Salmonella Typhimurium Research Articles

Integrated Analysis Identifies Novel Fusion Transcripts in Laterally Spreading Tumors Suggestive of Distinct Etiology Than Colorectal Cancers.

Laterally spreading tumors (LSTs) of the colon and rectum are a class of abnormality which spreads laterally and appears ulcerated. They are a subclass of colorectal cancer (CRCs) with higher invasive potential than CRCs. Moreover, the etiology of LST still remains obscure. This study aimed to identify unique fusion transcript(s) in LSTs and evaluate their role in LST development and progression. RNA-Seq data for LST samples from the EMBL-EBI database were used to identify fusion transcripts. An integrated approach using Gene Ontology, pathway analysis, hub gene, and co-expression network analysis functionally characterized fusion transcripts to shed light upon the etiology of LSTs. We identified 48 unique fusion genes in LSTs. GO terms were enriched in mRNA metabolic (p ≤ 2.06E-06), mRNA stabilization (p ≤ 1.60E-05), in cytosol (1.20E-05), RBP (p ≤ 2.30E-04), and RNA binding activity (p ≤ 3.51E-08) processes. Pathway analysis revealed an inflammatory phenotype of LSTs suggesting a distinct etiology than CRCs as pathways were enriched in salmonella infection (p ≤ 4.41 e-03), proteoglycans in cancer (p ≤ 1.18 e-02), and insulin signaling (p ≤ 2.13 e-02). Our exclusion and inclusion criteria and hub gene analysis finally identified 9 hub genes. Co-expression analysis of hub genes identified the most significant transcription factors (NELFE, MYC, TAF1, MAX) and kinases (MAPK14, CSNK2A1, CDK1, MAPK1) which were implicated in various cancer pathways. Furthermore, an overall survival analysis of hub genes was performed. Our predefined criterion resulted in the enrichment of NPM1-PTMA (NPM1: p ≤ 0.005) and HIST1H2BO-YBX1 (YBX1: p ≤ 0.02) fusion transcripts, significantly associated with the patient's overall survival. Our systematic analysis resulted in novel fusion genes in LSTs suggesting a different etiology than CRCs. Fusion transcripts were observed more frequently in non-granular LSTs suggestive of genetically more unstable than granular LST. We hypothesize that NPM1-PTMA and HIST1H2BO-YBX1 could be implicated in LST development and progression and may also serve as a prognostic or diagnostic biomarker in future for better management of LSTs.

Cytokines and cecal microbiome modulations conferred by a dual vaccine in Salmonella-infected layers

Zoonotic Salmonella infection is a critical and challenging issue for public health. Since human infections are mainly associated with consuming contaminated chicken products, strategies to reduce Salmonella carriage and shedding are essential. Here we investigate the mechanisms of the live attenuated Salmonella vaccine (AviPro Salmonella Duo) against Salmonella Enteritidis (SE) infection. We focused on inflammatory-related cytokine expressions and cecal microbiota modulations in specific-pathogen-free (SPF) and field layers. Forty-eight 2-day-old SPF layers were randomly allotted into S.SEvc, S.SEc, S.Vc, and S.Ct groups in trial 1. The equal number of filed layers at 25 wk were allocated into SEvc, SEc, Vc, and Ct groups in trial 2. Each group contained 12 layers. Groups were further assigned for vaccination (S.Vc and Vc groups), SE challenge (S.SEc and SEc groups), vaccination and the following SE challenge (S.SEvc and SEvc groups), or the placebo treatment (S.Ct and Ct groups). Cecal tissues and contents of layers on day 14 post-SE-challenges were collected for cytokine mRNA expression and 16S rRNA metagenomic analyses. We found that SE challenges significantly upregulated expressions of IFNγ, IL-1β, IL-12β, and NFκB1A in SPF layers. The vaccine notably counteracted the levels of IFNα, IFNγ, and NFκB1A activated by SE attacks. The vaccination, SE challenge, and their combination did not significantly affect alpha diversities but promoted dissimilarities in microbial communities between groups. Eubacterium_coprostanoligenes and Faecalibacterium_prausnitzii were identified as contributory taxa in the cecal microbiota of SE-challenged and vaccinated SPF layers. A significantly higher abundance of Faecalibacterium_prausnitzii in the ceca further correlated with the vaccination conferred protection against SE infection. In contrast, Oscillibacter_valericigenes and Mediterraneibacter_glycyrrhizinilyticus were featured taxa in Salmonella-infected field layers. Megamonas_hypermegale and Megamonas_rupellensis were identified as featured taxa in vaccinated field layers compared to SE-infected layers. To conclude, applying a dual Salmonella vaccine in this study modulated expressions of inflammatory-related cytokines and the cecal microbiome in layers, contributing to protection against SE infection. The feature microbes are promising for developing predictive indices and as antibiotic alternatives added to feed to reduce the risk of Salmonella shedding and contamination.

Environmental sampling methods’ influence on detection of pathogens in cage-free aviary housing

The environmental sampling of layer housing systems is essential to identifying potential pathogens that are of concern to human health. To identify the natural occurrence of pathogens (Listeria, Campylobacter, and Salmonella) at various locations in a cage-free aviary housing system, swabs were collected when hens were 22 to 39 wks of age. Duplicate environmental swabs were taken and inoculated with a low dose (101 cfu) Salmonella Enteritidis (SE) and examined for the recovery of SE from environmental samples. Detection of Listeria (P < 0.0001) and Campylobacter (P < 0.0001) varied between the environmental sample types taken: concrete dust, drag swabs, egg belt dust, manure belt scraper swabs, and wall dust. Detection of Listeria (P < 0.0001) was the highest (70.0%) at the beginning of the study (22 wk) and decreased over time. Detection of Campylobacter (P < 0.001) was also the highest at 22 wk, however the decrease over time was more gradual. Interestingly, detection of Campylobacter (P < 0.0001) was the greatest in concrete dust samples (96.25%), which can be attributed to the presence of rodent excreta in the samples. Drag swabs and manure belt scraper swabs were the best sampling types for high detection of Listeria and Campylobacter. It should be noted that Listeria recovered was not of human health concern. No naturally occurring Salmonella was identified in this study. The recovery of the SE inoculum increased over time, reaching the greatest recovery in drag (81.25%; P < 0.0001), egg belt dust (100.00%; P < 0.0001) and wall dust swabs (100.00%; P < 0.0001) by 39 wk. This high rate of SE recovery occurred just before US mandatory SE environmental monitoring at 40 to 45 wks of age. Based on this study, the use of drag and manure belt scraper swabs are effective in detecting Listeria and Campylobacter in cage-free aviary housing. Along with good pest management, the occurrence of pathogens could be monitored and reduced in laying hen flocks.

In-vivo characterization of multidrug-resistant Salmonella enterica Serovar Enteritidis (SE) recovered from fertile eggs and baby chicks

The present study was conducted to isolate and characterize Salmonella spp. from hatching eggs and baby chicks. Additionally, the pathogenicity of the isolated Salmonella strains was assessed in one-day-old specific pathogen-free (SPF) chicks in-vivo. Samples from sick baby chicks from 14 broiler chicken farms (including 1 duck farm) and 150 egg batches from three breeder chicken farms were collected from 4 different governorates. Phenotypically identified Salmonella isolates were confirmed using species-specific multiplex-PCR targeting the inv -A gene for Salmonella genus, E -1 gene for Salmonella Enteritidis (SE) serovar, and Flic-C gene for Salmonella Typhimurium (ST) serovar. Confirmed SE isolates were further subjected to Random Amplified Polymorphic DNA (RAPD) fingerprinting. Phenotypic, multiplex-PCR, and RAPD fingerprinting confirmed six isolates (42.9%) from broiler chicken farms and two isolates from hatching egg batches (1.33%) as SE, of which eight were multidrug-resistant (MDR) strains with 0.214-0.786 MDR indices. In-vivo pathogenicity of selected multidrug-resistant (MDR) SE isolates was evaluated in one-day-old SPF chicks. Despite minor phenotypic diversity, most SE strains were highly invasive with variable mortality (50-100%). Interestingly, the lowest MDR indices were associated with high virulence in SE strains (mortality ≥85%) and vice versa. The study results showed the presence of SE in poultry in Egypt. The uncontrolled usage of antibiotics in poultry could be the reason for the increased prevalence of MDR Salmonella spp., which may limit Salmonella control measures and threaten public health.

Quantum Dot Nanobeads-Labelled Lateral Flow Immunoassay Strip for Rapid and Sensitive Detection of Salmonella Typhimurium Based on Strand Displacement Loop-Mediated Isothermal Amplification

• We developed a novel method for pathogen detection in foods. • It combined QBs-labelled LFIAS and SD-LAMP to achieve quantitative detection. • The combined test rapidly and sensitively detected Salmonella Thyphimurium. • Current approach does not require almost any equipment allowing point-of-care use. • The efficacy of the current test was confirmed in different food samples. Rapid, sensitive, point-of-care detection of pathogenic bacteria is important for food safety. In this study, we developed a novel quantum dot nanobeads-labelled lateral flow immunoassay strip (QBs-labelled LFIAS) combined with strand displacement loop-mediated isothermal amplification (SD-LAMP) for quantitative Salmonella Typhimurium (ST) detection. Quantum dot nanobeads (QBs) served as fluorescence reporters, providing good detection efficiency. The customizable strand displacement (SD) probe was used in LAMP to improve the specificity of the method and prevent by-product capture. Detection was based on a sandwich immunoassay. A fluorescence strip reader measured the fluorescence intensity (FI) of the test (T) line and control (C) line. The linear detection range of the strip was 10 2 –10 8 CFU·mL −1 . The visual limit of detection was 10 3 CFU·mL −1 , indicating that the system was 10-fold more sensitive than AuNPs-labelled test strips. ST specificity was analyzed in accordance with agarose gel outputs of PCR and SD-LAMP. We detected ST in foods with an acceptable recovery of 85%–110%. The method is rapid, simple, almost equipment-free, and suitable for bacterial detection in foods and for clinical diagnosis.

Virulence Range and New Pathological Pictures of Salmonella enteridits and Salmonella typhimurium Isolated from Ducklings in Experimental Infected Chicks

Salmonellosis is a major global pathogen in the poultry industry and is a significant public health concern. Ducks are known to be carriers of Salmonella. Therefore, monitoring salmonellosis is the most important strategy for preventing the disease. An experimental design was planned to study the pathogenicity of two Salmonella strains. One hundred and fifty chicks were divided into three groups; group one was inoculated with the Salmonella enteritidis strain, group two was inoculated with the Salmonella typhimurium strain, and group three was UN inoculated. Symptoms, postmortem lesions and mortality rate were recorded. The chick growth performance parameters were also determined. Using ANOVA for statistical analysis, there was a significant difference in body weight, body gain, feed consumption, and feed conversion ratio between the two infected groups and the blank group (uninoculated group). In this study, the prevalence of Salmonella enteritidis was (1.73%) and Salmonella typhimurium (0.43%) in imported ducklings in Egypt. Both Salmonella strains were subjected to an antimicrobial sensitivity test. It showed that Salmonella enteritidis had a 60% antimicrobial resistance profile and Salmonella typhimurium had a 20% antimicrobial resistance profile. Furthermore, genotypic characterization was performed and the seven virulence genes(stn, avrA, sopB, ompF, invA, Mgtc, Ssaq) were found. New pathological lesions of Salmonella infection were discovered, such as skull hemorrhage at 3 days and 6 days of age, and a liver similar to a button shape in necropsied infected chicks with Salmonella typhimurium at 21 days of age. Furthermore, hemorrhagic spots were observed on the duodenum. In the presence of Salmonella, Clostridium perferingens was discovered in a bacteriological investigation of duodenal lesions samples from infected chicks. At 30 days of age, administration of acetic acid (1%) as an alternative tool for controlling Salmonella. In conclusion, salmonellosis is a risk factor for necrotic enteritis, and using acetic acid to eliminate salmonella infection is insufficient.

MATHEMATICAL ANALYSIS OF TRANSMISSION DYNAMICS AND CONTROL OF SALMONELLA BACTERIAL INFECTION

The most prevalent health issue is salmonella infection. Every year, between 200 million and 1.3 billion people are infected with Salmonella. Salmonella spreads by direct animal contact, food and drink, and very infrequently, person-to-person contact via the fecal-oral route. It is estimated that 94% of salmonellosis transmission occurs through food. Salmonella infection is, in fact, a bacterial infection. It is crucial to utilize mathematical modeling to describe how biological and biomedical systems behave dynamically. The SIRS model of epidemics is the most often used mathematical model. Describing the patterns of Salmonella infectious disease in animal populations and the human population, we have formulated a SIRS epidemic model in our work. In significant part, the model was developed as a collection of ODEs based on the traits of transmission of infection. The occurrence of infection-free and endemic stable states was initially noted, and stability of the critical points of the model was later proven (infection-free and endemic). Following that, the fundamental reproduction number was calculated using the method of a next-generation matrix. Finally, the numerical simulations of this SIRS model have been completed. The analytical finding is explained using numerical simulations.

The small RNA STnc1480 contributes to the regulation of biofilm formation and pathogenicity in Salmonella typhimurium.

Salmonella Typhimurium (STM) is one of the most important food-borne bacteria that seriously harms livestock and human beings, which is capable of regulating the expression of its own genes in a variety of ways to adapt to a wide variety of adverse environmental stresses. To understand the regulatory roles of sRNA STnc1480 on the capability of STM, the STnc1480 gene-deficient strain △STnc1480 and its complement strain △STnc1480/STnc1480 were generated, and the impacts of STnc1480 gene deficiency on the capability of responding to different environmental stresses, biofilm(BF)formation and pathogenicity were analyzed, respectively. Then the target genes that were regulated by STnc1480 were also analyzed and explored. Compared with parent and complement strains, the deficiency of the STnc1480 gene significantly reduced the BF formation. Moreover, the capacities of adhesion and invasiveness of the △STnc1480 strain to macrophages were also significantly reduced, while the LD50 in mice was significantly increased. The bacterial loads in liver and spleen were significantly reduced, and the pathological damage was alleviated. It was confirmed that the STnc1480 could be complementary to the 5'-UTR (-52 to -71 bases) region of lpfA mRNA. The bacterial dual-plasmid reporting system confirmed that STnc1480 was capable of interacting with the mRNA of the lpfA gene, suggesting that STnc1480 can regulate the 5'-UTR of the lpfA mRNA at post-transcription level to reduce the expression of the bacterial fimbria, thus reducing the BF formation and pathogenicity of STM.

Disseminated Salmonella Infection Coexisting with Thymoma

A 21-year-old boy presented with high grade fever, diffuse chest pain and exertional breathlessness of one month duration. Radiologically he had a large lobulated anterior mediastinal mass with necrotic thick enhancing septaes. Histopathology of the mass was suggestive of thymoma and culture from the necrotic aspirate yielded Salmonella typhi. The same pathogen was isolated in subsequent blood and sputum cultures. This current report describes the rare association of salmonella infection with thymoma.

Genomic, probiotic, and metabolic potentials of Liquorilactobacillus nagelii AGA58, a novel bacteriocinogenic motile strain isolated from lactic acid-fermented shalgam

This study aimed to perform genomic, probiotic, and metabolic characterization of a novel Liquorilactobacillus nagelii AGA58 isolated from a lactic acid-fermented shalgam beverage to understand its metabolic potentials and probiotic features. AGA58 is gram-positive, motile, catalase-negative and appears as short rods under the light-microscope. The AGA58 chromosome comprises a single linear chromosome of 2,294,635 bp that is predicted to carry 2135 coding sequences, including 45 tRNA genes, 3 mRNA, and 3 rRNA operons. The genome has a G+C content of 36.9%, including 55 pseudogenes and a single intact prophage. AGA58 is micro-anaerobic due to achieving a shorter doubling time and faster growth rate than micro-aerophilic conditions. It carries flagellar biosynthesis protein-encoding genes predicting motile behavior, which was confirmed with the in vitro motility test. AGA58 is an obligatory homofermentative lactobacillus that can ferment hexose sugars such as galactose, glucose, fructose, sucrose, mannose, N-acetyl glucosamine, maltose, and trehalose to lactate through glycolysis. No acid production from pentoses implies that five-carbon sugars are being utilized for purine and pyrimidine synthesis. Putative pyruvate metabolism revealed formate, malate, oxaloacetate, acetate, acetaldehyde, acetoin, and lactate forms from pyruvate. AGA58 is predicted to encode the LuxS gene and biosynthesis of class IIa and Blp family class-II bacteriocins suggesting this bacterium's antimicrobial potential, linked to antagonism tests that AGA58 can inhibit Escherichia coli ATCC 43895, Salmonellaenterica serovar Typhimurium ATCC 14028, and Klebsiellapneumonia ATCC 13883. Moreover, AGA58 is tolerant to acid and bile concentrations simulating the human gastrointestinal conditions depicting the probiotic potential of the organism as the first report in literature within the same species.

High voltage atmospheric cold plasma decontamination of Salmonella enteritidis on chicken eggs

Salmonella enteritidis (SE) accounts for more than 70% of Salmonella spp. infections in humans with a primary source being chicken eggs, that can result from post-lay SE cross-contamination of the shell from contaminated equipment or the environment. The objective of this study was to apply a HVACP treatment that can achieve a minimum 5-log reduction in SE on the surface of artificially inoculated shell eggs with an initial bacterial load of 108 CFU/egg, after a previous disinfection. Optimized HVACP treatment conditions were an indirect treatment with air at 60% humidity at 100 kV for one minute treatment and six hours post-treatment or alternatively, five minutes of treatment and four hours post-treatment. Egg quality parameters of Haugh unit (HU), pH, color, and vitelline membrane and shell strength were tested under the optimized conditions and showed no significant difference (p > 0.05) between treated and untreated eggs.Industrial relevance: Missing information for a possible scale up of a cold plasma system for egg surface decontamination has been addressed by an optimization of HVACP treatment focused on treatment and post-treatment time, essential parameters to have into account in the food industry. These results demonstrate that HVACP is an effective decontamination method for SE on chicken shell eggs and provides a baseline for a future scale up of the process, showing that different combinations of treatment variables can achieve the desired decontamination without affecting to key quality parameters of the egg such as Haugh Unit or vitelline membrane strength.

Effects of fumonisin and Salmonella infection in the expression of Toll-like receptors in chicken ovary

Mycotoxins are secondary metabolites produced mainly by fungi that contaminate animal feed and basic food products throughout the world. Currently, more than 500 mycotoxins are reported and one of the most important concern to public health and agriculture is Fumonisin B1 (FB1). FB1, a mycotoxin produced by Fusarium moniliforme, is a contaminant of animal feed with various and complex cellular effects. Although FB1 has been associated with various diseases in animals, to date few studies have been performed to evaluate the endocrine disrupting effects of FB1 and more particularly the effects in the innate immune mechanisms of farm animals and more specifically in poultry species. As the family of Toll-like receptors (TLRs) is one of the key molecules of the innate immune system, the aim of the present study was to evaluate the transcriptional changes of TLRs in the chicken ovary in vivo, in chicks fed with FB1 and in response to Salmonella Enteritidis (SE) infection. RNA was extracted from the ovaries of sexually mature and aged birds, treated with FB1 and SE. Quantitative real-time PCR analysis revealed that FB1 and SE infection resulted in a significant down regulation of 5 TLR genes in the ovary of sexual mature and aged birds. These findings suggest that the mycotoxin FB1 suppresses the innate immune system of the chicken reproductive organs, through alteration in the expression of certain TLR genes.

Exogenous D-ribose promotes gentamicin treatment of several drug-resistant Salmonella.

The metabolic microenvironment of bacteria impacts drug efficacy. However, the metabolic mechanisms of drug-resistant Salmonella spp. remain largely unknown. This study characterized the metabolic mechanism of gentamicin-resistant Salmonella Choleraesuis and found that D-ribose increased the gentamicin-mediated killing of this bacteria. Non-targeted metabolomics of homologous gentamicin-susceptible Salmonella Choleraesuis (SCH-S) and gentamicin-resistant S. Choleraesuis (SCH-R) was performed using UHPLC-Q-TOF MS. The metabolic signature of SCH-R included disrupted central carbon metabolism and energy metabolism, along with dysregulated amino acid and nucleotide metabolism, vitamin and cofactor metabolism, and fatty acid synthesis. D-ribose, the most suppressed metabolite in SCH-R, was shown to strengthen gentamicin efficacy against SCH-R and a clinically isolated multidrug-resistant strain. This metabolite had a similar impact on Salmonella. Derby and Salmonella. Typhimurium. D-ribose activates central carbon metabolism including glycolysis, the pentose phosphate pathway (PPP), and the tricarboxylic acid cycle (TCA cycle), increases the abundance of NADH, polarizes the electron transport chain (ETC), and elevates the proton motive force (PMF) of cells, and induces drug uptake and cell death. These findings suggest that central carbon metabolism plays a critical role in the acquisition of gentamicin resistance by Salmonella, and that D-ribose may serve as an antibiotic adjuvant for gentamicin treatment of resistant bacterial infections.

Implications for risk management of foodborne pathogens in China from the outbreak of monophasic salmonella enterica serovar Typhimurium contaminated chocolate products

Outbreaks caused by highly industrialized food companies are characterized by cross-border, trans-regional, rapid and unpredictable, related to serious disease and economic burden. A cluster of cases with monophasic salmonella enterica serovar Typhimurium ST34 infection suspected to be associated with consumption of contaminated chocolate products have been reported in several Europe countries since December 2021. After retrospective investigations, the buttermilk circuit in the Belgian factory was suspected to be the point of origin of the contamination. This outbreak could provide a reference for the risk management of foodborne pathogens contamination in China. The objective of this paper was to summarize the process and characteristics of the outbreak of monophasic S. Typhimurium caused by contaminated chocolate products, analyze the characteristics of ST34 monophasic S. Typhimurium and the microbial management measures in the process of chocolate products, and systematically discuss the suggestions for the risk management of foodborne pathogens contamination and countermeasures for the rapid development of industrialization of food enterprises in China, in order to provide scientific and technological support for the prevention and control, prediction and early warning of sudden cases in China.

High-throughput sequencing-based metagenomic and transcriptomic analysis of intestine in piglets infected with salmonella

Salmonella enterica serovar Typhimurium isolate HJL777 is a virulent bacterial strain in pigs. The high rate of salmonella infection are at high risk of non-typhoidal salmonella gastroenteritis development. Salmonellosis is most common in young pigs. We investigated changes in gut microbiota and biological function in piglets infected with salmonella via analysis of rectal fecal metagenome and intestinal transcriptome using 16S rRNA and RNA sequencing. We identified a decrease in Bacteroides and increase in harmful bacteria such as Spirochaetes and Proteobacteria by microbial community analysis. We predicted that reduction of Bacteroides by salmonella infection causes proliferation of salmonella and harmful bacteria that can cause an intestinal inflammatory response. Functional profiling of microbial communities in piglets with salmonella infection showed increasing lipid metabolism associated with proliferation of harmful bacteria and inflammatory responses. Transcriptome analysis identified 31 differentially expressed genes. Using gene ontology and Innate Immune Database analysis, we identified that BGN, DCN, ZFPM2 and BPI genes were involved in extracellular and immune mechanisms, specifically salmonella adhesion to host cells and inflammatory responses during infection. We confirmed alterations in gut microbiota and biological function during salmonella infection in piglets. Our findings will help prevent disease and improve productivity in the swine industry.

FABP4 in Paneth cells regulates antimicrobial protein expression to reprogram gut microbiota

ABSTRACT Antimicrobial proteins possess a broad spectrum of bactericidal activity and play an important role in shaping the composition of gut microbiota, which is related to multiple diseases such as metabolic syndrome. However, it is incompletely known for the regulation of defensin expression in the gut Paneth cells. Here, we found that FABP4 in the Paneth cells of gut epithelial cells and organoids can downregulate the expression of defensins. FABP4fl/flpvillinCreT mice were highly resistance to Salmonella Typhimurium (S.T) infection and had increased bactericidal ability to pathogens. The FABP4-mediated downregulation of defensins is through degrading PPARγ after K48 ubiquitination. We also demonstrate that high-fat diet (HFD)-mediated downregulation of defensins is through inducing a robust FABP4 in Paneth cells. Firmicutes/Bacteroidetes (F/B) ratio in FABP4fl/flpvillinCreT mice is lower than control mice, which is opposite to that in mice fed HFD, indicating that FABP4 in the Paneth cells could reprogram gut microbiota. Interestingly, FABP4-mediated downregulation of defensins in Paneth cells not only happens in mice but also in human. A better understanding of the regulation of defensins, especially HFD-mediated downregulation of defensin in Paneth cells will provide insights into factor(s) underlying modern diseases. Abbreviations: FABP4: Fatty acid binding protein 4; S. T: SalmonellaTyphimurium; HFD: High-fat diet; Defa: α-defensin; 930HD5: Human α-defensin 5; HD6: Human α-defensin 6;F/B: Firmicutes/Bacteroidetes; SFB: Segmental filamentousbacteria; AMPs: Antimicrobial peptides; PPARγ:Peroxisome proliferator-activated receptor γ; P-PPAR:Phosphorylated PPAR; Dhx15: DEAD-box helicase 15; 935EGF: Epidermal growth factor; ENR: Noggin andR-spondin 1; CFU: Colony forming unit; Lyz1: Lysozyme1; Saa1: Serum amyoid A 1; Pla2g2a: Phospholipase A2,group IIA; MMP-7: Matrix metalloproteinase; AU-PAGE:Acid-urea polyacrylamide gel electrophoresis; PA: Palmitic 940acid; GPR40: G-protein-coupled receptor; GF: Germ-free;EGF: Epidermal growth factor; LP: Lamina propria; KO:Knock out; WT: Wild-type.

Cloning, Expression, Re-folding, and Purification of Protein Flic (salmonella Enteritidis) with Deletion of Amino Acids 220-320

In order to develop high-performance subunit vaccines, many studies are currently aiming at the development of immunoadjuvants. Flagellin protein (FliC) contained in the Salmonella’s filament is one of the potential candidates for this purpose. However, the high antigenic property of FliC has made it difficult to apply for many vaccines. A variant with the deletion of amino acids from 220 to 320 of flagellin has been proven to have an adjuvant effect with lower immunogenicity. In this present study, we cloned and expressed FliCD220-320 recombinant in Escherichia coli system. The expression of FliCΔ220-320 was induced by IPTG and confirmed by SDS-PAGE and Western Blot probed with 6xHis tag antibody. Results showed that most of the expressed protein is insoluble. The targeted protein was then solubilized, re-folded and purified by affinity chromatography method with the purity of 80 %. With these results, we successfully expressed FliCD220-320 recombinant protein and this is a source for the evaluation and development of immune adjuvants.

Intracellular autolytic whole cell Salmonella vaccine prevents colonization of pathogenic Salmonella Typhimurium in chicken

Salmonella enterica (SE) is a major foodborne bacterial pathogen in the United States, commonly found as the normal flora of various animals that is attributed to causing at least 1.2 million infections annually. Poultry plays a major role in disseminating SE through direct contact with live animals and consumption of contaminated products. Vaccinating poultry against SE is a sustainable approach that can reduce SE in the host, preventing future infections in humans. An intracellular autolytic SE serovar Typhimurium vaccine (STLT2+P13+19) was developed by integrating genes 13 (holin) and 19 (lysozyme) of bacteriophage P22 into the bacterial chromosome. These were inserted downstream of sseA, an SPI-2 chaperone in SE that expresses during the intracellular phase of SE. Intracellular viability of STLT2+P13+19 reduced by 94.42% at 24 hr compared to the wild type in chicken macrophage cells (HD-11), whereas growth rate and adhesion ability remained unchanged. Inoculating STLT2+P13+19 in HD-11 significantly enhanced the relative log fold expression of genes associated to production of pro-inflammatory cytokines (IL-1β, IL-6, IL-8, IL-10, IL-12 p40, IL-18, and GM-CSF) and Toll-like-receptors (TRL-3 and 7). Vaccination of an in vivo chicken model demonstrated significant changes in secretion of iNOS, IL-6, IL-8, IL-12, and TNF-α, as well as a reduction in the intestinal colonization of SE serovar Typhimurium. Microbiome analysis of cecal fluid using 16S rRNA gene sequencing also showed modulation of intestinal microbial composition, specifically a decrease in relative abundance of Proteobacteria and increasing Firmicutes. This study provides insight into a novel vaccine design that could make food products safer without the use of synthetic compounds.

Detection of enterobacteria using polymerase chain reaction real-time

The purpose of the work is to carry out a real-time polymerase chain reaction for the isolation of enterobacteria from the faeces of the maize snake and their identification.Fecal masses after molting were collected from a male maize snake named Rabbit of Bloodred het Pied-Sided morph.Egg release date: 06/19/2020.Isolation of nucleic acids from faecal samples was carried out by the sorption method using the AmpliPrime DNA-sorb-AM reagent kit (Central Research Institute of Epidemiology) in accordance with the manufacturer's instructions.For amplification, a test was used the Salm-IDS system for the detection of pathogenic Salmonella (Samonella spp et Salmonella Typhi). The amplification process was carried out in a LightCicler 96 (Roche) PCR-RT instrument.In the study of feces from a reptile by the molecular method, the genus Salmonella was discovered.The PCR study did not allow for species identification and determination of the viability of the microorganism, it is necessary to create a scheme for laboratory control of salmonella infection, which will include both the PCR method and bacteriological studies.

Screening of Essential Oils and Effect of a Chitosan-Based Edible Coating Containing Cinnamon Oil on the Quality and Microbial Safety of Fresh-Cut Potatoes

Fresh-cut potatoes (Solanum tuberosum L.) are a popular food owing to their freshness, convenience, and health benefits. However, they might present a potentially high health risk to consumers during transportation, processing, and marketing. In the current study, 18 essential oils (EOs) were screened to test their antimicrobial activity against Listeria monocytogenes (LM), Salmonella typhimurium (ST), Staphylococcus aureus (SA), and Escherichia coli O157:H7 (EC O157:H7). The antibacterial effectiveness of a chitosan edible coating (EC) containing cinnamon oil was evaluated against microorganisms on fresh-cut potatoes. Fresh-cut potatoes were treated with chitosan EC and chitosan EC containing different concentrations (0, 0.2, 0.4, and 0.6%, v/v) of cinnamon oil, and uncoated samples served as the control. The viability of naturally occurring microorganisms and artificially inoculated LM on fresh-cut potatoes was evaluated, as were the colour, weight loss, and firmness of potatoes, every 4 days for a total of 16 days at 4 °C. The results demonstrate that the inhibition zones of cinnamon, oregano, and pomelo oils were 16.33–30.47 mm, 22.01–31.31 mm, and 21.75–35.18 mm, respectively. The cinnamon oil exhibits the lowest MIC (0.313 μL/mL) for four foodborne pathogens compared with oregano and pomelo oils. The chitosan EC containing 0.2% cinnamon oil effectively maintains the quality of fresh-cut potatoes including inhibiting the browning, preventing the weight loss, and maintaining the firmness. The decline of total plate counts, yeast and mould counts, total coliform counts, lactic acid bacteria count, and Listeria monocytogenes in EC containing 0.2% cinnamon oil were 2.14, 1.92, 0.98, 0.73, and 1.94 log cfu/g, respectively. Therefore, the use of chitosan EC containing cinnamon oil might be a promising approach for the preservation of fresh-cut potatoes.