RESUMEN
Salmonella is a rod-shaped gram-negative bacterium of the family Enterobacteriaceae, commonly present in the gastrointestinal tract in humans and animals. Salmonella-associated bacteriuria and prostatitis are rare but have been reported in humans, predominantly older patients with underlying diseases, including urinary tract obstructions, diabetes mellitus, and compromised immunity. In dogs, Salmonella bacteriuria and prostatitis have only been described in patients on immunosuppressive medications. This study reports the case of a 7 yr old male Pit bull terrier mix with Salmonella prostatitis. The patient had a 3 day history of lethargy and anorexia. He was fed a commercial diet and had no previous medical or medication history. On physical examination, he had caudal abdominal pain and a firm, enlarged, painful prostate. Ultrasound revealed marked prostatomegaly with multifocal echogenic fluid-filled cavitations and regional peritonitis. Urine and prostatic fluid culture grew Salmonella (>100,000 colony-forming units/mL) using standard culture methods. Treatment with enrofloxacin was initiated for 8 wk. Repeat urine and prostatic cultures after cessation of antibiotics were negative, and serial fecal cultures were Salmonella negative. This case report is, to the best of our knowledge, the first to describe Salmonella prostatitis and bacteriuria in an immunocompetent dog who was not fed a raw diet.
Asunto(s)
Antibacterianos , Enfermedades de los Perros , Prostatitis , Salmonelosis Animal , Salmonella enteritidis , Perros , Animales , Masculino , Enfermedades de los Perros/microbiología , Enfermedades de los Perros/tratamiento farmacológico , Prostatitis/veterinaria , Prostatitis/microbiología , Prostatitis/tratamiento farmacológico , Salmonella enteritidis/aislamiento & purificación , Salmonelosis Animal/microbiología , Salmonelosis Animal/tratamiento farmacológico , Antibacterianos/uso terapéutico , Enrofloxacina/uso terapéuticoRESUMEN
Quantification of trace amounts of proteins is technically challenging because proteins cannot be directly amplified like nucleic acids. To improve the analytical sensitivity and to complement conventional protein analysis methods, we developed a highly sensitive and homogeneous detection strategy called Protein-Induced DNA Dumbbell Amplification (PINDA). PINDA combines protein recognition with exponential nucleic acid amplification by using protein binding probes made of DNA strands conjugated to protein affinity ligands. When a pair of probes bind to the same target protein, complementary nucleic acid sequences that are conjugated to each probe are brought into close proximity. The increased local concentration of the probes results in the formation of a stable dumbbell structure of the nucleic acids. The DNA dumbbell is readily amplifiable exponentially using techniques such as loop-mediated isothermal amplification. The PINDA assay eliminates the need for washing or separation steps, and is suitable for on-site applications. Detection of the model protein, thrombin, has a linear range of 10 fM-100 pM and detection limit of 10 fM. The PINDA technique is successfully applied to the analysis of dairy samples for the detection of ß-lactoglobulin, a common food allergen, and Salmonella enteritidis, a foodborne pathogenic bacterium. The PINDA assay can be easily modified to detect other targets by changing the affinity ligands used to bind to the specific targets.
Asunto(s)
Técnicas Biosensibles , ADN , Técnicas de Amplificación de Ácido Nucleico , Técnicas de Amplificación de Ácido Nucleico/métodos , Técnicas Biosensibles/métodos , ADN/química , ADN/genética , Salmonella enteritidis/aislamiento & purificación , Salmonella enteritidis/genética , Trombina/análisis , Límite de Detección , Lactoglobulinas/análisis , Lactoglobulinas/química , Contaminación de Alimentos/análisis , Humanos , Animales , Análisis de los Alimentos/métodos , Leche/química , Leche/microbiología , Microbiología de AlimentosRESUMEN
BACKGROUND: Bacteriophage has been renewed attention as a new antibacterial agent due to the limitations of antibiotic treatment. Bacteriophages are generally thought to be highly host specific and even strain specific, but a small number of polyvalent bacteriophages have been found to infect bacteria of different genera. RESULTS: In this study, a virulent lytic bacteriophage (named Salmonella phage PSH-1) of Salmonella Enteritidis was isolated from the sewage samples of a large-scale pig farm, PSH-1 demonstrated lytic activity against four multidrug-resistant Salmonella Enteritidis isolates and Escherichia coli, and then its biological characteristics, genome and bacteriostatic ability were investigated. The results showed that the initial titer of PSH-1 was 1.15 × 1010 PFU/mL and the optimal multiplicity of infection (MOI) was 0.01, PSH-1 has stable activity in the range of pH 3.0-11.0. One-step growth curve showed that its latent period was 20 min, burst time was 80 min, and the burst was 495 particles. The whole-genome sequencing results revealed phage PSH-1 had a linear dsDNA with 48,466 bp length. The G/C content was 45.33%. Non-coding RNA genes and virulence factors were not found. Eighty- five open reading frames (ORFs) were identified after online annotation. By tests, the use of phage could succeed in controlling the artificial Salmonella contamination in milk at a range of temperatures. CONCLUSIONS: This study reports a novel Salmonella Enteritidis phage PSH-1, which has a robust lytic ability, no virulence factors, and good stability. The characterization and genomic analysis of PSH-1 will develop our understanding of phage biology and diversity and provide a potential arsenal for controlling of salmonellosis.
Asunto(s)
Farmacorresistencia Bacteriana Múltiple , Genoma Viral , Fagos de Salmonella , Salmonella enteritidis , Aguas del Alcantarillado , Secuenciación Completa del Genoma , Salmonella enteritidis/virología , Salmonella enteritidis/genética , Salmonella enteritidis/efectos de los fármacos , Fagos de Salmonella/genética , Fagos de Salmonella/aislamiento & purificación , Fagos de Salmonella/fisiología , Fagos de Salmonella/clasificación , Farmacorresistencia Bacteriana Múltiple/genética , Animales , Aguas del Alcantarillado/virología , Aguas del Alcantarillado/microbiología , Porcinos , Composición de Base , Escherichia coli/virología , Escherichia coli/genéticaRESUMEN
Probiotics are live microorganisms that, when administered in adequate quantities, provide health benefits to the host. In this study, phenotypic and genotypic methods were used to evaluate the probiotic properties of Bacillus altitudinis 1.4. The isolate was sensitive to all antimicrobials tested and presented a positive result in the hemolysis test. B. altitudinis 1.4 spores were more resistant than vegetative cells, when evaluated in simulation of cell viability in the gastrointestinal tract, as well as adhesion to the intestinal mucosa. The isolate was capable of self-aggregation and coaggregation with pathogens such as Escherichia coli ATCC 25922 and Salmonella Enteritidis ATCC 13076. Genomic analysis revealed the presence of genes with probiotic characteristics. From this study it was possible to evaluate the gene expression of pro-inflammatory and anti-inflammatory cytokines for different treatments. Viable vegetative cells of B. altitudinis 1.4 increased the transcription of pro-inflammatory factors, in addition to also increasing the transcription of IL-10, indicating a tendency to stimulate a pro-inflammatory profile. Given the results presented, B. altitudinis 1.4 showed potential to be applied in the incorporation of this microorganism into animal feed, since the spores could tolerate the feed handling and pelletization processes.
Asunto(s)
Bacillus , Genoma Bacteriano , Probióticos , Probióticos/farmacología , Bacillus/genética , Factores Inmunológicos/farmacología , Citocinas/metabolismo , Citocinas/genética , Escherichia coli/genética , Esporas Bacterianas/genética , Adhesión Bacteriana , Salmonella enteritidis/genética , Alimentación Animal/microbiología , Antibacterianos/farmacología , AnimalesRESUMEN
Self-powered photoelectrochemical (PEC) sensing is a novel sensing modality. The introduction of dual-mode sensing and photoelectrocatalysis in a self-powered system enables both detection and sterilization purposes. To this end, herein, a self-powered multifunctional platform for the photoelectrochemical-fluorescence (PEC-FL) detection and in-situ inactivation of Salmonella enteritidis (SE) was constructed. The platform utilized Bi4NbO8Cl/V2CTx/FTO as a photoanode and CuInS2/FTO as a photocathode and incubated quantum dot (QDs) signaling probes on the surface of the photocathode. During detection, the system drives the transfer of photogenerated electrons between the dual photoelectrodes through the Fermi energy level difference. The photoanode amplifies the photoelectric signal, while the photocathode is solely dedicated to the immune recognition process. QDs provide an additional fluorescence signal to the system. Under optimal experimental conditions, the multifunctional platform achieves detection limits of 3.2 and 5.3 CFU/mL in PEC and FL modes respectively, with a detection range of 2.91 × 102 to 2.91 × 108 CFU/mL. With the application of an external bias voltage, it further promotes electron transfer between the dual photoelectrodes, inhibits the recombination of photogenerated electrons and holes. It generates a significant amount of superoxide radicals (·O2-) in the cathodic region, resulting in strong sterilization efficiency (99%). The constructed self-powered multifunctional platform exhibits high sensitivity and sterilization efficiency, it provides a feasible and effective strategy to enhance the comprehensive capability of self-powered sensors.
Asunto(s)
Técnicas Biosensibles , Técnicas Electroquímicas , Puntos Cuánticos , Salmonella enteritidis , Salmonella enteritidis/aislamiento & purificación , Puntos Cuánticos/química , Técnicas Biosensibles/instrumentación , Técnicas Electroquímicas/instrumentación , Técnicas Electroquímicas/métodos , Límite de Detección , Electrodos , Humanos , Infecciones por Salmonella/microbiologíaRESUMEN
Synthesis of an antigenic tetrasaccharide repeating unit of the O-polysaccharide of Salmonella enteritidis lipopolysaccharide has been accomplished. Those four monosaccharides were assembled stereoselectively by employing our recently developed cationic gold(I)-catalyzed glycosylation methodology involving various glycosyl N-1,1-dimethylpropargyl carbamate donors. The newly formed α-anomeric stereochemical configuration was controlled by the axial C2-OBz of the glycosyl donors via anchimeric assistance.
Asunto(s)
Carbamatos , Oro , Oligosacáridos , Salmonella enteritidis , Oro/química , Glicosilación , Carbamatos/química , Salmonella enteritidis/química , Catálisis , Oligosacáridos/química , Oligosacáridos/síntesis química , Cationes/química , Antígenos O/química , EstereoisomerismoRESUMEN
Using a solvent-casting method, a poly(lactic acid) (PLA) film incorporated with caprylic acid (CA) was developed as an active packaging against Salmonella enterica ser. Typhimurium and S. enteritidis to reduce the risk of microbial contamination during distribution and storage of meat. According to the minimum inhibitory concentration (MIC) test results of the natural antimicrobial, CA was introduced at 0.6, 1.2, 2.4, and 4.8 % (v/v) into neat PLA. The biofilm inhibitory effect and antimicrobial efficacy of CA-PLA film against both Salmonella strains, as well as the intermolecular interactions and barrier properties of CA-PLA film, were evaluated. Biofilm formation was reduced to below the detection limit (<1.0 log CFU/cm2) for both S. typhimurium and S. enteritidis when co-cultured overnight with 4.8 % CA-PLA film. The 4.8 % CA-PLA film achieved maximum log reductions of 2.58 and 1.65 CFU/g for S. typhimurium and 2.59 and 1.76 CFU/g for S. enteritidis on inoculated chicken breast and beef stored at 25 °C overnight, respectively, without any quality (color and texture) losses. CA maintained its typical chemical structure in the film, as confirmed by attenuated total reflectance-Fourier transform infrared (ATR-FTIR) spectra. Furthermore, film surface morphology observations by field emission scanning electron microscopy (FESEM) showed that CA-PLA film was smoother than neat PLA film. No significant (P > 0.05) changes were observed for water vapor permeability and oxygen permeability by the addition of CA into PLA film, suggesting that CA-PLA film is a promising strategy for active packaging to control Salmonella contamination in the meat industry.
Asunto(s)
Biopelículas , Caprilatos , Embalaje de Alimentos , Carne , Pruebas de Sensibilidad Microbiana , Poliésteres , Salmonella typhimurium , Caprilatos/farmacología , Biopelículas/efectos de los fármacos , Biopelículas/crecimiento & desarrollo , Embalaje de Alimentos/métodos , Poliésteres/farmacología , Poliésteres/química , Carne/microbiología , Animales , Salmonella typhimurium/efectos de los fármacos , Salmonella typhimurium/crecimiento & desarrollo , Bovinos , Pollos , Salmonella enteritidis/efectos de los fármacos , Salmonella enteritidis/crecimiento & desarrollo , Microbiología de Alimentos , Contaminación de Alimentos/prevención & control , Antibacterianos/farmacología , Antiinfecciosos/farmacología , Salmonella/efectos de los fármacos , Salmonella/crecimiento & desarrollo , Polímeros/farmacología , Polímeros/química , Ácido Láctico/farmacologíaRESUMEN
Salmonella enterica subsp. enterica serovar Enteritidis (SE) is a global concern for the poultry industry due to its association with foodborne illnesses. The transmission occurs through the transovarial route which initiates from colonization in oviducts and ascending to ovaries. Though there are studies on cytosine-phosphate-guanine oligodeoxynucleotide (CpG-ODN) and the increase of innate immune response, there is limited research on the intravaginal treatment using CpG-ODN. Previous studies have shown that stimulating CpG-ODN can induce the production of antimicrobial peptide avian beta-defensins (AvBDs) in vaginal cell cultures, there is limited information on the use of intravaginal treatment to induce the innate immune system, particularly in the Kampung Unggul Balitbangtan (KUB-1) chickens (Gallus gallus domesticus). This study investigates the impact of intravaginal CpG-ODN stimulation on the innate immune response in KUB-1 chicken ovaries and oviducts when challenged to SE. A total of 39 KUB-1 chickens were divided into four groups namely T1 (treated with CpG-ODN, n=12), T2 (SE group, n=12), T3 (CpG-ODN and SE, n=12), and Control (without CpG-ODN and SE, n=3). Chickens were observed from day 1 to 4 post-intravaginal (PI) inoculation. The results suggest that intravaginal CpG-ODN treatment modulates AvBD10 production through toll-like receptor (TLR)21, with interleukin (IL)1B and IL10 playing reciprocal roles, providing insights into the potential of this treatment to prevent transovarial Salmonellosis in poultry. The novelty of this study adds valuable insights to the current body of knowledge.
Asunto(s)
Pollos , Citocinas , Oligodesoxirribonucleótidos , Enfermedades de las Aves de Corral , Salmonelosis Animal , Salmonella enteritidis , Animales , Oligodesoxirribonucleótidos/farmacología , Femenino , Citocinas/metabolismo , beta-Defensinas/genética , Inmunidad Innata , Ovario , Oviductos , Receptores Toll-Like/genética , Receptores Toll-Like/metabolismo , Vagina/microbiología , Expresión GénicaRESUMEN
Chicken meat is contaminated with Salmonella from the gut of infected chickens during slaughter. Eradication of Salmonella from broiler chickens through hygiene measures and/or vaccination is not cost-effective; complementary approaches are required. A mature gut microbiota obstructs Salmonella infection in chickens, and deliberate fortification of colonization resistance through prebiotic feed formulations would benefit public health and poultry production. Prebiotic galactooligosaccharides hastens Salmonella clearance from the gut of infected chickens. To better understand the role of galactooligosaccharides in colonization resistance, broiler chickens were raised on a wheat-soybean meal-based feed, with or without galactooligosaccharides for the first 24 days of life. Chickens were orally challenged with Salmonella enterica serovar Enteritidis at 20 days and the effect of supplementary galactooligosaccharides characterized by profiling Salmonella colonization, gut microbiota, innate immune response, and cecal short-chain fatty acid concentrations. Exposure to dietary galactooligosaccharides shortened the time to clear S. Enteritidis from the ceca. Differential abundance analysis of the cecal microbiota associated Salmonella challenge with a bacterial taxon belonging to the Acidaminococcaceae family (P < 0.005). Increased cecal concentrations of the short-chain fatty acids propionate and valerate were measured in Salmonella-challenged chickens sustained on either control or galactooligosaccharide-supplemented feed relative to mock-challenged controls; but far greater concentrations were detected in chickens fed a galactooligosaccharide-supplemented diet in early life. The abundance of the Acidaminococcaceae taxon exhibited a positive correlation with the cecal concentrations of propionate (ρ = 0.724, P = 0.008) and valerate (ρ = 0.71, P = 0.013). The absence of cecal pro-inflammatory transcriptional responses suggest that the rapid Salmonella clearance observed for the galactooligosaccharide-supplemented diet was not linked to innate immune function. IMPORTANCE: Work presented here identifies bacterial taxa responsible for colonization resistance to Salmonella in broiler chickens. Deliberate cultivation of these taxa with prebiotic galactooligosaccharide has potential as a straight-forward, safe, and cost-effective intervention against Salmonella. We hypothesize that catabolism of galactooligosaccharide and its breakdown products by indigenous microorganisms colonizing the chicken gut produce excess levels of propionate. In the absence of gross inflammation, propionate is inimical to Salmonella and hastens intestinal clearance.
Asunto(s)
Alimentación Animal , Pollos , Microbioma Gastrointestinal , Oligosacáridos , Prebióticos , Salmonelosis Animal , Salmonella enteritidis , Animales , Pollos/microbiología , Pollos/inmunología , Prebióticos/administración & dosificación , Microbioma Gastrointestinal/efectos de los fármacos , Oligosacáridos/administración & dosificación , Oligosacáridos/farmacología , Salmonelosis Animal/prevención & control , Salmonelosis Animal/microbiología , Salmonelosis Animal/inmunología , Alimentación Animal/análisis , Enfermedades de las Aves de Corral/microbiología , Enfermedades de las Aves de Corral/prevención & control , Enfermedades de las Aves de Corral/inmunología , Ciego/microbiología , Ciego/metabolismoRESUMEN
Salmonella is a zoonotic pathogen posing a serious risk to the farming industry and public health due to food animals serving as reservoirs for future contamination and spread of Salmonella. The present study is designed to monitor the contamination status of Salmonella in duck farms and the main control points during breeding. 160 strains of duck-derived Salmonella were isolated from the 736 samples (cloacal swabs, feces, water, feed, soil, air and dead duck embryos) collected in southwest Shandong Province and the province's surrounding area. The percentage of Salmonella-positive samples collected was 21.74 % (160/736), and the greatest prevalence from duck embryo samples (40.00 %, 36/90). These Salmonella were classified into 23 serotypes depending on their O and H antigens, in which S. Typhimurium (30.15 %), S. Kottbus (13.97 %) and S. Enteritidis (10.29 %) were the prevailing serotypes. Subsequently, the molecular subtyping was done. Clustered regularly interspaced short palindromic repeats (CRISPR) analysis showed that 41 strains of S. Typhimurium and 14 strains of S. Enteritidis were classified into 13 and 3 genotypes, respectively. 19 S. Kottbus isolates from different sources featured ST1546, ST198, ST321, and ST1690 by multilocus sequence typing (MLST) analysis, among which ST1546 belongs to S. Kottbus was a new ST. The minimum spanning tree analysis based on the two CRISPR loci and seven MLST loci from all S. Typhimurium, S. Enteritidis and S. Kottbus isolates revealed that duck embryos, feed and water were key control points to the spread of Salmonella along the breeding chain. Meanwhile, the emergence of S. Kottbus in duck flocks was considered a potential public health hazard.
Asunto(s)
Patos , Granjas , Heces , Genotipo , Enfermedades de las Aves de Corral , Salmonelosis Animal , Salmonella , Serogrupo , Animales , Patos/microbiología , China/epidemiología , Salmonelosis Animal/microbiología , Salmonelosis Animal/epidemiología , Salmonella/genética , Salmonella/aislamiento & purificación , Salmonella/clasificación , Enfermedades de las Aves de Corral/microbiología , Enfermedades de las Aves de Corral/epidemiología , Heces/microbiología , Salmonella typhimurium/genética , Salmonella typhimurium/aislamiento & purificación , Salmonella typhimurium/clasificación , Repeticiones Palindrómicas Cortas Agrupadas y Regularmente Espaciadas/genética , Prevalencia , Filogenia , Salmonella enteritidis/genética , Salmonella enteritidis/aislamiento & purificación , Salmonella enteritidis/clasificación , Tipificación de Secuencias Multilocus , SerotipificaciónRESUMEN
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 BaseRESUMEN
Salmonella enterica (S. enterica) is the most common food and waterborne pathogen worldwide. The growing trend of antibiotic-resistant S. enterica poses severe healthcare threats. As an alternative antimicrobial agent, bacteriophage-encoded endolysins (endolysins) are a potential agent in controlling S. enterica infection. Endolysins are enzymes that particularly target the peptidoglycan layer of bacterial cells, leading to their rupture and destruction. However, the application of endolysins against Gram-negative bacteria is limited due to the presence of the outer membrane in the cell wall, which hinders the permeation of externally applied endolysins. This study aimed the prokaryotic expression system to produce the recombinant endolysin ENDO-1252, encoded by the Salmonella bacteriophage-1252 associated with S. Enteritidis. Subsequently, ENDO-1252 had strong lytic activity not only against S. Enteritidis but also against S. Typhimurium. In addition, ENDO-1252 showed optimal thermostability and lytic activity at 25°C with a pH of 7.0. In combination with 0.1 mM EDTA, the effect of 120 µg of ENDO-1252 for 6 hours exhibited the highest lytic activity, resulting in a reduction of 1.15 log or 92.87% on S. Enteritidis. These findings suggest that ENDO-1252 can be used as a potential and innovative antibacterial agent for controlling the growth of S. Enteritidis.
Asunto(s)
Endopeptidasas , Fagos de Salmonella , Salmonella enterica , Endopeptidasas/farmacología , Endopeptidasas/genética , Endopeptidasas/metabolismo , Fagos de Salmonella/genética , Salmonella enterica/efectos de los fármacos , Salmonella enterica/genética , Antibacterianos/farmacología , Salmonella enteritidis/efectos de los fármacos , Salmonella enteritidis/genética , Salmonella enteritidis/crecimiento & desarrolloRESUMEN
BACKGROUND: Salmonellosis is a widespread zoonotic disease that poses a significant threat to livestock and public health. This study aimed to serotype 20 Salmonella isolates obtained from sixty retail chicken meats, assess Salmonella contamination from eggs, and evaluate antibiotic resistance profiles. METHODS AND RESULTS: Twenty eggs were randomly collected in the new Borg El Arab market. Bacterial isolation was carried out utilizing both traditional culture, biochemical, and PCR methods. Among the twenty eggs analyzed, three (15%) tested positive for Salmonella, while the remaining seventeen (85%) were confirmed as negative. Genotyping through multiplex PCR revealed the presence of two S. Enteritidis and other serovar, with the use of three specific gene sets: a random sequence for Salmonella spp., sdfI gene for S. Enteritidis, and flagellin (fliC gene) for S. Typhimurium. Out of the 20 isolates obtained from chicken meat, five (25%) were identified as S. Typhimurium, and three (15%) were classified as S. Enteritidis. All isolates sourced from chicken meat exhibited resistance to Rifampicin and Amoxicillin, with 90% displaying sensitivity to cefotaxime, gemifloxacin, and Erythromycin. Importantly, S. Blegdam, identified via serological methods, displayed resistance to all tested antibiotics. For the three isolates obtained from eggs, 66.6% showed sensitivity to cefotaxime, erythromycin, cefuraxime, and cefaclor, while displaying complete resistance (100%) to Amoxicillin, rifampicin, clarithromycin, and cefadroxil. Notably, one serovar exhibited absolute resistance to all tested drugs. CONCLUSION: Stakeholders must implement strict control measures and rationalize antibiotic use in veterinary and human medicine due to the rise of antibiotic-resistant strains.
Asunto(s)
Antibacterianos , Pollos , Huevos , Microbiología de Alimentos , Reacción en Cadena de la Polimerasa Multiplex , Salmonella enteritidis , Salmonella typhimurium , Salmonella enteritidis/genética , Salmonella enteritidis/efectos de los fármacos , Salmonella enteritidis/aislamiento & purificación , Reacción en Cadena de la Polimerasa Multiplex/métodos , Animales , Egipto , Pollos/microbiología , Salmonella typhimurium/efectos de los fármacos , Salmonella typhimurium/genética , Salmonella typhimurium/aislamiento & purificación , Antibacterianos/farmacología , Huevos/microbiología , Microbiología de Alimentos/métodos , Pruebas de Sensibilidad Microbiana/métodos , Genotipo , Farmacorresistencia Bacteriana/genética , Carne/microbiología , Técnicas de Genotipaje/métodosRESUMEN
Invasive non-typhoidal Salmonella (iNTS) disease is an under-recognized high-burden disease causing major health and socioeconomic issues in sub-Saharan Africa (sSA), predominantly among immune-naïve infants and young children, including those with recognized comorbidities such as HIV infection. iNTS disease is primarily caused by Salmonella enterica serovar Typhimurium sequence type (ST) 313 and 'African-restricted clades' of Salmonella Enteritidis ST11 that have emerged across the African continent as a series of epidemics associated with acquisition of new antimicrobial resistance. Due to genotypes with a high prevalence of antimicrobial resistance and scarcity of therapeutic options, these NTS serovars are designated by the World Health Organization as a priority pathogen for research and development of interventions, including vaccines, to address and reduce NTS associated bacteremia and meningitis in sSA. Novel and traditional vaccine technologies are being applied to develop vaccines against iNTS disease, and the results of the first clinical trials in the infant target population should become available in the near future. The "Vaccine Value Profile" (VVP) addresses information related predominantly to invasive disease caused by Salmonella Enteritidis and Salmonella Typhimurium prevalent in sSA. Information is included on stand-alone iNTS disease candidate vaccines and candidate vaccines targeting iNTS disease combined with another invasive serotype, Salmonella Typhi, that is also common across sSA. Out of scope for the first version of this VVP is a wider discussion on either diarrheagenic NTS disease (dNTS) also associated with Salmonella Enteritidis and Salmonella Typhimurium or the development of a multivalent Salmonella vaccines targeting key serovars for use globally. This VVP for vaccines to prevent iNTS disease is intended to provide a high-level, holistic assessment of the information and data that are currently available to inform the potential public health, economic, and societal value of pipeline vaccines and vaccine-like products. Future versions of this VVP will be updated to reflect ongoing activities such as vaccine development strategies and a "Full Vaccine Value Assessment" that will inform the value proposition of an iNTS disease vaccine. This VVP was developed by a working group of subject matter experts from academia, non-profit organizations, public private partnerships, and multi-lateral organizations, and in collaboration with stakeholders from the World Health Organization African Region. All contributors have extensive expertise on various elements of the iNTS disease VVP and collectively aimed to identify current research and knowledge gaps. The VVP was developed using only existing and publicly available information.
Asunto(s)
Infecciones por Salmonella , Vacunas contra la Salmonella , Salmonella enteritidis , Humanos , África del Sur del Sahara/epidemiología , Salmonella enteritidis/inmunología , Salmonella enteritidis/genética , Salmonella enteritidis/patogenicidad , Infecciones por Salmonella/prevención & control , Infecciones por Salmonella/epidemiología , Infecciones por Salmonella/microbiología , Infecciones por Salmonella/inmunología , Salmonella typhimurium/inmunología , Salmonella typhimurium/patogenicidad , Salmonella typhimurium/genética , Vacunas contra la Salmonella/inmunología , Vacunas contra la Salmonella/administración & dosificaciónRESUMEN
Phage therapy holds promise as an alternative to antibiotics for combating multidrug-resistant bacteria. However, host bacteria can quickly produce progeny that are resistant to phage infection. In this study, we investigated the mechanisms of bacterial resistance to phage infection. We found that Rsm1, a mutant strain of Salmonella enteritidis (S. enteritidis) sm140, exhibited resistance to phage Psm140, which was originally capable of lysing its host at sm140. Whole genome sequencing analysis revealed a single nucleotide mutation at position 520 (C â T) in the rfbD gene of Rsm1, resulting in broken lipopolysaccharides (LPS), which is caused by the replacement of CAG coding glutamine with a stop codon TAG. The knockout of rfbD in the sm140ΔrfbD strain caused a subsequent loss of sensitivity toward phages. Furthermore, the reintroduction of rfbD in Rsm1 restored phage sensitivity. Moreover, polymerase chain reaction (PCR) amplification of rfbD in 25 resistant strains revealed a high percentage mutation rate of 64% within the rfbD locus. We assessed the fitness of four bacteria strains and found that the acquisition of phage resistance resulted in slower bacterial growth, faster sedimentation velocity, and increased environmental sensitivity (pH, temperature, and antibiotic sensitivity). In short, bacteria mutants lose some of their abilities while gaining resistance to phage infection, which may be a general survival strategy of bacteria against phages. This study is the first to report phage resistance caused by rfbD mutation, providing a new perspective for the research on phage therapy and drug-resistant mechanisms.
Asunto(s)
Mutación Puntual , Fagos de Salmonella , Salmonella enteritidis , Salmonella enteritidis/virología , Salmonella enteritidis/fisiología , Salmonella enteritidis/genética , Fagos de Salmonella/fisiología , Fagos de Salmonella/genética , Proteínas Bacterianas/genética , Proteínas Bacterianas/metabolismoRESUMEN
The injectisome encoded by Salmonella pathogenicity island 2 (SPI-2) had been thought to translocate 28 effectors. Here, we used a proteomic approach to characterize the secretome of a clinical strain of invasive non-typhoidal Salmonella enterica serovar Enteritidis that had been mutated to cause hyper-secretion of the SPI-2 injectisome effectors. Along with many known effectors, we discovered the novel SseM protein. sseM is widely distributed among the five subspecies of Salmonella enterica, is found in many clinically relevant serovars, and is co-transcribed with pipB2, a SPI-2 effector gene. The translocation of SseM required a functional SPI-2 injectisome. Following expression in human cells, SseM interacted with five components of the dystrophin-associated protein complex (DAPC), namely, ß-2-syntrophin, utrophin/dystrophin, α-catulin, α-dystrobrevin, and ß-dystrobrevin. The interaction between SseM and ß-2-syntrophin and α-dystrobrevin was verified in Salmonella Typhimurium-infected cells and relied on the postsynaptic density-95/discs large/zonula occludens-1 (PDZ) domain of ß-2-syntrophin and a sequence corresponding to a PDZ-binding motif (PBM) in SseM. A ΔsseM mutant strain had a small competitive advantage over the wild-type strain in the S. Typhimurium/mouse model of systemic disease. This phenotype was complemented by a plasmid expressing wild-type SseM from S. Typhimurium or S. Enteritidis and was dependent on the PBM of SseM. Therefore, a PBM within a Salmonella effector mediates interactions with the DAPC and modulates the systemic growth of bacteria in mice. Furthermore, the ΔsseM mutant strain displayed enhanced replication in bone marrow-derived macrophages, demonstrating that SseM restrains intracellular bacterial growth to modulate Salmonella virulence. IMPORTANCE: In Salmonella enterica, the injectisome machinery encoded by Salmonella pathogenicity island 2 (SPI-2) is conserved among the five subspecies and delivers proteins (effectors) into host cells, which are required for Salmonella virulence. The identification and functional characterization of SPI-2 injectisome effectors advance our understanding of the interplay between Salmonella and its host(s). Using an optimized method for preparing secreted proteins and a clinical isolate of the invasive non-typhoidal Salmonella enterica serovar Enteritidis strain D24359, we identified 22 known SPI-2 injectisome effectors and one new effector-SseM. SseM modulates bacterial growth during murine infection and has a sequence corresponding to a postsynaptic density-95/discs large/zonula occludens-1 (PDZ)-binding motif that is essential for interaction with the PDZ-containing host protein ß-2-syntrophin and other components of the dystrophin-associated protein complex (DAPC). To our knowledge, SseM is unique among Salmonella effectors in containing a functional PDZ-binding motif and is the first bacterial protein to target the DAPC.
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Proteínas Bacterianas , Salmonella enteritidis , Animales , Proteínas Bacterianas/metabolismo , Proteínas Bacterianas/genética , Humanos , Ratones , Virulencia , Salmonella enteritidis/genética , Salmonella enteritidis/metabolismo , Salmonella enteritidis/patogenicidad , Factores de Virulencia/metabolismo , Factores de Virulencia/genética , Infecciones por Salmonella/microbiología , Proteínas Asociadas a la Distrofina/metabolismo , Proteínas Asociadas a la Distrofina/genética , Islas Genómicas , Salmonella typhimurium/genética , Salmonella typhimurium/metabolismo , Salmonella typhimurium/patogenicidad , Proteómica , Modelos Animales de Enfermedad , Proteínas de la Membrana/metabolismo , Proteínas de la Membrana/genéticaRESUMEN
Salmonella, a prominent foodborne pathogen, has posed enduring challenges to the advancement of food safety and global public health. The escalating concern over antibiotic misuse, resulting in the excessive presence of drug residues in animal-derived food products, necessitates urgent exploration of alternative strategies for Salmonella control. Bacteriophages emerge as promising green biocontrol agents against pathogenic bacteria. This study delineates the identification of two novel virulent Salmonella phages, namely phage vB_SalS_ABTNLsp11241 (referred to as sp11241) and phage 8-19 (referred to as 8-19). Both phages exhibited efficient infectivity against Salmonella enterica serotype Enteritidis (SE). Furthermore, this study evaluated the effectiveness of two phages to control SE in three different foods (whole chicken eggs, raw chicken meat, and lettuce) at different MOIs (1, 100, and 10000) at 4°C. It's worth noting that sp11241 and 8-19 achieved complete elimination of SE on eggs after 3 h and 6 h at MOI = 100, and after 2 h and 5 h at MOI = 10000, respectively. After 12 h of treatment with sp11241, a maximum reduction of 3.17 log10 CFU/mL in SE was achieved on raw chicken meat, and a maximum reduction of 3.00 log10 CFU/mL was achieved on lettuce. Phage 8-19 has the same effect on lettuce as sp11241, but is slightly less effective than sp11241 on chicken meat (a maximum 2.69 log10 CFU/mL reduction). In conclusion, sp11241 and 8-19 exhibit considerable potential for controlling Salmonella contamination in food at a low temperature and represent viable candidates as green antibacterial agents for food applications.
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Pollos , Huevos , Microbiología de Alimentos , Lactuca , Carne , Fagos de Salmonella , Salmonella enteritidis , Lactuca/microbiología , Animales , Huevos/microbiología , Huevos/virología , Pollos/microbiología , Salmonella enteritidis/virología , Carne/microbiología , Inocuidad de los Alimentos , Contaminación de Alimentos/prevención & control , VirulenciaRESUMEN
Gastroenteritis infection is a major public health concern worldwide, especially in developing countries due to the high annual mortality rate. The antimicrobial and antibiofilm activity of human mesenchymal stem cell-derived conditioned medium (hMSCsCM) encapsulated in chitosan nanoparticles (ChNPs) was studied in vitro and in vivo against common gastroenteritis bacteria. The synthesized ChNPs were characterized using Zeta potential, scanning electron microscopy (SEM), and dynamic light scattering (DLS) techniques. HMSC-derived conditioned medium incorporated into chitosan NPs (hMSCsCM-ChNPs) composite was fabricated by chitosan nanoparticles loaded with BM-MSCs (positive for CD73 and CD44 markers). The antimicrobial and antibiofilm activity of composite was investigated against four common gastroenteritis bacteria (Campylobacter jejuni ATCC29428, Salmonella enteritidis ATCC13076, Shigella dysenteriae PTCC1188, and E. coli ATCC25922) in-vitro and in-vivo. Majority of ChNPs (96%) had an average particle size of 329 nm with zeta potential 7.08 mV. The SEM images confirmed the synthesis of spherical shape for ChNPs and a near-spherical shape for hMSCsCM-ChNPs. Entrapment efficiency of hMSCsCM-ChNPs was 75%. Kinetic profiling revealed that the release rate of mesenchymal stem cells was reduced following the pH reduction. The antibacterial activity of hMSCsCM-ChNPs was significantly greater than that of hMSCsCM and ChNPs at dilutions of 1:2 to 1:8 (P < 0.05) against four common gastroenteritis bacteria. The number of bacteria present decreased more significantly in the group of mice treated with the hMSCsCM-ChNPs composite than in the groups treated with hMSCsCM and ChNPs. The antibacterial activity of hMSCsCM against common gastroenteritis bacteria in an in vivo assay decreased from > 106 CFU/ml to approximately (102 to 10) after 72 h. Both in vitro and in vivo assays demonstrated the antimicrobial and antibiofilm activities of ChNPs at a concentration of 0.1% and hMSCsCM at a concentration of 1000 µg/ml to be inferior to that of hMSCsCM-ChNPs (1000 µg/ml + 0.1%) composite. These results indicated the existence of a synergistic effect between ChNPs and hMSCsCM. The designed composite exhibited notable antibiofilm and antibacterial activities, demonstrating optimal release in simulated intestinal lumen conditions. The utilization of this composite is proposed as a novel treatment approach to combat gastroenteritis bacteria in the context of more challenging infections.
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Antibacterianos , Quitosano , Gastroenteritis , Células Madre Mesenquimatosas , Células Madre Mesenquimatosas/citología , Células Madre Mesenquimatosas/metabolismo , Células Madre Mesenquimatosas/efectos de los fármacos , Quitosano/química , Quitosano/farmacología , Humanos , Animales , Medios de Cultivo Condicionados/farmacología , Ratones , Antibacterianos/farmacología , Antibacterianos/química , Gastroenteritis/microbiología , Pruebas de Sensibilidad Microbiana , Nanopartículas/química , Campylobacter jejuni/efectos de los fármacos , Salmonella enteritidis/efectos de los fármacos , Biopelículas/efectos de los fármacos , Escherichia coli/efectos de los fármacos , Shigella dysenteriae/efectos de los fármacos , Nanoestructuras/química , Tamaño de la PartículaRESUMEN
INTRODUCTION: Salmonella is one of the most common causes of food-borne outbreaks and infection worldwide. Non-typhoidal Salmonella (NTS) infections are common and remain a significant public health problem among important bacterial foodborne diseases. The current study aimed to establish the Non typhoidal Salmonella infection and antimicrobial resistance status among selected patients at Morogoro Regional Referral Hospital (MRRH), Morogoro Region, Tanzania, to inform clinical care management and public health interventions. METHODOLOGY: A cross-sectional study was conducted using medical records and samples were collected from hospitalised and outpatients between October and December 2021. A total of 153 participants were enrolled in the study and 132 consented to being sampled. The collected samples were analysed using standard microbiological techniques. The isolates were subjected to molecular genotyping, where Polymerase Chain Reaction (PCR) was performed targeting the 16S rDNA gene. PCR products were then submitted for sequencing to establish phylogenetic relatedness. Antimicrobial susceptibility testing and resistance genes screening were also conducted. RESULTS: The phylogenetic analysis identified two Salmonella serovars; Salmonella Enteritidis and Salmonella Typhimurium. The isolates were from four adults and seven children patients. The isolates were tested against six antimicrobial agents: tetracycline, trimethoprim, gentamycin, ciprofloxacin, ampicillin and cefotaxime. Further antimicrobial assays were performed by screening 10 antimicrobial resistance genes using PCR. Overall, the highest resistance was observed in ampicillin (100%), whereas the lowest resistance was recorded for ciprofloxacin and gentamicin (9.1%). In addition, four (36.4%) of the isolates were resistant to cefotaxime and three (27.3%) to tetracycline and trimethoprim. The isolates also exhibit the presence of resistance genes for sulfamethoxazole 1&2, tetracycline (tet) A&B, Beta-lactamase CTXM, Beta-lactamase TEM, Beta-lactamase SHV, Gentamycine, Acra and acc3-1 in different occurrences. The overall prevalence of Salmonella species in Morogoro region was 8.3% (11/132) with Salmonella Enteritidis and Salmonella Typhimurium being the only serovars detected from adults and children stool samples. CONCLUSION: Our investigation showed that both children and adults had been exposed to Salmonella spp. However, the occurrence of NTS was higher in children (5.3% (7/132) compared to adults (3.0% (4/132). To stop zoonotic infections and the development of antimicrobial resistance in the community, this calls for Infection Prevention and Control (IPC) and stewardship programmes on rational use of antimicrobials in both health facilities and at the community level.
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Antibacterianos , Infecciones por Salmonella , Humanos , Tanzanía/epidemiología , Infecciones por Salmonella/microbiología , Infecciones por Salmonella/epidemiología , Adulto , Niño , Femenino , Masculino , Estudios Transversales , Preescolar , Antibacterianos/farmacología , Adolescente , Adulto Joven , Persona de Mediana Edad , Pruebas de Sensibilidad Microbiana , Lactante , Filogenia , Salmonella/genética , Salmonella/efectos de los fármacos , Salmonella/clasificación , Salmonella/aislamiento & purificación , Salmonella enteritidis/genética , Salmonella enteritidis/efectos de los fármacos , Salmonella enteritidis/aislamiento & purificación , Salmonella enteritidis/clasificación , Enfermedades Gastrointestinales/microbiología , Enfermedades Gastrointestinales/epidemiología , Salmonella typhimurium/efectos de los fármacos , Salmonella typhimurium/genética , Salmonella typhimurium/aislamiento & purificación , Anciano , Farmacorresistencia BacterianaRESUMEN
The poultry-housing environment plays a significant role in the transmission and persistence of the egg-associated pathogen Salmonella Enteritidis in laying flocks. The commercial egg industry is in the midst of a transition toward cage-free housing, but the food safety ramifications of this shift are not yet certain. The present study assessed internal organ colonization by Salmonella Enteritidis in layer pullets reared in cage-free housing and infected at two different ages. Groups of 280 pullets were transferred from the rearing facility (at 9 wk of age in one trial and 15 wk in another) to a containment facility with four isolation rooms simulating commercial cage-free barns with perches and nest boxes (70 birds/room). Twenty-four pullets in each room were orally inoculated with Salmonella Enteritidis immediately after placement in the containment facility. At 1-2 wk postinoculation in each trial, samples of liver, spleen, and intestinal tract were collected from all birds in two rooms for bacteriologic culturing to detect Salmonella Enteritidis. At 21-22 wk of age, samples of spleen, ovary, and intestinal tract were similarly collected and tested from all birds in the remaining two rooms. Among samples collected at 1-2 wk postinoculation, Salmonella Enteritidis was isolated significantly more often from groups of pullets infected initially at 15 wk of age than from those infected at 9 wk (61% vs. 38% of livers, 59% vs. 31% of spleens, and 84% vs. 57% of intestines). Among samples collected at 21-22 wk of age, the frequency of recovery of Salmonella Enteritidis was again significantly greater in birds infected at 15 wk of age than in those infected at 9 wk (16% vs. 6% of spleens, 9% vs. 1% of ovaries, and 26% vs. 10% of intestines). These data suggest that Salmonella Enteritidis infections introduced into flocks during the later stages of pullet rearing have greater potential to persist into the early phase of egg production.
Nota de investigación- Colonización de órganos internos por Salmonella Enteritidis en pollitas de postura infectadas en dos edades diferentes durante la crianza en alojamiento sin jaulas. El ambiente en alojamientos avícolas juega un papel importante en la transmisión y persistencia del patógeno asociado a los huevos Salmonella Enteritidis en parvadas postura. La industria comercial del huevo se encuentra en medio de una transición hacia alojamientos sin jaulas, pero las ramificaciones de este cambio en la seguridad alimentaria aún no están determinadas. El presente estudio evaluó la colonización de órganos internos por Salmonella Enteritidis en pollitas de postura criadas en alojamientos sin jaulas e infectadas a dos edades diferentes. Se transfirieron grupos de 280 pollitas desde las instalaciones de cría (a las 9 semanas de edad en un ensayo y a las 15 semanas en un segundo ensayo) a una instalación de contención con cuatro salas de aislamiento que simulaban alojamientos comerciales sin jaulas con perchas y nidos (70 aves/sala). Veinticuatro pollitas en cada sala fueron inoculadas oralmente con Salmonella Enteritidis inmediatamente después de su colocación en la instalación de contención. En cada ensayo, de una a dos semanas después de la inoculación, se recolectaron muestras de hígado, bazo y tracto intestinal para cultivo bacteriológico de todas las aves en dos salas para detectar Salmonella Enteritidis. A las 21-22 semanas de edad, se recolectaron y analizaron de manera similar muestras de bazo, ovario y tracto intestinal de todas las aves en las dos salas restantes. Entre las muestras recolectadas entre una y dos semanas después de la inoculación, Salmonella Enteritidis se aisló significativamente con mayor frecuencia en grupos de pollitas infectadas inicialmente a las 15 semanas de edad que en aquellas infectadas a las 9 semanas (61% contra 38 % en los hígados, 59% contra 31% de bazos y 84 % contra 57% en intestinos). Entre las muestras recolectadas a las 21-22 semanas de edad, la frecuencia de recuperación de Salmonella Enteritidis fue nuevamente significativamente mayor en aves infectadas a las 15 semanas de edad que en aquellas infectadas a las 9 semanas (16% contra 6% de bazos, 9% contra 1% en ovarios y 26% contra 10% de los intestinos). Estos datos sugieren que las infecciones por Salmonella Enteritidis introducidas en las parvadas durante las últimas etapas de la cría de pollitas tienen un mayor potencial para persistir en la fase inicial de la producción de huevos.