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Microorganisms Feb 2024() is a pathogen that is transmitted through contaminated food and causes the illness known as listeriosis. The virulence factor InlA plays a crucial role in the...
() is a pathogen that is transmitted through contaminated food and causes the illness known as listeriosis. The virulence factor InlA plays a crucial role in the invasion of into the human intestinal epithelium. In addition, InlA enhances the pathogenicity of host strains, and different strains of contain varying variations of InlA. Our study analyzed a total of 4393 published genomes from 511 sequence types (STs) of diverse origins. We identified 300 unique InlA protein sequence types (PSTs) and revealed 45 highly mutated amino acid sites. The leucine-rich repeat (LRR) region was found to be the most conserved among the InlA, while the protein A (PA) region experienced the highest mutation rate. Two new types of mutations were identified in the B-repeat region of InlA. Correspondence analysis (CA) was used to analyze correlations between the lineages or 10 most common sequence types (STs) and amino acid (aa) sites. ST8 was strongly correlated with site 192_F, 454_T. ST7 exhibited a strong correlation with site 51_A, 573_E, 648_S, and 664_A, and it was also associated with ST6 and site 544_N, 671_A, 738_B, 739_B, 740_B, and 774_Y. Additionally, a strong correlation between ST1 and site 142_S, 738_N, ST2 and site 2_K, 142_S, 738_N, as well as ST87 and site2_K, 738_N was demonstrated. Our findings contribute significantly to the understanding of the distribution, composition, and conservation of InlA in These findings also suggest a potential role of InlA in supporting molecular epidemiological tracing efforts.
PubMed: 38543536
DOI: 10.3390/microorganisms12030485 -
Molecules (Basel, Switzerland) Jul 2023Microbial factors, including bacteria, viruses, and other pathogens, are significant contributors to foodborne illnesses, posing serious food safety risks due to their...
Microbial factors, including bacteria, viruses, and other pathogens, are significant contributors to foodborne illnesses, posing serious food safety risks due to their potential for rapid growth and contamination. is one of the most common types of foodborne bacteria that can cause serious foodborne diseases or even fatalities. In this study, a novel nucleic acid amplification method called Proofman-LMTIA was employed to detect contamination in food. This method combines proofreading enzyme-mediated probe cleavage with ladder-shape melting temperature isothermal amplification. A positive recombinant plasmid was used as a control to ensure the accuracy of the detection results, and primers and Proofman probes were specifically designed for the LMTIA. Genomic DNA was extracted, the reaction temperature was optimized, and the primers' specificity was verified using foodborne pathogens like Staphylococcus aureus, Escherichia coli O157:H7, and Salmonella. The sensitivity was assessed by testing serial dilutions of genomic DNA, and the method's applicability was confirmed by detecting artificially contaminated fresh pork. The established LMTIA method exhibited both high specificity and sensitivity. At the optimal reaction temperature of 63 °C, the primers specifically identified contamination in pork at a concentration of 8.0 ± 0.7 colony-forming units (CFUs) per 25 g. Furthermore, the Proofman-LMTIA method was applied to test DNA in 30 food samples purchased from a Chinese retail market, and reassuringly, all results indicated no contamination. Proofman-LMTIA can serve as a reliable and rapid method for detecting in food, contributing to public health by safeguarding consumers from foodborne illnesses, and strengthening food safety regulations.
Topics: Humans; Food Contamination; Food Microbiology; Listeria monocytogenes; Sensitivity and Specificity; Foodborne Diseases; Colony Count, Microbial
PubMed: 37513329
DOI: 10.3390/molecules28145457 -
Emerging Infectious Diseases Dec 2023Genomic data on the foodborne pathogen Listeria monocytogenes from Central America are scarce. We analyzed 92 isolates collected during 2009-2019 from different regions...
Genomic data on the foodborne pathogen Listeria monocytogenes from Central America are scarce. We analyzed 92 isolates collected during 2009-2019 from different regions in Costa Rica, compared those to publicly available genomes, and identified unrecognized outbreaks. Our findings suggest mandatory reporting of listeriosis in Costa Rica would improve pathogen surveillance.
Topics: Humans; Listeria monocytogenes; Foodborne Diseases; Costa Rica; Food Microbiology; Listeriosis; Disease Outbreaks
PubMed: 37987595
DOI: 10.3201/eid2912.230774 -
Heliyon Jul 2023Smoked salmon and smoked trout are ready-to-eat and potentially contaminated with the pathogenic bacterium making them high risk for the consumer. This raises questions...
Smoked salmon and smoked trout are ready-to-eat and potentially contaminated with the pathogenic bacterium making them high risk for the consumer. This raises questions about the presence of hypervirulent or persistent strains in the salmon and trout industries. Knowledge of the genetic diversity of circulating strains in these sectors is essential to evaluate the risk associated with this pathogen and improve food safety. We analyzed the genetic structure of 698 strains of isolated from 2006 to 2017 in France, based on their serogroup, lineage and clonal complexes (CCs) determined by Multilocus sequence typing (MLST). Most of the CCs were identified by mapping the strains PFGE profiles and a novel high-throughput real-time PCR method for CC identification. We identified thirteen CCs and one sequence type (ST) with variable distribution in salmon and trout samples (food, environment). The three most prevalent CCs were CC121, CC26 and CC204. Strains from ST191 and CC54 were detected for the first time in these sectors, while less than 0.6% of the isolates belonged to the hyper-virulent CC1, CC6 and CC20. No CC was exclusively associated with the salmon sector. This project allowed us to assess the population diversity of CCs of in the salmon and trout industries.
PubMed: 37483814
DOI: 10.1016/j.heliyon.2023.e18154 -
Food Microbiology Aug 2023Plasma-Activated Water (PAW) was generated from tap water using a surface dielectric barrier discharge at different discharge power (26 and 36 W) and activation time (5...
Plasma-Activated Water (PAW) was generated from tap water using a surface dielectric barrier discharge at different discharge power (26 and 36 W) and activation time (5 and 30 min). The inactivation of a three-strain Listeria monocytogenes cocktail in planktonic and biofilm state was evaluated. PAW generated at 36 W-30 min showed the lowest pH and the highest hydrogen peroxide, nitrates, nitrites contents and effectiveness against cells on planktonic state, resulting in 4.6 log reductions after a 15-min treatment. Although the antimicrobial activity in biofilms formed on stainless steel and on polystyrene was lower, increasing the exposure time to 30 min allowed an inactivation >4.5 log cycles. The mechanisms of action of PAW were investigated using chemical solutions that mimic its physico-chemical characteristics and also RNA-seq analysis. The main transcriptomic changes affected carbon metabolism, virulence and general stress response genes, with several overexpressed genes belonging to the cobalamin-dependent gene cluster.
Topics: Listeria monocytogenes; Transcriptome; Water; Plankton; Biofilms; Stainless Steel; Colony Count, Microbial; Food Microbiology
PubMed: 37098419
DOI: 10.1016/j.fm.2023.104252 -
Critical Reviews in Food Science and... 2024, a causative agent of listeriosis, is a major foodborne pathogen. Among pathogens, stands out for its unique ecological and physiological characteristics. This... (Review)
Review
, a causative agent of listeriosis, is a major foodborne pathogen. Among pathogens, stands out for its unique ecological and physiological characteristics. This distinct lifestyle of has a significant impact on food safety and public health, mainly through the ability of this pathogen to multiply at refrigeration temperature and to persist in the food processing environment. Due to a combination of these characteristics and emerging trends in consumer preference for ready-to-eat and minimally processed food, there is a need to develop effective and sustainable approaches to control contamination of food products with . Implementation of an efficient and reliable control strategy for must first address the problem of cross-contamination. Besides the preventive control strategies, cross-contamination may be addressed with the introduction of emerging post packaging non-thermal or thermal hurdles that can ensure delivery of a listericidal step in a packed product without interfering with the organoleptic characteristics of a food product. This review aims to present the most relevant findings underlying the distinct lifestyle of and its impact on food safety. We also discuss emerging food decontamination technologies that can be used to better control .
Topics: Humans; Listeria monocytogenes; Food Contamination; Food Microbiology; Listeriosis; Food-Processing Industry
PubMed: 36062812
DOI: 10.1080/10408398.2022.2119205 -
The Journal of Dairy Research Nov 2023Dairy products are major sources of high-quality protein and bioavailable nutrients and dairy production contributes to local, regional and national-level economies.... (Review)
Review
Dairy products are major sources of high-quality protein and bioavailable nutrients and dairy production contributes to local, regional and national-level economies. Consumption of raw milk and raw milk products does, however, carry a zoonotic risk, as does direct contact with cattle by farm husbandry staff and other employees. This review will mainly focus on the latter, and deal with it from the standpoint of a well-developed dairy industry, using the example of the Netherlands. With regard to dairy cattle, the main bacterial pathogens are spp., and as well as and . The main viral pathogens associated with dairy are Rift Valley fever virus, rabies virus, cowpox virus and vaccinia virus. The main parasitological infections are and , however, the last mentioned have mainly swimming pools as sources of human infection. Finally ectoparasites such as lice and mites and may affect employees. Some pathogens may cause health problems due to contamination. Bacterial pathogens of importance that may contaminate milk are subsp. , . Excretion of zoonotic viruses in milk is negligible in the Netherlands, and the endoparasite, is mainly found in suckling and fattening calves, whilst the risk in dairy cattle is limited. Excretion of transmissible spongiform encephalopathies (TSEs) or mycoses in milk are not expected and are, therefore, not of importance here.Being aware of the risks and working according to hygiene standards can substantially limit zoonotic risks for employees. Additionally, diseased employees are advised to limit their contact with cattle and to indicate that they work with cattle when consulting a physician. To prevent zoonotic risks through excretion of pathogens in milk, standard hygiene measures are necessary. Further, using only pasteurised milk for consumption and/or processing of milk can considerably limit the risks. If these measures are not possible, well-constructed monitoring can be followed. Monitoring programmes already exist for pathogens such as for and subsp. . For others, like programmes are not available yet as far as we know.
Topics: Cattle; Humans; Animals; Escherichia coli; Milk; Cryptosporidiosis; Cryptosporidium; Mycobacterium avium subsp. paratuberculosis; Listeria monocytogenes; Cattle Diseases
PubMed: 38186208
DOI: 10.1017/S0022029923000730 -
International Journal of Food... Aug 2023Listeria monocytogenes can adapt, persist, and form biofilms on food premises surfaces, representing a challenge for food safety, since they led to disease transmission,...
Listeria monocytogenes can adapt, persist, and form biofilms on food premises surfaces, representing a challenge for food safety, since they led to disease transmission, food contamination and spoilage during production. Physical interventions (scrubbing and wiping) can help controlling formation, nevertheless when biofilms are formed, they are usually very resistant to current control strategies used in the food industry. Biofilm attachment and formation is influenced by environment characteristics, substrate properties and microbial motility. The purpose of this study was to evaluate the ability of L. monocytogenes to attach and form biofilms on different surfaces (wood, nylon, and polycarbonate) representative of the materials used during produce harvesting and storage. Multi-strain L. monocytogenes biofilms were grown in a CDC Biofilm reactor at 20 ± 2 °C up to 96-h and characterized for: a) attachment strength by enumerating cells after rinsing; b) hydrophobicity and interfacial tension by contact angle measurements; c) biofilm architecture by Laser Scanning Confocal Microscopy. All experiments were done in triplicate. Material, incubation, and solvent significantly affected the hydrophobicity and wetting properties of L. monocytogenes biofilms (P < 0.05). The type of material and incubation time significantly influenced hydrophobicity and wetting properties of L. monocytogenes biofilms (P < 0.05). Highest contact angle and lowest interfacial tension were observed on polycarbonate coupons. The data presented contributes to understanding Listeria biofilms grow on different surfaces commonly used in produce harvesting and storage. The data obtained in this study can be used when evaluating intervention strategies to control this pathogen in food premises.
Topics: United States; Listeria monocytogenes; Food Microbiology; Biofilms; Food Contamination; Centers for Disease Control and Prevention, U.S.; Stainless Steel
PubMed: 37244228
DOI: 10.1016/j.ijfoodmicro.2023.110251 -
Frontiers in Microbiology 2023The contamination of ready to eat foods (RTE) products due to could compromise the products safety becoming a great risk for the consumers. The high presence of in RTE...
The contamination of ready to eat foods (RTE) products due to could compromise the products safety becoming a great risk for the consumers. The high presence of in RTE products has been described worldwide, but few data are available about these products from African countries. The aims of this study were to report the presence of in Zambian RTE products, providing genomic characterization and data on similarity with African circulating strains using whole genome sequencing (WGS). A total of 304 RTE products, produced by different Zambian manufacturers, were purchased at retail, from major supermarkets located in Lusaka, Zambia, comprising 130 dairy and 174 meat products. was detected only in 18 (10.3%) RTE meat products of the 174 samples tested. The MLST analysis grouped the 18 isolates in 7 clonal complexes (CCs): CC1 ( = 5), CC2 ( = 4), CC9 ( = 4), CC5 ( = 2), CC121 ( = 1), CC155 ( = 1), and CC3 ( = 1). According to the cgMLST results, several clusters were detected, in particular belonging to hyper-virulent clones CC1 and CC2. Regarding the virulence factors, a complete Pathogenicity Island 3 (LIPI-3) was present both in the CC1 and CC3, in addition to LIPI-1. Several resistance genes and mobile genetic elements were detected, including Stress Islands, the cassette and _qac transposon, plasmids and intact prophages. Despite being a first preliminary work with a limited number of samples and isolates, this study helped to increase existing knowledge on contaminated RTE products in Zambia, confirming the presence of hyper-virulent CCs, which could play an important role in human diseases, posing a public health concern for consumers.
PubMed: 37711697
DOI: 10.3389/fmicb.2023.1228726 -
International Journal of Infectious... Aug 2024Listeria monocytogenes (LM) is a health threat worldwide given its high mortality and the growing of high-risk susceptible populations.
OBJECTIVES
Listeria monocytogenes (LM) is a health threat worldwide given its high mortality and the growing of high-risk susceptible populations.
METHODS
All hospitalizations with a diagnosis of LM in the National Registry of Hospital Discharges were examined in Spain from 2000 to 2021.
RESULTS
A total of 8152 hospital admissions with LM were identified. The mean age was 59.5 years and 48% were immunosuppressed (IS). The rate of LM hospitalizations increased from 5 per 1 million population in 2000 to 8.9 in 2021 (p < 0.001). A foodborne outbreak in Andalusia determined a sharp increase in admissions with LM during 2019. The COVID-19 pandemic and lockdowns were associated with a decrease in LM admissions. The overall in-hospital mortality was 16.7%. The number of deaths in patients hospitalized with LM rose from 7.8 per 100,000 deceased in 2000 to 18 in 2021 (p < 0.001). After adjustment, age >65 years (odds ratio [OR] = 2.16), sepsis (OR = 2.60), meningoencephalitis (OR = 1.72), endocarditis (OR = 2.0), neonatal listeriosis (OR = 2.10) and IS (OR = 2.09) were associated with mortality.
CONCLUSIONS
The number of patients hospitalized with LM in Spain has increased significantly from 2000 to 2021. The increase in the rate of admissions and deaths was largely driven by the growing proportion of elderly and IS patients.
Topics: Humans; Listeriosis; Spain; Middle Aged; Male; Aged; Female; Listeria monocytogenes; Incidence; Hospital Mortality; Hospitalization; Adult; COVID-19; Aged, 80 and over; Young Adult; Adolescent; Disease Outbreaks; Child; Child, Preschool; Infant; Risk Factors
PubMed: 38734058
DOI: 10.1016/j.ijid.2024.107089