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1.
J Biol Chem ; : 107758, 2024 Sep 09.
Artículo en Inglés | MEDLINE | ID: mdl-39260696

RESUMEN

S. Typhi, the cause of typhoid fever, is a bacterial pathogen of substantial global importance. Typhoid toxin is a secreted AB-type toxin that is a key S. Typhi virulence factor encoded within a 5-gene genetic islet. Four genes in this islet have well-defined roles in typhoid toxin biology, however the function of the fifth gene is unknown. Here, we investigate the function of this gene, which we name ttaP. We show that ttaP is co-transcribed with the typhoid toxin subunit cdtB, and we perform genomic analyses that indicate that TtaP is very highly conserved in typhoid toxin islets found in diverse salmonellae. We show that TtaP is a distant homolog of group XIV secreted phospholipase A2 (PLA2) enzymes, and experimentally demonstrate that TtaP is a bona fide PLA2. Sequence and structural analyses indicate that TtaP differs substantially from characterized PLA2s, and thus represents a novel class of PLA2. Secretion assays revealed that TtaP is neither co-secreted with typhoid toxin, nor is it required for toxin secretion. Although TtaP is a phospholipase that remains associated with the S. Typhi cell, assays that probed for altered cell envelope integrity failed to identify any differences between wild-type S. Typhi and a ttaP deletion strain. Collectively, this study identifies a biochemical activity for the lone uncharacterized typhoid toxin islet gene and lays the groundwork for exploring how this gene factors into S. Typhi pathogenesis. This study further identifies a novel class of PLA2, enzymes that have a wide range of industrial applications.

2.
Bull Exp Biol Med ; 177(2): 281-286, 2024 Jun.
Artículo en Inglés | MEDLINE | ID: mdl-39096449

RESUMEN

Different methods for fixing biofilms of Staphylococcus aureus and Salmonella enterica for light and electron microscopy were compared. Paraformaldehyde fixation did not preserve biofilm integrity during dehydration; Ito-Karnovsky fixation revealed cell morphology, but did not preserve the matrix. Ruthenium red combined with aldehydes allowed the matrix to be preserved and visualized. An analysis of the ultrastructure of S. aureus and S. enterica cells in biofilms and suspensions at various fixations is presented. The ultrastructure of the biofilm matrix has been described.


Asunto(s)
Biopelículas , Salmonella enterica , Staphylococcus aureus , Biopelículas/crecimiento & desarrollo , Staphylococcus aureus/fisiología , Salmonella enterica/fisiología , Salmonella enterica/ultraestructura , Salmonella enterica/crecimiento & desarrollo , Formaldehído , Fijadores/farmacología , Fijadores/química , Microscopía Electrónica , Polímeros
3.
Front Bioinform ; 4: 1415078, 2024.
Artículo en Inglés | MEDLINE | ID: mdl-39184336

RESUMEN

Monitoring data submitted to the National Center for Biotechnology Information's Pathogen Detection whole-genome sequence database, which includes the foodborne bacterial pathogens Listeria monocytogenes, Salmonella enterica, and Escherichia coli, has proven effective for detecting emerging outbreaks. As part of the submission process, new sequence data are typed using a whole-genome multi-locus sequence typing scheme and clustered with sequences already in the database. Publicly available text files contain the results of these analyses. However, contextualizing and interpreting this information is complex. We present the Rapid Intuitive Pathogen Surveillance (RIPS) tool, which shows the results of the NCBI Rapid Reports, along with appropriate metadata, in a graphical, interactive dashboard. RIPS makes the information in the Rapid Reports useful for real-time surveillance of genome sequence databases.

4.
China CDC Wkly ; 6(33): 825-833, 2024 Aug 16.
Artículo en Inglés | MEDLINE | ID: mdl-39211441

RESUMEN

Introduction: Highly fluoroquinolone-resistant Salmonella enterica serovar Kentucky (S. Kentucky) of sequence type (ST) 198 has emerged as a global multidrug-resistant (MDR) clone, posing a threat to public health. Methods: Whole genome sequencing and antibiotic susceptibility testing was used to characterize the population structure and evolutionary history of 54 S. Kentucky isolates recovered from food and human clinical cases in Beijing from 2016 to 2023. Results: All 54 S. Kentucky ST198 isolates exhibited resistance to quinolones, carrying point mutations in the quinolone resistance-determining regions (gyrA_S83F and parC_S80I). Resistance to other antibiotics (folate pathway inhibitors, cephems, aminoglycosides, phenicols, rifamycin, fosfomycin, macrolides, and tetracyclines), mediated by the sul1, sul2, dfrA14, bla CTX-M, bla TEM-1B, aac(3)-Id, aadA2, aadA7, aph(3')-I, aph(3'')-Ib, rmtB, floR, arr-2, fosA, mph(A), and tet(A) genes, was also observed in different combinations. The Beijing S. Kentucky ST198 evolutionary tree was divided into clades 198.2-1 and 198.2-2, which were further differentiated into three subclades: 198.2-2A, 198.2-2B, and 198.2-2C. Compared with the extended-spectrum ß-lactamase-encoding gene bla CTX-M-14b in 198.2-1, the co-existence of bla CTX-M-55 and bla TEM-1B, as well as chromosomally located qnrS1, was detected in most 198.2-2 isolates, which showed more complex MDR phenotypes. S. Kentucky ST198 outbreak isolates derived from two predominant clonal sources: 198.2-1 with cgST236434 and 198.2-2A with cgST296405. Conclusions: The S. Kentucky population in Beijing is genetically diverse, consisting of multiple co-circulating lineages that have persisted since 2016. Strengthening surveillance of food and humans will aid in implementing measures to prevent and control the spread of AMR.

5.
Artículo en Inglés | MEDLINE | ID: mdl-39212846

RESUMEN

Foodborne diseases triggered by various infectious micro-organisms are contributing significantly to the global disease burden as well as to increasing mortality rates. Salmonella enterica belongs to the most prevalent form of bacteria accountable for significant burden of foodborne illness across the globe. The conventional therapeutic approach to cater to Salmonella enterica-based infections relies on antibiotic therapy, but the rapid emergence of the antibiotic resistance strains of Salmonella sp. necessitates the development of alternative treatment and prevention strategies. In light of this growing concern, the scientific community is rigorously exploring novel phytochemicals harnessed from medicinally important plants as a promising approach to curb Salmonella enterica infections. A variety of phytochemicals belonging to alkaloids, phenols, flavonoid, and terpene classes are reported to exhibit their inhibitory activity against bacterial cell communication, membrane proteins, efflux pumps, and biofilm formation among drug resistant Salmonella strains. The present review article delves to discuss the emergence of antibiotic resistance among Salmonella enterica strains, various plant sources, identification of phytochemicals, and the current state of research on the use of phytochemicals as antimicrobial agents against Salmonella enterica, shedding light on the promising potential of phytochemicals in the fight against this pathogen.

6.
Cureus ; 16(7): e65090, 2024 Jul.
Artículo en Inglés | MEDLINE | ID: mdl-39171062

RESUMEN

Salmonella-induced peritonitis, secondary to spontaneous gastrointestinal perforation, is a rare but potentially life-threatening condition. We present a case of a 62-year-old female with a history of systemic hypertension, who presented with diffuse abdominal pain and altered bowel habits. Initial evaluation suggested acute gastroenteritis, but worsening symptoms led to emergent exploratory laparotomy, revealing a gastric/duodenal perforation. Peritoneal fluid analysis and culture confirmed Salmonella Paratyphi A infection. The patient underwent an emergency laparotomy with omental patch repair and received intravenous ceftriaxone, leading to a full recovery. This case underscores the importance of considering Salmonella infection in the differential diagnosis of peritonitis, prompt surgical intervention, and appropriate antimicrobial therapy for optimal management and outcomes. Further research on epidemiological trends, host-pathogen interactions, and antibiotic resistance should be explored. Clinical studies should refine diagnostic criteria and treatment protocols, while animal models can aid in understanding pathophysiology and vaccine development for Salmonella peritonitis. Public health interventions and environmental studies will enhance prevention and control strategies.

7.
Front Microbiol ; 15: 1387830, 2024.
Artículo en Inglés | MEDLINE | ID: mdl-39211316

RESUMEN

Salmonella enterica is a foodborne pathogen associated with both typhoid and non-typhoid illness in humans and animals. This problem is further exacerbated by the emergence of antibiotic-resistant strains of Salmonella enterica. Therefore, to meet public health and safety, there is a need for an alternative strategy to tackle antibiotic-resistant bacteria. Bacteriophages or (bacterial viruses), due to their specificity, self-dosing, and antibiofilm activity, serve as a better approach to fighting against drug-resistant bacteria. In the current study, a broad-host range lytic phage phiSalP219 was isolated against multidrug-resistant Salmonella enterica serotypes Paratyphi from a pond water sample. Salmonella phage phiSalP219 was able to lyse 28/30 tested strains of Salmonella enterica. Salmonella phage phiSalP219 exhibits activity in acidic environments (pH3) and high temperatures (70°C). Electron microscopy and genome analysis revealed that phage phiSalP219 is a member of class Caudoviricetes. The genome of Salmonella phage phiSalP219 is 146Kb in size with 44.5% GC content. A total of 250 Coding Sequence (CDS) and 25 tRNAs were predicted in its genome. Predicted open reading frames (ORFs) were divided into five groups based on their annotation results: (1) nucleotide metabolism, (2) DNA replication and transcription, (3) structural proteins, (4) lysis protein, and (5) other proteins. The absence of lysogeny-related genes in their genome indicates that Salmonella phage phiSalP219 is lytic in nature. Phage phiSalP219 was also found to be microbiologically safe (due to the absence of toxin or virulence-related genes) in the control of Salmonella enterica serovar Typhimurium infections in the ready-to-eat meat and also able to eradicate biofilm formed by the same bacterium on the borosilicate glass surface.

8.
Microbiol Resour Announc ; 13(9): e0000624, 2024 Sep 10.
Artículo en Inglés | MEDLINE | ID: mdl-39162457

RESUMEN

In this study, we performed whole-genome sequencing of three ciprofloxacin-resistant Salmonella Reading strains isolated from poultry meat. Genomes of S. Reading strains contained an average of 4.81 Mbp size with 52.1% GC. The isolates exhibited blaOXA-10, aac [6']-Iaa, aadA1, cmlA1, qnrS1, and tetA resistance genes and IncX1 and IncX2 plasmids.

9.
Microbiol Resour Announc ; 13(9): e0058624, 2024 Sep 10.
Artículo en Inglés | MEDLINE | ID: mdl-39162465

RESUMEN

Oxford Nanopore long reads of simulated bacterial communities from fresh spinach and surface water were generated (R9.4.1+SQK-LSK109 and R10.4+SQK-LSK112; 0.5, one, and two million reads). Salmonella enterica serotype Heidelberg, Montevideo, or Typhimurium was included alone or in combination in the spinach community, while the water community harbored Pseudomonas aeruginosa.

10.
mBio ; 15(9): e0164224, 2024 Sep 11.
Artículo en Inglés | MEDLINE | ID: mdl-39152718

RESUMEN

Bacteria acquire P primarily as inorganic orthophosphate (Pi, PO43-). Once internalized, Pi is rapidly assimilated into biomass during the synthesis of ATP. Because Pi is essential, but excessive ATP is toxic, the acquisition of environmental Pi is tightly regulated. In the bacterium Salmonella enterica (Salmonella), growth in Pi-limiting environments activates the membrane sensor histidine kinase PhoR, leading to the phosphorylation of its cognate transcriptional regulator PhoB and subsequent transcription of genes involved in adaptations to low Pi. Pi limitation promotes PhoR kinase activity by altering the conformation of a membrane signaling complex comprised of PhoR, the multicomponent Pi transporter system PstSACB and the regulatory protein PhoU. However, the identity of the Pi-starvation signal and how it controls PhoR activity remain unknown. Here, we identify conditions where the PhoB and PhoR signal transduction proteins can be maintained in an inactive state when Salmonella is grown in media lacking Pi. Our results demonstrate that PhoB/PhoR is activated by an intracellular P-insufficiency signal.IMPORTANCEIn enteric bacteria, the transcriptional response to phosphorus (P) starvation is controlled by a specialized signal transduction system comprised of a membrane-bound, multicomponent signal sensor, and a cytoplasmic transcriptional factor. Whereas this system has been primarily studied in the context of phosphate (Pi) starvation, it is currently unknown how this stress initiates signal transduction. In the current study, we establish that this signaling system is regulated by a cytoplasmic signal arising from insufficient P. We demonstrate that rather than responding to extracellular conditions, cells couple the activation of their P starvation response to the availability of cytoplasmic P. This regulatory logic may enable cells to prevent toxicity resulting from excessive Pi acquisition and hinder the onset of a P starvation response when their metabolic demands are being met through the consumption of P sources other than Pi.


Asunto(s)
Proteínas Bacterianas , Regulación Bacteriana de la Expresión Génica , Fósforo , Salmonella enterica , Transducción de Señal , Proteínas Bacterianas/metabolismo , Proteínas Bacterianas/genética , Fósforo/metabolismo , Salmonella enterica/genética , Salmonella enterica/metabolismo , Fosforilación , Fosfatos/metabolismo
11.
Microbiol Resour Announc ; 13(9): e0000924, 2024 Sep 10.
Artículo en Inglés | MEDLINE | ID: mdl-39162441

RESUMEN

We present a complete genome of Salmonella enterica subsp. enterica serovar Hessarek isolated from a human stool from an outbreak linked to egg consumption in South Australia. Orientation of the rrn operon and characteristics of the Salmonella virulence plasmid indicates that this serovar is virulent toward humans and birds.

12.
Microbiol Resour Announc ; 13(9): e0028924, 2024 Sep 10.
Artículo en Inglés | MEDLINE | ID: mdl-39162450

RESUMEN

Antimicrobial exposure can potentially lead to increased antimicrobial resistance plasmid transfer. Sequencing data were collected from the RNA of pairs of Salmonella enterica and Escherichia coli exposed or not exposed to tetracycline over time to determine differences in transcription-associated tetracycline exposure during in vitro conjugation experiments.

13.
Appl Environ Microbiol ; 90(8): e0091524, 2024 Aug 21.
Artículo en Inglés | MEDLINE | ID: mdl-38984844

RESUMEN

Humans and animals encounter a summation of exposures during their lifetime (the exposome). In recent years, the scope of the exposome has begun to include microplastics. Microplastics (MPs) have increasingly been found in locations, including in animal gastrointestinal tracts, where there could be an interaction with Salmonella enterica serovar Typhimurium, one of the commonly isolated serovars from processed chicken. However, there is limited knowledge on how gut microbiomes are affected by microplastics and if an effect would be exacerbated by the presence of a pathogen. In this study, we aimed to determine if acute exposure to microplastics in vitro altered the gut microbiome membership and activity. The microbiota response to a 24 h co-exposure to Salmonella enterica serovar Typhimurium and/or low-density polyethylene (PE) microplastics in an in vitro broiler cecal model was determined using 16S rRNA amplicon sequencing (Illumina) and untargeted metabolomics. Community sequencing results indicated that PE fiber with and without S. Typhimurium yielded a lower Firmicutes/Bacteroides ratio compared with other treatment groups, which is associated with poor gut health, and overall had greater changes to the cecal microbial community composition. However, changes in the total metabolome were primarily driven by the presence of S. Typhimurium. Additionally, the co-exposure to PE fiber and S. Typhimurium caused greater cecal microbial community and metabolome changes than either exposure alone. Our results indicate that polymer shape is an important factor in effects resulting from exposure. It also demonstrates that microplastic-pathogen interactions cause metabolic alterations to the chicken cecal microbiome in an in vitro chicken cecal mesocosm. IMPORTANCE: Researching the exposome, a summation of exposure to one's lifespan, will aid in determining the environmental factors that contribute to disease states. There is an emerging concern that microplastic-pathogen interactions in the gastrointestinal tract of broiler chickens may lead to an increase in Salmonella infection across flocks and eventually increased incidence of human salmonellosis cases. In this research article, we elucidated the effects of acute co-exposure to polyethylene microplastics and Salmonella enterica serovar Typhimurium on the ceca microbial community in vitro. Salmonella presence caused strong shifts in the cecal metabolome but not the microbiome. The inverse was true for polyethylene fiber. Polyethylene powder had almost no effect. The co-exposure had worse effects than either alone. This demonstrates that exposure effects to the gut microbial community are contaminant-specific. When combined, the interactions between exposures exacerbate changes to the gut environment, necessitating future experiments studying low-dose chronic exposure effects with in vivo model systems.


Asunto(s)
Ciego , Pollos , Microbioma Gastrointestinal , Metaboloma , Polietileno , Salmonella typhimurium , Animales , Pollos/microbiología , Ciego/microbiología , Microbioma Gastrointestinal/efectos de los fármacos , Salmonella typhimurium/efectos de los fármacos , Polietileno/metabolismo , Metaboloma/efectos de los fármacos , Microplásticos , ARN Ribosómico 16S/genética , Salmonelosis Animal/microbiología
14.
Prev Vet Med ; 230: 106261, 2024 Sep.
Artículo en Inglés | MEDLINE | ID: mdl-38964208

RESUMEN

Salmonellosis is one of the most common foodborne diseases worldwide, with the ability to infect humans and animals. Antimicrobial resistance (AMR) and, particularly, multidrug resistance (MDR) among Salmonella enterica poses a risk to human health. Antimicrobial use (AMU) regulations in livestock have been implemented to reduce AMR and MDR in foodborne pathogens. In this study, we used an integrated machine learning approach to investigate Salmonella AMR and MDR patterns before and after the implementation of AMU restrictions in agriculture in the United States. For this purpose, Salmonella isolates from cattle in the National Antimicrobial Resistance Monitoring System (NARMS) dataset were analysed using three descriptive models consisting of hierarchical clustering, network analysis, and association rule mining. The analysis showed the impact of the United States' 2012 extra-label cephalosporin regulations on AMR trends and revealed a distinctive MDR pattern in the Dublin serotype. The results also indicated that each descriptive model provides insights on a specific aspect of resistance patterns and, therefore, combining these approaches make it possible to gain a deeper understanding of AMR.


Asunto(s)
Antibacterianos , Farmacorresistencia Bacteriana Múltiple , Aprendizaje Automático , Salmonelosis Animal , Salmonella enterica , Salmonella enterica/efectos de los fármacos , Animales , Bovinos , Salmonelosis Animal/microbiología , Antibacterianos/farmacología , Estados Unidos , Enfermedades de los Bovinos/microbiología , Enfermedades de los Bovinos/tratamiento farmacológico
15.
Can J Microbiol ; 70(9): 358-369, 2024 Sep 01.
Artículo en Inglés | MEDLINE | ID: mdl-38990097

RESUMEN

Salmonella enterica serovars are zoonotic bacterial that cause foodborne enteritis. Due to bacteria's antibiotic resistance, using bacteriophages for biocontrol and treatment is a new therapeutic approach. In this study, we isolated, characterized, and analyzed the genome of vB_SenS_TUMS_E19 (E19), a broad host range Salmonella bacteriophage, and evaluated the influence of E19 on liquid eggs infected with Salmonella enterica serovar Enteritidis. Transmission electron microscopy showed that the isolated bacteriophage had a siphovirus morphotype. E19 showed rapid adsorption (92% in 5 min), a short latent period (18 min), a large burst size (156 PFU per cell), and a broad host range against different Salmonella enterica serovars. Whole-genome sequencing analysis indicated that the isolated phage had a 42 813 bp long genome with 49.8% G + C content. Neither tRNA genes nor those associated with antibiotic resistance, virulence factors, or lysogenic formation were detected in the genome. The efficacy of E19 was evaluated in liquid eggs inoculated with S. Enteritidis at 4 and 25 °C, and results showed that it could effectively eradicate S. Enteritidis in just 30 min and prevented its growth up to 72 h. Our findings indicate that E19 can be an alternative to a preservative to control Salmonella in food samples and help prevent and treat salmonellosis.


Asunto(s)
Genoma Viral , Especificidad del Huésped , Fagos de Salmonella , Salmonella enterica , Fagos de Salmonella/genética , Fagos de Salmonella/fisiología , Fagos de Salmonella/aislamiento & purificación , Salmonella enterica/virología , Salmonella enterica/genética , Animales , Salmonella enteritidis/virología , Salmonella enteritidis/genética , Secuenciación Completa del Genoma , Huevos/microbiología , Huevos/virología , Composición de Base
16.
Vet Anim Sci ; 25: 100367, 2024 Sep.
Artículo en Inglés | MEDLINE | ID: mdl-38947184

RESUMEN

The emergence of Salmonella enterica serovars that produce extended-spectrum beta-lactamase and exhibit multi-drug resistance (MDR) poses a substantial global threat, contributing to widespread foodborne illnesses and presenting an alarming issue for public health. This study specifically concentrated on the isolation and identification of ESBL-resistant genes (bla TEM, bla SHV, bla CTX-M1, bla CTX-M2, bla CTX-M9, MultiCase ACC, MultiCase MOX, MultiCase DHA, bla OXA) and the antibiogram profiling of Salmonella enterica serovars found in goat meat samples procured from retail outlets in Bangladesh. During the research in the Sylhet district of Bangladesh, researchers gathered a total of 210 samples of goat meat from 13 different Upazilas. Primarily, cultural and biochemical methods were used for isolation of bacteria from the selected samples. Salmonella enterica serovars Typhimurium and Enteritidis, along with three ESBL-resistant genes, were identified through polymerase chain reactions (PCRs). The disk diffusion test was used to determine antimicrobial susceptibilities. Out of 210 samples analysed, Salmonella spp. was detected in 18.10 % (38 out of 210), with S. Enteritidis and S. Typhimurium found in 9.05 % (19 out of 210) and 5.24 % (11 out of 210) of the samples, respectively. A total of 72.73 % (8/11) of S. Enteritidis and 100 % (19/19) of S. Typhimurium isolates were positive by Multidrug-resistant patterns. The positive outcomes were found of S. Typhimurium tested 63.16 % (12 out of 19) for the bla TEM gene and 21.05 % (4/19) for the bla SHV, gene. The study proposes that the retail goat meat market channel could be a prominent transmission way of ESBL-producing MDR Salmonella enterica serovars, representing a significant public health hazard.

17.
Int Microbiol ; 2024 Jul 08.
Artículo en Inglés | MEDLINE | ID: mdl-38977514

RESUMEN

This study explored the extracellular metabolomic responses of three different Salmonella enterica serotype Typhimurium (S. Typhimurium) strains-ATCC 13311 (STy1), NCCP 16964 (STy4), and NCCP 16958 (STy8)-cultured at refrigeration temperatures. The objective was to identify the survival mechanisms of S. Typhimurium under cold stress by analyzing variations in their metabolomic profiles. Qualitative and quantitative assessments identified significant metabolite alterations on day 6, marking a critical inflection point. Key metabolites such as trehalose, proline, glycerol, and tryptophan were notably upregulated in response to cold stress. Through multivariate analyses, the strains were distinguished using three metabolites-4-aminobutyrate, ethanol, and uridine-as potential biomarkers, underscoring distinct metabolic responses to refrigeration. Specifically, STy1 exhibited unique adaptive capabilities through enhanced metabolism of betaine and 4-aminobutyrate. These findings highlight the variability in adaptive strategies among S. Typhimurium strains, suggesting that certain strains may possess more robust metabolic pathways for enhancing survival in refrigerated conditions.

18.
Cureus ; 16(6): e62050, 2024 Jun.
Artículo en Inglés | MEDLINE | ID: mdl-38989365

RESUMEN

Background Salmonella enterica is a significant foodborne pathogen that causes considerable illness and death in humans and animals. The clustered regularly interspaced short palindromic repeat (CRISPR)-CRISPR-associated protein (Cas) system in bacteria acts as an adaptive immune defense against invasive genetic elements by incorporating short intergenic spacers (IGSs) into CRISPR loci. These loci serve as molecular records of past interactions with phages and plasmids, providing insights into the transmission and evolution of bacterial strains across different hosts. Aim This study aimed to investigate the diversity of IGSs in the CRISPR-1 locus of S. enterica isolates from humans and camels. The objective was to assess the potential of IGSs to distinguish strains, track sources, and understand patterns of zoonotic transmission. Materials and methods Genomic DNA was extracted from multiple strains of S. enterica, and the CRISPR-1 locus was polymerase chain reaction (PCR) amplified and sequenced. The sequences were compared to identify distinct patterns of IGSs and potential host-specific characteristics. Sanger sequencing and bioinformatics tools were used to classify the IGSs and determine their similarity to known sequences in the National Center for Biotechnology Information (NCBI) database. Results Sequence analysis revealed five distinct CRISPR-1 types among S. enterica isolates from humans and three among camel isolates. The presence of shared IGSs between human and camel S. enterica isolates suggested zoonotic or reverse-zoonotic transmission events. Additionally, host-specific unknown IGSs (UIGS) were identified. Importantly, camel isolates initially identified as S. enterica subspecies enterica serovar Enteritidis based on rrnH gene sequencing were reclassified as S. enterica serovar Enteritidis based on CRISPR-1 profiling, demonstrating the higher resolution of CRISPR-based genotyping. Conclusion The diversity of IGSs in the CRISPR-1 locus effectively differentiated S. enterica strains and provided insights into their evolutionary origins and transmission dynamics. CRISPR-based genotyping proves to be a promising tool to complement traditional serotyping methods, enhancing the molecular epidemiology of salmonellosis and potentially leading to better management and control strategies for this pathogen.

19.
Animals (Basel) ; 14(13)2024 Jul 02.
Artículo en Inglés | MEDLINE | ID: mdl-38998064

RESUMEN

Intestinal infections caused by Escherichia coli and Salmonella enterica pose a huge economic burden on the swine industry that is exacerbated by the development of antimicrobial resistance in these pathogens, thus raising the need for alternative prevention and treatment methods. Our aim was to test the beneficial effects of the flavonoid luteolin in an in vitro model of porcine intestinal infections. We infected the porcine intestinal epithelial cell line IPEC-J2 with E. coli and S. enterica subsp. enterica serovar Typhimurium (106 CFU/mL) with or without previous, concurrent, or subsequent treatment with luteolin (25 or 50 µg/mL), and measured the changes in the reactive oxygen species and interleukin-6 and -8 levels of cells. We also tested the ability of luteolin to inhibit the adhesion of bacteria to the cell layer, and to counteract the barrier integrity damage caused by the pathogens. Luteolin was able to alleviate oxidative stress, inflammation, and barrier integrity damage, but it could not inhibit the adhesion of bacteria to IPEC-J2 cells. Luteolin is a promising candidate to be used in intestinal infections of pigs, however, further studies are needed to confirm its efficacy. The use of luteolin in the future could ultimately lead to a reduced need for antibiotics in pig production.

20.
Food Microbiol ; 123: 104586, 2024 Oct.
Artículo en Inglés | MEDLINE | ID: mdl-39038892

RESUMEN

Wood is reportedly more difficult to maintain in hygienic condition versus other food contact materials, yet its use in produce packing and retail warrants efforts to reduce the risk of microbial pathogen contamination and attachment. This study characterized antifouling capabilities of fluorinated silanes applied to wood used in fresh edible produce handling to render the wood superhydrophobic and less supportive of bacterial pathogen attachment. Pine and oak cubic coupon surfaces were treated with 1% (w/w) silane or left untreated. Treated and untreated coupons were inoculated with Salmonella enterica or Listeria monocytogenes and held to facilitate pathogen attachment for 1, 4, or 8 h. Silane treatment of wood produced significant reductions in the proportions of strongly attaching cells for both pathogens versus loosely attaching cells (P < 0.01). Salmonella attachment demonstrated a dependency on wood treatment; silane-treated wood supported a lower fraction of strongly adhering cells (1.87 ± 1.24 log CFU/cm2) versus untreated wood (3.72 ± 0.67 log CFU/cm2). L. monocytogenes demonstrated significant declines in strongly attaching cells during extended exposure to silane-treated wood, from 7.59 ± 0.14 to 5.27 ± 0.68 log CFU/cm2 over 8 h post-inoculation. Microscopic analysis demonstrated silane treatment increased the surface roughness of both woods, leading to superhydrophobic conditions on wood surfaces, consequently decreasing strong attachment of pathogenic bacteria.


Asunto(s)
Adhesión Bacteriana , Interacciones Hidrofóbicas e Hidrofílicas , Listeria monocytogenes , Salmonella enterica , Silanos , Madera , Madera/microbiología , Madera/química , Listeria monocytogenes/efectos de los fármacos , Listeria monocytogenes/crecimiento & desarrollo , Listeria monocytogenes/fisiología , Adhesión Bacteriana/efectos de los fármacos , Salmonella enterica/efectos de los fármacos , Salmonella enterica/crecimiento & desarrollo , Humanos , Silanos/farmacología , Silanos/química , Microbiología de Alimentos , Contaminación de Alimentos/prevención & control , Contaminación de Alimentos/análisis , Embalaje de Alimentos/métodos , Recuento de Colonia Microbiana , Quercus/microbiología , Quercus/química , Pinus/microbiología
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