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1.
Sci Rep ; 12(1): 10555, 2022 Jun 22.
Artigo em Inglês | MEDLINE | ID: mdl-35732677

RESUMO

Salmonella Dublin is a cattle-associated serovar sporadically causing disease in humans. S. Dublin strains isolated in Brazil and in other countries were analyzed to determine their phylogenetic relationships, the presence of genes, plasmids, genomic regions related to virulence and antimicrobial resistance genes repertoire, using WGS analyses. Illumina was used to sequence the genome of 112 S. Dublin strains isolated in Brazil from humans (n = 82) and animals (n = 30) between 1983 and 2016. Furthermore, 87 strains from other countries were analyzed. WGSNP analysis revealed three different clades, in which the strains from Brazil belonged to two clades, A and C. Most of the genes and genomic regions searched varied among the strains studied. The siderophore genes iroB and iroC were exclusively found in strains from Brazil and pegD gene, related to fimbrial adherence determinants, were positive in 124 strains from clades A and B but absent in all the strains from clade C (n = 71). Eleven plasmid replicons were found in the strains from Brazil, and nine were exclusively found in strains from other countries. The antimicrobial resistance genes mdsA and mdsB, that encode an efflux pump, were found in all the strains studied. The strains from Brazil carried other resistance genes, such as tet(A) (n = 11), tet(B) (n = 4) and tet(C) (n = 4), blaTEM-1 (n = 4), catA1 (n = 1), aadA1 (n = 1), and sul1 (n = 1). In conclusion, S. Dublin strains isolated in Brazil presented some few unique genes not found in strains from other countries and were allocated into two distinct clades with strains of human and animal origin epidemiologically related. This fact stresses the zoonotic potential of S. Dublin circulating in Brazil for more than 30 years.


Assuntos
Salmonella enterica , Animais , Antibacterianos/farmacologia , Brasil/epidemiologia , Bovinos , Filogenia , Plasmídeos/genética , Sorogrupo , Sequenciamento Completo do Genoma
2.
PLoS Genet ; 18(6): e1010174, 2022 06.
Artigo em Inglês | MEDLINE | ID: mdl-35653335

RESUMO

Non-typhoidal Salmonella enterica is a common cause of diarrhoeal disease; in humans, consumption of contaminated poultry meat is believed to be a major source. Brazil is the world's largest exporter of chicken meat globally, and previous studies have indicated the introduction of Salmonella serovars through imported food products from Brazil. Here we provide an in-depth genomic characterisation and evolutionary analysis to investigate the most prevalent serovars and antimicrobial resistance (AMR) in Brazilian chickens and assess the impact to public health of products contaminated with S. enterica imported into the United Kingdom from Brazil. To do so, we examine 183 Salmonella genomes from chickens in Brazil and 357 genomes from humans, domestic poultry and imported Brazilian poultry products isolated in the United Kingdom. S. enterica serovars Heidelberg and Minnesota were the most prevalent serovars in Brazil and in meat products imported from Brazil into the UK. We extended our analysis to include 1,259 publicly available Salmonella Heidelberg and Salmonella Minnesota genomes for context. The Brazil genomes form clades distinct from global isolates, with temporal analysis suggesting emergence of these Salmonella Heidelberg and Salmonella Minnesota clades in the early 2000s, around the time of the 2003 introduction of the Enteritidis vaccine in Brazilian poultry. Analysis showed genomes within the Salmonella Heidelberg and Salmonella Minnesota clades shared resistance to sulphonamides, tetracyclines and beta-lactams conferred by sul2, tetA and blaCMY-2 genes, not widely observed in other co-circulating serovars despite similar selection pressures. The sul2 and tetA genes were concomitantly carried on IncC plasmids, whereas blaCMY-2 was either co-located with the sul2 and tetA genes on IncC plasmids or independently on IncI1 plasmids. Long-term surveillance data collected in the UK showed no increase in the incidence of Salmonella Heidelberg or Salmonella Minnesota in human cases of clinical disease in the UK following the increase of these two serovars in Brazilian poultry. In addition, almost all of the small number of UK-derived genomes which cluster with the Brazilian poultry-derived sequences could either be attributed to human cases with a recent history of foreign travel or were from imported Brazilian food products. These findings indicate that even should Salmonella from imported Brazilian poultry products reach UK consumers, they are very unlikely to be causing disease. No evidence of the Brazilian strains of Salmonella Heidelberg or Salmonella Minnesota were observed in UK domestic chickens. These findings suggest that introduction of the Salmonella Enteritidis vaccine, in addition to increasing antimicrobial use, could have resulted in replacement of salmonellae in Brazilian poultry flocks with serovars that are more drug resistant, but less associated with disease in humans in the UK. The plasmids conferring resistance to beta-lactams, sulphonamides and tetracyclines likely conferred a competitive advantage to the Salmonella Minnesota and Salmonella Heidelberg serovars in this setting of high antimicrobial use, but the apparent lack of transfer to other serovars present in the same setting suggests barriers to horizontal gene transfer that could be exploited in intervention strategies to reduce AMR. The insights obtained reinforce the importance of One Health genomic surveillance.


Assuntos
Salmonella enterica , Animais , Antibacterianos/farmacologia , Brasil/epidemiologia , Galinhas , Farmacorresistência Bacteriana/genética , Aves Domésticas , Saúde Pública , Salmonella , Salmonella enterica/genética , Sulfonamidas , Tetraciclinas , beta-Lactamas
3.
Food Microbiol ; 106: 104043, 2022 Sep.
Artigo em Inglês | MEDLINE | ID: mdl-35690445

RESUMO

Biofilms are known to contribute to bacterial tolerance to desiccation and survival in low moisture foods. However, the molecular mechanisms underlying biofilm formation have not been fully elucidated. This study identified some of the genes that are implicated in biofilm formation by Salmonella enterica serovar Tennessee, the "peanut butter outbreak" strain. Mini-Tn10 mutagenesis was used in the study to generate random transposon insertion libraries. The ability of selected mutants in forming biofilms was compared with their wildtype parent using the crystal violet binding assay. Mutants forming significantly less (P ≤ 0.05) biofilm compared to their wildtype parent were selected for whole-genome sequencing. Mini-Tn10 insertion sites on mutant genomes were identified by comparing the acquired sequencing data with those in the Genbank using the BLAST search. In total, 56 mutants were obtained, and five were selected for further analysis according to the result of the biofilm assay. Sequencing analysis revealed that the mini-Tn10 interrupted the S. enterica genes that encode bacterial cell membrane lipoprotein, DNA topoisomerase III, attachment and invasion locus protein, bacteriocin immunity protein, and cell division protein. The information generated from the research should be useful in the control fo S. enterica in low-moisture foods and their production environments.


Assuntos
Salmonella enterica , Biofilmes , Mutagênese , Salmonella enterica/genética , Análise de Sequência de DNA , Sorogrupo , Tennessee
4.
Gut Microbes ; 14(1): 2089007, 2022.
Artigo em Inglês | MEDLINE | ID: mdl-35734810

RESUMO

Some serovars of Salmonella are not or rare found to cause salmonellosis in human. In our clinic-based surveillance, three rare Salmonella 4,5,12:a:- strains were recovered from three patients with diarrhea. To explore their genetic and epidemiological characteristics and pathogenesis, we conducted whole-genome sequencing, in vitro invasion assays in mammalian cells, and in vivo virulence assays in an animal model. The three isolates had indistinguishable molecular patterns and similar genome sequences, and clustered together with an isolate from edible fish traded among countries. The isolates had biochemical reactions identical with those of Salmonella subspecies enterica but belonged to subspecies salamae according to genome phylogeny, revealing a new serovar, S. enterica subsp. II serovar 4,5,12:a:-. The strains contained multiple virulence genes, elicited temporary bacteremia and enteritidis and caused cell damage in the mouse liver and cecum. This study provides evidence that this new Salmonella salamae serovar can infect humans and cause clusters of cases, and whole-genome sequencing detection and surveillance of Salmonella can help to accurately define Salmonella classification and clonality, improve diagnosis, facilitate outbreak detection and aid in the source tracing of salmonellosis epidemics.


Assuntos
Gastroenterite , Microbioma Gastrointestinal , Intoxicação Alimentar por Salmonella , Salmonelose Animal , Infecções por Salmonella , Salmonella enterica , Animais , Humanos , Mamíferos , Camundongos , Filogenia , Intoxicação Alimentar por Salmonella/epidemiologia , Salmonella enterica/genética , Sorogrupo
5.
Front Cell Infect Microbiol ; 12: 864087, 2022.
Artigo em Inglês | MEDLINE | ID: mdl-35755834

RESUMO

Thrombotic thrombocytopenic purpura (TTP) is one of the two classic thrombotic microangiopathy (TMA) diseases which could be induced by infections. To the best of our knowledge, this is the first report of an acquired immunodeficiency syndrome (AIDS) patient with acquired TTP induced by infection with Salmonella enterica serovar Typhimurium (hereafter, S. Typhimurium) isolate, S. Typhimurium_zhang, which was confirmed by serology and genetic taxonomy. The literature review identified 17 TMA-related genes encoding the candidate triggers, which were searched in the annotated genome sequence of S. Typhimurium_zhang. Anaerobic nitric oxide reductase flavorubredoxin (FlRd), encoded by norV which is related to another TMA, haemolytic uraemic syndrome (HUS), was found in S. Typhimurium_zhang. Basic local alignment search tool (BLAST) analysis revealed that norV and FlRd in S. Typhimurium_zhang, as well as eight S. Typhimurium type strains, have high identity with HUS-related Escherichia coli O157:H7 strain TW14359. Similar results were obtained from the BLAST analysis of 73 S. enterica isolates for congenital TTP which was also previously reported to be triggered by S. enterica. Phylogenetic analysis and amino acid sequence alignment revealed that FlRd was functional and highly conservative on 69 Enterobacteriaceae, including S. Typimurium_zhang and TW14359. In brief, we found norV in the genome of a S. Typhimurium clinical isolate that induced TTP in an AIDS patient. FlRd, the protein encoded by norV, probably triggered the TTP and was highly conservative, functional, and widespread in S. enterica and Enterobacteriaceae. More in vitro and in vivo studies are required to confirm our findings and determine the underlying mechanism.


Assuntos
Síndrome de Imunodeficiência Adquirida , Síndrome Hemolítico-Urêmica , Púrpura Trombocitopênica Trombótica , Salmonella enterica , Humanos , Filogenia , Púrpura Trombocitopênica Trombótica/diagnóstico , Salmonella enterica/genética , Salmonella typhimurium/genética , Sorogrupo
6.
Vet Res ; 53(1): 46, 2022 Jun 22.
Artigo em Inglês | MEDLINE | ID: mdl-35733156

RESUMO

A universal vaccine protecting against multiple serotypes of Streptococcus suis is urgently needed to improve animal welfare and reduce the consumption of antibiotics. In this study, a dual antigen expression cassette consisting of SS2-SaoA and SS9-Eno was delivered by a recombinant Salmonella Choleraesuis vector to form the vaccine candidate rSC0016(pS-SE). SaoA and Eno were simultaneously synthesized in rSC0016(pS-SE) without affecting the colonization of the recombinant vector in the lymphatic system. In addition, the antiserum of mice immunized with rSC0016(pS-SE) produced a broader and potent opsonophagocytic response against multiple serotypes of S. suis. Finally, rSC0016(pS-SE) provided mice with a 100% protection against a lethal dose of parent S. suis serotype 2 and serotype 9, and provided 90% and 80% protection against heterologous S. suis serotype 7 or 1/2. These values were significantly higher than those obtained with rSC0016(pS-SaoA) or rSC0016(pS-Eno). Together, this study serves as a foundation for developing a universal vaccine against multiple serotypes of S. suis.


Assuntos
Vacinas Bacterianas , Proteção Cruzada , Salmonella enterica , Infecções Estreptocócicas , Streptococcus suis , Animais , Vacinas Bacterianas/imunologia , Proteção Cruzada/imunologia , Modelos Animais de Doenças , Camundongos , Salmonella enterica/genética , Salmonella enterica/imunologia , Sorogrupo , Infecções Estreptocócicas/prevenção & controle , Infecções Estreptocócicas/veterinária , Streptococcus suis/genética , Streptococcus suis/imunologia
7.
Food Res Int ; 157: 111393, 2022 Jul.
Artigo em Inglês | MEDLINE | ID: mdl-35761648

RESUMO

Fine ground black pepper generally consumed as a seasoning without any further processing has been associated with Salmonella enterica outbreaks. Thermal inactivation kinetics data is necessary to develop a pasteurization process for fine ground black pepper. This study investigates the influence of temperature and water activity on thermal inactivation kinetics of Salmonella in fine ground black pepper. It also assesses the suitability of Enterococcus faecium as a surrogate for Salmonella. Fine ground black pepper of varying water activities, aw (0.40, 0.55, 0.70) was subjected to isothermal treatments at different temperatures (65-80 °C) for five equidistant time points with intervals ranging from 18 s to 250 min. The survival data were used to fit two primary models (log-linear and Weibull) and two secondary models (response surface and Modified Bigelow). Results indicated that among the two primary models, the Weibull model explained the thermal inactivation kinetics better with lower RMSE (0.24 - 0.56 log CFU/g) and AICc values at all aw and temperatures. Water activity and treatment temperature significantly enhanced the thermal inactivation of Salmonella. E. faecium NRRL B-2354 was found to be a suitable surrogate for Salmonella in fine ground black pepper at all tested treatment conditions. The developed modified Bigelow model based on the Weibull model could be applied to predict the inactivation kinetics of Salmonella in black pepper and would benefit the spice industry in identifying process parameters for thermal pasteurization of fine ground black pepper.


Assuntos
Enterococcus faecium , Piper nigrum , Salmonella enterica , Contagem de Colônia Microbiana , Enterococcus faecium/fisiologia , Microbiologia de Alimentos , Temperatura Alta , Cinética , Salmonella/fisiologia , Temperatura , Água/análise
8.
Emerg Infect Dis ; 28(7): 1410-1420, 2022 07.
Artigo em Inglês | MEDLINE | ID: mdl-35731173

RESUMO

Extended-spectrum ß-lactamases (ESBLs) confer resistance to extended-spectrum cephalosporins, a major class of clinical antimicrobial drugs. We used genomic analysis to investigate whether domestic food animals, retail meat, and pets were reservoirs of ESBL-producing Salmonella for human infection in Canada. Of 30,303 Salmonella isolates tested during 2012-2016, we detected 95 ESBL producers. ESBL serotypes and alleles were mostly different between humans (n = 54) and animals/meat (n = 41). Two exceptions were blaSHV-2 and blaCTX-M-1 IncI1 plasmids, which were found in both sources. A subclade of S. enterica serovar Heidelberg isolates carrying the same IncI1-blaSHV-2 plasmid differed by only 1-7 single nucleotide variants. The most common ESBL producer in humans was Salmonella Infantis carrying blaCTX-M-65, which has since emerged in poultry in other countries. There were few instances of similar isolates and plasmids, suggesting that domestic animals and retail meat might have been minor reservoirs of ESBL-producing Salmonella for human infection.


Assuntos
Saúde Única , Salmonella enterica , Animais , Antibacterianos/farmacologia , Galinhas , Genômica , Plasmídeos/genética , Salmonella , beta-Lactamases/genética
9.
BMC Infect Dis ; 22(1): 557, 2022 Jun 18.
Artigo em Inglês | MEDLINE | ID: mdl-35717143

RESUMO

BACKGROUND: Splenic cyst complicated by non-typhoid Salmonella infection is rare in healthy individuals in the era of antibiotics. Salmonella enterica subsp. enterica serovar Livingstone causing infection of giant splenic cyst has not been previously reported. CASE PRESENTATION: We report a case of giant splenic cyst (maximum diameter, 21 cm) complicated with Salmonella Livingstone infection, which resulted in splenic abscess, in a 16-year-old previously healthy adolescent male. The splenic abscess was successfully treated with ultrasonography-guided percutaneous drainage and antimicrobial therapy. CONCLUSION: Infection of splenic cyst may be caused by S. Livingstone in immunocompetent individuals. This case may help clinicians to raise awareness towards splenic abscess and highlights the importance of drainage and antimicrobial agents to avoid splenectomy.


Assuntos
Abscesso Abdominal , Cistos , Infecções Intra-Abdominais , Infecções por Salmonella , Salmonella enterica , Esplenopatias , Abscesso Abdominal/tratamento farmacológico , Abscesso/tratamento farmacológico , Adolescente , Antibacterianos/uso terapêutico , Drenagem/métodos , Humanos , Infecções Intra-Abdominais/tratamento farmacológico , Masculino , Salmonella , Infecções por Salmonella/complicações , Infecções por Salmonella/diagnóstico , Infecções por Salmonella/tratamento farmacológico , Sorogrupo , Esplenopatias/complicações , Esplenopatias/diagnóstico , Esplenopatias/cirurgia
10.
Microbiol Spectr ; 10(3): e0220221, 2022 Jun 29.
Artigo em Inglês | MEDLINE | ID: mdl-35532355

RESUMO

Salmonella enterica serovar I 4,[5],12:i:- is a foodborne pathogen of concern because many isolates are multidrug-resistant (resistant to ≥3 antimicrobial classes) and metal tolerant. In this study, three in-feed additives were individually tested for their ability to reduce Salmonella I 4,[5],12:i:- shedding in swine: resistant potato starch (RPS), high amylose corn starch, and a fatty acid blend, compared with a standard control diet over 21 days. Only RPS-fed pigs exhibited a reduction in Salmonella fecal shedding, different bacterial community compositions, and different cecal short chain fatty acid (SCFA) profiles relative to control animals. Within the RPS treatment group, pigs shedding the least Salmonella tended to have greater cecal concentrations of butyrate, valerate, caproate, and succinate. Additionally, among RPS-fed pigs, several bacterial taxa (Prevotella_7, Olsenella, and Bifidobacterium, and others) exhibited negative relationships between their abundances of and the amount of Salmonella in the feces of their hosts. Many of these same taxa also had significant positive associations with cecal concentrations of butyrate, valerate, caproate, even though they are not known to produce these SCFAs. Together, these data suggest the RPS-associated reduction in Salmonella shedding may be dependent on the establishment of bacterial cross feeding interactions that result in the production of certain SCFAs. However, directly feeding a fatty acid mix did not replicate the effect. RPS supplementation could be an effective means to reduce multidrug-resistant (MDR) S. enterica serovar I 4,[5],12:i:- in swine, provided appropriate bacterial communities are present in the gut. IMPORTANCE Prebiotics, such as resistant potato starch (RPS), are types of food that help to support beneficial bacteria and their activities in the intestines. Salmonella enterica serovar I 4,[5],12:i:- is a foodborne pathogen that commonly resides in the intestines of pigs without disease, but can make humans sick if unintentionally consumed. Here we show that in Salmonella inoculated pigs, feeding them a diet containing RPS altered the colonization and activity of certain beneficial bacteria in a way that reduced the amount of Salmonella in their feces. Additionally, within those fed RPS, swine with higher abundance of these types of beneficial bacteria had less Salmonella I 4,[5],12:i:- in their feces. This work illustrates likely synergy between the prebiotic RPS and the presence of certain gut microorganisms to reduce the amount of Salmonella in the feces of pigs and therefore reduce the risk that humans will become ill with MDR Salmonella serovar I 4,[5],12:i:-.


Assuntos
Salmonelose Animal , Salmonella enterica , Solanum tuberosum , Doenças dos Suínos , Animais , Butiratos , Caproatos , Dieta/veterinária , Suplementos Nutricionais , Ácidos Graxos Voláteis , Fezes/microbiologia , Prebióticos , Amido Resistente , Salmonella , Salmonelose Animal/microbiologia , Salmonelose Animal/prevenção & controle , Sorogrupo , Amido , Suínos , Doenças dos Suínos/microbiologia , Valeratos
11.
J Food Prot ; 85(7): 1008-1016, 2022 Jul 01.
Artigo em Inglês | MEDLINE | ID: mdl-35499403

RESUMO

ABSTRACT: Pork head meat may harbor Salmonella and contaminate other carcass by-products during harvest and fabrication. A large pork processing plant in the United States was sampled bimonthly for 11 months to determine the concentration, prevalence, seasonality, serotype diversity, and antimicrobial susceptibility of Salmonella enterica isolated from cheek meat and head trim of swine carcasses. Each collection consisted of 25 samples on two consecutive days in the morning and afternoon shifts, for a total of 100 cheek meat and 100 head trim samples each month. Tissues were cultured for Salmonella by using restrictive media and enrichment techniques, and a subset of isolates was serotyped, analyzed for antimicrobial susceptibility, and genome sequenced. Salmonella postenrichment prevalence did not differ (P = 0.20) between cheek meat (63%) and head trim (66%). Postenrichment prevalence differed (P < 0.05) by month (January, 94%; March, 80%; May, 54%; July, 59%; September, 47%; and November, 55%) and by processing shift (morning, 68%; afternoon, 62%). The subset (n = 618) of isolates selected for serotyping yielded 21 distinct serotypes: Typhimurium (49%), Infantis (10%), Heidelberg (8%), I 4,[5],12:i:- (8%), and 17 other types (≤5%). In total, 407 multidrug-resistant (MDR; resistance to three or more antibiotic classes) isolates were identified. There were 120 isolates that exhibited the penta-resistant ACSSuT phenotype. In addition, 113 isolates exhibited decreased susceptibility to ciprofloxacin (MIC ≥ 0.12 µg/mL). Resistance genes blaCARB, blaSHV, blaTEM, aac(6')-Ib-cr,qnrB, sul2, and dfrA were expressed in numerous MDR Salmonella isolates. The data herein suggest that pork products from the head, compared with data reported for carcasses, may have a relatively high prevalence of Salmonella with diverse serotypes and MDR.


Assuntos
Carne de Porco , Carne Vermelha , Salmonella enterica , Animais , Antibacterianos/farmacologia , Farmacorresistência Bacteriana , Farmacorresistência Bacteriana Múltipla , Carne , Testes de Sensibilidade Microbiana , Prevalência , Salmonella , Sorotipagem , Suínos , Estados Unidos
12.
Epidemiol Infect ; 150: e110, 2022 May 10.
Artigo em Inglês | MEDLINE | ID: mdl-35535461

RESUMO

This study aimed to determine the epidemiology and association of antimicrobial resistance (AMR) among Escherichia coli and Salmonella in Thailand. The E. coli (n = 1047) and Salmonella (n = 816) isolates from pigs, pork and humans were screened for 18 replicons including HI1, HI2, I1-γ, X, L/M, N, FIA, FIB, W, Y, P, FIC, A/C, T, FIIAs, F, K and B/O using polymerase chain reaction-based replicon typing. The E. coli (n = 26) and Salmonella (n = 3) isolates carrying IncF family replicons, ESBL and/or mcr genes were determined for FAB formula. IncF represented the major type of plasmids. Sixteen and eleven Inc groups were identified in E. coli (85.3%) and Salmonella (25.7%), respectively. The predominant replicon patterns between E. coli and Salmonella were IncK-F (23.7%) and IncF (46.2%). Significant correlations (P < 0.05) were observed between plasmid-replicon type and resistance phenotype. Plasmid replicon types were significantly different among sources of isolates and sampling periods. The most common FAB types between E. coli and Salmonella were F2:A-:B- (30.8%) and S1:A-:B- (66.7%), respectively. In conclusion, various plasmids present in E. coli and Salmonella. Responsible and prudent use of antimicrobials is suggested to reduce the selective pressures that favour the spread of AMR determinants. Further studies to understand the evolution of R plasmids and their contribution to the dissemination of AMR genes are warranted.


Assuntos
Infecções por Escherichia coli , Carne de Porco , Carne Vermelha , Salmonella enterica , Animais , Antibacterianos/farmacologia , Escherichia coli/genética , Infecções por Escherichia coli/epidemiologia , Infecções por Escherichia coli/veterinária , Humanos , Plasmídeos/genética , Salmonella/genética , Salmonella enterica/genética , Suínos , beta-Lactamases/genética
13.
Methods Mol Biol ; 2427: 167-175, 2022.
Artigo em Inglês | MEDLINE | ID: mdl-35619033

RESUMO

Human infections by gastrointestinal bacterial pathogens are commonly associated with the consumption of contaminated food of animal origin (e.g., chicken, fish, eggs) or contaminated water. However, further contamination sources must be considered since number of Salmonella enterica infections associated with the consumption of food of non-animal origin (e.g., vegetables, fruits, nuts) are increasing. This gives raise to interest in understanding the interaction of S. enterica with leafy produce, such as various salads. Especially adhesion as initial step of contamination of salad by S. enterica deserves further investigation. Here we introduce methods to analyse Salmonella adhesion to various salads that provide insights into bacterial factors involved in Salmonella colonization of plants.


Assuntos
Contaminação de Alimentos , Alface , Folhas de Planta , Salmonella enterica , Alface/microbiologia , Folhas de Planta/microbiologia
14.
J Microbiol Methods ; 198: 106496, 2022 Jul.
Artigo em Inglês | MEDLINE | ID: mdl-35636574

RESUMO

A method for testing the antibiotic susceptibility of foodborne bacterial samples using a portable Raman spectrometer has been developed. Surface-enhanced Raman spectroscopy (SERS) was used to obtain the spectra from bacterial samples collected on a filter membrane after incubation with antibiotics. The SERS spectra revealed characteristic antibiotic response patterns, which can be used to assess the antibiotic sensitivity of the samples. Several species of bacteria, including Escherichia coli, Bacillus cereus, and Salmonella enterica, were used to test the procedure, as well as multiple classes of antibiotics. Characteristic bacterial SERS peaks could be identified in the spectra, as well as clear antibiotic response patterns that were consistent across the different species of bacteria and could be used to reliably determine the antibiotic sensitivity of the samples. The portable SERS method was then used to test bacteria isolated from ground beef, and the results show the procedure could be used to accurately test the antibiotic sensitivity of bacteria isolated from real food samples. Further optimization of this method to test the filtered liquid obtained from bacterial samples has demonstrated the capability of a simpler approach to identify antibiotic response patterns. The effectiveness and improved accessibility of the portable SERS method indicates that these procedures have great potential for future use in low-resource settings, which will facilitate the monitoring and control of antibiotic resistance.


Assuntos
Antibacterianos , Salmonella enterica , Animais , Antibacterianos/farmacologia , Bovinos , Escherichia coli , Análise Espectral Raman/métodos
15.
Open Vet J ; 12(2): 303-307, 2022.
Artigo em Inglês | MEDLINE | ID: mdl-35603068

RESUMO

Background: In Italy, an autogenous registered vaccine, adjuvanted with aluminum hydroxide, can be administrated to contrast Salmonella enterica subsp. enterica serovar abortus equi infection, coupled to a specific antimicrobial treatment. Case Description: Here, we report the case of an abortion outbreak by Salmonella abortus equi in Central Italy where mares were vaccinated but immediately developed a strong local reaction, maybe due to the adjuvant. Promptly, another autogenous vaccine, substituting the aluminum hydroxide with a new generation adjuvant (Montanide™ Seppic IMS1313), was produced and administrated. The new formulated vaccine did not cause any adverse outcome and conferred high protection titers against the infection. To the best of our knowledge, this is the first reported case of immunization by a vaccine adjuvanted with Montanide™ Seppic IMS1313 in horses. Conclusion: This approach may be used as a preventive strategy for further outbreaks in association with the application of recommended biosafety principles.


Assuntos
Autovacinas , Salmonella enterica , Adjuvantes Imunológicos , Adjuvantes Farmacêuticos , Hidróxido de Alumínio , Animais , Surtos de Doenças/prevenção & controle , Surtos de Doenças/veterinária , Feminino , Cavalos , Gravidez , Salmonella , Sorogrupo
16.
PLoS Negl Trop Dis ; 16(5): e0010414, 2022 05.
Artigo em Inglês | MEDLINE | ID: mdl-35613181

RESUMO

Community-acquired bacterial bloodstream infections are caused by diverse pathogens with changing antimicrobial-resistance patterns. In low-middle income countries in Southeast Asia, where dengue fever is endemic and a leading cause of fever, limited information is available about bacterial bloodstream infections due to challenges of implementing a blood culture service. This study describes bacterial bloodstream pathogens and antimicrobial-resistance patterns in Metro Manila, the Philippines. We aimed to identify the proportion of patients with a positive blood culture, the bacteria isolated and their antimicrobial resistance patterns, and the clinical characteristics of these patients, in this dengue endemic area. We conducted a prospective observational study in a single hospital enrolling febrile patients clinically suspected of having a community-acquired bacterial bloodstream infection between 1st July 2015 and 30th June 2019. Each patient had a blood culture and additional diagnostic tests according to their clinical presentation. We enrolled 1315 patients and a significant positive blood culture was found in 77 (5.9%) including Staphylococcus aureus (n = 20), Salmonella enterica Typhi (n = 18), Escherichia coli (n = 16), Streptococcus pneumoniae (n = 3) and Burkholderia pseudomallei (n = 2). Thirty-four patients had meningococcal disease diagnosed by culture (n = 8) or blood PCR (n = 26). Additional confirmed diagnoses included leptospirosis (n = 177), dengue virus infection (n = 159) and respiratory diphtheria (n = 50). There were 79 (6.0%, 95%CI 4.8%-7.4%) patients who died within 28 days of enrollment. Patients with a positive blood culture were significantly more likely to die than patients with negative culture (15.2% vs 4.4%, P<0.01). Among S. aureus isolates, 11/20 (55%) were methicillin-resistant (MRSA) and ST30: USA1100 was dominant sequence type (88.9%). Antimicrobial-susceptibility was well preserved in S. enterica Typhi. Among hospitalized patients with clinically suspected community-acquired bacterial bloodstream infection in Metro Manila, the Philippines, 5.9% had a blood culture confirmed infection of whom 15.6% died. S. aureus, including a significant number of MRSA (USA1100 clones), S. enterica Typhi, E.coli and Neisseria meningitidis were frequently identified pathogens.


Assuntos
Bacteriemia , Infecções Comunitárias Adquiridas , Dengue , Salmonella enterica , Sepse , Infecções Estafilocócicas , Antibacterianos/uso terapêutico , Bacteriemia/microbiologia , Infecções Comunitárias Adquiridas/tratamento farmacológico , Dengue/complicações , Farmacorresistência Bacteriana , Escherichia coli , Febre/epidemiologia , Humanos , Testes de Sensibilidade Microbiana , Filipinas/epidemiologia , Salmonella typhi , Sepse/microbiologia , Staphylococcus aureus
17.
Sci Rep ; 12(1): 7313, 2022 05 04.
Artigo em Inglês | MEDLINE | ID: mdl-35508535

RESUMO

Salmonella enterica is ubiquitous in the plant environment, persisting in the face of UV stress, plant defense responses, desiccation, and nutrient limitation. These fluctuating conditions of the leaf surface result in S. enterica population decline. Biomultipliers, such as the phytopathogenic bacterium Xanthomonas hortorum pv. gardneri (Xhg), alter the phyllosphere to the benefit of S. enterica. Specific Xhg-dependent changes to this niche that promote S. enterica persistence remain unclear, and this work focuses on identifying factors that lead to increased S. enterica survival on leaves. Here, we show that the Xhg transcription activator-like effector AvrHah1 is both necessary and sufficient for increased survival of S. enterica on tomato leaves. An Xhg avrHah1 mutant fails to influence S. enterica survival while addition of avrHah1 to X. vesicatoria provides a gain of function. Our results indicate that although Xhg stimulates a robust immune response from the plant, AvrHah1 is not required for these effects. In addition, we demonstrate that cellular leakage that occurs during disease is independent of AvrHah1. Investigation of the interaction between S. enterica, Xhg, and the plant host provides information regarding how an inhospitable environment changes during infection and can be transformed into a habitable niche.


Assuntos
Lycopersicon esculentum , Salmonella enterica , Xanthomonas , Animais , Lycopersicon esculentum/microbiologia , Doenças das Plantas/microbiologia , Folhas de Planta/microbiologia , Salmonella enterica/genética , Efetores Semelhantes a Ativadores de Transcrição , Xanthomonas/genética
18.
Microbiol Res ; 261: 127052, 2022 Aug.
Artigo em Inglês | MEDLINE | ID: mdl-35533436

RESUMO

In light of spreading antibiotic resistance among pathogenic bacteria, the development of novel approaches to combat such microorganisms is crucial. Salmonella enterica is pathogenic to humans, however, it can also infect poultry, being a potential foodborne pathogen when poultry-derived food is contaminated by this bacterium. Phage therapy is one of the alternative ways to treat Salmonella-infected animals while the establishment of this method and its introduction to a general practice requires detailed studies on safety and efficacy. Here, we present the results of such studies with two previously isolated and characterized bacteriophages, vB_SenM2 and vB_Sen-TO17, and four strains of S. enterica belonging to two serovars, Typhimurium and Enteritidis. We demonstrated effective reduction of bacterial cell number and cell culture density when using each phage alone, and in combination (as a cocktail). These phages were also effective in reducing bacterial biofilm. The efficacy of this in vitro phage therapy was compared to the action of known antibiotics, as was the efficiency of appearance of bacteria resistant to both these types of antibacterial agents. Safety of the use of bacteriophages was demonstrated using the LAL chromogenic test and the chicken fibroblast viability assay. Finally, the efficacy of phage therapy was assessed with the in vivo model of S. enterica-infected Galleria mellonella larvae, showing a significant improvement in the survival of the animals. In conclusion, we demonstrated high efficacy and acceptable safety profiles of phage therapy against S. enterica strains using vB_SenM-2 and vB_Sen-TO17 phages (both alone and in a cocktail). These results open a possibility for a trial with the use of poultry and these phages which might potentially allow to introduce of this method for practical use in poultry farming.


Assuntos
Bacteriófagos , Terapia por Fagos , Fagos de Salmonella , Salmonella enterica , Animais , Modelos Animais de Doenças , Técnicas In Vitro , Aves Domésticas , Salmonella enteritidis , Salmonella typhimurium , Sorogrupo
19.
J Food Prot ; 85(7): 1044-1052, 2022 Jul 01.
Artigo em Inglês | MEDLINE | ID: mdl-35512125

RESUMO

ABSTRACT: Tomatoes (Solanum lycopersicum) are one of the most commonly consumed fruits worldwide. The fruit can become contaminated with Salmonella and Listeria monocytogenes at various stages of the production and supply chain, and these pathogens may survive under various storage conditions. The effects of relative humidity, temperature, and duration of storage on the attachment and survival of both pathogens on the surface of tomatoes were investigated. Fresh whole Roma tomatoes were inoculated with a cocktail of Salmonella or L. monocytogenes strains and stored at 5, 12, 25, 30, or 35°C for up to 10 days. Every day during storage, relative humidity and temperature were measured and tomatoes were removed to enumerate pathogens cells that were loosely attached (LA; cells were detached from the tomato surface by rinsing) and strongly attached (SA; sonication was required to detach cells from the tomato surface). The attachment strength (SR) was calculated to express the proportion of surviving SA cells on the tomato surface. The initial levels of Salmonella and L. monocytogenes on the tomato surface after inoculation were 6.6 and 6.5 log CFU per tomato for LA cells and 5.1 and 5.6 log CFU per tomato for SA cells, respectively. For both pathogens, the LA levels were higher (P < 0.05) than the SA levels. The LA and SA levels differed significantly as a function of temperature, relative humidity, and duration of storage. The SR for Salmonella was affected by storage time but not temperature, whereas the SR for L. monocytogenes was affected by storage time and temperature and relative humidity (P < 0.05). An understanding of the attachment and survival of Salmonella and L. monocytogenes on tomatoes stored under various temperature conditions may be useful for preventing or reducing the establishment of pathogens and for designing improved decontamination methods.


Assuntos
Listeria monocytogenes , Lycopersicon esculentum , Salmonella enterica , Contagem de Colônia Microbiana , Microbiologia de Alimentos , Umidade , Salmonella , Temperatura
20.
PLoS One ; 17(5): e0266443, 2022.
Artigo em Inglês | MEDLINE | ID: mdl-35588421

RESUMO

Salmonella enterica serovar 4,[5],12:i:-, a monophasic variant of Salmonella Typhimurium lacking the phase 2 flagellin, is one of the common serotypes causing Salmonellosis worldwide. However, information on Salmonella serovar 4,[5],12:i:- from Guizhou Province has lacked so far. This study aimed to investigate the antimicrobial resistance, the presence of antimicrobial resistance genes and virulence genes, and characterize the MLST genotypes of Salmonella serovar 4,[5],12:i:- isolates from Guizhou province, China. We collected 363 non-typhoid Salmonella (NTS) isolates of Guizhou from 2013 to 2018. Biochemical identification, serogroups testing, and specific multiplex polymerase chain reaction (mPCR) assay were conducted to identify Salmonella 4,[5],12:i:- isolates. Isolates were determined the antimicrobial resistance by the micro broth dilution method, detected the presence of antimicrobial resistance genes and virulence genes by PCR, and examined the molecular genotyping by Multilocus sequence typing (MLST). Eighty-seven Salmonella 4,[5],12:i:- isolates were detected, accounting for 23.9% (87/363) of the total NTS isolates. All Salmonella 4,[5],12:i:- isolates showed highly resistant to sulfaoxazole (93.1%), streptomycin (90.8%), ampicillin (88.5%), tetracycline (86.2%) and doxycycline (86.2%). A high proportion (94.2%) of multi-drug resistance (MDR) isolates were found. Most (83.9%) Salmonella 4,[5],12:i:- isolates carried four antimicrobial resistance genes, especially blaTEM-1, strA-strB, sul2, and tetB genes. Salmonella 4,[5],12:i:- isolates showed a high rate of invA, sseL, mgtC, siiE, sopB, gipA, gtgB, sspH1, and sspH2 (72.4%~98.9%). On the contrary, none of the isolates were detected the spvC and pefA genes. MLST analysis revealed three sequence types (STs), and ST34 (97.7%) was the dominant sequence type. This study is the first report of Salmonella 4,[5],12:i:- in humans from Guizhou province, China. The data might be useful for rational antimicrobial usage against Salmonella 4,[5],12:i:- infections, risk management, and public health strategies in Guizhou.


Assuntos
Anti-Infecciosos , Salmonella enterica , Antibacterianos/farmacologia , Farmacorresistência Bacteriana/genética , Resistência a Múltiplos Medicamentos , Farmacorresistência Bacteriana Múltipla/genética , Humanos , Testes de Sensibilidade Microbiana , Tipagem de Sequências Multilocus , Salmonella enterica/genética , Salmonella typhimurium , Sorogrupo , Virulência/genética
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