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Lakicevic BZ, Den Besten HMW, De Biase D. Landscape of Stress Response and Virulence Genes Among Listeria monocytogenes Strains. Front Microbiol 2022; 12:738470. [PMID: 35126322 PMCID: PMC8811131 DOI: 10.3389/fmicb.2021.738470] [Citation(s) in RCA: 15] [Impact Index Per Article: 7.5] [Reference Citation Analysis] [Abstract] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/08/2021] [Accepted: 11/30/2021] [Indexed: 12/23/2022] Open
Abstract
The pathogenic microorganism Listeria monocytogenes is ubiquitous and responsible for listeriosis, a disease with a high mortality rate in susceptible people. It can persist in different habitats, including the farm environment, the food production environments, and in foods. This pathogen can grow under challenging conditions, such as low pH, low temperatures, and high salt concentrations. However, L. monocytogenes has a high degree of strain divergence regarding virulence potential, environmental adaption, and stress response. This review seeks to provide the reader with an up-to-date overview of clonal and serotype-specific differences among L. monocytogenes strains. Emphasis on the genes and genomic islands responsible for virulence and resistance to environmental stresses is given to explain the complex adaptation among L. monocytogenes strains. Moreover, we highlight the use of advanced diagnostic technologies, such as whole-genome sequencing, to fine-tune quantitative microbiological risk assessment for better control of listeriosis.
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Affiliation(s)
- Brankica Z. Lakicevic
- Institute of Meat Hygiene and Technology, Belgrade, Serbia
- *Correspondence: Brankica Z. Lakicevic,
| | | | - Daniela De Biase
- Department of Medico-Surgical Sciences and Biotechnologies, Sapienza University of Rome, Latina, Italy
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Jarvis KG, Hsu CK, Pettengill JB, Ihrie J, Karathia H, Hasan NA, Grim CJ. Microbiome Population Dynamics of Cold-Smoked Sockeye Salmon during Refrigerated Storage and after Culture Enrichment. J Food Prot 2021; 85:238-253. [PMID: 34614175 DOI: 10.4315/jfp-21-228] [Citation(s) in RCA: 2] [Impact Index Per Article: 0.7] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/01/2021] [Accepted: 10/05/2021] [Indexed: 11/11/2022]
Abstract
ABSTRACT Cold-smoked salmon is a ready-to-eat seafood product of high commercial importance. The processing and storage steps facilitate the introduction, growth, and persistence of foodborne pathogens and spoilage bacteria. The growth of commensal bacteria during storage and once the product is opened also influence the quality and safety of cold-smoked salmon. Here we investigated the microbial community through targeted 16S rRNA gene and shotgun metagenomic sequencing as means to better understand the interactions among bacteria in cold-smoked salmon. Cold-smoked salmon samples were tested over 30 days of aerobic storage at 4°C and cultured at each time point in a buffered Listeria enrichment broth (BLEB) commonly used to detect Listeria in foods. The microbiomes were composed of Firmicutes and Proteobacteria, namely, Carnobacterium, Brochothrix, Pseudomonas, Serratia, and Psychrobacter. Pseudomonas species were the most diverse species, with 181 taxa identified. In addition, we identified potential homologs to 10 classes of bacteriocins in microbiomes of cold-smoked salmon stored at 4°C and corresponding BLEB culture enrichments. The findings presented here contribute to our understanding of microbiome population dynamics in cold-smoked salmon, including changes in bacterial taxa during aerobic cold storage and after culture enrichment. This may facilitate improvements to pathogen detection and quality preservation of this food. HIGHLIGHTS
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Affiliation(s)
- Karen G Jarvis
- Center for Food Safety and Applied Nutrition, U.S. Food and Drug Administration, Laurel, Maryland 20708
| | - Chiun-Kang Hsu
- Center for Food Safety and Applied Nutrition, U.S. Food and Drug Administration, Laurel, Maryland 20708
| | - James B Pettengill
- Center for Food Safety and Applied Nutrition, U.S. Food and Drug Administration, College Park, Maryland 20742
| | - John Ihrie
- Center for Food Safety and Applied Nutrition, U.S. Food and Drug Administration, College Park, Maryland 20742
| | - Hiren Karathia
- Cancer Data Science Laboratory, National Cancer Institute, National Institutes of Health, Bethesda, Maryland 20892
| | - Nur A Hasan
- Center for Bioinformatics and Computational Biology, University of Maryland, College Park, Maryland 20742, USA
| | - Christopher J Grim
- Center for Food Safety and Applied Nutrition, U.S. Food and Drug Administration, Laurel, Maryland 20708
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3
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Sheng L, Wang L. The microbial safety of fish and fish products: Recent advances in understanding its significance, contamination sources, and control strategies. Compr Rev Food Sci Food Saf 2020; 20:738-786. [PMID: 33325100 DOI: 10.1111/1541-4337.12671] [Citation(s) in RCA: 65] [Impact Index Per Article: 16.3] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/02/2020] [Revised: 09/22/2020] [Accepted: 10/12/2020] [Indexed: 12/18/2022]
Abstract
Microorganisms play a crucial and unique role in fish and fish product safety. The presence of human pathogens and the formation of histamine caused by spoilage bacteria make the control of both pathogenic and spoilage microorganisms critical for fish product safety. To provide a comprehensive and updated overview of the involvement of microorganisms in fish and fish product safety, this paper reviewed outbreak and recall surveillance data obtained from government agencies from 1998 to 2018 and identified major safety concerns associated with both domestic and imported fish products. The review also summarized all available literature about the prevalence of major and emerging microbial safety concerns, including Salmonella spp., Listeria monocytogenes, and Aeromonas hydrophila, in different fish and fish products and the survival of these pathogens under different storage conditions. The prevalence of antibiotic-resistant bacteria (ARB) and antibiotic-resistant genes (ARGs), two emerging food safety concerns, is also reviewed. Pathogenic and spoilage microorganisms as well as ARB and ARGs can be introduced into fish and fish products in both preharvest and postharvest stages. Many novel intervention strategies have been proposed and tested for the control of different microorganisms on fish and fish products. One key question that needs to be considered when developing and implementing novel control measures is how to ensure that the measures are cost and environment friendly as well as sustainable. Over the years, regulations have been established to provide guidance documents for good farming and processing practices. To be more prepared for the globalization of the food chain, harmonization of regulations is still needed.
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Affiliation(s)
- Lina Sheng
- Department of Food Science and Technology, University of California, Davis, Davis, California, USA
| | - Luxin Wang
- Department of Food Science and Technology, University of California, Davis, Davis, California, USA
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Matle I, Mafuna T, Madoroba E, Mbatha KR, Magwedere K, Pierneef R. Population Structure of Non-ST6 Listeria monocytogenes Isolated in the Red Meat and Poultry Value Chain in South Africa. Microorganisms 2020; 8:microorganisms8081152. [PMID: 32751410 PMCID: PMC7464360 DOI: 10.3390/microorganisms8081152] [Citation(s) in RCA: 13] [Impact Index Per Article: 3.3] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/04/2020] [Revised: 06/22/2020] [Accepted: 06/28/2020] [Indexed: 12/17/2022] Open
Abstract
Meat products have been implicated in many listeriosis outbreaks globally, however there is a dearth of information on the diversity of L. monocytogenes isolates circulating in food products in South Africa. The aim of this study was to investigate the population structure of L. monocytogenes isolated in the meat value chain within the South African market. Based on whole-genome sequence analysis, a total of 217 isolates were classified into two main lineage groupings namely lineages I (n = 97; 44.7%) and II (n = 120; 55.3%). The lineage groups were further differentiated into IIa (n = 95, 43.8%), IVb (n = 69, 31.8%), IIb (n = 28, 12.9%), and IIc (n = 25, 11.5%) sero-groups. The most abundant sequence types (STs) were ST204 (n = 32, 14.7%), ST2 (n = 30, 13.8%), ST1 (n = 25, 11.5%), ST9 (n = 24, 11.1%), and ST321 (n = 21, 9.7%). In addition, 14 clonal complex (CCs) were identified with over-representation of CC1, CC3, and CC121 in "Processed Meat-Beef", "RTE-Poultry", and "Raw-Lamb" meat categories, respectively. Listeria pathogenic islands were present in 7.4% (LIPI-1), 21.7% (LIPI-3), and 1.8% (LIPI-4) of the isolates. Mutation leading to premature stop codons was detected in inlA virulence genes across isolates identified as ST121 and ST321. The findings of this study demonstrated a high-level of genomic diversity among L. monocytogenes isolates recovered across the meat value chain control points in South Africa.
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Affiliation(s)
- Itumeleng Matle
- Bacteriology Division, Agricultural Research Council-Onderstepoort Veterinary Research, Onderstepoort 0110, South Africa;
- Department of Agriculture and Animal Health, Science Campus, University of South Africa, Florida 1709, South Africa;
| | - Thendo Mafuna
- Centre for Bioinformatics and Computational Biology, Department of Biochemistry, Genetics and Microbiology, University of Pretoria, Pretoria 0028, South Africa;
- Biotechnology Platform, Agricultural Research Council-Onderstepoort Veterinary Research, Private Bag X 05, Onderstepoort 0110, Pretoria, South Africa
| | - Evelyn Madoroba
- Department of Biochemistry and Microbiology, Faculty of Science and Agriculture, University of Zululand, KwaDlangezwa 3886, South Africa;
| | - Khanyisile R. Mbatha
- Department of Agriculture and Animal Health, Science Campus, University of South Africa, Florida 1709, South Africa;
| | - Kudakwashe Magwedere
- Directorate of Veterinary Public Health, Department of Agriculture, Land Reform and Rural Development, Pretoria 0001, South Africa;
| | - Rian Pierneef
- Biotechnology Platform, Agricultural Research Council-Onderstepoort Veterinary Research, Private Bag X 05, Onderstepoort 0110, Pretoria, South Africa
- Correspondence: ; Tel.: +27-12-5299-356
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Yang H, Hoffmann M, Allard MW, Brown EW, Chen Y. Microevolution and Gain or Loss of Mobile Genetic Elements of Outbreak-Related Listeria monocytogenes in Food Processing Environments Identified by Whole Genome Sequencing Analysis. Front Microbiol 2020; 11:866. [PMID: 32547499 PMCID: PMC7272582 DOI: 10.3389/fmicb.2020.00866] [Citation(s) in RCA: 12] [Impact Index Per Article: 3.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/03/2019] [Accepted: 04/14/2020] [Indexed: 01/03/2023] Open
Abstract
Whole genome sequencing (WGS) analyses have been instrumental in traceback investigations of Listeria monocytogenes (Lm). To demonstrate how long-read sequencing analysis can capture and describe relationships among isolates from clinical, food, and environmental sources, we analyzed 366 long-read- and shotgun-sequenced isolates from 16 Lm outbreak strains associated with cantaloupe, leafy green, stone fruit, caramel apple, mung bean sprout, multiple cheese products, multiple ice cream products, and their production environments. The analyses demonstrated that outbreak strains could be distributed in different areas and zones of food production environments through persistent or repeated contamination. Multi-strain and multi-clone contamination were common. Further, WGS could differentiate among isolates collected at different time points or from different production lines in the same facility, revealing microevolution events in processing environments. Our comparison between complete and shotgun genomes showed that isolates of the same outbreak strain diversified mostly by gain/loss of plasmids and chromosome-borne prophages that constitute 2 to 5% of the chromosome. In contrast, other genes missing in the shotgun genomes were randomly scattered, constituting ~0.5% of the chromosome. Among different outbreak strains of the same CC, most gene-scale differences were due to gain/loss of mobile genetic elements, such as plasmids, chromosome-borne prophages, a Tn916 like transposon, and Listeria Genomic Island 2. The nucleotide variations in the same prophage and the same plasmid shared among isolates of the same outbreak strain were limited, which enabled different WGS tools to unambiguously cluster isolates of the same outbreak strain. In some outbreak strains, correlation between prophage gain/loss and single nucleotide polymorphism (SNP) accumulations in the genome backbone were observed.
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Affiliation(s)
- Helen Yang
- Center for Food Safety and Applied Nutrition, Food and Drug Administration, College Park, MD, United States
| | - Maria Hoffmann
- Center for Food Safety and Applied Nutrition, Food and Drug Administration, College Park, MD, United States
| | - Marc W Allard
- Center for Food Safety and Applied Nutrition, Food and Drug Administration, College Park, MD, United States
| | - Eric W Brown
- Center for Food Safety and Applied Nutrition, Food and Drug Administration, College Park, MD, United States
| | - Yi Chen
- Center for Food Safety and Applied Nutrition, Food and Drug Administration, College Park, MD, United States
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Brauge T, Faille C, Leleu G, Denis C, Hanin A, Midelet G. Treatment with disinfectants may induce an increase in viable but non culturable populations of Listeria monocytogenes in biofilms formed in smoked salmon processing environments. Food Microbiol 2020; 92:103548. [PMID: 32950145 DOI: 10.1016/j.fm.2020.103548] [Citation(s) in RCA: 19] [Impact Index Per Article: 4.8] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/20/2019] [Revised: 05/01/2020] [Accepted: 05/05/2020] [Indexed: 10/24/2022]
Abstract
The objectives of this study were 1) to evaluate the impact of two industrial disinfectants on the viability of Listeria monocytogenes populations in biofilm and 2) to investigate the viability state of L. monocytogenes cells present on contact surfaces in the smoked salmon processing environment. In the first step, we cultured mono species and mixed species biofilms containing L. monocytogenes on stainless steel or polyvinyl chloride (PVC) at 8 °C for 48h. The biofilms were then exposed to quaternary ammonium- and hydrogen peroxide-based disinfectants. Residual total populations of L. monocytogenes were measured by qPCR, and viable culturable (VC) cell populations were quantified using standard microbiological culture-based techniques and by a quantitative PCR (qPCR) assay coupled with a propidium monoazide treatment. Decreases in VC populations and the appearance of viable but non culturable (VBNC) populations were observed in response to treatment with the disinfectants. An 8 month sampling campaign in 4 smoked salmon processing plants was also carried out to detect L. monocytogenes in environmental samples. VBNC cells were detected mainly after the cleaning and disinfection operations. This study showed that industrial disinfectants did not inactivate all L. monocytogenes cells on inert surfaces. The presence of VBNC populations of L. monocytogenes in the smoked salmon processing environment is a public health concern.
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Affiliation(s)
- Thomas Brauge
- ANSES, Laboratory for Food Safety, 62200, Boulogne-sur-mer, France.
| | - Christine Faille
- Univ. Lille, CNRS, INRAE, ENSCL, UMET, 59650, Villeneuve d'Ascq, France
| | - Guylaine Leleu
- ANSES, Laboratory for Food Safety, 62200, Boulogne-sur-mer, France
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Evolution of Listeria monocytogenes in a Food Processing Plant Involves Limited Single-Nucleotide Substitutions but Considerable Diversification by Gain and Loss of Prophages. Appl Environ Microbiol 2020; 86:AEM.02493-19. [PMID: 31900305 PMCID: PMC7054086 DOI: 10.1128/aem.02493-19] [Citation(s) in RCA: 48] [Impact Index Per Article: 12.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/28/2019] [Accepted: 12/20/2019] [Indexed: 12/23/2022] Open
Abstract
Knowledge about the genetic evolution of L. monocytogenes in food processing facilities over multiple years is generally lacking. This information is critical to interpret WGS findings involving food or food-associated isolates. This study suggests that L. monocytogenes that persists in processing facilities may evolve with a low single-nucleotide mutation rate mostly driven by negative (i.e., purifying) selection but with rapid diversification of prophages. Hence, isolation of L. monocytogenes with few single-nucleotide polymorphism (SNP) differences in different locations (e.g., supplier plants and receiving plants) is possible, highlighting the importance of epidemiological and detailed isolate metadata for interpreting WGS data in traceback investigation. Our study also shows how advanced WGS data analyses can be used to support root cause analysis efforts and may, for example, pinpoint the time when a persistence event started (which then potentially could be linked to facility changes, introduction of new equipment, etc.). Whole-genome sequencing (WGS) is becoming the standard method for subtyping Listeria monocytogenes. Interpretation of WGS data for isolates from foods and associated environments is, however, challenging due to a lack of detailed data on Listeria evolution in processing facilities. Here, we used previously collected WGS data for 40 L. monocytogenes isolates obtained from a cold-smoked salmon processing facility between 1998 and 2015 to probe the L. monocytogenes molecular evolution in this facility, combined with phenotypic assessment of selected isolates. Isolates represented three clusters (1, 2, and 3); cluster 3 isolates (n = 32) were obtained over 18 years. The average mutation rate for cluster 3 was estimated as 1.15 × 10−7 changes per nucleotide per year (∼0.35 changes per genome per year); the most recent common ancestors (MRCAs) of subclusters 3a and 3b were estimated to have occurred around 1958 and 1974, respectively, within the age of the facility, suggesting long-term persistence in this facility. Extensive prophage diversity was observed within subclusters 3a and 3b, which have one shared and six unique prophage profiles for each subcluster (with 16 prophage profiles found among all 40 isolates). The plasmid-borne sanitizer tolerance operon bcrABC was found in all cluster 2 and 3 isolates, while the transposon-borne sanitizer tolerance gene qacH was found in one cluster 1 isolate; presence of these genes was correlated with the ability to survive increased concentrations of sanitizers. Selected isolates showed significant variation in the ability to attach to surfaces, with persistent isolates attaching better than transient isolates at 21°C. IMPORTANCE Knowledge about the genetic evolution of L. monocytogenes in food processing facilities over multiple years is generally lacking. This information is critical to interpret WGS findings involving food or food-associated isolates. This study suggests that L. monocytogenes that persists in processing facilities may evolve with a low single-nucleotide mutation rate mostly driven by negative (i.e., purifying) selection but with rapid diversification of prophages. Hence, isolation of L. monocytogenes with few single-nucleotide polymorphism (SNP) differences in different locations (e.g., supplier plants and receiving plants) is possible, highlighting the importance of epidemiological and detailed isolate metadata for interpreting WGS data in traceback investigation. Our study also shows how advanced WGS data analyses can be used to support root cause analysis efforts and may, for example, pinpoint the time when a persistence event started (which then potentially could be linked to facility changes, introduction of new equipment, etc.).
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Manso B, Melero B, Stessl B, Fernández-Natal I, Jaime I, Hernández M, Wagner M, Rovira J, Rodríguez-Lázaro D. Characterization of Virulence and Persistence Abilities of Listeria monocytogenes Strains Isolated from Food Processing Premises. J Food Prot 2019; 82:1922-1930. [PMID: 31633423 DOI: 10.4315/0362-028x.jfp-19-109] [Citation(s) in RCA: 12] [Impact Index Per Article: 2.4] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/11/2022]
Abstract
We report the characterization of 15 Listeria monocytogenes strains isolated from various food processing plants by multivirulence locus sequence typing to determine virulence types (VTs) and epidemic clones. Molecular mechanisms involved in adaptation to food processing environments and related to virulence were also studied. Phenotypic behaviors associated with various antimicrobials, biofilm formations, and invasiveness were assessed. There were 11 VTs among the 15 L. monocytogenes strains. Strains belonging to six VTs were stress survival islet 1 (SSI-1) and one strain of VT94 was SSI-2. Tn6188 was found in VT6 and VT94 strains, and bcrABC cassette genes were identified in VT21, VT60, and VT63 strains. Only one strain, in VT20, showed llxS, whereas a full-size inlA was detected in strains belonging to VT8, VT20, VT21, and VT63. VT10, VT20, VT21, VT60, and VT63 strains were the most tolerant to studied disinfectants. A VT6 strain showed the strongest biofilm formation ability in polyvinyl chloride, and strains belonging to VT10, VT11, VT20, and VT94 had moderate abilities. Antimicrobial sensitivity tests showed that all the L. monocytogenes strains were multidrug resistant. F tests revealed that only strains of VT10, VT60, and VT94 were significantly noninvasive (P < 0.05) in Caco-2 cells. Our findings illustrate how L. monocytogenes isolates exploit diverse mechanisms to adapt to adverse conditions. Consequently, detailed characterization of L. monocytogenes isolates is required for comprehensive elimination of this pathogenic bacterium in food processing environments.
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Affiliation(s)
- Beatriz Manso
- Department of Biotechnology and Food Science, Faculty of Sciences, University of Burgos, Burgos, Spain (ORCID. https://orcid.org/0000-0002-8795-854X [D.R.-L.])
| | - Beatriz Melero
- Department of Biotechnology and Food Science, Faculty of Sciences, University of Burgos, Burgos, Spain (ORCID. https://orcid.org/0000-0002-8795-854X [D.R.-L.])
| | - Beatrix Stessl
- Institute of Milk Hygiene, Milk Technology and Food Science, Department for Farm Animals and Veterinary Public Health, University of Veterinary Medicine, Vienna, Austria.,Christian Doppler Laboratory for Molecular Food Analytics, University of Veterinary Medicine, Vienna, Austria
| | - Isabel Fernández-Natal
- Complejo Asistencial, University of León, Leon, Spain.,Institute of Biomedicine (IBIOMED), University of León, Leon, Spain
| | - Isabel Jaime
- Department of Biotechnology and Food Science, Faculty of Sciences, University of Burgos, Burgos, Spain (ORCID. https://orcid.org/0000-0002-8795-854X [D.R.-L.])
| | - Marta Hernández
- Department of Biotechnology and Food Science, Faculty of Sciences, University of Burgos, Burgos, Spain (ORCID. https://orcid.org/0000-0002-8795-854X [D.R.-L.]).,Laboratory of Molecular Biology and Microbiology, Instituto Tecnológico Agrario de Castilla y León (ITACyL), Valladolid, Spain
| | - Martin Wagner
- Institute of Milk Hygiene, Milk Technology and Food Science, Department for Farm Animals and Veterinary Public Health, University of Veterinary Medicine, Vienna, Austria.,Christian Doppler Laboratory for Molecular Food Analytics, University of Veterinary Medicine, Vienna, Austria
| | - Jordi Rovira
- Department of Biotechnology and Food Science, Faculty of Sciences, University of Burgos, Burgos, Spain (ORCID. https://orcid.org/0000-0002-8795-854X [D.R.-L.])
| | - David Rodríguez-Lázaro
- Department of Biotechnology and Food Science, Faculty of Sciences, University of Burgos, Burgos, Spain (ORCID. https://orcid.org/0000-0002-8795-854X [D.R.-L.])
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Fan Z, Xie J, Li Y, Wang H. Listeriosis in mainland China: A systematic review. Int J Infect Dis 2019; 81:17-24. [PMID: 30641204 DOI: 10.1016/j.ijid.2019.01.007] [Citation(s) in RCA: 43] [Impact Index Per Article: 8.6] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/19/2018] [Revised: 12/26/2018] [Accepted: 01/05/2019] [Indexed: 12/28/2022] Open
Abstract
OBJECTIVE The aim of this study was to conduct a systematic review to better understand the epidemiological and clinical characteristics of listeriosis patients in mainland China. METHODS The six most widely used Chinese and English language databases were searched. The records of patients with listeriosis in mainland China reported during the years 2011-2017 were extracted. The clinical data of patients and information on clinical isolates of Listeria were collected and analyzed. RESULTS In total, 136 records were identified, reporting 562 patients with listeriosis. The number of patients was much higher than that reported in the previous decade. The 227 non-perinatal listeriosis patients included had a mortality rate of 23.78%. Of the 231 perinatal listeriosis patients, 32.68% resulted in abortion and/or newborn death. All listeriosis cases were reported as being sporadic. The listeriosis was traced to infection via a meat product in only three patients, while 33.12% were healthcare-associated infections. CONCLUSIONS The number of patients with listeriosis in mainland China may have been underestimated previously. Perinatal cases in mainland China account for a much higher proportion than is usually described. Considering the high number of listeriosis patients in China, a comprehensive monitoring system for Listeria is urgently needed.
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Affiliation(s)
- Zhangling Fan
- Department of Infectious Diseases, Peking Union Medical College Hospital, Chinese Academy of Medical Sciences and Peking Union Medical College, Beijing, China
| | - Jing Xie
- Department of Infectious Diseases, Peking Union Medical College Hospital, Chinese Academy of Medical Sciences and Peking Union Medical College, Beijing, China
| | - Yue Li
- The Institute of Medical Information (IMI) and Library, Chinese Academy of Medical Sciences and Peking Union Medical College, Beijing, China
| | - Huanling Wang
- Department of Infectious Diseases, Peking Union Medical College Hospital, Chinese Academy of Medical Sciences and Peking Union Medical College, Beijing, China.
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Molecular characterization of Listeria monocytogenes isolates from a small-scale meat processor in Montenegro, 2011-2014. Food Microbiol 2018; 79:116-122. [PMID: 30621866 DOI: 10.1016/j.fm.2018.12.005] [Citation(s) in RCA: 17] [Impact Index Per Article: 2.8] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/17/2018] [Revised: 11/29/2018] [Accepted: 12/04/2018] [Indexed: 12/31/2022]
Abstract
The presence of Listeria monocytogenes was evaluated in a small-scale meat processing facility in Montenegro during 2011-2014. L. monocytogenes isolates from traditional meat products and environmental swabs were subjected to a) molecular characterization b) serotyping by both multiplex PCR and next generation sequencing (NGS) c) potential antimicrobial resistance (AMR) was assessed by extraction of specific genes from NGS data and d) screening for the presence of some disinfectant resistance markers. Overall, traditional meat products were contaminated, most likely from incoming raw materials, with 4 major specific STs of L. monocytogenes (ST515, ST8, ST21, ST121) representing 4 clonal complexes (CC1, CC8, CC21, CC121) identified during the four-year period. These strains belonged to serogroup IIa which predominated, followed by IVb (ST515, CC1). The strains from environmental swabs belonged, exclusively, to ST21 and were isolated from cutting board and floor swabs in 2011. Furthermore, we found Tn6188, a novel transposon conferring tolerance to BC, to be specific to sequence type ST121. In addition, antimicrobial resistance genes mprF and fosX were present in clonal complexes CC21 and CC121, while complexes CC8 and CC1 exclusively harbored the mprF antimicrobial resistance gene.
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11
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Evaluation of ultraviolet light (UV), non-thermal atmospheric plasma (NTAP) and their combination for the control of foodborne pathogens in smoked salmon and their effect on quality attributes. INNOV FOOD SCI EMERG 2018. [DOI: 10.1016/j.ifset.2018.10.002] [Citation(s) in RCA: 19] [Impact Index Per Article: 3.2] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/22/2022]
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12
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Bucur FI, Grigore-Gurgu L, Crauwels P, Riedel CU, Nicolau AI. Resistance of Listeria monocytogenes to Stress Conditions Encountered in Food and Food Processing Environments. Front Microbiol 2018; 9:2700. [PMID: 30555426 PMCID: PMC6282059 DOI: 10.3389/fmicb.2018.02700] [Citation(s) in RCA: 143] [Impact Index Per Article: 23.8] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/31/2018] [Accepted: 10/23/2018] [Indexed: 12/17/2022] Open
Abstract
Listeria monocytogenes is a human food-borne facultative intracellular pathogen that is resistant to a wide range of stress conditions. As a consequence, L. monocytogenes is extremely difficult to control along the entire food chain from production to storage and consumption. Frequent and recent outbreaks of L. monocytogenes infections illustrate that current measures of decontamination and preservation are suboptimal to control L. monocytogenes in food. In order to develop efficient measures to prevent contamination during processing and control growth during storage of food it is crucial to understand the mechanisms utilized by L. monocytogenes to tolerate the stress conditions in food matrices and food processing environments. Food-related stress conditions encountered by L. monocytogenes along the food chain are acidity, oxidative and osmotic stress, low or high temperatures, presence of bacteriocins and other preserving additives, and stresses as a consequence of applying alternative decontamination and preservation technologies such high hydrostatic pressure, pulsed and continuous UV light, pulsed electric fields (PEF). This review is aimed at providing a summary of the current knowledge on the response of L. monocytogenes toward these stresses and the mechanisms of stress resistance employed by this important food-borne bacterium. Circumstances when L. monocytogenes cells become more sensitive or more resistant are mentioned and existence of a cross-resistance when multiple stresses are present is pointed out.
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Affiliation(s)
- Florentina Ionela Bucur
- 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
| | - Peter Crauwels
- Institute of Microbiology and Biotechnology, Ulm University, Ulm, Germany
| | | | - Anca Ioana Nicolau
- Faculty of Food Science and Engineering, Dunarea de Jos University of Galati, Galati, Romania
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Challenge Studies to Determine the Ability of Foods to Support the Growth of Listeria monocytogenes. Pathogens 2018; 7:pathogens7040080. [PMID: 30301168 PMCID: PMC6313757 DOI: 10.3390/pathogens7040080] [Citation(s) in RCA: 8] [Impact Index Per Article: 1.3] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/27/2018] [Revised: 10/01/2018] [Accepted: 10/01/2018] [Indexed: 11/30/2022] Open
Abstract
Listeria monocytogenes is a foodborne pathogen that causes listeriosis, a relatively rare, but potentially fatal, disease, with a mortality rate of 20–30%. In general, European Regulations require the absence of L. monocytogenes in five samples of 25 g before the food has left the producer, but if the food has been demonstrated not to support the growth of L. monocytogenes, up to 100 cfu g−1 are allowed in the food (except for foods for infants or medical purposes) during its shelf-life under reasonably foreseeable storage conditions. It is important for food producers to determine if their food supports the growth of L. monocytogenes. The European Union Reference Laboratory for L. monocytogenes published a Technical Guidance document for conducting shelf-life studies on L. monocytogenes in ready-to-eat foods in June 2014. Primarily based on the EURL guidance document for conducting challenge studies, the ability of cheese (feta and soft goat’s milk cheese), cold-smoked salmon, coleslaw, and pork pate to support the growth of L. monocytogenes was determined using a starting inoculum of approximately 100 cfu g−1. The cheese and pork pate were incubated at 8 °C for 14 days; the smoked salmon was incubated at 6 °C for 5 days and 8 °C for 9 days; and the coleslaw was incubated at 8 °C for 7 days and 12 °C for 14 days. The results showed that the smoked salmon and pork pate supported growth, while coleslaw and cheese did not. From this study, it is evident that there are factors in food other than pH, water activity, and total bacterial count (TBC) that can inhibit the ability of L. monocytogenes to grow in food.
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14
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Tamburro M, Sammarco ML, Ripabelli G. High resolution melting analysis for the characterization of lineage II Listeria monocytogenes serovars 1/2a and 1/2c based on single nucleotide polymorphisms identification within the Listeria Pathogenicity Island-1 and inlAB operon: a novel approach for epidemiological surveillance. J Appl Microbiol 2018; 125:1920-1937. [PMID: 30187619 DOI: 10.1111/jam.14100] [Citation(s) in RCA: 2] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/22/2018] [Revised: 07/02/2018] [Accepted: 08/18/2018] [Indexed: 01/16/2023]
Abstract
AIMS A high resolution melting (HRM) assay was developed for characterizing lineage II Listeria monocytogenes based on the amplification and the melting profiles analysis of 81 fragments targeting the region from the prs to ldh loci, including the Listeria Pathogenicity Island-1 (LIPI-1) genes and the inlAB operon. METHODS AND RESULTS Real-time PCR and HRM protocols were standardized using 10 replicate assays from L. monocytogenes EGD-e reference strain (serovar 1/2a). Twenty wild-type isolates of serovar 1/2a and two of serovar 1/2c were tested, and differences between EGD-e strain and the wild-type isolates were defined if the melting temperature (Tm ) of an amplicon was not within the lower and the upper limits calculated from replicate testing on EGD-e. The analysis revealed 17 and 19 HRM profiles with respect to prs/LIPI-1/ldh and inlAB target regions (Simpson's Index of Diversity 0·979 and 0·983) respectively. The 1/2c cultures showed 98·1% similarity to melting characteristics with EGD-e, whilst 1/2a isolates had the greatest heterogeneity that was related to inlA, inlB and actA genes. Sequencing of amplicons generating different Tm values from EGD-e confirmed the presence of point mutations. CONCLUSIONS This method was useful for L. monocytogenes subtyping based on single nucleotide polymorphisms detection through the melting behaviour analysis of main virulence genes. SIGNIFICANCE AND IMPACT OF THE STUDY The study underlines the effectiveness of HRM in differentiating L. monocytogenes strains with high discriminatory power, thus rendering it useful for epidemiological surveillance.
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Affiliation(s)
- M Tamburro
- Department of Medicine and Health Sciences "Vincenzo Tiberio", University of Molise, Campobasso, Italy
| | - M L Sammarco
- Department of Medicine and Health Sciences "Vincenzo Tiberio", University of Molise, Campobasso, Italy
| | - G Ripabelli
- Department of Medicine and Health Sciences "Vincenzo Tiberio", University of Molise, Campobasso, Italy
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15
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Genomic Characterization of Listeria monocytogenes Isolates Associated with Clinical Listeriosis and the Food Production Environment in Ireland. Genes (Basel) 2018; 9:genes9030171. [PMID: 29558450 PMCID: PMC5867892 DOI: 10.3390/genes9030171] [Citation(s) in RCA: 49] [Impact Index Per Article: 8.2] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/21/2017] [Revised: 03/05/2018] [Accepted: 03/07/2018] [Indexed: 01/18/2023] Open
Abstract
Listeria monocytogenes is a major human foodborne pathogen that is prevalent in the natural environment and has a high case fatality rate. Whole genome sequencing (WGS) analysis has emerged as a valuable methodology for the classification of L. monocytogenes isolates and the identification of virulence islands that may influence infectivity. In this study, WGS was used to provide an insight into 25 L. monocytogenes isolates from cases of clinical infection in Ireland between 2013 and 2015. Clinical strains were either lineage I (14 isolates) or lineage II (11 isolates), with 12 clonal complexes (CC) represented, of which CC1 (6) and CC101 (4) were the most common. Single nucleotide polymorphism (SNP) analysis demonstrated that clinical isolates from mother-infant pairs (one isolate from the mother and one from the infant) were highly related (3 SNP differences in each) and also identified close similarities between isolates from otherwise distinct cases (1 SNP difference). Clinical strains were positive for common virulence-associated loci and 13 isolates harbour the LIPI-3 locus. Pulsed-field gel electrophoresis (PFGE) was used to compare strains to a database of 1300 Irish food and food processing environment isolates and determined that 64% of clinical pulsotypes were previously encountered in the food or food processing environment. Five of the matching food and food processing environment isolates were sequenced and results demonstrated a correlation between pulsotype and genotype. Overall, the work provides insights into the nature of L. monocytogenes strains currently causing clinical disease in Ireland and indicates that similar isolates can be found in the food or food processing environment.
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16
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Papaioannou E, Giaouris ED, Berillis P, Boziaris IS. Dynamics of biofilm formation by Listeria monocytogenes on stainless steel under mono-species and mixed-culture simulated fish processing conditions and chemical disinfection challenges. Int J Food Microbiol 2017; 267:9-19. [PMID: 29275280 DOI: 10.1016/j.ijfoodmicro.2017.12.020] [Citation(s) in RCA: 43] [Impact Index Per Article: 6.1] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/05/2017] [Revised: 12/04/2017] [Accepted: 12/17/2017] [Indexed: 12/14/2022]
Abstract
The progressive ability of a six-strains L. monocytogenes cocktail to form biofilm on stainless steel (SS), under fish-processing simulated conditions, was investigated, together with the biocide tolerance of the developed sessile communities. To do this, the pathogenic bacteria were left to form biofilms on SS coupons incubated at 15°C, for up to 240h, in periodically renewable model fish juice substrate, prepared by aquatic extraction of sea bream flesh, under both mono-species and mixed-culture conditions. In the latter case, L. monocytogenes cells were left to produce biofilms together with either a five-strains cocktail of four Pseudomonas species (fragi, savastanoi, putida and fluorescens), or whole fish indigenous microflora. The biofilm populations of L. monocytogenes, Pseudomonas spp., Enterobacteriaceae, H2S producing and aerobic plate count (APC) bacteria, both before and after disinfection, were enumerated by selective agar plating, following their removal from surfaces through bead vortexing. Scanning electron microscopy was also applied to monitor biofilm formation dynamics and anti-biofilm biocidal actions. Results revealed the clear dominance of Pseudomonas spp. bacteria in all the mixed-culture sessile communities throughout the whole incubation period, with the in parallel sole presence of L. monocytogenes cells to further increase (ca. 10-fold) their sessile growth. With respect to L. monocytogenes and under mono-species conditions, its maximum biofilm population (ca. 6logCFU/cm2) was reached at 192h of incubation, whereas when solely Pseudomonas spp. cells were also present, its biofilm formation was either slightly hindered or favored, depending on the incubation day. However, when all the fish indigenous microflora was present, biofilm formation by the pathogen was greatly hampered and never exceeded 3logCFU/cm2, while under the same conditions, APC biofilm counts had already surpassed 7logCFU/cm2 by the end of the first 96h of incubation. All here tested disinfection treatments, composed of two common food industry biocides gradually applied for 15 to 30min, were insufficient against L. monocytogenes mono-species biofilm communities, with the resistance of the latter to significantly increase from the 3rd to 7th day of incubation. However, all these treatments resulted in no detectable L. monocytogenes cells upon their application against the mixed-culture sessile communities also containing the fish indigenous microflora, something probably associated with the low attached population level of these pathogenic cells before disinfection (<102CFU/cm2) under such mixed-culture conditions. Taken together, all these results expand our knowledge on both the population dynamics and resistance of L. monocytogenes biofilm cells under conditions resembling those encountered within the seafood industry and should be considered upon designing and applying effective anti-biofilm strategies.
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Affiliation(s)
- Eleni Papaioannou
- Department of Ichthyology and Aquatic Environment, School of Agricultural Sciences, University of Thessaly, Greece
| | - Efstathios D Giaouris
- Department of Food Science and Nutrition, School of the Environment, University of the Aegean, Myrina, Lemnos, Greece.
| | - Panagiotis Berillis
- Department of Ichthyology and Aquatic Environment, School of Agricultural Sciences, University of Thessaly, Greece
| | - Ioannis S Boziaris
- Department of Ichthyology and Aquatic Environment, School of Agricultural Sciences, University of Thessaly, Greece
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17
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Rychli K, Wagner EM, Ciolacu L, Zaiser A, Tasara T, Wagner M, Schmitz-Esser S. Comparative genomics of human and non-human Listeria monocytogenes sequence type 121 strains. PLoS One 2017; 12:e0176857. [PMID: 28472116 PMCID: PMC5417603 DOI: 10.1371/journal.pone.0176857] [Citation(s) in RCA: 32] [Impact Index Per Article: 4.6] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/05/2016] [Accepted: 04/18/2017] [Indexed: 01/01/2023] Open
Abstract
The food-borne pathogen Listeria (L.) monocytogenes is able to survive for months and even years in food production environments. Strains belonging to sequence type (ST)121 are particularly found to be abundant and to persist in food and food production environments. To elucidate genetic determinants characteristic for L. monocytogenes ST121, we sequenced the genomes of 14 ST121 strains and compared them with currently available L. monocytogenes ST121 genomes. In total, we analyzed 70 ST121 genomes deriving from 16 different countries, different years of isolation, and different origins—including food, animal and human ST121 isolates. All ST121 genomes show a high degree of conservation sharing at least 99.7% average nucleotide identity. The main differences between the strains were found in prophage content and prophage conservation. We also detected distinct highly conserved subtypes of prophages inserted at the same genomic locus. While some of the prophages showed more than 99.9% similarity between strains from different sources and years, other prophages showed a higher level of diversity. 81.4% of the strains harbored virtually identical plasmids. 97.1% of the ST121 strains contain a truncated internalin A (inlA) gene. Only one of the seven human ST121 isolates encodes a full-length inlA gene, illustrating the need of better understanding their survival and virulence mechanisms.
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Affiliation(s)
- Kathrin Rychli
- Institute for Milk Hygiene, University of Veterinary Medicine Vienna, Wien, Austria
| | - Eva M. Wagner
- Institute for Milk Hygiene, University of Veterinary Medicine Vienna, Wien, Austria
| | - Luminita Ciolacu
- Institute for Milk Hygiene, University of Veterinary Medicine Vienna, Wien, Austria
| | - Andreas Zaiser
- Institute for Milk Hygiene, University of Veterinary Medicine Vienna, Wien, Austria
| | - Taurai Tasara
- Vetsuisse Faculty, Institute for Food Safety and Hygiene, University of Zurich, Zurich, Switzerland
| | - Martin Wagner
- Institute for Milk Hygiene, University of Veterinary Medicine Vienna, Wien, Austria
| | - Stephan Schmitz-Esser
- Institute for Milk Hygiene, University of Veterinary Medicine Vienna, Wien, Austria
- * E-mail:
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18
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Jennison AV, Masson JJ, Fang NX, Graham RM, Bradbury MI, Fegan N, Gobius KS, Graham TM, Guglielmino CJ, Brown JL, Fox EM. Analysis of the Listeria monocytogenes Population Structure among Isolates from 1931 to 2015 in Australia. Front Microbiol 2017; 8:603. [PMID: 28428781 PMCID: PMC5382192 DOI: 10.3389/fmicb.2017.00603] [Citation(s) in RCA: 25] [Impact Index Per Article: 3.6] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/02/2017] [Accepted: 03/23/2017] [Indexed: 01/01/2023] Open
Abstract
Listeriosis remains among the most important bacterial illnesses, with a high associated mortality rate. Efforts to control listeriosis require detailed knowledge of the epidemiology of the disease itself, and its etiological bacterium, Listeria monocytogenes. In this study we provide an in-depth analysis of the epidemiology of 224 L. monocytogenes isolates from Australian clinical and non-clinical sources. Non-human sources included meat, dairy, seafood, fruit, and vegetables, along with animal and environmental isolates. Serotyping, Multi-Locus Sequence Typing, and analysis of inlA gene sequence were performed. Serogroups IIA, IIB, and IVB comprised 94% of all isolates, with IVB over-represented among clinical isolates. Serogroup IIA was the most common among dairy and meat isolates. Lineage I isolates were most common among clinical isolates, and 52% of clinical isolates belonged to ST1. Overall 39 STs were identified in this study, with ST1 and ST3 containing the largest numbers of L. monocytogenes isolates. These STs comprised 40% of the total isolates (n = 90), and both harbored isolates from clinical and non-clinical sources. ST204 was the third most common ST. The high prevalence of this group among L. monocytogenes populations has not been reported outside Australia. Twenty-seven percent of the STs in this study contained exclusively clinical isolates. Analysis of the virulence protein InlA among isolates in this study identified a truncated form of the protein among isolates from ST121 and ST325. The ST325 group contained a previously unreported novel mutation leading to production of a 93 amino acid protein. This study provides insights in the population structure of L. monocytogenes isolated in Australia, which will contribute to public health knowledge relating to this important human pathogen.
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Affiliation(s)
- Amy V Jennison
- Public Health Microbiology, Public and Environmental Health, Queensland Health, Forensic and Scientific Services, BrisbaneQLD, Australia
| | - Jesse J Masson
- Commonwealth Scientific and Industrial Research Organisation - Agriculture and Food, WerribeeVIC, Australia
| | - Ning-Xia Fang
- Public Health Microbiology, Public and Environmental Health, Queensland Health, Forensic and Scientific Services, BrisbaneQLD, Australia
| | - Rikki M Graham
- Public Health Microbiology, Public and Environmental Health, Queensland Health, Forensic and Scientific Services, BrisbaneQLD, Australia
| | - Mark I Bradbury
- Commonwealth Scientific and Industrial Research Organisation - Agriculture and Food, SydneyNSW, Australia
| | - Narelle Fegan
- Commonwealth Scientific and Industrial Research Organisation - Agriculture and Food, WerribeeVIC, Australia
| | - Kari S Gobius
- Commonwealth Scientific and Industrial Research Organisation - Agriculture and Food, WerribeeVIC, Australia
| | - Trudy M Graham
- Public Health Microbiology, Public and Environmental Health, Queensland Health, Forensic and Scientific Services, BrisbaneQLD, Australia
| | - Christine J Guglielmino
- Public Health Microbiology, Public and Environmental Health, Queensland Health, Forensic and Scientific Services, BrisbaneQLD, Australia
| | - Janelle L Brown
- Commonwealth Scientific and Industrial Research Organisation - Agriculture and Food, SydneyNSW, Australia
| | - Edward M Fox
- Commonwealth Scientific and Industrial Research Organisation - Agriculture and Food, WerribeeVIC, Australia
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NicAogáin K, O’Byrne CP. The Role of Stress and Stress Adaptations in Determining the Fate of the Bacterial Pathogen Listeria monocytogenes in the Food Chain. Front Microbiol 2016; 7:1865. [PMID: 27933042 PMCID: PMC5120093 DOI: 10.3389/fmicb.2016.01865] [Citation(s) in RCA: 117] [Impact Index Per Article: 14.6] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/05/2016] [Accepted: 11/04/2016] [Indexed: 12/15/2022] Open
Abstract
The foodborne pathogen Listeria monocytogenes is a highly adaptable organism that can persist in a wide range of environmental and food-related niches. The consumption of contaminated ready-to-eat foods can cause infections, termed listeriosis, in vulnerable humans, particularly those with weakened immune systems. Although these infections are comparatively rare they are associated with high mortality rates and therefore this pathogen has a significant impact on food safety. L. monocytogenes can adapt to and survive a wide range of stress conditions including low pH, low water activity, and low temperature, which makes it problematic for food producers who rely on these stresses for preservation. Stress tolerance in L. monocytogenes can be explained partially by the presence of the general stress response (GSR), a transcriptional response under the control of the alternative sigma factor sigma B (σB) that reconfigures gene transcription to provide homeostatic and protective functions to cope with the stress. Within the host σB also plays a key role in surviving the harsh conditions found in the gastrointestinal tract. As the infection progresses beyond the GI tract L. monocytogenes uses an intracellular infectious cycle to propagate, spread and remain protected from the host's humoral immunity. Many of the virulence genes that facilitate this infectious cycle are under the control of a master transcriptional regulator called PrfA. In this review we consider the environmental reservoirs that enable L. monocytogenes to gain access to the food chain and discuss the stresses that the pathogen must overcome to survive and grow in these environments. The overlap that exists between stress tolerance and virulence is described. We review the principal measures that are used to control the pathogen and point to exciting new approaches that might provide improved means of control in the future.
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Affiliation(s)
| | - Conor P. O’Byrne
- Bacterial Stress Response Group, Microbiology, School of Natural Sciences, College of Science, National University of IrelandGalway, Ireland
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20
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Véghová A, Minarovičová J, Koreňová J, Drahovská H, Kaclíková E. Prevalence and tracing of persistentListeria monocytogenesstrains in meat processing facility production chain. J Food Saf 2016. [DOI: 10.1111/jfs.12315] [Citation(s) in RCA: 19] [Impact Index Per Article: 2.4] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/27/2022]
Affiliation(s)
- Adriana Véghová
- National Agricultural and Food Centre - Food Research Institute; Priemyselná 4 Bratislava 82475, Slovakia
| | - Jana Minarovičová
- National Agricultural and Food Centre - Food Research Institute; Priemyselná 4 Bratislava 82475, Slovakia
| | - Janka Koreňová
- National Agricultural and Food Centre - Food Research Institute; Priemyselná 4 Bratislava 82475, Slovakia
| | - Hana Drahovská
- Faculty of Natural Sciences; Comenius University; Mlynská dolina B-2 Bratislava 84215, Slovakia
| | - Eva Kaclíková
- National Agricultural and Food Centre - Food Research Institute; Priemyselná 4 Bratislava 82475, Slovakia
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