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Wu Z, Zhou W, Pang C, Deng W, Xu C, Wang X. Multifunctional chitosan-based coating with liposomes containing laurel essential oils and nanosilver for pork preservation. Food Chem 2019; 295:16-25. [DOI: 10.1016/j.foodchem.2019.05.114] [Citation(s) in RCA: 62] [Impact Index Per Article: 12.4] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/17/2019] [Revised: 04/08/2019] [Accepted: 05/15/2019] [Indexed: 10/26/2022]
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Ethanol Adaptation Strategies in Salmonella enterica Serovar Enteritidis Revealed by Global Proteomic and Mutagenic Analyses. Appl Environ Microbiol 2019; 85:AEM.01107-19. [PMID: 31375481 DOI: 10.1128/aem.01107-19] [Citation(s) in RCA: 11] [Impact Index Per Article: 2.2] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/15/2019] [Accepted: 07/21/2019] [Indexed: 01/07/2023] Open
Abstract
Salmonella enterica subsp. enterica serovar Enteritidis is able to adapt to sublethal concentrations of ethanol, which subsequently induce tolerance of this pathogen to normally lethal ethanol challenges. This work aims to elucidate the underlying ethanol adaptation mechanisms of S Enteritidis by proteomic and mutagenic analyses. The global proteomic response of S Enteritidis to ethanol adaptation (5% ethanol for 1 h) was determined by isobaric tags for relative and absolute quantification (iTRAQ), and it was found that a total of 138 proteins were differentially expressed in ethanol-adapted cells compared to nonadapted cells. A total of 56 upregulated proteins were principally associated with purine metabolism and as transporters for glycine betaine, phosphate, d-alanine, thiamine, and heme, whereas 82 downregulated proteins were mainly involved in enterobactin biosynthesis and uptake, the ribosome, flagellar assembly, and virulence. Moreover, mutagenic analysis further revealed the functions of two highly upregulated proteins belonging to purine metabolism (HiuH, 5-hydroxyisourate hydrolase) and glycine betaine transport (ProX, glycine betaine-binding periplasmic protein) pathways. Deletion of either hiuH or proX resulted in the development of a stronger ethanol tolerance response, suggesting negative regulatory roles in ethanol adaptation. Collectively, this work suggests that S Enteritidis employs multiple strategies to coordinate ethanol adaptation.IMPORTANCE Stress adaptation in foodborne pathogens has been recognized as a food safety concern since it may compromise currently employed microbial intervention strategies. While adaptation to sublethal levels of ethanol is able to induce ethanol tolerance in foodborne pathogens, the molecular mechanism underlying this phenomenon is poorly characterized. Hence, global proteomic analysis and mutagenic analysis were conducted in the current work to understand the strategies employed by Salmonella enterica subsp. enterica serovar Enteritidis to respond to ethanol adaptation. It was revealed that coordinated regulation of multiple pathways involving metabolism, ABC transporters, regulators, enterobactin biosynthesis and uptake, the ribosome, flagellar assembly, and virulence was responsible for the development of ethanol adaptation response in this pathogen. Such knowledge will undoubtedly contribute to the development and implementation of more-effective food safety interventions.
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Cross Talk between SigB and PrfA in Listeria monocytogenes Facilitates Transitions between Extra- and Intracellular Environments. Microbiol Mol Biol Rev 2019; 83:83/4/e00034-19. [PMID: 31484692 DOI: 10.1128/mmbr.00034-19] [Citation(s) in RCA: 38] [Impact Index Per Article: 7.6] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/24/2022] Open
Abstract
The foodborne pathogen Listeria monocytogenes can modulate its transcriptome and proteome to ensure its survival during transmission through vastly differing environmental conditions. While L. monocytogenes utilizes a large array of regulators to achieve survival and growth in different intra- and extrahost environments, the alternative sigma factor σB and the transcriptional activator of virulence genes protein PrfA are two key transcriptional regulators essential for responding to environmental stress conditions and for host infection. Importantly, emerging evidence suggests that the shift from extrahost environments to the host gastrointestinal tract and, subsequently, to intracellular environments requires regulatory interplay between σB and PrfA at transcriptional, posttranscriptional, and protein activity levels. Here, we review the current evidence for cross talk and interplay between σB and PrfA and their respective regulons and highlight the plasticity of σB and PrfA cross talk and the role of this cross talk in facilitating successful transition of L. monocytogenes from diverse extrahost to diverse extra- and intracellular host environments.
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Oh E, Andrews KJ, McMullen LM, Jeon B. Tolerance to stress conditions associated with food safety in Campylobacter jejuni strains isolated from retail raw chicken. Sci Rep 2019; 9:11915. [PMID: 31417115 PMCID: PMC6695378 DOI: 10.1038/s41598-019-48373-0] [Citation(s) in RCA: 19] [Impact Index Per Article: 3.8] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/28/2018] [Accepted: 07/30/2019] [Indexed: 12/15/2022] Open
Abstract
Campylobacter jejuni is a microaerophilic foodborne pathogen that is sensitive to stress conditions. However, it is not yet understood how this stress-sensitive pathogen may cause a significant number of cases of human gastroenteritis worldwide. In this study, we examined stress tolerance in 70 C. jejuni strains isolated from retail chicken under several stress conditions related to food safety. Compared to oxygen-sensitive (OS) strains of C. jejuni, C. jejuni strains with increased aerotolerance, such as hyper-aerotolerant (HAT) and aerotolerant (AT) strains, were more tolerant to peracetic acid, refrigeration and freeze-thaw stresses. However, the levels of thermotolerance and hyper-osmotolerance were not associated with the aerotolerance level of C. jejuni. The HAT and AT strains of C. jejuni exhibited significantly increased activities of catalase and superoxide dismutase (SOD), compared to the OS strains. Consistently, the HAT and AT strains were highly tolerant to oxidants, such as hydrogen peroxide, cumene hydroperoxide and menadione, compared to the OS strains. The AT and HAT strains that were tolerant to stresses, particularly peracetic acid and refrigeration, predominantly belonged to multilocus sequence typing (MLST) clonal complex (CC)-21. This study shows that oxidative stress resistance plays a role in determining the differential level of aerotolerance in C. jejuni and that AT and HAT strains of C. jejuni are more tolerant to oxidants and low temperatures than OS strains.
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Affiliation(s)
- Euna Oh
- School of Public Health, University of Alberta, Edmonton, Alberta, Canada
| | - Katelyn J Andrews
- School of Public Health, University of Alberta, Edmonton, Alberta, Canada
| | - Lynn M McMullen
- Department of Agricultural, Food and Nutritional Science, University of Alberta, Edmonton, AB, Canada
| | - Byeonghwa Jeon
- School of Public Health, University of Alberta, Edmonton, Alberta, Canada.
- Environmental Health Sciences, School of Public Health, University of Minnesota, St. Paul, MN, USA.
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Kiatsomphob S, Taniguchi T, Tarigan E, Latt KM, Jeon B, Misawa N. Aerotolerance and multilocus sequence typing among Campylobacter jejuni strains isolated from humans, broiler chickens, and cattle in Miyazaki Prefecture, Japan. J Vet Med Sci 2019; 81:1144-1151. [PMID: 31270309 PMCID: PMC6715926 DOI: 10.1292/jvms.19-0228] [Citation(s) in RCA: 8] [Impact Index Per Article: 1.6] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/28/2022] Open
Abstract
Campylobacter jejuni is one of the leading causes of human gastroenteritis in Japan. As chickens and cattle are common reservoirs for C. jejuni, this microaerophilic, stress-sensitive bacterium can overcome and survive various stress conditions during zoonotic transmission, particularly foodborne, to humans. How C. jejuni overcomes stress conditions is, however, unclear. In the present study, 70 C. jejuni strains isolated from various sources (26 human, 20 broilers, and 24 cattle isolates) in Miyazaki, Japan, from 2010 to 2012, were subjected to multilocus sequence typing (MLST) and aerotolerance testing (aerobic shaking at 200 rpm). The results demonstrated that C. jejuni strains from Miyazaki belonged to 12 clonal complexes (CCs) and 43 sequence types (STs). CC-21 and CC-460 were mainly detected in human clinical strains. Most tested strains were aerotolerant, and only one (1.4%) was deemed sensitive to aerobic stress. Approximately 40% strains survived the 24-hr vigorous aerobic shaking at 200 rpm, and these hyper-aerotolerant strains were more prevalent in broiler and cattle isolates than in human isolates. Phylogenetic analysis divided the strains into five clusters, each showing a different pattern of host association. Thus, we have demonstrated for the first time that C. jejuni strains with increased tolerance to aerobic stress are highly prevalent in broilers and cattle in Miyazaki, Japan, and that certain clonal populations are frequently implicated in human infection in this area.
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Affiliation(s)
- Savek Kiatsomphob
- Graduate School of Medicine and Veterinary Medicine, University of Miyazaki, 5200 Kihara-kiyotakecho, Miyazaki 889-1692, Japan.,Laboratory of Veterinary Public Health, Department of Veterinary Medical Science, Faculty of Agriculture, University of Miyazaki, 1-1 Gakuenkibanadai-nishi, Miyazaki 889-2192, Japan
| | - Takako Taniguchi
- Center for Animal Disease Control, University of Miyazaki, 1-1 Gakuenkibanadai-nishi, Miyazaki 889-2192, Japan
| | - Elpita Tarigan
- Center for Animal Disease Control, University of Miyazaki, 1-1 Gakuenkibanadai-nishi, Miyazaki 889-2192, Japan
| | - Khin Maung Latt
- Laboratory of Veterinary Public Health, Department of Veterinary Medical Science, Faculty of Agriculture, University of Miyazaki, 1-1 Gakuenkibanadai-nishi, Miyazaki 889-2192, Japan
| | - Byeonghwa Jeon
- School of Public Health, University of Alberta, Edmonton, AB, T6G 1C9, Canada
| | - Naoaki Misawa
- Laboratory of Veterinary Public Health, Department of Veterinary Medical Science, Faculty of Agriculture, University of Miyazaki, 1-1 Gakuenkibanadai-nishi, Miyazaki 889-2192, Japan.,Center for Animal Disease Control, University of Miyazaki, 1-1 Gakuenkibanadai-nishi, Miyazaki 889-2192, Japan
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Muchaamba F, Eshwar AK, Stevens MJA, von Ah U, Tasara T. Variable Carbon Source Utilization, Stress Resistance, and Virulence Profiles Among Listeria monocytogenes Strains Responsible for Listeriosis Outbreaks in Switzerland. Front Microbiol 2019; 10:957. [PMID: 31130938 PMCID: PMC6510287 DOI: 10.3389/fmicb.2019.00957] [Citation(s) in RCA: 17] [Impact Index Per Article: 3.4] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/01/2019] [Accepted: 04/16/2019] [Indexed: 12/21/2022] Open
Abstract
A combination of phenotype microarrays, targeted stress resistance and virulence assays and comparative genome analysis was used to compare a set of Listeria monocytogenes strains including those involved in previous Swiss foodborne listeriosis outbreaks. Despite being highly syntenic in gene content these strains showed significant phenotypic variation in utilization of different carbon (C)-sources as well as in resistance of osmotic and pH stress conditions that are relevant to host and food associated environments. An outbreak strain from the 2005 Swiss Tomme cheese listeriosis outbreak (Lm3163) showed the highest versatility in C-sources utilized whereas the strain responsible for the 1983 to 1987 Vacherin Montd'or cheese listeriosis outbreak (LL195) showed the highest tolerance to both osmotic and pH stress conditions among the examined strains. Inclusion of L-norvaline led to enhanced resistance of acidic stress in all the examined strains and there were strain-strain-specific differences observed in the ability of other amino acids and urea to enhance acid stress resistance in L. monocytogenes. A strain dependent inhibition pattern was also observed upon inclusion of β-phenylethylamine under alkaline stress conditions. In targeted phenotypic analysis the strain-specific differences in salt stress tolerance uncovered in phenotypic microarrays were corroborated and variations in host cell invasion and virulence among the examined strains were also revealed. Outbreak associated strains representing lineage I serotype 4b showed superior pathogenicity in a zebrafish infection model whilst Lm3163 a lineage II serotype 1/2a outbreak strain demonstrated the highest cellular invasion capacity amongst the tested strains. A genome wide sequence comparison of the strains only revealed few genetic differences between the strains suggesting that variations in gene regulation and expression are largely responsible for the phenotypic differences revealed among the examined strains. Our results have generated data that provides a potential basis for the future design of improved Listeria specific media to enhance routine detection and isolation of this pathogen as well as provide knowledge for developing novel methods for its control in food.
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Affiliation(s)
- Francis Muchaamba
- Institute for Food Safety and Hygiene, Vetsuisse Faculty, University of Zürich, Zurich, Switzerland
| | - Athmanya K. Eshwar
- Institute for Food Safety and Hygiene, Vetsuisse Faculty, University of Zürich, Zurich, Switzerland
| | - Marc J. A. Stevens
- Institute for Food Safety and Hygiene, Vetsuisse Faculty, University of Zürich, Zurich, Switzerland
| | | | - Taurai Tasara
- Institute for Food Safety and Hygiene, Vetsuisse Faculty, University of Zürich, Zurich, Switzerland
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59
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Oh E, Chui L, Bae J, Li V, Ma A, Mutschall SK, Taboada EN, McMullen LM, Jeon B. Frequent Implication of Multistress-Tolerant Campylobacter jejuni in Human Infections. Emerg Infect Dis 2019; 24:1037-1044. [PMID: 29774830 PMCID: PMC6004869 DOI: 10.3201/eid2406.171587] [Citation(s) in RCA: 28] [Impact Index Per Article: 5.6] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/19/2022] Open
Abstract
Campylobacter jejuni, a major cause of bacterial foodborne illnesses, is considered highly susceptible to environmental stresses. In this study, we extensively investigated the stress tolerance of 121 clinical strains of C. jejuni against 5 stress conditions (aerobic stress, disinfectant exposure, freeze-thaw, heat treatment, and osmotic stress) that this pathogenic bacterium might encounter during foodborne transmission to humans. In contrast to our current perception about high stress sensitivity of C. jejuni, a number of clinical strains of C. jejuni were highly tolerant to multiple stresses. We performed population genetics analysis by using comparative genomic fingerprinting and showed that multistress-tolerant strains of C. jejuni constituted distinct clades. The comparative genomic fingerprinting subtypes belonging to multistress-tolerant clades were more frequently implicated in human infections than those in stress-sensitive clades. We identified unique stress-tolerant C. jejuni clones and showed the role of stress tolerance in human campylobacteriosis.
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60
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Song X, Sun Y, Zhang Q, Yang X, Zheng F, He S, Wang Y. Failure of Staphylococcus aureus to Acquire Direct and Cross Tolerance after Habituation to Cinnamon Essential Oil. Microorganisms 2019; 7:E18. [PMID: 30641977 PMCID: PMC6352263 DOI: 10.3390/microorganisms7010018] [Citation(s) in RCA: 8] [Impact Index Per Article: 1.6] [Reference Citation Analysis] [Abstract] [Key Words] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/13/2018] [Revised: 01/06/2019] [Accepted: 01/08/2019] [Indexed: 11/16/2022] Open
Abstract
Utilization of sublethal concentrations of cinnamon essential oil (CEO) for food preservation has been proposed. However, exposure to stressful, sublethal growth conditions may induce bacterial tolerance to homologous or heterologous stressing agents. Hence, the ability of CEO to stimulate bacterial stress response was evaluated in the current work. Staphylococcus aureus was exposed to 1/4 and 1/2 of the minimum inhibitory concentration (MIC, 500 μL/L) of CEO for 18 h. It was found that overnight habituation to CEO failed to induce direct tolerance and cross-tolerance to lactic acid (pH 4.5), NaCl (10 g/100 mL) and high temperature (45 °C) in S. aureus. Likewise, S. aureus cells subjected to successive habituation with increasing amounts (1/16 MIC to 2× MIC) of CEO developed no direct tolerance. Taken together, CEO has no inductive effect on the acquisition of stress tolerance in S. aureus.
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Affiliation(s)
- Xiaoqiu Song
- School of Perfume and Aroma Technology, Shanghai Institute of Technology, Haiquan Road 100, Shanghai 201418, China.
| | - Yue Sun
- School of Perfume and Aroma Technology, Shanghai Institute of Technology, Haiquan Road 100, Shanghai 201418, China.
| | - Qian Zhang
- School of Perfume and Aroma Technology, Shanghai Institute of Technology, Haiquan Road 100, Shanghai 201418, China.
| | - Xiaobo Yang
- School of Perfume and Aroma Technology, Shanghai Institute of Technology, Haiquan Road 100, Shanghai 201418, China.
| | - Feng Zheng
- School of Perfume and Aroma Technology, Shanghai Institute of Technology, Haiquan Road 100, Shanghai 201418, China.
| | - Shoukui He
- School of Perfume and Aroma Technology, Shanghai Institute of Technology, Haiquan Road 100, Shanghai 201418, China.
| | - Yifei Wang
- School of Perfume and Aroma Technology, Shanghai Institute of Technology, Haiquan Road 100, Shanghai 201418, China.
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61
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Trząskowska M, Dai Y, Delaquis P, Wang S. Pathogen reduction on mung bean reduction of Escherichia coli O157:H7, Salmonella enterica and Listeria monocytogenes on mung bean using combined thermal and chemical treatments with acetic acid and hydrogen peroxide. Food Microbiol 2018; 76:62-68. [DOI: 10.1016/j.fm.2018.04.008] [Citation(s) in RCA: 14] [Impact Index Per Article: 2.3] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/28/2016] [Revised: 04/14/2018] [Accepted: 04/15/2018] [Indexed: 12/01/2022]
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62
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Lv R, Wang D, Zou M, Wang W, Ma X, Chen W, Zhou J, Ding T, Ye X, Liu D. Analysis ofBacillus cereuscell viability, sublethal injury, and death induced by mild thermal treatment. J Food Saf 2018. [DOI: 10.1111/jfs.12581] [Citation(s) in RCA: 10] [Impact Index Per Article: 1.7] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/05/2023]
Affiliation(s)
- Ruiling Lv
- College of Biosystems Engineering and Food ScienceZhejiang University Zhejiang Hangzhou China
| | - Danli Wang
- College of Biosystems Engineering and Food ScienceZhejiang University Zhejiang Hangzhou China
| | - Mingming Zou
- College of Biosystems Engineering and Food ScienceZhejiang University Zhejiang Hangzhou China
| | - Wenjun Wang
- College of Biosystems Engineering and Food ScienceZhejiang University Zhejiang Hangzhou China
| | - Xiaobin Ma
- College of Biosystems Engineering and Food ScienceZhejiang University Zhejiang Hangzhou China
| | - Weijun Chen
- College of Biosystems Engineering and Food ScienceZhejiang University Zhejiang Hangzhou China
| | - Jianwei Zhou
- College of Biosystems Engineering and Food ScienceZhejiang University Zhejiang Hangzhou China
| | - Tian Ding
- College of Biosystems Engineering and Food ScienceZhejiang University Zhejiang Hangzhou China
- Zhejiang Key Laboratory for Agro‐Food ProcessingZhejiang R&D Center for Food Technology and Equipment Zhejiang Hangzhou China
| | - Xingqian Ye
- College of Biosystems Engineering and Food ScienceZhejiang University Zhejiang Hangzhou China
- Zhejiang Key Laboratory for Agro‐Food ProcessingZhejiang R&D Center for Food Technology and Equipment Zhejiang Hangzhou China
| | - Donghong Liu
- College of Biosystems Engineering and Food ScienceZhejiang University Zhejiang Hangzhou China
- Zhejiang Key Laboratory for Agro‐Food ProcessingZhejiang R&D Center for Food Technology and Equipment Zhejiang Hangzhou China
- Fuli Institute of Food ScienceZhejiang University Zhejiang Hangzhou China
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63
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Siddiqee MH, Henry R, Coulthard R, Schang C, Williamson R, Coleman R, Rooney G, Deletic A, McCarthy D. Salmonella enterica Serovar Typhimurium and Escherichia coli Survival in Estuarine Bank Sediments. INTERNATIONAL JOURNAL OF ENVIRONMENTAL RESEARCH AND PUBLIC HEALTH 2018; 15:E2597. [PMID: 30469325 PMCID: PMC6266694 DOI: 10.3390/ijerph15112597] [Citation(s) in RCA: 2] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Download PDF] [Figures] [Subscribe] [Scholar Register] [Received: 10/02/2018] [Revised: 11/07/2018] [Accepted: 11/14/2018] [Indexed: 11/16/2022]
Abstract
Estuarine bank sediments have the potential to support the survival and growth of fecal indicator organisms, including Escherichia coli. However, survival of fecal pathogens in estuarine sediments is not well researched and therefore remains a significant knowledge gap regarding public health risks in estuaries. In this study, simultaneous survival of Escherichia coli and a fecal pathogen, Salmonella enterica serovar Typhimurium, was studied for 21 days in estuarine bank sediment microcosms. Observed growth patterns for both organisms were comparable under four simulated scenarios; for continuous-desiccation, extended-desiccation, periodic-inundation, and continuous-inundation systems, logarithmic decay coefficients were 1.54/day, 1.51/day, 0.14/day, and 0.20/day, respectively, for E. coli, and 1.72/day, 1.64/day, 0.21/day, and 0.24/day for S. Typhimurium. Re-wetting of continuous-desiccated systems resulted in potential re-growth, suggesting survival under moisture-limited conditions. Key findings from this study include: (i) Bank sediments can potentially support human pathogens (S. Typhimurium), (ii) inundation levels influence the survival of fecal bacteria in estuarine bank sediments, and (iii) comparable survival rates of S. Typhimurium and E. coli implies the latter could be a reliable fecal indicator in urban estuaries. The results from this study will help select suitable monitoring and management strategies for safer recreational activities in urban estuaries.
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Affiliation(s)
- Mahbubul H Siddiqee
- Environmental and Public Health Microbiology Laboratory (EPHM LAB), Department of Civil Engineering, Monash University, Melbourne, VIC-3168, Australia.
- Molecular and Environmental Microbiology Laboratory (MEM LAB), Department of Mathematics and Natural Sciences, BRAC University, Dhaka 1212, Bangladesh.
| | - Rebekah Henry
- Environmental and Public Health Microbiology Laboratory (EPHM LAB), Department of Civil Engineering, Monash University, Melbourne, VIC-3168, Australia.
| | - Rebecca Coulthard
- Environmental and Public Health Microbiology Laboratory (EPHM LAB), Department of Civil Engineering, Monash University, Melbourne, VIC-3168, Australia.
| | - Christelle Schang
- Environmental and Public Health Microbiology Laboratory (EPHM LAB), Department of Civil Engineering, Monash University, Melbourne, VIC-3168, Australia.
| | - Richard Williamson
- Environmental and Public Health Microbiology Laboratory (EPHM LAB), Department of Civil Engineering, Monash University, Melbourne, VIC-3168, Australia.
| | - Rhys Coleman
- Melbourne Water Corporation, Docklands, VIC-3008, Australia.
| | - Graham Rooney
- Melbourne Water Corporation, Docklands, VIC-3008, Australia.
| | - Ana Deletic
- Environmental and Public Health Microbiology Laboratory (EPHM LAB), Department of Civil Engineering, Monash University, Melbourne, VIC-3168, Australia.
| | - David McCarthy
- Environmental and Public Health Microbiology Laboratory (EPHM LAB), Department of Civil Engineering, Monash University, Melbourne, VIC-3168, Australia.
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Pirone-Davies C, Chen Y, Pightling A, Ryan G, Wang Y, Yao K, Hoffmann M, Allard MW. Genes significantly associated with lineage II food isolates of Listeria monocytogenes. BMC Genomics 2018; 19:708. [PMID: 30253738 PMCID: PMC6157050 DOI: 10.1186/s12864-018-5074-2] [Citation(s) in RCA: 28] [Impact Index Per Article: 4.7] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/24/2018] [Accepted: 09/12/2018] [Indexed: 01/02/2023] Open
Abstract
Background Listeria monocytogenes is a widespread foodborne pathogen that can cause listeriosis, a potentially fatal infection. L. monocytogenes is subdivided into four phylogenetic lineages, with the highest incidence of listeriosis occurring within lineage I followed by lineage II. Strains of L. monocytogenes differ in their phenotypic characteristics, including virulence. However, the genetic bases for these observed differences are not well understood, and current efforts to monitor L. monocytogenes in food consider all strains to be equally virulent. We use a comparative genomics approach to identify genes and single nucleotide polymorphisms (SNPs) in 174 clinical and food isolates of L. monocytogenes that potentially contribute to virulence or the capacity to adapt to food environments. Results No SNPs are significantly associated with food or clinical isolates. No genes are significantly associated with food or clinical isolates from lineage I, but eight genes consisting of multiple homologues are associated with lineage II food isolates. These include three genes which encode hypothetical proteins, the cadmium resistance genes cadA and cadC, the multi-drug resistance gene ebrB, a quaternary ammonium compound resistance gene qac, and a regulatory gene. All eight genes are plasmid-borne, and most closed L. monocytogenes plasmids carry at least five of the genes (24/27). In addition, plasmids are more frequently associated with lineage II food isolates than with lineage II clinical isolates. Conclusions We identify eight genes that are significantly associated with food isolates in lineage II. Interestingly, the eight genes are virtually absent in lineage II outbreak isolates, are composed of homologues which show a nonrandom distribution among lineage I serotypes, and the sequences are highly conserved across 27 closed Listeria plasmids. The functions of these genes should be explored further and will contribute to our understanding of how L. monocytogenes adapts to the host and food environments. Moreover, these genes may also be useful as markers for risk assessment models of either pathogenicity or the ability to proliferate in food and the food processing environment. Electronic supplementary material The online version of this article (10.1186/s12864-018-5074-2) contains supplementary material, which is available to authorized users.
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Affiliation(s)
- Cary Pirone-Davies
- Division of Microbiology, Office of Regulatory Science, Center for Food Safety and Applied Nutrition, U.S. Food and Drug Administration, College Park, MD, USA.
| | - Yi Chen
- Division of Microbiology, Office of Regulatory Science, Center for Food Safety and Applied Nutrition, U.S. Food and Drug Administration, College Park, MD, USA
| | - Arthur Pightling
- Office of Analytics and Outreach, Center for Food Safety and Applied Nutrition, U.S. Food and Drug Administration, College Park, MD, USA
| | - Gina Ryan
- Division of Microbiology, Office of Regulatory Science, Center for Food Safety and Applied Nutrition, U.S. Food and Drug Administration, College Park, MD, USA
| | - Yu Wang
- Office of Analytics and Outreach, Center for Food Safety and Applied Nutrition, U.S. Food and Drug Administration, College Park, MD, USA
| | - Kuan Yao
- Division of Microbiology, Office of Regulatory Science, Center for Food Safety and Applied Nutrition, U.S. Food and Drug Administration, College Park, MD, USA
| | - Maria Hoffmann
- Division of Microbiology, Office of Regulatory Science, Center for Food Safety and Applied Nutrition, U.S. Food and Drug Administration, College Park, MD, USA
| | - Marc W Allard
- Division of Microbiology, Office of Regulatory Science, Center for Food Safety and Applied Nutrition, U.S. Food and Drug Administration, College Park, MD, USA
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Horn N, Bhunia AK. Food-Associated Stress Primes Foodborne Pathogens for the Gastrointestinal Phase of Infection. Front Microbiol 2018; 9:1962. [PMID: 30190712 PMCID: PMC6115488 DOI: 10.3389/fmicb.2018.01962] [Citation(s) in RCA: 38] [Impact Index Per Article: 6.3] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/04/2018] [Accepted: 08/02/2018] [Indexed: 12/13/2022] Open
Abstract
The incidence of foodborne outbreaks and product recalls is on the rise. The ability of the pathogen to adapt and survive under stressful environments of food processing and the host gastrointestinal tract may contribute to increasing foodborne illnesses. In the host, multiple factors such as bacteriolytic enzymes, acidic pH, bile, resident microflora, antimicrobial peptides, and innate and adaptive immune responses are essential in eliminating pathogens. Likewise, food processing and preservation techniques are employed to eliminate or reduce human pathogens load in food. However, sub-lethal processing or preservation treatments may evoke bacterial coping mechanisms that alter gene expression, specifically and broadly, resulting in resistance to the bactericidal insults. Furthermore, environmentally cued changes in gene expression can lead to changes in bacterial adhesion, colonization, invasion, and toxin production that contribute to pathogen virulence. The shared microenvironment between the food preservation techniques and the host gastrointestinal tract drives microbes to adapt to the stressful environment, resulting in enhanced virulence and infectivity during a foodborne illness episode.
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Affiliation(s)
- Nathan Horn
- Department of Animal Sciences, Purdue University, West Lafayette, IN, United States
| | - Arun K. Bhunia
- Molecular Food Microbiology Laboratory, Department of Food Science, Purdue University, West Lafayette, IN, United States
- Department of Comparative Pathobiology, Purdue University, West Lafayette, IN, United States
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66
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Faour-Klingbeil D, Todd ECD. The inhibitory effect of traditional pomegranate molasses onS. typhimuriumgrowth on parsley leaves and in mixed salad vegetables. J Food Saf 2018. [DOI: 10.1111/jfs.12469] [Citation(s) in RCA: 7] [Impact Index Per Article: 1.2] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/30/2022]
Affiliation(s)
| | - Ewen C. D. Todd
- Department of Nutrition and Food Science; American University of Beirut; Beirut Lebanon
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Akgul A, Akgul A, Lawrence ML, Karsi A. Stress-related genes promote Edwardsiella ictaluri pathogenesis. PLoS One 2018; 13:e0194669. [PMID: 29554143 PMCID: PMC5858854 DOI: 10.1371/journal.pone.0194669] [Citation(s) in RCA: 8] [Impact Index Per Article: 1.3] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/28/2017] [Accepted: 03/07/2018] [Indexed: 12/22/2022] Open
Abstract
Edwardsiella ictaluri is a Gram-negative facultative anaerobic rod and the causative agent of enteric septicemia of channel catfish (ESC), which is one of the most prevalent diseases of catfish, causing significant economic losses in the catfish industry. E. ictaluri is resistant to complement system and macrophage killing, which results in rapid systemic septicemia. However, mechanisms of E. ictaluri stress responses under conditions of host environment are not studied well. Therefore, in this work, we report E. ictaluri stress responses during hydrogen peroxide, low pH, and catfish serum stresses as well as during catfish invasion. E. ictaluri stress responses were characterized by identifying expression of 13 universal stress protein (USP) genes (usp01-usp13) and seven USP-interacting protein genes (groEL, groES, dnaK, grpE, and clpB, grpE, relA). Data indicated that three usp genes (usp05, usp07, and usp13) were highly expressed in all stress conditions. Similarly, E. ictaluri heat shock proteins groEL, groES, dnaK, grpE, and clpB were highly expressed in oxidative stress. Also, E. ictaluri grpE and relA were highly expressed in catfish spleen and head kidney. These findings contribute to our understanding of stress response mechanisms in E. ictaluri stress response, and stress-related proteins that are essential for E. ictaluri could be potential targets for live attenuated vaccine development against ESC.
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Affiliation(s)
- Ali Akgul
- Department of Basic Sciences, College of Veterinary Medicine, Mississippi State University, Mississippi State, MS, United States of America
| | - Ayfer Akgul
- Department of Clinical Sciences, College of Veterinary Medicine, Mississippi State University, Mississippi State, MS, United States of America
| | - Mark L. Lawrence
- Department of Basic Sciences, College of Veterinary Medicine, Mississippi State University, Mississippi State, MS, United States of America
| | - Attila Karsi
- Department of Basic Sciences, College of Veterinary Medicine, Mississippi State University, Mississippi State, MS, United States of America
- * E-mail:
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68
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Ananda AP, Manukumar HM, Umesha S, Soumya G, Priyanka D, Mohan Kumar AS, Krishnamurthy NB, Savitha KR. A Relook at Food Packaging for Cost Effective by Incorporation of Novel Technologies. ACTA ACUST UNITED AC 2017. [DOI: 10.1007/s41783-017-0011-4] [Citation(s) in RCA: 7] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/16/2022]
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69
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Sihto HM, Stephan R, Engl C, Chen J, Johler S. Effect of food-related stress conditions and loss of agr and sigB on seb promoter activity in S. aureus. Food Microbiol 2017; 65:205-212. [PMID: 28400004 DOI: 10.1016/j.fm.2017.03.006] [Citation(s) in RCA: 8] [Impact Index Per Article: 1.1] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/01/2016] [Revised: 02/01/2017] [Accepted: 03/06/2017] [Indexed: 10/20/2022]
Abstract
Staphylococcal enterotoxin B (SEB) causes staphylococcal food poisoning and is produced in up to ten times higher quantities than other major enterotoxins. While Staphylococcus aureus growth is often repressed by competing flora, the organism exhibits a decisive growth advantage under some stress conditions. So far, data on the influence of food-related stressors and regulatory mutations on seb expression is limited and largely based on laboratory strains, which were later reported to harbor mutations. Therefore, the aim of this study was to investigate the influence of stress and regulatory mutations on seb promoter activity. To this end, transcriptional fusions were created in two strains, USA300 and HG003, carrying different seb upstream sequences fused to a blaZ reporter. NaCl, nitrite, and glucose stress led to significantly decreased seb promoter activity, while lactic acid stress resulted in significantly increased seb promoter activity. Loss of agr decreased seb promoter activity and loss of sigB increased promoter activity, with the magnitude of change depending on the strain. These results demonstrate that mild stress conditions encountered during food production and preservation can induce significant changes in seb promoter activity.
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Affiliation(s)
- Henna-Maria Sihto
- Institute for Food Safety and Hygiene, University of Zurich, Zurich, Switzerland
| | - Roger Stephan
- Institute for Food Safety and Hygiene, University of Zurich, Zurich, Switzerland
| | - Christoph Engl
- Skirball Institute of Biomolecular Medicine, New York University Medical Center New York, New York, USA
| | - John Chen
- Department of Microbiology and Immunology, Yong Loo Lin School of Medicine, National University of Singapore, 5 Science Drive 2, Singapore, Singapore
| | - Sophia Johler
- Institute for Food Safety and Hygiene, University of Zurich, Zurich, Switzerland; Skirball Institute of Biomolecular Medicine, New York University Medical Center New York, New York, USA.
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70
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Oliveira AR, Domingues FC, Ferreira S. The influence of resveratrol adaptation on resistance to antibiotics, benzalkonium chloride, heat and acid stresses of Staphylococcus aureus and Listeria monocytogenes. Food Control 2017. [DOI: 10.1016/j.foodcont.2016.11.011] [Citation(s) in RCA: 10] [Impact Index Per Article: 1.4] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/23/2023]
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71
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Tremonte P, Succi M, Coppola R, Sorrentino E, Tipaldi L, Picariello G, Pannella G, Fraternali F. Homology-Based Modeling of Universal Stress Protein from Listeria innocua Up-Regulated under Acid Stress Conditions. Front Microbiol 2016; 7:1998. [PMID: 28066336 PMCID: PMC5168468 DOI: 10.3389/fmicb.2016.01998] [Citation(s) in RCA: 18] [Impact Index Per Article: 2.3] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/10/2016] [Accepted: 11/29/2016] [Indexed: 01/31/2023] Open
Abstract
An Universal Stress Protein (USP) expressed under acid stress condition by Listeria innocua ATCC 33090 was investigated. The USP was up-regulated not only in the stationary phase but also during the exponential growth phase. The three dimensional (3D) structure of USP was predicted using a combined proteomic and bioinformatics approach. Phylogenetic analysis showed that the USP from Listeria detected in our study was distant from the USPs of other bacteria (such as Pseudomonas spp., Escherichia coli, Salmonella spp.) and clustered in a separate and heterogeneous class including several USPs from Listeria spp. and Lactobacillus spp. An important information on the studied USP was obtained from the 3D-structure established through the homology modeling procedure. In detail, the Model_USP-691 suggested that the investigated USP had a homo-tetrameric quaternary structure. Each monomer presented an architecture analogous to the Rossmann-like α/β-fold with five parallel β-strands, and four α-helices. The analysis of monomer-monomer interfaces and quality of the structure alignments confirmed the model reliability. In fact, the structurally and sequentially conserved hydrophobic residues of the β-strand 5 (in particular the residues V146 and V148) were involved in the inter-chains contact. Moreover, the highly conserved residues I139 and H141 in the region α4 were involved in the dimer association and functioned as hot spots into monomer–monomer interface assembly. The hypothetical assembly of dimers was also supported by the large interface area and by the negative value of solvation free energy gain upon interface interaction. Finally, the structurally conserved ATP-binding motif G-2X-G-9X-G(S/T-N) suggested for a putative role of ATP in stabilizing the tetrameric assembly of the USP. Therefore, the results obtained from a multiple approach, consisting in the application of kinetic, proteomic, phylogenetic and modeling analyses, suggest that Listeria USP could be considered a new type of ATP-binding USP involved in the response to acid stress condition during the exponential growth phase.
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Affiliation(s)
- Patrizio Tremonte
- Department of Agricultural, Environmental and Food Sciences (DiAAA), University of Molise Campobasso, Italy
| | - Mariantonietta Succi
- Department of Agricultural, Environmental and Food Sciences (DiAAA), University of Molise Campobasso, Italy
| | - Raffaele Coppola
- Department of Agricultural, Environmental and Food Sciences (DiAAA), University of Molise Campobasso, Italy
| | - Elena Sorrentino
- Department of Agricultural, Environmental and Food Sciences (DiAAA), University of Molise Campobasso, Italy
| | - Luca Tipaldi
- Department of Agricultural, Environmental and Food Sciences (DiAAA), University of Molise Campobasso, Italy
| | - Gianluca Picariello
- Institute of Food Science, National Research Council (ISA-CNR) Avellino, Italy
| | - Gianfranco Pannella
- Department of Agricultural, Environmental and Food Sciences (DiAAA), University of Molise Campobasso, Italy
| | - Franca Fraternali
- Randall Division of Cellular and Molecular Biophysics, New Hunt's House King's College London, UK
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72
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Kennedy NM, Mukherjee N, Banerjee P. Escherichia coli O157:H7 Cells Exposed to Lettuce Leaf Lysate in Refrigerated Conditions Exhibit Differential Expression of Selected Virulence and Adhesion-Related Genes with Altered Mammalian Cell Adherence. J Food Prot 2016; 79:1259-65. [PMID: 27357048 DOI: 10.4315/0362-028x.jfp-15-504] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.1] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/11/2022]
Abstract
Contamination by and persistence of pathogenic bacteria in ready-to-eat produce have emerged as significant food safety and public health concerns. Viable produceborne pathogens cope with several stresses (e.g., temperature fluctuations and lowtemperature storage) during production and storage of the commodities. In this study, we investigated the impact of transient cold shock on Escherichia coli O157:H7 (EcO157) cells in a produce matrix (romaine lettuce leaf lysate). EcO157 cells were exposed to 25°C for 1 h, 4°C for 1 h, and 4°C for 10 min in lettuce lysate. The expression of selected genes coding for virulence, stress response, and heat and cold shock proteins was quantified by real-time quantitative reverse transcription PCR assay. Treated EcO157 cells adhered to MAC-T mammalian cells were enumerated by in vitro bioassay. Expression of the Shiga toxin 1 gene (stx1a) was upregulated significantly (P < 0.05) upon cold shock treatments, but virulence genes related to EcO157 attachment (eaeA, lpfA, and hcpA) were down-regulated. Two key members of the cold shock regulon, cold shock protein (cspA) and gyrA, were significantly induced (P < 0.05) at the refrigeration temperature (4°C). Significant upregulation of an SOS response gene, recA, was also observed. E. coli heat shock regulon member grpE was induced, but a universal stress protein (uspA) was downregulated at the refrigeration temperatures in lettuce lysate. The adhesion assay revealed a temperature-dependent reduction in the attachment of cold-shocked EcO157 cells. The results of the current study indicate a reduction in the attachment of cold-shocked EcO157 to epithelial cells and higher levels of Shiga toxin gene expression at the molecular level.
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Affiliation(s)
- Nicole M Kennedy
- Department of Food and Animal Sciences, Alabama A&M University, Huntsville, Alabama 35762, USA
| | - Nabanita Mukherjee
- Division of Epidemiology, Biostatistics, and Environmental Health, School of Public Health, University of Memphis, Memphis, Tennessee 38152, USA
| | - Pratik Banerjee
- Department of Food and Animal Sciences, Alabama A&M University, Huntsville, Alabama 35762, USA; Division of Epidemiology, Biostatistics, and Environmental Health, School of Public Health, University of Memphis, Memphis, Tennessee 38152, USA.
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73
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Nagar V, Bandekar JR, Shashidhar R. Expression of virulence and stress response genes in Aeromonas hydrophila under various stress conditions. J Basic Microbiol 2016; 56:1132-1137. [PMID: 27163835 DOI: 10.1002/jobm.201600107] [Citation(s) in RCA: 7] [Impact Index Per Article: 0.9] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/24/2016] [Accepted: 04/19/2016] [Indexed: 11/10/2022]
Abstract
Aeromonas hydrophila has emerged as an important human pathogen as it causes gastroenteritis and extra-intestinal infections. Information regarding the influence of environmental stresses on gene expression profile of A. hydrophila is lacking. The impact of nutrient replenishment, nutrient deprivation, acid stress, and cold shock on housekeeping, general stress-response, and virulence genes was studied using quantitative real-time PCR in two A. hydrophila strains, CECT 839T , and A331. These sub-lethal stresses invoked significant changes in the expression of these genes in a strain-dependent manner. Overall, nutrient replenishment and deprivation significantly induced the expression of housekeeping (rpoD), general stress regulators (uspA and rpoS), and virulence (aer) genes, indicating their importance in regulating the survival and virulence of A. hydrophila under these stress conditions. rpoS gene was significantly induced under cold shock; whereas, acid stress significantly induced the expression of uspA gene. This is the first study to investigate the effect of environmental parameters on the expression of stress-response and virulence genes in A. hydrophila strains.
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Affiliation(s)
- Vandan Nagar
- Food Technology Division, Bhabha Atomic Research Centre, Mumbai, India.
| | - Jayant R Bandekar
- Food Technology Division, Bhabha Atomic Research Centre, Mumbai, India
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74
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Greppi A, Rantsiou K. Methodological advancements in foodborne pathogen determination: from presence to behavior. Curr Opin Food Sci 2016. [DOI: 10.1016/j.cofs.2016.04.005] [Citation(s) in RCA: 7] [Impact Index Per Article: 0.9] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/15/2022]
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75
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Abee T, Koomen J, Metselaar K, Zwietering M, den Besten H. Impact of Pathogen Population Heterogeneity and Stress-Resistant Variants on Food Safety. Annu Rev Food Sci Technol 2016; 7:439-56. [DOI: 10.1146/annurev-food-041715-033128] [Citation(s) in RCA: 27] [Impact Index Per Article: 3.4] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/09/2022]
Affiliation(s)
- T. Abee
- Laboratory of Food Microbiology, Wageningen University, 6700 AA Wageningen, The Netherlands;
| | - J. Koomen
- Laboratory of Food Microbiology, Wageningen University, 6700 AA Wageningen, The Netherlands;
| | - K.I. Metselaar
- Laboratory of Food Microbiology, Wageningen University, 6700 AA Wageningen, The Netherlands;
| | - M.H. Zwietering
- Laboratory of Food Microbiology, Wageningen University, 6700 AA Wageningen, The Netherlands;
| | - H.M.W. den Besten
- Laboratory of Food Microbiology, Wageningen University, 6700 AA Wageningen, The Netherlands;
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76
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Yadav A, Saxena G, Saxena V, Kataria J. Study on Heat Stress Response in Salmonella Typhimurium and Salmonella Enteritidis and its Impact on their Attachment to Dressed Broiler Skin Surface. ACTA ACUST UNITED AC 2016. [DOI: 10.3923/ajava.2016.114.121] [Citation(s) in RCA: 11] [Impact Index Per Article: 1.4] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/15/2022]
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77
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Impact of Moderate Heat, Carvacrol, and Thymol Treatments on the Viability, Injury, and Stress Response of Listeria monocytogenes. BIOMED RESEARCH INTERNATIONAL 2015; 2015:548930. [PMID: 26539510 PMCID: PMC4619816 DOI: 10.1155/2015/548930] [Citation(s) in RCA: 16] [Impact Index Per Article: 1.8] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Subscribe] [Scholar Register] [Received: 04/22/2015] [Accepted: 06/11/2015] [Indexed: 11/18/2022]
Abstract
The microbial safety and stability of minimally processed foods are based on the application of combined preservative factors. Since microorganisms are able to develop adaptive networks to survive under conditions of stress, food safety may be affected, and therefore understanding of stress adaptive mechanisms plays a key role in designing safe food processing conditions. In the present study, the viability and the sublethal injury of Listeria monocytogenes exposed to moderate heat (55 °C) and/or essential oil compounds (carvacrol and thymol, 0.3 mM) treatments were studied. Synergistic effects were obtained when combining mild heat (55 °C) with one or both essential oil compounds, leading to inactivation kinetics values three to four times lower than when using heat alone. All the treatments applied caused some injury in the population. The injury levels ranged from around 20% of the surviving population under the mildest conditions to more than 99.99% under the most stringent conditions. Protein extracts of cells exposed to these treatments were analysed by two-dimensional gel electrophoresis. The results obtained revealed that stressed cells exhibited differential protein expression to control cells. The proteins upregulated under these stressing conditions were implicated, among other functions, in stress response, metabolism, and protein refolding.
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