. Mol Aspects Med 2024; 100:101304. [PMID: 39255544 DOI: 10.1016/j.mam.2024.101304] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/29/2024] [Accepted: 07/28/2024] [Indexed: 09/12/2024]
Abstract
The vaginal microbiome is an important aspect of women's health that changes dynamically with various stages of the woman's life. Just like the gut microbiome, the vaginal microbiome can also be affected by pathologies that dramatically change the typical composition of native vaginal microorganisms. However, the mechanism as to how both vaginal endemic and gut endemic opportunistic microbes can express pathogenicity in vaginal polymicrobial biofilms is poorly understood. Quorum sensing is the cellular density-dependent bacterial and fungal communication process in which chemical signaling molecules, known as autoinducers, activate expression for genes responsible for virulence and pathogenicity, such as biofilm formation and virulence factor production. Quorum sensing inhibition, or quorum quenching, has been explored as a potential therapeutic route for both bacterial and fungal infections. By applying these quorum quenchers, one can reduce biofilm formation of opportunistic vaginal microbes and combine them with antibiotics for a synergistic effect. This review aims to display the relationship between the vaginal and gut microbiome, the role of quorum sensing in polymicrobial biofilm formation which cause pathology in the vaginal microbiome, and how quorum quenchers can be utilized to attenuate the severity of bacterial and fungal infections.
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Affiliation(s)
- Kevin Núño
- Department of Biochemistry and Molecular Biology, University of Miami, Miller School of Medicine, Miami, FL, 33136, USA
| | - Anne Sophie Jensen
- Department of Biochemistry and Molecular Biology, University of Miami, Miller School of Medicine, Miami, FL, 33136, USA
| | - Gregory O'Connor
- Department of Biochemistry and Molecular Biology, University of Miami, Miller School of Medicine, Miami, FL, 33136, USA; Dr. JT Macdonald Biomedical Nanotechnology Institute (BioNIUM), University of Miami, Miami, FL, 33136, USA
| | - Tiffani Janae Houston
- Department of Biochemistry and Molecular Biology, University of Miami, Miller School of Medicine, Miami, FL, 33136, USA; Department of Internal Medicine, University of Miami, Miller School of Medicine, Miami, FL, 33136, USA
| | - Emre Dikici
- Department of Biochemistry and Molecular Biology, University of Miami, Miller School of Medicine, Miami, FL, 33136, USA; Dr. JT Macdonald Biomedical Nanotechnology Institute (BioNIUM), University of Miami, Miami, FL, 33136, USA
| | - Jean Marc Zingg
- Department of Biochemistry and Molecular Biology, University of Miami, Miller School of Medicine, Miami, FL, 33136, USA; Dr. JT Macdonald Biomedical Nanotechnology Institute (BioNIUM), University of Miami, Miami, FL, 33136, USA
| | - Sapna Deo
- Department of Biochemistry and Molecular Biology, University of Miami, Miller School of Medicine, Miami, FL, 33136, USA; Dr. JT Macdonald Biomedical Nanotechnology Institute (BioNIUM), University of Miami, Miami, FL, 33136, USA
| | - Sylvia Daunert
- Department of Biochemistry and Molecular Biology, University of Miami, Miller School of Medicine, Miami, FL, 33136, USA; Dr. JT Macdonald Biomedical Nanotechnology Institute (BioNIUM), University of Miami, Miami, FL, 33136, USA; Sylvester Comprehensive Cancer Center, University of Miami, Miller School of Medicine, Miami, FL, 33136, USA.
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Lima LS, Müller TN, Ansiliero R, Schuster MB, Silva BL, Jaskulski IB, da Silva WP, Moroni LS. Biofilm formation by Listeria monocytogenes from the meat processing industry environment and the use of different combinations of detergents, sanitizers, and UV-A radiation to control this microorganism in planktonic and sessile forms. Braz J Microbiol 2024; 55:2483-2499. [PMID: 38767749 PMCID: PMC11405597 DOI: 10.1007/s42770-024-01361-7] [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: 12/06/2023] [Accepted: 04/29/2024] [Indexed: 05/22/2024] Open
Abstract
This study aimed to evaluate the ability of biofilm formation by L. monocytogenes from the meat processing industry environment, as well as the use of different combinations of detergents, sanitizers, and UV-A radiation in the control of this microorganism in the planktonic and sessile forms. Four L. monocytogenes isolates were evaluated and showed moderate ability to form biofilm, as well as carried genes related to biofilm production (agrB, agrD, prfA, actA, cheA, cheY, flaA, sigB), and genes related to tolerance to sanitizers (lde and qacH). The biofilm-forming isolates of L. monocytogenes were susceptible to quaternary ammonium compound (QAC) and peracetic acid (PA) in planktonic form, with minimum inhibitory concentrations of 125 and 75 ppm, respectively, for contact times of 10 and 5 min. These concentrations are lower than those recommended by the manufacturers, which are at least 200 and 300 ppm for QAC and PA, respectively. Biofilms of L. monocytogenes formed from a pool of isolates on stainless steel and polyurethane coupons were subjected to 14 treatments involving acid and enzymatic detergents, QAC and PA sanitizers, and UV-A radiation at varying concentrations and contact times. All treatments reduced L. monocytogenes counts in the biofilm, indicating that the tested detergents, sanitizers, and UV-A radiation exhibited antimicrobial activity against biofilms on both surface types. Notably, the biofilm formed on polyurethane showed greater tolerance to the evaluated compounds than the biofilm on stainless steel, likely due to the material's surface facilitating faster microbial colonization and the development of a more complex structure, as observed by scanning electron microscopy. Listeria monocytogenes isolates from the meat processing industry carry genes associated with biofilm production and can form biofilms on both stainless steel and polyurethane surfaces, which may contribute to their persistence within meat processing lines. Despite carrying sanitizer tolerance genes, QAC and PA effectively controlled these microorganisms in their planktonic form. However, combinations of detergent (AC and ENZ) with sanitizers (QAC and PA) at minimum concentrations of 125 ppm and 300 ppm, respectively, were the most effective.
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Affiliation(s)
- Larissa Siqueira Lima
- Departamento de Engenharia de Alimentos e Engenharia Química, Universidade do Estado de Santa Catarina, Pinhalzinho, SC, 89870-000, Brazil
| | - Taís Nunzio Müller
- Departamento de Engenharia de Alimentos e Engenharia Química, Universidade do Estado de Santa Catarina, Pinhalzinho, SC, 89870-000, Brazil
| | - Rafaela Ansiliero
- Departamento de Engenharia de Alimentos e Engenharia Química, Universidade do Estado de Santa Catarina, Pinhalzinho, SC, 89870-000, Brazil
| | - Marcia Bär Schuster
- Departamento de Engenharia de Alimentos e Engenharia Química, Universidade do Estado de Santa Catarina, Pinhalzinho, SC, 89870-000, Brazil
| | - Bruna Louise Silva
- Centro Multiusuário, Centro de Ciências Tecnológicas, Universidade do Estado de Santa Catarina, Joinville, SC, 89219-710, Brazil
| | - Itiane Barcellos Jaskulski
- Departamento de Ciência e Tecnologia Agroindustrial, Faculdade de Agronomia, Universidade Federal de Pelotas, Capão do Leão, RS, 96001-970, Brazil
- Centro de Desenvolvimento Tecnológico, Departamento de Biotecnologia, Universidade Federal de Pelotas, Pelotas, RS, 960110-610, Brazil
| | - Wladimir Padilha da Silva
- Departamento de Ciência e Tecnologia Agroindustrial, Faculdade de Agronomia, Universidade Federal de Pelotas, Capão do Leão, RS, 96001-970, Brazil
- Centro de Desenvolvimento Tecnológico, Departamento de Biotecnologia, Universidade Federal de Pelotas, Pelotas, RS, 960110-610, Brazil
| | - Liziane Schittler Moroni
- Departamento de Engenharia de Alimentos e Engenharia Química, Universidade do Estado de Santa Catarina, Pinhalzinho, SC, 89870-000, Brazil.
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3
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Bejder BS, Monda F, Gless BH, Bojer MS, Ingmer H, Olsen CA. A short-lived peptide signal regulates cell-to-cell communication in Listeria monocytogenes. Commun Biol 2024; 7:942. [PMID: 39097633 PMCID: PMC11297923 DOI: 10.1038/s42003-024-06623-6] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/12/2023] [Accepted: 07/23/2024] [Indexed: 08/05/2024] Open
Abstract
Quorum sensing (QS) is a mechanism that regulates group behavior in bacteria, and in Gram-positive bacteria, the communication molecules are often cyclic peptides, called autoinducing peptides (AIPs). We recently showed that pentameric thiolactone-containing AIPs from Listeria monocytogenes, and from other species, spontaneously undergo rapid rearrangement to homodetic cyclopeptides, which hampers our ability to study the activity of these short-lived compounds. Here, we developed chemically modified analogues that closely mimic the native AIPs while remaining structurally intact, by introducing N-methylation or thioester-to-thioether substitutions. The stabilized AIP analogues exhibit strong QS agonism in L. monocytogenes and allow structure-activity relationships to be studied. Our data provide evidence to suggest that the most potent AIP is in fact the very short-lived thiolactone-containing pentamer. Further, we find that the QS system in L. monocytogenes is more promiscuous with respect to the structural diversity allowed for agonistic AIPs than reported for the more extensively studied QS systems in Staphylococcus aureus and Staphylococcus epidermidis. The developed compounds will be important for uncovering the biology of L. monocytogenes, and the design principles should be broadly applicable to the study of AIPs in other species.
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Affiliation(s)
- Benjamin S Bejder
- Center for Biopharmaceuticals and Department of Drug Design and Pharmacology, Faculty of Health and Medical Sciences, University of Copenhagen, Copenhagen, Denmark
| | - Fabrizio Monda
- Center for Biopharmaceuticals and Department of Drug Design and Pharmacology, Faculty of Health and Medical Sciences, University of Copenhagen, Copenhagen, Denmark
- Nuevolution A/S, Amgen Research Copenhagen, Copenhagen, Denmark
| | - Bengt H Gless
- Center for Biopharmaceuticals and Department of Drug Design and Pharmacology, Faculty of Health and Medical Sciences, University of Copenhagen, Copenhagen, Denmark
- Yusuf Hamied Department of Chemistry, University of Cambridge, Cambridge, UK
| | - Martin S Bojer
- Department of Veterinary and Animal Sciences, Faculty of Health and Medical Sciences, University of Copenhagen, Frederiksberg C, Denmark
| | - Hanne Ingmer
- Department of Veterinary and Animal Sciences, Faculty of Health and Medical Sciences, University of Copenhagen, Frederiksberg C, Denmark
| | - Christian A Olsen
- Center for Biopharmaceuticals and Department of Drug Design and Pharmacology, Faculty of Health and Medical Sciences, University of Copenhagen, Copenhagen, Denmark.
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Yammine J, Doulgeraki AI, O'Byrne CP, Gharsallaoui A, Chihib NE, Karam L. The impact of different acidic conditions and food substrates on Listeria monocytogenes biofilms development and removal using nanoencapsulated carvacrol. Int J Food Microbiol 2024; 416:110676. [PMID: 38507974 DOI: 10.1016/j.ijfoodmicro.2024.110676] [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: 01/06/2024] [Revised: 02/16/2024] [Accepted: 03/09/2024] [Indexed: 03/22/2024]
Abstract
Listeria monocytogenes biofilms present a significant challenge in the food industry. This study explores the impact of different acidic conditions of culture media and food matrices on the development and removal of biofilms developed on stainless steel surfaces by wild-type (WT) L. monocytogenes strains as well as in two mutant derivatives, ΔsigB and ΔagrA, that have defects in the general stress response and quorum sensing, respectively. Additionally, the study investigates the efficacy of nanoencapsulated carvacrol as an antimicrobial against L. monocytogenes biofilms developed in Tryptic Soy Broth (TSB) culture media acidified to different pH conditions (3.5, 4.5, 5.5, 6.5), and in food substrates (apple juice, strained yogurt, vegetable soup, semi-skimmed milk) having the same pH levels. No biofilm formation was observed for all L. monocytogenes strains at pH levels of 3.5 and 4.5 in both culture media and food substrates. However, at pH 5.5 and 6.5, increased biofilm levels were observed in both the culture media and food substrates, with the WT strain showing significantly higher biofilm formation (3.04-6.05 log CFU cm-2) than the mutant strains (2.30-5.48 log CFU cm-2). For both applications, the nanoencapsulated carvacrol demonstrated more potent antimicrobial activity against biofilms developed at pH 5.5 with 2.23 to 3.61 log reductions, compared to 1.58-2.95 log reductions at pH 6.5, with mutants being more vulnerable in acidic environments. In food substrates, nanoencapsulated carvacrol induced lower log reductions (1.58-2.90) than the ones in TSB (2.02-3.61). These findings provide valuable insights into the impact of different acidic conditions on the development of L. monocytogenes biofilms on stainless steel surfaces and the potential application of nanoencapsulated carvacrol as a biofilm control agent in food processing environments.
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Affiliation(s)
- Jina Yammine
- Univ Lille, CNRS, INRAE, Centrale Lille, UMR 8207 - UMET - Unité Matériaux et Transformations, Lille, France
| | - Agapi I Doulgeraki
- Laboratory of Food Microbiology and Hygiene, Department of Food Science & Technology, Faculty of Agriculture, Aristotle University of Thessaloniki, 54124 Thessaloniki, Greece
| | - Conor P O'Byrne
- Bacterial Stress Response Group, Microbiology, School of Biological & Chemical Sciences, University of Galway, Galway H91 TK33, Ireland
| | - Adem Gharsallaoui
- Univ Lyon, Université Claude Bernard Lyon 1, CNRS, LAGEPP UMR 5007, Villeurbanne, France
| | - Nour-Eddine Chihib
- Univ Lille, CNRS, INRAE, Centrale Lille, UMR 8207 - UMET - Unité Matériaux et Transformations, Lille, France
| | - Layal Karam
- Human Nutrition Department, College of Health Sciences, QU Health, Qatar University, Doha, Qatar.
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5
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West KHJ, Ma SV, Pensinger DA, Tucholski T, Tiambeng TN, Eisenbraun EL, Yehuda A, Hayouka Z, Ge Y, Sauer JD, Blackwell HE. Characterization of an Autoinducing Peptide Signal Reveals Highly Efficacious Synthetic Inhibitors and Activators of Quorum Sensing and Biofilm Formation in Listeria monocytogenes. Biochemistry 2023; 62:2878-2892. [PMID: 37699554 PMCID: PMC10676741 DOI: 10.1021/acs.biochem.3c00373] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 09/14/2023]
Abstract
Bacteria can use chemical signals to assess their local population density in a process called quorum sensing (QS). Many of these bacteria are common pathogens, including Gram-positive bacteria that utilize agr QS systems regulated by macrocyclic autoinducing peptide (AIP) signals. Listeria monocytogenes, an important foodborne pathogen, uses an agr system to regulate a variety of virulence factors and biofilm formation, yet little is known about the specific roles of agr in Listeria infection and its persistence in various environments. Herein, we report synthetic peptide tools that will enable the study of QS in Listeria. We identified a 6-mer AIP signal in L. monocytogenes supernatants and selected it as a scaffold around which a collection of non-native AIP mimics was designed and synthesized. These peptides were evaluated in cell-based agr reporter assays to generate structure-activity relationships for AIP-based agonism and antagonism in L. monocytogenes. We discovered synthetic agonists with increased potency relative to native AIP and a synthetic antagonist capable of reducing agr activity to basal levels. Notably, the latter peptide was able to reduce biofilm formation by over 90%, a first for a synthetic QS modulator in wild-type L. monocytogenes. The lead agr agonist and antagonist in L. monocytogenes were also capable of antagonizing agr signaling in the related pathogen Staphylococcus aureus, further extending their utility and suggesting different mechanisms of agr activation in these two pathogens. This study represents an important first step in the application of chemical methods to modulate QS and concomitant virulence outcomes in L. monocytogenes.
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Affiliation(s)
- Korbin H J West
- Department of Chemistry, University of Wisconsin-Madison, 1101 University Ave., Madison, Wisconsin 53706, United States
| | - Stella V Ma
- Department of Chemistry, University of Wisconsin-Madison, 1101 University Ave., Madison, Wisconsin 53706, United States
| | - Daniel A Pensinger
- Department of Medical Microbiology and Immunology, University of Wisconsin-Madison, 1550 Linden Dr., Madison, Wisconsin 53706, United States
| | - Trisha Tucholski
- Department of Chemistry, University of Wisconsin-Madison, 1101 University Ave., Madison, Wisconsin 53706, United States
| | - Timothy N Tiambeng
- Department of Chemistry, University of Wisconsin-Madison, 1101 University Ave., Madison, Wisconsin 53706, United States
| | - Emma L Eisenbraun
- Department of Chemistry, University of Wisconsin-Madison, 1101 University Ave., Madison, Wisconsin 53706, United States
| | - Avishag Yehuda
- Institute of Biochemistry, Food Science and Nutrition, Robert H. Smith Faculty of Agriculture, Food and Environment, The Hebrew University of Jerusalem, Rehovot 7610001, Israel
| | - Zvi Hayouka
- Institute of Biochemistry, Food Science and Nutrition, Robert H. Smith Faculty of Agriculture, Food and Environment, The Hebrew University of Jerusalem, Rehovot 7610001, Israel
| | - Ying Ge
- Department of Chemistry, University of Wisconsin-Madison, 1101 University Ave., Madison, Wisconsin 53706, United States
- Department of Cell and Regenerative Biology, University of Wisconsin-Madison, Wisconsin Institute for Medical Research, 1111 Highland Ave., Madison, Wisconsin 53705, United States
| | - John-Demian Sauer
- Department of Medical Microbiology and Immunology, University of Wisconsin-Madison, 1550 Linden Dr., Madison, Wisconsin 53706, United States
| | - Helen E Blackwell
- Department of Chemistry, University of Wisconsin-Madison, 1101 University Ave., Madison, Wisconsin 53706, United States
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Finn L, Onyeaka H, O’Neill S. Listeria monocytogenes Biofilms in Food-Associated Environments: A Persistent Enigma. Foods 2023; 12:3339. [PMID: 37761048 PMCID: PMC10529182 DOI: 10.3390/foods12183339] [Citation(s) in RCA: 2] [Impact Index Per Article: 2.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/03/2023] [Revised: 08/31/2023] [Accepted: 09/01/2023] [Indexed: 09/29/2023] Open
Abstract
Listeria monocytogenes (LM) is a bacterial pathogen responsible for listeriosis, a foodborne illness associated with high rates of mortality (20-30%) and hospitalisation. It is particularly dangerous among vulnerable groups, such as newborns, pregnant women and the elderly. The persistence of this organism in food-associated environments for months to years has been linked to several devastating listeriosis outbreaks. It may also result in significant costs to food businesses and economies. Currently, the mechanisms that facilitate LM persistence are poorly understood. Unravelling the enigma of what drives listerial persistence will be critical for developing more targeted control and prevention strategies. One prevailing hypothesis is that persistent strains exhibit stronger biofilm production on abiotic surfaces in food-associated environments. This review aims to (i) provide a comprehensive overview of the research on the relationship between listerial persistence and biofilm formation from phenotypic and whole-genome sequencing (WGS) studies; (ii) to highlight the ongoing challenges in determining the role biofilm development plays in persistence, if any; and (iii) to propose future research directions for overcoming these challenges.
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Affiliation(s)
| | - Helen Onyeaka
- School of Chemical Engineering, University of Birmingham, Birmingham B15 2TT, UK
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7
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Quendera AP, Pinto SN, Pobre V, Antunes W, Bonifácio VDB, Arraiano CM, Andrade JM. The ribonuclease PNPase is a key regulator of biofilm formation in Listeria monocytogenes and affects invasion of host cells. NPJ Biofilms Microbiomes 2023; 9:34. [PMID: 37286543 PMCID: PMC10247797 DOI: 10.1038/s41522-023-00397-1] [Citation(s) in RCA: 3] [Impact Index Per Article: 3.0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/25/2022] [Accepted: 05/18/2023] [Indexed: 06/09/2023] Open
Abstract
Biofilms provide an environment that protects microorganisms from external stresses such as nutrient deprivation, antibiotic treatments, and immune defences, thereby creating favorable conditions for bacterial survival and pathogenesis. Here we show that the RNA-binding protein and ribonuclease polynucleotide phosphorylase (PNPase) is a positive regulator of biofilm formation in the human pathogen Listeria monocytogenes, a major responsible for food contamination in food-processing environments. The PNPase mutant strain produces less biofilm biomass and exhibits an altered biofilm morphology that is more susceptible to antibiotic treatment. Through biochemical assays and microscopical analysis, we demonstrate that PNPase is a previously unrecognized regulator of the composition of the biofilm extracellular matrix, greatly affecting the levels of proteins, extracellular DNA, and sugars. Noteworthy, we have adapted the use of the fluorescent complex ruthenium red-phenanthroline for the detection of polysaccharides in Listeria biofilms. Transcriptomic analysis of wild-type and PNPase mutant biofilms reveals that PNPase impacts many regulatory pathways associated with biofilm formation, particularly by affecting the expression of genes involved in the metabolism of carbohydrates (e.g., lmo0096 and lmo0783, encoding PTS components), of amino acids (e.g., lmo1984 and lmo2006, encoding biosynthetic enzymes) and in the Agr quorum sensing-like system (lmo0048-49). Moreover, we show that PNPase affects mRNA levels of the master regulator of virulence PrfA and PrfA-regulated genes, and these results could help to explain the reduced bacterial internalization in human cells of the ΔpnpA mutant. Overall, this work demonstrates that PNPase is an important post-transcriptional regulator for virulence and adaptation to the biofilm lifestyle of Gram-positive bacteria and highlights the expanding role of ribonucleases as critical players in pathogenicity.
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Affiliation(s)
- Ana Patrícia Quendera
- Instituto de Tecnologia Química e Biológica António Xavier, Universidade Nova de Lisboa (ITQB NOVA), Avenida da República, 2780-901, Oeiras, Portugal
| | - Sandra Nunes Pinto
- Institute for Bioengineering and Biosciences (IBB) and Associate Laboratory-Institute for Health and Bioeconomy (i4HB), Instituto Superior Técnico, Universidade de Lisboa, Av. Rovisco Pais, 1049-001, Lisboa, Portugal
| | - Vânia Pobre
- Instituto de Tecnologia Química e Biológica António Xavier, Universidade Nova de Lisboa (ITQB NOVA), Avenida da República, 2780-901, Oeiras, Portugal
| | - Wilson Antunes
- Laboratório de Imagem, Nanomorfologia e Espectroscopia de Raios-X (Linx) da Unidade Militar Laboratorial de Defesa Biológica e Química (UMLDBQ), Instituto Universitário Militar, Centro de Investigação, Inovação e Desenvolvimento da Academia Militar, Av. Dr Alfredo Bensaúde, 1100-471, Lisboa, Portugal
| | - Vasco D B Bonifácio
- Institute for Bioengineering and Biosciences (IBB) and Associate Laboratory-Institute for Health and Bioeconomy (i4HB), Instituto Superior Técnico, Universidade de Lisboa, Av. Rovisco Pais, 1049-001, Lisboa, Portugal
- Bioengineering Department, Instituto Superior Técnico, Universidade de Lisboa, Av. Rovisco Pais, 1049-001, Lisboa, Portugal
| | - Cecília Maria Arraiano
- Instituto de Tecnologia Química e Biológica António Xavier, Universidade Nova de Lisboa (ITQB NOVA), Avenida da República, 2780-901, Oeiras, Portugal
| | - José Marques Andrade
- Instituto de Tecnologia Química e Biológica António Xavier, Universidade Nova de Lisboa (ITQB NOVA), Avenida da República, 2780-901, Oeiras, Portugal.
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The small non-coding RNA rli106 contributes to the environmental adaptation and pathogenicity of Listeria monocytogenes. J Vet Res 2023; 67:67-77. [PMID: 37008770 PMCID: PMC10062041 DOI: 10.2478/jvetres-2023-0013] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/01/2022] [Accepted: 03/03/2023] [Indexed: 03/18/2023] Open
Abstract
Abstract
Introduction
Listeria monocytogenes (LM) is an important food-borne pathogen, and the risk of its ingestion is a serious public health issue. The better its environmental adaptation mechanisms and pathogenicity are understood, the better the risk it poses can be countered. The regulatory role of the small non-coding RNA (sRNA) rli106 in the environmental adaptation and pathogenicity of LM is still unclear and this study investigated that role through its biological function.
Material and Methods
An LM-Δrli106 gene deletion strain and an LM-Δrli106/rli106 gene complementation strain were constructed using the homologous recombination technique. Then, the adaptation of these strains to temperature, alkalinity, acidity, salinity, ethanol and oxidative stressors, their biofilm-forming ability and their pathogenicity in mice were investigated to show the regulatory roles of sRNA rli106 in LM. The target gene of rli106 was also predicted, and the interaction between it and rli106 was verified by a two-plasmid co-expressing system based on
E.coli
and Western blot analysis.
Results
The adaptation of LM-Δrli106 to environmental stressors of pH 9, 5% NaCl and 8% NaCl, 3.8% ethanol and 5 mM H2O2 was significantly reduced when compared to the parental (LM EGD-e) and complementation strains. Also, the biofilm formation, cell adhesion, invasion, intracellular proliferation and pathogenicity of LM-Δrli106 in mice were significantly reduced. The results of two-plasmid co-expression and Western blot showed that rli106 can interact with the mRNA of the predicted DegU target gene.
Conclusion
The sRNA rli106 may positively regulate the expression of the DegU gene in LM. This study sheds light on its regulatory roles in environmental adaptation and pathogenicity, providing new insights into the molecular mechanism of sRNA mediation in LM .
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Molecular typing and genome sequencing allow the identification of persistent Listeria monocytogenes strains and the tracking of the contamination source in food environments. Int J Food Microbiol 2023; 386:110025. [PMID: 36436413 DOI: 10.1016/j.ijfoodmicro.2022.110025] [Citation(s) in RCA: 9] [Impact Index Per Article: 9.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/02/2022] [Revised: 11/08/2022] [Accepted: 11/16/2022] [Indexed: 11/23/2022]
Abstract
The presence of Listeria monocytogenes (Lm) in the food processing environment (facilities and products) is a challenging problem in food safety management. Lm is one of the main causes of mortality in foodborne infections, and the trend is continuously increasing. In this study, a collection of 323 Lm strain isolates recovered from food matrices and food industry environments (surfaces and equipment) over four years from 80 food processing facilities was screened using a restriction site-associated tag sequencing (2b-RAD) typing approach developed for Lm. Thirty-six different restriction site-associated DNA (RAD) types (RTs) were identified, most of which correspond to lineage II. RT1, the most represented genotype in our collection and already reported as one of the most prevalent genotypes in the food environment, was significantly associated with meat processing facilities. The sequencing of the genomes of strains belonging to the same RT and isolated in the same facility in different years revealed several clusters of persistence. The definition of the persistent strains (PSs) allowed the identification of the potential source of contamination in the incoming raw meat that is introduced in the facility to be processed. The slaughterhouses, which, according to the European Union (EU) regulation, are not inspected for the presence of Lm could be hotspots for the persistence of Lm PSs.
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10
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Ashrafudoulla M, Ulrich MSI, Toushik SH, Nahar S, Roy PK, Mizan FR, Park SH, Ha SD. Challenges and opportunities of non-conventional technologies concerning food safety. WORLD POULTRY SCI J 2023. [DOI: 10.1080/00439339.2023.2163044] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/26/2023]
Affiliation(s)
- Md. Ashrafudoulla
- Department of Food Science and Technology, Chung-Ang University, Anseong-Si, Republic of Korea
| | - Mevo S. I. Ulrich
- Department of Food Science and Technology, Chung-Ang University, Anseong-Si, Republic of Korea
| | | | - Shamsun Nahar
- Department of Food Science and Technology, Chung-Ang University, Anseong-Si, Republic of Korea
| | - Pantu Kumar Roy
- Department of Seafood Science and Technology, Gyeongsang National University, Tongyeong, Republic of Korea
| | - Furkanur Rahaman Mizan
- Department of Food Science and Technology, Chung-Ang University, Anseong-Si, Republic of Korea
| | - Si Hong Park
- Food Science and Technology, Oregon State University, Corvallis, Oregon, USA
| | - Sang-Do Ha
- Department of Food Science and Technology, Chung-Ang University, Anseong-Si, Republic of Korea
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11
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Baig MMFA, Fatima A, Gao X, Farid A, Ajmal Khan M, Zia AW, Wu H. Disrupting biofilm and eradicating bacteria by Ag-Fe 3O 4@MoS 2 MNPs nanocomposite carrying enzyme and antibiotics. J Control Release 2022; 352:98-120. [PMID: 36243235 DOI: 10.1016/j.jconrel.2022.10.009] [Citation(s) in RCA: 5] [Impact Index Per Article: 2.5] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/31/2022] [Revised: 09/07/2022] [Accepted: 10/04/2022] [Indexed: 11/08/2022]
Abstract
In this study, novel multilayered magnetic nanoparticles (ML-MNPs) loaded with DNase and/or vancomycin (Vanc) were fabricated for eliminating multispecies biofilms. Iron-oxide MNPs (IO-core) (500-800 nm) were synthesized via co-precipitation; further, the IO-core was coated with heavy-metal-based layers (Ag and MoS2 NPs) using solvent evaporation. DNase and Vanc were loaded onto the outermost layer of the ML-MNP formed by nanoporous MoS2 NPs through physical deposition and adsorption. The biofilms of S. mutans or E. faecalis (or both) were formed in a brain-heart-infusion broth (BHI) for 3 days, followed by treatment with ML-MNPs for 24 h. The results revealed that coatings of Ag (200 nm) and ultrasmall MoS2 (20 nm) were assembled as outer layers of ML-MNPs successfully, and they formed Ag-Fe3O4@MoS2 MNPs (3-5 μm). The DNase-Vanc-loaded MNPs caused nanochannels digging and resulted in the enhanced penetration of MNPs towards the bottom layers of biofilm, which resulted in a decrease in the thickness of the 72-h biofilm from 48 to 58 μm to 0-4 μm. The sustained release of Vanc caused a synergistic bacterial killing up to 96%-100%. The heavy-metal-based layers of MNPs act as nanozymes to interfere with bacterial metabolism and proliferation, which adversely affects biofilm integrity. Further, loading DNase/Vanc onto the nanoporous-MoS2-layer of ML-MNPs promoted nanochannel creation through the biofilm. Therefore, DNase-and Vanc-loaded ML-MNPs exhibited potent effects on biofilm disruption and bacterial killing.
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Affiliation(s)
- Mirza Muhammad Faran Ashraf Baig
- Department of Chemistry and the Hong Kong Branch of Chinese National Engineering Research Centre for Tissue Restoration, The Hong Kong University of Science and Technology, Clear Water Bay, Hong Kong SAR, China.
| | - Arshia Fatima
- Department of Chemistry and the Hong Kong Branch of Chinese National Engineering Research Centre for Tissue Restoration, The Hong Kong University of Science and Technology, Clear Water Bay, Hong Kong SAR, China
| | - Xiuli Gao
- Microbiology and Biochemical Pharmaceutical Engineering Research Center of Guizhou Provincial Department of Education, State Key Laboratory of Functions and Applications of Medicinal Plants, School of Pharmacy, Guizhou Medical University, Guiyang 550025, China.
| | - Awais Farid
- Division of Environment and Sustainability, The Hong Kong University of Science and Technology, Clear Water Bay, Hong Kong, China
| | - Muhammad Ajmal Khan
- Division of Life Science, The Hong Kong University of Science and Technology, Clear Water Bay, Hong Kong, China
| | - Abdul Wasy Zia
- Department of Mechanical and Construction Engineering, Marie Curie Research Unit, Northumbria University, Newcastle, United Kingdom
| | - Hongkai Wu
- Department of Chemistry and the Hong Kong Branch of Chinese National Engineering Research Centre for Tissue Restoration, The Hong Kong University of Science and Technology, Clear Water Bay, Hong Kong SAR, China; Department of Chemical and Biological Engineering, Division of Biomedical Engineering, School of Engineering, The Hong Kong University of Science and Technology, Clear Water Bay, Hong Kong, China.
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12
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Fan Q, Zuo J, Wang H, Grenier D, Yi L, Wang Y. Contribution of quorum sensing to virulence and antibiotic resistance in zoonotic bacteria. Biotechnol Adv 2022; 59:107965. [PMID: 35487393 DOI: 10.1016/j.biotechadv.2022.107965] [Citation(s) in RCA: 28] [Impact Index Per Article: 14.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/28/2022] [Revised: 04/15/2022] [Accepted: 04/21/2022] [Indexed: 11/02/2022]
Abstract
Quorum sensing (QS), which is a key part of cell/cell communication, is widely distributed in microorganisms, especially in bacteria. Bacteria can produce and detect the presence of QS signal molecule, perceive the composition and density of microorganisms in their complex habitat, and then dynamically regulate their own gene expression to adapt to their environment. Among the many traits controlled by QS in pathogenic bacteria is the expression of virulence factors and antibiotic resistance. Many pathogenic bacteria rely on QS to govern the production of virulence factors and express drug-resistance, especially in zoonotic bacteria. The threat of antibiotic resistant zoonotic bacteria has called for alternative antimicrobial strategies that would mitigate the increase of classical resistance mechanism. Targeting QS has proven to be a promising alternative to conventional antibiotic for controlling infections. Here we review the QS systems in common zoonotic pathogenic bacteria and outline how QS may control the virulence and antibiotic resistance of zoonotic bacteria.
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Affiliation(s)
- Qingying Fan
- College of Animal Science and Technology, Henan University of Science and Technology, Luoyang, China; Key Laboratory of Molecular Pathogen and Immunology of Animal of Luoyang, Luoyang, China
| | - Jing Zuo
- College of Animal Science and Technology, Henan University of Science and Technology, Luoyang, China; Key Laboratory of Molecular Pathogen and Immunology of Animal of Luoyang, Luoyang, China
| | - Haikun Wang
- College of Animal Science and Technology, Henan University of Science and Technology, Luoyang, China; Key Laboratory of Molecular Pathogen and Immunology of Animal of Luoyang, Luoyang, China
| | - Daniel Grenier
- Groupe de Recherche en Écologie Buccale (GREB), Faculté de Médecine Dentaire, Université Laval, Quebec City, Canada
| | - Li Yi
- Key Laboratory of Molecular Pathogen and Immunology of Animal of Luoyang, Luoyang, China; College of Life Science, Luoyang Normal University, Luoyang, China.
| | - Yang Wang
- College of Animal Science and Technology, Henan University of Science and Technology, Luoyang, China; Key Laboratory of Molecular Pathogen and Immunology of Animal of Luoyang, Luoyang, China.
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13
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Marmion M, Macori G, Whyte P, Scannell AGM. Stress response modulation: the key to survival of pathogenic and spoilage bacteria during poultry processing. MICROBIOLOGY (READING, ENGLAND) 2022; 168. [PMID: 35451951 DOI: 10.1099/mic.0.001184] [Citation(s) in RCA: 2] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 11/18/2022]
Abstract
The control of bacterial contaminants on meat is a key area of interest in the food industry. Bacteria are exposed to a variety of stresses during broiler processing which challenge bacterial structures and metabolic pathways causing death or sublethal injury. To counter these stresses, bacteria possess robust response systems that can induce shifts in the transcriptome and proteome to enable survival. Effective adaptive responses, such as biofilm formation, shock protein production and metabolic flexibility, require rapid induction and implementation at a cellular and community level to facilitate bacterial survival in adverse conditions. This review aims to provide an overview of the scientific literature pertaining to the regulation of complex adaptive processes used by bacteria to survive the processing environment, with particular focus on species that impact the quality and safety of poultry products like Campylobacter spp., Salmonella enterica and Pseudomonas spp.
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Affiliation(s)
- Maitiú Marmion
- UCD School of Agriculture and Food Science, Belfield, Dublin 4, D04V4W8, Ireland.,UCD Centre for Food Safety, University College Dublin, Belfield, Dublin 4, D04V4W8, Ireland
| | - Guerrino Macori
- UCD School of Agriculture and Food Science, Belfield, Dublin 4, D04V4W8, Ireland.,UCD Centre for Food Safety, University College Dublin, Belfield, Dublin 4, D04V4W8, Ireland
| | - Paul Whyte
- UCD School of Veterinary Medicine, Belfield, Dublin 4, D04V4W8, Ireland
| | - Amalia G M Scannell
- UCD School of Agriculture and Food Science, Belfield, Dublin 4, D04V4W8, Ireland.,UCD Centre for Food Safety, University College Dublin, Belfield, Dublin 4, D04V4W8, Ireland.,UCD Institute of Food and Health, Belfield, Dublin 4, D04V4W8, Ireland
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14
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Marmion M, Macori G, Ferone M, Whyte P, Scannell A. Survive and thrive: Control mechanisms that facilitate bacterial adaptation to survive manufacturing-related stress. Int J Food Microbiol 2022; 368:109612. [DOI: 10.1016/j.ijfoodmicro.2022.109612] [Citation(s) in RCA: 2] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/02/2021] [Revised: 02/21/2022] [Accepted: 03/02/2022] [Indexed: 10/18/2022]
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15
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Mgomi FC, Yuan L, Chen CW, Zhang YS, Yang ZQ. Bacteriophages: A weapon against mixed-species biofilms in the food processing environment. J Appl Microbiol 2021; 133:2107-2121. [PMID: 34932868 DOI: 10.1111/jam.15421] [Citation(s) in RCA: 8] [Impact Index Per Article: 2.7] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/04/2021] [Revised: 11/18/2021] [Accepted: 12/17/2021] [Indexed: 11/28/2022]
Abstract
Mixed-species biofilms represent the most frequent actual lifestyles of microorganisms in food processing environments, and they are usually more resistant to control methods than single-species biofilms. The persistence of biofilms formed by foodborne pathogens is believed to cause serious human diseases. These challenges have encouraged researchers to search for novel, natural methods that are more effective towards mixed-species biofilms. Recently, the use of bacteriophages to control mixed-species biofilms have grown significantly in the food industry as an alternative to conventional methods. This review highlights a comprehensive introduction of mixed-species biofilms formed by foodborne pathogens and their enhanced resistance to anti-biofilm removal strategies. Additionally, several methods for controlling mixed-species biofilms briefly focused on applying bacteriophages in the food industry have also been discussed. This article concludes by suggesting that using bacteriophage, combined with other 'green' methods, could effectively control mixed-species biofilms in the food industry.
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Affiliation(s)
- Fedrick C Mgomi
- College of Food Science and Engineering, Yangzhou University, Yangzhou, Jiangsu, 225127, PR China
| | - Lei Yuan
- College of Food Science and Engineering, Yangzhou University, Yangzhou, Jiangsu, 225127, PR China
| | - Cao-Wei Chen
- College of Food Science and Engineering, Yangzhou University, Yangzhou, Jiangsu, 225127, PR China
| | - Yuan-Song Zhang
- College of Food Science and Engineering, Yangzhou University, Yangzhou, Jiangsu, 225127, PR China
| | - Zhen-Quan Yang
- College of Food Science and Engineering, Yangzhou University, Yangzhou, Jiangsu, 225127, PR China
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16
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Janež N, Škrlj B, Sterniša M, Klančnik A, Sabotič J. The role of the Listeria monocytogenes surfactome in biofilm formation. Microb Biotechnol 2021; 14:1269-1281. [PMID: 34106516 PMCID: PMC8313260 DOI: 10.1111/1751-7915.13847] [Citation(s) in RCA: 10] [Impact Index Per Article: 3.3] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/16/2021] [Revised: 05/12/2021] [Accepted: 05/17/2021] [Indexed: 12/11/2022] Open
Abstract
Listeria monocytogenes is a highly pathogenic foodborne bacterium that is ubiquitous in the natural environment and capable of forming persistent biofilms in food processing environments. This species has a rich repertoire of surface structures that enable it to survive, adapt and persist in various environments and promote biofilm formation. We review current understanding and advances on how L. monocytogenes organizes its surface for biofilm formation on surfaces associated with food processing settings, because they may be an important target for development of novel antibiofilm compounds. A synthesis of the current knowledge on the role of Listeria surfactome, comprising peptidoglycan, teichoic acids and cell wall proteins, during biofilm formation on abiotic surfaces is provided. We consider indications gained from genome-wide studies and discuss surfactome structures with established mechanistic aspects in biofilm formation. Additionally, we look at the analogies to the species L. innocua, which is closely related to L. monocytogenes and often used as its model (surrogate) organism.
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Affiliation(s)
- Nika Janež
- Department of BiotechnologyJožef Stefan InstituteLjubljanaSlovenia
| | - Blaž Škrlj
- Department of Knowledge TechnologiesJožef Stefan InstituteLjubljanaSlovenia
- Jožef Stefan International Postgraduate SchoolLjubljanaSlovenia
| | - Meta Sterniša
- Department of Food Science and TechnologyBiotechnical FacultyUniversity of LjubljanaLjubljanaSlovenia
| | - Anja Klančnik
- Department of Food Science and TechnologyBiotechnical FacultyUniversity of LjubljanaLjubljanaSlovenia
| | - Jerica Sabotič
- Department of BiotechnologyJožef Stefan InstituteLjubljanaSlovenia
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17
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Factors contributing to Listeria monocytogenes transmission and impact on food safety. Curr Opin Food Sci 2020. [DOI: 10.1016/j.cofs.2020.09.009] [Citation(s) in RCA: 9] [Impact Index Per Article: 2.3] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/19/2022]
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18
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Rattanaphan P, Mittraparp-Arthorn P, Srinoun K, Vuddhakul V, Tansila N. Indole signaling decreases biofilm formation and related virulence of Listeria monocytogenes. FEMS Microbiol Lett 2020; 367:5870657. [PMID: 32658271 DOI: 10.1093/femsle/fnaa116] [Citation(s) in RCA: 21] [Impact Index Per Article: 5.3] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/23/2020] [Accepted: 07/10/2020] [Indexed: 12/17/2022] Open
Abstract
Bacterial communication system known as quorum sensing (QS) is a pivotal system for bacterial survival, adaptation and pathogenesis. Members in the multicellular community may synthesize or acquire a signaling molecule in order to elicit downstream cellular processes. Roles of indole and derivatives, a new class of quorum-sensing signal molecules, in various bacterial physiologies and virulence have been reported recently. Indole is normally found in mammal gastrointestinal tract as a metabolite of tryptophan metabolism by microbiota. Therefore, interspecies connection via indole signaling among commensal bacteria and enteric pathogens could be anticipated. Effects of indole exposure on the virulence of Listeria monocytogenes were investigated by phenotypic and molecular approaches. Results demonstrated that synthetic indole and indole-rich conditioned medium significantly diminished biofilm formation and related virulence of L. monocytogenes including motility, cell aggregation and exopolysaccharide production. Transcript levels of virulence-associated (pssE, dltA, flaA, fliI, motB, agrA and hly) and regulatory genes (codY, sigB, prfA and gmaR) were substantially downregulated in indole-treated cells. Only mogR gene encoding for a repressor of motility genes was upregulated after indole exposure. Our findings raise the possibility that L. monocytogenes may acquire indole signaling from gut microbiota for resource-effective adaptation upon transition to new environment.
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Affiliation(s)
- Paramaporn Rattanaphan
- Department of Microbiology, Faculty of Science, Prince of Songkla University, Hat Yai, Songkhla 90110, Thailand
| | - Pimonsri Mittraparp-Arthorn
- Department of Microbiology, Faculty of Science, Prince of Songkla University, Hat Yai, Songkhla 90110, Thailand
| | - Kanitta Srinoun
- Faculty of Medical Technology, Prince of Songkla University, Hat Yai, Songkhla 90110, Thailand
| | - Varaporn Vuddhakul
- Department of Microbiology, Faculty of Science, Prince of Songkla University, Hat Yai, Songkhla 90110, Thailand
| | - Natta Tansila
- Faculty of Medical Technology, Prince of Songkla University, Hat Yai, Songkhla 90110, Thailand
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19
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Zetzmann M, Bucur FI, Crauwels P, Borda D, Nicolau AI, Grigore-Gurgu L, Seibold GM, Riedel CU. Characterization of the biofilm phenotype of a Listeria monocytogenes mutant deficient in agr peptide sensing. Microbiologyopen 2019; 8:e00826. [PMID: 30843349 PMCID: PMC6741131 DOI: 10.1002/mbo3.826] [Citation(s) in RCA: 10] [Impact Index Per Article: 2.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/06/2018] [Revised: 02/01/2019] [Accepted: 02/04/2019] [Indexed: 12/12/2022] Open
Abstract
Listeria monocytogenes is a food‐borne human pathogen and a serious concern in food production and preservation. Previous studies have shown that biofilm formation of L. monocytogenes and presence of extracellular DNA (eDNA) in the biofilm matrix varies with environmental conditions and may involve agr peptide sensing. Experiments in normal and diluted (hypoosmotic) complex media at different temperatures revealed reduced biofilm formation of L. monocytogenes EGD‐e ΔagrD, a mutant deficient in agr peptide sensing, specifically in diluted Brain Heart Infusion at 25°C. This defect was not related to reduced sensitivity to DNase treatment suggesting sufficient levels of eDNA. Re‐analysis of a previously published transcriptional profiling indicated that a total of 132 stress‐related genes, that is 78.6% of the SigB‐dependent stress regulon, are differentially expressed in the ΔagrD mutant. Additionally, a number of genes involved in flagellar motility and a large number of other surface proteins including internalins, peptidoglycan binding and cell wall modifying proteins showed agr‐dependent gene expression. However, survival of the ΔagrD mutant in hypoosmotic conditions or following exposure to high hydrostatic pressure was comparable to the wild type. Also, flagellar motility and surface hydrophobicity were not affected. However, the ΔagrD mutant displayed a significantly reduced viability upon challenge with lysozyme. These results suggest that the biofilm phenotype of the ΔagrD mutant is not a consequence of reduced resistance to hypoosmotic or high pressure stress, motility or surface hydrophobicity. Instead, agr peptide sensing seems to be required for proper regulation of biosynthesis, structure and function of the cell envelope, adhesion to the substratum, and/or interaction of bacteria within a biofilm.
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Affiliation(s)
- Marion Zetzmann
- Institute of Microbiology and Biotechnology, University of Ulm, Ulm, Germany
| | - Florentina Ionela Bucur
- Faculty of Food Science and Engineering, Dunarea de Jos University of Galati, Galati, Romania
| | - Peter Crauwels
- Institute of Microbiology and Biotechnology, University of Ulm, Ulm, Germany
| | - Daniela Borda
- Faculty of Food Science and Engineering, Dunarea de Jos University of Galati, Galati, Romania
| | - Anca Ioana Nicolau
- Faculty of Food Science and Engineering, Dunarea de Jos University of Galati, Galati, Romania
| | - Leontina Grigore-Gurgu
- Faculty of Food Science and Engineering, Dunarea de Jos University of Galati, Galati, Romania
| | - Gerd M Seibold
- Institute of Microbiology and Biotechnology, University of Ulm, Ulm, Germany
| | - Christian U Riedel
- Institute of Microbiology and Biotechnology, University of Ulm, Ulm, Germany
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