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Sample records for acid auxotrophic salmonella

  1. An engineered bacterium auxotrophic for an unnatural amino acid: a novel biological containment system

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    Yusuke Kato

    2015-09-01

    Full Text Available Biological containment is a genetic technique that programs dangerous organisms to grow only in the laboratory and to die in the natural environment. Auxotrophy for a substance not found in the natural environment is an ideal biological containment. Here, we constructed an Escherichia coli strain that cannot survive in the absence of the unnatural amino acid 3-iodo-L-tyrosine. This synthetic auxotrophy was achieved by conditional production of the antidote protein against the highly toxic enzyme colicin E3. An amber stop codon was inserted in the antidote gene. The translation of the antidote mRNA was controlled by a translational switch using amber-specific 3-iodo-L-tyrosine incorporation. The antidote is synthesized only when 3-iodo-L-tyrosine is present in the culture medium. The viability of this strain rapidly decreased with less than a 1 h half-life after removal of 3-iodo-L-tyrosine, suggesting that the decay of the antidote causes the host killing by activated colicin E3 in the absence of this unnatural amino acid. The contained strain grew 1.5 times more slowly than the parent strains. The escaper frequency was estimated to be 1.4 mutations (95% highest posterior density 1.1–1.8 per 105 cell divisions. This containment system can be constructed by only plasmid introduction without genome editing, suggesting that this system may be applicable to other microbes carrying toxin-antidote systems similar to that of colicin E3.

  2. Sterol-mediated regulation of mevalonic acid synthesis. Accumulation of 4-carboxysterols as the predominant sterols synthesized in a Chinese hamster ovary cell cholesterol auxotroph (mutant 215)

    International Nuclear Information System (INIS)

    Plemenitas, A.; Havel, C.M.; Watson, J.A.

    1990-01-01

    Chinese hamster ovary-215 (CHO-215) mutant cells are auxotrophic for cholesterol. Berry and Chang (Berry, D. J., and Chang, T. Y. (1982) Biochemistry 21, 573-580) suggested that the metabolic lesion was at the level of 4-methyl sterol oxidation. However, the observed cellular accumulation of lanosterol was not consistent with a defect at this metabolic site. With the use of a novel Silica Sep Pak sterol separation procedure, we demonstrated that 60-80% of the acetonesoluble lipid radioactivity in [5-3H]mevalonate-labeled CHO-215 cells was incorporated into acidic sterols. 7(8),Cholesten-4 beta-methyl,4 alpha-carboxy,3 beta-ol was the dominant end product. In addition to this acidic sterol, 7(8),24-cholestadien,4 beta-methyl,4 alpha-carboxy,3 beta-ol and 7(8),24-cholestadien,4 alpha-carboxy,3 beta-ol were also isolated. Incubation of cell-free extracts with [3H]7(8)-cholesten-4 beta-methyl, 4 alpha-carboxy,3 beta-ol and pyridine nucleotides confirmed that CHO-215 4-carboxysterol decarboxylase activity was less than 1% of that for wild type cells. Thus, a correspondence between decreased 4-carboxysterol decarboxylase activity and the spectrum of accumulated sterol products by intact CHO-215 cells was demonstrated. No detectable cholesterol was synthesized by CHO-215 cells. 3H-Product accumulation studies demonstrated that 7(8),24-cholestadien, 4 beta-methyl,4 alpha-carboxy,3 beta-ol increased prior to its subsequent saturation at the delta 24 carbon. Furthermore, the steady state ratio for delta 24-saturated acidic sterols/unsaturated acidic sterols was dependent on media cholesterol source and amount. Finally, the accumulated acidic sterol(s) were not regulatory signal molecules for the modulation of 3-hydroxy-3-methyl-glutaryl coenzyme. A reductase activity in response to cholesterol availability

  3. Salmonella

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    ... Compartir Find out about Salmonella infections linked to Kellogg’s Honey Smacks Cereal Find out about Salmonella infections ... Outbreaks Multistate Outbreak of Salmonella Infections Linked to Kellogg’s Honey Smacks Cereal Multistate Outbreak of Salmonella Adelaide ...

  4. Arginine-dependent acid resistance in Salmonella enterica serovar Typhimurium

    NARCIS (Netherlands)

    Kieboom, J.; Abee, T.

    2006-01-01

    Salmonella enterica serovar Typhimurium does not survive a pH 2.5 acid challenge under conditions similar to those used for Escherichia coli (J. W. Foster, Nat. Rev. Microbiol. 2:898-907, 2004). Here, we provide evidence that S. enterica serovar Typhimurium can display arginine-dependent acid

  5. Amoxicillin / Clavulanic Acid and Cefotaxime Resistance in Salmonella Minnesota and Salmonella Heidelberg from Broiler Chickens

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    Rodrigues IBBE

    2017-10-01

    Full Text Available This study investigated the resistance of various Salmonella strains to beta-lactam antibiotics. Salmonella Minnesota (36 strains and Salmonella Heidelberg (24 strains were isolated from broiler chickens and carcasses by the Disk Diffusion Test and resistance genes blaCTX-M-8, blaACC-1 and blaCMY-2 were detected by PCR. Of the 60 strains tested, 80% were resistant to at least one antibiotic. Specifically, 66.7% were resistant to amoxicillin/clavulanic acid and 75% were resistant to cefotaxime. Among the amoxicillin/clavulanic acid resistant strains, the blaCMY-2 gene was detected in 40%, blaACC-1 in 37.5% and blaCTX-M-8 in 7.5%. Among the cefotaxime resistant strains, we detected the genes blaCTX-M-8 in 13.3%, blaACC-1 in 33.3%, and blaCMY-2 in 31.1%. The presence of cefotaxime- and amoxicillin/clavulanic acid-resistant Salmonella in poultry, and the prevalence of extended spectrum betalactamases and AmpC-betalactamases in these strains are of huge concern to public health and economy.

  6. Organic acids for control of Salmonella in different feed materials

    DEFF Research Database (Denmark)

    Koyuncu, Sevinc; Andersson, Mats Gunnar; Löfström, Charlotta

    2013-01-01

    of FA, propionic acid (PA) and sodium formate (SF) was investigated. Four Salmonella strains isolated from feed were assayed for their acid tolerance. Also, the effect of lower temperatures (5°C and 15°C) compared to room temperature was investigated in rape seed and soybean meal. Results The efficacy...... of acid treatments varied significantly between different feed materials. The strongest reduction was seen in pelleted and compound mash feed (2.5 log10 reduction) followed by rapeseed meal (1 log10 reduction) after 5 days exposure. However, in soybean meal the acid effects were limited (less than 0.5 log......10 reduction) even after several weeks’ exposure. In all experiments the survival curves showed a concave shape, with a fast initial death phase followed by reduction at a slower rate during the remaining time of the experiment. No difference in Salmonella reduction was observed between FA...

  7. Efficacy of Lactic Acid, Lactic Acid-Acetic Acid Blends, and Peracetic Acid To Reduce Salmonella on Chicken Parts under Simulated Commercial Processing Conditions.

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    Ramirex-Hernandez, Alejandra; Brashears, Mindy M; Sanchez-Plata, Marcos X

    2018-01-01

    The poultry processing industry has been undergoing a series of changes as it modifies processing practices to comply with new performance standards for chicken parts and comminuted poultry products. The regulatory approach encourages the use of intervention strategies to prevent and control foodborne pathogens in poultry products and thus improve food safety and protect human health. The present studies were conducted to evaluate the efficacy of antimicrobial interventions for reducing Salmonella on inoculated chicken parts under simulated commercial processing conditions. Chicken pieces were inoculated by immersion in a five-strain Salmonella cocktail at 6 log CFU/mL and then treated with organic acids and oxidizing agents on a commercial rinsing conveyor belt. The efficacy of spraying with six different treatments (sterile water, lactic acid, acetic acid, buffered lactic acid, acetic acid in combination with lactic acid, and peracetic acid) at two concentrations was evaluated on skin-on and skin-off chicken thighs at three application temperatures. Skinless chicken breasts were used to evaluate the antimicrobial efficacy of lactic acid and peracetic acid. The color stability of treated and untreated chicken parts was assessed after the acid interventions. The lactic acid and buffered lactic acid treatments produced the greatest reductions in Salmonella counts. Significant differences between the control and water treatments were identified for 5.11% lactic acid and 5.85% buffered lactic acid in both skin-on and skin-off chicken thighs. No significant effect of treatment temperature for skin-on chicken thighs was found. Lactic acid and peracetic acid were effective agents for eluting Salmonella cells attached to chicken breasts.

  8. Impact of desiccation and heat exposure stress on Salmonella tolerance to acidic conditions.

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    Richardson, Kurt E; Cox, Nelson A; Cosby, Douglas E; Berrang, Mark E

    2018-02-01

    In a recent study, the pH of commonly used Salmonella pre-enrichment media became acidic (pH 4.0 to 5.0) when feed or feed ingredients were incubated for 24 h. Acidic conditions have been reported to injure or kill Salmonella. In this study, cultures of four known feed isolates (S. montevideo, S. senftenberg, S. tennessee, and S. schwarzengrund) and four important processing plant isolates (S. typhimurium, S. enteritidis, S. infantis, and S. heidelberg) were grown on meat and bone meal and later subjected to desiccation and heat exposure to stress the microorganism. The impact of stress on the isolates ability to survive in acidic conditions ranging from pH 4.0 to 7.0 was compared to the non-stressed isolate. Cell injury was determined on xylose lysine tergitol 4 (XLT4) and cell death determined on nutrient agar (NA). When measured by cell death in non-stressed Salmonella, S. typhimurium was the most acid tolerant and S. heidelberg was the most acid sensitive whereas in stressed Salmonella, S. senftenberg was the most acid tolerant and S. tennessee was the most acid sensitive. The pH required to cause cell injury varied among isolates. With some isolates, the pH required for 50% cell death and 50% cell injury was similar. In other isolates, cell injury occurred at a more neutral pH. These findings suggest that the pH of pre-enrichment media may influence the recovery and bias the serotype of Salmonella recovered from feed during pre-enrichment.

  9. Efficiency of organic acid preparations for the elimination of naturally occurring Salmonella in feed material.

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    Axmann, Sonja; Kolar, Veronika; Adler, Andreas; Strnad, Irmengard

    2017-11-01

    Salmonella can enter animal stocks via feedstuffs, thus posing not only an infection risk for animals, but also threatening to contaminate food of animal origin and finally humans. Salmonella contamination in feedstuffs is still a recurring and serious issue in animal production (especially for the poultry sector), and is regularly detected upon self-monitoring by feed companies (self-checks) and official inspections authorities. Operators within the feed chain in certain cases need to use hygienic condition enhancers, such as organic acids, to improve the quality of feed for animal nutrition, providing additional guarantees for the protection of animal and public health. The present study investigated the efficiencies of five organic acid preparations. The acid products were added to three different feed materials contaminated with Salmonella (contamination occurred by recontamination in the course of the production process) at seven different inclusion rates (1-7%) and analysed after 1, 2, and 7 days' exposure time using culture method (tenfold analysis). A reliable standard was established for defining a successful decontamination under the prevailing test conditions: 10 Salmonella-negative results out of 10 tested samples (0/10: i.e. 0 positive samples and 10 negative samples). The results demonstrated that the tested preparations showed significant differences with regard to the reduction in Salmonella contamination. At an inclusion rate of 7% of the feed materials, two out of five acid preparations showed an insufficient, very small, decontamination effect, whereas two others had a relatively large partial effect. Reliable decontamination was demonstrated only for one acid preparation, however, subject to the use of the highest acid concentration.

  10. Chlamydospore production and germ-tube formation by auxotrophs of Candida albicans.

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    Balish, E

    1973-04-01

    A prototrophic strain and 21 auxotrophic strains of Candida albicans were assessed for their capacity to produce chlamydospores and germ tubes. All of the mutants were able to produce germ-tubes in human serum but only two mutants produced them in defined medium with L-alpha-amino-n-butyric acid as the sole source of nitrogen. Most auxotrophs were not able to produce chlamydospores on corn meal agar with 1% Tween 80, but they could be induced to do so if the medium was supplemented with their growth requirement(s). Although L-cysteine was able to support the growth of two methionine mutants, it did not support chlamydospore formation when added to corn meal agar with 1% Tween 80. Mutants of C. albicans that do not form chlamydospores could be incorrectly identified in laboratories that rely on chlamydospore formation for identification.

  11. Studies on auxotrophic mutants of Auricularia auricula and Auricularia fuscosucinea induced by irradiation

    International Nuclear Information System (INIS)

    Han Xincai; Yang Xinmei

    1991-01-01

    The induction of auxotrophic mutants of Auricularia auricula and Auricularia fuscosucinea from monokaryotic basidiospore by means of 60 Co-γ ray irradiation was reported. Under the irradiations of 10 krad-200 krad, 9 auxotrophic mutant strains were obtained, including 8 strains of A. auricula and 1 strain of A. fuscosucinea. The frequency of mutagenesis was 2.38 x 10 -3 -44.4 x 10 -3 . It was found that the optimum irradiation dose for A. auricula was 200 krad and for A. fuscosucinea was 10 krad. Biochemical and physiological researches indicated that the colony morphology, the hyphae growth speed, the contents of amino acid and the pattern of esterase isozyme of the mutants were different from those of the prototrophic strains

  12. Genetic recombination in auxotrophic strains of Phanerochaete chrysosporium

    International Nuclear Information System (INIS)

    Krejci, R.

    1987-01-01

    Four auxotrophic strains of ligninolytic basidiomycete Phanerochaete chrysosporium were obtained by UV mutagenesis. The heterokaryotic mycelium formed by complementation of different auxotrophic isolates was able to fruit and produce basidiospores. Prototrophic strains and strains with a recombined set of parental nutritional requirements were isolated from the basidiospore progeny of the heterokaryons. Genetic recombination hence takes place in fruit bodies produced by the heterokaryotic mycelium. (author). 3 tabs., 13 refs

  13. Acidic pH sensing in the bacterial cytoplasm is required for Salmonella virulence.

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    Choi, Jeongjoon; Groisman, Eduardo A

    2016-09-01

    pH regulates gene expression, biochemical activities and cellular behaviors. A mildly acidic pH activates the master virulence regulatory system PhoP/PhoQ in the facultative intracellular pathogen Salmonella enterica serovar Typhimurium. The sensor PhoQ harbors an extracytoplasmic domain implicated in signal sensing, and a cytoplasmic domain controlling activation of the regulator PhoP. We now report that, surprisingly, a decrease in Salmonella's own cytoplasmic pH induces transcription of PhoP-activated genes even when the extracytoplasmic pH remains neutral. Amino acid substitutions in PhoQ's cytoplasmic domain hindered activation by acidic pH and attenuated virulence in mice, but did not abolish activation by low Mg(2+) or the antimicrobial peptide C18G. Conversely, removal of PhoQ's extracytoplasmic domains prevented the response to the latter PhoQ-activating signals but not to acidic pH. PhoP-dependent genes were minimally induced by acidic pH in the non-pathogenic species Salmonella bongori but were activated by low Mg(2+) and C18G as in pathogenic S. enterica. Our findings indicate that the sensor PhoQ enables S. enterica to respond to both host- and bacterial-derived signals that alter its cytoplasmic pH. © 2016 John Wiley & Sons Ltd.

  14. Acid environments affect biofilm formation and gene expression in isolates of Salmonella enterica Typhimurium DT104.

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    O'Leary, Denis; McCabe, Evonne M; McCusker, Matthew P; Martins, Marta; Fanning, Séamus; Duffy, Geraldine

    2015-08-03

    The aim of this study was to examine the survival and potential virulence of biofilm-forming Salmonella Typhimurium DT104 under mild acid conditions. Salmonella Typhimurium DT104 employs an acid tolerance response (ATR) allowing it to adapt to acidic environments. The threat that these acid adapted cells pose to food safety could be enhanced if they also produce biofilms in acidic conditions. The cells were acid-adapted by culturing them in 1% glucose and their ability to form biofilms on stainless steel and on the surface of Luria Bertani (LB) broth at pH7 and pH5 was examined. Plate counts were performed to examine cell survival. RNA was isolated from cells to examine changes in the expression of genes associated with virulence, invasion, biofilm formation and global gene regulation in response to acid stress. Of the 4 isolates that were examined only one (1481) that produced a rigid biofilm in LB broth at pH7 also formed this same structure at pH5. This indicated that the lactic acid severely impeded the biofilm producing capabilities of the other isolates examined under these conditions. Isolate 1481 also had higher expression of genes associated with virulence (hilA) and invasion (invA) with a 24.34-fold and 13.68-fold increase in relative gene expression respectively at pH5 compared to pH7. Although genes associated with biofilm formation had increased expression in response to acid stress for all the isolates this only resulted in the formation of a biofilm by isolate 1481. This suggests that in addition to the range of genes associated with biofilm production at neutral pH, there are genes whose protein products specifically aid in biofilm production in acidic environments. Furthermore, it highlights the potential for the use of lactic acid for the inhibition of Salmonella biofilms. Copyright © 2015 Elsevier B.V. All rights reserved.

  15. Identification and Characterization of Spontaneous Auxotrophic Mutants in Fusarium langsethiae

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    Olga Gavrilova

    2017-03-01

    Full Text Available Analysis of 49 strains of Fusarium langsethiae originating from northern Europe (Russia, Finland, Sweden, UK, Norway, and Latvia revealed the presence of spontaneous auxotrophic mutants that reflect natural intraspecific diversity. Our investigations detected that 49.0% of F. langsethiae strains were auxotrophic mutants for biotin, and 8.2% of the strains required thiamine as a growth factor. They failed to grow on vitamin-free media. For both prototrophic and auxotrophic strains, no growth defect was observed in rich organic media. Without essential vitamins, a significant reduction in the growth of the auxotrophic strains results in a decrease of the formation of T-2 toxin and diacetoxyscirpenol. In addition, all analysed F. langsethiae strains were distinguished into two subgroups based on PCR product sizes. According to our results, 26 and 23 strains of F. langsethiae belong to subgroups I and II respectively. We determined that the deletion in the intergenic spacer (IGS region of the rDNA of F. langsethiae belonging to subgroup II is linked with temperature sensitivity and causes a decrease in strain growth at 30 °C. Four thiamine auxotrophic strains were found in subgroup I, while 21 biotin auxotrophic strains were detected in subgroups II. To the best of our knowledge, the spontaneous mutations in F. langsethiae observed in the present work have not been previously reported.

  16. Host Specificity of Salmonella typhimurium Deoxyribonucleic Acid Restriction and Modification

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    Slocum, Harvey; Boyer, Herbert W.

    1973-01-01

    The restriction and modification genes of Salmonella typhimurium which lie near the thr locus were transferred to a restrictionless mutant of Escherichia coli. These genes were found to be allelic to the E. coli K, B, and A restriction and modification genes. E. coli recombinants with the restriction and modification host specificity of S. typhimurium restricted phage λ that had been modified by each of the seven known host specificities of E. coli at efficiency of plating levels of about 10−2. Phage λ modified with the S. typhimurium host specificity was restricted by six of the seven E. coli host specificities but not by the RII (fi− R-factor controlled) host specificity. It is proposed that the restriction and modification enzymes of this S. typhimurium host specificity have two substrates, one of which is a substrate for the RII host specificity enzymes. PMID:4570605

  17. Antagonistic effect of chosen lactic acid bacteria strains on Salmonella species in meat and fermented sausages.

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    Gomółka-Pawlicka, M; Uradziński, J

    2003-01-01

    The aim of this study was to determine of influence of 15 strains of lactic acid bacteria on the growth of 7 Salmonella spp. strains in model set-ups, and in meat and ripened fermented sausages. The investigations were performed within the framework of three alternate stages which differed in respect to the products studied, the number of Lactobacillus spp. strains and, partly, methodological approach. The ratio between lactic acid bacteria and Salmonella strains studied was, depending on the alternate, 1:1, 1:2 and 2:1, respectively. The investigations also covered the water activity (a(w)) and pH of the tested products. The results obtained are shown in 12 figures and suggest that all the lactic acid bacteria strains used within the framework of the model set-ups showed antagonistic effect on all the Salmonella spp. strains. However, these abilities were not observed with respect to some lactic acid bacteria strains in meat and fermented sausage. The temperature and length of the incubation period of sausages, but not a(w) and pH, were found to have a distinct influence on the antagonistic interaction between the bacteria.

  18. A new and efficient approach for construction of uridine/uracil auxotrophic mutants in the filamentous fungus Aspergillus oryzae using Agrobacterium tumefaciens-mediated transformation.

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    Nguyen, Khuyen Thi; Ho, Quynh Ngoc; Do, Loc Thi Binh Xuan; Mai, Linh Thi Dam; Pham, Duc-Ngoc; Tran, Huyen Thi Thanh; Le, Diep Hong; Nguyen, Huy Quang; Tran, Van-Tuan

    2017-06-01

    Aspergillus oryzae is a filamentous fungus widely used in food industry and as a microbial cell factory for recombinant protein production. Due to the inherent resistance of A. oryzae to common antifungal compounds, genetic transformation of this mold usually requires auxotrophic mutants. In this study, we show that Agrobacterium tumefaciens-mediated transformation (ATMT) method is very efficient for deletion of the pyrG gene in different Aspergillus oryzae wild-type strains to generate uridine/uracil auxotrophic mutants. Our data indicated that all the obtained uridine/uracil auxotrophic transformants, which are 5- fluoroorotic acid (5-FOA) resistant, exist as the pyrG deletion mutants. Using these auxotrophic mutants and the pyrG selectable marker for genetic transformation via A. tumefaciens, we could get about 1060 transformants per 10 6 fungal spores. In addition, these A. oryzae mutants were also used successfully for expression of the DsRed fluorescent reporter gene under control of the A. oryzae amyB promoter by the ATMT method, which resulted in obvious red transformants on agar plates. Our work provides a new and effective approach for constructing the uridine/uracil auxotrophic mutants in the importantly industrial fungus A. oryzae. This strategy appears to be applicable to other filamentous fungi to develop similar genetic transformation systems based on auxotrophic/nutritional markers for food-grade recombinant applications.

  19. Aerogenic vaccination with a Burkholderia mallei auxotroph protects against aerosol-initiated glanders in mice.

    Science.gov (United States)

    Ulrich, Ricky L; Amemiya, Kei; Waag, David M; Roy, Chad J; DeShazer, David

    2005-03-14

    Burkholderia mallei is an obligate mammalian pathogen that causes the zoonotic disease glanders. Two live attenuated B. mallei strains, a capsule mutant and a branched-chain amino acid auxotroph, were evaluated for use as vaccines against aerosol-initiated glanders in mice. Animals were aerogenically vaccinated and serum samples were obtained before aerosol challenge with a high-dose (>300 times the LD50) of B. mallei ATCC 23344. Mice vaccinated with the capsule mutant developed a Th2-like Ig subclass antibody response and none survived beyond 5 days. In comparison, the auxotrophic mutant elicited a Th1-like Ig subclass antibody response and 25% of the animals survived for 1 month postchallenge. After a low-dose (5 times the LD50) aerosol challenge, the survival rates of auxotroph-vaccinated and unvaccinated animals were 50 and 0%, respectively. Thus, live attenuated strains that promote a Th1-like Ig response may serve as promising vaccine candidates against aerosol infection with B. mallei.

  20. Generation of a Uracil Auxotroph Strain of the Probiotic Yeast Saccharomyces boulardii as a Host for the Recombinant Protein Production

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    Hamedi, Hassan; Misaghi, Ali; Modarressi, Mohammad Hossein; Salehi, Taghi Zahraei; Khorasanizadeh, Dorsa; Khalaj, Vahid

    2013-01-01

    Background Saccharomyces boulardii (S. boulardii) is the best known probiotic yeast. The genetic engineering of this probiotic strain requires the availability of appropriate mutants to accept various gene constructs carrying different selection markers. As the auxotrophy selection markers are under focus, we have generated a ura3 auxotroph mutant of S. boulardii for use in further genetic manipulations. Methods Classical UV mutagenesis was used for the generation of auxotroph mutants. The mutants were selected in the presence of 5-FOA (5-Fluoroorotic acid), uracil and uridine. Uracil auxotrophy phenotype was confirmed by the ability of mutants to grow in the presence of uracil and the lack of growth in the absence of this compound. To test whether the uracil auxotrophy phenotype is due to the inactivation of URA3, the mutants were transformed with a plasmid carrying the gene. An in vitro assay was used for the analysis of acid and bile resistance capacity of these mutants. Results Three mutants were found to be ura3 auxotroph as they were able to grow only in the presence of uracil. When the URA3 gene was added, these mutants were able to grow normally in the absence of uracil. Further in vitro analysis showed that the acid and bile resistance capacity of one of these mutants is intact and similar to the wild type. Conclusion A uracil auxotroph mutant of the probiotic yeast, S. boulardii, was generated and characterized. This auxotroph strain may have potential applications in the production and delivery of the recombinant pharmacuetics into the intestinal lumen. PMID:23626874

  1. Dietary proteins extend the survival of salmonella dublin in a gastric Acid environment

    DEFF Research Database (Denmark)

    Birk, Tina; Kristensen, Kim; Harboe, Anne

    2012-01-01

    The pH of the human stomach is dynamic and changes over time, depending on the composition of the food ingested and a number of host-related factors such as age. To evaluate the number of bacteria surviving the gastric acid barrier, we have developed a simple gastric acid model, in which we...... mimicked the dynamic pH changes in the human stomach. In the present study, model gastric fluid was set up to imitate pH dynamics in the stomachs of young and elderly people after ingestion of a standard meal. To model a serious foodborne pathogen, we followed the survival of Salmonella enterica serotype...

  2. Mutagenicity of irradiated solutions of nuclei acid bases and nucleosides in Salmonella typhimurium

    International Nuclear Information System (INIS)

    Wilmer, J.; Schubert, J.

    1981-01-01

    Solutions of nucleic acid bases, nucleosides and a nucleotide, saturated with either N 2 , N 2 O or O 2 , were irradiated and tested for mutagenicity towards Salmonella typhimurium, with and without pre-incubation. Irradiated solutions of the nuclei acid bases were all non-mutagenic. Irradiated solutions of the nucleosides showed mutagenicity in S. typhimurium TA100 (pre-incubation assay). Generally, the mutagenicity followed the order: N 2 O > N 2 > O 2 . The results show that the formation of mutagenic radiolytic products is initiated by attack of mainly solutions of the nucleotide thymidine-5'-monophosphate, no mutagenicity could be detected. (orig.)

  3. Lactic acid bacteria from chicken carcasses with inhibitory activity against Salmonella spp. and Listeria monocytogenes.

    Science.gov (United States)

    Sakaridis, I; Soultos, N; Dovas, C I; Papavergou, E; Ambrosiadis, I; Koidis, P

    2012-02-01

    This study was conducted to isolate psychrotrophic lactic acid bacteria (LAB) from chicken carcasses with inhibitory activity against strains of Salmonella spp. and Listeria monocytogenes. A total of 100 broiler samples were examined for the presence of LAB. Ninety-two LAB isolates that showed antimicrobial effects against Salmonella spp. and L. monocytogenes were further analysed to examine their LAB (Gram-positive, catalase negative, oxidase negative) and psychrotrophic characteristics (ability to grow at 7 °C). Fifty isolates were further selected and identified initially using standard biochemical tests in miniature (Micro-kits API CH 50) and then by sequencing of the 16s-23s rRNA gene boundary region (Intergenic Spacer Region). By molecular identification, these isolates were classified into 5 different LAB species: Lactobacillus salivarius, Lactobacillus reuteri, Lactobacillus johnsonii, Pediococcus acidilactici, and Lactobacillus paralimentarius. None of the isolates produced tyramine or histamine. Copyright © 2011 Elsevier Ltd. All rights reserved.

  4. Preliminary Transcriptome Analysis of Mature Biofilm and Planktonic Cells of Salmonella Enteritidis Exposure to Acid Stress

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    Kun Jia

    2017-09-01

    Full Text Available Salmonella has emerged as a well-recognized food-borne pathogen, with many strains able to form biofilms and thus cause cross-contamination in food processing environments where acid-based disinfectants are widely encountered. In the present study, RNA sequencing was employed to establish complete transcriptome profiles of Salmonella Enteritidis in the forms of planktonic and biofilm-associated cells cultured in Tryptic Soytone Broth (TSB and acidic TSB (aTSB. The gene expression patterns of S. Enteritidis significantly differed between biofilm-associated and planktonic cells cultivated under the same conditions. The assembled transcriptome of S. Enteritidis in this study contained 5,442 assembled transcripts, including 3,877 differentially expressed genes (DEGs identified in biofilm and planktonic cells. These DEGs were enriched in terms such as regulation of biological process, metabolic process, macromolecular complex, binding and transferase activity, which may play crucial roles in the biofilm formation of S. Enteritidis cultivated in aTSB. Three significant pathways were observed to be enriched under acidic conditions: bacterial chemotaxis, porphyrin-chlorophyll metabolism and sulfur metabolism. In addition, 15 differentially expressed novel non-coding small RNAs (sRNAs were identified, and only one was found to be up-regulated in mature biofilms. This preliminary study of the S. Enteritidis transcriptome serves as a basis for future investigations examining the complex network systems that regulate Salmonella biofilm in acidic environments, which provide information on biofilm formation and acid stress interaction that may facilitate the development of novel disinfection procedures in the food processing industry.

  5. Identification of auxotrophic mutants of the yeast Kluyveromyces marxianus by non-homologous end joining-mediated integrative transformation with genes from Saccharomyces cerevisiae.

    Science.gov (United States)

    Yarimizu, Tohru; Nonklang, Sanom; Nakamura, Junpei; Tokuda, Shuya; Nakagawa, Takaaki; Lorreungsil, Sasithorn; Sutthikhumpha, Surasit; Pukahuta, Charida; Kitagawa, Takao; Nakamura, Mikiko; Cha-Aim, Kamonchai; Limtong, Savitree; Hoshida, Hisashi; Akada, Rinji

    2013-12-01

    The isolation and application of auxotrophic mutants for gene manipulations, such as genetic transformation, mating selection and tetrad analysis, form the basis of yeast genetics. For the development of these genetic methods in the thermotolerant fermentative yeast Kluyveromyces marxianus, we isolated a series of auxotrophic mutants with defects in amino acid or nucleic acid metabolism. To identify the mutated genes, linear DNA fragments of nutrient biosynthetic pathway genes were amplified from Saccharomyces cerevisiae chromosomal DNA and used to directly transform the K. marxianus auxotrophic mutants by random integration into chromosomes through non-homologous end joining (NHEJ). The appearance of transformant colonies indicated that the specific S. cerevisiae gene complemented the K. marxianus mutant. Using this interspecific complementation approach with linear PCR-amplified DNA, we identified auxotrophic mutations of ADE2, ADE5,7, ADE6, HIS2, HIS3, HIS4, HIS5, HIS6, HIS7, LYS1, LYS2, LYS4, LYS9, LEU1, LEU2, MET2, MET6, MET17, TRP3, TRP4 and TRP5 without the labour-intensive requirement of plasmid construction. Mating, sporulation and tetrad analysis techniques for K. marxianus were also established. With the identified auxotrophic mutant strains and S. cerevisiae genes as selective markers, NHEJ-mediated integrative transformation with PCR-amplified DNA is an attractive system for facilitating genetic analyses in the yeast K. marxianus. Copyright © 2013 John Wiley & Sons, Ltd.

  6. Branched-chain amino acid supplementation promotes aerobic growth of Salmonella Typhimurium under nitrosative stress conditions.

    Science.gov (United States)

    Park, Yoon Mee; Lee, Hwa Jeong; Jeong, Jae-Ho; Kook, Joong-Ki; Choy, Hyon E; Hahn, Tae-Wook; Bang, Iel Soo

    2015-12-01

    Nitric oxide (NO) inactivates iron-sulfur enzymes in bacterial amino acid biosynthetic pathways, causing amino acid auxotrophy. We demonstrate that exogenous supplementation with branched-chain amino acids (BCAA) can restore the NO resistance of hmp mutant Salmonella Typhimurium lacking principal NO-metabolizing enzyme flavohemoglobin, and of mutants further lacking iron-sulfur enzymes dihydroxy-acid dehydratase (IlvD) and isopropylmalate isomerase (LeuCD) that are essential for BCAA biosynthesis, in an oxygen-dependent manner. BCAA supplementation did not affect the NO consumption rate of S. Typhimurium, suggesting the BCAA-promoted NO resistance independent of NO metabolism. BCAA supplementation also induced intracellular survival of ilvD and leuCD mutants at wild-type levels inside RAW 264.7 macrophages that produce constant amounts of NO regardless of varied supplemental BCAA concentrations. Our results suggest that the NO-induced BCAA auxotrophy of Salmonella, due to inactivation of iron-sulfur enzymes for BCAA biosynthesis, could be rescued by bacterial taking up exogenous BCAA available in oxic environments.

  7. In vitro quantitative analysis of Salmonella typhimurium preference for amino acids secreted by human breast tumor

    Science.gov (United States)

    Choi, Eunpyo; Maeng, Bohee; Lee, Jae-hun; Chang, Hyung-kwan; Park, Jungyul

    2016-12-01

    Bacterial therapies have been paid significant attentions by their ability to penetrate deep into the solid tumor tissue and its propensity to naturally accumulate in tumors of living animals. Understanding the actual mechanism for bacteria to target the tumor is therapeutically crucial but is poorly understood. We hypothesized that amino acids released from the specific tumors induced bacteria to those tumors and the experiments for chemotactic response of bacteria toward the cancer secreting amino acids was then performed by using the diffusion based multiple chemical gradient generator constructed by in situ self-assembly of microspheres. The quantitative analysis was carried out by comparison of intensity using green fluorescent protein (GFP) tagged Salmonella typhimurium ( S. typhimurium) in the gradient generator, which showed the clear preference to the released amino acids, especially from breast cancer patients. The understanding chemotaxis toward the cancer secreting amino acids is essential for controlling S. typhimurium targeting in tumors and will allow for the development of bacterial therapies.

  8. Selected lactic acid-producing bacterial isolates with the capacity to reduce Salmonella translocation and virulence gene expression in chickens.

    Directory of Open Access Journals (Sweden)

    Xiaojian Yang

    Full Text Available BACKGROUND: Probiotics have been used to control Salmonella colonization/infection in chickens. Yet the mechanisms of probiotic effects are not fully understood. This study has characterized our previously-selected lactic acid-producing bacterial (LAB isolates for controlling Salmonella infection in chickens, particularly the mechanism underlying the control. METHODOLOGY/PRINCIPAL FINDINGS: In vitro studies were conducted to characterize 14 LAB isolates for their tolerance to low pH (2.0 and high bile salt (0.3-1.5% and susceptibility to antibiotics. Three chicken infection trials were subsequently carried out to evaluate four of the isolates for reducing the burden of Salmonella enterica serovar Typhimurium in the broiler cecum. Chicks were gavaged with LAB cultures (10(6-7 CFU/chick or phosphate-buffered saline (PBS at 1 day of age followed by Salmonella challenge (10(4 CFU/chick next day. Samples of cecal digesta, spleen, and liver were examined for Salmonella counts on days 1, 3, or 4 post-challenge. Salmonella in the cecum from Trial 3 was also assessed for the expression of ten virulence genes located in its pathogenicity island-1 (SPI-1. These genes play a role in Salmonella intestinal invasion. Tested LAB isolates (individuals or mixed cultures were unable to lower Salmonella burden in the chicken cecum, but able to attenuate Salmonella infection in the spleen and liver. The LAB treatments also reduced almost all SPI-1 virulence gene expression (9 out of 10 in the chicken cecum, particularly at the low dose. In vitro treatment with the extracellular culture fluid from a LAB culture also down-regulated most SPI-1 virulence gene expression. CONCLUSIONS/SIGNIFICANCE: The possible correlation between attenuation of Salmonella infection in the chicken spleen and liver and reduction of Salmonella SPI-1 virulence gene expression in the chicken cecum by LAB isolates is a new observation. Suppression of Salmonella virulence gene expression in

  9. Emerging nalidixic acid and ciprofloxacin resistance in non-typhoidal Salmonella isolated from patients having acute diarrhoeal disease

    International Nuclear Information System (INIS)

    Panhotra, B.R.; Saxena, A.K.; Al-Arabi, Ali M.

    2004-01-01

    Non-typhoidal Salmonella are one of the key etiological agents of diarrhoeal disease. The appearence of multiple drung resistance along with resistance to quinolones in this bacterium poses a serious therapeutic problem. We determined the prevalence of nalidixic acid and ciprofloxacin resistance in non-typhodial Salmonella isolated from faecal samples of patients with acute diarroheal disease attending the outpatient and inpatient department of a hospital in Saudi Arabia during the years 1999 to 2002. Non-typhodial Salmonella were isolated from faecal samples. Antimicrobial susceptibility was tested by the disc diffusion test. MICs to nalidixic acid and ciprofloxacinwere determined by the agar dilution method. During the study period , 524 strains of non-typhoidal Salmonella were isolated. Strains belonging to serogroup C1were the commonest (41.4%) followed by serogroups B and D (15.6% and 14.5%, respectively). Resistance to ampicillin was observed in 22.9% and to trimethoprim/sulphamethoxazole in 18.5%of the strains. Nalidixic acid resistance was encounterd in 9.9% and ciprofloxacin esistance in 2.3% of the strains. Resistance to nalidixic acid significantly increased from 0.1% in 1999 to 5.51% in 2002 ( p=0.0007)and ciprofloxacin resistance increased significantly from 0.1% in 1999 to 0.9% in 2002( p=0.0001). MICs to nalidixic acid and ciprofloxacin were determined among 29 nalidixic acid-resistant strains of non-typhoidal salmonella isolated during 2002. The MIC was >256 ug /ml to nalidixic acid and 8 to 16 ug/ml to ciprofloxacin. The increasing rate of antimicrobial resistance encountered among non-tyophoidal Salmonella necessiate the judicious use of these drugs in humans. Moreover, these findings support the concern that the use of quinolones in animal feed may lead to an increasein resistance and should should be restricted. (author)

  10. Buffer capacity of food components influences the acid tolerance response in Salmonella Typhimurium during simulated gastric passage

    DEFF Research Database (Denmark)

    Aabo, Søren; Buschhardt, Tasja; Hansen, Tina Beck

    2014-01-01

    Food composition, buffer capacity, and fat and protein content have been shown to effect the gastric acid survival of pathogens (Waterman & Small 1998). In this study, simple food-model substances with different buffer capacities were investigated for their ability to support survival of stationary...... Heart Infusion Broth having a higher buffer capacity. We suggest this to be associated with a varying ability of Salmonella Typhimurium to mount a stationary phase acid tolerance response (ATR) depending on the buffer capacity of the food vehicle....... phase Salmonella Typhimurium during simulated gastric acid passage. We used a computer-controlled fermentor to employ pH changes in synthetic gastric fluid, mimicking the dynamic pH during gastric passage. In order to minimise variation, Salmonella enterica serovar Typhimurium was contained in dialysis...

  11. Acid tolerance in Salmonella typhimurium induced by culturing in the presence of organic acids at different growth temperatures.

    Science.gov (United States)

    Alvarez-Ordóñez, Avelino; Fernández, Ana; Bernardo, Ana; López, Mercedes

    2010-02-01

    The influence of growth temperature and acidification of the culture medium up to pH 4.25 with acetic, citric, lactic and hydrochloric acids on the growth and subsequent acid resistance at pH 3.0 of Salmonella typhimurium CECT 443 was studied. The minimum pH value which allowed for S. typhimurium growth within the temperature range of 25-37 degrees C was 4.5 when the pH was reduced using citric and hydrochloric acids, and 5.4 and 6.4 when lactic acid and acetic acid were used, respectively. At high (45 degrees C) or low (10 degrees C) temperatures, the growth pH boundary was increased about 1 pH unit. The growth temperature markedly modified the acid resistance of the resulting cells. In all cases, D-values were lower for cells grown at 10 degrees C and significantly increased with increasing growth temperature up to 37 degrees C, at which D-values obtained were up to 10 times higher. Cells grown at 45 degrees C showed D-values similar to those found for cells grown at 25 degrees C. The growth of cells in acidified media, regardless of the pH value, caused an increase in their acid resistance at the four incubation temperatures, although the magnitude of the Acid Tolerance Response (ATR) observed depended on the growth temperature. Acid adapted cultures at 10 degrees C showed D-values ranging from 5.75 to 6.91 min, which turned out to be about 2 times higher than those corresponding to non-acid adapted cultures, while higher temperatures induced an increase in D-values of at least 3.5 times. Another finding was that, while at 10 and 45 degrees C no significant differences among the effect of the different acids tested in inducing an ATR were observed, when cells were grown at 25 and 37 degrees C citric acid generally turned out to be the acid which induced the strongest ATR. Results obtained in this study show that growth temperature is an important factor affecting S. typhimurium acid resistance and could contribute to find new strategies based on intelligent

  12. Sensing and adaptation to low pH mediated by inducible amino acid decarboxylases in Salmonella.

    Science.gov (United States)

    Viala, Julie P M; Méresse, Stéphane; Pocachard, Bérengère; Guilhon, Aude-Agnès; Aussel, Laurent; Barras, Frédéric

    2011-01-01

    During the course of infection, Salmonella enterica serovar Typhimurium must successively survive the harsh acid stress of the stomach and multiply into a mild acidic compartment within macrophages. Inducible amino acid decarboxylases are known to promote adaptation to acidic environments. Three low pH inducible amino acid decarboxylases were annotated in the genome of S. Typhimurium, AdiA, CadA and SpeF, which are specific for arginine, lysine and ornithine, respectively. In this study, we characterized and compared the contributions of those enzymes in response to acidic challenges. Individual mutants as well as a strain deleted for the three genes were tested for their ability (i) to survive an extreme acid shock, (ii) to grow at mild acidic pH and (iii) to infect the mouse animal model. We showed that the lysine decarboxylase CadA had the broadest range of activity since it both had the capacity to promote survival at pH 2.3 and growth at pH 4.5. The arginine decarboxylase AdiA was the most performant in protecting S. Typhimurium from a shock at pH 2.3 and the ornithine decarboxylase SpeF conferred the best growth advantage under anaerobiosis conditions at pH 4.5. We developed a GFP-based gene reporter to monitor the pH of the environment as perceived by S. Typhimurium. Results showed that activities of the lysine and ornithine decarboxylases at mild acidic pH did modify the local surrounding of S. Typhimurium both in culture medium and in macrophages. Finally, we tested the contribution of decarboxylases to virulence and found that these enzymes were dispensable for S. Typhimurium virulence during systemic infection. In the light of this result, we examined the genomes of Salmonella spp. normally responsible of systemic infection and observed that the genes encoding these enzymes were not well conserved, supporting the idea that these enzymes may be not required during systemic infection.

  13. Sensing and adaptation to low pH mediated by inducible amino acid decarboxylases in Salmonella.

    Directory of Open Access Journals (Sweden)

    Julie P M Viala

    Full Text Available During the course of infection, Salmonella enterica serovar Typhimurium must successively survive the harsh acid stress of the stomach and multiply into a mild acidic compartment within macrophages. Inducible amino acid decarboxylases are known to promote adaptation to acidic environments. Three low pH inducible amino acid decarboxylases were annotated in the genome of S. Typhimurium, AdiA, CadA and SpeF, which are specific for arginine, lysine and ornithine, respectively. In this study, we characterized and compared the contributions of those enzymes in response to acidic challenges. Individual mutants as well as a strain deleted for the three genes were tested for their ability (i to survive an extreme acid shock, (ii to grow at mild acidic pH and (iii to infect the mouse animal model. We showed that the lysine decarboxylase CadA had the broadest range of activity since it both had the capacity to promote survival at pH 2.3 and growth at pH 4.5. The arginine decarboxylase AdiA was the most performant in protecting S. Typhimurium from a shock at pH 2.3 and the ornithine decarboxylase SpeF conferred the best growth advantage under anaerobiosis conditions at pH 4.5. We developed a GFP-based gene reporter to monitor the pH of the environment as perceived by S. Typhimurium. Results showed that activities of the lysine and ornithine decarboxylases at mild acidic pH did modify the local surrounding of S. Typhimurium both in culture medium and in macrophages. Finally, we tested the contribution of decarboxylases to virulence and found that these enzymes were dispensable for S. Typhimurium virulence during systemic infection. In the light of this result, we examined the genomes of Salmonella spp. normally responsible of systemic infection and observed that the genes encoding these enzymes were not well conserved, supporting the idea that these enzymes may be not required during systemic infection.

  14. Inactivation of Salmonella in tomato stem scars by organic acid wash and chitosan-allyl isothiocyanate coating

    Science.gov (United States)

    The objective of this study was to evaluate inactivation of inoculated Salmonella enterica on tomato stem scars exploiting integrated treatment of organic acid wash (AW) followed by chitosan-allyl isothiocyanate (CT-AIT) coating. The treatment effect on microbial loads and fruit quality during 21 d...

  15. Effects and interactions of gallic acid, eugenol and temperature on thermal inactivation of Salmonella spp. in ground chicken

    Science.gov (United States)

    The combined effects of heating temperature (55 to 65C), gallic acid (0 to 2.0%), and eugenol (0 to 2.0%) on thermal inactivation of Salmonella in ground chicken were assessed. Thermal death times were determined in bags submerged in a heated water bath maintained at various set temperatures, follo...

  16. Buffer capacity of food components influences the acid tolerance response in Salmonella Typhimurium during simulated gastric passage

    DEFF Research Database (Denmark)

    Henriksen, Sidsel; Buschhardt, Tasja; Hansen, Tina Beck

    2014-01-01

    tubes, enabling simultaneous testing of biological triplicates under varying conditions. Surprisingly, we found that less buffered media provided higher protection of Salmonella, compared to media with high buffer capacity. By investigating the relative gene expression of rpoS and ompR encoding for two...... Heart Infusion Broth having a higher buffer capacity. We suggest this to be associated with a varying ability of Salmonella Typhimurium to mount a stationary phase acid tolerance response (ATR) depending on the buffer capacity of the food vehicle....

  17. Evaluation of the addition of organic acids in the feed and/or water for broilers and the subsequent recovery of Salmonella Typhimurium from litter and ceca.

    Science.gov (United States)

    Bourassa, D V; Wilson, K M; Ritz, C R; Kiepper, B K; Buhr, R J

    2018-01-01

    Three separate broiler Salmonella Typhimurium challenge experiments were conducted evaluating efficacy of formic and propionic acid feed supplements to suppress environmental and cecal Salmonella Typhimurium prevalence. In experiment 1, broilers were provided feed with 1 kg/ton formic acid or 5 kg/ton propionic acid feed additives or a basal control diet. At the day of placement, half of the pens were inoculated with seeder chicks orally challenged with a marker strain of Salmonella Typhimurium and to yield challenged and adjacent nonchallenged pens. No differences in weekly litter samples or cecal Salmonella prevalence at 3 or 6 wk among feeding treatments were detected. In experiment 2, treatments were: 2 kg/ton propionic acid in feed, 1.0 mL/L formic acid in water, both propionic acid in feed and formic acid in water, and a basal control. Every pen was challenged with seeder chicks inoculated with Salmonella Typhimurium. By 6 wk all pens maintained detectable litter Salmonella, and broilers provided both propionic acid in feed and formic acid in water had the lowest cecal recovery (35%), compared to the control (60%). In experiment 3, treatments were: formic acid at 4 or 6 kg/ton from wk 0 to 6 or for only the last wk, propionic acid at 5 or 10 kg/ton for only the last wk, and a basal control. Each pen was challenged with Salmonella Typhimurium inoculated seeder chicks. By 6 wk, broilers fed formic acid (4 kg/ton) for the entire growout had no Salmonella-positive ceca (0/30). All treatments that provided acid supplemented feed for only the last wk had 3-13% Salmonella-positive ceca. These experiments indicate that adding formic acid to broiler feed appears to prevent Salmonella colonization from challenge pens entering into the adjacent nonchallenge pens. Feeding formic acid (4 kg/ton) for 6 wk resulted in no recovery of Salmonella from ceca compared to the control prevalence of 17%. Published by Oxford University Press on behalf of Poultry Science

  18. Exploiting E. coli auxotrophs for leucine, valine, and threonine specific methyl labeling of large proteins for NMR applications

    Energy Technology Data Exchange (ETDEWEB)

    Monneau, Yoan R. [Rutgers University, Center for Integrative Proteomics Research and Department of Chemistry and Chemical Biology (United States); Ishida, Yojiro [Rutgers University, Center for Advanced Biotechnology and Medicine (United States); Rossi, Paolo; Saio, Tomohide; Tzeng, Shiou-Ru [Rutgers University, Center for Integrative Proteomics Research and Department of Chemistry and Chemical Biology (United States); Inouye, Masayori, E-mail: inouye@cabm.rutgers.edu [Rutgers University, Center for Advanced Biotechnology and Medicine (United States); Kalodimos, Charalampos G., E-mail: ckalodim@umn.edu [Rutgers University, Center for Integrative Proteomics Research and Department of Chemistry and Chemical Biology (United States)

    2016-06-15

    A simple and cost effective method to independently and stereo-specifically incorporate [{sup 1}H,{sup 13}C]-methyls in Leu and Val in proteins is presented. Recombinant proteins for NMR studies are produced using a tailored set of auxotrophic E. coli strains. NMR active isotopes are routed to either Leu or Val methyl groups from the commercially available and scrambling-free precursors α-ketoisovalerate and acetolactate. The engineered strains produce deuterated proteins with stereospecific [{sup 1}H,{sup 13}C]-methyl labeling separately at Leu or Val amino acids. This is the first method that achieves Leu-specific stereospecific [{sup 1}H,{sup 13}C]-methyl labeling of proteins and scramble-free Val-specific labeling. Use of auxotrophs drastically decreases the amount of labeled precursor required for expression without impacting the yield. The concept is extended to Thr methyl labeling by means of a Thr-specific auxotroph that provides enhanced efficiency for use with the costly L-[4-{sup 13}C,2,3-{sup 2}H{sub 2},{sup 15}N]-Thr reagent. The Thr-specific strain allows for the production of Thr-[{sup 13}CH{sub 3}]{sup γ2} labeled protein with an optimal isotope incorporation using up to 50 % less labeled Thr than the traditional E. coli strain without the need for {sup 2}H-glycine to prevent scrambling.

  19. Antibacterial effect of roselle extracts (Hibiscus sabadariffa), sodium hypochlorite and acetic acid against multidrug-resistant Salmonella strains isolated from tomatoes.

    Science.gov (United States)

    Gutiérrez-Alcántara, E J; Rangel-Vargas, E; Gómez-Aldapa, C A; Falfan-Cortes, R N; Rodríguez-Marín, M L; Godínez-Oviedo, A; Cortes-López, H; Castro-Rosas, J

    2016-02-01

    Antibiotic-resistant Salmonella strains were isolated from saladette and red round type tomatoes, and an analysis done of the antibacterial activity of roselle calyx extracts against any of the identified strains. One hundred saladette tomato samples and 100 red round tomato samples were collected from public markets. Each sample consisted of four whole tomatoes. Salmonella was isolated from the samples by conventional culture procedure. Susceptibility to 16 antibiotics was tested for the isolated Salmonella strains by standard test. The antibacterial effect of four roselle calyx extracts (water, methanol, acetone and ethyl acetate), sodium hypochlorite and acetic acid against antibiotic-resistant Salmonella isolates was evaluated on contaminated tomatoes. Twenty-four Salmonella strains were isolated from 12% of each tomato type. Identified Salmonella serotypes were Typhimurium and Typhi. All isolated strains exhibited resistance to at least three antibiotics and some to as many as 12. Over contaminated tomatoes, the roselle calyx extracts produced a greater reduction (2-2·6 log) in antibiotic-resistant Salmonella strain concentration than sodium hypochlorite and acetic acid. The presence of multidrug-resistant Salmonella in vegetables is a significant public health concern. Multidrug-resistant Salmonella strains were isolated from raw tomatoes purchased in public markets in Mexico and challenged with roselle Hibiscus sabdariffa calyx extracts, sodium hypochlorite and acetic acid. On tomatoes, the extracts caused a greater reduction in the concentration of antibiotic-resistant Salmonella strains than sodium hypochlorite and acetic acid. Roselle calyx extracts are a potentially useful addition to disinfection procedures of raw tomatoes in the field, processing plants, restaurants and homes. © 2015 The Society for Applied Microbiology.

  20. Acidic pH and divalent cation sensing by PhoQ are dispensable for systemic salmonellae virulence.

    Science.gov (United States)

    Hicks, Kevin G; Delbecq, Scott P; Sancho-Vaello, Enea; Blanc, Marie-Pierre; Dove, Katja K; Prost, Lynne R; Daley, Margaret E; Zeth, Kornelius; Klevit, Rachel E; Miller, Samuel I

    2015-05-23

    Salmonella PhoQ is a histidine kinase with a periplasmic sensor domain (PD) that promotes virulence by detecting the macrophage phagosome. PhoQ activity is repressed by divalent cations and induced in environments of acidic pH, limited divalent cations, and cationic antimicrobial peptides (CAMP). Previously, it was unclear which signals are sensed by salmonellae to promote PhoQ-mediated virulence. We defined conformational changes produced in the PhoQ PD on exposure to acidic pH that indicate structural flexibility is induced in α-helices 4 and 5, suggesting this region contributes to pH sensing. Therefore, we engineered a disulfide bond between W104C and A128C in the PhoQ PD that restrains conformational flexibility in α-helices 4 and 5. PhoQ(W104C-A128C) is responsive to CAMP, but is inhibited for activation by acidic pH and divalent cation limitation. phoQ(W104C-A128C) Salmonella enterica Typhimurium is virulent in mice, indicating that acidic pH and divalent cation sensing by PhoQ are dispensable for virulence.

  1. aroA-Deficient Salmonella enterica Serovar Typhimurium Is More Than a Metabolically Attenuated Mutant

    Science.gov (United States)

    Frahm, Michael; Kocijancic, Dino; Rohde, Manfred; Eckweiler, Denitsa; Bielecka, Agata; Bueno, Emilio; Cava, Felipe; Abraham, Wolf-Rainer; Curtiss, Roy; Häussler, Susanne; Erhardt, Marc; Weiss, Siegfried

    2016-01-01

    ABSTRACT Recombinant attenuated Salmonella enterica serovar Typhimurium strains are believed to act as powerful live vaccine carriers that are able to elicit protection against various pathogens. Auxotrophic mutations, such as a deletion of aroA, are commonly introduced into such bacteria for attenuation without incapacitating immunostimulation. In this study, we describe the surprising finding that deletion of aroA dramatically increased the virulence of attenuated Salmonella in mouse models. Mutant bacteria lacking aroA elicited increased levels of the proinflammatory cytokine tumor necrosis factor alpha (TNF-α) after systemic application. A detailed genetic and phenotypic characterization in combination with transcriptomic and metabolic profiling demonstrated that ΔaroA mutants display pleiotropic alterations in cellular physiology and lipid and amino acid metabolism, as well as increased sensitivity to penicillin, complement, and phagocytic uptake. In concert with other immunomodulating mutations, deletion of aroA affected flagellin phase variation and gene expression of the virulence-associated genes arnT and ansB. Finally, ΔaroA strains displayed significantly improved tumor therapeutic activity. These results highlight the importance of a functional shikimate pathway to control homeostatic bacterial physiology. They further highlight the great potential of ΔaroA-attenuated Salmonella for the development of vaccines and cancer therapies with important implications for host-pathogen interactions and translational medicine. PMID:27601574

  2. Liver function and bacteriology of organs in broiler inoculated with nalidixic acid-resistant Salmonella Typhimurium and treated with organic acids

    Directory of Open Access Journals (Sweden)

    Tatiane M. Rocha

    2013-07-01

    Full Text Available AbAns etxrpaecritment was carried out with 630 one-day-old chicks to evaluate the effects of organic acids when birds were experimentally inoculated with Salmonella Typhimurium. Liver damage and the persistence of the bacterium in the organs were evaluated as well. Broilers were distributed in a completely randomised experimental design in a 3×2 factorial arrangement of six treatments with seven replicates of 15 birds each. Birds were inoculated with saline solution or the bacterium via gavage at 1 day of age, or were offered a feed containing or not the organic acid blend for the period of 7 to 14 days of age. A dose of 5.0x102 colony-forming units (CFU/0.5 mL of Salmonella Typhimurium was used for inoculation both via gavage and feed. The parameters evaluated are weight, liver histopathology, liver and serum biochemistry, and bacteriological analyses of the caeca, crop, spleen, and liver and heart pool. At 21 and 28 days of age, the liver of the non-inoculated groups was significantly lighter as compared to the other treatments. Birds fed organic acids presented lower bacterial isolation rates in all organs tested. Birds inoculated in the crop and treated with organic acids presented lower E. coli CFU counts (P<0.05. Birds inoculated with Salmonella presented significant changes (P<0.05 in liver enzymes, as detected by serum biochemistry, and in liver histopathology. It was concluded that organic acids effectively controlled Salmonella Typhimurium and did not cause any liver damage.

  3. Characterization of a Salmonella typhimurium mutant defective in phosphoribosylpyrophosphate synthetase

    DEFF Research Database (Denmark)

    Jochimsen, Bjarne; Hove-Jensen, Bjarne; Garber, Bruce B.

    1985-01-01

    This study describes the isolation and characterization of a mutant (strain GP122) of Salmonella typhimurium with a partial deficiency of phosphoribosylpyrophosphate (PRPP) synthetase activity. This strain was isolated in a purE deoD gpt purine auxotroph by a procedure designed to select guanosin...

  4. Inactivation of Salmonella enterica and Listeria monocytogenes in cantaloupe puree by high hydrostatic pressure with/without added ascorbic acid.

    Science.gov (United States)

    Mukhopadhyay, Sudarsan; Sokorai, Kimberly; Ukuku, Dike; Fan, Xuetong; Juneja, Vijay; Sites, Joseph; Cassidy, Jennifer

    2016-10-17

    The objective of this research was to evaluate and develop a method for inactivation of Salmonella enterica and Listeria monocytogenes in cantaloupe puree (CP) by high hydrostatic pressure (HHP). Cantaloupe being the most netted varieties of melons presents a greater risk of pathogen transmission. Freshly prepared CP with or without 0.1% ascorbic acid (AA) was inoculated with a bacterial cocktail composed of a three serotype mixture of S. enterica (S. Poona, S. Newport H1275 and S. Stanley H0558) and a mixture of three strains of L. monocytogenes (Scott A, 43256 and 51742) to a population of ca. 10(8)CFU/g. Double sealed and double bagged inoculated CP (ca. 5g) were pressure treated at 300, 400 and 500MPa at 8°C and 15°C for 5min. Data indicated increased inactivation of both Salmonella and Listeria spp. with higher pressure. Log reduction for CP at 300MPa, 8°C for 5min was 2.4±0.2 and 1.6±0.5logCFU/g for Salmonella and Listeria, respectively. Survivability of the pathogens was significantly compromised at 400MPa and 8°C, inactivating 4.5±0.3logCFU/g of Salmonella and 3.0±0.4logCFU/g of Listeria spp. Complete inactivation of the pathogens in the puree (log reduction >6.7logCFU/g), with or without AA, was achieved when the pressure was further increased to 500MPa, except that for Listeria containing no AA at 8°C. Listeria presented higher resistance to pressure treatment compared to Salmonella spp. Initial temperatures (8 and 15°C) had no significant influence on Salmonella log reductions. Log reduction of pathogens increased but not significantly with increase of temperature. AA did not show any significant antimicrobial activity. Viable counts were about 0.2-0.4logCFU/g less in presence of 0.1% AA. These data validate that HHP can be used as an effective method for decontamination of cantaloupe puree. Published by Elsevier B.V.

  5. Fatty Acid Profiling of Lipid A Isolated from Indigenous salmonella typhi strain by gas chromatography mass spectrometry

    Energy Technology Data Exchange (ETDEWEB)

    Jabbar, A.; Ali, A.; Tawab, A.; Haque, A.; Iqbal, M. [National Inst. for Biotechnology and Genetic Engineering, Faisalabad (Pakistan)

    2014-02-15

    Typhoid, caused by Salmonella enterica serovar Typhi (S. Typhi), is a major health problem worldwide especially in developing countries. Lipopolysaccharides are one of the main virulence factors of S. Typhi. Hydrophobic lipid A anchors the lipopolysaccharides into the bacterial outer membrane and also serves as the epicenter of endotoxicity, which is linked to the presence of several fatty acid chains. Fatty acid profiling is, therefore, very important to understand the endotoxicity of these pathogenic bacteria. To profile lipid A with respect to its fatty acid constituents, a S. Typhi was isolated from blood culture of a typhoid patient from the Faisalabad region of Pakistan. After its complete identification using biochemical and molecular techniques, this bacterium was cultivated in a fermentor. The cell pellet obtained was subjected to hot phenol process to extract and purify lipopolysaccharides. Acid hydrolysis of the lipopolysaccharides yielded lipid A, which was subjected to analyses using GC-MS after derivatization into their fatty acid methyl esters. The fatty acid methyl esters were identified on the basis of their retention times, compared with standards as well as characteristic mass fragmentation patterns of their respective mass spectra. This fatty acid profiling revealed the occurrence of dodecanoic acid (C12:0), tetradecanoic acid (C14:0), 3-hydroxy tetradecanoic acid (3-OH C14:0) and hexadecanoic acid (C16:0) in the lipid A component of S. Typhi strain with the relative percentage abundances 8.5%, 12.5%, 55.9% and 23.1%, respectively. (author)

  6. Fatty Acid Profiling of Lipid A Isolated from Indigenous salmonella typhi strain by gas chromatography mass spectrometry

    International Nuclear Information System (INIS)

    Jabbar, A.; Ali, A.; Tawab, A.; Haque, A.; Iqbal, M.

    2014-01-01

    Typhoid, caused by Salmonella enterica serovar Typhi (S. Typhi), is a major health problem worldwide especially in developing countries. Lipopolysaccharides are one of the main virulence factors of S. Typhi. Hydrophobic lipid A anchors the lipopolysaccharides into the bacterial outer membrane and also serves as the epicenter of endotoxicity, which is linked to the presence of several fatty acid chains. Fatty acid profiling is, therefore, very important to understand the endotoxicity of these pathogenic bacteria. To profile lipid A with respect to its fatty acid constituents, a S. Typhi was isolated from blood culture of a typhoid patient from the Faisalabad region of Pakistan. After its complete identification using biochemical and molecular techniques, this bacterium was cultivated in a fermentor. The cell pellet obtained was subjected to hot phenol process to extract and purify lipopolysaccharides. Acid hydrolysis of the lipopolysaccharides yielded lipid A, which was subjected to analyses using GC-MS after derivatization into their fatty acid methyl esters. The fatty acid methyl esters were identified on the basis of their retention times, compared with standards as well as characteristic mass fragmentation patterns of their respective mass spectra. This fatty acid profiling revealed the occurrence of dodecanoic acid (C12:0), tetradecanoic acid (C14:0), 3-hydroxy tetradecanoic acid (3-OH C14:0) and hexadecanoic acid (C16:0) in the lipid A component of S. Typhi strain with the relative percentage abundances 8.5%, 12.5%, 55.9% and 23.1%, respectively. (author)

  7. Thermal tolerance of acid-adapted and unadapted Salmonella, Escherichia coli O157:H7, and Listeria monocytogenes in cantaloupe juice and watermelon juice.

    Science.gov (United States)

    Sharma, M; Adler, B B; Harrison, M D; Beuchat, L R

    2005-01-01

    A study was performed to determine D values of acid-adapted and unadapted cells of Salmonella, Escherichia coli O157:H7, and Listeria monocytogenes in cantaloupe juice and watermelon juice. Salmonella enterica serotype Poona, S. enterica serotype Saphra, two strains of E. coli O157:H7, and two strains of L. monocytogenes were grown in tryptic soy broth (TSB) and TSB supplemented with 1% glucose for 24 h at 37 degrees C. Decimal reduction times (D values) of cells suspended in unpasteurized cantaloupe juice and watermelon juice were determined. Acid-adapted cells of Salmonella and E. coli O157:H7, but not L. monocytogenes, had increased thermal tolerance compared with cells that were not acid-adapted. There was no correlation between soluble solids content of the two types of juice and thermal resistance. Growth of Salmonella and E. coli O157:H7 in cantaloupe juice, watermelon juice, or other acidic milieu, either in preharvest or postharvest environments, may result in cross protection to heat. The pasteurization conditions necessary to achieve elimination of pathogens from these juices would consequently have to be more severe if cells are habituated to acidic environments. Insights from this study provide guidance to developing pasteurization processes to eliminate Salmonella, E. coli O157:H7, and L. monocytogenes in cantaloupe juice and watermelon juice.

  8. Development of Chemically Defined Media to Express Trp-Analog-Labeled Proteins in a Lactococcus lactis Trp Auxotroph.

    Science.gov (United States)

    Shao, Jinfeng; Marcondes, Marcelo F M; Oliveira, Vitor; Broos, Jaap

    2016-01-01

    Chemically defined media for growth of Lactococcus lactis strains contain about 50 components, making them laborious and expensive growth media. However, they are crucial for metabolism studies as well as for expression of heterologous proteins labeled with unnatural amino acids. In particular, the L. lactis Trp auxotroph PA1002, overexpressing the tryptophanyl tRNA synthetase enzyme of L. lactis, is very suitable for the biosynthetic incorporation of Trp analogs in proteins because of its most relaxed substrate specificity reported towards Trp analogs. Here we present two much simpler defined media for L. lactis, which consist of only 24 or 31 components, respectively, and with which the L. lactis Trp auxotroph shows similar growth characteristics as with a 50-component chemically defined medium. Importantly, the expression levels of two recombinant proteins used for evaluation were up to 2-3 times higher in these new media than in the 50-component medium, without affecting the Trp analog incorporation efficiency. Taken together, the simplest chemically defined media reported so far for L. lactis are presented. Since L. lactis also shows auxotrophy for Arg, His, Ile, Leu Val, and Met, our simplified media may also be useful for the biosynthetic incorporation of analogs of these five amino acids. © 2016 The Author(s) Published by S. Karger AG, Basel.

  9. Molecular characterization and expression study of a histidine auxotrophic mutant (his1-) of Nicotiana plumbaginifolia.

    Science.gov (United States)

    El Malki, F; Jacobs, M

    2001-01-01

    The histidine auxotroph mutant his 1(-) isolated from Nicotiana plumbaginifolia haploid protoplasts was first characterized to be deficient for the enzyme histidinol phosphate aminotransferase that is responsible for one of the last steps of histidine biosynthesis. Expression of the mutated gene at the RNA level was assessed by northern analysis of various tissues. Transcriptional activity was unimpaired by the mutation and, in contrast, a higher level of expression was obtained when compared to the wild-type. The cDNA sequence encoding the mutated gene was isolated by RT-PCR and compared to the wild-type gene. A single point mutation corresponding to the substitution of a G nucleotide by A was identified at position 1212 starting from the translation site. The alignment of the deduced amino acid sequences from the mutated and wild-type gene showed that this mutation resulted in the substitution of an Arg by a His residue at position 381. This Arg residue is a conserved amino acid for histidinol phosphate aminotransferase of many species. These results indicate that the identified mutation results in an altered histidinol phosphate aminotransferase enzyme that is unable to convert the substrate imidazole acetol phosphate to histidinol phosphate and thereby leads to the blockage of histidine biosynthesis. Possible consequences of this blockage on the expression of other amino acid biosynthesis genes were evaluated by analysing the expression of the dhdps gene encoding dihydrodipicolinate synthase, the first key enzyme of the lysine pathway.

  10. Antimicrobial activity optimization of nisin, ascorbic acid and ethylenediamine tetraacetic acid disodium salt (EDTA against Salmonella Enteritidis ATCC 13076 using response surface methodology

    Directory of Open Access Journals (Sweden)

    Nongpanga Sangcharoen

    2017-10-01

    Full Text Available Nisin is a commercial bacteriocin produced by Lactococcus lactis subsp. lactis and widely used as a natural preservative in the food industry. However, while nisin alone cannot inhibit the growth of Gram-negative bacteria, it can in combination with a chelating agent or organic acid. This study combined nisin with some chelating agents, weak organic acids and their salts to inhibit Salmonella Enteritidis ATCC 13076. The combinations of nisin (2000 parts per million; ppm and ascorbic acid (2000 ppm or ethylenediamine tetraacetic acid disodium salt (EDTA; 7400 ppm showed significant inhibitory effects on the target strain. Due to regulatory limits, the second part of the study reduced the concentrations of nisin, ascorbic acid and EDTA to 500 ppm, 2000 ppm and 250 ppm, respectively. The mixture of nisin, ascorbic acid and EDTA showed the highest inhibitory effect with a reduction number of 3.41 log colony forming units (p < 0.05. To minimize the growth of S. Enteritidis ATCC 13076, central composite design and response surface methodology were applied to investigate the combined effect of nisin (0–500 ppm, ascorbic acid (0–2000 ppm, and EDTA (0–250 ppm on the target strain growth. Among the three factors, nisin had a higher antimicrobial effect than ascorbic acid or EDTA, while an increase in nisin resulted in a decrease in S. Enteritidis ATCC 13076 growth. The optimum concentration was 500 ppm nisin with 1515 ppm ascorbic acid and 250 ppm EDTA. Under these conditions, the growth of S. Enteritidis ATCC 13076 predicted by the model was 24.99%. Keywords: Antimicrobial activity, Ascorbic acid, Ethylenediamine tetraacetic acid disodium salt (EDTA, Nisin, Salmonella enteritidis

  11. Acid and low temperature treatments on Salmonella Enteritidis inoculated in pork and its subsequent survival in simulated gastric fluid

    Directory of Open Access Journals (Sweden)

    Simone Quintão Silva

    2016-03-01

    Full Text Available ABSTRACT: The objective of this study was to evaluate the acid resistance of Salmonella enterica serovar Enteritidis (S. Enteritidis in stored pork and in simulated gastric fluid (SGF. A culture of S. Enteritidis was subjected to acid treatment prior to inoculation into pork, stored under refrigeration at frozen temperatures and exposed to SGF. The S. Enteritidis CCS3 and ATCC 13076 strains previously subjected to acid treatment (at pH 4.0-5.0 were inoculated in pork and stored at 4°C and -18°C. Storage at 4ºC did not affect the populations of both S. Enteritidis strains. After 84 days at -18°C, the mean population of both CCS3 and ATCC strains were reduced by 0.8 and 1.5 log cycles, respectively. Prior acid treatment did not enhance the survival of both strains at low temperatures. After acid treatment and low temperature storage, S. Enteritidis ATCC 13076 lost culturability after being exposed to SGF for 10 minutes. In contrast, S. Enteritidis CCS3 was tolerant until three hours of SGF exposure. S. Enteritidis CCS3 submitted to pH 4.0 was more tolerant to SGF exposure than when submitted to pH 4.5, 5.0 and without acid treatment. Therefore, this study indicates that exposure to an acidic and cold environment during processing enhanced the ability of S. Enteritidis to survive in the gastric environment of the human stomach, possibly increasing the risk of a Salmonella infection after consumption of pork.

  12. Nalidixic acid-resistant Salmonella enteric serotype typhi infection presenting with sub-intestinal obstruction and mesenteric adenitis

    International Nuclear Information System (INIS)

    Al-Khuwaitir, Tarig S.; Al-Zuhair, Amin A.; Al-Ghamdi, Ali G.; Khan, A.

    2008-01-01

    Nalidixic acid-resistant Salmonella typhi NARST infections increase minimal inhibitory concentrations of fluoroquinolones, due to chromosomal mutations in the gene encoding DNA gyrase, and can lead to a delayed treatment response. This in turn alters the course of the disease allowing for a protracted period of illness and the occurrence of complications. In this case report, we present a patient from the Indian sub-continent, who was diagnosed with NARST complicated by sub-intestinal obstruction, her diagnosis, treatment and subsequent recovery. (author)

  13. Tomato type and post-treatment water rinse affect efficacy of acid washes against Salmonella enterica inoculated on stem scars of tomatoes and product quality.

    Science.gov (United States)

    Fan, Xuetong; Gurtler, Joshua B; Sokorai, Kimberly J B

    2018-09-02

    A study was conducted to evaluate the effects of post-treatment rinsing with water on the inactivation efficacy of acid treatments against Salmonella inoculated onto stem scar areas of two types of tomatoes. In addition, impact on fruit quality was investigated during 21 days post-treatment storage at 10 °C. A four-strain cocktail of Salmonella enterica (S. Montevideo, S. Newport, S. Saintpaul, and S. Typhimurium) was inoculated onto stem scar areas of grape and large round tomatoes. The inoculated fruits were then treated for 2 min with the following solutions: water, 2% lactic acid +2% acetic acid +2% levulinic acid, 1.7% lactic acid +1.7% acetic acid +1.7% levulinic acid, and 3% lactic acid +3% acetic acid. After treatments, half of the fruits were rinsed with water while another half were not rinsed. Non-inoculated grape tomatoes for quality analysis were treated with the same solutions with and without subsequent water rinse. Results demonstrated that the acid combinations reduced populations of Salmonella enterica on the stem scar area of grape tomatoes by 1.52-1.90 log CFU/fruit, compared with the non-treated control while water wash and rinse removed the bacterium by only 0.23-0.30 log CFU/fruit. On the stem scar of large round tomatoes, the same acid treatments achieved 3.54 log CFU/fruit reduction of the pathogen. The varying response to the acid washes between grape and large round tomatoes seems to be related to the differences in surface characteristics of stem scar areas observed with SEM. Rinsing with water after acid combination treatments did not significantly affect the efficacy of the treatments in either grape or large round tomatoes. Acidic off-odor was detected on fruits treated with acid combination without water rinse 1 day after treatment while water rinse eliminated the off-odor. The acid treatments with and without water rinse did not consistently affect appearance, color, firmness, or lycopene or ascorbic acid contents of

  14. Effects of irradiation and fumaric acid treatment on the inactivation of Listeria monocytogenes and Salmonella typhimurium inoculated on sliced ham

    Science.gov (United States)

    Song, Hyeon-Jeong; Lee, Ji-Hye; Song, Kyung Bin

    2011-11-01

    To examine the effects of fumaric acid and electron beam irradiation on the inactivation of foodborne pathogens in ready-to-eat meat products, sliced ham was inoculated with Listeria monocytogenes and Salmonella typhimurium. The inoculated ham slices were treated with 0.5% fumaric acid or electron beam irradiation at 2 kGy. Fumaric acid treatment reduced the populations of L. monocytogenes and S. typhimurium by approximately 1 log CFU/g compared to control populations. In contrast, electron beam irradiation decreased the populations of S. typhimurium and L. monocytogenes by 3.78 and 2.42 log CFU/g, respectively. These results suggest that electron beam irradiation is a better and appropriate technique for improving the microbial safety of sliced ham.

  15. Effect of chlorate, molybdate, and shikimic acid on Salmonella enterica serovar Typhimurium in aerobic and anaerobic cultures.

    Science.gov (United States)

    Oliver, Christy E; Beier, Ross C; Hume, Michael E; Horrocks, Shane M; Casey, Thomas A; Caton, Joel S; Nisbet, David J; Smith, David J; Krueger, Nathan A; Anderson, Robin C

    2010-04-01

    Experiments were conducted to determine factors that affect sensitivity of Salmonella enterica serovar Typhimurium to sodium chlorate (5mM). In our first experiment, cultures grown without chlorate grew more rapidly than those with chlorate. An extended lag before logarithmic growth was observed in anaerobic but not aerobic cultures containing chlorate. Chlorate inhibition of growth during aerobic culture began later than that observed in anaerobic cultures but persisted once inhibition was apparent. Conversely, anaerobic cultures appeared to adapt to chlorate after approximately 10h of incubation, exhibiting rapid compensatory growth. In anaerobic chlorate-containing cultures, 20% of total viable counts were resistant to chlorate by 6h and had propagated to 100% resistance (>10(9)CFU mL(-1)) by 24h. In the aerobic chlorate-containing cultures, 12.9% of colonies had detectable resistance to chlorate by 6h, but only 1% retained detectable resistance at 24h, likely because these cultures had opportunity to respire on oxygen and were thus not enriched via the selective pressure of chlorate. In another study, treatment with shikimic acid (0.34 mM), molybdate (1mM) or their combination had little effect on aerobic or anaerobic growth of Salmonella in the absence of added chlorate. As observed in our earlier study, chlorate resistance was not detected in any cultures without added chlorate. Chlorate resistant Salmonella were recovered at equivalent numbers regardless of treatment after 8h of aerobic or anaerobic culture with added chlorate; however, by 24h incubation chlorate sensitivity was completely restored to aerobic but not anaerobic cultures treated with shikimic acid or molybdate but not their combination. Results indicate that anaerobic adaptation of S. Typhimurium to sodium chlorate during pure culture is likely due to the selective propagation of low numbers of cells exhibiting spontaneous resistance to chlorate and this resistance is not reversible by

  16. TolC is important for bacterial survival and oxidative stress response in Salmonella enterica serovar Choleraesuis in an acidic environment.

    Science.gov (United States)

    Lee, Jen-Jie; Wu, Ying-Chen; Kuo, Chih-Jung; Hsuan, Shih-Ling; Chen, Ter-Hsin

    2016-09-25

    The outer membrane protein TolC, which is one of the key components of several multidrug efflux pumps, is thought to be involved in various independent systems in Enterobacteriaceae. Since the acidic environment of the stomach is an important protection barrier against foodborne pathogen infections in hosts, we evaluated whether TolC played a role in the acid tolerance of Salmonella enterica serovar Choleraesuis. Comparison of the acid tolerance of the tolC mutant and the parental wild-type strain showed that the absence of TolC limits the ability of Salmonella to sustain life under extreme acidic conditions. Additionally, the mutant exhibited morphological changes during growth in an acidic medium, leading to the conflicting results of cell viability measured by spectrophotometry and colony-forming unit counting. Reverse-transcriptional-PCR analysis indicated that acid-related molecules, apparatus, or enzymes and oxidation-induced factors were significantly affected by the acidic environment in the null-tolC mutant. The elongated cellular morphology was restored by adding antioxidants to the culture medium. Furthermore, we found that increased cellular antioxidative activity provides an overlapping protection against acid killing, demonstrating the complexity of the bacterial acid stress response. Our findings reinforce the multifunctional characteristics of TolC in acid tolerance or oxidative stress resistance and support the correlative protection mechanism between oxygen- and acid-mediated stress responses in Salmonella enterica serovar Choleraesuis. Copyright © 2016 Elsevier B.V. All rights reserved.

  17. Salmonella O48 Serum Resistance is Connected with the Elongation of the Lipopolysaccharide O-Antigen Containing Sialic Acid

    Directory of Open Access Journals (Sweden)

    Aleksandra Pawlak

    2017-09-01

    Full Text Available Complement is one of the most important parts of the innate immune system. Some bacteria can gain resistance against the bactericidal action of complement by decorating their outer cell surface with lipopolysaccharides (LPSs containing a very long O-antigen or with specific outer membrane proteins. Additionally, the presence of sialic acid in the LPS molecules can provide a level of protection for bacteria, likening them to human cells, a phenomenon known as molecular mimicry. Salmonella O48, which contains sialic acid in the O-antigen, is the major cause of reptile-associated salmonellosis, a worldwide public health problem. In this study, we tested the effect of prolonged exposure to human serum on strains from Salmonella serogroup O48, specifically on the O-antigen length. After multiple passages in serum, three out of four tested strains became resistant to serum action. The gas-liquid chromatography/tandem mass spectrometry analysis showed that, for most of the strains, the average length of the LPS O-antigen increased. Thus, we have discovered a link between the resistance of bacterial cells to serum and the elongation of the LPS O-antigen.

  18. Combination of peracetic acid and ultrasound reduces Salmonella Typhimurium on fresh lettuce (Lactuca sativa L. var. crispa).

    Science.gov (United States)

    Silveira, Luiza Oliveira; do Rosário, Denes Kaic Alves; Giori, Ana Carolina Garcia; Oliveira, Syllas Borburema Silva; da Silva Mutz, Yhan; Marques, Clara Suprani; Coelho, Jussara Moreira; Bernardes, Patrícia Campos

    2018-04-01

    Salmonella outbreaks related to fruits and vegetables have been reported being lettuce one of the most contaminated. Peracetic acid (PA) at 50 mg/L, sodium dichloroisocyanurate (SD) at 100 mg/L, and the combination of SD at 100 mg/L and babaçu coconut ( Attalea speciosa ) oil detergent at 100 mg/L were applied to fresh lettuce. Natural contaminant microbiota, physicochemical characteristics, and sensory attributes were evaluated. PA and SD reduced mesophilic aerobic counts by 2.1 and 1.5 log cfu/g, respectively. The most efficient treatment in reducing natural microbiota (i.e., PA) was applied alone and in combination with ultrasound (US). It reduced Salmonella enterica Typhimurium counts to undetectable levels (< 1 log cfu/g). US further reduced S. Typhimurium counts by 0.6 log cfu/g in relation to PA, treatment which lessened the pH but increased the titratable acidity of lettuce, but did not cause total color difference. Therefore, the combination of PA and US holds a potential industrial application for sanitization purposes.

  19. Expression of hilA in response to mild acid stress in Salmonella enterica is serovar and strain dependent.

    Science.gov (United States)

    González-Gil, Francisco; Le Bolloch, Alexandre; Pendleton, Sean; Zhang, Nan; Wallis, Audra; Hanning, Irene

    2012-05-01

    Salmonella enterica is the leading cause of foodborne illness with poultry and poultry products being primary sources of infection. The 2 most common S. enterica serovars associated with human infection are Typhimurium and Enteritidis. However, Kentucky and Heidelburg and the 2 most prevalent serovars isolated from poultry environments. Given the prevalence of other serovars in poultry products and environments, research is needed to understand virulence modulation in response to stress in serovars other than Typhimurium and Enteritidis. Thus, the objective of this research was to compare hilA gene expression (a master regulator of the virulence pathogenicity island) in response to acid stress among different strains and serovars of Salmonella. A total of 11 serovars consisting of 15 strains of S. enterica were utilized for these experiments. Cultures were suspended in tryptic soy broth (TSB) adjusted to pH 7.2, 6.2, or 5.5 with HCl or acetic acid. Total RNA was extracted from cultures at specific time points (0, 2, 4, and 24 h). Gene expression of hilA was measured with quantitative reverse transcriptase real time PCR (qRT-PCR). Growth and pH were measured throughout the 24 h time frame. Regulation of hilA in response to acid stress varied by serovar and strain and type of acid. The results of these experiments indicate that hilA regulation may have some impact on virulence and colonization of S. enterica. However, these results warrant further research to more fully understand the significance of hilA regulation in response to mild acid stress in S. enterica. © 2012 Institute of Food Technologists®

  20. UV-irradiation potentiates the antimutagenicity of p-aminobenzoic and p-aminosalicylic acids in Salmonella typhimurium

    International Nuclear Information System (INIS)

    Gichner, T.; Baburek, I.; Veleminsky, J.; Kappas, A.

    1991-01-01

    UV-irradiation (254 nm, 10 or 20 J/cm 2 ) of p-aminobenzoic acid (PABA) and p-aminosalicylic acid (NaPAS) potentiated their antimuta-genicity towards N-methyl-N'-nitro-N-nitrosoguanide metagenesis in Salmonella typhimurium. Their inhibitory action towards the formation of mutagen N-methyl-N-mitrosourea from the nitrosation mixture of N-methylurea and nitrite was also increased by UV-irradiation. In contrast, UV-irradiated PABA exhibited no inhibitory effects towards the mutagenicity of sodium azide or 3-azidoglycerol. Neither PABA nor NaPAS not their UV-irradiation products were themselves mutagenic in the Ames assay. 13 refs.; 5 tabs

  1. Nalidixic Acid-Resistant Salmonella enterica Serotype Typhi Presenting as a Primary Psoas Abscess: Case Report and Review of the Literature

    Science.gov (United States)

    Shakespeare, William A.; Davie, Daniel; Tonnerre, Claude; Rubin, Michael A.; Strong, Michael; Petti, Cathy A.

    2005-01-01

    We report an unusual case of Salmonella enterica serotype Typhi presenting as a primary psoas abscess. The isolate tested susceptible to ciprofloxacin but resistant to nalidixic acid in vitro, a pattern associated with fluoroquinolone therapeutic failures. We review the literature for serovar Typhi psoas abscess in the absence of bacteremia and discuss the importance of identifying isolates with reduced susceptibility to fluoroquinolones. PMID:15695728

  2. Nalidixic acid-resistant Salmonella enterica serotype Typhi presenting as a primary psoas abscess: case report and review of the literature.

    Science.gov (United States)

    Shakespeare, William A; Davie, Daniel; Tonnerre, Claude; Rubin, Michael A; Strong, Michael; Petti, Cathy A

    2005-02-01

    We report an unusual case of Salmonella enterica serotype Typhi presenting as a primary psoas abscess. The isolate tested susceptible to ciprofloxacin but resistant to nalidixic acid in vitro, a pattern associated with fluoroquinolone therapeutic failures. We review the literature for serovar Typhi psoas abscess in the absence of bacteremia and discuss the importance of identifying isolates with reduced susceptibility to fluoroquinolones.

  3. Change in attachment of Salmonella Typhimurium, Yersinia enterocolitica, and Listeria monocytogenes to pork skin and muscle after hot water and lactic acid decontamination

    DEFF Research Database (Denmark)

    Morild, Rikke K.; Olsen, John E.; Aabo, Søren

    2011-01-01

    The attachment of Salmonella enterica subsp. enterica serovar Typhimurium, Yersinia enterocolitica, and Listeria monocytogenes to pig skin and muscle tissue decontaminated with 80°C water or 55°C, 1% lactic acid for 5 and 15s was investigated. Attachment properties differed between skin and muscle...

  4. Controlling Salmonella infection in weanling pigs through water delivery of direct-fed microbials or organic acids: Part II. Effects on intestinal histology and active nutrient transport

    Science.gov (United States)

    The objective of this study was to evaluate the effects of water-delivered direct-fed microbials (DFM) or organic acids on intestinal morphology and active nutrient absorption in weanling pigs following deliberate Salmonella infection. Pigs (n = 88) were weaned at 19 ± 2 d of age and assigned to one...

  5. Effects of irradiation and fumaric acid treatment on the inactivation of Listeria monocytogenes and Salmonella typhimurium inoculated on sliced ham

    International Nuclear Information System (INIS)

    Song, Hyeon-Jeong; Lee, Ji-Hye; Song, Kyung Bin

    2011-01-01

    To examine the effects of fumaric acid and electron beam irradiation on the inactivation of foodborne pathogens in ready-to-eat meat products, sliced ham was inoculated with Listeria monocytogenes and Salmonella typhimurium. The inoculated ham slices were treated with 0.5% fumaric acid or electron beam irradiation at 2 kGy. Fumaric acid treatment reduced the populations of L. monocytogenes and S. typhimurium by approximately 1 log CFU/g compared to control populations. In contrast, electron beam irradiation decreased the populations of S. typhimurium and L. monocytogenes by 3.78 and 2.42 log CFU/g, respectively. These results suggest that electron beam irradiation is a better and appropriate technique for improving the microbial safety of sliced ham. - Highlights: → We compare irradiation and fumaric acid treatment on the inactivation of pathogens. → We examine changes in the populations of L. monocytogenes and S. typhimurium. → Irradiation at 2 kGy is more effective in sliced ham than fumaric acid treatment. → Low-dose irradiation can improve the microbial safety of sliced ham during storage.

  6. Effects of irradiation and fumaric acid treatment on the inactivation of Listeria monocytogenes and Salmonella typhimurium inoculated on sliced ham

    Energy Technology Data Exchange (ETDEWEB)

    Song, Hyeon-Jeong; Lee, Ji-Hye [Department of Food Science and Technology, Chungnam National University, Daejeon 305-764 (Korea, Republic of); Song, Kyung Bin, E-mail: kbsong@cnu.ac.kr [Department of Food Science and Technology, Chungnam National University, Daejeon 305-764 (Korea, Republic of)

    2011-11-15

    To examine the effects of fumaric acid and electron beam irradiation on the inactivation of foodborne pathogens in ready-to-eat meat products, sliced ham was inoculated with Listeria monocytogenes and Salmonella typhimurium. The inoculated ham slices were treated with 0.5% fumaric acid or electron beam irradiation at 2 kGy. Fumaric acid treatment reduced the populations of L. monocytogenes and S. typhimurium by approximately 1 log CFU/g compared to control populations. In contrast, electron beam irradiation decreased the populations of S. typhimurium and L. monocytogenes by 3.78 and 2.42 log CFU/g, respectively. These results suggest that electron beam irradiation is a better and appropriate technique for improving the microbial safety of sliced ham. - Highlights: > We compare irradiation and fumaric acid treatment on the inactivation of pathogens. > We examine changes in the populations of L. monocytogenes and S. typhimurium. > Irradiation at 2 kGy is more effective in sliced ham than fumaric acid treatment. > Low-dose irradiation can improve the microbial safety of sliced ham during storage.

  7. Enhanced intracellular delivery and antibacterial efficacy of enrofloxacin-loaded docosanoic acid solid lipid nanoparticles against intracellular Salmonella.

    Science.gov (United States)

    Xie, Shuyu; Yang, Fei; Tao, Yanfei; Chen, Dongmei; Qu, Wei; Huang, Lingli; Liu, Zhenli; Pan, Yuanhu; Yuan, Zonghui

    2017-01-23

    Enrofloxacin-loaded docosanoic acid solid lipid nanoparticles (SLNs) with different physicochemical properties were developed to enhance activity against intracellular Salmonella. Their cellular uptake, intracellular elimination and antibacterial activity were studied in RAW 264.7 cells. During the experimental period, SLN-encapsulated enrofloxacin accumulated in the cells approximately 27.06-37.71 times more efficiently than free drugs at the same extracellular concentration. After incubation for 0.5 h, the intracellular enrofloxacin was enhanced from 0.336 to 1.147 μg/mg of protein as the sizes of nanoparticles were increased from 150 to 605 nm, and from 0.960 to 1.147 μg/mg of protein when the charge was improved from -8.1 to -24.9 mv. The cellular uptake was more significantly influenced by the size than it was by the charge, and was not affected by whether the charge was positive or negative. The elimination of optimal SLN-encapsulated enrofloxacin from the cells was significantly slower than that of free enrofloxacin after removing extracellular drug. The inhibition effect against intracellular Salmonella CVCC541 of 0.24 and 0.06 μg/mL encapsulated enrofloxacin was stronger than 0.6 μg/mL free drug after all of the incubation periods and at 48 h, respectively. Docosanoic acid SLNs are thus considered as a promising carrier for intracellular bacterial treatment.

  8. Biofilm formation by Staphylococcus aureus and Salmonella spp. under mono and dual-species conditions and their sensitivity to cetrimonium bromide, peracetic acid and sodium hypochlorite.

    Science.gov (United States)

    Iñiguez-Moreno, Maricarmen; Gutiérrez-Lomelí, Melesio; Guerrero-Medina, Pedro Javier; Avila-Novoa, María Guadalupe

    The aim of this study was evaluated the biofilm formation by Staphylococcus aureus 4E and Salmonella spp. under mono and dual-species biofilms, onto stainless steel 316 (SS) and polypropylene B (PP), and their sensitivity to cetrimonium bromide, peracetic acid and sodium hypochlorite. The biofilms were developed by immersion of the surfaces in TSB by 10 d at 37°C. The results showed that in monospecies biofilms the type of surface not affected the cellular density (p>0.05). However, in dual-species biofilms on PP the adhesion of Salmonella spp. was favored, 7.61±0.13Log 10 CFU/cm 2 , compared with monospecies biofilms onto the same surface, 5.91±0.44Log 10 CFU/cm 2 (pdisinfection treatments; and the most effective disinfectant was peracetic acid (3500ppm), reducing by more than 5Log 10 CFU/cm 2 , while the least effective was cetrimonium bromide. In addition, S. aureus 4E and Salmonella spp. were more resistant to the disinfectants in mono than in dual-species biofilms (p<0.05). Therefore, the interspecies interactions between S. aureus 4E and Salmonella spp. had a negative effect on the antimicrobial resistance of each microorganism, compared with the monospecies biofilms. Copyright © 2017 Sociedade Brasileira de Microbiologia. Published by Elsevier Editora Ltda. All rights reserved.

  9. Biofilm formation by Staphylococcus aureus and Salmonella spp. under mono and dual-species conditions and their sensitivity to cetrimonium bromide, peracetic acid and sodium hypochlorite

    Directory of Open Access Journals (Sweden)

    Maricarmen Iñiguez-Moreno

    Full Text Available Abstract The aim of this study was evaluated the biofilm formation by Staphylococcus aureus 4E and Salmonella spp. under mono and dual-species biofilms, onto stainless steel 316 (SS and polypropylene B (PP, and their sensitivity to cetrimonium bromide, peracetic acid and sodium hypochlorite. The biofilms were developed by immersion of the surfaces in TSB by 10 d at 37 °C. The results showed that in monospecies biofilms the type of surface not affected the cellular density (p > 0.05. However, in dual-species biofilms on PP the adhesion of Salmonella spp. was favored, 7.61 ± 0.13 Log10 CFU/cm2, compared with monospecies biofilms onto the same surface, 5.91 ± 0.44 Log10 CFU/cm2 (p < 0.05. The mono and dual-species biofilms were subjected to disinfection treatments; and the most effective disinfectant was peracetic acid (3500 ppm, reducing by more than 5 Log10 CFU/cm2, while the least effective was cetrimonium bromide. In addition, S. aureus 4E and Salmonella spp. were more resistant to the disinfectants in mono than in dual-species biofilms (p < 0.05. Therefore, the interspecies interactions between S. aureus 4E and Salmonella spp. had a negative effect on the antimicrobial resistance of each microorganism, compared with the monospecies biofilms.

  10. Salmonella osteomyelitis

    OpenAIRE

    Somsri Wiwanitkit; Viroj Wiwanitkit

    2016-01-01

    Salmonella infection can cause four predominant clinical syndromes: enteric fever, acute gastroenteritis, bacteraemia with or without metastatic infection, and the asymptomatic carrier state. Salmonella as an aetiological agent in osteomyelitis is essentially rare and salmonella osteomyelitis in itself is predominantly seen in patients with haemoglobinopathies such as sickle cell disease or thalassemia. There are very few cases reported in the literature in which salmonella osteomyelitis is s...

  11. Radiation-induced mutagenicity and lethality in Salmonella typhimurium

    International Nuclear Information System (INIS)

    Isildar, M.; Bakale, G.

    1983-01-01

    The mutagenic and lethal effects of ionizing radiation on histidine-deficient auxotrophs of Salmonella typhimurium were studied to improve the understanding of radiation damage to DNA. The auxotrophs were divided into two groups - one which is sensitive to base-pair substitutions and another sensitive to frameshifts. These groups were composed of parent-daughter pairs in which the chemical mutagenicity enhancing plasmid, pKM101, is absent in the parent strain and present in the daughter. Co-60 #betta#-radiation and 250 kV x-rays were used to irradiate the bacteria. Irradiation of the frameshift - sensitive strains which carry the pKm101 plasmid doubled the absolute number of induced revertants whereas irradiation of the base-pair substitution sensitive strain which also carries the pKm101 plasmid produced nearly no change in the number of induced revertants. A nearly negligible effect on the mutation rate was observed for all parent strains

  12. pH-, Lactic acid-, and non-lactic acid-dependent activities of probiotic Lactobacilli against Salmonella enterica Serovar Typhimurium.

    Science.gov (United States)

    Fayol-Messaoudi, Domitille; Berger, Cédric N; Coconnier-Polter, Marie-Hélène; Liévin-Le Moal, Vanessa; Servin, Alain L

    2005-10-01

    The mechanism(s) underlying the antibacterial activity of probiotic Lactobacillus strains appears to be multifactorial and includes lowering of the pH and the production of lactic acid and of antibacterial compounds, including bacteriocins and nonbacteriocin, non-lactic acid molecules. Addition of Dulbecco's modified Eagle's minimum essential medium to the incubating medium delays the killing activity of lactic acid. We found that the probiotic strains Lactobacillus johnsonii La1, Lactobacillus rhamnosus GG, Lactobacillus casei Shirota YIT9029, L. casei DN-114 001, and L. rhamnosus GR1 induced a dramatic decrease in the viability of Salmonella enterica serovar Typhimurium SL1344 mainly attributable to non-lactic acid molecule(s) present in the cell-free culture supernatant (CFCS). These molecules were more active against serovar Typhimurium SL1344 in the exponential growth phase than in the stationary growth phase. We also showed that the production of the non-lactic acid substance(s) responsible for the killing activity was dependent on growth temperature and that both unstable and stable substances with killing activity were present in the CFCSs. We found that the complete inhibition of serovar Typhimurium SL1344 growth results from a pH-lowering effect.

  13. Salmonella: Salmonellosis

    DEFF Research Database (Denmark)

    Löfström, Charlotta; Hansen, Trine; Maurischat, Sven

    2015-01-01

    Salmonella remains one of the most important zoonotic pathogenic bacteria and is the causative agents of salmonellosis. The aim of this article is to give an overview of Salmonella and salmonellosis, starting by describing the characteristics of the microorganism Salmonella, including biochemical...

  14. MICROENCAPSULATION OF INDIGENOUS POULTRY LACTIC ACID BACTERIA PROBIOTIC ON THE COMPETITIVE EXCLUSION AGAINST Salmonella enteritidis AND Escherichia coli IN VITRO

    Directory of Open Access Journals (Sweden)

    Monica Sonia Indri Pradipta

    2017-05-01

    Full Text Available This study was conducted to investigate the effect of microencapsulation of lactic acid bacteria (LAB probiotic isolated from chickens’ gastrointestinal tract on Salmonella enterica serotype enteritidis ATCC 13076 and Escherichia coli EPEC. Probiotic of LAB used were Streptococcus thermophilus strain Kp-2, Lactobacillus murinus strain Ar-3, and Pediococcus acidilactici strain Kd-6. Microencapsulation were conducted by spray drying with inlet/outlet temperatures of 160/80°C using maltodextrin and skim milk powder (20% w/v as coating materials. Competitive exclusion test was conducted in vitro using well diffusion method. Variable measured in this study was the clear zone observed. The data of clear zone among treatments were analyzed using analysis of variance (ANOVA one way followed by Duncan multiple range test (DMRT; except the data of clear zone resulted by probiotic before and after microencapsulation that was analyzed using t-test. The result showed that the ability of each strain against pathogen was decreased after being encapsulated. S. thermophilus before and after microencapsulation had the same antagonistic ability against E. coli and S. enteritidis (P>0.05. Microencapsulation process with spray drying method decreased antagonistic ability of probiotic against pathogenic bacteria both in single and multi strain.

  15. Salmonella biofilms

    NARCIS (Netherlands)

    Castelijn, G.A.A.

    2013-01-01

    Biofilm formation by Salmonellaspp. is a problem in the food industry, since biofilms may act as a persistent source of product contamination. Therefore the aim of this study was to obtain more insight in the processes involved and the factors contributing to Salmonellabiofilm

  16. In vitro effect of C2-C18 fatty acids salmonellas

    Czech Academy of Sciences Publication Activity Database

    Savka, Oksana; Skřivanová, E.; Marounek, Milan

    2004-01-01

    Roč. 49, č. 2 (2004), s. 199-202 ISSN 0015-5632 R&D Projects: GA ČR GA523/02/0460 Institutional research plan: CEZ:AV0Z5045916 Keywords : fatty acids Subject RIV: EE - Microbiology, Virology Impact factor: 1.034, year: 2004

  17. Susceptibility of Escherichia coli, Salmonella sp. and Clostridium perfrigens to organic acids and monolaurin

    Czech Academy of Sciences Publication Activity Database

    Skřivanová, E.; Marounek, Milan; Benda, V.; Březina, P.

    2006-01-01

    Roč. 51, č. 3 (2006), s. 81-88 ISSN 0375-8427 R&D Projects: GA AV ČR IBS5045317; GA MZe QF3134 Institutional research plan: CEZ:AV0Z50450515 Keywords : fatty acids * monolaurin * enteropathogenic bacteria Subject RIV: EE - Microbiology, Virology Impact factor: 0.624, year: 2006

  18. Inhibitory Activity of Lactid Acid Bacteria Isolated from Tape Waterlily Seed to Enteric Pathogenic Bacteria (Vibrio cholera, Salmonella typhi, Shigella disentri, and E.coli and Its’ Susceptibility to Antibiotic, Bile Salt and Acidic Condition

    Directory of Open Access Journals (Sweden)

    Iin Khusnul Khotimah

    2012-03-01

    Full Text Available The aim of this research was to observe inhibitory activity of LAB isolated from tape waterlily seed to enteric pathogenic bacteria (Vibrio cholera, Salmonella typhi, Shigella disentri, E.coli ATCC 25922 and it’s susceptibility to antibiotic, in bile salt and under acidic condition. Microbia in the tape ( a fermented product of waterlily seed to showed were Streptococcus thermophilus (IKH-1, Pediococcus pentosaceus (IKH-2 and Leuconostoc mesentroides (IKH-8. Streptococcus thermophillus showed inhibition against the growth of Shigella disentri with inhibition zones 16,28 mm, but did not against the growth of V. Cholera, S. typhi, E.coli. Pediococcus pentosaceus inhibit Vibrio cholera, dan Salmonella thypi with inhibition zones 18,59 mm dan 7,91 mm. So that, Leuconostoc mesenteroides inhibit Salmonella thypi with zones inhibits average 8,25 mm. Chloramfenicol at 0.05 mg concentrations did not show inhibition against the growth of isolated Streptococcus thermophillus, Pediococcus pentosaceus and Leuconostoc mesentroides. These isolates could survive too in bile salt (2% and acidified media (pH 3.   Keyword : The tape of  waterlily seed, LAB, probiotic and enteric pathogenic   KEMAMPUAN PENGHAMBATAN BAKTERI ASAM LAKTAT DARI TAPE BIJI TERATAI TERHADAP PATOGENIK ENTERIK (VIBRIO CHOLERA, SALMONELLA THYPI, SHIGELLA DISENTRI, E. COLI, ANTIBIOTIK, KETAHANANNYA TERHADAP BILE SALT DAN ASAM   ABSTRAK   Penelitian ini bertujuan untuk menguji kemampuan penghambatan bakteri asam laktat yang diisolasi dari tape biji teratai terhadap patogenik enterik (Vibrio cholera, Salmonella thypi, Shigella disentri, E. Coli ATCC 25922, antibiotik, bile salt dan asam. Jenis bakteri yang diketahui tumbuh selama fermentasi tape biji teratai adalah Streptococcus thermopilus (IKH-1, Pediococcus pentosaceus(IKH-2, dan Leuconostoc mesentroides (IKH-8. Pengamatan terhadap uji penghambatan patogenik enterik (Vibrio cholera, Salmonella thypi, Shigella disentri, dan E. Coli ATCC

  19. Pathogen translocation and histopathological lesions in an experimental model of Salmonella Dublin infection in calves receiving lactic acid bacteria and lactose supplements

    Science.gov (United States)

    Zbrun, María V.; Soto, Lorena P.; Bertozzi, Ezequiel; Sequeira, Gabriel J.; Marti, Luis E.; Signorini, Marcelo L.; Armesto, Roberto Rodríguez; Rosmini, Marcelo R.

    2012-01-01

    The purpose of this study was to evaluate the capacity of a lactic acid bacteria (LAB) inoculum to protect calves with or without lactose supplements against Salmonella Dublin infection by evaluating histopathological lesions and pathogen translocation. Fifteen calves were divided into three groups [control group (C-G), a group inoculated with LAB (LAB-G), and a group inoculated with LAB and given lactose supplements (L-LAB-G)] with five, six, and four animals, respectively. The inoculum, composed of Lactobacillus (L.) casei DSPV 318T, L. salivarius DSPV 315T, and Pediococcus acidilactici DSPV 006T, was administered with milk replacer. The LAB-G and L-LAB-G received a daily dose of 109 CFU/kg body weight of each strain throughout the experiment. Lactose was provided to the L-LAB-G in doses of 100 g/day. Salmonella Dublin (2 × 1010 CFU) was orally administered to all animals on day 11 of the experiment. The microscopic lesion index values in target organs were 83%, 70%, and 64.3% (p < 0.05) for the C-G, LAB-G, and L-LAB-G, respectively. Administration of the probiotic inoculum was not fully effective against infection caused by Salmonella. Although probiotic treatment was unable to delay the arrival of pathogen to target organs, it was evident that the inoculum altered the response of animals against pathogen infection. PMID:23000583

  20. Antimicrobial activity of lauric arginate-coated polylactic acid films against Listeria monocytogenes and Salmonella typhimurium on cooked sliced ham.

    Science.gov (United States)

    Theinsathid, Pornpun; Visessanguan, Wonnop; Kruenate, Jittiporn; Kingcha, Yutthana; Keeratipibul, Suwimon

    2012-02-01

    A novel type of environmentally friendly packaging with antibacterial activity was developed from lauric arginate (LAE)-coating of polylactic acid (PLA) films after surface activation using a corona discharge. Scanning electron microscopy (SEM)-based analysis of the LAE/PLA films confirmed the successful coating of LAE on the PLA surface. The mechanical properties of the LAE/PLA films with different levels of LAE-coating (0% to 2.6%[w/w]) were essentially the same as those of the neat PLA film. The antibacterial activity of the LAE/PLA films against Listeria monocytogenes and Salmonella enterica Serovar Typhimurium (S. Typhimurium) was confirmed by a qualitative modified agar diffusion assay and quantitative JIS Z 2801:2000 method. Using the LAE/PLA film as a food-contact antimicrobial packaging for cooked cured ham, as a model system, suggested a potential application to inhibit L. monocytogenes and S. Typhimurium on ham with a 0.07% (w/w) LAE coating on the PLA when high transparency is required, as evidenced from the 2 to 3 log CFU/tested film lower pathogen growth after 7 d storage but even greater antibacterial activity is obtained with a LAE coating level of 2.6% (w/w) but at the cost of a reduced transparency of the finished product. This article shows how we can simply develop functional green packaging of PLA for food with effective and efficient antimicrobial activity by use of LAE coating on the surface via corona discharge. The effectiveness of an innovative antimicrobial LAE-coated PLA film against foodborne pathogens was demonstrated. Importantly, the application of the LAE to form the LAE-coated PLA film can be customized within current film manufacturing lines. © 2012 Institute of Food Technologists®

  1. Prevention of Salmonella infection by contact using intestinal flora of adult birds and/or a mixture of organic acids Controle da transmissão de Salmonella por contato entre aves de exploração comercial pelo uso de flora intestinal de aves adultas e/ou uma mistura de ácidos orgânicos

    Directory of Open Access Journals (Sweden)

    Gláucia Helaine de Oliveira

    2000-06-01

    Full Text Available This study was carried out to assess the ability of competitive exclusion and a mixture of organic acids to prevent Salmonella infection by contact between newly hatched chicks. A bird infected with Salmonella was placed in a box containing non-infected birds, previously treated with a broth culture of faeces of adult birds (CE and/or a mixture of organic acids. The number of Salmonella organisms in the caeca of the contact birds was estimated at 4 and 8 days post-challenge. The birds were infected with Salmonella Typhimurium, Salmonella Enteritidis (both repeated 5 times, Salmonella Agona and Salmonella Infantis (3 repetitions. The same approach was used to test the mixture of organic acids alone. In this case the birds received feed containing 0.8% of a mixture of formic acid (70% and propionic acid (30%. Also, a third trial was carried out with birds inoculated with the broth culture of faeces and fed with feed containing the mixture of organic acids. Appropriate controls were included. Whereas the birds from the control groups and the groups treated with the mixture of organic acids were heavily infected with Salmonella, those pre-treated with CE or CE plus the mixture of organic acids had no viable cells per gram of caecal contents.O presente trabalho avaliou a prevenção da disseminação de quatro sorotipos de Salmonella, de interesse em avicultura e saúde pública (Salmonella Typhimurium, Salmonella Agona, Salmonella Infantis e Salmonella Enteritidis, entre aves recém-nascidas, com o intuito de diminuir a disseminação de salmonelas em rebanhos avícolas por aves que contraíram a infecção pela via vertical. Analisou-se experimentalmente a administração de microbiota intestinal de aves adultas em aves recém-nascidas, a incorporação de uma mistura de ácidos orgânicos na ração e a associação desses dois tratamentos, em grupos onde colocou-se uma ave infectada, para provocar a transmissão por contato. A microbiota

  2. A thermostable Salmonella phage endolysin, Lys68, with broad bactericidal properties against gram-negative pathogens in presence of weak acids.

    Directory of Open Access Journals (Sweden)

    Hugo Oliveira

    Full Text Available Resistance rates are increasing among several problematic Gram-negative pathogens, a fact that has encouraged the development of new antimicrobial agents. This paper characterizes a Salmonella phage endolysin (Lys68 and demonstrates its potential antimicrobial effectiveness when combined with organic acids towards Gram-negative pathogens. Biochemical characterization reveals that Lys68 is more active at pH 7.0, maintaining 76.7% of its activity when stored at 4°C for two months. Thermostability tests showed that Lys68 is only completely inactivated upon exposure to 100°C for 30 min, and circular dichroism analysis demonstrated the ability to refold into its original conformation upon thermal denaturation. It was shown that Lys68 is able to lyse a wide panel of Gram-negative bacteria (13 different species in combination with the outer membrane permeabilizers EDTA, citric and malic acid. While the EDTA/Lys68 combination only inactivated Pseudomonas strains, the use of citric or malic acid broadened Lys68 antibacterial effect to other Gram-negative pathogens (lytic activity against 9 and 11 species, respectively. Particularly against Salmonella Typhimurium LT2, the combinatory effect of malic or citric acid with Lys68 led to approximately 3 to 5 log reductions in bacterial load/CFUs after 2 hours, respectively, and was also able to reduce stationary-phase cells and bacterial biofilms by approximately 1 log. The broad killing capacity of malic/citric acid-Lys68 is explained by the destabilization and major disruptions of the cell outer membrane integrity due to the acidity caused by the organic acids and a relatively high muralytic activity of Lys68 at low pH. Lys68 demonstrates good (thermostability properties that combined with different outer membrane permeabilizers, could become useful to combat Gram-negative pathogens in agricultural, food and medical industry.

  3. SALMONELLA SPECIES

    African Journals Online (AJOL)

    DR. AMINU

    ... of Salmonella species serotypes in relation to age and sex among children, ..... However, most antimicrobials show sufficient selective toxicity to be of value in ... salmonellosis should be given good attention (Barrow et al., 2007). To reduce ...

  4. Salmonella spp. isolated from ready-to-eat pasteurized liquid egg produce: thermal resistance, biochemical profile, and fatty acid analysis

    Science.gov (United States)

    The Egg Products Inspection Act of 1970 requires that egg products in the U.S. must be pasteurized prior to release into commerce. The USDA Food Safety and Inspection Service (FSIS) is responsible for regulating egg products. Salmonellae are infrequently isolated from pasteurized egg products by f...

  5. Inactivation of Salmonella enterica and Listeria monocytogenes in cantaloupe puree by high hydrostatic pressure with/without added ascorbic acid

    Science.gov (United States)

    The objective of this research was to evaluate and develop a method for inactivation of Salmonella enterica and Listeria monocytogenes in cantaloupe puree (CP) by high hydrostatic pressure (HHP). Cantaloupe being the most netted varieties of melons presents a greater risk of pathogen transmission. ...

  6. Effects of dietary additives (potassium diformate/organic acids) as well as influences of grinding intensity (coarse/fine) of diets for weaned piglets experimentally infected with Salmonella Derby or Escherichia coli.

    Science.gov (United States)

    Taube, V A; Neu, M E; Hassan, Y; Verspohl, J; Beyerbach, M; Kamphues, J

    2009-06-01

    The aim of this study was to examine whether and to what extent the addition of potassium diformate (pdf) or free organic acids (fpa) to the diet and the grinding intensity might affect the course of infection and the passage of orally applied Salmonella and Escherichia coli in pigs. Experiments were carried out using 80 reared piglets allotted to four groups. Pigs were fed pelleted diets ad libitum (except during a 15 h feed-withholding-period before infection). The control diet contained finely ground cereals (2 mm screen). To two test diets (also finely ground) 1.2% pdf, 0.9% organic acids (75% formic and 25% propionic acid, fpa) respectively were added. The fourth diet (without acids) was based on coarsely ground cereals (6-mm screen). After experimental infection alternately with S. Derby or E. coli, the course of infection was examined (rectal swab technique). Pigs were sacrificed 4-5 h after a further oral application of approximately 10(9)-10(10) CFU S. Derby or E. coli to determine the counts of Salmonella or E. coli in chyme (classical culture methods). Adding pdf or fpa to the diet led to reduced Salmonella shedding and resulted in significantly lower counts of Salmonella and E. coli in the stomach content indicating an improved efficacy of the stomach barrier. In the distal parts of the digestive tract, the effect was less obvious concerning counts of E. coli, whereas counts of Salmonella were reduced markedly as well. The diet based on coarsely ground cereals failed to demonstrate positive effects concerning infection and passage of orally applied bacteria as well, but this diet was also pelleted and showed unintentionally, comparable amounts of fine particles. Results obtained in this study allow the recommendation of using pdf or organic acids as additives when dietary measures against Salmonella or E. coli in pigs are required.

  7. Impact of spatial organization on a novel auxotrophic interaction among soil microbes.

    Science.gov (United States)

    Jiang, Xue; Zerfaß, Christian; Feng, Song; Eichmann, Ruth; Asally, Munehiro; Schäfer, Patrick; Soyer, Orkun S

    2018-06-01

    A key prerequisite to achieve a deeper understanding of microbial communities and to engineer synthetic ones is to identify the individual metabolic interactions among key species and how these interactions are affected by different environmental factors. Deciphering the physiological basis of species-species and species-environment interactions in spatially organized environments requires reductionist approaches using ecologically and functionally relevant species. To this end, we focus here on a defined system to study the metabolic interactions in a spatial context among the plant-beneficial endophytic fungus Serendipita indica, and the soil-dwelling model bacterium Bacillus subtilis. Focusing on the growth dynamics of S. indica under defined conditions, we identified an auxotrophy in this organism for thiamine, which is a key co-factor for essential reactions in the central carbon metabolism. We found that S. indica growth is restored in thiamine-free media, when co-cultured with B. subtilis. The success of this auxotrophic interaction, however, was dependent on the spatial and temporal organization of the system; the beneficial impact of B. subtilis was only visible when its inoculation was separated from that of S. indica either in time or space. These findings describe a key auxotrophic interaction in the soil among organisms that are shown to be important for plant ecosystem functioning, and point to the potential importance of spatial and temporal organization for the success of auxotrophic interactions. These points can be particularly important for engineering of minimal functional synthetic communities as plant seed treatments and for vertical farming under defined conditions.

  8. Antimicrobial activity of lactic acid bacteria isolated from bekasam against staphylococcus aureus ATCC 25923, escherichia coli ATCC 25922, and salmonella sp

    Science.gov (United States)

    Sari, Melia; Suryanto, Dwi; Yurnaliza

    2018-03-01

    Bekasam is an Indonesian fermented food made of fish. As a fermented food, this food may contain some beneficial bacteria like lactic acid bacteria (LAB), which usually have antimicrobial properties such as organic acid, hydrogen peroxide, and a bacteriocin. A study on antimicrobial activity of LAB isolated from bekasam against some pathogenic bacteria has been conducted. The purpose of this study was to know the ability of crude bacteriocin produced LAB of bekasam against Staphylococcus aureus ATCC 25923, Escherichia coli ATCC 25922, and Salmonella sp. Bekasam sample was taken from South Sumatera. LAB isolation was done using de Man Rogosa and Sharpe agar. A bacterial colony with clear zone was selected and purified to get a single colony. The antagonistic assay of the LAB was conducted in Muller-Hinton agar Selected isolates with higher clearing zone were assayed for antibacterial effect of their crude bacteriocin of different culture incubation time of 6, 9, and 12 hours. The results showed that the crude extract bacteriocin of isolate MS2 of 9 hours culture incubation time inhibited more in Staphylococcus aureus ATCC 25923 with inhibition zone of 13.1 mm, whereas isolate MS9 of 9 hours culture incubation time inhibited more in Escherichia coli ATCC 25922 and Salmonella sp. with inhibition zone of 12.7 and 7.3 mm, respectively.

  9. In vitro combined effect of oregano essential oil and caprylic acid against Salmonella serovars, Escherichia coli O157:H7, Staphylococcus aureus and Listeria monocytogenes

    Directory of Open Access Journals (Sweden)

    Radka Hulánková

    2011-01-01

    Full Text Available In vitro inhibition of foodborne pathogens via action of natural antimicrobials – caprylic acid (CA and essential oil from Origanum vulgare L. (OEO with high carvacrol content (72% was evaluated. For 15 Salmonella strains the minimum inhibitory concentration (MIC determined by broth microdilution method ranged between 3.67–4.33 μl·ml-1 for CA and between 0.48–0.57 μl·ml-1 for OEO. For 7 Listeria monocytogenes strains the MIC ranged between 2.17–2.83 μl·ml-1 for CA and between 0.52–0.58 μl·ml-1 for OEO. Type strains of Escherichia coli O157:H7 and Staphylococcus aureus were tested, too, with MIC of CA 3.60 μl·ml-1 and 3.20 μl·ml-1 and MIC of OEO 0.51 μl·ml-1 and 0.48 μl·ml-1, respectively. Furthermore, it was found that the MIC of CA can be decreased by even low addition (0.05% of citric or acetic acid and to a lesser extent by lactic acid, whereas the MICs of OEO did not notably decrease. Combined application of CA and OEO determined by FIC index led only to an additive effect (0.5 ≤ FIC ≤ 1. Combination of natural additives OEO, CA and eventually acetic or citric acid seems to have the potential to be an effective mixture for inhibition of foodborne pathogens, predominantly Salmonella spp. and L. monocytogenes, even in only slightly acidic food.

  10. A Thermostable Salmonella Phage Endolysin, Lys68, with Broad Bactericidal Properties against Gram-Negative Pathogens in Presence of Weak Acids

    DEFF Research Database (Denmark)

    Oliveira, Hugo; Thiagarajan, Viruthachalam; Walmagh, Maarten

    2014-01-01

    Resistance rates are increasing among several problematic Gram-negative pathogens, a fact that has encouraged the development of new antimicrobial agents. This paper characterizes a Salmonella phage endolysin (Lys68) and demonstrates its potential antimicrobial effectiveness when combined...... with organic acids towards Gram-negative pathogens. Biochemical characterization reveals that Lys68 is more active at pH 7.0, maintaining 76.7% of its activity when stored at 4°C for two months. Thermostability tests showed that Lys68 is only completely inactivated upon exposure to 100°C for 30 min......, and circular dichroism analysis demonstrated the ability to refold into its original conformation upon thermal denaturation. It was shown that Lys68 is able to lyse a wide panel of Gram-negative bacteria (13 different species) in combination with the outer membrane permeabilizers EDTA, citric and malic acid...

  11. Influence of ethanol adaptation on Salmonella enterica serovar Enteritidis survival in acidic environments and expression of acid tolerance-related genes

    Science.gov (United States)

    Aims: Salmonella enterica serovar Enteritidis (S. Enteritidis) can encounter mild ethanol stress during its life cycle. However, adaptation to a stressful condition may affect bacterial resistance to subsequent stresses. Hence, this work was undertaken to investigate the influences of ethanol adapta...

  12. The Transcriptional Heat Shock Response of Salmonella Typhimurium Shows Hysteresis and Heated Cells Show Increased Resistance to Heat and Acid Stress

    DEFF Research Database (Denmark)

    Pin, C.; Hansen, Trine; Munoz-Cuevas, M.

    2012-01-01

    We investigated if the transcriptional response of Salmonella Typhimurium to temperature and acid variations was hysteretic, i.e. whether the transcriptional regulation caused by environmental stimuli showed memory and remained after the stimuli ceased. The transcriptional activity of non......, implying that down-regulation was significantly less synchronized than upregulation. The hysteretic transcriptional response to heat shock was accompanied by higher resistance to inactivation at 50uC as well as cross-resistance to inactivation at pH 3; however, growth rates and lag times at 43uC and at p......H 4.5 were not affected. The exposure to pH 5 only caused up-regulation of 12 genes and this response was neither hysteretic nor accompanied of increased resistance to inactivation conditions. Cellular memory at the transcriptional level may represent a mechanism of adaptation to the environment...

  13. Radiation-induced mutagenicity and lethality in tryptophan-requiring auxotrophs of escherichia coli

    International Nuclear Information System (INIS)

    Xu Rong; Qian Hongwei; Yao Fenying; Gu Shuzhu; Xu Jiaxin; Bi Hekan; Liu Yuying

    1989-01-01

    Mutation and killing caused by X-ray radiation and 60 Co γ-ray radiation were studied in three different tryptophan-requiring auxotrophs (WP2, Wp2A, Cm 891) of Escherichia coli. These testers are sensitive to base pair substitution mutagens. Cm891 carries a R-factor and is more sensitive than WP2 and WP2A to radiation-induced mutation and lethality. The results of the study show that (1) ionizing radiation was mutagenic to E. coli, (2) the order of mutagenic sensitivity among three strains to ionizing radiation was Cm891 > WP2A > WP2, (3) the dose rate of γ-ray influences mutagenicity and lethalty of E. coli strain, (4) the toxicity and mutagenicity of γ-ray were similar to X-ray when Cm891 was tested, however, γ-ray was more toxic and mutagenic than X-ray to WP2A ang WP2

  14. Salmonella typhi

    OpenAIRE

    Mochammad, Hatta

    2008-01-01

    This manuscript could use as research on infectious diseases Multi-locus variable-number tandem repeat analysis differentiated 297 Salmonella enterica serovar Typhi blood culture isolates from Makassar in 76 genotypes and a single unique S. Typhi genotype was isolated from the cholecystectomy specimens of four patients with cholelithiasis. The high diversity in S. Typhi genotypes circulating in Makassar indicates that the number of carriers could be very large, which may complicat...

  15. Use of caprylic acid to control pathogens (Escherichia coli O157:H7 and Salmonella enterica serovar Typhimurium) in apple juice at mild heat temperature.

    Science.gov (United States)

    Kim, S A; Rhee, M S

    2015-11-01

    The aim of this study was to examine the effects of caprylic acid (CA) on pathogens in apple juice having intrinsic organic acids, and to determine any synergistic effects. Bactericidal effects of CA were examined against Escherichia coli O157:H7 and Salmonella Typhimurium present in apple juice at mild heating temperatures. Apple juice containing each of the pathogens was treated with CA (0·1, 0·2, 0·4, 0·6 or 0·8 mmol l(-1)) at 50 or 55°C. Treatment with 0·8 mmol l(-1) (0·013%) CA at 50°C for 5 min or with 0·6 mmol l(-1) (0·010%) CA at 55°C for 5 min resulted in the complete eradication of E. coli O157:H7 (initial population: 7·25-7·34 log CFU ml(-1)). Salmonella Typhimurium were more sensitive than E. coli O157:H7: all bacteria (7·81-7·55 log CFU ml(-1)) were eradicated by treatment with 0·2 mmol l(-1) (0·0032%) CA at 55°C for 5 min or with 0·6 mmol l(-1) CA at 50°C for 5 min. By contrast, when pH-adjusted apple juice (pH 7·0) was treated with 0·8 mmol l(-1) CA, there was no significant difference in bactericidal effects between CA-treated samples and controls (heat treatment alone or heat + 0·1% ethanol treatment). This result suggested that acidic pH in the apple juice boost the antibacterial effects of CA. CA treatment did not affect (P > 0·05) the pH, colour or °Brix of the apple juice. This study highlights the utility of CA as a natural antibacterial agent that can eliminate micro-organisms from apple juice at very low concentrations (≤0·013%) and temperatures (≤55°C) within a short time (≤10 min). The results of our study may contribute to the development of an efficient method for improving the microbiological safety of apple juice. © 2015 The Society for Applied Microbiology.

  16. In vitro and in vivo virulence of Salmonella Typhimurium DT104: a parallelogram approach

    NARCIS (Netherlands)

    Berk, P.A.

    2008-01-01

    Salmonella is present in different food products. In this research it is concluded that Salmonella, which can survive the stomach of humans better (acid resistant bacteria), have a higher probability of causing an infection than Salmonella strains that are less able to survive the stomach (acid

  17. Identification of metabolic pathways essential for fitness of Salmonella Typhimurium in vivo.

    Directory of Open Access Journals (Sweden)

    Lotte Jelsbak

    Full Text Available Bacterial infections remain a threat to human and animal health worldwide, and there is an urgent need to find novel targets for intervention. In the current study we used a computer model of the metabolic network of Salmonella enterica serovar Typhimurium and identified pairs of reactions (cut sets predicted to be required for growth in vivo. We termed such cut sets synthetic auxotrophic pairs. We tested whether these would reveal possible combined targets for new antibiotics by analyzing the performance of selected single and double mutants in systemic mouse infections. One hundred and two cut sets were identified. Sixty-three of these included only pathways encoded by fully annotated genes, and from this sub-set we selected five cut sets involved in amino acid or polyamine biosynthesis. One cut set (asnA/asnB demonstrated redundancy in vitro and in vivo and showed that asparagine is essential for S. Typhimurium during infection. trpB/trpA as well as single mutants were attenuated for growth in vitro, while only the double mutant was a cut set in vivo, underlining previous observations that tryptophan is essential for successful outcome of infection. speB/speF,speC was not affected in vitro but was attenuated during infection showing that polyamines are essential for virulence apparently in a growth independent manner. The serA/glyA cut-set was found to be growth attenuated as predicted by the model. However, not only the double mutant, but also the glyA mutant, were found to be attenuated for virulence. This adds glycine production or conversion of glycine to THF to the list of essential reactions during infection. One pair (thrC/kbl showed true redundancy in vitro but not in vivo demonstrating that threonine is available to the bacterium during infection. These data add to the existing knowledge of available nutrients in the intra-host environment, and have identified possible new targets for antibiotics.

  18. Anti-Salmonella and uric acid-preserving effect of pine bark tannin in composted poultry litter

    Science.gov (United States)

    Poultry litter contains appreciable amounts of uric acid which makes it a good crude protein supplement for ruminants, but the litter must be treated to kill bacterial pathogens. Presently, we examined the antimicrobial and uric acid-preserving activity of pine bark tannin during the early stage of...

  19. In vitro adhesion assay of lactic acid bacteria, Escherichia coli and Salmonella sp. by microbiological and PCR methods

    Directory of Open Access Journals (Sweden)

    Didier Montet

    2006-03-01

    Full Text Available In vitro adhesion assay using Lactobacillus reuteri KUB-AC5 as a test strain has been studied by applying simple PCR reaction together with image analysis and plate count techniques. Critical factor affecting the PCR method was quality and quantity of DNA. The cell lysis technique was modified to optimize this method. Thus, lysozyme and proteinase K were added to lyse the cells, followed by SDS solution to obtain a complete cell lysis. Only PCR products from total cells (TC were obtained, with low consistency, but none from cells bound to mucus (BC at either 0.1 or 0.5 mg/mL concentration. It was hypothesized that the attached cells might not be extracted into the cell suspension. Therefore, 1% SDS solution and 0.1M NaOH were used directly in the extraction. As expected, PCR products were observed when both TC and BC were used as a DNA template. Adhesion appeared at a wide range of 0-45%, with low consistency. Therefore, a simple microbiological method (plate count was used. The extraction of bound cells into cell suspension was critical in this method. Extraction times of 20, 60, 120 and 150 min were tried. Results showed that maximum cell number was obtained with 120 min extraction. L. reuteri KUB-AC5, L. reuteri KUB-AC16, L. reuteri KUB-AC20, L. salivarius KUB-AC21, L. acidophilus KV-1, Escherichia coli E010, Salmonella sp. S003, E. coli ATCC8739, and S. typhimurium ATCC 13311 exhibited adhesion activity of 21.6%, 0.8%, 5.7%, 1.1%, 23.1%, 10.7%, 10.3%, 4.4% and 3.2%, respectively. Among the 9 types of microorganisms tested L. acidophilus KV-1 and L. reuteri KUB-AC5 showed higher adhesion activity than the others.

  20. Salmonella Infections - Multiple Languages

    Science.gov (United States)

    ... Are Here: Home → Multiple Languages → All Health Topics → Salmonella Infections URL of this page: https://medlineplus.gov/ ... V W XYZ List of All Topics All Salmonella Infections - Multiple Languages To use the sharing features ...

  1. Production of recombinant Bombyx mori nucleopolyhedrovirus in silkworm by intrahaemocoelic injection with invasive diaminopimelate auxotrophic Escherichia coli containing BmNPV-Bacmid.

    Science.gov (United States)

    Sun, Jingchen; Yao, Lunguang; Yao, Ning; Xu, Hua; Jin, Pengfei; Kan, Yunchao

    2010-12-01

    The present study elaborates a cost-effective and transfectant-free method for generating recombinant Bombyx mori (silkworm) nucleopolyhedrovirus in silkworm larvae and pupae by injecting invasive Escherichia coli carrying BmBacmid [BmNPV (B. mori nucleopolyhedrovirus)-Bacmid] into larval haemocoel. Up to 109 PFU (plaque-forming units)/ml of infective recombinant baculovirus was generated in the silkworm by intrahaemocoelic injection with 106 DAP (diaminopimelic acid) auxotrophic and BmBacmid containing E. coli cells expressing both invasin and listeriolysin. Thus 1 ml of overnight culture of E. coli is sufficient to inject more than 2000 larvae, while DAP costing up to $1 is enough to inject about 4000 larvae. Recombinant proteins can be controlled to be expressed mainly in pupae by adjusting the injection dose, too. In this new method, many original manipulations have been eliminated, including BmBacmid preparation and the subsequent complex transfection procedures. Hence it is a time- and cost-saving means for large-scale injection of B. mori for recombinant baculovirus production in comparison with the traditional transfection methods, which may play an important role in the industrial development of the BmNPV-silkworm bioreactor.

  2. Phosphatidylserine biosynthesis in cultured Chinese hamster ovary cells. II. Isolation and characterization of phosphatidylserine auxotrophs

    International Nuclear Information System (INIS)

    Kuge, O.; Nishijima, M.; Akamatsu, Y.

    1986-01-01

    Chinese hamster ovary (CHO) cell mutants that required exogenously added phosphatidylserine for cell growth were isolated by using the replica technique with polyester cloth, and three such mutants were characterized. Labeling experiments on intact cells with 32 Pi and L-[U- 14 C]serine revealed that a phosphatidylserine auxotroph, designated as PSA-3, was strikingly defective in phosphatidylserine biosynthesis. When cells were grown for 2 days without phosphatidylserine, the phosphatidylserine content of PSA-3 was about one-third of that of the parent. In extracts of the mutant, the enzymatic activity of the base-exchange reaction of phospholipids with serine producing phosphatidylserine was reduced to 33% of that in the parent; in addition, the activities of base-exchange reactions of phospholipids with choline and ethanolamine in the mutant were also reduced to 1 and 45% of those in the parent, respectively. Furthermore, it was demonstrated that the serine-exchange activity in the parent was inhibited approximately 60% when choline was added to the reaction mixture whereas that in the mutant was not significantly affected. From the results presented here, we conclude the following. There are at least two kinds of serine-exchange enzymes in CHO cells; one (serine-exchange enzyme I) can catalyze the base-exchange reactions of phospholipids with serine, choline, and ethanolamine while the other (serine-exchange enzyme II) does not use the choline as a substrate. Serine-exchange enzyme I, in which mutant PSA-3 is defective, plays a major role in phosphatidylserine biosynthesis in CHO cells. Serine-exchange enzyme I is essential for the growth of CHO cells

  3. Preservation of genes involved in sterol metabolism in cholesterol auxotrophs: facts and hypotheses.

    Directory of Open Access Journals (Sweden)

    Giovanna Vinci

    Full Text Available BACKGROUND: It is known that primary sequences of enzymes involved in sterol biosynthesis are well conserved in organisms that produce sterols de novo. However, we provide evidence for a preservation of the corresponding genes in two animals unable to synthesize cholesterol (auxotrophs: Drosophila melanogaster and Caenorhabditis elegans. PRINCIPAL FINDINGS: We have been able to detect bona fide orthologs of several ERG genes in both organisms using a series of complementary approaches. We have detected strong sequence divergence between the orthologs of the nematode and of the fruitfly; they are also very divergent with respect to the orthologs in organisms able to synthesize sterols de novo (prototrophs. Interestingly, the orthologs in both the nematode and the fruitfly are still under selective pressure. It is possible that these genes, which are not involved in cholesterol synthesis anymore, have been recruited to perform different new functions. We propose a more parsimonious way to explain their accelerated evolution and subsequent stabilization. The products of ERG genes in prototrophs might be involved in several biological roles, in addition to sterol synthesis. In the case of the nematode and the fruitfly, the relevant genes would have lost their ancestral function in cholesterogenesis but would have retained the other function(s, which keep them under pressure. CONCLUSIONS: By exploiting microarray data we have noticed a strong expressional correlation between the orthologs of ERG24 and ERG25 in D. melanogaster and genes encoding factors involved in intracellular protein trafficking and folding and with Start1 involved in ecdysteroid synthesis. These potential functional connections are worth being explored not only in Drosophila, but also in Caenorhabditis as well as in sterol prototrophs.

  4. 78 FR 42526 - Salmonella

    Science.gov (United States)

    2013-07-16

    ...] Salmonella Contamination of Dry Dog Food; Withdrawal of Compliance Policy Guide AGENCY: Food and Drug... the withdrawal of the compliance policy guide (CPG) entitled ``Sec. 690.700 Salmonella Contamination... entitled ``Sec. 690.700 Salmonella Contamination of Dry Dog Food (CPG 690.700)'' on October 1, 1980. CPG...

  5. pH-, Lactic Acid-, and Non-Lactic Acid-Dependent Activities of Probiotic Lactobacilli against Salmonella enterica Serovar Typhimurium

    OpenAIRE

    Fayol-Messaoudi, Domitille; Berger, Cédric N.; Coconnier-Polter, Marie-Hélène; Liévin-Le Moal, Vanessa; Servin, Alain L.

    2005-01-01

    The mechanism(s) underlying the antibacterial activity of probiotic Lactobacillus strains appears to be multifactorial and includes lowering of the pH and the production of lactic acid and of antibacterial compounds, including bacteriocins and nonbacteriocin, non-lactic acid molecules. Addition of Dulbecco's modified Eagle's minimum essential medium to the incubating medium delays the killing activity of lactic acid. We found that the probiotic strains Lactobacillus johnsonii La1, Lactobacill...

  6. Combining Lactic Acid Spray with Near-Infrared Radiation Heating To Inactivate Salmonella enterica Serovar Enteritidis on Almond and Pine Nut Kernels.

    Science.gov (United States)

    Ha, Jae-Won; Kang, Dong-Hyun

    2015-07-01

    The aim of this study was to investigate the efficacy of near-infrared radiation (NIR) heating combined with lactic acid (LA) sprays for inactivating Salmonella enterica serovar Enteritidis on almond and pine nut kernels and to elucidate the mechanisms of the lethal effect of the NIR-LA combined treatment. Also, the effect of the combination treatment on product quality was determined. Separately prepared S. Enteritidis phage type (PT) 30 and non-PT 30 S. Enteritidis cocktails were inoculated onto almond and pine nut kernels, respectively, followed by treatments with NIR or 2% LA spray alone, NIR with distilled water spray (NIR-DW), and NIR with 2% LA spray (NIR-LA). Although surface temperatures of nuts treated with NIR were higher than those subjected to NIR-DW or NIR-LA treatment, more S. Enteritidis survived after NIR treatment alone. The effectiveness of NIR-DW and NIR-LA was similar, but significantly more sublethally injured cells were recovered from NIR-DW-treated samples. We confirmed that the enhanced bactericidal effect of the NIR-LA combination may not be attributable to cell membrane damage per se. NIR heat treatment might allow S. Enteritidis cells to become permeable to applied LA solution. The NIR-LA treatment (5 min) did not significantly (P > 0.05) cause changes in the lipid peroxidation parameters, total phenolic contents, color values, moisture contents, and sensory attributes of nut kernels. Given the results of the present study, NIR-LA treatment may be a potential intervention for controlling food-borne pathogens on nut kernel products. Copyright © 2015, American Society for Microbiology. All Rights Reserved.

  7. Determining the Extremes of the Cellular NAD(H) Level by Using an Escherichia coli NAD+-Auxotrophic Mutant ▿

    OpenAIRE

    Zhou, Yongjin; Wang, Lei; Yang, Fan; Lin, Xinping; Zhang, Sufang; Zhao, Zongbao K.

    2011-01-01

    NAD (NAD+) and its reduced form (NADH) are omnipresent cofactors in biological systems. However, it is difficult to determine the extremes of the cellular NAD(H) level in live cells because the NAD+ level is tightly controlled by a biosynthesis regulation mechanism. Here, we developed a strategy to determine the extreme NAD(H) levels in Escherichia coli cells that were genetically engineered to be NAD+ auxotrophic. First, we expressed the ntt4 gene encoding the NAD(H) transporter in the E. co...

  8. Use of Potential Probiotic Lactic Acid Bacteria (LAB) Biofilms for the Control of Listeria monocytogenes, Salmonella Typhimurium, and Escherichia coli O157:H7 Biofilms Formation.

    Science.gov (United States)

    Gómez, Natacha C; Ramiro, Juan M P; Quecan, Beatriz X V; de Melo Franco, Bernadette D G

    2016-01-01

    Use of probiotic biofilms can be an alternative approach for reducing the formation of pathogenic biofilms in food industries. The aims of this study were (i) to evaluate the probiotic properties of bacteriocinogenic (Lactococcus lactis VB69, L. lactis VB94, Lactobacillus sakei MBSa1, and Lactobacillus curvatus MBSa3) and non-bacteriocinogenic (L. lactis 368, Lactobacillus helveticus 354, Lactobacillus casei 40, and Weissela viridescens 113) lactic acid bacteria (LAB) isolated from Brazilian's foods and (ii) to develop protective biofilms with these strains and test them for exclusion of Listeria monocytogenes, Escherichia coli O157:H7, and Salmonella Typhimurium. LAB were tested for survival in acid and bile salt conditions, surface properties, biosurfactant production, β-galactosidase and gelatinase activity, antibiotic resistance and presence of virulence genes. Most strains survived exposure to pH 2 and 4% bile salts. The highest percentages of auto-aggregation were obtained after 24 h of incubation. Sixty-seven percentage auto-aggregation value was observed in W. viridescens 113 and Lactobacillus curvatus MBSa3 exhibited the highest co-aggregation (69% with Listeria monocytogenes and 74.6% with E. coli O157:H7), while the lowest co-aggregation was exhibited by W. viridescens 113 (53.4% with Listeria monocytogenes and 38% with E. coli O157:H7). Tests for hemolytic activity, bacterial cell adherence with xylene, and drop collapse confirmed the biosurfactant-producing ability of most strains. Only one strain (L. lactis 368) produced β-galactosidase. All strains were negative for virulence genes cob, ccf, cylLL, cylLs, cyllM, cylB, cylA and efaAfs and gelatinase production. The antibiotic susceptibility tests indicated that the MIC for ciprofloxacin, clindamycin, gentamicin, kanamycin, and streptomycin did not exceed the epidemiological cut-off suggested by the European Food Safety Authority. Some strains were resistant to one or more antibiotics and resistance

  9. Transcriptomic analysis of Salmonella desiccation resistance.

    Science.gov (United States)

    Li, Haiping; Bhaskara, Anuhya; Megalis, Christina; Tortorello, Mary Lou

    2012-12-01

    The survival of Salmonella in low moisture foods and processing environments remains a great challenge for the food industry and public health. To explore the mechanisms of Salmonella desiccation resistance, we studied the transcriptomic responses in Salmonella Tennessee (Tennessee), using Salmonella Typhimurium LT2 (LT2), a strain weakly resistant to desiccation, as a reference strain. In response to 2 h of air-drying at 11% equilibrated relative humidity, approximately one-fourth of the open reading frames (ORFs) in the Tennessee genome and one-fifth in LT2 were differentially expressed (>2-fold). Among all differentially expressed functional groups (>5-fold) in both strains, the expression fold change associated with fatty acid metabolism was the highest, and constituted 51% and 35% of the total expression fold change in Tennessee and LT2, respectively. Tennessee showed greater changes in expression of genes associated with stress response and envelope modification than LT2, while showing lesser changes in protein biosynthesis expression. Expression of flagella genes was significantly more inhibited in stationary phase cells of Tennessee than LT2 both before and after desiccation. The accumulation of the osmolyte trehalose was significantly induced by desiccation in Tennessee, but no increase was detectable in LT2, which is consistent with the expression patterns of the entire trehalose biosynthesis and degradation pathways in both strains. Results from this study present a global view of the dynamic desiccation responses in Salmonella, which will guide future research efforts to control Salmonella in low moisture environments.

  10. Evaluation of a Solid Dispersion of Curcumin With Polyvinylpyrrolidone and Boric Acid Against Salmonella Enteritidis Infection and Intestinal Permeability in Broiler Chickens: A Pilot Study

    Directory of Open Access Journals (Sweden)

    Daniel Hernandez-Patlan

    2018-06-01

    Full Text Available In the present study, in vitro assays were conducted to evaluate the solubility of curcumin (CUR alone or with polyvinylpyrrolidone (PVP at different pH, as well as its permeability in Caco-2 cells. Results confirmed that the solid dispersion of CUR with PVP (CUR/PVP at a 1:9 ratio, significantly increased (P < 0.05 solubility and permeability compared to CUR alone. Then, the antimicrobial activity of CUR/PVP, boric acid (BA, and a combination of 0.5% CUR/PVP and 0.5% BA (CUR/PVP-BA against Salmonella Enteritidis (SE was determined using an in vitro digestion model that simulates crop, proventriculus, and intestine. The results revealed that in the proventriculus and intestinal compartments significant reductions of SE were observed in all the experimental treatments, but 1% BA eliminated SE in the intestinal compartment and CUR/PVP-BA showed a synergistic effect on antimicrobial activity against SE. To complement these findings, two independent in vivo trials were conducted to determine the effect of 0.1% CUR/PVP; 0.1% BA; or the combination of 0.05% CUR/PVP (1:9 ratio and 0.05% BA (CUR/PVP-BA on the antimicrobial activity against SE, intestinal permeability and inflammatory responses in broiler chickens. BA at 0.1% had no significant in vivo effects against SE. However, the combination of 0.05% BA and 0.05% CUR/PVP and 0.05% BA was sufficient to reduce crop and intestinal SE colonization in broiler chickens in two independent trials, confirming the synergic effect between them. A similar antimicrobial impact against SE intestinal colonization was observed in chickens treated with 0.1% CUR/PVP at a 1:9 ratio, which could be due to the increase in solubility of CUR by PVP. Furthermore, 0.1% CUR/PVP reduced the intestinal permeability of FITC-d and total intestinal IgA, as well as increase the activity of SOD when compared to control, while, CUR/PVP-BA only decreased SOD activity. Further studies to confirm and expand the in vivo results obtained

  11. Efficacy of a Blend of Sulfuric Acid and Sodium Sulfate against Shiga Toxin-Producing Escherichia coli, Salmonella, and Nonpathogenic Escherichia coli Biotype I on Inoculated Prerigor Beef Surface Tissue.

    Science.gov (United States)

    Scott-Bullard, Britteny R; Geornaras, Ifigenia; Delmore, Robert J; Woerner, Dale R; Reagan, James O; Morgan, J Bred; Belk, Keith E

    2017-12-01

    A study was conducted to investigate the efficacy of a sulfuric acid-sodium sulfate blend (SSS) against Escherichia coli O157:H7, non-O157 Shiga toxin-producing E. coli (STEC), Salmonella, and nonpathogenic E. coli biotype I on prerigor beef surface tissue. The suitability of using the nonpathogenic E. coli as a surrogate for in-plant validation studies was also determined by comparing the data obtained for the nonpathogenic inoculum with those for the pathogenic inocula. Prerigor beef tissue samples (10 by 10 cm) were inoculated (ca. 6 log CFU/cm 2 ) on the adipose side in a laboratory-scale spray cabinet with multistrain mixtures of E. coli O157:H7 (5 strains), non-O157 STEC (12 strains), Salmonella (6 strains), or E. coli biotype I (5 strains). Treatment parameters evaluated were two SSS pH values (1.5 and 1.0) and two spray application pressures (13 and 22 lb/in 2 ). Untreated inoculated beef tissue samples served as controls for initial bacterial populations. Overall, the SSS treatments lowered inoculated (6.1 to 6.4 log CFU/cm 2 ) bacterial populations by 0.6 to 1.5 log CFU/cm 2 (P SSS was applied to samples inoculated with any of the tested E. coli inocula; however, solution pH did have a significant effect (P SSS was applied to samples inoculated with Salmonella. Results indicated that the response of the nonpathogenic E. coli inoculum to the SSS treatments was similar (P ≥ 0.05) to that of the pathogenic inocula tested, making the E. coli biotype I strains viable surrogate organisms for in-plant validation of SSS efficacy on beef. The application of SSS at the tested parameters to prerigor beef surface tissue may be an effective intervention for controlling pathogens in a commercial beef harvest process.

  12. Genomics of Salmonella Species

    Science.gov (United States)

    Canals, Rocio; McClelland, Michael; Santiviago, Carlos A.; Andrews-Polymenis, Helene

    Progress in the study of Salmonella survival, colonization, and virulence has increased rapidly with the advent of complete genome sequencing and higher capacity assays for transcriptomic and proteomic analysis. Although many of these techniques have yet to be used to directly assay Salmonella growth on foods, these assays are currently in use to determine Salmonella factors necessary for growth in animal models including livestock animals and in in vitro conditions that mimic many different environments. As sequencing of the Salmonella genome and microarray analysis have revolutionized genomics and transcriptomics of salmonellae over the last decade, so are new high-throughput sequencing technologies currently accelerating the pace of our studies and allowing us to approach complex problems that were not previously experimentally tractable.

  13. Secretion of Rhoptry and Dense Granule Effector Proteins by Nonreplicating Toxoplasma gondii Uracil Auxotrophs Controls the Development of Antitumor Immunity.

    Directory of Open Access Journals (Sweden)

    Barbara A Fox

    2016-07-01

    Full Text Available Nonreplicating type I uracil auxotrophic mutants of Toxoplasma gondii possess a potent ability to activate therapeutic immunity to established solid tumors by reversing immune suppression in the tumor microenvironment. Here we engineered targeted deletions of parasite secreted effector proteins using a genetically tractable Δku80 vaccine strain to show that the secretion of specific rhoptry (ROP and dense granule (GRA proteins by uracil auxotrophic mutants of T. gondii in conjunction with host cell invasion activates antitumor immunity through host responses involving CD8α+ dendritic cells, the IL-12/interferon-gamma (IFN-γ TH1 axis, as well as CD4+ and CD8+ T cells. Deletion of parasitophorous vacuole membrane (PVM associated proteins ROP5, ROP17, ROP18, ROP35 or ROP38, intravacuolar network associated dense granule proteins GRA2 or GRA12, and GRA24 which traffics past the PVM to the host cell nucleus severely abrogated the antitumor response. In contrast, deletion of other secreted effector molecules such as GRA15, GRA16, or ROP16 that manipulate host cell signaling and transcriptional pathways, or deletion of PVM associated ROP21 or GRA3 molecules did not affect the antitumor activity. Association of ROP18 with the PVM was found to be essential for the development of the antitumor responses. Surprisingly, the ROP18 kinase activity required for resistance to IFN-γ activated host innate immunity related GTPases and virulence was not essential for the antitumor response. These data show that PVM functions of parasite secreted effector molecules, including ROP18, manipulate host cell responses through ROP18 kinase virulence independent mechanisms to activate potent antitumor responses. Our results demonstrate that PVM associated rhoptry effector proteins secreted prior to host cell invasion and dense granule effector proteins localized to the intravacuolar network and host nucleus that are secreted after host cell invasion coordinately

  14. Determining the Extremes of the Cellular NAD(H) Level by Using an Escherichia coli NAD+-Auxotrophic Mutant ▿

    Science.gov (United States)

    Zhou, Yongjin; Wang, Lei; Yang, Fan; Lin, Xinping; Zhang, Sufang; Zhao, Zongbao K.

    2011-01-01

    NAD (NAD+) and its reduced form (NADH) are omnipresent cofactors in biological systems. However, it is difficult to determine the extremes of the cellular NAD(H) level in live cells because the NAD+ level is tightly controlled by a biosynthesis regulation mechanism. Here, we developed a strategy to determine the extreme NAD(H) levels in Escherichia coli cells that were genetically engineered to be NAD+ auxotrophic. First, we expressed the ntt4 gene encoding the NAD(H) transporter in the E. coli mutant YJE001, which had a deletion of the nadC gene responsible for NAD+ de novo biosynthesis, and we showed NTT4 conferred on the mutant strain better growth in the presence of exogenous NAD+. We then constructed the NAD+-auxotrophic mutant YJE003 by disrupting the essential gene nadE, which is responsible for the last step of NAD+ biosynthesis in cells harboring the ntt4 gene. The minimal NAD+ level was determined in M9 medium in proliferating YJE003 cells that were preloaded with NAD+, while the maximal NAD(H) level was determined by exposing the cells to high concentrations of exogenous NAD(H). Compared with supplementation of NADH, cells grew faster and had a higher intracellular NAD(H) level when NAD+ was fed. The intracellular NAD(H) level increased with the increase of exogenous NAD+ concentration, until it reached a plateau. Thus, a minimal NAD(H) level of 0.039 mM and a maximum of 8.49 mM were determined, which were 0.044× and 9.6× those of wild-type cells, respectively. Finally, the potential application of this strategy in biotechnology is briefly discussed. PMID:21742902

  15. Dithizone staining of intracellular zinc: an unexpected and versatile counterscreen for auxotrophic marker genes in Saccharomyces cerevisiae.

    Directory of Open Access Journals (Sweden)

    Daniel S Yuan

    Full Text Available Auxotrophic marker genes such as URA3, LEU2, and HIS3 in Saccharomyces cerevisiae have long been used to select cells that have been successfully transformed with recombinant DNA. A longstanding challenge in working with these genes is that counterselection procedures are often lacking. This paper describes the unexpected discovery of a simple plate assay that imparts a bright red stain to cells experiencing nutritional stress from the lack of a marker gene. The procedure specifically stains a zinc-rich vesicular compartment analogous to the zinc-rich secretory vesicles found in insulin-secreting pancreatic islet cells and glutamate-secreting neurons. Staining was greatly diminished in zap1 mutants, which lack a homeostatic activator of zinc uptake, and in cot1 zrc1 double mutants, which lack the two yeast homologs of mammalian vesicle-specific zinc export proteins. Only one of 93 strains with temperature-sensitive alleles of essential genes exhibited an increase in dithizone staining at its non-permissive temperature, indicating that staining is not simply a sign of growth-arrested or dying cells. Remarkably, the procedure works with most commonly used marker genes, highlights subtle defects, uses no reporter constructs or expensive reagents, requires only a few hours of incubation, yields visually striking results without any instrumentation, and is not toxic to the cells. Many potential applications exist for dithizone staining, both as a versatile counterscreen for auxotrophic marker genes and as a powerful new tool for the genetic analysis of a biomedically important vesicular organelle.

  16. Broad-range (pan) Salmonella and Salmonella serotype typhi-specific real-time PCR assays: potential tools for the clinical microbiologist.

    Science.gov (United States)

    Farrell, John J; Doyle, Laura J; Addison, Rachel M; Reller, L Barth; Hall, Geraldine S; Procop, Gary W

    2005-03-01

    We describe broad-range salmonellae (ie, Salmonella) and Salmonella serotype Typhi-specific LightCycler (Roche Diagnostics, Indianapolis, IN) real-time polymerase chain reaction assays. We validated these with a battery of 280 bacteria, 108 of which were salmonellae representing 20 serotypes. In addition, 298 isolates from 170 clinical specimens that were suspected to possibly represent Salmonella were tested with the pan- Salmonella assay. Finally, the pan-Salmonella assay also was used to test DNA extracts from 101 archived, frozen stool specimens, 55 of which were culture-positive for salmonellae. Both assays were 100% sensitive and specific when cultured isolates of the battery were tested. The pan- Salmonella assay also characterized correctly all salmonellae on the primary isolation agar and was 96% sensitive (53/55) and 96% specific (49/51) when nucleic acid extracts from direct stool specimens were tested. These assays represent potential tools the clinical microbiologist could use to screen suspect isolates or stool specimens for Salmonella.

  17. Sensitivitas Salmonella Sp. Penyebab Demam Tifoid Terhadap Beberapa Antibiotik di Rumah Sakit Immanuel Bandung

    Directory of Open Access Journals (Sweden)

    Yanti Mulyana

    2009-09-01

    Full Text Available Typhoid fever is an enteric fever caused by Salmonella sp. especially Salmonella typhi and Salmonella paratyphi. Various antibiotics used for therapy beside chloramphenicol as drug of choice. Non rational use of antibiotics may result increasing of resistence in bacteria. The aim of the research is to know the sensitivity of Salmonella typhi and Salmonella paratyphi to some antibiotics. The purpose is to gather information about antibiotics which are still effective for typhoid fever and enteric therapy. Salmonella typhi and Salmonella paratyphi strain from positive cultures diagnose typhoid fever patients at Immanuel Hospital Bandung during 2004-2007. The method of resistance is Kirby Bauer's disk diffusion assay with NCCLS standard. The disk antibiotics used are amoxicillin, amoxicillinclavulanic acid, chloramphenicol, ciprofloxacin, ceftriaxone, trimethoprim, and trimethoprim-sulfamethoxazole. The result showed penicillin group, amoxicillin and amoxicillin-clavulanic acid had 96.3–99.68% sensitive against Salmonella sp. Sensitivity of chloramphenicol as drug of choice of typhoid fever still 99.05%. Since the sensitivity less than 100%, it means there was about 8% resistence. Thats why eventhough this data can be used as empiric therapy, the writer suggest to do sensitivity test to Salmonella sp. that caused typhoid to get rationally dan effective treatment. From the result, it's concluded that Salmonella typhi and Salmonella paratyphi are still sensitive to all that antibiotics.

  18. Prevalence, serovars, phage types, and antibiotic susceptibilities of Salmonella strains isolated from animals in the United Arab Emirates from 1996 to 2009.

    Science.gov (United States)

    Münch, Sebastian; Braun, Peggy; Wernery, Ulrich; Kinne, Jörg; Pees, Michael; Flieger, Antje; Tietze, Erhard; Rabsch, Wolfgang

    2012-10-01

    The aim of this study was to give some insights into the prevalence, serovars, phage types, and antibiotic resistances of Salmonella from animal origin in the United Arab Emirates. Data on diagnostic samples from animals (n = 20,871) examined for Salmonella between 1996 and 2009 were extracted from the databases of the Central Veterinary Research Laboratory in Dubai and from typed strains (n = 1052) from the Robert Koch Institute, Wernigerode Branch in Germany and analyzed for general and animal-specific trends. Salmonella was isolated from 1,928 (9 %) of the 20,871 samples examined. Among the 1,052 typed strains, most were from camels (n = 232), falcons (n = 166), bustards (n = 101), antelopes (n = 66), and horses (n = 63). The predominant serovars were Salmonella Typhimurium (25 %), Salmonella Kentucky (8 %), followed by Salmonella Frintrop (7 %), and Salmonella Hindmarsh (5 %). When analyzed by animal species, the most frequent serovars in camels were Salmonella Frintrop (28 %) and Salmonella Hindmarsh (21 %), in falcons Salmonella Typhimurium (32 %), in bustards Salmonella Kentucky (19 %), in antelopes Salmonella Typhimurium (9 %), and in horses Salmonella Typhimurium (17 %) and S. Kentucky (16 %). Resistance of all typed Salmonella strains (n = 1052) was most often seen to tetracycline (23 %), streptomycin (22 %), nalidixic acid (18 %), and ampicillin (15 %). These data show trends in the epidemiology of Salmonella in different animal species which can be used as a base for future prevention, control, and therapy strategies.

  19. Antibiotic susceptibility of Salmonella spp.: a comparison of two surveys with a 5 years interval

    Directory of Open Access Journals (Sweden)

    Gordana Mijović

    2012-02-01

    Full Text Available Salmonella infections are one of the major global public health problems. During the last decade, antibiotic resistance and multiresistance of Salmonella spp. have increased a great deal, especially in developing countries with an increased and indiscriminate use of antibiotics in the treatment of humans and animals. This study aims to investigate and compare antimicrobial susceptibility patterns of Salmonella during 2005 and 2010.A total of 186 Salmonella strain during 2005 and 140 Salmonella strain during 2010 were isolated from stool specimens using standard methods. The isolates were confirmed as Salmonella by using a battery of biochemical reactions. Specific antisera were used for serologic characterization of Salmonella strain. Antimicrobial susceptibility testing was performed by standard disk diffusion method using ampicillin, trimethoprim-sulfamethoxasole, ceftriaxon, chloramphenicol, nalidixic acid and ciprofloxacin.One hundred eighty (96.8% of 186 isolated Salmonella strains in 2005, and 133 (95% of 140 isolated Salmonella strain in 2010 are recognized as Salmonella Enteritidis. Sensitivity of Salmonella isolates during 2005 and 2010 were 91.9% and 92.9% to ampicillin, 95.7% and 97.1% to trimethoprim-sulfamethoxasole, 99.5% and 100% to chloramphenicol, 99.5% and 100% to ciprofloxacin, 98.9% and 97.1% to ceftriaxon, 73.1% and 95.7% to nalidixic acid, respectively.Sensitivity of Salmonella isolates to all tested antimicrobial agents except to ceftriaxon was been slightly improved over testing period. Resistance rate to ceftriaxon was higher in 2010 than in 2005, and this fact deserves attention. Significantly increase susceptibility rate to nalidixic acid was observed between the two surveys

  20. Prevalence and characterization of Salmonella among humans in Ghana

    DEFF Research Database (Denmark)

    Andoh, Linda Aurelia; Ahmed, Shabana; Olsen, John Elmerdahl

    2017-01-01

    Background Non-typhoidal Salmonella (NTS) is a public health problem worldwide and particularly in Africa with high disease burden. This study characterized Salmonella isolates from humans in Ghana to determine serovar distribution, phage types, and antimicrobial resistance. Further, the clonal...... relatedness among isolates was determined. Methods One hundred and thirty-seven Salmonella isolates (111 clinical and 26 public toilet) were characterized using standard serotyping, phage typing, and antimicrobial susceptibility testing methods. The molecular epidemiology of common serovars (Salmonella....... Fifty-eight (n = 58/112; 54.5%) strains were multi-resistant with low resistance to cephalosporins ceftazidime (8.0%), cefotaxime (4.5%), and cefoxitin (2.7%) with synergy to clavulanic acid indicating possible ESBLs. Isolates showed high resistance to trimethoprim (66.1%), tetracycline (61...

  1. Gamma irradiation increase the sensitivity of Salmonella to antibiotics

    International Nuclear Information System (INIS)

    Ben Miloud, Najla; Barkallah, Insaf

    2008-01-01

    In order to study the effect of ionizing radiation on the resistance of Salmonella to antibiotics, four strains of Salmonella were isolated from foods, The different strains used in the present study are (S. Hadar isolate 287, S. Hadar isolate 63, S. Cerro isolate 291, S. Zanzibar isolate 1103), antibiogram analyses were made to test the in vitro-sensitivity of irradiated Salmonella isolates to different antibiotics.The analyse of Control and exposed antibiograms showed that gamma radiation have increased the sensitivity of Salmonella isolates to Cefalotin, Chloramphenicol, Nalidixic acid, Spiramycin and Gentamycin excepted S. Hadar isolate 287 that was resistant to Cefalotin and became sensitive after irradiation. Statistical analyses showed that the effect of different irradiation dose treatment on the antibiotic sensitivity is increasingly significant. The irradiation didn't induce modifications of the sensitivity to other antibiotics,probably because of their nature, of their penetration mode inside the cell or their action way

  2. Occurrence of Salmonella spp. in broiler chicken carcasses and their susceptibility to antimicrobial agents

    Science.gov (United States)

    Duarte, Dalila Angélica Moliterno; Ribeiro, Aldemir Reginato; Vasconcelos, Ana Mércia Mendes; Santos, Sylnei Barros; Silva, Juliana Vital Domingos; de Andrade, Patrícia Lúcia Arruda; de Arruda Falcão, Lúcia Sadae Pereira da Costa

    2009-01-01

    The present study was carried out to evaluate the occurrence of Salmonellae in broiler chicken carcasses and to determine the antimicrobial resistance profile of the isolated strains. Twenty-five out of the 260 broiler chicken carcasses samples (9.6%) were positive for Salmonella. S. Enteritidis was the most frequent serovar. Nineteen Salmonella isolates were tested for antimicrobial resistance, and the results indicated that 94.7% were resistant to at least one antimicrobial agent. Resistance to streptomycin (73.7%), nitrofurantoin (52.3%), tetracycline (31.6%), and nalidixic acid (21%) were the prevalent amongst Salmonella strains tested. PMID:24031401

  3. Coconut and Salmonella Infection

    Science.gov (United States)

    Schaffner, Carl P.; Mosbach, Klaus; Bibit, Venuso C.; Watson, Colin H.

    1967-01-01

    Raw, unprocessed coconut supports the growth of salmonellae as well as that of other enteric bacteria, salmonellae being particularly resistant to subsequent desiccation. Original contamination is not due to carriers or to polluted water supplies, but to contact with bacteria-containing soils followed by dispersion via infected coconut milk and shells. Pasteurization of raw coconut meat in a water bath at 80 C for 8 to 10 min effectively killed such bacteria, did not injure the product, and provided a prophylactic method now widely used by the coconut industry. PMID:5340650

  4. Impact of egg holding temperatures on the recovery of Salmonella from eggshells and stainless steel coupons

    Science.gov (United States)

    This experiment was conducted to determine the impact of egg holding temperature on the ability to recover Salmonella from eggshells after 24 h. Salmonella enterica Enteritidis (nalidixic acid resistant marker strain) inoculated eggshells and stainless steel coupons (SSC, 14 mm diameter) were held a...

  5. Identification of ergosterol and inhibition of sterol synthesis by Δ5-sterols in GL7, an auxotrophic mutant of yeast

    International Nuclear Information System (INIS)

    Dhanuka, I.C.

    1988-01-01

    Synthesis of ergosterol was demonstrated in the GL7 mutant of Saccharomyces cerevisiae. This sterol auxotroph has been thought to lack the ability to synthesize sterols due both to the absence of 2,3-oxidosqualene cyclase and to a heme deficiency eliminating cytochrome P-450 which is required in demethylation at C-14. However, when the exogenous sterol was 5α-cholestan-3β-ol, 5α-cholest-8(14)-en-3β-ol, or 24β-methyl-5α-cholest-8(14)-en-3β-ol, sterol synthesis was found to proceed yielding 1-3 fg/cell of ergosterol. Ergosterol was identified by mass spectroscopy, gas and high performance liquid chromatography, ultraviolet spectroscopy, and radioactive labelling from [ 3 H]acetate. Except for some cholest-5-en-3β-ol (cholesterol) which was derived from the 5α-cholestan-3β-ol, the stanol and the two 8(14)-stenols were not significantly metabolized confirming the absence of an isomerase for migration of the double bond from C-8(14) to C-7. Drastic reduction of ergosterol synthesis to not more than 0.06 fg/cell was observed when the exogenous sterol either had a double bond at C-5, as in the case of cholesterol, or could be metabolized to a sterol with such a bond. Thus, both 5α-cholest-8(9)-en-3β-ol and 5α-cholest-7-en-3β-ol (lathosterol) were converted to cholesta-5,7-dien-3β-ol (7-dehydrocholesterol), and the presence of the latter dienol depressed the level of ergosterol

  6. Auxotrophic recombinant Mycobacterium bovis BCG overexpressing Ag85B enhances cytotoxicity on superficial bladder cancer cells in vitro.

    Science.gov (United States)

    Begnini, Karine Rech; Rizzi, Caroline; Campos, Vinicius Farias; Borsuk, Sibele; Schultze, Eduarda; Yurgel, Virginia Campello; Nedel, Fernanda; Dellagostin, Odir Antônio; Collares, Tiago; Seixas, Fabiana Kömmling

    2013-02-01

    BCG therapy remains at the forefront of immunotherapy for treating patients with superficial bladder cancer. The high incidence of local side effects and the presence of non-responder diseases have led to efforts to improve the therapy. Hence, we proposed that an auxotrophic recombinant BCG strain overexpressing Ag85B (BCG ∆leuD/Ag85B), could enhance the cytotoxicity to the human bladder carcinoma cell line 5637. The rBCG was generated using an expression plasmid encoding the mycobacterial antigen Ag85B to transform a BCG ∆leuD strain. The inhibitory effect of BCG ∆leuD/Ag85B on 5637 cells was determined by the MTT method, morphology observation and a LIVE/DEAD assay. Gene expression profiles for apoptotic, cell cycle-related and oxidative stress-related genes were investigated by qRT-PCR. Bax, bcl-2 and p53 induction by BCG ∆leuD/Ag85B treatment was evaluated by Western blotting. BCG ∆leuD/Ag85B revealed a superior cytotoxicity effect compared to the control strains used in this study. The results showed that the expression level of pro-apoptotic and cell cycle-related genes increased after BCG ∆leuD/Ag85B treatment, whereas the mRNA levels of anti-apoptotic genes decreased. Interestingly, BCG ∆leuD/Ag85B also increased the mRNA level of antioxidant enzymes in the bladder cancer cell line. Bax and p53 proteins levels increased following treatment. In conclusion, these results suggest that treatment with BCG ∆leuD/Ag85B enhances cytotoxicity for superficial bladder cancer cells in vitro. Therefore, rBCG therapy may have potential benefits in the treatment of bladder cancer.

  7. Use of organic acids to inactivate Escherichia coli O157:H7, Salmonella Typhimurium, and Listeria monocytogenes on organic fresh apples and lettuce.

    Science.gov (United States)

    Park, Sang-Hyun; Choi, Mi-Ran; Park, Jeong-Woong; Park, Ki-Hwan; Chung, Myung-Sub; Ryu, Sangryeol; Kang, Dong-Hyun

    2011-08-01

    This study was undertaken to investigate the antimicrobial effect of organic acids against Escherichia coli O157:H7, Salmonella Typhimurium, and Listeria monocytogenes on whole red organic apples and lettuce. Several studies have been conducted to evaluate organic acids as sanitizers. However, no studies have compared antimicrobial effects of various organic acids on organic fresh produce, including evaluation of color changes of produce. Apples and lettuce were inoculated with a cocktail of 3 strains each of 3 foodborne pathogens provided above and treated with 1% and 2% organic acids (propionic, acetic, lactic, malic, and citric acid) for 0, 0.5, 1, 5, and 10 min. With increasing treatment time and acid concentration, organic acid treatments showed significant reduction compared to the control treatment (distilled water), and differences in antimicrobial effects between organic acids were observed. After 10 min of treatment with 1% and 2% organic acids in apples, propionic (0.92 to 2.75 log reduction), acetic (0.52 to 2.78 log reduction), lactic (1.69 to >3.42 log reduction), malic (1.48 to >3.42 log reduction), and citric acid (1.52 to >3.42 log reduction) exhibited significant (P acid (1.85 to 2.86 log reduction) showed significant (P acids treatment were not significant during storage. It is suggested that organic acids have a potential as sanitizers for organic fresh produce. These data may help the organic produce industry provide safe fresh produce for consumers. © 2011 Institute of Food Technologists®

  8. Salmonella from Baby Turtles

    Centers for Disease Control (CDC) Podcasts

    2017-01-09

    Dr. Stacey Bosch, a veterinarian with CDC, discusses her article on Salmonella infections associated with baby turtles.  Created: 1/9/2017 by National Center for Emerging and Zoonotic Infectious Diseases (NCEZID).   Date Released: 1/9/2017.

  9. Salmonella burden in Lebanon.

    Science.gov (United States)

    Malaeb, M; Bizri, A R; Ghosn, N; Berry, A; Musharrafieh, U

    2016-06-01

    Salmonellosis is a disease that represents a major public health concern in both developing and developed countries. The aim of this article is to evaluate the public health burden of Salmonella illness in Lebanon. The current scope of the Salmonella infection problem was assessed in relation to disease incidence and distribution with respect to age, gender and district. Factors that provide a better understanding of the magnitude of the problem were explored and highlighted. Data reported to the Epidemiologic Surveillance Department at the Lebanese Ministry of Public Health between 2001 and 2013 was reviewed. Information obtained was compared to information reported regionally and globally. The estimated true incidence was derived using multipliers from the CDC and Jordan. A literature review of all published data from Lebanon about Salmonella susceptibility/resistance patterns and its serious clinical complications was conducted. The estimated incidence was 13·34 cases/100 000 individuals, most cases occurred in the 20-39 years age group with no significant gender variation. Poor and less developed districts of Lebanon had the highest number of cases and the peak incidence was in summer. Reflecting on the projected incidence derived from the use of multipliers indicates a major discrepancy between what is reported and what is estimated. We conclude that data about Salmonella infection in Lebanon and many Middle Eastern and developing countries lack crucial information and are not necessarily representative of the true incidence, prevalence and burden of illness.

  10. Radiation-induced mutagenicity and lethality in Ames tester strains of Salmonella

    International Nuclear Information System (INIS)

    Isildar, M.; Bakale, G.

    1984-01-01

    Mutation and killing induced by X radiation and 60 Co γ radiation were studied in six different histidine-requiring auxotrophs of Salmonella typhimurium. Strain TA100, which is sensitive to base-pair substitutions, and strains TA2637 and TA98, which are sensitive to frameshifts, carry the pKM101 plasmid and exhibit significantly higher radiation-induced mutations compared to their plasmidless parent strains TA1535, TA1537, and TA1538, respectively. Among the plasmid-containing strains, TA98 and TA2637 are much more sensitive to the mutagenic action of radiation than is TA100 based on a comparison with their respective spontaneous mutation rates; however, no uniformity was observed in the responses of the strains to the lethal action of ionizing radiation. The following conclusions are consistent with these observations: (1) the standard Ames Salmonella assay correctly identifies ionizing radiation as a mutagenic agent; (2) frameshift-sensitive parent strains are more sensitive to the mutagenic effects of ionizing radiation than is the only strain studied that is sensitive to base-pair substitutions; and (3) enhancement of mutagenesis and survival is related to plasmid-mediated repair of DNA damage induced by ionizing radiation and does not involve damage induced by Cerenkov-generated uv radiation which is negligible for our irradiation conditions

  11. Investigations of multiresistance to antibiotics and chemotherapeutics and extended spectrum beta: Lactamase effect (ESBL test in strains E.coli and salmonella originating from domestic animals

    Directory of Open Access Journals (Sweden)

    Mišić Dušan

    2006-01-01

    Full Text Available The presence of multiresistance to the effects of antibiotics and chemotherapeutics and extended spectrum beta-lactamase were examined in 45 strains of E. coli and 35 strains of Salmonella. The strains of E. coli originated from several species of domestic animals: dogs, cats, poultry, and cattle, and 30 strains of Salmonella originated from poultry, 4 strains from cattle, and 1 strain from swine. The presence of the following serovarieties was established using serological examinations: Salmonella Enteritidis 17 strains, Salmonella Gallinarum 1 strain, Salmonella Hartford 5 strains, Salmonella Anatum 1 strain, Salmonella Typhimurium 4 strains, Salmonella Agona 1 strain, Salmonella Infantis 1 strain, Salmonella Thompson var. Berlin 1 strain, Salmonella Tennessee 1 strain, Salmonella Senftenberg 1 strain, Salmonella Glostrup 1 strain, and Salmonella Hadar 1 strain. In the examinations of the listed strains we used antibiogram discs of ampicillin, amoxicillin with clavulanic acid, cephalexin, cephtriaxon, cephotaxim, cephtazidime, aztreonam, gentamycin, chloramphenicol, tetracycline, cyprofloxacine, and a combination of sulphamethoxasole and trimethoprim. The lowest prevalence of multiresistance in E. Coli strains to 3 or more antibiotics was established in dogs 20%, and the highest in 60% strains originating from swine. In 62.88% strains of Salmonella we established sensitivity to all applied antibiotics. Resistance was also established in a small number of the examined strains to ampicillin (11 strains, to tetracycline (5 strains, to amoxicillin with clavulanic acid (5 strains, to sulphamethoxasole with trimethoprim (5 strains, to gentamycin (3 strains, and to cloramphenicol (1 strain. Of all the examined strains of Salmonella, 6 strains originating from poultry exhibited multiresistence. The presence of extended spectrum beta-lactamase effects examined using the ESBL test, was not established in strains of E. coli and Salmonella strains.

  12. Thermal inactivation of eight Salmonella serotypes on dry corn flour.

    OpenAIRE

    VanCauwenberge, J E; Bothast, R J; Kwolek, W F

    1981-01-01

    Dry heat was used to inactivate Salmonella newington, Salmonella typhimurium, Salmonella anatum, Salmonella kentucky, Salmonella cubana, Salmonella seftenberg, Salmonella thompson, and Salmonella tennessee in corn flour at 10 and 15% moisture. The flour was spray inoculated at 10(5) Salmonella cells per g and then stored at 49 degrees C (120 degrees F); viable Salmonella cells were counted on Trypticase (BBL Microbiology Systems) soy agar plates every 30 min for the first 4 h and then at 4-h ...

  13. Prevalence and antibiotic resistance of Salmonella spp. in meat products, meat preparations and minced meat

    Science.gov (United States)

    Rašeta, M.; Mrdović, B.; Janković, V.; Bečkei, Z.; Lakićević, B.; Vidanović, D.; Polaček, V.

    2017-09-01

    This study aimed to determine Salmonella spp. prevalence in meat products, meat preparations and minced meat. Over a period of three years, a total of 300 samples were taken (100 RTE meat products, 100 meat preparations and 100 minced meat) and examined for the presence of Salmonella spp. Sampling was carried out at the warehouses of the food manufacturers. Salmonella spp. were not detected in RTE meat products, while 7% of semi-finished meat products (fresh sausages, grill meat formed and unformed) contained Salmonella, as did 18% of minced meats (minced pork II category, minced beef II category, mixed minced meat). The 25 Salmonella isolates obtained were examined for antibiotic resistance by the disk diffusion test, according to the NCCLS and CLSI guidelines. Isolates showed resistance to ampicillin and nalidixic acid (80%), tetracycline (72%), cefotaxime/clavulanic acid (48%), but not to gentamicin (8%) or trimethoprim/sulfamethoxazole (0%).

  14. Mutations of the Corynebacterium glutamicum NCgl1221 Gene, Encoding a Mechanosensitive Channel Homolog, Induce l-Glutamic Acid Production▿

    OpenAIRE

    Nakamura, Jun; Hirano, Seiko; Ito, Hisao; Wachi, Masaaki

    2007-01-01

    Corynebacterium glutamicum is a biotin auxotroph that secretes l-glutamic acid in response to biotin limitation; this process is employed in industrial l-glutamic acid production. Fatty acid ester surfactants and penicillin also induce l-glutamic acid secretion, even in the presence of biotin. However, the mechanism of l-glutamic acid secretion remains unclear. It was recently reported that disruption of odhA, encoding a subunit of the 2-oxoglutarate dehydrogenase complex, resulted in l-gluta...

  15. Uptake and Metabolism of Antibiotics Roseoflavin and 8-Demethyl-8-Aminoriboflavin in Riboflavin-Auxotrophic Listeria monocytogenes.

    Science.gov (United States)

    Matern, Andreas; Pedrolli, Danielle; Großhennig, Stephanie; Johansson, Jörgen; Mack, Matthias

    2016-12-01

    The riboflavin analogs roseoflavin (RoF) and 8-demethyl-8-aminoriboflavin (AF) are produced by the bacteria Streptomyces davawensis and Streptomyces cinnabarinus Riboflavin analogs have the potential to be used as broad-spectrum antibiotics, and we therefore studied the metabolism of riboflavin (vitamin B 2 ), RoF, and AF in the human pathogen Listeria monocytogenes, a bacterium which is a riboflavin auxotroph. We show that the L. monocytogenes protein Lmo1945 is responsible for the uptake of riboflavin, RoF, and AF. Following import, these flavins are phosphorylated/adenylylated by the bifunctional flavokinase/flavin adenine dinucleotide (FAD) synthetase Lmo1329 and adenylylated by the unique FAD synthetase Lmo0728, the first monofunctional FAD synthetase to be described in bacteria. Lmo1329 generates the cofactors flavin mononucleotide (FMN) and FAD, whereas Lmo0728 produces FAD only. The combined activities of Lmo1329 and Lmo0728 are responsible for the intracellular formation of the toxic cofactor analogs roseoflavin mononucleotide (RoFMN), roseoflavin adenine dinucleotide (RoFAD), 8-demethyl-8-aminoriboflavin mononucleotide (AFMN), and 8-demethyl-8-aminoriboflavin adenine dinucleotide (AFAD). In vivo reporter gene assays and in vitro transcription/translation experiments show that the L. monocytogenes FMN riboswitch Rli96, which controls expression of the riboflavin transport gene lmo1945, is negatively affected by riboflavin/FMN and RoF/RoFMN but not by AF/AFMN. Treatment of L. monocytogenes with RoF or AF leads to drastically reduced FMN/FAD levels. We suggest that the reduced flavin cofactor levels in combination with concomitant synthesis of inactive cofactor analogs (RoFMN, RoFAD, AFMN, and AFAD) explain why RoF and AF contribute to antibiotic activity in L. monocytogenes IMPORTANCE: The riboflavin analogs roseoflavin (RoF) and 8-demethyl-8-aminoriboflavin (AF) are small molecules which are produced by Streptomyces davawensis and Streptomyces cinnabarinus

  16. Prevalence and antimicrobial resistance pattern of Salmonella in animal feed produced in Namibia.

    Science.gov (United States)

    Shilangale, Renatus P; Di Giannatale, Elisabetta; Chimwamurombe, Percy M; Kaaya, Godwin P

    2012-01-01

    The occurrence of Salmonella is a global challenge in the public health and food production sectors. Our study investigated the prevalence, serovar and antimicrobial susceptibility of strains of Salmonella serovars isolated from animal feed (meat-and-bone and blood meal) samples from two commercial abattoirs in Namibia. A total of 650 samples (n=650) were examined for the presence of Salmonella. Results showed that 10.9% (n=71) were positive for Salmonella. Of the Salmonella serovars isolated, S. Chester was the most commonly isolated serovar (19.7%), followed by S. Schwarzengrund at 12.7%. From the Salmonella isolates, 19.7% (n=14) were resistant to one or more of the antimicrobials (nalidixic acid, trimethoprim-sulfamethoxazole, sulfisoxazole, streptomycin and/or tetracycline), whereas 80.3% (n=57) were susceptible to all 16 antimicrobials tested. Resistance to sulfisoxazole and the trimethroprimsuflamethoxazole combination were the most common. The resistant isolates belonged to ten different Salmonella serovars. The susceptibility of most of the Salmonella isolated to the antimicrobials tested indicates that anti-microbial resistance is not as common and extensive in Namibia as has been reported in many other countries. It also appears that there is a range of antimicrobials available that are effective in managing Salmonella infections in Namibia. However, there is some evidence that resistance is developing and this will need further monitoring to ensure it does not become a problem.

  17. Controle da infecção por Salmonella Enteritidis em frangos de corte com ácidos orgânicos e mananoligossacarídeo Control of the infection caused by Salmonella Enteritidis with organic acids and mannanoligosaccharide in broiler

    Directory of Open Access Journals (Sweden)

    Joana Darc Lopes Bassan

    2008-10-01

    Full Text Available O objetivo deste estudo foi avaliar a ação de dois ácidos orgânicos (ácido fórmico e ácido propiônico e de um mananoligossacarídeo (MOS adicionados à dieta no controle da infecção intestinal por Salmonella Enteritidis (SE em frangos de corte. Neste estudo de 39 dias, foram utilizadas 150 aves, de um dia de idade, da linhagem Cobb, lote misto, livre de SE, divididas em seis tratamentos (T com 25 animais cada, em que: T1 (ausência de infecção, T2 (ácidos orgânicos e ausência de infecção, T3 (ácidos orgânicos + MOS e ausência de infecção, T4 (ácidos orgânicos e infecção com SE, T5 (ácidos orgânicos + MOS e infecção com SE e T6 (infecção com SE. No 4° dia após o alojamento, a cama foi instilada com SE e a cada sete dias cinco aves por grupo foram submetidas à eutanásia por deslocamento cervical e necropsiadas. Depois foram realizados exames bacteriológicos para SE nesses animais, utilizando fezes coletadas sobre a cama de maravalha dos grupos e das tonsilas cecais dos animais necropsiados. No 18° dia, somente 60% das aves estavam infectadas nos tratamentos T4 e T5; no 25° dia, 40% das aves no T4 e 20% no T5 estavam infectadas; no 32° dia 100% das amostras testadas foram negativas em ambos os tratamentos (T4 e T5. Constatou-se que o T6 foi 100% positivo até o 32° dia e no 39° dia reduziu em 20% o número de animais infectados. Dentro dos parâmetros de avaliação deste experimento, os ácidos orgânicos e o mananoligossacarídeo adicionados à dieta contribuíram para o controle da infecção por SE.The objective of this study was to evaluate the effect of two organic acids (formic acid and propionic acid and of one mannanoligosaccharide added to the diet to control the intestinal infection caused by Salmonella Enteritidis (SE in broilers. In this study of 39 days 150 birds were used, with one day of age, of the Cobb lineage, both sexes and free of SE. They were divided in 6 different treatments (T with

  18. Ten years of antimicrobial susceptibility testing of Salmonella from Danish pig farms

    DEFF Research Database (Denmark)

    Emborg, Hanne-Dorthe; Baggesen, Dorte Lau; Aarestrup, Frank Møller

    2008-01-01

    to the following antimicrobials were determined: ampicillin, chloramphenicol, gentamicin, nalidixic acid, colistin, streptomycin, sulphonamide, tetracycline and trimethoprim. Results: No significant development of resistance occurred within the most important serovars, except Salmonella Typhimurium. A major...

  19. The construction and use of versatile binary vectors carrying pyrG auxotrophic marker and fluorescent reporter genes for Agrobacterium-mediated transformation of Aspergillus oryzae.

    Science.gov (United States)

    Nguyen, Khuyen Thi; Ho, Quynh Ngoc; Pham, Thu Ha; Phan, Tuan-Nghia; Tran, Van-Tuan

    2016-12-01

    Aspergillus oryzae is a safe mold widely used in food industry. It is also considered as a microbial cell factory for production of recombinant proteins and enzymes. Currently, genetic manipulation of filamentous fungi is achieved via Agrobacterium tumefaciens-mediated transformation methods usually employing antibiotic resistance markers. These methods are hardly usable for A. oryzae due to its strong resistance to the common antifungal compounds used for fungal transformation. In this study, we have constructed two binary vectors carrying the pyrG gene from A. oryzae as a biochemical marker than an antibiotic resistance marker, and an expression cassette for GFP or DsRed reporter gene under control of the constitutive gpdA promoter from Aspergillus nidulans. All components of these vectors are changeable to generate new versions for specific research purposes. The developed vectors are fully functional for heterologous expression of the GFP and DsRed fluorescent proteins in the uridine/uracil auxotrophic A. oryzae strain. Our study provides a new approach for A. oryzae transformation using pyrG as the selectable auxotrophic marker, A. tumefaciens as the DNA transfer tool and fungal spores as the transformation material. The binary vectors constructed can be used for gene expression studies in this industrially important filamentous fungus.

  20. Phenotypic and Genotypic Features of a Salmonella Heidelberg Strain Isolated in Broilers in Brazil and Their Possible Association to Antibiotics and Short-Chain Organic Acids Resistance and Susceptibility.

    Science.gov (United States)

    Santin, Elizabeth; Hayashi, Ricardo Mitsuo; Wammes, Jessica Caroline; Gonzalez-Esquerra, Ricardo; Carazzolle, Marcelo Falsarella; Freire, Caio César de Melo; Monzani, Paulo Sérgio; da Cunha, Anderson Ferreira

    2017-01-01

    Salmonella enterica serovar Heidelberg is a human pathogen also found in broilers. A strain (UFPR1) has been associated with field reports of resistance to short-chain organic acids (SCOA) in broilers in the South of Brazil, but was susceptible to a Bacillus subtilis -based probiotic added in feed in a related study. This work aimed to (i) report clinical symptoms caused by SH UFPR1 in broilers, (ii) study its susceptibility to some antibiotics in vitro , and (iii) SCOA in vivo ; and (iv) relate these phenotypic observations with its genome characteristics. Two in vivo trials used 1-day-old chicks housed for 21 days in 8 sterilized isolated negative pressure rooms with 4 battery cages of 12 birds each. Birds were challenged or not with 10 7  CFU/bird of SH UFPR1 orally and exposed or not to SCOA in a 2 × 2 factorial design. Zootechnical parameters were unaffected ( P  > 0.05), no clinical signs were observed, and few cecal and hepatic histologic and immune-related alterations were seen, in birds challenged with SH. Formic and propionic acids added together in drinking water, fumaric and benzoic acid in feed (Trial 1), and coated calcium butyrate in feed (Trial 2) did not reduce the SH isolation frequencies seen in cecum and liver in broilers after SH challenge ( P  > 0.05). SH UFPR1 was susceptible to amikacin, amoxicillin + clavulanate, ceftiofur, cephalexin, doxycycline and oxytetracycline; and mildly susceptible to ampicillin + sulbactam, cephalothin, ciprofloxacin, enrofloxacin, and gentamycin in an in vitro minimum inhibitory concentration model using Mueller-Hinton agar. The whole genome of SH UFPR1 was sequenced and consisted of a circular chromosome, spanning 4,760,321 bp with 52.18% of GC-content encoding 84 tRNA, 22 rRNA, and 4,427 protein-coding genes. The comparison between SH UFPR1 genome and a multidrug-resistant SL476 strain revealed 11 missing genomic fragments and 5 insertions related to bgt, bgr , and rpoS genes. The

  1. Phenotypic and Genotypic Features of a Salmonella Heidelberg Strain Isolated in Broilers in Brazil and Their Possible Association to Antibiotics and Short-Chain Organic Acids Resistance and Susceptibility

    Directory of Open Access Journals (Sweden)

    Elizabeth Santin

    2017-11-01

    Full Text Available Salmonella enterica serovar Heidelberg is a human pathogen also found in broilers. A strain (UFPR1 has been associated with field reports of resistance to short-chain organic acids (SCOA in broilers in the South of Brazil, but was susceptible to a Bacillus subtilis-based probiotic added in feed in a related study. This work aimed to (i report clinical symptoms caused by SH UFPR1 in broilers, (ii study its susceptibility to some antibiotics in vitro, and (iii SCOA in vivo; and (iv relate these phenotypic observations with its genome characteristics. Two in vivo trials used 1-day-old chicks housed for 21 days in 8 sterilized isolated negative pressure rooms with 4 battery cages of 12 birds each. Birds were challenged or not with 107 CFU/bird of SH UFPR1 orally and exposed or not to SCOA in a 2 × 2 factorial design. Zootechnical parameters were unaffected (P > 0.05, no clinical signs were observed, and few cecal and hepatic histologic and immune-related alterations were seen, in birds challenged with SH. Formic and propionic acids added together in drinking water, fumaric and benzoic acid in feed (Trial 1, and coated calcium butyrate in feed (Trial 2 did not reduce the SH isolation frequencies seen in cecum and liver in broilers after SH challenge (P > 0.05. SH UFPR1 was susceptible to amikacin, amoxicillin + clavulanate, ceftiofur, cephalexin, doxycycline and oxytetracycline; and mildly susceptible to ampicillin + sulbactam, cephalothin, ciprofloxacin, enrofloxacin, and gentamycin in an in vitro minimum inhibitory concentration model using Mueller–Hinton agar. The whole genome of SH UFPR1 was sequenced and consisted of a circular chromosome, spanning 4,760,321 bp with 52.18% of GC-content encoding 84 tRNA, 22 rRNA, and 4,427 protein-coding genes. The comparison between SH UFPR1 genome and a multidrug-resistant SL476 strain revealed 11 missing genomic fragments and 5 insertions related to bgt, bgr, and rpoS genes. The

  2. Cinnamaldehyde, Carvacrol and Organic Acids Affect Gene Expression of Selected Oxidative Stress and Inflammation Markers in IPEC-J2 Cells Exposed to Salmonella typhimurium

    NARCIS (Netherlands)

    Burt, Sara A; Adolfse, Simone J M; Ahad, Dina S A; Tersteeg-Zijderveld, Monique H G; Jongerius-Gortemaker, Betty G M; Post, Jan A; Brüggemann, Holger; Santos, Regiane R

    2016-01-01

    Essential oils and organic acids are used as feed additives to improve health status and reduce colonization with pathogens. Although bactericidal in vitro, concentrations achieved in the animal gut are probably not lethal to pathogens. The aim of this study was to investigate the effects of

  3. Transcriptional analysis of porcine intestinal mucosa infected with Salmonella Typhimurium revealed a massive inflammatory response and disruption of bile acid absorption in ileum

    DEFF Research Database (Denmark)

    Uribe, Juber Herrera; Collado-Romero, Melania; Zaldívar-López, Sara

    2016-01-01

    -regulated genes of the FXR pathway (e.g., NR1H4, FABP6, APOA1, SLC10A2), indicating disruption of the bile acid absorption in ileum. This result was confirmed by decreased high-density lipoprotein cholesterol in serum of infected pigs. Ileal inflammatory gene expression changes peaked at 2 dpi and tended...

  4. The inhibitory effect of bovine rumen fluid on Salmonella typhimurium.

    Science.gov (United States)

    Chambers, P G; Lysons, R J

    1979-05-01

    The possible fate of Salmonella typhimurium in the rumen was investigated by monitoring rumen volatile fatty acids (VFA), lactate concentrations and pH over periods which included regular feeding and 48 h starvation. Preparations were made containing 50 per cent rumen fluid from the cow or VFA solutions, and then inoculated with S typhimurium. Viable counts before and after incubation for 24 h at 37 degrees C were compared. Incubation in broths with high concentrations of VFA and low pH resulted in a marked decrease in salmonella numbers, while lower VFA concentrations had little or no inhibitory effect on growth.

  5. A Perspective on Invasive Salmonella Disease in Africa.

    Science.gov (United States)

    Crump, John A; Heyderman, Robert S

    2015-11-01

    Salmonella enterica is a leading cause of community-acquired bloodstream infection in Africa. The contribution of typhoidal and nontyphoidal Salmonella serovars to invasive disease varies considerably in place and time, even within the same country. Nonetheless, many African countries are now thought to experience typhoid fever incidence >100 per 100,000 per year with approximately 1% of patients dying. Invasive nontyphoidal Salmonella (iNTS) disease was estimated to cause 3.4 million illnesses and 681 316 deaths in 2010, with the most disease in Africa. Antimicrobial drug resistance is a growing problem in S. enterica that threatens to further compromise patient outcomes. Reservoirs for nontyphoidal Salmonella and the predominant routes of transmission for typhoidal and nontyphoidal Salmonella are not well understood in Africa, hampering the design of evidence-based, non-vaccine- and vaccine-based prevention measures. It is difficult to distinguish clinically invasive Salmonella disease from febrile illnesses caused by other pathogens. Blood cultures are the mainstay of laboratory diagnosis, but lack sensitivity due to the low magnitude of bacteremia, do not produce results at point of care, and are not widely available in Africa. Serologic approaches to diagnosis remain inaccurate, and nucleic acid amplification tests are also compromised by low concentrations of bacteria. High-throughput whole-genome sequencing, together with a range of novel analytic pipelines, has provided new insights into the complex pattern of epidemiology, pathogenesis, and host adaptation. Concerted efforts are therefore needed to apply these new tools in the context of high-quality field surveillance to improve diagnosis, patient management, control, and prevention of invasive Salmonella infections in Africa. © The Author 2015. Published by Oxford University Press on behalf of the Infectious Diseases Society of America. All rights reserved. For Permissions, please e-mail: journals.permissions@oup.com.

  6. Performance of the auxotrophic Saccharomyces cerevisiae BY4741 as host for the production of IL-1β in aerated fed-batch reactor: role of ACA supplementation, strain viability, and maintenance energy

    Directory of Open Access Journals (Sweden)

    Zueco Jesus

    2009-12-01

    Full Text Available Abstract Background Saccharomyces cerevisiae BY4741 is an auxotrophic commonly used strain. In this work it has been used as host for the expression and secretion of human interleukin-1β (IL1β, using the cell wall protein Pir4 as fusion partner. To achieve high cell density and, consequently, high product yield, BY4741 [PIR4-IL1β] was cultured in an aerated fed-batch reactor, using a defined mineral medium supplemented with casamino acids as ACA (auxotrophy-complementing amino acid source. Also the S. cerevisiae mutant BY4741 Δyca1 [PIR4-IL1β], carrying the deletion of the YCA1 gene coding for a caspase-like protein involved in the apoptotic response, was cultured in aerated fed-batch reactor and compared to the parental strain, to test the effect of this mutation on strain robustness. Viability of the producer strains was examined during the runs and a mathematical model, which took into consideration the viable biomass present in the reactor and the glucose consumption for both growth and maintenance, was developed to describe and explain the time-course evolution of the process for both, the BY4741 parental and the BY4741 Δyca1 mutant strain. Results Our results show that the concentrations of ACA in the feeding solution, corresponding to those routinely used in the literature, are limiting for the growth of S. cerevisiae BY4741 [PIR4-IL1β] in fed-batch reactor. Even in the presence of a proper ACA supplementation, S. cerevisiae BY4741 [PIR4-IL1β] did not achieve a high cell density. The Δyca1 deletion did not have a beneficial effect on the overall performance of the strain, but it had a clear effect on its viability, which was not impaired during fed-batch operations, as shown by the kd value (0.0045 h-1, negligible if compared to that of the parental strain (0.028 h-1. However, independently of their robustness, both the parental and the Δyca1 mutant ceased to grow early during fed-batch runs, both strains using most of the

  7. Prevalence of Salmonella in Australian reptiles.

    Science.gov (United States)

    Scheelings, T Franciscus; Lightfoot, Dianne; Holz, Peter

    2011-01-01

    From January 2007 until June 2008, 504 reptiles of four families and 57 species were examined for Salmonella by using cloacal or intestinal swabs. Salmonella was identified in 139 (28%) of the 504 animals tested. Of the 504 reptiles examined, 210 were captive and 294 were wild. Ninety-eight (47%) of the captive reptiles were shedding Salmonella at the time of sampling. In contrast, only 41 (14%) of the wild reptiles were shedding Salmonella. The higher prevalence of Salmonella in captive reptiles was statistically significant (Preptiles in Australia are not natural carriers of Salmonella and that diet and captivity may influence Salmonella excretion in other species.

  8. Prevalence, Virulence Genes and Antimicrobial Resistance Profiles of Salmonella Serovars from Retail Beef in Selangor, Malaysia

    Directory of Open Access Journals (Sweden)

    Tze Y. Thung

    2018-01-01

    Full Text Available The aim of the present study was to investigate the prevalence of Salmonella spp., Salmonella Enteritidis and Salmonella Typhimurium in retail beef from different retail markets of Selangor area, as well as, to assess their pathogenic potential and antimicrobial resistance. A total of 240 retail beef meat samples (chuck = 60; rib = 60; round = 60; sirloin = 60 were randomly collected. The multiplex polymerase chain reaction (mPCR in combination with the most probable number (MPN method was employed to detect Salmonella spp., S. Enteritidis and S. Typhimurium in the meat samples. The prevalence of Salmonella spp., S. Enteritidis and S. Typhimurium in 240 beef meat samples were 7.50, 1.25, and 0.83%, respectively. The microbial loads of total Salmonella was found in the range of <3 to 15 MPN/g. Eight different serovars of Salmonella were identified among the 23 isolates, and S. Agona was the predominant serovar (26.09%. Interestingly, all the Salmonella isolates were resistant to penicillin, erythromycin and vancomycin, but the sensitivity was observed for tetracycline, gentamicin and amoxicillin/clavulanic acid. All 23 isolates were resistant to at least three antibiotics. Two S. Typhimurium isolates (8.70% exhibited the highest multiple antibiotic resistance (MAR index value of 0.56 which shown resistance to nine antibiotics. PCR analysis of virulence genes showed that all Salmonella isolates (100% were positive for the invA gene. Meanwhile, pefA was only identified in S. Enteritidis and S. Typhimurium. The findings in this study indicate that retail beef products tested were widely contaminated with multi-drug resistant (MDR Salmonella and various virulence genes are present among the isolated Salmonella serovars.

  9. Antibiotic Resistant Salmonella and Vibrio Associated with Farmed Litopenaeus vannamei

    Directory of Open Access Journals (Sweden)

    Sanjoy Banerjee

    2012-01-01

    Full Text Available Salmonella and Vibrio species were isolated and identified from Litopenaeus vannamei cultured in shrimp farms. Shrimp samples showed occurrence of 3.3% of Salmonella and 48.3% of Vibrio. The isolates were also screened for antibiotic resistance to oxolinic acid, sulphonamides, tetracycline, sulfamethoxazole/trimethoprim, norfloxacin, ampicillin, doxycycline hydrochloride, erythromycin, chloramphenicol, and nitrofurantoin. Salmonella enterica serovar Corvallis isolated from shrimp showed individual and multiple antibiotic resistance patterns. Five Vibrio species having individual and multiple antibiotic resistance were also identified. They were Vibrio cholerae (18.3%, V. mimicus (16.7%, V. parahaemolyticus (10%, V. vulnificus (6.7%, and V. alginolyticus (1.7%. Farm owners should be concerned about the presence of these pathogenic bacteria which also contributes to human health risk and should adopt best management practices for responsible aquaculture to ensure the quality of shrimp.

  10. Salmonella, Shigella, and Yersinia

    Science.gov (United States)

    Dekker, John; Frank, Karen

    2015-01-01

    Synopsis Salmonella, Shigella, and Yersinia cause a well-characterized spectrum of disease in humans, ranging from asymptomatic carriage to hemorrhagic colitis and fatal typhoidal fever. These pathogens are responsible for millions of cases of food-borne illness in the U.S. each year, with substantial costs measured in hospitalizations and lost productivity. In the developing world, illness caused by these pathogens is not only more prevalent, but is also associated with a greater case-fatality rate. Classical methods for identification rely on selective media and serology, but newer methods based on mass spectrometry and PCR show great promise for routine clinical testing. PMID:26004640

  11. Eleventh CRL-Salmonella interlaboratory comparison study on typing of Salmonella spp.

    NARCIS (Netherlands)

    Berk PA; Maas HME; de Pinna E; Mooijman KA; MGB

    2006-01-01

    Het elfde ringonderzoek voor de typering van Salmonella werd in maart 2006 georganiseerd door het Communautair Referentie Laboratorium voor Salmonella (CRL-Salmonella, Bilthoven, Nederland) in samenwerking met de Health Protection Agency (HPA, Londen, Verenigd Koninkrijk). 26 Nationale Referentie

  12. Tenth CRL-Salmonella interlaboratory comparison study on typing of Salmonella spp.

    NARCIS (Netherlands)

    Korver H; Maas HME; Ward LR; Mevius DJ; Mooijman KA; MGB

    2006-01-01

    Het tiende ringonderzoek voor de typering van Salmonella werd in maart 2005 georganiseerd door het Communautair Referentie Laboratorium voor Salmonella (CRL-Salmonella, Bilthoven, Nederland) in samenwerking met de Health Protection Agency (HPA, Londen, Verenigd Koninkrijk) en het Centraal Instituut

  13. Interactions of Salmonella enterica Serovar Typhimurium and Pectobacterium carotovorum within a Tomato Soft Rot.

    Science.gov (United States)

    George, Andrée S; Cox, Clayton E; Desai, Prerak; Porwollik, Steffen; Chu, Weiping; de Moraes, Marcos H; McClelland, Michael; Brandl, Maria T; Teplitski, Max

    2018-03-01

    Salmonella spp. are remarkably adaptable pathogens, and this adaptability allows these bacteria to thrive in a variety of environments and hosts. The mechanisms with which these pathogens establish within a niche amid the native microbiota remain poorly understood. Here, we aimed to uncover the mechanisms that enable Salmonella enterica serovar Typhimurium strain ATCC 14028 to benefit from the degradation of plant tissue by a soft rot plant pathogen, Pectobacterium carotovorum The hypothesis that in the soft rot, the liberation of starch (not utilized by P. carotovorum ) makes this polymer available to Salmonella spp., thus allowing it to colonize soft rots, was tested first and proven null. To identify the functions involved in Salmonella soft rot colonization, we carried out transposon insertion sequencing coupled with the phenotypic characterization of the mutants. The data indicate that Salmonella spp. experience a metabolic shift in response to the changes in the environment brought on by Pectobacterium spp. and likely coordinated by the csrBC small regulatory RNA. While csrBC and flhD appear to be of importance in the soft rot, the global two-component system encoded by barA sirA (which controls csrBC and flhDC under laboratory conditions) does not appear to be necessary for the observed phenotype. Motility and the synthesis of nucleotides and amino acids play critical roles in the growth of Salmonella spp. in the soft rot. IMPORTANCE Outbreaks of produce-associated illness continue to be a food safety concern. Earlier studies demonstrated that the presence of phytopathogens on produce was a significant risk factor associated with increased Salmonella carriage on fruits and vegetables. Here, we genetically characterize some of the requirements for interactions between Salmonella and phytobacteria that allow Salmonella spp. to establish a niche within an alternate host (tomato). Pathways necessary for nucleotide synthesis, amino acid synthesis, and motility

  14. Salmonella Persistence in Tomatoes Requires a Distinct Set of Metabolic Functions Identified by Transposon Insertion Sequencing

    Science.gov (United States)

    Desai, Prerak; Porwollik, Steffen; Canals, Rocio; Perez, Daniel R.; Chu, Weiping; McClelland, Michael; Teplitski, Max

    2016-01-01

    ABSTRACT Human enteric pathogens, such as Salmonella spp. and verotoxigenic Escherichia coli, are increasingly recognized as causes of gastroenteritis outbreaks associated with the consumption of fruits and vegetables. Persistence in plants represents an important part of the life cycle of these pathogens. The identification of the full complement of Salmonella genes involved in the colonization of the model plant (tomato) was carried out using transposon insertion sequencing analysis. With this approach, 230,000 transposon insertions were screened in tomato pericarps to identify loci with reduction in fitness, followed by validation of the screen results using competition assays of the isogenic mutants against the wild type. A comparison with studies in animals revealed a distinct plant-associated set of genes, which only partially overlaps with the genes required to elicit disease in animals. De novo biosynthesis of amino acids was critical to persistence within tomatoes, while amino acid scavenging was prevalent in animal infections. Fitness reduction of the Salmonella amino acid synthesis mutants was generally more severe in the tomato rin mutant, which hyperaccumulates certain amino acids, suggesting that these nutrients remain unavailable to Salmonella spp. within plants. Salmonella lipopolysaccharide (LPS) was required for persistence in both animals and plants, exemplifying some shared pathogenesis-related mechanisms in animal and plant hosts. Similarly to phytopathogens, Salmonella spp. required biosynthesis of amino acids, LPS, and nucleotides to colonize tomatoes. Overall, however, it appears that while Salmonella shares some strategies with phytopathogens and taps into its animal virulence-related functions, colonization of tomatoes represents a distinct strategy, highlighting this pathogen's flexible metabolism. IMPORTANCE Outbreaks of gastroenteritis caused by human pathogens have been increasingly associated with foods of plant origin, with tomatoes

  15. Development and applications of Bacillus subtilis test systems for mutagens, involving DNA-repair deficiency and suppressible auxotrophic mutations

    International Nuclear Information System (INIS)

    Tanooka, H.

    1977-01-01

    A mutagen-tester of Bacillus subtilis was constructed and tested with known carcinogens. The parental strain HA101 of Okubo and Yanagida carrying suppressible nonsense mutations in his and met genes was transformed to carry an excision-repair deficiency mutation. The constructed strain TKJ5211 showed a 20-30-fold higher sensitivity for His + reversion than the parental strain when treated with UV and UV-mimetic chemicals but unchanged mutation frequency with X-rays and methyl methanesulfonate. The tester strain was used in a spot test of 30 selected chemicals and also for testing with liver homogenate activation. The results showed an almost equivalent but somewhat broader detection spectrum than the Salmonella typhimurium TA100 system. Another test method used a pair of B. subtilis strains differing in their DNA-repair capacity, i.e. the most UV-sensitive mutant HJ-15 and a wild-type strain, to detect repair-dependent DNA damage produced by chemicals. Spores could be used in either test

  16. Salmonella Control Programs in Denmark

    DEFF Research Database (Denmark)

    Wegener, Henrik Caspar; Hald, Tine; Wong, Danilo Lo Fo

    2003-01-01

    We describe Salmonella control programs of broiler chickens, layer hens, and pigs in Denmark. Major reductions in the incidence of foodborne human salmonellosis have occurred by integrated control of farms and food processing plants. Disease control has been achieved by monitoring the herds...... and flocks, eliminating infected animals, and diversifying animals (animals and products are processed differently depending on Salmonella status) and animal food products according to the determined risk. In 2001, the Danish society saved U.S.$25.5 million by controlling Salmonella. The total annual...... Salmonella control costs in year 2001 were U.S.$14.1 million (U.S.$0.075/kg of pork and U.S.$0.02/kg of broiler or egg). These costs are paid almost exclusively by the industry. The control principles described are applicable to most industrialized countries with modern intensive farming systems....

  17. Kinetics of catalyzed hydrolysis of 4-methylumbelliferyl caprylate (MUCAP) salmonella reagent

    Science.gov (United States)

    Al-Kady, Ahmed S.; Ahmed, El-Sadat I.; Gaber, M.; Hussein, Mohamed M.; Ebeid, El-Zeiny M.

    2011-09-01

    The kinetics of chemical hydrolysis including neutral, acid- and base-catalyzed hydrolysis of 4-methylumbelliferyl caprylate (MUCAP) salmonella reagent were studied at different temperatures. The rate constants and activation parameters were determined by following the build-up of fluorescence peak of the hydrolysis product 4-methylumbelliferone (4-MU). The time scale of esterase enzyme hydrolysis caused by salmonella was compared with chemical hydrolysis as a background process.

  18. Sublethal exposure to commercial formulations of the herbicides dicamba, 2,4-dichlorophenoxyacetic acid, and glyphosate cause changes in antibiotic susceptibility in Escherichia coli and Salmonella enterica serovar Typhimurium.

    Science.gov (United States)

    Kurenbach, Brigitta; Marjoshi, Delphine; Amábile-Cuevas, Carlos F; Ferguson, Gayle C; Godsoe, William; Gibson, Paddy; Heinemann, Jack A

    2015-03-24

    Biocides, such as herbicides, are routinely tested for toxicity but not for sublethal effects on microbes. Many biocides are known to induce an adaptive multiple-antibiotic resistance phenotype. This can be due to either an increase in the expression of efflux pumps, a reduced synthesis of outer membrane porins, or both. Exposures of Escherichia coli and Salmonella enterica serovar Typhimurium to commercial formulations of three herbicides-dicamba (Kamba), 2,4-dichlorophenoxyacetic acid (2,4-D), and glyphosate (Roundup)-were found to induce a changed response to antibiotics. Killing curves in the presence and absence of sublethal herbicide concentrations showed that the directions and the magnitudes of responses varied by herbicide, antibiotic, and species. When induced, MICs of antibiotics of five different classes changed up to 6-fold. In some cases the MIC increased, and in others it decreased. Herbicide concentrations needed to invoke the maximal response were above current food maximum residue levels but within application levels for all herbicides. Compounds that could cause induction had additive effects in combination. The role of soxS, an inducer of the AcrAB efflux pump, was tested in β-galactosidase assays with soxS-lacZ fusion strains of E. coli. Dicamba was a moderate inducer of the sox regulon. Growth assays with Phe-Arg β-naphtylamide (PAβN), an efflux pump inhibitor, confirmed a significant role of efflux in the increased tolerance of E. coli to chloramphenicol in the presence of dicamba and to kanamycin in the presence of glyphosate. Pathways of exposure with relevance to the health of humans, domestic animals, and critical insects are discussed. Increasingly common chemicals used in agriculture, domestic gardens, and public places can induce a multiple-antibiotic resistance phenotype in potential pathogens. The effect occurs upon simultaneous exposure to antibiotics and is faster than the lethal effect of antibiotics. The magnitude of the

  19. Inactivation of Salmonella spp. on tomatoes by plant molecules.

    Science.gov (United States)

    Mattson, Tyler E; Johny, Anup Kollanoor; Amalaradjou, Mary Anne Roshni; More, Karen; Schreiber, David T; Patel, Jitu; Venkitanarayanan, Kumar

    2011-01-05

    The efficacy of carvacrol (CAR), trans-cinnamaldehyde (TC), eugenol (EUG) and β-resorcylic acid (BR) as a wash treatment for reducing Salmonella spp. on tomatoes was investigated. Plum tomatoes inoculated with a six-serotype mixture of Salmonella (10⁸CFU) were subjected to washing in sterile deionized water (control) or deionized water containing chlorine (100 ppm), CAR (0.25 and 0.75%), TC (0.5 and 0.75%), EUG (0.25 and 0.75%), or BR (0.75 and 1.0%) for 15 sec, 1 min, and 3 min. The plant molecules were more effective (Pwashing in water and chlorine. Both concentrations of CAR and TC, and 0.75% EUG decreased Salmonella counts on tomatoes by~6.0 log CFU/ml at 1 min. Both concentrations of BR decreased the pathogen on tomatoes to undetectable levels at 3 min of exposure. Washing of tomatoes in deionized water and chlorine for 3 min reduced Salmonella by ca. 2.0 and 4.0 log CFU/ml, respectively. No Salmonella was detected in the wash water containing the plant molecules or chlorine, whereas a substantial population of the pathogen survived in the control wash water. Moreover, none of the dipping treatments had any effect on the red color of tomatoes (P>0.05). Results indicate that CAR, TC, EUG and BR could effectively be used to kill Salmonella on tomatoes, but additional studies on sensory and quality characteristics of tomatoes treated with plant molecules are warranted. Copyright © 2010 Elsevier B.V. All rights reserved.

  20. Repression of Salmonella enterica phoP Expression by Small Molecules from Physiological Bile

    Science.gov (United States)

    Antunes, L. Caetano M.; Wang, Melody; Andersen, Sarah K.; Ferreira, Rosana B. R.; Kappelhoff, Reinhild; Han, Jun; Borchers, Christoph H.

    2012-01-01

    Infection with Salmonella enterica serovar Typhi in humans causes the life-threatening disease typhoid fever. In the laboratory, typhoid fever can be modeled through the inoculation of susceptible mice with Salmonella enterica serovar Typhimurium. Using this murine model, we previously characterized the interactions between Salmonella Typhimurium and host cells in the gallbladder and showed that this pathogen can successfully invade gallbladder epithelial cells and proliferate. Additionally, we showed that Salmonella Typhimurium can use bile phospholipids to grow at high rates. These abilities are likely important for quick colonization of the gallbladder during typhoid fever and further pathogen dissemination through fecal shedding. To further characterize the interactions between Salmonella and the gallbladder environment, we compared the transcriptomes of Salmonella cultures grown in LB broth or physiological murine bile. Our data showed that many genes involved in bacterial central metabolism are affected by bile, with the citric acid cycle being repressed and alternative respiratory systems being activated. Additionally, our study revealed a new aspect of Salmonella interactions with bile through the identification of the global regulator phoP as a bile-responsive gene. Repression of phoP expression could also be achieved using physiological, but not commercial, bovine bile. The biological activity does not involve PhoPQ sensing of a bile component and is not caused by bile acids, the most abundant organic components of bile. Bioactivity-guided purification allowed the identification of a subset of small molecules from bile that can elicit full activity; however, a single compound with phoP inhibitory activity could not be isolated, suggesting that multiple molecules may act in synergy to achieve this effect. Due to the critical role of phoP in Salmonella virulence, further studies in this area will likely reveal aspects of the interaction between Salmonella

  1. Distribution and Antimicrobial Susceptibility of Foodborne Salmonella Serovars in Eight Provinces in China from 2007 to 2012 (Except 2009).

    Science.gov (United States)

    Wang, Yin; Cao, Chenyang; Alali, Walid Q; Cui, Shenghui; Li, Fengqin; Zhu, Jianghui; Wang, Xin; Meng, Jianghong; Yang, Baowei

    2017-07-01

    One thousand four hundred ninety-one Salmonella isolates recovered from retail foods including chicken, beef, fish, pork, dumplings, and cold dishes in China in 2007, 2008, 2010, 2011, and 2012 were analyzed for distribution of serotype and antimicrobial susceptibility. A total of 129 Salmonella serotypes were detected among 1491 isolates. Salmonella Enteritidis (21.5%), Typhimurium (11.0%), Indiana (10.8%), Thompson (5.4%), Derby (5.1%), Agona (3.8%), and Shubra (3.0%) were the seven most important serotypes in 1491 isolates. For antibiotic susceptibility, except 16 (1.1%) isolates were susceptible to all tested antibiotics, 131 (8.8%) resisted 1-2 and 1344 (90.1%) resisted three or more antibiotics. One thousand forty-six (70.2%) of 1491 Salmonella isolates were identified as multidrug-resistant (MDR) isolates, which could resist three or more categories of antibiotics. Resistance to sulfisoxazole (78.1%) was most common among the tested Salmonella, followed by tetracycline (70.6%), trimethoprim/sulfamethoxazole (68.0%), and nalidixic acid (63.4%). Resistances to amikacin (20.0%), levofloxacin (18.7%), gatifloxacin (17.9%), ceftriaxone (17.7%), and cefoxitin (13.2%) were less frequently detected. Resistance to fluoroquinolones was most common among Salmonella Shubra and Indiana isolates, while resistance to cephalosporins was frequently detected among Salmonella Thompson isolates. The results highlighted the diversity of Salmonella serotypes and the high prevalence of Salmonella MDR isolates in China. Compared with Salmonella Enteritidis and Typhimurium isolates, the higher fluoroquinolones and cephalosporins resistance rates of some individual serotypes (Salmonella Shubra, Indiana, and Thompson) also provided more information for further study related to fluoroquinolones or cephalosporin-resistant Salmonella.

  2. A novel Salmonella serovar isolated from Peregrine Falcon (Falco peregrinus nestlings in Sweden: Salmonella enterica enterica serovar Pajala (Salmonella Pajala

    Directory of Open Access Journals (Sweden)

    Jorge Hernández

    2012-08-01

    Full Text Available A novel Salmonella serovar was isolated from Peregrine falcon (Falco peregrinus nestlings in northern Sweden in 2006. Three isolates of the same clone was retrieved from three falcon siblings and characterized as Salmonella enterica sub-species enterica: O-phase 13, 23:-: e, n, z 15 and the H-phase was not present. We propose the geographical name Salmonella enterica, sub-species enterica serovar Pajala to this novel Salmonella.

  3. Inhibitory Effects of Several Essential Oils towards Salmonella typhimurium, Salmonella paratyphi A and Salmonella paratyphi B

    Directory of Open Access Journals (Sweden)

    S.F. Mazhar

    2014-09-01

    Full Text Available Plant essential oils are natural products extracted from plants and because of their antimicrobial properties can be used as natural additives in foods. They are also useful for decontamination of food-borne pathogens and can be a safe additive in foods. The antimicrobial activities of essential oils belonging to Saturiea hortensis, Thymus vulgaris, Mentha polegium, Cuminum cyminum, Lavandula officinalis and Mentha viridis L. (spearmint were investigated at different concentrations (0.1, 0.3, 0.5, 1, 2, 5 and 10%v/v against Salmonella typhimurium, Salmonella paratyphi A and Salmonella paratyphi B by using the agar well diffusion method. Essential oils showed inhibitory effect on Salmonella spp. in the agar well diffusion assay. In addition, the capability of essential oils for decontamination of minced row beef, ground beef, minced raw chicken and minced raw fish inoculated with Salmonella spp. at 0.1 and 0.5%v/v were assessed. Reduction of the Salmonella spp. population was observed following the inoculation of the cultures with 0.1 and 0.5%v/v essential oils.

  4. Salmonella Typhimurium transcription profiles in space flight

    Data.gov (United States)

    National Aeronautics and Space Administration — Salmonella transcription profiles were obtained from samples flown on space shuttle mission STS-115 and compared to profiles from Salmonella grown under identical...

  5. Laboratory monitoring of bacterial gastroenteric pathogens Salmonella and Shigella in Shanghai, China 2006-2012.

    Science.gov (United States)

    Zhang, J; Wang, F; Jin, H; Hu, J; Yuan, Z; Shi, W; Yang, X; Meng, J; Xu, X

    2015-02-01

    In 2006 we initiated an enhanced laboratory-based surveillance of Salmonella and Shigella infections in Shanghai, China. A total of 4483 Salmonella and 2226 Shigella isolates were recovered from stool specimens by 2012. In 80 identified Salmonella serovars, Enteritidis (34·5%) and Typhimurium (26·2%) were the most common. Shigella (S.) sonnei accounted for 63·9% of human Shigella infections over the same time period, and replaced S. flexneri to become the primary cause of shigellosis since 2010. Overall, a high level of antimicrobial resistance was observed in Salmonella and Shigella, particularly to nalidixic acid, ampicillin, and tetracycline. Ciprofloxacin resistance was common in Salmonella Typhimurium (21·0%) and S. flexneri (37·6%). The cephalosporin resistance in both pathogens also increased over the years, ranging from 3·4% to 7·0% in Salmonella, and from 10·4% to 28·6% in Shigella. Resistance to multiple antimicrobials was also identified in a large number of the isolates. This study provides insight into the distribution of Salmonella and Shigella in diarrhoeal diseases.

  6. Prevalence and antimicrobial susceptibility of Salmonella and Shigella spp. among children with gastroenteritis in an Iranian referral hospital.

    Science.gov (United States)

    Mahmoudi, Shima; Pourakbari, Babak; Moradzadeh, Mina; Eshaghi, Hamid; Ramezani, Amitis; Haghi Ashtiani, Mohammad Taghi; Keshavarz Valian, Sepideh; Mamishi, Setareh

    2017-08-01

    Gastroenteritis is one of the leading cause of illnesses through the world, especially in developing countries.Salmonella and Shigella infections are considered as the main public health problems in children. The aim of this study was to detect the prevalence and antimicrobial susceptibility of Salmonella and Shigella spp. among children with gastroenteritis in an Iranian referral hospital. During April 2013 to April 2014, all medical records of children with gastroenteritis admitted to a pediatric medical center were evaluated. Positive stool cultures of children were evaluated and frequency of Salmonella and Shigella spp. and their antimicrobial susceptibility were detected. In this study, 676 patients with the mean age of 24.94 months were enrolled. Eighty-eight (42%) Salmonella spp., 85 (40%) Shigella spp., 33 (16%) E. coli and 5(2%) candida albicans were isolated from 211 positive stool cultures. Among 85 Shigella spp. isolates, S. sonnei, S. flexneri and other Shigella spp. were isolated from 39 (46%) isolates, 36(42%) and 10(12%), respectively. Among 88 isolated Salmonella spp., 36 (41%) isolates were Salmonella Serogroup D, 26 (30%) were Salmonella Serogroup B, 20 (23%) isolates were Salmonella Serogroup C and 6 (7%) were other Salmonella spp. isolates. Thirty-eight percent of Salmonella serogroup B were resistant to nalidixic acid, while higher frequency of nalidixic acid resistant was found in Salmonella serogroup C and Salmonella serogroup D. The higher frequency of ampicillin resistant was found in Shigella spp. than Salmonella spp. High frequency of cefotaxime resistant was seen in S. sonei and S. flexneri (77% and 56%, respectively), whereas more than 90% of Salmonella serogroup B, C and D were susceptible to this antibiotic. In conclusion, Shigella and Salmonella serogroups can be considered as important etiological agents of acute diarrhea in children. Since the prevalence of antibiotic resistance is increasing in recent years in Iran, further

  7. Phenotypic and molecular characterization of Salmonella serotypes ...

    African Journals Online (AJOL)

    The presence of Salmonella and human pathogens in unpasteurized milk remains a public health hazard. The study reported the phenotypic and molecular characterization of Salmonella serotypes in cow raw milk, cheese and traditional yoghurt marketed for man's consumption in Nigeria. Isolation of Salmonella was done ...

  8. Vaccines against invasive Salmonella disease

    Science.gov (United States)

    MacLennan, Calman A; Martin, Laura B; Micoli, Francesca

    2014-01-01

    Though primarily enteric pathogens, Salmonellae are responsible for a considerable yet under-appreciated global burden of invasive disease. In South and South-East Asia, this manifests as enteric fever caused by serovars Typhi and Paratyphi A. In sub-Saharan Africa, a similar disease burden results from invasive nontyphoidal Salmonellae, principally serovars Typhimurium and Enteritidis. The existing Ty21a live-attenuated and Vi capsular polysaccharide vaccines target S. Typhi and are not effective in young children where the burden of invasive Salmonella disease is highest. After years of lack of investment in new Salmonella vaccines, recent times have seen increased interest in the area led by emerging-market manufacturers, global health vaccine institutes and academic partners. New glycoconjugate vaccines against S. Typhi are becoming available with similar vaccines against other invasive serovars in development. With other new vaccines under investigation, including live-attenuated, protein-based and GMMA vaccines, now is an exciting time for the Salmonella vaccine field. PMID:24804797

  9. Susceptibility of Salmonella Biofilm and Planktonic Bacteria to Common Disinfectant Agents Used in Poultry Processing.

    Science.gov (United States)

    Chylkova, Tereza; Cadena, Myrna; Ferreiro, Aura; Pitesky, Maurice

    2017-07-01

    Poultry contaminated with Salmonella enterica subsp. enterica are a major cause of zoonotic foodborne gastroenteritis. Salmonella Heidelberg is a common serotype of Salmonella that has been implicated as a foodborne pathogen associated with the consumption of improperly prepared chicken. To better understand the effectiveness of common antimicrobial disinfectants (i.e., peroxyacetic acid [PAA], acidified hypochlorite [aCH], and cetylpyridinium chloride [CPC]), environmental isolates of nontyphoidal Salmonella were exposed to these agents under temperature, concentration, and contact time conditions consistent with poultry processing. Under simulated processing conditions (i.e., chiller tank and dipping stations), the bacteriostatic and bactericidal effects of each disinfectant were assessed against biofilm and planktonic cultures of each organism in a disinfectant challenge. Log reductions, planktonic MICs, and mean biofilm eradication concentrations were computed. The biofilms of each Salmonella isolate were more resistant to the disinfectants than were their planktonic counterparts. Although PAA was bacteriostatic and bactericidal against the biofilm and planktonic Salmonella isolates tested at concentrations up to 64 times the concentrations commonly used in a chiller tank during poultry processing, aCH was ineffective against the same isolates under identical conditions. At the simulated 8-s dipping station, CPC was bacteriostatic against all seven and bactericidal against six of the seven Salmonella isolates in their biofilm forms at concentrations within the regulatory range. These results indicate that at the current contact times and concentrations, aCH and PAA are not effective against these Salmonella isolates in their biofilm state. The use of CPC should be considered as a tool for controlling Salmonella biofilms in poultry processing environments.

  10. Diversity and antimicrobial susceptibility of Salmonella enterica serovars isolated from pig farms in Ibadan, Nigeria

    DEFF Research Database (Denmark)

    Fashae, Kayode; Hendriksen, Rene S.

    2014-01-01

    of plasmid-mediated quinolone resistance (PMQR) genes in pigs in Ibadan, Nigeria. Pooled fresh pen floor fecal samples of pigs collected from 31 pig farms were cultured; the Salmonella isolates were serotyped and their antimicrobial susceptibility was determined. PMQR genes were screened by polymerase chain...... Kingston (n = 13; 5.7 %). The most widely distributed serovars among the farms were Salmonella Give (six farms) and Salmonella Elisaberthville (six farms). Resistance to chloramphenicol, sulfonamides, nalidixic acid, streptomycin, and tetracycline ranged from 11.6 % (n = 26) to 22.8 % (n = 51). Resistance....... Other PMQR genes were not detected. Pigs constitute an important source of diverse Salmonella serovars in Ibadan. The isolates were more resistant to old antimicrobials with some multiple resistant. Control measures and regulation of antimicrobials are warranted....

  11. Effects of transparent exopolymer particles and suspended particles on the survival of Salmonella enterica serovar Typhimurium in seawater.

    Science.gov (United States)

    Davidson, Marion C F; Berardi, Terra; Aguilar, Beatriz; Byrne, Barbara A; Shapiro, Karen

    2015-03-01

    The bacterium Salmonella enterica can infect marine mammals and has been increasingly implicated in seafood-borne disease outbreaks in humans. Despite the risk this zoonotic agent poses to animals and people, little is known regarding the environmental factors that affect its persistence in the sea. The goal of this study was to evaluate the impact of two constituents on the survival of Salmonella in the marine environment: transparent exopolymer particles (TEP) and suspended particles. A decay experiment was conducted by spiking Salmonella into bottles containing seawater, seawater with alginic acid as a source of TEP, filtered seawater or filtered seawater with alginic acid. Survival of Salmonella was monitored using culture followed by enrichment assays to evaluate if the bacteria entered a viable but non-cultivable (VBNC) state. Salmonella cell counts dropped significantly faster (P ≤ 0.05) in the unfiltered seawater samples with and without TEP. The slowest decay occurred in filtered seawater containing alginic acid, with VBNC Salmonella persisting for 17 months. These findings suggest that TEP may favor Salmonella survival while suspended particles facilitate its decay. Insight on the survival of allochthonous, zoonotic pathogens in seawater can guide monitoring, management and policy decisions relevant to wildlife and human public health. © FEMS 2015. All rights reserved. For Permissions, please e-mail: journals.permissions@oup.com.

  12. Differential outcome of infection with attenuated Salmonella in MyD88-deficient mice is dependent on the route of administration.

    Science.gov (United States)

    Issac, Jincy M; Sarawathiamma, Dhanya; Al-Ketbi, Mai I; Azimullah, Sheikh; Al-Ojali, Samia M; Mohamed, Yassir A; Flavell, Richard A; Fernandez-Cabezudo, Maria J; al-Ramadi, Basel K

    2013-01-01

    Activation of the innate immune system is a prerequisite for the induction of adaptive immunity to both infectious and non-infectious agents. TLRs are key components of the innate immune recognition system and detect pathogen-associated molecular patterns. Most TLRs utilize the MyD88 adaptor for their signaling pathways. In the current study, we investigated innate and adaptive immune responses to primary as well as secondary Salmonella infections in MyD88-deficient (MyD88(-/-)) mice. Using i.p. or oral route of inoculation, we demonstrate that MyD88(-/-) mice are hypersusceptible to infection by an attenuated, double auxotrophic, mutant of Salmonella enterica serovar Typhimurium (S. typhimurium). This is manifested by 2-3 logs higher bacterial loads in target organs, delayed recruitment of phagocytic cells, and defective production of proinflammatory cytokines in MyD88(-/-) mice. Despite these deficiencies, MyD88(-/-) mice developed Salmonella-specific memory Th1 responses and produced elevated serum levels of anti-Salmonella Abs, not only of Th1-driven (IgG2c, IgG3) but also IgG1 and IgG2b isotypes. Curiously, these adaptive responses were insufficient to afford full protection against a secondary challenge with a virulent strain of S. typhimurium. In comparison with the high degree of mortality seen in MyD88(-/-) mice following i.p. inoculation, oral infections led to the establishment of a state of long-term persistence, characterized by continuous bacterial shedding in animal feces that lasted for more than 6 months, but absence from systemic organs. These findings suggest that the absent expression of MyD88 affects primarily the innate effector arm of the immune system and highlights its critical role in anti-bacterial defense. Copyright © 2012 Elsevier GmbH. All rights reserved.

  13. Occurrence and antimicrobial resistance of Salmonella spp. isolated from food other than meat in Poland

    Directory of Open Access Journals (Sweden)

    Łukasz Mąka

    2015-09-01

    Full Text Available Introduction and objectives. Antimicrobial resistance of pathogenic bacteria can result in therapy failure, increased hospitalization, and increased risk of death. In Poland, [i]Salmonella[/i] spp. is a major bacterial agent of food poisoning. The majority of studies on antimicrobial resistance in [i]Salmonella[/i] spp. isolates from food have focused on meat products as the source of this pathogen. In comparison, this study examines the antimicrobial susceptibility of [i]Salmonella[/i] spp. isolated from retail food products other than meat in Poland. Materials and Methods. A collection of 122 [i]Salmonella[/i] spp. isolates were isolated in Poland in 2008–2012 from foods other than meat: confectionery products, eggs, fruits, vegetables, spices and others. The resistance of these isolates to 19 antimicrobial agents was tested using the disc diffusion method. Results. [i]Salmonella[/i] Enteritidis was the most frequently identified serotype (84.4% of all tested isolates. In total, 42.6% of the [i]Salmonella[/i] spp. isolates were resistant to antibiotics. The highest frequencies of resistance were observed in isolates from 2009 (60.0% and 2012 (59.5%. Antibiotic resistance was most prevalent among [i]Salmonella[/i] spp. isolated from egg-containing food samples (68.0%. Resistance to nalidixic acid was most common and was observed in 35.2% of all tested isolates. The isolates were less frequently resistant to sulphonamides (6.6%, ampicillin (4.9%, amoxicillin/clavulanic acid (2.5% and to streptomycin, cefoxitin, gentamicin and tetracycline (1.6%. Only one isolate showed resistance to chloramphenicol. Four isolates displayed multiresistance. Conclusions. Although, the level of resistance and multiresistance of [i]Salmonella[/i] spp. isolates from non-meat foods was lower than in those from meat products, the presence of these resistant bacteria poses a real threat to the health of consumers.

  14. Detection of Salmonella in Meat

    DEFF Research Database (Denmark)

    Löfström, Charlotta; Hansen, Flemming; Mansdal, Susanne

    2012-01-01

    Cost-effective and rapid monitoring of Salmonella in the meat production chain can contribute to food safety. The objective of this study was to validate an easy-to-use pre-PCR sample preparation method based on a simple boiling protocol for screening of Salmonella in meat and carcass swab samples...... obtained (SP, SE, and AC were 100, 95, and 97%, respectively). This test is under implementation by the Danish meat industry, and can be useful for screening of large number of samples in the meat production, especially for fast release of minced meat with a short shelf life....

  15. Occurrence of Salmonella spp. in broiler chicken carcasses and their susceptibility to antimicrobial agents Ocorrência de Salmonella spp. em carcaças de frango e sua suscetibilidade a agentes antimicrobianos

    Directory of Open Access Journals (Sweden)

    Dalila Angélica Moliterno Duarte

    2009-09-01

    Full Text Available The present study was carried out to evaluate the occurrence of Salmonellae in broiler chicken carcasses and to determine the antimicrobial resistance profile of the isolated strains. Twenty-five out of the 260 broiler chicken carcasses samples (9.6% were positive for Salmonella. S. Enteritidis was the most frequent serovar. Nineteen Salmonella isolates were tested for antimicrobial resistance, and the results indicated that 94.7% were resistant to at least one antimicrobial agent. Resistance to streptomycin (73.7%, nitrofurantoin (52.3%, tetracycline (31.6%, and nalidixic acid (21% were the prevalent amongst Salmonella strains tested.O presente estudo teve como objetivo verificar a ocorrência de Salmonellae em amostras de carcaças de frango e a suscetibilidade dos isolados a agentes antimicrobianos. Das 260 carcaças analisadas, 25 (9,6% foram positivas para Salmonella. Salmonella Enteritidis foi o sorovar predominante. Com relação à suscetibilidade a agentes antimicrobianos, 94,7% das cepas de Salmonella testadas, apresentaram resistência a um ou mais agentes antimicrobianos. Os perfís de resistência mais comumente observados entre os isolados foram a resistência à estreptomicina (73,7%, nitrofurantoína (52,3%, tetraciclina (31,6% e ácido nalidíxico (21%.

  16. Methionine sulphoxide reductases revisited: free methionine as a primary target of H2O2 stress in auxotrophic fission yeast

    OpenAIRE

    García Santamarina, Sarela, 1978-; Boronat i Llop, Susanna, 1965-; Ayté del Olmo, José; Hidalgo Hernando, Elena

    2013-01-01

    Amino acid methionine can suffer reversible oxidation to sulphoxide and further irreversible over-oxidation to methionine sulphone. As part of the cellular antioxidant scavenging activities are the methionine sulphoxide reductases (Msrs), with a reported role in methionine sulphoxide reduction, both free and in proteins. Three families of Msrs have been described, but the fission yeast genome only includes one representative for two of these families: MsrA/Mxr1 and MsrB/Mxr2. We have investig...

  17. Prevalence and susceptibility of salmonella Typhi and salmonella ...

    African Journals Online (AJOL)

    Methods: Blood samples collected from presumptive typhoid fever patients from Ahmadu Bello University (ABU), Federal College of Education (FCE) and presumptive typhoid fever patients that attended two private clinics (Salama Clinics and Savanna Polyclinics) in Zaria were cultured for Salmonella species and identified ...

  18. In vitro characterization and in vivo properties of Salmonellae lytic bacteriophages isolated from free-range layers

    Directory of Open Access Journals (Sweden)

    L Fiorentin

    2004-06-01

    Full Text Available Occurrence of food poisoning related to Salmonella-contaminated eggs and chicken meat has been frequent in humans. Salmonella Enteritidis (SE and Salmonella Typhimurium (ST are included among the most important paratyphoid salmonellae associated with chicken meat and eggs. Elimination of Salmonella at the pre-harvest stage can play a significant role in preventing the introduction of this pathogen into the food chain and consequently in the reduction of food poisoning in humans. Bactericidal bacteriophages may provide a natural, nontoxic, feasible and non-expensive component of the multi-factorial approach for a pre-harvest control of Salmonella in poultry. Five bacteriophages lytic for SE PT4 and ST were obtained from 107 samples of feces of free-range layers in Brazil. All bacteriophages were characterized in vitro and in vivo, showing head and tail morphology and dsDNA as nucleic acids. Results of "in vivo" studies suggested that bacteriophages do not remain in Salmonella-free birds longer than one day, whereas they multiply in Salmonella-infected birds for longer periods. Besides, selection for phage-resistant SE PT4 did not seem to occur in the short term. Isolated bacteriophages will be investigated for their potential for pre-harvest biocontrol of SE PT4 in poultry.

  19. Comparison of four sampling methods for the detection of Salmonella in broiler litter.

    Science.gov (United States)

    Buhr, R J; Richardson, L J; Cason, J A; Cox, N A; Fairchild, B D

    2007-01-01

    Experiments were conducted to compare litter sampling methods for the detection of Salmonella. In experiment 1, chicks were challenged orally with a suspension of naladixic acid-resistant Salmonella and wing banded, and additional nonchallenged chicks were placed into each of 2 challenge pens. Nonchallenged chicks were placed into each nonchallenge pen located adjacent to the challenge pens. At 7, 8, 10, and 11 wk of age the litter was sampled using 4 methods: fecal droppings, litter grab, drag swab, and sock. For the challenge pens, Salmonella-positive samples were detected in 3 of 16 fecal samples, 6 of 16 litter grab samples, 7 of 16 drag swabs samples, and 7 of 16 sock samples. Samples from the nonchallenge pens were Salmonella positive in 2 of 16 litter grab samples, 9 of 16 drag swab samples, and 9 of 16 sock samples. In experiment 2, chicks were challenged with Salmonella, and the litter in the challenge and adjacent nonchallenge pens were sampled at 4, 6, and 8 wk of age with broilers remaining in all pens. For the challenge pens, Salmonella was detected in 10 of 36 fecal samples, 20 of 36 litter grab samples, 14 of 36 drag swab samples, and 26 of 36 sock samples. Samples from the adjacent nonchallenge pens were positive for Salmonella in 6 of 36 fecal droppings samples, 4 of 36 litter grab samples, 7 of 36 drag swab samples, and 19 of 36 sock samples. Sock samples had the highest rates of Salmonella detection. In experiment 3, the litter from a Salmonella-challenged flock was sampled at 7, 8, and 9 wk by socks and drag swabs. In addition, comparisons with drag swabs that were stepped on during sampling were made. Both socks (24 of 36, 67%) and drag swabs that were stepped on (25 of 36, 69%) showed significantly more Salmonella-positive samples than the traditional drag swab method (16 of 36, 44%). Drag swabs that were stepped on had comparable Salmonella detection level to that for socks. Litter sampling methods that incorporate stepping on the sample

  20. Genotypic and phenotypic characterization of multidrug resistant Salmonella Typhimurium and Salmonella Kentucky strains recovered from chicken carcasses.

    Directory of Open Access Journals (Sweden)

    Rizwana Tasmin

    Full Text Available Salmonella Typhimurium is the leading cause of human non-typhoidal gastroenteritis in the US. S. Kentucky is one the most commonly recovered serovars from commercially processed poultry carcasses. This study compared the genotypic and phenotypic properties of two Salmonella enterica strains Typhimurium (ST221_31B and Kentucky (SK222_32B recovered from commercially processed chicken carcasses using whole genome sequencing, phenotype characterizations and an intracellular killing assay. Illumina MiSeq platform was used for sequencing of two Salmonella genomes. Phylogenetic analysis employing homologous alignment of a 1,185 non-duplicated protein-coding gene in the Salmonella core genome demonstrated fully resolved bifurcating patterns with varying levels of diversity that separated ST221_31B and SK222_32B genomes into distinct monophyletic serovar clades. Single nucleotide polymorphism (SNP analysis identified 2,432 (ST19 SNPs within 13 Typhimurium genomes including ST221_31B representing Sequence Type ST19 and 650 (ST152 SNPs were detected within 13 Kentucky genomes including SK222_32B representing Sequence Type ST152. In addition to serovar-specific conserved coding sequences, the genomes of ST221_31B and SK222_32B harbor several genomic regions with significant genetic differences. These included phage and phage-like elements, carbon utilization or transport operons, fimbriae operons, putative membrane associated protein-encoding genes, antibiotic resistance genes, siderophore operons, and numerous hypothetical protein-encoding genes. Phenotype microarray results demonstrated that ST221_31B is capable of utilizing certain carbon compounds more efficiently as compared to SK222_3B; namely, 1,2-propanediol, M-inositol, L-threonine, α-D-lactose, D-tagatose, adonitol, formic acid, acetoacetic acid, and L-tartaric acid. ST221_31B survived for 48 h in macrophages, while SK222_32B was mostly eliminated. Further, a 3-fold growth of ST221_31B was

  1. The growth rate of pyrimidine auxotrophic mutants of Lactococcus lactis MG1363 is reduced in the presence of exogenous aspartate

    DEFF Research Database (Denmark)

    Hansen, Steen Lyders Lerche; Martinussen, Jan

    1998-01-01

    Nucleotide metabolism is important for all cells as supplier of building blocks for the synthesis of nucleic acids and coenzymes. Furthermore, they act as intracellular energy carriers and allosteric effectors in a large number of enzymatic reactions. Nucleotides can either be made de novo or from...... encoding enzymes in the distal part of the pyrimidine biosynthetic pathway of L. lactis MG1363, results in reduction of the growth rate if exogenous aspartate is supplied to the growth medium. This observation can be explained by an increased accumulation of a toxic intermediate, most likely carbamoyl...... aspartate, provoked by high concentrations of aspartate....

  2. Cellulitis Due to Salmonella infantis.

    Directory of Open Access Journals (Sweden)

    Satish R Patil

    2013-01-01

    Full Text Available Bacteria of the genus Salmonella are highly adapted for the growth in both humans and animals and cause a wide spectrum of disease. The growth of Serotypes S. typhi and S. paratyphi is restricted to human hosts, in whom these organisms cause enteric (typhoid fever. The remaining Serotypes (non typhoidal Salmonella or NTS can colonize the gastrointestinal tracts of the broad range of animals, including mammals, reptiles, birds and insects. The usual clinical presentation of non-typhoidal salmonellae (NTS infection is self limited gastroenteritis; however bacteremia and focal extra intestinal infection may occur. However salmonella localization to the skin presenting as cutaneous ulceration is regarded as a rare event. Rates of morbidity and mortality associated with NTS are highest among the elderly, infants, and immunocompromised individuals, including those with hemoglobinopathies, HIV infection, or infections that cause blockade of the reticuloendothelial system. We isolated S.infantis in 50 years old man with left leg cellulitis. The serotype was confirmed at Central Research Institute, Kasauli.

  3. Salmonella radicidation of poultry carcasses

    NARCIS (Netherlands)

    Mulder, R.W.A.W.

    1982-01-01

    Validity of methods

    Experiments were carried out In which it was assessed which Salmonella isolation method is the most productive one In the examination of broiler carcasses. Refrigerated, refrigerated and radiated (2.50 kGy), frozen and frozen and

  4. Salmonella-secreted Virulence Factors

    Energy Technology Data Exchange (ETDEWEB)

    Heffron, Fred; Niemann, George; Yoon, Hyunjin; Kidwai, Afshan S.; Brown, Roslyn N.; McDermott, Jason E.; Smith, Richard D.; Adkins, Joshua N.

    2011-05-01

    In this short review we discuss secreted virulence factors of Salmonella, which directly affect Salmonella interaction with its host. Salmonella secretes protein to subvert host defenses but also, as discussed, to reduce virulence thereby permitting the bacteria to persist longer and more successfully disperse. The type III secretion system (TTSS) is the best known and well studied of the mechanisms that enable secretion from the bacterial cytoplasm to the host cell cytoplasm. Other secretion systems include outer membrane vesicles, which are present in all Gram-negative bacteria examined to date, two-partner secretion, and type VI secretion will also be addressed. Excellent reviews of Salmonella secreted effectors have focused on themes such as actin rearrangements, vesicular trafficking, ubiquitination, and the activities of the virulence factors themselves. This short review is based on S. Typhimurium infection of mice because it is a model of typhoid like disease in humans. We have organized effectors in terms of events that happen during the infection cycle and how secreted effectors may be involved.

  5. Salmonella Infection and Water Frogs

    Centers for Disease Control (CDC) Podcasts

    2010-01-12

    This podcast, featuring lead investigator Shauna Mettee, discusses the first known outbreak of Salmonella in people due to contact with water frogs.  Created: 1/12/2010 by National Center for Zoonotic, Vector-Borne, and Enteric Diseases (NCZVED).   Date Released: 1/12/2010.

  6. Occurrence of purulent arthritis broilers vertically infected with Salmonella enterica serovar Enteritidis in Korea.

    Science.gov (United States)

    Oh, J-Y; Kang, M-S; An, B-K; Song, E-A; Kwon, J-H; Kwon, Y-K

    2010-10-01

    Salmonella enterica serovar Enteritidis (Salmonella Enteritidis) has been associated with morbidity and mortality in broiler chickens worldwide. The present study described purulent arthritis of broilers infected with Salmonella Enteritidis and investigated antibiograms and genetic characteristics of Salmonella Enteritidis isolates from epidemiologically related properties such as a hatchery and breeder farm in an attempt to elucidate the source of contamination. Clinical disease and mortality were observed in the affected broiler flock. Mortality was 5.8% until 12 d of age. The birds typically showed lameness with moderately swollen hock joints and footpads. The most prevalent lesions were severely purulent arthritis with polyserositis. Histopathology revealed moderate to severe inflammation in the synovial membrane of leg joints and visceral organs. When the antimicrobial susceptibility test was performed against 7 isolates of Salmonella Enteritidis from broilers, and relevant hatchery and breeder farms by the disk diffusion method using 18 antimicrobial agents, isolates from broiler and breeder farms had the same antibiogram characterized by multiple drug resistance to ampicillin, ceftiofur, cephalothin, gentamycin, nalidixic acid, streptomycin, sulfisoxazole, and tetracycline, whereas isolates from the hatchery were differently resistant to only nalidixic acid. Through the genetic analysis with pulsed-field gel electrophoresis using the restriction enzyme XbaI, Salmonella Enteritidis isolates from both broiler and breeder farms also showed the same PFGE pattern compared with the hatchery isolates resistant to nalidixic acid. As a result, the same PFGE profiles and antibiogram patterns among isolates from broilers and breeder farms provided direct evidence of vertical Salmonella Enteritidis transmission from the contaminated breeder farm to commercial broiler.

  7. Occurrence of multidrug-resistant Salmonella enterica serovar Enteritidis isolates from poultry in Iran

    Directory of Open Access Journals (Sweden)

    Ghaderi, R.

    2016-03-01

    Full Text Available Salmonella enterica is recognized as one of the major food-borne pathogens with more than 2,500 serotypes worldwide. The present study addresses antimicrobial resistance of Salmonella enterica serovar Enteritidis isolates in Iran. A collection of 151 Salmonella spp. isolates collected from poultry were serotyped to identify Salmonella Enteritidis. Sixty-one Salmonella Enteritidis were subsequently tested against 30 antimicrobials. A high frequency of antimicrobial resistance was observed against nitrofurantoin (n=55, 90.2% followed by nalidixic acid (n=41, 67.2%, and cephalexin (n=23, 37.7%. Multi-drug resistance were observed in 35 (57.4% out of 61 isolates. Twenty-six antimicrobial resistance patterns were observed among the 61 Salmonella Enteritidis. All isolates were susceptible to ofloxacin, imipenem, enrofloxacin, chloramphenicol, gentamicin, and 3rd and 4th generation cephalosporins. In conclusion, our results revealed that implementing new policies toward overuse of antimicrobial drugs in Iranian poultry industry are of great importance.

  8. Commercially laid eggs vs. discarded hatching eggs: contamination by Salmonella spp.

    Science.gov (United States)

    Kottwitz, Luciana B M; Leão, Joice Aparecida; Back, Alberto; Rodrigues, Dalia dos P; Magnani, Marciane; de Oliveira, Tereza C R M

    2013-01-01

    Salmonella enterica is frequently associated with outbreaks of human salmonellosis, and products of avian origin, such as eggs and chicken meat, are the main vehicles of its transmission. The present study describes the occurrence of different serovars of Salmonella enterica and phagotypes of S. enterica serovar Enteritidis in eggs destined for human consumption. Four thousand eggs obtained from commercial egg laying farms and one thousand discarded hatching eggs from broiler farms, which were acquired at farmers' markets and informal shops, were analyzed. Salmonella spp. was isolated from 52.0% of the discarded hatching eggs, in which the predominant serovar was Enteritidis (84.6%), and the predominant Salmonella Enteritidis phagotype (PT) was PT7 (26.9%). Salmonella spp. was not isolated from eggs obtained from commercial egg laying farms. The antimicrobial resistance profile showed that 23.1% (n = 6) of the SE strains were resistant to nalidixic acid. The results suggest that the consumption of discarded hatching eggs represents an important source of Salmonella transmission to humans.

  9. 76 FR 81513 - Guidance for Industry: Prevention of Salmonella

    Science.gov (United States)

    2011-12-28

    ...] Guidance for Industry: Prevention of Salmonella Enteritidis in Shell Eggs During Production, Storage, and... ``Prevention of Salmonella Enteritidis in Shell Eggs During Production, Storage, and Transportation.'' The... final rule ``Prevention of Salmonella Enteritidis in Shell Eggs During Production, Storage, and...

  10. 75 FR 48973 - Draft Guidance for Industry: Prevention of Salmonella

    Science.gov (United States)

    2010-08-12

    ...] Draft Guidance for Industry: Prevention of Salmonella Enteritidis in Shell Eggs During Production... entitled ``Prevention of Salmonella Enteritidis in Shell Eggs During Production, Storage, and... on how to comply with certain provisions contained in FDA's final rule ``Prevention of Salmonella...

  11. Salmonella risk to consumers via pork is related to the Salmonella prevalence in pig feed.

    Science.gov (United States)

    Rönnqvist, M; Välttilä, V; Ranta, J; Tuominen, P

    2018-05-01

    Pigs are an important source of human infections with Salmonella, one of the most common causes of sporadic gastrointestinal infections and foodborne outbreaks in the European region. Feed has been estimated to be a significant source of Salmonella in piggeries in countries of a low Salmonella prevalence. To estimate Salmonella risk to consumers via the pork production chain, including feed production, a quantitative risk assessment model was constructed. The Salmonella prevalence in feeds and in animals was estimated to be generally low in Finland, but the relative importance of feed as a source of Salmonella in pigs was estimated as potentially high. Discontinuation of the present strict Salmonella control could increase the risk of Salmonella in slaughter pigs and consequent infections in consumers. The increased use of low risk and controlled feed ingredients could result in a consistently lower residual contamination in pigs and help the tracing and control of the sources of infections. Copyright © 2017 Elsevier Ltd. All rights reserved.

  12. Identification and characterization of salmonella serotypes using DNA spectral characteristics by fourier transform infrared (FT-IR) spectroscopy

    Science.gov (United States)

    Analysis of DNA samples of Salmonella serotypes (Salmonella Typhimurium, Salmonella Enteritidis, Salmonella Infantis, Salmonella Heidelberg and Salmonella Kentucky) were performed using Fourier transform infrared spectroscopy (FT-IR) spectrometer by placing directly in contact with a diamond attenua...

  13. Salmonella transfer during pilot plant scale washing and roller conveying of tomatoes.

    Science.gov (United States)

    Wang, Haiqiang; Ryser, Elliot T

    2014-03-01

    Salmonella transfer during washing and roller conveying of inoculated tomatoes was quantified using a pilot scale tomato packing line equipped with plastic, foam, or brush rollers. Red round tomatoes (2.3 kg) were dip inoculated with Salmonella enterica serovar Typhimurium LT2 (avirulent) (4 log CFU/g), air dried for 2 h, and then washed in sanitizer-free water for 2 min. Inoculated tomatoes were then passed single file over a 1.5-m conveyor equipped with plastic, foam, or brush rollers followed by 25 previously washed uninoculated tomatoes. Tomato samples were collected after 2 min of both washing and roller conveying, with all 25 uninoculated tomatoes collected individually after conveying. Roller surface samples were collected before and after conveying the uninoculated tomatoes. Both tomato and surface samples were quantitatively examined for Salmonella by direct plating or membrane filtration using xylose lysine Tergitol 4 agar. Regardless of the roller type, Salmonella populations on inoculated tomatoes did not significantly (P conveyors. After conveying uninoculated tomatoes over contaminated foam rollers, 96% of the 25 tomatoes were cross-contaminated with Salmonella at >100 CFU per tomato. With plastic rollers, 24 and 76% of tomatoes were cross-contaminated with Salmonella at 10 to 100 and 1 to 10 CFU per tomato, respectively. In contrast, only 8% of 25 tomatoes were cross-contaminated with brush rollers with Salmonella populations of 1 to 10 CFU per tomato. Overall, cross-contamination was greatest with foam, followed by plastic and brush rollers (P < 0.05). Adding peroxyacetic acid or chlorine to the wash water significantly decreased cross-contamination during tomato conveying, with chlorine less effective in controlling Salmonella on foam compared with plastic and brush rollers.

  14. Reduction of Salmonella on chicken meat and chicken skin by combined or sequential application of lytic bacteriophage with chemical antimicrobials.

    Science.gov (United States)

    Sukumaran, Anuraj T; Nannapaneni, Rama; Kiess, Aaron; Sharma, Chander Shekhar

    2015-08-17

    The effectiveness of recently approved Salmonella lytic bacteriophage preparation (SalmoFresh™) in reducing Salmonella in vitro and on chicken breast fillets was examined in combination with lauric arginate (LAE) or cetylpyridinium chloride (CPC). In another experiment, a sequential spray application of this bacteriophage (phage) solution on Salmonella inoculated chicken skin after a 20s dip in chemical antimicrobials (LAE, CPC, peracetic acid, or chlorine) was also examined in reducing Salmonella counts on chicken skin. The application of phage in combination with CPC or LAE reduced S. Typhimurium, S. Heidelberg, and S. Enteritidis up to 5 log units in vitro at 4 °C. On chicken breast fillets, phage in combination with CPC or LAE resulted in significant (p<0.05) reductions of Salmonella ranging from 0.5 to 1.3 log CFU/g as compared to control up to 7 days of refrigerated storage. When phage was applied sequentially with chemical antimicrobials, all the treatments resulted in significant reductions of Salmonella. The application of chlorine (30 ppm) and PAA (400 ppm) followed by phage spray (10(9)PFU/ml) resulted in highest Salmonella reductions of 1.6-1.7 and 2.2-2.5l og CFU/cm(2), respectively. In conclusion, the surface applications of phage in combination with LAE or CPC significantly reduced Salmonella counts on chicken breast fillets. However, higher reductions in Salmonella counts were achieved on chicken skin by the sequential application of chemical antimicrobials followed by phage spray. The sequential application of chlorine, PAA, and phage can provide additional hurdles to reduce Salmonella on fresh poultry carcasses or cut up parts. Copyright © 2015 Elsevier B.V. All rights reserved.

  15. Multidrug-Resistant Salmonella enterica Serovar Muenchen from Pigs and Humans and Potential Interserovar Transfer of Antimicrobial Resistance

    OpenAIRE

    Gebreyes, Wondwossen A.; Thakur, Siddhartha

    2005-01-01

    Salmonella serovars are important reservoirs of antimicrobial resistance. Recently, we reported on multidrug-resistant (MDR) Salmonella enterica serovar Typhimurium strains among pigs with resistance to ampicillin, kanamycin, streptomycin, sulfamethoxazole, and tetracycline (resistance [R] type AKSSuT) and resistance to amoxicillin-clavulanic acid, ampicillin, chloramphenicol, streptomycin, sulfamethoxazole, and tetracycline (R type AxACSSuT). In the present study, 67 isolates (39 from humans...

  16. Use of Attenuated but Metabolically Competent Salmonella as a Probiotic To Prevent or Treat Salmonella Infection

    Science.gov (United States)

    Sabag-Daigle, Anice; Blunk, Henry M.; Gonzalez, Juan F.; Steidley, Brandi L.; Boyaka, Prosper N.

    2016-01-01

    Salmonella enterica is among the most burdensome of foodborne disease agents. There are over 2,600 serovars that cause a range of disease manifestations ranging from enterocolitis to typhoid fever. While there are two vaccines in use in humans to protect against typhoid fever, there are none that prevent enterocolitis. If vaccines preventing enterocolitis were to be developed, they would likely protect against only one or a few serovars. In this report, we tested the hypothesis that probiotic organisms could compete for the preferred nutrient sources of Salmonella and thus prevent or treat infection. To this end, we added the fra locus, which encodes a utilization pathway for the Salmonella-specific nutrient source fructose-asparagine (F-Asn), to the probiotic bacterium Escherichia coli Nissle 1917 (Nissle) to increase its ability to compete with Salmonella in mouse models. We also tested a metabolically competent, but avirulent, Salmonella enterica serovar Typhimurium mutant for its ability to compete with wild-type Salmonella. The modified Nissle strain became more virulent and less able to protect against Salmonella in some instances. On the other hand, the modified Salmonella strain was safe and effective in preventing infection with wild-type Salmonella. While we tested for efficacy only against Salmonella Typhimurium, the modified Salmonella strain may be able to compete metabolically with most, if not all, Salmonella serovars, representing a novel approach to control of this pathogen. PMID:27185789

  17. Isolation and Evaluation Virulence Factors of Salmonella typhimurium and Salmonella enteritidis in Milk and Dairy Products

    Directory of Open Access Journals (Sweden)

    Shima Shaigan nia

    2014-06-01

    Conclusions: To our best knowledge the present study is the first prevalence report of Salmonella spp., Salmonella enteritidis and Salmonella typhimurium in raw sheep and goat samples in Iran. Consumption of pasteurized milk and dairy products can reduce the risk of salmonellosis.

  18. Evaluation of the protective efficacy of Salmonella Gallinarum 9R ...

    African Journals Online (AJOL)

    Evaluation of the protective efficacy of Salmonella Gallinarum 9R strain vaccine against Salmonella strains isolated from cases suspected of salmonellosis outbreaks in poultry farms in central Ethiopia.

  19. Salmonella Typhimurium infection in the porcine intestine

    DEFF Research Database (Denmark)

    Schauser, Kirsten; Olsen, John Elmerdahl; Larsson, Lars-Inge

    2005-01-01

    The normal intestinal epithelium is renewed with a turnover rate of 3-5 days. During Salmonella infection increased cell loss is observed, possibly as a result of programmed cell death (PCD). We have, therefore, studied the effects of Salmonella Typhimurium infection on three elements involved...... in scattered epithelial cells and the number of positive cells increased with increasing times of exposure to Salmonella (P

  20. Changing trends in antimicrobial resistance of Salmonella enterica serovar typhi and salmonella enterica serovar paratyphi A in Chennai

    Directory of Open Access Journals (Sweden)

    Krishnan Padma

    2009-10-01

    Full Text Available Background and Objectives: Chloramphenicol was considered the anti-microbial gold standard for typhoid treatment but, following the increasing worldwide frequency of antibiotic resistance, ciprofloxacin has been the mainstay of therapy since 1980. Recent studies have shown a shifting of susceptibility to conventional drugs like chloramphenicol, ampicillin and cotrimoxazole. The primary objective of the study was to evaluate the in vitro activity of chloramphenicol and other first-line drugs in comparison with cephalosporins and quinolones. Materials and Methods: Fifty isolates of Salmonella obtained from blood culture were subjected to serotyping at the Central Research Institute, Kasauli. Phage typing and biotyping was performed at the National Phage Typing Centre, New Delhi. Antibiotic sensitivity testing was carried out for 10 drugs by the Kirby-Bauer disc diffusion method and minimum inhibitory concentration by broth microdilution for nalidixic acid, chloramphenicol, ciprofloxacin, ceftriaxone, cefixime and ofloxacin. Multi-drug-resistant (MDR strains were checked for plasmid. Results: In the present study, 70 and 30% of the isolates were Salmonella enterica serovar typhi and paratyphi A, respectively. They were highly sensitive to chloramphenicol (86%, ampicillin (84% and cotrimoxazole (88%. Highest sensitivity was seen for cephalosporins, followed by quinolones. Seventeen/21 (81% and 100% of the Salmonella enterica serovar typhi strains belonged to E1 phage type and biotype 1, respectively. Antibiogram showed 2% of the strains to be sensitive to all the drugs tested and 12% were MDR and showed the presence of plasmids. Conclusion: The study indicates reemergence of chloramphenicol-susceptible Salmonella enterica serovar typhi and paratyphi A isolates, a significant decline in MDR strains and high resistance to nalidixic acid. E1 phage type and biotype 1 are found to be most prevalent in Chennai, India.

  1. Antimicrobial resistance, class 1 integrons, and genomic island 1 in Salmonella isolates from Vietnam.

    Directory of Open Access Journals (Sweden)

    An T T Vo

    Full Text Available BACKGROUND: The objective was to investigate the phenotypic and genotypic resistance and the horizontal transfer of resistance determinants from Salmonella isolates from humans and animals in Vietnam. METHODOLOGY/PRINCIPAL FINDINGS: The susceptibility of 297 epidemiologically unrelated non-typhoid Salmonella isolates was investigated by disk diffusion assay. The isolates were screened for the presence of class 1 integrons and Salmonella genomic island 1 by PCR. The potential for the transfer of resistance determinants was investigated by conjugation experiments. Resistance to gentamicin, kanamycin, chloramphenicol, streptomycin, trimethoprim, ampicillin, nalidixic acid, sulphonamides, and tetracycline was found in 13 to 50% of the isolates. Nine distinct integron types were detected in 28% of the isolates belonging to 11 Salmonella serovars including S. Tallahassee. Gene cassettes identified were aadA1, aadA2, aadA5, bla(PSE-1, bla(OXA-30, dfrA1, dfrA12, dfrA17, and sat, as well as open reading frames with unknown functions. Most integrons were located on conjugative plasmids, which can transfer their antimicrobial resistance determinants to Escherichia coli or Salmonella Enteritidis, or with Salmonella Genomic Island 1 or its variants. The resistance gene cluster in serovar Emek identified by PCR mapping and nucleotide sequencing contained SGI1-J3 which is integrated in SGI1 at another position than the majority of SGI1. This is the second report on the insertion of SGI1 at this position. High-level resistance to fluoroquinolones was found in 3 multiresistant S. Typhimurium isolates and was associated with mutations in the gyrA gene leading to the amino acid changes Ser83Phe and Asp87Asn. CONCLUSIONS: Resistance was common among Vietnamese Salmonella isolates from different sources. Legislation to enforce a more prudent use of antibiotics in both human and veterinary medicine should be implemented by the authorities in Vietnam.

  2. Similarities between Salmonella Enteritidis isolated from humans and captive wild animals in South Africa.

    Science.gov (United States)

    Smith, Anthony M; Ismail, Husna; Henton, Maryke M; Keddy, Karen H

    2014-12-15

    Salmonella is well recognized as an aetiological agent of gastrointestinal and diarrhoeal disease. Salmonella enterica serotype Enteritidis (Salmonella Enteritidis) is one of the commonest serotypes associated with foodborne illness. In South Africa, we compared Salmonella Enteritidis strains isolated from humans with gastroenteritis and strains isolated from captive wild animals, between June 2011 and July 2012. Bacteria were phenotypically characterized using standard microbiological techniques. Genotypic relatedness of isolates was investigated by pulsed-field gel electrophoresis (PFGE) analysis. a diversity of 27 PFGE patterns amongst 196 human non-invasive isolates was shown; two PFGE patterns predominated and accounted for 74% of all human isolates. Human isolates showed a 12% prevalence rate for nalidixic acid resistance. Animal isolates from 5 different sources were investigated. With the exception of an isolate from a ground hornbill, all animal isolates (jaguar, crocodile, lion and poultry) showed PFGE pattern matches to a human isolate. Animal isolates showed susceptibility to all antimicrobial agents tested, with the exception of nalidixic acid resistance in isolates from the lion and poultry source. Our data showed similarities between Salmonella Enteritidis strains isolated from humans and captive wild animals, suggesting a probable common source for strains from humans and animals.

  3. Molecular typing, antibiotic resistance, virulence gene and biofilm formation of different Salmonella enterica serotypes.

    Science.gov (United States)

    Turki, Yousra; Mehr, Ines; Ouzari, Hadda; Khessairi, Amel; Hassen, Abdennaceur

    2014-01-01

    Salmonella enterica isolates representing commonly isolated serotypes in Tunisia were analyzed using genotyping and phenotyping methods. ERIC and ITS-PCR applied to 48 Salmonella spp. isolates revealed the presence of 12 and 10 different profiles, respectively. The distribution of profiles among serotypes demonstrated the presence of strains showing an identical fingerprinting pattern. All Salmonella strains used in this study were positive for the sdiA gene. Three Salmonella isolates belonging to serotypes Anatum, Enteritidis and Amsterdam were negative for the invA gene. The spvC gene was detected in thirteen isolates belonging to serotypes Anatum, Typhimurium, Enteritidis, Gallinarum and Montevideo. Antibiotic resistance was frequent among the recovered Salmonella isolates belonging to serotypes Anatum, Typhimurium, Enteritidis, Zanzibar and Derby. The majority of these isolates exhibited resistance to at least two antibiotic families. Four multidrug-resistant isolates were recovered from food animals and poultry products. These isolates exhibited not only resistance to tetracycline, sulphonamides, and ampicillin, but also have shown resistance to fluoroquinolones. Common resistance to nalidixic acid, ciprofloxacin and ofloxacin in two S. Anatum and S. Zanzibar strains isolated from raw meat and poultry was also obtained. Furthermore, wastewater and human isolates exhibited frequent resistance to nalidixic acid and tetracycline. Of all isolates, 33.5% were able to form biofilm.

  4. Efficacy of sanitizers in reducing Salmonella on pecan nutmeats during cracking and shelling.

    Science.gov (United States)

    Beuchat, Larry R; Mann, David A; Alali, Walid Q

    2013-05-01

    Studies were done to evaluate the efficacy of chlorine (200 to 1,000 μg/ml), lactic acid (0.5 to 2%), levulinic acid (0.5 to 2%), sodium dodecyl sulfate (SDS, 0.05%), lactic acid plus SDS, levulinic acid plus SDS, and a mixed peroxyacid sanitizer (Tsunami 200, 40 and 80 μg/ml) in killing Salmonella on or in immersion- and on surface-inoculated pecan nutmeats (U.S. Department of Agriculture medium pieces and mammoth halves). The addition of SDS to treatment solutions containing lactic acid or levulinic acid resulted in generally higher reductions of Salmonella, but differences in these reductions were not always significant. Lactic and levulinic acids (2%) containing SDS (0.05%) were equivalent in killing Salmonella on immersion-inoculated nutmeats. Tsunami 200 (40 μg/ml) was less lethal or equivalent to 1 or 2% lactic and levulinic acids, with or without 0.05% SDS. Reductions did not exceed 1.1 log CFU/g of immersion-inoculated pieces and halves, regardless of sanitizer concentration or treatment time (up to 20 min). Reductions on surface-inoculated pieces and halves were 0.7 to 2.6 log CFU/g and 1.2 to 3.0 log CFU/g, respectively. Treatment with 2% lactic acid plus SDS (0.05%) and Tsunami (80 μg/ml) was most effective in killing Salmonella on surface-inoculated pieces; treatment of halves with chlorine (1,000 μg/ml) or lactic acid (1 or 2%), with or without SDS, was most efficacious. Exposure of immersion-inoculated pecan pieces to chlorine (200 μg/ml), lactic acid (2%) and levulinic acid (2%) with or without SDS, and Tsunami (80 μg/ml) during intermittent vacuum (18 ± 2 mbar) and ambient atmospheric pressure treatments for up to 20 min reduced Salmonella by only 0.1 to 1.0 log CFU/g. These studies emphasize the importance of preventing contamination of pecan nutmeats with Salmonella. Once nuts are contaminated, the lethality of sanitizers tested in this study is minimal.

  5. Serovars of Salmonella isolated from Danish turkeys between 1995 and 2000 and their antimicrobial resistance

    DEFF Research Database (Denmark)

    Pedersen, Karl; Hansen, H.C.; Jørgensen, J.C.

    2002-01-01

    , florfenicol, or amoxycillin with clavulanic acid, only 24 isolates were resistant to two or more compounds in various combinations of up to six compounds; one Salmonella Havana isolate was resistant to six compounds. Six isolates were serovar Typhimurium, but none of them belonged to phage type DT104....

  6. Administration of acidified drinking water to finishing pigs in order to prevent Salmonella infections

    NARCIS (Netherlands)

    Wolf, van der P.J.; Schie, van F.W.; Elbers, A.R.W.; Engel, B.; Heijden, van der H.; Hunneman, W.A.; Tielen, M.J.M.

    2001-01-01

    The aim of the study was to test whether acidified drinking water, with two millilitres of an acid mixture per litre, was able to reduce the number of Salmonella infections in finishing pig herds. In each compartment, half of the pens were supplied with acidified water and the other pens served as

  7. The addition of charcoals to broiler diets did not alter the recovery of Salmonella Typhimurium during grow-out.

    Science.gov (United States)

    Wilson, K M; Bourassa, D V; Davis, A J; Freeman, M E; Buhr, R J

    2016-03-01

    Two experiments evaluated prebiotics added to feed on the recovery of Salmonella in broilers during grow-out and processing. In Experiment 1, "seeder" chicks were inoculated with Salmonella Typhimurium and placed with penmates. Treatments were: basal control diet, added 0.3% bamboo charcoal, 0.6% bamboo charcoal, or 0.12% Aromabiotic (medium chain fatty acids). The ceca from seeders and penmates were sampled to confirm Salmonella colonization at 3, 4, and 6 wk, and pen litter was sampled weekly. At 3 wk, charcoal fed chicks had significantly lower cecal recovery (37% lower) of Salmonella via direct plating but no differences at wk 4 or 6. At 6 wk, broilers fed Aromabiotic had no recovery of Salmonella from ceca with direct plating and significantly, 18%, lower recovery with enrichment. In Experiment 2, the treatments were: basal control diet, added 0.3% bamboo charcoal, 0.3% activated bamboo charcoal, or 0.3% pine charcoal. At placement, 2 seeders were challenged with Salmonella and commingled with penmates and ceca sampled at 1 and 2 wk, and ceca from 5 penmates/pen at 3 to 6 wk. Weekly, the pH of the crop and duodenum was measured from 1 penmate/pen and the litter surface sampled. At the end of grow-out broilers were processed. Results showed that penmates had colonized at 1 and 2 wk. Cecal Salmonella showed no differences except at 4 wk, when activated bamboo charcoal had a 18% lower recovery of Salmonella (enrichment) compared to the control (88%). Similar to Experiment 1, the recovery of Salmonella from the litter was not significantly different among treatments, however an overall decrease in recovery by 4 wk with direct plating reoccurred. The pH of the duodenum and the crop were not different among treatments. Crop pH (6.0) for all treatments were significantly higher at wk 1 compared to wk 2 to 6. Charcoals had minimal effect on Salmonella recovery in the ceca, but following defeathering, broilers fed charcoals had significantly lower Salmonella

  8. Anaerobiosis induced virulence of Salmonella typhi

    DEFF Research Database (Denmark)

    Kapoor, Sarika; Singh, R D; Sharma, P C

    2002-01-01

    , we examined the effect of anaerobiosis on the virulence of Salmonella Typhi, a Gram negative bacteria which invades through the gut mucosa and is responsible for typhoid fever. METHODS: Salmonella Typhi (ty2) was cultured in aerobic and anaerobic conditions to compare its virulence by rabbit ileal...

  9. Antibiotic susceptibilities of Salmonella species prevalent among ...

    African Journals Online (AJOL)

    This study was conducted to assess the prevalence of Salmonella species among children having diarrhea in Katsina State, Nigeria. A total of 220 diarrhea stool samples of children aged five years and below (0-5 years) were collected and screened for Salmonella species using culture technique. Presumptively positive ...

  10. antimicrobial susceptibility pattern of Salmonella species

    African Journals Online (AJOL)

    user

    ABSTRACT. Treatment of enteric fever is increasingly becoming very challenging due to the increasing wave of antibiotic resistance. This study is a review of the contemporary antimicrobial susceptibility pattern of. Salmonella species. The antimicrobial susceptibility pattern of Salmonella species to a wide range of.

  11. Case Report: Salmonella lung infection | Ohanu | International ...

    African Journals Online (AJOL)

    A case of an 84 year old man admitted because of fever, abdominal discomfort, weakness, past history of cough wheezing and abuse of prednisolone and Erythromycin. He had Bronchopneumonia and diabetes. Salmonella typhimurium was isolated from both his sputum and blood while stool was negative for salmonella.

  12. Rapid detection and characterization of Salmonella enterica ...

    African Journals Online (AJOL)

    Multiplex polymerase chain reaction (PCR) was used for molecular typing of Salmonella enterica serovars in Egypt. During the summer of 2010, a total of 1075 samples were collected from cattle, sheep and poultry farms to be subjected for isolation of Salmonella (290 rectal swabs from cattle, 335 rectal swabs from sheep ...

  13. Salmonella infection acquired from reptilian pets.

    Science.gov (United States)

    Sanyal, D; Douglas, T; Roberts, R

    1997-10-01

    Two children presented with signs and symptoms of gastroenteritis. Salmonella chameleon was isolated from the stool of one child and also from an iguana kept in the home as a pet. Salmonella arizonae was isolated from the stool of the other child and also from four snakes sharing the same household. Exotic reptiles are unsuitable pets to share the home environment with infants.

  14. Salmonella in the lairage of pig slaughterhouses

    NARCIS (Netherlands)

    Swanenburg, M.; Urlings, H.A.P.; Keuzenkamp, D.A.; Snijders, J.M.A.

    2001-01-01

    The purpose of this study was to determine if lairages of pig slaughterhouses can act as a source of contamination of slaughtered pigs with Salmonella. The prevalence and variety of serotypes of Salmonella in the lairages of two pig slaughterhouses were determined, and the efficacy of the usual

  15. Interactions of Salmonella with animals and plants

    Directory of Open Access Journals (Sweden)

    Agnès eWiedemann

    2015-01-01

    Full Text Available Salmonella enterica species is a Gram negative bacterium, which is responsible for a wide range of food- and water-borne diseases in both humans and animals, thereby posing a major threat to public health. Recently, there has been an increasing number of reports, linking Salmonella contaminated raw vegetables and fruit with food poisoning. Many studies have shown that an essential feature of the pathogenicity of Salmonella is its capacity to cross a number of barriers requiring invasion of a large variety of cells and that the extent of internalization may be influenced by numerous factors. However, it is poorly understood how Salmonella successfully infects hosts as diversified as animals or plants. The aim of this review is to describe the different stages required for Salmonella interaction with its hosts: (i attachment to host surfaces; (ii entry processes; (iii, multiplication; (iv suppression of host defence mechanisms ; and to point out similarities and differences between animal and plant infections.

  16. Interactions of Salmonella with animals and plants.

    Science.gov (United States)

    Wiedemann, Agnès; Virlogeux-Payant, Isabelle; Chaussé, Anne-Marie; Schikora, Adam; Velge, Philippe

    2014-01-01

    Salmonella enterica species are Gram-negative bacteria, which are responsible for a wide range of food- and water-borne diseases in both humans and animals, thereby posing a major threat to public health. Recently, there has been an increasing number of reports, linking Salmonella contaminated raw vegetables and fruits with food poisoning. Many studies have shown that an essential feature of the pathogenicity of Salmonella is its capacity to cross a number of barriers requiring invasion of a large variety of cells and that the extent of internalization may be influenced by numerous factors. However, it is poorly understood how Salmonella successfully infects hosts as diversified as animals or plants. The aim of this review is to describe the different stages required for Salmonella interaction with its hosts: (i) attachment to host surfaces; (ii) entry processes; (iii) multiplication; (iv) suppression of host defense mechanisms; and to point out similarities and differences between animal and plant infections.

  17. Interactions of Salmonella with animals and plants

    Science.gov (United States)

    Wiedemann, Agnès; Virlogeux-Payant, Isabelle; Chaussé, Anne-Marie; Schikora, Adam; Velge, Philippe

    2015-01-01

    Salmonella enterica species are Gram-negative bacteria, which are responsible for a wide range of food- and water-borne diseases in both humans and animals, thereby posing a major threat to public health. Recently, there has been an increasing number of reports, linking Salmonella contaminated raw vegetables and fruits with food poisoning. Many studies have shown that an essential feature of the pathogenicity of Salmonella is its capacity to cross a number of barriers requiring invasion of a large variety of cells and that the extent of internalization may be influenced by numerous factors. However, it is poorly understood how Salmonella successfully infects hosts as diversified as animals or plants. The aim of this review is to describe the different stages required for Salmonella interaction with its hosts: (i) attachment to host surfaces; (ii) entry processes; (iii) multiplication; (iv) suppression of host defense mechanisms; and to point out similarities and differences between animal and plant infections. PMID:25653644

  18. Prevalence and antimicrobial resistance of Salmonella serovars isolated from poultry in Ghana

    DEFF Research Database (Denmark)

    Andoh, Linda A.; Dalsgaard, Anders; Obiri-Danso, K.

    2016-01-01

    Poultry are possible sources of non-typhoidal Salmonella serovars which may cause foodborne human disease. We conducted a cross-sectional study to determine the prevalence of Salmonella serovars in egg-laying hens and broilers at the farm level and their susceptibility to antimicrobials commonly...... of antimicrobials). Of the resistant strains (n = 57), the most significant were to nalidixic acid (89·5%), tetracycline (80·7%), ciprofloxacin (64·9%), sulfamethazole (42·1%), trimethoprim (29·8%) and ampicillin (26·3%). All S. Kentucky strains were resistant to more than two antimicrobials and shared common...

  19. Non-Typhoidal Salmonella Aortitis in a transplant patient

    International Nuclear Information System (INIS)

    Tarif, N.; Azam, M.N.; Mitwalli, Ahmad H.; Al-Wakeel, Jamal S.; El-Kheder, A. Al-Aboud

    2002-01-01

    Non-typhoidal salmonella bacteremia may result in extra gastrointestinallocalization of infection. Aortitis due to non-typhoidal salmonella wasreported to be the cause of 38-42% of all infected abdominal aortitis.Underlying atherosclerosis is a frequent site for salmonella aortitis. Wedescribe here a case of possible salmonella aortitis in a renal transplantpatient. (author)

  20. 9 CFR 113.123 - Salmonella Dublin Bacterin.

    Science.gov (United States)

    2010-01-01

    ... 9 Animals and Animal Products 1 2010-01-01 2010-01-01 false Salmonella Dublin Bacterin. 113.123... Inactivated Bacterial Products § 113.123 Salmonella Dublin Bacterin. Salmonella Dublin Bacterin shall be prepared from a culture of Salmonella dublin which has been inactivated and is nontoxic. Each serial of...

  1. 9 CFR 113.122 - Salmonella Choleraesuis Bacterin.

    Science.gov (United States)

    2010-01-01

    ... 9 Animals and Animal Products 1 2010-01-01 2010-01-01 false Salmonella Choleraesuis Bacterin. 113... REQUIREMENTS Inactivated Bacterial Products § 113.122 Salmonella Choleraesuis Bacterin. Salmonella Choleraesuis Bacterin shall be prepared from a culture of Salmonella choleraesuis which has been inactivated and is...

  2. 9 CFR 113.120 - Salmonella Typhimurium Bacterin.

    Science.gov (United States)

    2010-01-01

    ... 9 Animals and Animal Products 1 2010-01-01 2010-01-01 false Salmonella Typhimurium Bacterin. 113... REQUIREMENTS Inactivated Bacterial Products § 113.120 Salmonella Typhimurium Bacterin. Salmonella Typhimurium Bacterin shall be prepared from a culture of Salmonella typhimurium which has been inactivated and is...

  3. Identification of a Plasmid-Mediated Quinolone Resistance Gene in Salmonella Isolates from Texas Dairy Farm Environmental Samples.

    Science.gov (United States)

    Cummings, K J; Rodriguez-Rivera, L D; Norman, K N; Ohta, N; Scott, H M

    2017-06-01

    A recent increase in plasmid-mediated quinolone resistance (PMQR) has been detected among Salmonella isolated from humans in the United States, and it is necessary to determine the sources of human infection. We had previously isolated Salmonella from dairy farm environmental samples collected in Texas, and isolates were tested for anti-microbial susceptibility. Two isolates, serotyped as Salmonella Muenster, showed the discordant pattern of nalidixic acid susceptibility and intermediate susceptibility to ciprofloxacin. For this project, whole-genome sequencing of both isolates was performed to detect genes associated with quinolone resistance. The plasmid-mediated qnrB19 gene and IncR plasmid type were identified in both isolates. To our knowledge, this is the first report of PMQR in Salmonella isolated from food animals or agricultural environments in the United States. © 2016 Blackwell Verlag GmbH.

  4. Prevalence of antimicrobial resistance of non-typhoidal Salmonella serovars in retail aquaculture products.

    Science.gov (United States)

    Zhang, Jianmin; Yang, Xiaowei; Kuang, Dai; Shi, Xianming; Xiao, Wenjia; Zhang, Jing; Gu, Zhen; Xu, Xuebin; Meng, Jianghong

    2015-10-01

    Aquaculture products can become sources of Salmonella by exposure to contaminated water or through processing practices, thus representing a public health hazard. A study was conducted on Salmonella contamination in aquaculture products sampled from marketplaces and retailers in Shanghai, China. A total of 730 samples (including fish, shellfish, bullfrog, clam, shrimp and others) were obtained from 2006 to 2011. Among them, 217 (29.7%) were positive for Salmonella. Thirty-eight serovars were identified in the 217 Salmonella isolates. The most prevalent were Salmonella Aberdeen (18.4%), S. Wandsworth (12.0%), S. Thompson (9.2%), S. Singapore (5.5%), S. Stanley (4.6%), S. Schwarzengrund (4.6%), S. Hvittingfoss (4.1%) and S. Typhimurium (4.1%). Many resistant isolates were detected, with 69.6% resistant to at least one antimicrobial drug. We observed high resistance to sulfonamides (56.5%), tetracycline (34.1%), streptomycin (28.6%), ampicillin (23.5%) and nalidixic acid (21.2%). Lower levels of resistance were found for gentamicin (3.2%), ciprofloxacin (2.3%), ceftiofur (1.3%), cefotaxime (0.9%), ceftazidime (0.5%) and cefepime (0.5%). A total of 43.3% of the Salmonella isolates were multidrug-resistant and 44 different resistance patterns were found. This study provided data on the prevalence, serovars and antimicrobial resistance of Salmonella from retail aquaculture products in Shanghai, and indicated the need for monitoring programs for microbiologic safety in such projects and for more prudent drug use in aquaculture production in order to reduce the risk of development and spread of antimicrobial resistance. Copyright © 2015 Elsevier B.V. All rights reserved.

  5. Prevalence and Antimicrobial Resistance of Salmonella Isolates from Chicken Carcasses in Retail Markets in Yangon, Myanmar.

    Science.gov (United States)

    Moe, Aung Zaw; Paulsen, Peter; Pichpol, Duangporn; Fries, Reinhard; Irsigler, Herlinde; Baumann, Maximilian P O; Oo, Kyaw Naing

    2017-06-01

    A cross-sectional investigation was conducted concerning prevalence, antimicrobial resistance, multidrug resistance patterns, and serovar diversity of Salmonella in chicken meat sold at retail in Yangon, Myanmar. The 141 chicken meat samples were collected at 141 retail markets in the Yangon Region, Myanmar, 1 November 2014 to 31 March 2015. Information on hygienic practices (potential risk factors) was retrieved via checklists. Salmonella was isolated and identified according to International Organization for Standardization methods (ISO 6579:2002) with minor modifications. Twelve antimicrobial agents belonging to eight pharmacological groups were used for antimicrobial susceptibility testing (disk diffusion method). Salmonella was recovered from 138 (97.9%) of the 141 samples. The isolates were most frequently resistant to trimethoprim-sulfamethoxazole (70.3% of isolates), tetracycline (54.3%), streptomycin (49.3%), and ampicillin (47.1%). Resistance was also found to chloramphenicol (29.7%), amoxicillin-clavulanic acid (17.4%), ciprofloxacin (9.4%), tobramycin (8.7%), gentamicin (8%), cefazolin (7.2%), lincomycin-spectinomycin (5.8%), and norfloxacin (0.7%). Among the 138 Salmonella isolates, 72 (52.2%) were resistant to three or more antimicrobial agents. Twenty-four serovars were identified among the 138 Salmonella-positive samples; serovars Albany, Kentucky, Braenderup, and Indiana were found in 38, 11, 10, and 8% of samples, respectively. None of the potential risk factors were significantly related to Salmonella contamination of chicken carcasses. This study provides new information regarding prevalence and antimicrobial resistance and Salmonella serovar diversity in retail markets in Yangon, Myanmar.

  6. Serotypes and Antimicrobial Susceptibility of Salmonella spp. Isolated from Farm Animals in China

    Directory of Open Access Journals (Sweden)

    Yuan Zong Hui

    2015-06-01

    Full Text Available Salmonella spp. can indirectly infect humans via transfer from animals and animal-derived food products, and thereby cause potentially fatal diseases. Therefore, gaining an understanding of Salmonella infection in farm animals is increasingly important. The aim of this study was to identify the distribution of serotypes in Salmonella samples isolated from chickens (n = 837, pigs (n = 930, and dairy cows (n = 418 in central China (Henan, Hubei, and Hunan provinces in 2010–2011, and investigate the susceptibility of strains to antimicrobial agents. Salmonella isolates were identified by PCR amplification of the invA gene, serotypes were determined by using a slide agglutination test for O and H antigens, and susceptibility to 24 antimicrobials was tested using the agar dilution method. In total, 248 Salmonella strains were identified: 105, 105, and 38 from chickens, dairy cows, and pigs, respectively. Additionally, 209 strains were identified in unhealthy pigs from the Huazhong Agricultural University veterinary hospital. Among these 457 strains, the dominant serotypes were Typhimurium in serogroup B, IIIb in serogroup C, and Enteritidis in serogroup D. In antimicrobial susceptibility tests, 41.14% of Salmonella spp. were susceptible to all antimicrobial agents, 48.14% were resistant to at least one, and 34.72% were resistant to more than three classes. Strains were highly resistant to sulfamethoxazole-trimethoprim (39.61%, nalidixic acid (39.17%, doxycycline (28.22%, and tetracycline (27.58%. Resistance to cephalosporins and fluoroquinolones ranged from 5.25% to 7.44% and 19.04% to 24.51%, respectively. Among penicillin-resistant and cephalosporin-resistant strains, 25 isolates produced extended-spectrum β-lactamases (ESBLs. The multidrug-resistant and ESBL-producing Salmonella strains identified in healthy animals here will present a challenge for veterinary medicine and farm animal husbandry, and could also pose a threat to public health

  7. Prevalence, seasonal occurrence and antimicrobial resistance of Salmonella in poultry retail products in Greece.

    Science.gov (United States)

    Zdragas, A; Mazaraki, K; Vafeas, G; Giantzi, V; Papadopoulos, T; Ekateriniadou, L

    2012-10-01

    To detect the prevalence, the seasonal occurrence and distribution of Salmonella serotypes in poultry products and to determine the resistance profile of Salmonella isolates. A total of 96 skin-on chicken carcasses and 30 liver samples were analysed between May 2007 and May 2009 from twenty-two different commercial farm brands found in retail market countrywide. Salmonella was isolated from 38 (39·5%) of 96 chicken carcasses and from 10 (33·3%) of 30 liver samples. Higher isolation rate (60·4%) was observed in carcasses detected during summer (May to October), and lower isolation rate (18·7%) was observed in carcasses detected during winter (November to April); in liver samples, the positive rates were 53·4 and 13·2%, respectively. Twelve serotypes were detected with the serotypes Hadar, Enteritidis and Blockley being the most prevalent at 29·2, 22·9 and 12·5%, respectively. Nine of 11 Salm. Enteritidis isolates occurred during summer. Of 48 isolates, 38 (79%) were resistant to one or more of the antimicrobial agents used. The highest resistance rates were found to the following antimicrobials: streptomycin (64·5%), tetracycline (56·2%), nalidixic acid (39·5%), ampicillin and rifampicin (33·3%). The relatively high Salmonella spp. contamination rates of raw chicken meat and liver have been detected. Salm. Enteritidis isolates peaked in summer, increasing the risk to human health. Antibiotic resistance of Salmonella still remains a threat as resistance plasmids may be extensively shared between animal and humans. The study enabled us to improve the data on the seasonal occurrence of Salmonella and to determine the antimicrobial pattern profile and trends in Salmonella strains isolated from poultry retail products in Greece. © 2012 The Authors. Letters in Applied Microbiology © 2012 The Society for Applied Microbiology.

  8. Occurrence and antimicrobial susceptibility of Salmonella isolates recovered from the pig slaughter process in Romania.

    Science.gov (United States)

    Morar, Adriana; Sala, Claudia; Imre, Kálmán

    2015-01-15

    Reported human salmonellosis cases have increased in Romania. Antibiotic susceptibility testing of Salmonella strains isolated from pork and chicken meat indicate a worrying multidrug resistance pattern. This study aimed to investigate the occurrence of Salmonella and to evaluate the antibiotic resistance of Salmonella strains in a pig slaughterhouse-processing complex, which receives animals from 30% of the large industrialized swine farms in Romania. A total of 108 samples, including pork (n = 47), packaged pork products (n = 44), scald water sludge (n = 8), and detritus from the hair removal machine of the slaughterhouse (n = 9) were examined for the presence of Salmonella through standard methods. The antibiotic susceptibility of the isolated strains to 17 antibiotics was tested using the Vitek 2 system. Twenty-six (24.1%) samples were found to be Salmonella positive; this included 25.5% of meat samples and 15.9% of packaged products, as well as samples from two different points of the slaughter (41.2%). Resistance was observed against tetracycline (61.5%), ampicillin (50%), piperacillin (50%), trimethoprim-sulfamethoxazole (34.6%), amoxicillin/clavulanic acid (26.9%), nitrofurantion (23.1%), cefazolin (15.4%), piperacillin/tazobactam (7.7%), imipenem (3.8%), ciprofloxacin (3.8%), and norfloxacin (3.8%). No resistance towards cefoxitin, cefotaxime, ceftazidime, cefepime, amikacin, and gentamicin was found. Our study demonstrated the occurrence of multidrug-resistant Salmonella strains in the investigated pork production complex and highlighted it as a potential source of human infections. The results demonstrate the seriousness of antibiotic resistance of Salmonella in Romania, while providing a useful insight for the treatment of human salmonellosis by specialists.

  9. Revised Ciprofloxacin Breakpoints for Salmonella: Is it Time to Write an Obituary?

    Science.gov (United States)

    Girish, Revathy; Kumar, Anil; Khan, Sadia; Dinesh, Kavitha R; Karim, Shamsul

    2013-11-01

    To determine the minimum inhibitory concentration of ciprofloxacin among 50 blood stream isolates of Salmonella enterica. A total of 50 consecutive isolates of Salmonella enterica were tested for susceptibility to antimicrobials using the Kirby Bauer disk diffusion method. Minimum inhibitory concentrations were determined using Hi-Comb strips. All results were interpreted according to the CLSI guidelines. Of the 50 isolates 70%were Salmonella Typhi, 4% Salmonella paratyphi A, 2% Salmonella paratyphi B and the remaining 10% were identified only as Salmonella species. Using the CLSI 2011 breakpoints for disc diffusion, 86% (43/50) were resistant to nalidixic acid(NA), 22% (11/50) to ciprofloxacin, 12% to azithromycin, 6% to cotrimoxazole, 4% to ampicillin and 1% to chloramphenicol. The MIC50 and MIC90 of ciprofloxacin for S.Typhi were 0.181 μg/mL and 5.06 μg/mL respectively. While the same for S. paratyphi A was 0.212μg/mL and 0.228μg/mL respectively. None of the isolates were multi drug resistant and all were susceptible to ceftriaxone. Using the CLSI 2012 revised ciprofloxacin breakpoints for disc diffusion (>31mm) & MIC (<0.06 μg/mL), 90% (45/50) of these isolates were found to be resistant. MIC's of ciprofloxacin should be reported for all salmonella isolates and should be used to guide treatment. Blindly following western guidelines for a disease which is highly endemic in the subcontinent will spell the death knell of a cheap and effective drug in our armamentarium. Therefore it will be too premature to declare that "the concept of using ciprofloxacin in typhoid fever is dead!"

  10. A multiplex single nucleotide polymorphism typing assay for detecting mutations that result in decreased fluoroquinolone susceptibility in Salmonella enterica serovars Typhi and Paratyphi A.

    LENUS (Irish Health Repository)

    Song, Yajun

    2010-08-01

    OBJECTIVES: Decreased susceptibility to fluoroquinolones has become a major problem for the successful therapy of human infections caused by Salmonella enterica, especially the life-threatening typhoid and paratyphoid fevers. METHODS: By using Luminex xTAG beads, we developed a rapid, reliable and cost-effective multiplexed genotyping assay for simultaneously detecting 11 mutations in gyrA, gyrB and parE of S. enterica serovars Typhi and Paratyphi A that result in nalidixic acid resistance (Nal(R)) and\\/or decreased susceptibility to fluoroquinolones. RESULTS: This assay yielded unambiguous single nucleotide polymorphism calls on extracted DNA from 292 isolates of Salmonella Typhi (Nal(R) = 223 and Nal(S) = 69) and 106 isolates of Salmonella Paratyphi A (Nal(R) = 24 and Nal(S) = 82). All of the 247 Nal(R) Salmonella Typhi and Salmonella Paratyphi A isolates were found to harbour at least one of the target mutations, with GyrA Phe-83 as the most common one (143\\/223 for Salmonella Typhi and 18\\/24 for Salmonella Paratyphi A). We also identified three GyrB mutations in eight Nal(S) Salmonella Typhi isolates (six for GyrB Phe-464, one for GyrB Leu-465 and one for GyrB Asp-466), and mutations GyrB Phe-464 and GyrB Asp-466 seem to be related to the decreased ciprofloxacin susceptibility phenotype in Salmonella Typhi. This assay can also be used directly on boiled single colonies. CONCLUSIONS: The assay presented here would be useful for clinical and reference laboratories to rapidly screen quinolone-resistant isolates of Salmonella Typhi and Salmonella Paratyphi A, and decipher the underlying genetic changes for epidemiological purposes.

  11. Splenic abscesses from Salmonella infection

    International Nuclear Information System (INIS)

    Gomez, Carmen Cecilia; Zuniga Eduardo

    2005-01-01

    Spleen abscesses are uncommon. We describe the case of a 56 year-old man who presented with diarrhea, fever, vomiting and weight loss. On physical examination, the main findings included jaundice, hepatomegaly and ascites. Diagnostic imaging showed the presence of spleen abscesses, due to Salmonella species. Considering the type of abscess, medical treatment was given without the need for interventional treatment, resulting in a satisfactory outcome. No other risk factor was found, other than the gastrointestinal focus as the precursor of the splenic abscess.

  12. Incidence of Salmonella Infantis in poultry meat and products and the resistance of isolates to antimicrobials

    Science.gov (United States)

    Kalaba, V.; Golić, B.; Sladojević, Ž.; Kalaba, D.

    2017-09-01

    Globalisation, climate change, changes in eating habits and the food industry, modern animal husbandry and market demands often have a negative impact on quality assurance, food safety and animal health. After the eradication of some zoonotic diseases that previously often jeopardized the human population, today in developed countries, the focus is mainly on the control of zoonoses transmitted by food. Salmonella is one of the most common pathogens that can be transmitted from animals to humans, and its reservoirs are poultry, cattle and pigs, so one transmission route to humans is from contaminated food of animal origin. Multidrug-resistant isolates of Salmonella, which can transfer their resistance genes to other microorganisms, are considered a serious threat to public health. Control of Salmonella primarily depends on a good monitoring system and knowledge of the presence of serovars and strains in an epizootiological area. During the first nine months of 2016, 1321 samples of poultry meat and products were examined, among which 108 harboured Salmonella. Altogether, 29 of the 108 isolates (26.85%) were Salmonella Infantis. For all 29 S. Infantis isolates, antimicrobial resistance was tested by the disc diffusion method. The isolates showed 100% resistance to amoxicillin, and nalidixic acid.

  13. Yerba mate enhances probiotic bacteria growth in vitro but as a feed additive does not reduce Salmonella Enteritidis colonization in vivo.

    Science.gov (United States)

    Gonzalez-Gil, Francisco; Diaz-Sanchez, Sandra; Pendleton, Sean; Andino, Ana; Zhang, Nan; Yard, Carrie; Crilly, Nate; Harte, Federico; Hanning, Irene

    2014-02-01

    Yerba mate (Ilex paraguariensis) is a tea known to have beneficial effects on human health and antimicrobial activity against some foodborne pathogens. Thus, the application of yerba mate as a feed additive for broiler chickens to reduce Salmonella colonization was evaluated. The first in vitro evaluation was conducted by suspending Salmonella Enteritidis and lactic acid bacteria (LAB) in yerba mate extract. The in vivo evaluations were conducted using preventative and horizontal transmission experiments. In all experiments, day-of-hatch chicks were treated with one of the following 1) no treatment (control); 2) ground yerba mate in feed; 3) probiotic treatment (Lactobacillus acidophilus and Pediococcus; 9:1 administered once on day of hatch by gavage); or 4) both yerba mate and probiotic treatments. At d 3, all chicks were challenged with Salmonella Enteritidis (preventative experiment) or 5 of 20 chicks (horizontal transmission experiment). At d 10, all birds were euthanized, weighed, and cecal contents enumerated for Salmonella. For the in vitro evaluation, antimicrobial activity was observed against Salmonella and the same treatment enhanced growth of LAB. For in vivo evaluations, none of the yerba mate treatments significantly reduced Salmonella Enteritidis colonization, whereas the probiotic treatment significantly reduced Salmonella colonization in the horizontal transmission experiment. Yerba mate decreased chicken BW and decreased the performance of the probiotic treatment when used in combination. In conclusion, yerba mate had antimicrobial activity against foodborne pathogens and enhanced the growth of LAB in vitro, but in vivo yerba mate did not decrease Salmonella Enteritidis colonization.

  14. A dual mechanism involved in membrane and nucleic acid disruption of AvBD103b, a new avian defensin from the king penguin, against Salmonella enteritidis CVCC3377.

    Science.gov (United States)

    Teng, Da; Wang, Xiumin; Xi, Di; Mao, Ruoyu; Zhang, Yong; Guan, Qingfeng; Zhang, Jun; Wang, Jianhua

    2014-10-01

    The food-borne bacterial gastrointestinal infection is a serious public health threat. Defensins are evolutionarily conserved innate immune components with broad-spectrum antibacterial activity that do not easily induce resistance. AvBD103b, an avian defensin with potent activity against Salmonella enteritidis, was isolated from the stomach contents of the king penguin (Aptenodytes patagonicus). To elucidate further the antibacterial mechanism of AvBD103b, its effect on the S. enteritidis CVCC3377 cell membrane and intracellular DNA was researched. The cell surface hydrophobicity and a N-phenyl-1-naphthylamine uptake assay demonstrated that AvBD103b treatment increased the cell surface hydrophobicity and outer membrane permeability. Atomic absorption spectrometry, ultraviolet spectrophotometry, flow cytometry, and transmission electron microscopy (TEM) indicated that AvBD103b treatment can lead to the release of the cellular contents and cell death through damage of the membrane. DNA gel retardation and circular dichroism analysis demonstrated that AvBD103b interacted with DNA and intercalated into the DNA base pairs. A cell cycle assay demonstrated that AvBD103b affected cellular functions, such as DNA synthesis. Our results confirmed that AvBD103b exerts its antibacterial activity by damaging the cell membrane and interfering with intracellular DNA, ultimately causing cell death, and suggested that AvBD103b may be a promising candidate as an alternative to antibiotics against S. enteritidis.

  15. Survival of Salmonella enterica in poultry feed is strain dependent.

    Science.gov (United States)

    Andino, Ana; Pendleton, Sean; Zhang, Nan; Chen, Wei; Critzer, Faith; Hanning, Irene

    2014-02-01

    Feed components have low water activity, making bacterial survival difficult. The mechanisms of Salmonella survival in feed and subsequent colonization of poultry are unknown. The purpose of this research was to compare the ability of Salmonella serovars and strains to survive in broiler feed and to evaluate molecular mechanisms associated with survival and colonization by measuring the expression of genes associated with colonization (hilA, invA) and survival via fatty acid synthesis (cfa, fabA, fabB, fabD). Feed was inoculated with 1 of 15 strains of Salmonella enterica consisting of 11 serovars (Typhimurium, Enteriditis, Kentucky, Seftenburg, Heidelberg, Mbandanka, Newport, Bairely, Javiana, Montevideo, and Infantis). To inoculate feed, cultures were suspended in PBS and survival was evaluated by plating samples onto XLT4 agar plates at specific time points (0 h, 4 h, 8 h, 24 h, 4 d, and 7 d). To evaluate gene expression, RNA was extracted from the samples at the specific time points (0, 4, 8, and 24 h) and gene expression measured with real-time PCR. The largest reduction in Salmonella occurred at the first and third sampling time points (4 h and 4 d) with the average reductions being 1.9 and 1.6 log cfu per g, respectively. For the remaining time points (8 h, 24 h, and 7 d), the average reduction was less than 1 log cfu per g (0.6, 0.4, and 0.6, respectively). Most strains upregulated cfa (cyclopropane fatty acid synthesis) within 8 h, which would modify the fluidity of the cell wall to aid in survival. There was a weak negative correlation between survival and virulence gene expression indicating downregulation to focus energy on other gene expression efforts such as survival-related genes. These data indicate the ability of strains to survive over time in poultry feed was strain dependent and that upregulation of cyclopropane fatty acid synthesis and downregulation of virulence genes were associated with a response to desiccation stress.

  16. Salmonella radicidation of poultry carcasses

    International Nuclear Information System (INIS)

    Mulder, R.W.A.W.

    1982-01-01

    This thesis reports investigations using gamma-radiation to decontaminate poultry carcasses. The application to foods of doses of ionizing radiation sufficient to reduce the number of viable specific non-sporeforming pathogenic microorganisms so that none is detectable in the treated food by any standard method is termed radicidation. The doses used in this study were at such a level that no undesirable or unfavourable side-effects occurred. The effects of these doses were studied on salmonellae and other microorganisms present in, or associated with poultry carcasses and in liquid and on solid culture media as well. Decimal reduction (D 10 ) values were estimated. These represent the dose (kGy) required to achieve a reduction in initial colony count from N 0 to 0.1 N 0 . Together with the estimation of the numbers of Salmonella present per carcass the data were used to predict the effect of an ionizing radiation treatment of poultry. Data on the effect of ionizing radiation on the total microflora of poultry carcasses were also collected. (Auth.)

  17. Evaluation of Modification of the 3M™ Molecular Detection Assay (MDA) Salmonella Method (2013.09) for the Detection of Salmonella in Selected Foods: Collaborative Study.

    Science.gov (United States)

    Bird, Patrick; Fisher, Kiel; Boyle, Megan; Huffman, Travis; Benzinger, M Joseph; Bedinghaus, Paige; Flannery, Jonathon; Crowley, Erin; Agin, James; Goins, David; Benesh, DeAnn; David, John

    2014-01-01

    The 3M(™) Molecular Detection Assay (MDA) Salmonella utilizes isothermal amplification of nucleic acid sequences with high specificity, efficiency, rapidity and bioluminescence to detect amplification of Salmonella spp. in food, food-related, and environmental samples after enrichment. A method modification and matrix extension study of the previously approved AOAC Official Method(SM) 2013.09 was conducted, and approval of the modification was received on March 20, 2014. Using an unpaired study design in a multilaboratory collaborative study, the 3M MDA Salmonella method was compared to the U.S. Department of Agriculture/Food Safety and Inspection Service (USDA/FSIS) Microbiology Laboratory Guidebook (MLG) 4.05 (2011), Isolation and Identification of Salmonella from Meat, Poultry, Pasteurized Egg, and Catfish Products for raw ground beef and the U.S. Food and Drug Administration (FDA)/Bacteriological Analytical Manual (BAM) Chapter 5, Salmonella reference method for wet dog food following the current AOAC guidelines. A total of 20 laboratories participated. For the 3M MDA Salmonella method, raw ground beef was analyzed using 25 g test portions, and wet dog food was analyzed using 375 g test portions. For the reference methods, 25 g test portions of each matrix were analyzed. Each matrix was artificially contaminated with Salmonella at three inoculation levels: an uninoculated control level (0 CFU/test portion), a low inoculum level (0.2-2 CFU/test portion), and a high inoculum level (2-5 CFU/test portion). In this study, 1512 unpaired replicate samples were analyzed. Statistical analysis was conducted according to the probability of detection (POD). For the low-level raw ground beef test portions, the following dLPOD (difference between the LPODs of the reference and candidate method) values with 95% confidence intervals were obtained: -0.01 (-0.14, +0.12). For the low-level wet dog food test portions, the following dLPOD with 95% confidence intervals were

  18. Survival of Salmonella Newport in oysters.

    Science.gov (United States)

    Morrison, Christopher M; Armstrong, Alexandra E; Evans, Sanford; Mild, Rita M; Langdon, Christopher J; Joens, Lynn A

    2011-08-02

    Salmonella enterica is the leading cause of laboratory-confirmed foodborne illness in the United States and raw shellfish consumption is a commonly implicated source of gastrointestinal pathogens. A 2005 epidemiological study done in our laboratory by Brands et al., showed that oysters in the United States are contaminated with Salmonella, and in particular, a specific strain of the Newport serovar. This work sought to further investigate the host-microbe interactions between Salmonella Newport and oysters. A procedure was developed to reliably and repeatedly expose oysters to enteric bacteria and quantify the subsequent levels of bacterial survival. The results show that 10 days after an exposure to Salmonella Newport, an average concentration of 3.7 × 10(3)CFU/g remains within the oyster meat, and even after 60 days there still can be more than 10(2)CFU/g remaining. However, the strain of Newport that predominated in the market survey done by Brands et al. does not survive within oysters or the estuarine environment better than any other strains of Salmonella we tested. Using this same methodology, we compared Salmonella Newport's ability to survive within oysters to a non-pathogenic strain of E. coli and found that after 10 days the concentration of Salmonella was 200-times greater than that of E. coli. We also compared those same strains of Salmonella and E. coli in a depuration process to determine if a constant 120 L/h flux of clean seawater could significantly reduce the concentration of bacteria within oysters and found that after 3 days the oysters retained over 10(4)CFU/g of Salmonella while the oysters exposed to the non-pathogenic strain of E. coli contained 100-times less bacteria. Overall, the results of this study demonstrate that any of the clinically relevant serovars of Salmonella can survive within oysters for significant periods of time after just one exposure event. Based on the drastic differences in survivability between Salmonella and a non

  19. Pleural Empyema due to Group D Salmonella

    Directory of Open Access Journals (Sweden)

    Jennifer C. Kam

    2012-01-01

    Full Text Available Non-typhi Salmonella normally presents as a bacteremia, enterocolitis, and endovascular infection but rarely manifests as pleuropulmonary disease. We present a case of a 66-year-old female with underlying pulmonary pathology, secondary to an extensive smoking history, who presented with a left-sided pleural effusion. The causative agent was identified as being group D Salmonella. Decortication of the lung was performed and the patient was discharged on antibiotics with resolution of her symptoms. This case helps to support the inclusion of Salmonella group D as a possible etiological agent of infection in the differential causes of exudative pleural effusions.

  20. Denaturing Gradient Gel Electrophoresis-Polymerase Chain Reaction Comparison of Chitosan Effects on Anaerobic Cultures of Broiler Cecal Bacteria and Salmonella Typhimurium.

    Science.gov (United States)

    Hume, Michael; Sohail, Muhammad Umar

    2018-04-01

    Enteropathogen colonization and product contamination are major poultry industry problems. The emergence of antibiotic resistance, and associated risks to human health, is limiting the use of antibiotics as first-line defense against enteropathogens in poultry. The chitin derivative, chitosan, has drawn substantial attention for its bactericidal properties. Different molecular weight (MW) chitosans can have varied effects against different bacteria in monoculture. In the current study, cecal contents from each of three market-age broilers and Salmonella Typhimurium, as indicator enteropathogen, were exposed to in vitro anaerobic culture to three chitosan preparations (0.08%, wt/vol), low (LMW), medium (MMW), and coarse (CMW). Effects of chitosan and the carrier solvent acetic acid, on cecal bacteria and Salmonella, were examined by denaturing gradient gel electrophoresis (DGGE) and Salmonella enumeration. Bacterial profiles for the three cecal contents were shown by DGGE to be very different. Each of the three cecal contents grown in the presence of 0.08% acetic acid was very different from the same contents grown without the chitosan solvent. Culturing cecal contents in the presence of chitosan altered the bacterial DGGE profiles from the control and acetic acid-only cultures. The DGGE chitosan-treated profiles for all three cecal sources were identical to each other regardless of the MW chitosan in the culture medium. Compared with Salmonella in monoculture, Salmonella decreased (p < 0.05) by about 1.5 log CFU/mL when grown in mixed culture with cecal contents. Salmonella monocultures in the presence of 0.08% of the chitosan solvent acetic acid decreased (p < 0.05) counts by almost 3.5 log CFU/mL. Combining acetic acid and cecal contents reduced (p < 0.05) Salmonella by 7 log CFU/mL. Adding the chitosan preparations to the mixtures reduced (p < 0.05) Salmonella by 8 log CFU/mL.

  1. The tenth CRL-Salmonella workshop; 28 and 29 April 2005, Bilthoven, the Netherlands

    NARCIS (Netherlands)

    Mooijman KA; MGB

    2006-01-01

    De tiende workshop georganiseerd door het Communautair Referentie Laboratorium voor Salmonella (CRL-Salmonella) werd gehouden op 28 en 29 April 2005 in Bilthoven, Nederland. Deelnemers betroffen vertegenwoordigers van de Nationale Referentie Laboratoria voor Salmonella (NRLs-Salmonella) van de

  2. Comparative genomics of the lactic acid bacteria

    Energy Technology Data Exchange (ETDEWEB)

    Makarova, K.; Slesarev, A.; Wolf, Y.; Sorokin, A.; Mirkin, B.; Koonin, E.; Pavlov, A.; Pavlova, N.; Karamychev, V.; Polouchine, N.; Shakhova, V.; Grigoriev, I.; Lou, Y.; Rokhsar, D.; Lucas, S.; Huang, K.; Goodstein, D. M.; Hawkins, T.; Plengvidhya, V.; Welker, D.; Hughes, J.; Goh, Y.; Benson, A.; Baldwin, K.; Lee, J. -H.; Diaz-Muniz, I.; Dosti, B.; Smeianov, V; Wechter, W.; Barabote, R.; Lorca, G.; Altermann, E.; Barrangou, R.; Ganesan, B.; Xie, Y.; Rawsthorne, H.; Tamir, D.; Parker, C.; Breidt, F.; Broadbent, J.; Hutkins, R.; O' Sullivan, D.; Steele, J.; Unlu, G.; Saier, M.; Klaenhammer, T.; Richardson, P.; Kozyavkin, S.; Weimer, B.; Mills, D.

    2006-06-01

    Lactic acid-producing bacteria are associated with various plant and animal niches and play a key role in the production of fermented foods and beverages. We report nine genome sequences representing the phylogenetic and functional diversity of these bacteria. The small genomes of lactic acid bacteria encode a broad repertoire of transporters for efficient carbon and nitrogen acquisition from the nutritionally rich environments they inhabit and reflect a limited range of biosynthetic capabilities that indicate both prototrophic and auxotrophic strains. Phylogenetic analyses, comparison of gene content across the group, and reconstruction of ancestral gene sets indicate a combination of extensive gene loss and key gene acquisitions via horizontal gene transfer during the coevolution of lactic acid bacteria with their habitats.

  3. Inactivation of Listeria monocytogenes, Escherichia coli O157:H7, and Salmonella typhimurium with compounds available in households.

    Science.gov (United States)

    Yang, Hua; Kendall, Patricia A; Medeiros, Lydia; Sofos, John N

    2009-06-01

    Solutions of selected household products were tested for their effectiveness against Listeria monocytogenes, Escherichia coli O157:H7, and Salmonella Typhimurium. Hydrogen peroxide (1.5 and 3%), vinegar (2.5 and 5% acetic acid), baking soda (11, 33, and 50% sodium bicarbonate), household bleach (0.0314, 0.0933, and 0.670% sodium hypochlorite), 5% acetic acid (prepared from glacial acetic acid), and 5% citric acid solutions were tested against the three pathogens individually (five-strain composites of each, 10(8) CFU/ml) by using a modified AOAC International suspension test at initial temperatures of 25 and 55degrees C for 1 and 10 min. All bleach solutions (pH 8.36 to 10.14) produced a >5-log reduction of all pathogens tested after 1 min at 25 degrees C, whereas all baking soda solutions (pH 7.32 to 7.55) were ineffective (5-log reduction of both Salmonella Typhimurium and E. coli O157:H7, whereas undiluted vinegar (pH 2.58) had a similar effect only against Salmonella Typhimurium. Compared with 1 min at 25 degrees C, greater reductions of L. monocytogenes (P 3% hydrogen peroxide > undiluted vinegar and 5% acetic acid > 5% citric acid > baking soda (50% sodium bicarbonate). The sensitivity of the tested pathogens to all tested household compounds followed the sequence of Salmonella Typhimurium > E. coli O157: H7 > L. monocytogenes.

  4. PREVALENCE OF SALMONELLA IN CAPTIVE REPTILES FROM CROATIA.

    Science.gov (United States)

    Lukac, Maja; Pedersen, Karl; Prukner-Radovcic, Estella

    2015-06-01

    Salmonellosis transmitted by pet reptiles is an increasing public health issue worldwide. The aim of this study was to investigate the prevalence of Salmonella strains from captive reptiles in Croatia. From November 2009 to November 2011 a total of 292 skin, pharyngeal, cloacal, and fecal samples from 200 apparently healthy reptiles were tested for Salmonella excretions by bacteriologic culture and serotyping. These 200 individual reptiles included 31 lizards, 79 chelonians, and 90 snakes belonging to private owners or housed at the Zagreb Zoo, Croatia. Salmonella was detected in a total of 13% of the animals, among them 48.4% lizards, 8.9% snakes, and 3.8% turtles. Representatives of five of the six Salmonella enterica subspecies were identified with the following proportions in the total number of isolates: Salmonella enterica enterica 34.6%, Salmonella enterica houtenae 23.1%, Salmonella enterica arizonae 23.1%, Salmonella enterica diarizonae 15.4%, and Salmonella enterica salamae 3.8%. The 14 different serovars isolated included several rarely occurring serovars such as Salmonella Apapa, Salmonella Halle, Salmonella Kisarawe, and Salmonella Potengi. These findings confirm that the prevalence of Salmonella is considerable in captive reptiles in Croatia, indicating that these animals may harbor serovars not commonly seen in veterinary or human microbiologic practice. This should be addressed in the prevention and diagnostics of human reptile-transmitted infections.

  5. Antimicrobial resistance trends among Salmonella isolates obtained from horses in the northeastern United States (2001-2013).

    Science.gov (United States)

    Cummings, Kevin J; Perkins, Gillian A; Khatibzadeh, Sarah M; Warnick, Lorin D; Aprea, Victor A; Altier, Craig

    2016-05-01

    OBJECTIVE To describe the antimicrobial resistance patterns of Salmonella isolates obtained from horses in the northeastern United States and to identify trends in resistance to select antimicrobials over time. SAMPLE 462 Salmonella isolates from horses. PROCEDURES Retrospective data were collected for all Salmonella isolates obtained from equine specimens that were submitted to the Cornell University Animal Health Diagnostic Center between January 1, 2001, and December 31, 2013. Temporal trends in the prevalence of resistant Salmonella isolates were investigated for each of 13 antimicrobials by use of the Cochran-Armitage trend test. RESULTS The prevalence of resistant isolates varied among antimicrobials and ranged from 0% (imipenem) to 51.5% (chloramphenicol). During the observation period, the prevalence of resistant isolates decreased significantly for amoxicillin-clavulanic acid, ampicillin, cefazolin, cefoxitin, ceftiofur, chloramphenicol, and tetracycline and remained negligible for amikacin and enrofloxacin. Of the 337 isolates for which the susceptibility to all 13 antimicrobials was determined, 138 (40.9%) were pansusceptible and 192 (57.0%) were multidrug resistant (resistant to ≥ 3 antimicrobial classes). The most common serovar isolated was Salmonella Newport, and although the annual prevalence of that serovar decreased significantly over time, that decrease had only a minimal effect on the observed antimicrobial resistance trends. CONCLUSIONS AND CLINICAL RELEVANCE Results suggested that current antimicrobial use in horses is not promoting the emergence and dissemination of antimicrobial-resistant Salmonella strains in the region served by the laboratory.

  6. Influence of Natural Organic Matter on Attachment Kinetics of Salmonella Typhimurium

    Science.gov (United States)

    Chowdhury, I.; Zorlu, O.; Hill, J. E.; Walker, S. L.

    2011-12-01

    Salmonella enterica serovar Typhimurium is one of the most common and virulent bacterial pathogens, usually found in food and water. This waterborne pathogen has been attributed to causing gastroenteritis and typhoid fever, leading to 16 million cases and over half a million deaths worldwide each year. Natural organic matter (NOM) is ubiquitous in environment and previous work has shown NOM to enhance the stability and transport of bacteria cells; hence NOM will certainly interact with Salmonella and affect its transport in environment. The objective of this study was to investigate the influence of NOM (Suwannee River humic acid standard II, SRHA) on the attachment kinetics of a model Salmonella (Salmonella enterica serovar Typhimurium SA5983) to glass. The transport study was conducted in a parallel plate flow chamber using fluorescent microscope to visualize the bacterial cells, which were tagged with green fluorescent protein (GFP). The solution pH was unadjusted, and the flow rate through parallel plate channel was 0.1 mL/min to simulate groundwater conditions. Parameters varied in this study were NOM presence, ion valence (K+, Ca2+) as well as cell growth phase (mid-exponential and late-exponential growth phases). These parameters were chosen because ion valence may alter the NOM conformation and capacity for bridging, as well growth phase impacts the cellular surface chemistry. Extensive characterization of the bacterial cells was conducted including measurements of electrophoretic mobility, hydrophobicity, acidity, surface charge density and extracellular polymeric substance content. Additionally, electrokintic characterization was conducted for the glass. Preliminary results demonstrated the sensitivity of cell attachment to ionic valence and cell growth phase. Also the addition of NOM reduced the attachment of the Salmonella cells significantly under all of these conditions. Without NOM, attachment efficiencies (α) in KCl were similar at both growth

  7. antimicrobial susceptibility pattern of Salmonella species

    African Journals Online (AJOL)

    user

    GLOBAL JOURNAL OF COMMUNITY MEDICINE VOL. 2 NO. 1 & 2 2009: 5 - ... This study is a review of the contemporary antimicrobial susceptibility pattern of. Salmonella species. ... south-east Asia, parts of Latin America, the. Caribbean, and ...

  8. Elimination of salmonella from animal glandular products.

    Science.gov (United States)

    De Fiebre, C W; Burck, K T; Feldman, D

    1969-03-01

    Methods for the elimination of salmonellae from selected powdered pharmaceuticals of animal glandular origin were studied. Terminal heat treatment under carefully controlled conditions was effective for pancreatin-a powder containing proteolytic, amylolytic, and lipolytic enzymes prepared from hog pancreas glands. Use of this method resulted in a significant reduction in the number of salmonella-positive batches and also reduced the testing procedures required to confirm the absence of viable salmonellae among the majority of samples tested. Powders such as stomach substance and thyroid, in which the biological activity is not enzyme in nature, were treated successfully with acidified organic solvents. Other methods were investigated but were not suitable because of a deleterious effect on the biological activity or physical properties of the product or an inability to effect salmonella elimination.

  9. Elimination of Salmonellae from Animal Glandular Products

    Science.gov (United States)

    De Fiebre, Conrad W.; Burck, Kenneth T.; Feldman, David

    1969-01-01

    Methods for the elimination of salmonellae from selected powdered pharmaceuticals of animal glandular origin were studied. Terminal heat treatment under carefully controlled conditions was effective for pancreatin—a powder containing proteolytic, amylolytic, and lipolytic enzymes prepared from hog pancreas glands. Use of this method resulted in a significant reduction in the number of salmonella-positive batches and also reduced the testing procedures required to confirm the absence of viable salmonellae among the majority of samples tested. Powders such as stomach substance and thyroid, in which the biological activity is not enzyme in nature, were treated successfully with acidified organic solvents. Other methods were investigated but were not suitable because of a deleterious effect on the biological activity or physical properties of the product or an inability to effect salmonella elimination. PMID:5780395

  10. Antibiotic susceptibilities of Salmonella species prevalent among ...

    African Journals Online (AJOL)

    Arun Kumar Agnihotri

    2016-03-21

    Mar 21, 2016 ... The highest incidence was observed in children of 13-24 ... incidence of Salmonella and continued health education of ..... until it formed a homogenous suspension. ..... Salvador, Bahia, Brazil. .... Lagos University Teaching.

  11. The Salmonella enterica Pan-genome

    DEFF Research Database (Denmark)

    Jacobsen, Annika; Hendriksen, Rene S.; Aarestrup, Frank Møller

    2011-01-01

    Salmonella enterica is divided into four subspecies containing a large number of different serovars, several of which are important zoonotic pathogens and some show a high degree of host specificity or host preference. We compare 45 sequenced S. enterica genomes that are publicly available (22......, and the core and pan-genome of Salmonella were estimated to be around 2,800 and 10,000 gene families, respectively. The constructed pan-genomic dendrograms suggest that gene content is often, but not uniformly correlated to serotype. Any given Salmonella strain has a large stable core, whilst...... there is an abundance of accessory genes, including the Salmonella pathogenicity islands (SPIs), transposable elements, phages, and plasmid DNA. We visualize conservation in the genomes in relation to chromosomal location and DNA structural features and find that variation in gene content is localized in a selection...

  12. A carbon nanotube immunosensor for Salmonella

    Science.gov (United States)

    Lerner, Mitchell B.; Goldsmith, Brett R.; McMillon, Ronald; Dailey, Jennifer; Pillai, Shreekumar; Singh, Shree R.; Johnson, A. T. Charlie

    2011-12-01

    Antibody-functionalized carbon nanotube devices have been suggested for use as bacterial detectors for monitoring of food purity in transit from the farm to the kitchen. Here we report progress towards that goal by demonstrating specific detection of Salmonella in complex nutrient broth solutions using nanotube transistors functionalized with covalently-bound anti-Salmonella antibodies. The small size of the active device region makes them compatible with integration in large-scale arrays. We find that the on-state current of the transistor is sensitive specifically to the Salmonella concentration and saturates at low concentration (Salmonella and other bacteria types, with no sign of saturation even at much larger concentrations (108 cfu/ml).

  13. The occurrence of Salmonella in airline meals.

    Science.gov (United States)

    Hatakka, M; Asplund, K

    1993-01-01

    The occurrence of Salmonella in airline meals was studied in 1989-1992. Samples were collected from flight kitchens in 29 countries. The material consisted of 400 cold dishes and 1,288 hot dishes as well as salads, cheese plates and deserts. Total number of samples was 2211. Salmonella spp. were isolated from 6 samples; 1 contaminated sample was a cold dish prepared in Bangkok, 1 was a hot dish prepared in Mombasa and the remaining 4 contaminated samples were hot dishes prepared within one week in Beijing. The isolated serotypes were S. ohio, S. manchester and S. braenderup. The contaminated cold dish prepared by a flight kitchen in Bangkok was found to be connected with a Salmonella outbreak which occurred in Finland in 1990. Cold airline dishes containing food of animal origin seems to be more risky as a source of Salmonella infections among airline passengers.

  14. Radiosensitivity study of salmonella enteritidis in chickens

    International Nuclear Information System (INIS)

    Fernandez Gianotti, Tomas

    1997-01-01

    One of the applications of ionizing radiations in food is the inactivation of vegetative phatogenic bacteria (radicidation) such as Salmonella, Shigella, Campylobacter, Vibro and Listeria. These bacteria are associated with the diseases transmitted by food (ETA). Fresh and frozen farmyard fowls can be contaminated with pathogenic microorganisms, between them Salmonella. In Argentine, between years 1987-1990, Salmonella enteritidis was the main cause of salmonellosis. In food irradiation, with the aim of improving and assuring its hygienic quality, it is important to know the radiosensitivity of microorganisms to be inactivated. Inactivation of a determined microorganism shall depend, between others factors, of the species, strain, number and of the irradiation conditions (temperature, media, etc.). D 10 value is a very useful data in order to compare radiosensitivities between the microorganisms and the influence of different factors in their sensitivities. In this paper, it was determined the sensitivity to the gamma radiation of Salmonella enteritidis in fresh and frozen chickens

  15. Molecular study on some antibiotic resistant genes in Salmonella spp. isolates

    Science.gov (United States)

    Nabi, Ari Q.

    2017-09-01

    Studying the genes related with antimicrobial resistance in Salmonella spp. is a crucial step toward a correct and faster treatment of infections caused by the pathogen. In this work Integron mediated antibiotic resistant gene IntI1 (Class I Integrase IntI1) and some plasmid mediated antibiotic resistance genes (Qnr) were scanned among the isolated non-Typhoid Salmonellae strains with known resistance to some important antimicrobial drugs using Sybr Green real time PCR. The aim of the study was to correlate the multiple antibiotics and antimicrobial resistance of Salmonella spp. with the presence of integrase (IntI1) gene and plasmid mediated quinolone resistant genes. Results revealed the presence of Class I Integrase gene in 76% of the isolates with confirmed multiple antibiotic resistances. Moreover, about 32% of the multiple antibiotic resistant serotypes showed a positive R-PCR for plasmid mediated qnrA gene encoding for nalidixic acid and ciprofloxacin resistance. No positive results could be revealed form R-PCRs targeting qnrB or qnrS. In light of these results we can conclude that the presence of at least one of the qnr genes and/or the presence of Integrase Class I gene were responsible for the multiple antibiotic resistance to for nalidixic acid and ciprofloxacin from the studied Salmonella spp. and further studies required to identify the genes related with multiple antibiotic resistance of the pathogen.

  16. Identification and Characterization of Outer Membrane Vesicle-Associated Proteins in Salmonella enterica Serovar Typhimurium

    Science.gov (United States)

    Bai, Jaewoo; Kim, Seul I; Ryu, Sangryeol

    2014-01-01

    Salmonella enterica serovar Typhimurium is a primary cause of enteric diseases and has acquired a variety of virulence factors during its evolution into a pathogen. Secreted virulence factors interact with commensal flora and host cells and enable Salmonella to survive and thrive in hostile environments. Outer membrane vesicles (OMVs) released from many Gram-negative bacteria function as a mechanism for the secretion of complex mixtures, including virulence factors. We performed a proteomic analysis of OMVs that were isolated under standard laboratory and acidic minimal medium conditions and identified 14 OMV-associated proteins that were observed in the OMV fraction isolated only under the acidic minimal medium conditions, which reproduced the nutrient-deficient intracellular milieu. The inferred roles of these 14 proteins were diverse, including transporter, enzyme, and transcriptional regulator. The absence of these proteins influenced Salmonella survival inside murine macrophages. Eleven of these proteins were predicted to possess secretion signal sequences at their N termini, and three (HupA, GlnH, and PhoN) of the proteins were found to be translocated into the cytoplasm of host cells. The comparative proteomic profiling of OMVs performed in this study revealed different protein compositions in the OMVs isolated under the two different conditions, which indicates that the OMV cargo depends on the growth conditions and provides a deeper insight into how Salmonella utilizes OMVs to adapt to environmental changes. PMID:24935973

  17. Dissemination of Zoonotic Antibiotic Resistant Serotypes of Salmonella by Caspian Pond Turtles, Golestan and Mazandaran Provinces, Iran

    Directory of Open Access Journals (Sweden)

    Somayeh Namroodi

    2017-03-01

    Full Text Available Background: Salmonella spp. are widespread zoonotic pathogens with economic importance for both humans and animals. They are categorized as the natural flora of the gastrointestinal tract of many reptiles. Human salmonellosis acquired from contact with reptiles is a well-recognized medical problem. Objective: The frequency of Salmonella contamination in Caspian pond turtles was surveyed to evaluate the danger of exposure or disease risk for humans as these species are abundant around the villages in Golestan and Mazandaran provinces. Materials and Methods: One hundred fifty fecal samples from Caspian pond turtles were tested by standard bacteriological methods and positive samples were serotyped. Antimicrobial susceptibility tests on isolated Salmonella strains were also performed. Results: Out of 150 samples, 54 turtles were detected to be contaminated with Salmonella. Of the 54 Salmonella isolates, 38.8% (21/54 were serotyped as S. typhimurium; 35.1% (19/54 as S. enterica subsp. enterica; 9.2% (5/54 as S. enterica subsp. salamae; 9.2% (5/54 as S. enterica subsp. arizona; and 7.4% (4/54 as S. enterica subsp. houtenae. Female (28/80, 35% and male (26/74, 35.1% turtles showed equal incidence of Salmonella spp. contamination. Resistance was mostly observed against ampicillin (37% followed by tetracycline (33.3%, nalidixic acid (7.4%, ciprofloxacin (5.5%, and cotrimoxazole (3.7%. The highest susceptibility was observed against gentamicin (100% and trimethoprim (98.1%. Conclusion: Our findings confirmed that people who are in close exposure to Caspian pond turtles and their feces are at the risk of Salmonella contamination. Accordingly, fundamental principles of hygiene should be applied in human contact with Caspian pond turtles. Furthermore, people should be educated about the Salmonella contamination which may occur through Caspian pond turtles.

  18. Experimental reproduction of rotavirus and Salmonella pullorum ...

    African Journals Online (AJOL)

    Group A chicks were inoculated with 1 X 106 pfu/ml of rotavirus, group B chicks were inoculated with 1 X 106 cfu/ml of Salmonella pullorum, group C chicks were inoculated with 1 X 106 pfu/ml of rotavirus and 1 X 106 cfu/ml of Salmonella pullorum, while group D birds were given 1ml of PBS alone. Birds in all groups were ...

  19. Salmonella in beef and produce from honduras.

    Science.gov (United States)

    Maradiaga, Martha; Miller, Mark F; Thompson, Leslie; Pond, Ansen; Gragg, Sara E; Echeverry, Alejandro; Garcia, Lyda G; Loneragan, Guy H; Brashears, Mindy M

    2015-03-01

    Salmonella continues to cause a considerable number of foodborne illnesses worldwide. The sources of outbreaks include contaminated meat and produce. The purpose of this study was to establish an initial investigation of the burden of Salmonella in produce and beef from Honduras by sampling retail markets and abattoirs. Retail produce samples (cantaloupes, cilantro, cucumbers, leafy greens, peppers, and tomatoes; n = 573) were purchased in three major cities of Honduras, and retail whole-muscle beef (n = 555) samples were also purchased in four major cities. Additionally, both hide and beef carcass (n = 141) samples were collected from two Honduran abattoirs. Whole-muscle beef samples were obtained using a sponge hydrated with buffered peptone water, and 10 ml of the buffered peptone water rinsate of each produce sample was collected with a dry sponge and placed in a bag to be transported back to the United States. Salmonella was detected using a commercially available, closeplatform PCR system, and positive samples were subjected to culture on selective media to obtain isolates. Overall, the prevalence of Salmonella-positive samples, based on PCR detection in Honduras (n = 555) retail beef was 10.1% (95% confidence interval = 7.8, 12.9), whereas 7.8% (n = 141) of beef carcass and hides samples were positive in both beef plants. The overall Salmonella prevalence for all produce samples (n = 573) collected was 2.1% (95% confidence interval = 1.2, 3.6). The most common serotypes identified in Honduras were Salmonella Typhimurium followed by Derby. These results provide an indication of Salmonella contamination of beef and produce in Honduras. Developing a Salmonella baseline for Latin America through an initial investigation like the one presented here contributes to a broader global understanding of the potential exposure through food, thus providing insight into the needs for control strategies.

  20. lac repressor is an antivirulence factor of Salmonella enterica: its role in the evolution of virulence in Salmonella.

    Directory of Open Access Journals (Sweden)

    Sandeepa M Eswarappa

    Full Text Available The genus Salmonella includes many pathogens of great medical and veterinary importance. Bacteria belonging to this genus are very closely related to those belonging to the genus Escherichia. lacZYA operon and lacI are present in Escherichia coli, but not in Salmonella enterica. It has been proposed that Salmonella has lost lacZYA operon and lacI during evolution. In this study, we have investigated the physiological and evolutionary significance of the absence of lacI in Salmonella enterica. Using murine model of typhoid fever, we show that the expression of LacI causes a remarkable reduction in the virulence of Salmonella enterica. LacI also suppresses the ability of Salmonella enterica to proliferate inside murine macrophages. Microarray analysis revealed that LacI interferes with the expression of virulence genes of Salmonella pathogenicity island 2. This effect was confirmed by RT-PCR and Western blot analysis. Interestingly, we found that SBG0326 of Salmonella bongori is homologous to lacI of Escherichia coli. Salmonella bongori is the only other species of the genus Salmonella and it lacks the virulence genes of Salmonella pathogenicity island 2. Overall, our results demonstrate that LacI is an antivirulence factor of Salmonella enterica and suggest that absence of lacI has facilitated the acquisition of virulence genes of Salmonella pathogenicity island 2 in Salmonella enterica making it a successful systemic pathogen.

  1. Tentative Colistin Epidemiological Cut-Off Value for Salmonella spp

    DEFF Research Database (Denmark)

    Agersø, Yvonne; Torpdahl, Mia; Zachariasen, Camilla

    2012-01-01

    . Interestingly, Salmonella Dublin and Salmonella Enteritidis belong to the same O-group (O:1, 9,12), suggesting that surface lipopolysaccharides (LPS) of the cell (O-antigen) play a role in colistin susceptibility. The epidemiological cut-off value of >2 mg/L for colistin suggested by European Committee...... on Antimicrobial Susceptibility Testing (EUCAST) is placed inside the distribution for both Salmonella Dublin and Salmonella Enteritidis. All tested Salmonella Dublin isolates, regardless of MIC colistin value, had identical pmrA and pmrB sequences. Missense mutations were found only in pmrA in one Salmonella...

  2. Isolation and Determination of Antibiotic Resistance Patterns in Nontyphoid Salmonella spp isolated from chicken

    Directory of Open Access Journals (Sweden)

    Seyyedeh Hoorieh Fallah

    2013-01-01

    Full Text Available Background: Salmonellosis is one of the most common food borne diseases in industrial and developing countries. In recent years, an increase in antimicrobial drug resistance, among non-typhoid Salmonella spp has been observed. Objectives: The aim of this study was to isolate and determine antibiotic resistance pattern in non-typhoid Salmonella spp. Materials and Methods: This descriptive study was done on 100 samples of chickens collected from 196 retail markets and was examined for the presence of Salmonella using standard bacteriological procedures and stereotyping kit. Antimicrobial susceptibility testing was performed by disk diffusion methods according to the National Committee for Clinical Laboratory Standards (CLSI. The data were analyzed by using the SPSS software version 18. Result: Forty- four percent of samples were contaminated with Salmonella infection and 56% didn’t have any contamination. The stereotyping results showed that 34 of 44 isolates of Salmonella belonged to Salmonella infantis (79.5 %, one strain (2.3% of group C and 8 strain (18.2% of group D. However, all these strains were sensitive to Cefotaxime and Ciprofloxacin, and 100% were resistant to Nalidixic acid, Tetracyclin and Sterptomycin. The most common resistance pattern (34.1% was towards six antibiotics, and 6.8% of strains were resistant to at least three antibiotics. Conclusion: High levels of resistance to antibiotics that are used commonly for human and poultry can be a warning for our community health and this information must be used to form important strategies for improvement of infection control.

  3. Diversity and antimicrobial resistance of Salmonella enterica isolates from surface water in Southeastern United States.

    Science.gov (United States)

    Li, Baoguang; Vellidis, George; Liu, Huanli; Jay-Russell, Michele; Zhao, Shaohua; Hu, Zonglin; Wright, Anita; Elkins, Christopher A

    2014-10-01

    A study of prevalence, diversity, and antimicrobial resistance of Salmonella enterica in surface water in the southeastern United States was conducted. A new scheme was developed for recovery of Salmonella from irrigation pond water and compared with the FDA's Bacteriological Analytical Manual (8th ed., 2014) (BAM) method. Fifty-one isolates were recovered from 10 irrigation ponds in produce farms over a 2-year period; nine Salmonella serovars were identified by pulsed-field gel electrophoresis analysis, and the major serovar was Salmonella enterica serovar Newport (S. Newport, n = 29), followed by S. enterica serovar Enteritidis (n = 6), S. enterica serovar Muenchen (n = 4), S. enterica serovar Javiana (n = 3), S. enterica serovar Thompson (n = 2), and other serovars. It is noteworthy that the PulseNet patterns of some of the isolates were identical to those of the strains that were associated with the S. Thompson outbreaks in 2010, 2012, and 2013, S. Enteritidis outbreaks in 2011 and 2013, and an S. Javiana outbreak in 2012. Antimicrobial susceptibility testing confirmed 16 S. Newport isolates of the multidrug resistant-AmpC (MDR-AmpC) phenotype, which exhibited resistance to ampicillin, chloramphenicol, streptomycin, sulfamethoxazole, and tetracycline (ACSSuT), and to the 1st, 2nd, and 3rd generations of cephalosporins (cephalothin, amoxicillin-clavulanic acid, and ceftriaxone). Moreover, the S. Newport MDR-AmpC isolates had a PFGE pattern indistinguishable from the patterns of the isolates from clinical settings. These findings suggest that the irrigation water may be a potential source of contamination of Salmonella in fresh produce. The new Salmonella isolation scheme significantly increased recovery efficiency from 21.2 (36/170) to 29.4% (50/170) (P = 0.0002) and streamlined the turnaround time from 5 to 9 days with the BAM method to 4 days and thus may facilitate microbiological analysis of environmental water. Copyright © 2014, American Society for

  4. Plasma-treated polyethylene film: A smart material applied for Salmonella Typhimurium detection

    Energy Technology Data Exchange (ETDEWEB)

    Peng-Ubol, Triranat [Department of Chemistry, Faculty of Science, Mahidol University, Rama 6 Rd, Phayathai, Bangkok 10400 (Thailand); Phinyocheep, Pranee, E-mail: scppo@mahidol.ac.th [Department of Chemistry, Faculty of Science, Mahidol University, Rama 6 Rd, Phayathai, Bangkok 10400 (Thailand); Daniel, Philippe [Laboratoire de Physique de l' Etat Condense (LPEC-UMR CNRS 6087), Universite du Maine, Avenue Olivier Messiaen, 72085, Le Mans Cedex 9 (France); Panbangred, Watanalai [Department of Biotechnology and Mahidol University-Osaka University Collaborative Research Center for Bioscience and Biotechnology (MU-OU: CRC), Faculty of Science, Mahidol University, Rama 6 Rd, Phayathai, Bangkok 10400 (Thailand); Pilard, Jean-Francois [Unite de Chimie Organique Moleculaire et Macromoleculaire (UCO2M-UMR CNRS 6011), Universite du Maine, Avenue Olivier Messiaen, 72085 Le Mans Cedex 9 (France); Thouand, Gerald; Durand-Thouand, Marie-Jose [Genie des Procedes Environnement et Agroalimentaire (GEPEA UMR CNRS 6144), Departement Genie Biologique, IUT de la Roche/Yon, Universite de Nantes, 18 Bd G. Defferre, 85035 La Roche sur Yon (France)

    2012-12-01

    Salmonella is a major cause of foodborne illness worldwide and is not allowed to be present in any food in all countries. The purpose of this study is to develop a simple alternative method for the detection of Salmonella based on functionalized polyethylene (PE) surfaces. Salmonella Typhimurium was used as a model bacterium. PE film was treated using dielectric plasma in order to alter the wettability of the PE surface and consequently introduce functionality on the surface. The PE film characterized by ATR-FTIR spectroscopy revealed the presence of C=O stretching of ketones, aldehydes and carboxylic acids. The antibodies against O or H antigens of Salmonella and S. Typhimurium were then respectively immobilized on the PE surface after activation of the carboxylic group using NHS/EDC followed by protein A. The evidences from ATR-FTIR, scanning electron microscopy and optical microscopy showed the presence of S. Typhimurium attached to the plasma treated PE surfaces via the two types of anti-Salmonella antibody. The plasma treated PE film developed is simple and allows efficient association of bacterial cells on the treated surfaces without the necessity of time-consuming centrifugation and washing steps for isolation of the cells. This material is considered to be a smart material applicable for S. Typhimurium detection. Highlights: Black-Right-Pointing-Pointer We developed a functionalized polyethylene film for bacterial detection. Black-Right-Pointing-Pointer We modified the surface of polyethylene film by plasma treatment. Black-Right-Pointing-Pointer ATR-FTIR spectroscopy was used to analyze the functionality on the PE surface. Black-Right-Pointing-Pointer We introduced Salmonella Typhimurium on the modified PE film. Black-Right-Pointing-Pointer SEM revealed the presence of S. Typhimurium on the plasma treated PE film.

  5. Plasma-treated polyethylene film: A smart material applied for Salmonella Typhimurium detection

    International Nuclear Information System (INIS)

    Peng-Ubol, Triranat; Phinyocheep, Pranee; Daniel, Philippe; Panbangred, Watanalai; Pilard, Jean-François; Thouand, Gerald; Durand-Thouand, Marie-José

    2012-01-01

    Salmonella is a major cause of foodborne illness worldwide and is not allowed to be present in any food in all countries. The purpose of this study is to develop a simple alternative method for the detection of Salmonella based on functionalized polyethylene (PE) surfaces. Salmonella Typhimurium was used as a model bacterium. PE film was treated using dielectric plasma in order to alter the wettability of the PE surface and consequently introduce functionality on the surface. The PE film characterized by ATR-FTIR spectroscopy revealed the presence of C=O stretching of ketones, aldehydes and carboxylic acids. The antibodies against O or H antigens of Salmonella and S. Typhimurium were then respectively immobilized on the PE surface after activation of the carboxylic group using NHS/EDC followed by protein A. The evidences from ATR-FTIR, scanning electron microscopy and optical microscopy showed the presence of S. Typhimurium attached to the plasma treated PE surfaces via the two types of anti-Salmonella antibody. The plasma treated PE film developed is simple and allows efficient association of bacterial cells on the treated surfaces without the necessity of time-consuming centrifugation and washing steps for isolation of the cells. This material is considered to be a smart material applicable for S. Typhimurium detection. Highlights: ► We developed a functionalized polyethylene film for bacterial detection. ► We modified the surface of polyethylene film by plasma treatment. ► ATR-FTIR spectroscopy was used to analyze the functionality on the PE surface. ► We introduced Salmonella Typhimurium on the modified PE film. ► SEM revealed the presence of S. Typhimurium on the plasma treated PE film.

  6. Efficacy of disinfectants and detergents intended for a pig farm environment where Salmonella is present.

    Science.gov (United States)

    Gosling, Rebecca J; Mawhinney, Ian; Vaughan, Kelly; Davies, Robert H; Smith, Richard P

    2017-05-01

    Disinfection is a useful component of disease control, although products and chemical groups vary in their activity against different pathogens. This study investigated the ability of fifteen disinfectants to eliminate pig-associated Salmonella. Active compounds of products included chlorocresol, glutaraldehyde/formaldehyde, glutaraldehyde/quaternary ammonium compounds (QAC), iodine, peracetic acid and potassium peroxomonosulphate. Six detergents were also tested for their ability to dislodge faecal material, and interactions with specific disinfectants. Eight serovars were screened against all products using dilution tests and a monophasic Salmonella Typhimurium strain was selected for further testing. The disinfectants were tested using models to replicate boot dip (faecal suspension) and animal housing (surface contamination) disinfection respectively at the Department for Environment, Food and Rural Affairs Approved Disinfectant General Orders (GO) concentration, half GO and twice GO. Stability over time and ability to eliminate Salmonella in biofilm was also assessed. The most effective products were then field tested. Most products at GO concentration eliminated Salmonella in the faecal suspension model. One glutaraldehyde/QAC and one glutaraldehyde/formaldehyde-based product at GO concentration eliminated Salmonella in the surface contamination model. Chlorocresol-based products were more stable in the faecal suspension model. One chlorocresol and the glutaraldehyde/formaldehyde-based product were most successful in eliminating Salmonella from biofilms. All products tested on farm reduced bacterial log counts; the glutaraldehyde/QAC based product produced the greatest reduction. The type of product and the application concentration can impact on efficacy of farm disinfection; therefore, clearer guidance is needed to ensure the appropriate programmes are used for specific environments. Crown Copyright © 2017. Published by Elsevier B.V. All rights reserved.

  7. Impact of litter Salmonella status during feed withdrawal on Salmonella recovery from the broiler crop and ceca.

    Science.gov (United States)

    Buhr, R J; Bourassa, D V; Hinton, A; Fairchild, B D; Ritz, C W

    2017-12-01

    Research was conducted to evaluate the impact of litter Salmonella status during feed withdrawal on Salmonella recovery from the crop and ceca following feed withdrawal. In 4 experiments, pens of broilers in separate rooms were challenged with marker strains of either Salmonella Montevideo or Salmonella Heidelberg. Three d post challenge, a 12-hour feed withdrawal was initiated, and one pen of broilers was switched between rooms for each Salmonella serotype. In experiments 3 and 4, non-challenged broilers also were added to the Salmonella challenge pens. The litter of each pen was sampled before and after the feed withdrawal period, the broilers euthanized, and the crop and ceca aseptically removed for Salmonella isolation. Results showed that only the challenge Salmonella serotype was recovered from the litter in challenge pens where broilers were not moved, while both Salmonella serotypes were recovered from the litter of the switched pens. Salmonella was recovered from 56/80 crops and from 66/80 ceca of challenged broilers that remained in the challenge pens. The challenge Salmonella serotype was recovered from 50/80 crops and from 60/80 ceca, and the switched pens' litter Salmonella serotype was recovered from 19/80 crops but not from the ceca in broilers challenged with Salmonella and then switched between pens. For experiments 3 and 4, Salmonella was recovered from 19/40 crops and from only 2/40 ceca from the non-challenged broilers placed into the Salmonella challenge pens. The results from broilers that were switched between Salmonella challenge pens indicate that the recovery of Salmonella from the crop of broilers following feed withdrawal (on Salmonella-contaminated litter) appears to depend mainly on the initial challenge Salmonella (62%) and less on the litter Salmonella (24%) status during the feed withdrawal period. In contrast, only the initial challenge Salmonella was recovered from the ceca (79%) from broilers that remained in challenge pens or

  8. Optimizing buffering chemistry to maintain near neutral pH of broiler feed during pre-enrichment for Salmonella.

    Science.gov (United States)

    Berrang, M E; Cosby, D E; Cox, N A; Cason, J A; Richardson, K E

    2015-12-01

    Salmonella is a human pathogen that can accompany live broilers to the slaughter plant, contaminating fully processed carcasses. Feed is one potential source of Salmonella to growing broilers. Monitoring feed for the presence of Salmonella is part of good agricultural practice. The first step in culturing feed for Salmonella (which may be at low numbers and sub-lethally stressed) is to add it to a pre-enrichment broth which is incubated for 24 h. During the course of pre-enrichment, extraneous bacteria metabolize carbohydrates in some feed and excrete acidic byproducts, causing the pH to drop dramatically. An acidic pre-enrichment pH can injure or kill Salmonella resulting in a failure to detect, even if it is present and available to infect chickens. The objective of this study was to test an array of buffering chemistries to prevent formation of an injurious acidic environment during pre-enrichment of feed in peptone water. Five grams of feed were added to 45 mL of peptone water buffered with carbonate, Tris pH 8, and phosphate buffering ingredients individually and in combination. Feed was subjected to a pre-enrichment at 35°C for 24 h; pH was measured at 0, 18, and 24 h. Standard phosphate buffering ingredients at concentrations up to 4 times the normal formulation were unable to fully prevent acidic conditions. Likewise, carbonate and Tris pH 8 were not fully effective. The combination of phosphate, carbonate, and Tris pH 8 was the most effective buffer tested. It is recommended that a highly buffered pre-enrichment broth be used to examine feed for the presence of Salmonella. Published by Oxford University Press on behalf of Poultry Science Association 2015. This work is written by (a) US Government employee(s) and is in the public domain in the US.

  9. Influence of On-farm pig Salmonella status on Salmonella Shedding at Slaughter.

    Science.gov (United States)

    Casanova-Higes, A; Andrés-Barranco, S; Mainar-Jaime, R C

    2017-08-01

    The risk of Salmonella shedding among pigs at slaughter with regard to their previous on-farm Salmonella status was assessed in a group of pigs from a farm from NE of Spain. A total of 202 pigs that had been serologically monitored monthly during the fattening period and from which mesenteric lymph nodes (MLN) and faecal (SFEC) samples were collected at slaughter for Salmonella isolation were included. A repeated-measures anova was used to assess the relationship between mean OD% values during the fattening period and sampling time and bacteriology on MLN and SFEC. Pigs were also grouped into four groups, that is pigs seronegative during the fattening period and Salmonella negative in MLN (group A; n = 69); pigs seronegative during the fattening period but Salmonella positive in MLN (B; n = 36); pigs seropositive at least once and Salmonella positive in MLN (C; n = 50); and pigs seropositive at least once but Salmonella negative in (D; n = 47). Pigs shedding at slaughter seroconverted much earlier and showed much higher mean OD% values than non-shedders pigs. The proportion of Salmonella shedders in groups A and D was high and similar (26.1% and 29.8%, respectively), but significantly lower than that for groups B and C. The odds of shedding Salmonella for groups B and C were 4.8 (95% CI = 1.5-15.5) and 20.9 (3.7-118) times higher, respectively, when compared to A. It was concluded that a large proportion of Salmonella seronegative pigs may shed Salmonella at slaughter, which would be likely associated to previous exposure with contaminated environments (i.e. transport and lairage). For pigs already infected at farm, the likelihood of shedding Salmonella was much higher and may depend on whether the bacterium has colonized the MLN or not. The odds of shedding Salmonella spp. were always much higher for pigs in which Salmonella was isolated from MLN. © 2016 Blackwell Verlag GmbH.

  10. Rapid detection of Salmonella in pet food: design and evaluation of integrated methods based on real-time PCR detection.

    Science.gov (United States)

    Balachandran, Priya; Friberg, Maria; Vanlandingham, V; Kozak, K; Manolis, Amanda; Brevnov, Maxim; Crowley, Erin; Bird, Patrick; Goins, David; Furtado, Manohar R; Petrauskene, Olga V; Tebbs, Robert S; Charbonneau, Duane

    2012-02-01

    Reducing the risk of Salmonella contamination in pet food is critical for both companion animals and humans, and its importance is reflected by the substantial increase in the demand for pathogen testing. Accurate and rapid detection of foodborne pathogens improves food safety, protects the public health, and benefits food producers by assuring product quality while facilitating product release in a timely manner. Traditional culture-based methods for Salmonella screening are laborious and can take 5 to 7 days to obtain definitive results. In this study, we developed two methods for the detection of low levels of Salmonella in pet food using real-time PCR: (i) detection of Salmonella in 25 g of dried pet food in less than 14 h with an automated magnetic bead-based nucleic acid extraction method and (ii) detection of Salmonella in 375 g of composite dry pet food matrix in less than 24 h with a manual centrifugation-based nucleic acid preparation method. Both methods included a preclarification step using a novel protocol that removes food matrix-associated debris and PCR inhibitors and improves the sensitivity of detection. Validation studies revealed no significant differences between the two real-time PCR methods and the standard U.S. Food and Drug Administration Bacteriological Analytical Manual (chapter 5) culture confirmation method.

  11. Prevalence and antimicrobial profiles of Salmonella serovars from ...

    African Journals Online (AJOL)

    ADEYEYE

    2014-01-21

    Jan 21, 2014 ... Presumptive Salmonella isolates were determined by using the conventional ... Salmonella represents a major contaminant of vegetables consumed in Maiduguri, North-eastern ... serovars in vegetables in Nigeria do not exist.

  12. Reduction of Salmonella in ground chicken using a bacteriophage.

    Science.gov (United States)

    Grant, Ar'Quette; Parveen, Salina; Schwarz, Jurgen; Hashem, Fawzy; Vimini, Bob

    2017-08-01

    This study's goal was to ascertain the effectiveness of a commercially available Salmonella bacteriophage during ground chicken production focusing on: water source, different Salmonella serovars, and time. Salmonella-free boneless, skinless chicken meat was inoculated with 4.0 Log CFU/cm2 of either a cocktail of 3 Salmonella isolates derived from ground chicken (GC) or a cocktail of 3 Salmonella strains not isolated from ground chicken (non-GC). Bacteriophages were spread onto the chicken using sterile tap or filtered water for 30 min or 8 h. Salmonella was recovered using standard plating method. Greater Salmonella reduction was observed when the bacteriophage was diluted in sterile tap water than in sterile filtered water: 0.39 Log CFU/cm2 and 0.23 Log CFU/cm2 reduction after 30 min, respectively (P Salmonella's susceptibility to the bacteriophage, and treatment time. © 2017 Poultry Science Association Inc.

  13. Autophagy Facilitates Salmonella Replication in HeLa Cells

    Science.gov (United States)

    Yu, Hong B.; Croxen, Matthew A.; Marchiando, Amanda M.; Ferreira, Rosana B. R.; Cadwell, Ken; Foster, Leonard J.; Finlay, B. Brett

    2014-01-01

    ABSTRACT Autophagy is a process whereby a double-membrane structure (autophagosome) engulfs unnecessary cytosolic proteins, organelles, and invading pathogens and delivers them to the lysosome for degradation. We examined the fate of cytosolic Salmonella targeted by autophagy and found that autophagy-targeted Salmonella present in the cytosol of HeLa cells correlates with intracellular bacterial replication. Real-time analyses revealed that a subset of cytosolic Salmonella extensively associates with autophagy components p62 and/or LC3 and replicates quickly, whereas intravacuolar Salmonella shows no or very limited association with p62 or LC3 and replicates much more slowly. Replication of cytosolic Salmonella in HeLa cells is significantly decreased when autophagy components are depleted. Eventually, hyperreplication of cytosolic Salmonella potentiates cell detachment, facilitating the dissemination of Salmonella to neighboring cells. We propose that Salmonella benefits from autophagy for its cytosolic replication in HeLa cells. PMID:24618251

  14. Synthesis of 6-Phosphofructose Aspartic Acid and Some Related Amadori Compounds

    OpenAIRE

    Hansen, Alexandar L.; Behrman, Edward J.

    2016-01-01

    We describe the synthesis and characterization of 6-phosphofructose-aspartic acid, an intermediate in the metabolism of fructose-asparagine by Salmonella. We also report improved syntheses of fructose-asparagine itself and of fructose-aspartic acid.

  15. Applications of microscopy in Salmonella research.

    Science.gov (United States)

    Malt, Layla M; Perrett, Charlotte A; Humphrey, Suzanne; Jepson, Mark A

    2015-01-01

    Salmonella enterica is a Gram-negative enteropathogen that can cause localized infections, typically resulting in gastroenteritis, or systemic infection, e.g., typhoid fever, in humans and many other animals. Understanding the mechanisms by which Salmonella induces disease has been the focus of intensive research. This has revealed that Salmonella invasion requires dynamic cross-talk between the microbe and host cells, in which bacterial adherence rapidly leads to a complex sequence of cellular responses initiated by proteins translocated into the host cell by a type 3 secretion system. Once these Salmonella-induced responses have resulted in bacterial invasion, proteins translocated by a second type 3 secretion system initiate further modulation of cellular activities to enable survival and replication of the invading pathogen. Elucidation of the complex and highly dynamic pathogen-host interactions ultimately requires analysis at the level of single cells and single infection events. To achieve this goal, researchers have applied a diverse range of microscopy techniques to analyze Salmonella infection in models ranging from whole animal to isolated cells and simple eukaryotic organisms. For example, electron microscopy and high-resolution light microscopy techniques such as confocal microscopy can reveal the precise location of Salmonella and its relationship to cellular components. Widefield light microscopy is a simpler approach with which to study the interaction of bacteria with host cells and often has advantages for live cell imaging, enabling detailed analysis of the dynamics of infection and cellular responses. Here we review the use of imaging techniques in Salmonella research and compare the capabilities of different classes of microscope to address specific types of research question. We also provide protocols and notes on some microscopy techniques used routinely in our own research.

  16. Test results of Salmonella typing by the National Reference Laboratories for Salmonella in the Member States of the European Union and the EnterNet Laboratories - Collaborative study VII on typing of Salmonella

    NARCIS (Netherlands)

    Korver H; Maas HME; Ward LR; Wannet WJB; Henken AM; MGB; LIS

    2003-01-01

    Het Communautair Referentie Laboratorium voor Salmonella (CRL-Salmonella, Bilthoven, Nederland) organiseerde in samenwerking met Public Health Laboratory Services (PHLS), London, Verenigd Koninkrijk een zevende ringonderzoek aangaande de typering van Salmonella. Zeventien Nationale Referentie

  17. Test results of Salmonella typing by the NRLs-Salmonella in the Member States of the EU and the EnterNet Laboratories - Collaborative study VI on typing of Salmonella

    NARCIS (Netherlands)

    Korver H; Raes M; Maas HME; Ward LR; Wannet WJB; Henken AM; MGB; LIS

    2002-01-01

    Test resultaten van Salmonella sero- en faagtypering en antimicrobiele gevoeligheidsbepalingen door de Nationale Referentie Laboratoria voor Salmonella in de Lidstaten van de Europese Unie en EnterNet Laboratoria: Ringonderzoek VI (2001) voor Salmonella. Een zesde ringonderzoek betreffende de

  18. Physical size of the donor locus and transmission of Haemophilus influenzae ampicillin resistance genes by deoxyribonucleic acid-mediated transformation

    International Nuclear Information System (INIS)

    Bendler, J.W. III

    1976-01-01

    The properties of donor deoxyribonucleic acid (DNA) from three clinical isolates and its ability to mediate the transformation of competent Rd strains to ampicillin resistance were examined. A quantitative technique for determining the resistance of individual Haemophilus influenzae cells to ampicillin was developed. When this technique was used, sensitive cells failed to tolerate levels of ampicillin greater than 0.1 to 0.2 μg/ml, whereas three resistant type b β-lactamase-producing strains could form colonies 1- to 3-μg/ml levels of the antibiotic. DNA extracted from the resistant strains elicited transformation of the auxotrophic genes in a multiply auxotrophic Rd strain. For two of the donors, transformation to ampicillin resistance occurred after the uptake of a single DNA molecule approximately 10 4 -fold less frequently than transformation of auxotrophic loci and was not observed to occur at all with the third. The frequency of transformation to ampicillin resistance was two- to fivefold higher in strain BC200 (Okinaka and Barnhart, 1974), which was cured of a defective prophage. All three clinical ampicillin-resistant strains were poor recipients, but the presence of the ampicillin resistant genes in strain BC200 did not reduce its competence

  19. Bilateral breast abscesses due to Salmonella Enterica serotype typhi

    Directory of Open Access Journals (Sweden)

    Gagandeep Singh

    2011-01-01

    Full Text Available Focal infection is an uncommon complication of Salmonella septicemia, particularly in immunocompetent patients. The localization of Salmonella infection to breast tissue is regarded as a rare event. We report a case of bilateral breast abscesses due to Salmonella enterica serotype Typhi in a nonlactating female and highlight the fact that Salmonella spp. should be included in differential diagnosis of abscesses in individuals coming from endemic areas with the history of recent typhoid fever and should be treated accordingly.

  20. Detection and classification of salmonella serotypes using spectral signatures collected by fourier transform infrared (FT-IR) spectroscopy

    Science.gov (United States)

    Spectral signatures of Salmonella serotypes namely Salmonella Typhimurium, Salmonella Enteritidis, Salmonella Infantis, Salmonella Heidelberg and Salmonella Kentucky were collected using Fourier transform infrared spectroscopy (FT-IR). About 5-10 µL of Salmonella suspensions with concentrations of 1...

  1. Diffuse abdominal gallium-67 citrate uptake in salmonella infections

    International Nuclear Information System (INIS)

    Garty, I.; Koren, A.

    1987-01-01

    Two pediatric patients with salmonella infections (one with typhoid fever and the second with salmonella C2 gastroenteritis), had a diffuse abdominal uptake of Ga-67 citrate. The possible explanation for this finding is discussed. Salmonella infection should be included as a cause in the differential diagnosis of diffuse accumulation of Ga-67 citrate

  2. 9 CFR 113.30 - Detection of Salmonella contamination.

    Science.gov (United States)

    2010-01-01

    ... 9 Animals and Animal Products 1 2010-01-01 2010-01-01 false Detection of Salmonella contamination... REQUIREMENTS Standard Procedures § 113.30 Detection of Salmonella contamination. The test for detection of Salmonella contamination provided in this section shall be conducted when such a test is prescribed in an...

  3. Salmonella Typhimurium pneumonia in a patient with multiple myeloma.

    Science.gov (United States)

    Khan, Sadia; Kumar, V Anil; Sidharthan, Neeraj; Mehta, Asmita; Backer, Binita; Dinesh, Kavitha R

    2015-04-01

    Pneumonia due to non-typhoidal Salmonella is a rarely reported entity. A fatal case of Salmonella pneumonia is reported here where Salmonella Typhimurium was isolated from the endotracheal aspirate and blood culture. © The Author(s) 2014 Reprints and permissions: sagepub.co.uk/journalsPermissions.nav.

  4. Detection of Salmonella typhi agglutinins in sera of patients with ...

    African Journals Online (AJOL)

    Background and Purpose: Widal test is frequently applied for the detection of Salmonella agglutinins to diagnose Salmonella enterica serotype Typhi infection. There are however a number of controversies challenging the diagnostic utility of this test. This study was performed to determine the prevalence of Salmonella ...

  5. Characterization of a multidrug resistant Salmonella enterica give ...

    African Journals Online (AJOL)

    Salmonella enterica Give is one of the serotypes that have been incriminated in Salmonella infections; sometimes associated with hospitalization and mortalities in humans and animals in some parts of the world. In this work, we characterized one Salmonella Give isolated from cloaca swab of an Agama agama lizard ...

  6. Multiple antimicrobial resistance of Escherichia coli and Salmonella ...

    African Journals Online (AJOL)

    Presumptive isolates were subjected to antimicrobial susceptibility testing using 13 panels of antibiotics for both E. coli and Salmonella spp. Results showed that the overall isolation rate of Salmonella spp. was 12 (11.4%), broiler chickens had higher isolation rate 9 (12.0%) of Salmonella than local chickens. However, the ...

  7. Salmonellae in avian wildlife in Norway from 1969 to 2000

    DEFF Research Database (Denmark)

    Refsum, T.; Handeland, K.; Baggesen, Dorte Lau

    2002-01-01

    Postmortem records of wild-living birds in Norway with laboratory-confirmed findings of salmonella infection were summarized for the period from 1969 to 2000. Salmonella spp. were isolated from 470 birds belonging to 26 species. The salmonella-positive birds included 441 small passerines, 15 gull...

  8. 78 FR 42451 - Animal Feeds Contaminated With Salmonella Microorganisms

    Science.gov (United States)

    2013-07-16

    .... FDA-2013-N-0253] Animal Feeds Contaminated With Salmonella Microorganisms AGENCY: Food and Drug... revoking an advisory opinion on animal feeds contaminated with Salmonella microorganisms. This action is... articulated in a final compliance policy guide (CPG) on Salmonella in food for animals. DATES: This rule is...

  9. Salmonella and Eggs: From Production to Plate

    Science.gov (United States)

    Whiley, Harriet; Ross, Kirstin

    2015-01-01

    Salmonella contamination of eggs and egg shells has been identified as a public health concern worldwide. A recent shift in consumer preferences has impacted on the egg industry, with a push for cage-free egg production methods. There has also been an increased desire from consumers for raw and unprocessed foods, potentially increasing the risk of salmonellosis. In response to these changes, this review explores the current literature regarding Salmonella contamination of eggs during the production processing through to food handling protocols. The contamination of eggs with Salmonella during the production process is a complex issue, influenced by many variables including flock size, flock age, stress, feed, vaccination, and cleaning routines. Currently there is no consensus regarding the impact of caged, barn and free range egg production has on Salmonella contamination of eggs. The literature regarding the management and control strategies post-collection, during storage, transport and food handling is also reviewed. Pasteurisation and irradiation were identified as the only certain methods for controlling Salmonella and are essential for the protection of high risk groups, whereas control of temperature and pH were identified as potential control methods to minimise the risk for foods containing raw eggs; however, further research is required to provide more detailed control protocols and education programs to reduce the risk of salmonellosis from egg consumption. PMID:25730295

  10. Salmonella capture using orbiting magnetic microbeads

    Science.gov (United States)

    Owen, Drew; Ballard, Matthew; Mills, Zachary; Hanasoge, Srinivas; Hesketh, Peter; Alexeev, Alexander

    2014-11-01

    Using three-dimensional simulations and experiments, we examine capture of salmonella from a complex fluid sample flowing through a microfluidic channel. Capture is performed using orbiting magnetic microbeads, which can easily be extracted from the system for analysis after salmonella capture. Numerical simulations are used to model the dynamics of the system, which consists of a microchannel filled with a viscous fluid, model salmonella, magnetic microbeads and a series of angled parallel ridges lining the top of the microchannel. Simulations provide a statistical measure of the ability of the system to capture target salmonella. Our modeling findings guide the design of a lab-on-a-chip experimental device to be used for the detection of salmonella from complex food samples, allowing for the detection of the bacteria at the food source and preventing the consumption of contaminated food. Such a device can be used as a generic platform for the detection of a variety of biomaterials from complex fluids. This work is supported by a grant from the United States Department of Agriculture.

  11. Salmonella and Eggs: From Production to Plate

    Directory of Open Access Journals (Sweden)

    Harriet Whiley

    2015-02-01

    Full Text Available Salmonella contamination of eggs and egg shells has been identified as a public health concern worldwide. A recent shift in consumer preferences has impacted on the egg industry, with a push for cage-free egg production methods. There has also been an increased desire from consumers for raw and unprocessed foods, potentially increasing the risk of salmonellosis. In response to these changes, this review explores the current literature regarding Salmonella contamination of eggs during the production processing through to food handling protocols. The contamination of eggs with Salmonella during the production process is a complex issue, influenced by many variables including flock size, flock age, stress, feed, vaccination, and cleaning routines. Currently there is no consensus regarding the impact of caged, barn and free range egg production has on Salmonella contamination of eggs. The literature regarding the management and control strategies post-collection, during storage, transport and food handling is also reviewed. Pasteurisation and irradiation were identified as the only certain methods for controlling Salmonella and are essential for the protection of high risk groups, whereas control of temperature and pH were identified as potential control methods to minimise the risk for foods containing raw eggs; however, further research is required to provide more detailed control protocols and education programs to reduce the risk of salmonellosis from egg consumption.

  12. Salmonella and eggs: from production to plate.

    Science.gov (United States)

    Whiley, Harriet; Ross, Kirstin

    2015-02-26

    Salmonella contamination of eggs and egg shells has been identified as a public health concern worldwide. A recent shift in consumer preferences has impacted on the egg industry, with a push for cage-free egg production methods. There has also been an increased desire from consumers for raw and unprocessed foods, potentially increasing the risk of salmonellosis. In response to these changes, this review explores the current literature regarding Salmonella contamination of eggs during the production processing through to food handling protocols. The contamination of eggs with Salmonella during the production process is a complex issue, influenced by many variables including flock size, flock age, stress, feed, vaccination, and cleaning routines. Currently there is no consensus regarding the impact of caged, barn and free range egg production has on Salmonella contamination of eggs. The literature regarding the management and control strategies post-collection, during storage, transport and food handling is also reviewed. Pasteurisation and irradiation were identified as the only certain methods for controlling Salmonella and are essential for the protection of high risk groups, whereas control of temperature and pH were identified as potential control methods to minimise the risk for foods containing raw eggs; however, further research is required to provide more detailed control protocols and education programs to reduce the risk of salmonellosis from egg consumption.

  13. Prevalence and Characteristics of Salmonella and Campylobacter in Retail Poultry Meat in Japan.

    Science.gov (United States)

    Furukawa, Ichiro; Ishihara, Tomoe; Teranishi, Hiroshi; Saito, Shioko; Yatsuyanagi, Jun; Wada, Eriko; Kumagai, Yuko; Takahashi, Shiho; Konno, Takayuki; Kashio, Hiroko; Kobayashi, Akihiko; Kato, Naoki; Hayashi, Ken-Ichi; Fukushima, Keisuke; Ishikawa, Kazuhiko; Horikawa, Kazumi; Oishi, Akira; Izumiya, Hidemasa; Ohnishi, Takahiro; Konishi, Yoshiko; Kuroki, Toshiro

    2017-05-24

    This study was performed to determine the prevalence, antimicrobial susceptibility, and genetic relatedness of Salmonella enterica subsp. enterica and Campylobacter spp. in poultry meat, and to analyze the association of genetic types of these bacteria with their geographical distribution and antimicrobial resistance profiles. Salmonella and Campylobacter isolates have been detected, respectively, in 54 and 71 samples out of 100 samples tested. Nine Salmonella serotypes were found, including S. enterica subsp. enterica serovar Infantis (33%), Schwarzengrund (12%), Manhattan (9%), and others. Campylobacter jejuni and C. coli were detected in 64 (64%) and 14 (14%) samples, respectively. S. enterica subsp. enterica isolates were very frequently resistant to tetracycline (78.3%) and streptomycin (68.3%). Many C. jejuni and C. coli isolates were resistant to sulfamethoxazole/trimethoprim (90.5%), nalidixic acid (47.3%), ampicillin (45.9%), and ciprofloxacin (40.5%). Cluster analysis was performed for the Salmonella isolates using pulsed-field gel electrophoresis (PFGE) data. For Campylobacter isolates, the cluster analysis was based on both PFGE and comparative genomic fingerprinting. The molecular typing results were compared with the information about antimicrobial resistance and geographical locations in which the poultry meat was produced. This analysis revealed that C. jejuni strains with a particular genotype and antimicrobial resistance profile are spreading in specific areas of Japan.

  14. Laboratory surveillance of Salmonella enterica from human clinical cases in Colombia 2005-2011.

    Science.gov (United States)

    Rodríguez, Edna Catering; Díaz-Guevara, Paula; Moreno, Jaime; Bautista, Adriana; Montaño, Lucy; Realpe, María Elena; Della Gaspera, Anabella; Wiesner, Magdalena

    Salmonella is an enteropathogen acquired through contaminated food or water. In Colombia, Salmonella spp. is included in the national surveillance of Acute Diarrhoeal Diseases and typhoid fever initiated in 1997. This report shows the phenotype and genotype results obtained from 2005 to 2011. A total of 4010 isolates of Salmonella enterica were analysed by serotyping with Kauffmann-White-LeMinor, antimicrobial resistance patterns, and pulse-field gel electrophoresis (PFGE). A total of 93 serovars were identified, of which, Typhimurium, Enteritidis, Typhi, Dublin, Panama, Derby, Braenderup, Saintpaul, and Uganda were prominent. The highest levels of resistance were found for tetracycline and nalidixic acid. Susceptibility was observed in 52.4% (2101/4010) of the isolates. Multi-resistance was recorded in 54.9% of Typhimurium isolates, with 81 different combinations. Using PFGE, 51.9% (2083/4010) isolates were analysed in 34 serovars, and 828 electrophoretic patterns were obtained. From these, 8 patterns were found in at least two Latin-American countries. The surveillance of Salmonella spp. provides information on the serovar distribution, antimicrobial resistance, and clonal distribution in Colombia, as well as information to treat this disease and control the spread of antimicrobial bacterial resistance. Copyright © 2016 Elsevier España, S.L.U. and Sociedad Española de Enfermedades Infecciosas y Microbiología Clínica. All rights reserved.

  15. Characterization of Nontyphoidal Salmonella Isolates from Asymptomatic Migrant Food Handlers in Peninsular Malaysia.

    Science.gov (United States)

    Woh, Pei Yee; Thong, Kwai Lin; Behnke, Jerzy Marian; Lewis, John Watkin; Zain, Siti Nursheena Mohd

    2017-08-01

    Asymptomatic Salmonella carriers who work as food handlers pose food safety and public health risks, particularly during food preparation, and this has serious implications for the disease burden in society. Therefore, we conducted a study to determine the number of Salmonella carriers in a migrant cohort in several food establishments in three major cities in Peninsular Malaysia. Sociodemographic data and stool samples were collected and analyzed using standard methods of detection and isolation. Antimicrobial susceptibility tests of the positive samples were also performed. A total of 317 migrant food handlers, originating from South and Southeast Asian countries, were recruited voluntarily. Nine (2.8%) stool samples were confirmed to be Salmonella positive. PCR serotyping and pulsed-field gel electrophoresis identified four serotypes as Typhimurium (n = 3), Corvallis (n = 2), Hadar (n = 1), Agona (n = 1) and two unknown serovars. Antimicrobial susceptibility tests revealed that all nine isolates were susceptible to amoxicillin-clavulanic acid, cefotaxime, ceftazidime, ceftriaxone, and gentamycin. However, seven isolates were found to be multidrug resistant to ampicillin, chloramphenicol, trimethoprim-sulfamethoxazole, sulfonamides, streptomycin, and tetracycline. This study highlights that carriers of nontyphoidal Salmonella exist among migrant food handlers, which poses a health risk to consumers through food contamination. Our results indicate a need for authorities to enhance food safety awareness in the migrant workers and to reevaluate current health screening methods to include preventive measure such as mandatory stool screening as part of the preemployment and routine health examinations.

  16. Comparison between digital PCR and real-time PCR in detection of Salmonella typhimurium in milk.

    Science.gov (United States)

    Wang, Meng; Yang, Junjie; Gai, Zhongtao; Huo, Shengnan; Zhu, Jianhua; Li, Jun; Wang, Ranran; Xing, Sheng; Shi, Guosheng; Shi, Feng; Zhang, Lei

    2018-02-02

    As a kind of zero-tolerance foodborne pathogens, Salmonella typhimurium poses a great threat to quality of food products and public health. Hence, rapid and efficient approaches to identify Salmonella typhimurium are urgently needed. Combined with PCR and fluorescence technique, real-time PCR (qPCR) and digital PCR (ddPCR) are regarded as suitable tools for detecting foodborne pathogens. To compare the effect between qPCR and ddPCR in detecting Salmonella typhimurium, a series of nucleic acid, pure strain culture and spiking milk samples were applied and the resistance to inhibitors referred in this article as well. Compared with qPCR, ddPCR exhibited more sensitive (10 -4 ng/μl or 10 2 cfu/ml) and less pre-culturing time (saving 2h). Moreover, ddPCR had stronger resistance to inhibitors than qPCR, yet absolute quantification hardly performed when target's concentration over 1ng/μl or 10 6 cfu/ml. This study provides an alternative strategy in detecting foodborne Salmonella typhimurium. Copyright © 2018 Elsevier B.V. All rights reserved.

  17. Evaluation of sanitizers for inactivating Salmonella on in-shell pecans and pecan nutmeats.

    Science.gov (United States)

    Beuchat, Larry R; Mann, David A; Alali, Walid Q

    2012-11-01

    Chlorine, organic acids, and water extracts of inedible pecan components were tested for effectiveness in killing Salmonella on pecans. In-shell pecans and nutmeats (U.S. Department of Agriculture medium pieces) were immersion inoculated with a mixture of five Salmonella serotypes, dried to 3.7% moisture, and stored at 4°C for 3 to 6 weeks. In-shell nuts were immersed in chlorinated water (200, 400, and 1,000 μg/ml), lactic acid (0.5, 1, and 2%), and levulinic acid (0.5, 1, and 2%) with and without 0.05% sodium dodecyl sulfate (SDS), and a mixed peroxyacid sanitizer (Tsunami 200, 40 μg/ml) for up to 20 min at 21°C. The rate of reduction of free chlorine in conditioning water decreased as the ratio of in-shell nuts/water was increased. The rate of reduction was more rapid when nuts were not precleaned before treatment. The initial population of Salmonella on in-shell nuts (5.9 to 6.3 log CFU/g) was reduced by 2.8 log CFU/g after treating with chlorinated water (1,000 μg/ml). Treatment with 2% lactic acid plus SDS or 2% levulinic acid plus SDS reduced the pathogen by 3.7 and 3.4 log CFU/g, respectively. Lactic and levulinic acids (2%) without SDS were less effective (3.3- and 2.1-log CFU/g reductions, respectively) than acids with SDS. Treatment with Tsunami 200 resulted in a 2.4-log CFU/g reduction. In-shell nuts and nutmeats were immersed in water extracts of ground pecan shucks (hulls), shells, a mixture of shells and pith, and pith. The general order of lethality of extracts to Salmonella was shuck pecans before conditioning in chlorinated water and the need for sanitizers with increased effectiveness in killing Salmonella on pecans.

  18. Association with MDCK epithelial cells by Salmonella typhimurium is reduced during utilization of carbohydrates.

    OpenAIRE

    Schiemann, D A

    1995-01-01

    Association of Salmonella typhimurium with MDCK epithelial cells in monolayers, represented primarily by intracellular bacteria after 30 min of contact, with centrifugation followed by vigorous washing, was measured during aerobic and anaerobic growth of the bacteria in brain heart infusion broth. Cell association was greatest during a short period in the late log phase of growth under aerobic conditions. At this time, the pH of the growth medium was changing from acid to alkaline and glucose...

  19. Inhibitors of amino acids biosynthesis as antifungal agents.

    Science.gov (United States)

    Jastrzębowska, Kamila; Gabriel, Iwona

    2015-02-01

    Fungal microorganisms, including the human pathogenic yeast and filamentous fungi, are able to synthesize all proteinogenic amino acids, including nine that are essential for humans. A number of enzymes catalyzing particular steps of human-essential amino acid biosynthesis are fungi specific. Numerous studies have shown that auxotrophic mutants of human pathogenic fungi impaired in biosynthesis of particular amino acids exhibit growth defect or at least reduced virulence under in vivo conditions. Several chemical compounds inhibiting activity of one of these enzymes exhibit good antifungal in vitro activity in minimal growth media, which is not always confirmed under in vivo conditions. This article provides a comprehensive overview of the present knowledge on pathways of amino acids biosynthesis in fungi, with a special emphasis put on enzymes catalyzing particular steps of these pathways as potential targets for antifungal chemotherapy.

  20. Test results of Salmonella serotyping in the Member States of the European Union. (Collaborative study III amongst the National Reference Laboratories for Salmonella)

    NARCIS (Netherlands)

    Voogt N; Maas HME; Leeuwen WJ van; Henken AM; MGB

    1998-01-01

    Het Communautair Referentie Laboratorium (CRL) voor Salmonella heeft een derde ringonderzoek voor de serotypering van Salmonella georganiseerd. Alle Nationale Referentie Laboratoria (NRLs) voor Salmonella van de Europese Unie deden aan het onderzoek mee. Het belangrijkste doel was het

  1. Molecular characterization of Salmonella Paratyphi B dT+ and Salmonella Heidelberg from poultry and retail chicken meat in Colombia by pulsed-field gel electrophoresis

    Science.gov (United States)

    Salmonella Paratyphi B dT+ variant (also termed Salmonella Java) and Salmonella Heidelberg are human pathogens frequently isolated from poultry. As a step towards implementing the Colombian Integrated Program for Antimicrobial Resistant Surveillance (COIPARS), this study characterized molecular patt...

  2. Bacteriological detection of Salmonella in the presence of competitive micro-organisms (A collaborative study amongst the National Reference Laboratories for Salmonella)

    NARCIS (Netherlands)

    Voogt N; Veld PH in ' t; Nagelkerke N; Henken AM; MGB

    1997-01-01

    Het Communautair Referentie Laboratorium voor Salmonella heeft een tweede bacteriologisch ringonderzoek georganiseerd met deelname van de Nationale Referentie Laboratoria voor Salmonella. Het belangrijkste doel van dit onderzoek was verschillen tussen de NRLs in de resultaten van Salmonella

  3. Comparing validation of four ELISAsystems for detection of Salmonella Derby- and Salmonella Infantis-infected pigs

    OpenAIRE

    Rösler, Uwe; Szabo, Istvan; Matthies, Claudia; Albrecht, Kerstin; Leffler, Kerstin; Scherer, Kathrin; Nöckler, Karsten; Lehmann, Jörg; Methner, Ulrich; Hensel, Andreas

    2018-01-01

    The objective of this study was the comparative evaluation of four indirect Salmonella ELISA tests at study time approved in Germany to detect Salmonella infection in pigs. Three tests are based on a LPS-antigen mix and directed against specific IgG antibodies. The fourth test is based on a purified S. Typhimurium whole-cell lysate antigen and discriminates between Salmonella-specific IgM-, IgA-, and IgG- antibodies. In a longitudinal study, two groups of six weeks old hybrid piglets were ...

  4. Oral immunisation of laying hens with the live vaccine strains of TAD Salmonella vac E and TAD Salmonella vac T reduces internal egg contamination with Salmonella Enteritidis.

    Science.gov (United States)

    Gantois, Inne; Ducatelle, Richard; Timbermont, Leen; Boyen, Filip; Bohez, Lotte; Haesebrouck, Freddy; Pasmans, Frank; van Immerseel, Filip

    2006-09-11

    Eggs are a major source of human infections with Salmonella. Therefore controlling egg contamination in laying hen flocks is one of the main targets for control programmes. A study was carried out to assess the effect of oral vaccination with TAD Salmonella vac E, TAD Salmonella vac T and with both vaccines TAD Salmonella vac E and TAD Salmonella vac T, on colonization of the reproductive tract and internal egg contamination of laying hens with Salmonella Enteritidis. Three groups of 30 laying hens were vaccinated at 1 day, 6 weeks and 16 weeks of age with either one of the vaccine strains, or a combination of both vaccine strains, while a fourth group was left unvaccinated. At 24 weeks of age, the birds were intravenously challenged with 0.5 ml containing 5 x 10(7)cfu Salmonella Enteritidis PT4 S1400/94. The number of oviducts from which Salmonella was isolated, was significantly lower in the vaccinated than in the non-vaccinated hens at 3 weeks post-challenge. Significantly less egg contents were Salmonella positive in the birds vaccinated with TAD Salmonella vac E or TAD Salmonella vac T (12/105 batches of eggs in both groups) than in the unvaccinated birds (28/105 batches of eggs). Internal egg contamination in the hens vaccinated with both TAD Salmonella vac E and TAD Salmonella vac T was even more reduced, as over the whole experiment, only one batch of eggs was positive. In conclusion, these data indicate that vaccination of laying hens with these live vaccines could be considered as a valuable tool in controlling internal egg contamination.

  5. Production of the Plant Hormone Auxin by Salmonella and Its Role in the Interactions with Plants and Animals.

    Science.gov (United States)

    Cox, Clayton E; Brandl, Maria T; de Moraes, Marcos H; Gunasekera, Sarath; Teplitski, Max

    2017-01-01

    The ability of human enteric pathogens to colonize plants and use them as alternate hosts is now well established. Salmonella , similarly to phytobacteria, appears to be capable of producing the plant hormone auxin via an indole-3-pyruvate decarboxylase (IpdC), a key enzyme of the IPyA pathway. A deletion of the Salmonella ipdC significantly reduced auxin synthesis in laboratory culture. The Salmonella ipdC gene was expressed on root surfaces of Medicago truncatula . M. truncatula auxin-responsive GH3::GUS reporter was activated by the wild type Salmonella , and not but the ipdC mutant, implying that the bacterially produced IAA (Indole Acetic Acid) was detected by the seedlings. Seedling infections with the wild type Salmonella caused an increase in secondary root formation, which was not observed in the ipdC mutant. The wild type Salmonella cells were detected as aggregates at the sites of lateral root emergence, whereas the ipdC mutant cells were evenly distributed in the rhizosphere. However, both strains appeared to colonize seedlings well in growth pouch experiments. The ipdC mutant was also less virulent in a murine model of infection. When mice were infected by oral gavage, the ipdC mutant was as proficient as the wild type strain in colonization of the intestine, but it was defective in the ability to cross the intestinal barrier. Fewer cells of the ipdC mutant, compared with the wild type strain, were detected in Peyer's patches, spleen and in the liver. Orthologs of ipdC are found in all Salmonella genomes and are distributed among many animal pathogens and plant-associated bacteria of the Enterobacteriaceae , suggesting a broad ecological role of the IpdC-catalyzed pathway.

  6. International collaborative study on the occurrence of plasmid-mediated quinolone resistance in Salmonella enterica and Escherichia coli isolated from animals, humans, food and the environment in 13 European countries

    DEFF Research Database (Denmark)

    Veldman, Kees; Cavaco, Lina; Mevius, Dik

    2011-01-01

    OBJECTIVES: This study was initiated to collect retrospective information on the occurrence of plasmid-mediated quinolone resistance (PMQR) in Salmonella enterica and Escherichia coli isolates in Europe and to identify the responsible genes. METHODS: Databases of national reference laboratories...... containing MIC values for Salmonella and E. coli isolated between 1994 and 2009 in animals, humans, food and the environment from 13 European countries were screened for isolates exhibiting a defined quinolone resistance phenotype, i.e. reduced susceptibility to fluoroquinolones and nalidixic acid. PCR...... isolate. No qnrC or qepA genes were detected in either Salmonella or E. coli. CONCLUSIONS: This study shows the occurrence and dissemination of PMQR genes in Salmonella and E. coli in Europe with a defined quinolone resistance phenotype. We also report the first detection of qnrD in Salmonella collected...

  7. Salmonella epidemiology: A whirlwind of change.

    Science.gov (United States)

    Besser, John M

    2018-05-01

    The field of infectious disease epidemiology for Salmonella and other enteric pathogens is undergoing some of the most profound changes since the time of Kauffman and White. Rapid advances in "big data" technologies such as genomics and metagenomics are making it possible to monitor and control salmonellosis in new and exciting ways. Epidemiological methods are becoming increasingly robust through the routine use of standardized hypothesis-generating questionnaires, iterative open-ended interviewing, informational trace-backs and new modeling techniques for describing the attribution of disease to food sources. In addition, Salmonella epidemiology is facing important challenges and new opportunities due to the rapid adoption of culture independent diagnostic test panels by clinical laboratories. Where is this unprecedented wave of change taking us? This chapter will examine emerging trends in Salmonella epidemiology, and take a peek into the not-so-distant future. Published by Elsevier Ltd.

  8. Assessment of Salmonella survival in dry-cured Italian salami.

    Science.gov (United States)

    Bonardi, S; Bruini, I; Bolzoni, L; Cozzolino, P; Pierantoni, M; Brindani, F; Bellotti, P; Renzi, M; Pongolini, S

    2017-12-04

    The inactivation of Salmonella during curing of Italian traditional pork salami was investigated. A total of 150 batches of ground raw meat (GRM) used for salami manufacturing by four producers were tested for Salmonella by real-time PCR followed by ISO 6579 cultural confirmation and MPN enumeration. Salami produced with Salmonella positive GRMs were re-tested at the end of their curing period. Aw, pH and NaCl content were also measured. Detection of Salmonella was performed testing both 25 and 50g of the samples. By Real-Time PCR 37% of the GRMs resulted positive, but cultural detection of Salmonella was obtained in 14% of the samples only. Salmonella enumeration ranged from 31 MPN/g to Salmonella in 100% of all positive samples, vs. 62% of ISO-25g. Salami made of the contaminated GRMs were 29% Salmonella-positive, as most batches of salami produced with Salmonella-positive GRMs resulted negative after regular curing (20-48days). Overall, 13% of salami produced with Salmonella-contaminated GRMs were positive. They belonged to six batches, which turned out negative after prolonged curing ranging between 49 and 86days. Salmonella enumeration in salami ranged from 8.7 MPN/g to Salmonella in cured salami (p value: >0.05). The most common Salmonella serovars in GRMs were Derby (52%), Typhimurium monophasic variant 4, (Barbuti et al., 1993), 12:i:- (19%) and Stanley (10%). Salmonella Derby (56%), London, Branderup, Panama (13%, respectively) and Goldcoast (6%) were most frequent in cured salami. The study showed negative correlation between real-time CT values and cultural confirmation of Salmonella, as well as the importance of sample size for Salmonella detection. Among considered factors with possible effect on the occurrence of Salmonella in salami, statistical analysis revealed a role for aw in salami and for Salmonella load in GRMs, while pH and NaCl content did not significantly affect the probability of finding Salmonella in dry-cured salami in the context of

  9. Inactivation of Salmonellae in Frozen Catfish by Gamma Irradiation

    International Nuclear Information System (INIS)

    Nouchpramoon, Kovit; Amsiri, Jarurat

    2003-06-01

    The effect of gamma irradiation on salmonellae viability in frozen catfish was investigated using fresh cut of catfish artificially contaminated with stationary phase cells of salmonellae, frozen at-18 οC and irradiated with does ranging from 0.0 to 2.4 kGy. The D 10 values for ten serovars of salmonellae ranged from 0.47 to 0.77 kGy. Salmonella Enteritidis was the most resistant serovars found in frozen catfish. Dosage at 2.5 kGy would be sufficient to kill 10 3 . 2 Salmonella Enteritidis that may occasionally present in frozen catfish

  10. Septic arthritis of the ankle due to Salmonella enteritidis.

    LENUS (Irish Health Repository)

    Dineen, Patrick F

    2011-06-01

    Salmonella septic arthritis in healthy, immunocompetent patients is extremely rare. We present the case of a 70-year-old man who presented with a one-day history of painful swelling of his ankle from which was aspirated pus which subsequently grew Salmonella enteritidis. There was no history of trauma or symptoms consistent with Salmonella enterocolitis. Our patient recovered fully after two weeks on intravenous ceftriaxone and six weeks on oral ciprofloxacin. Salmonella is a notifiable disease in the European Union and the United States of America, and is associated with outbreaks as a result of food contamination. The nature of Salmonella arthritis and its appropriate management are outlined.

  11. Prevalence of Salmonella spp. in reptiles

    OpenAIRE

    加藤, 行男; 村上, 賢

    2007-01-01

    A total of 291 fecal samples from 252 wild reptiles and 39 pet reptiles were examined for the prevalence of Salmonella spp. in Japan. Salmonella spp. were isolated from 29 (11.5%) of 252 wild reptiles and 22 (55.6%) of 39 pet reptiles. The isolates were identified into subspecies I to IV. The majority of isolates (43.6%) belonged to subspecies I and these isolates could be identified into 9 serovars. The serovars isolated were found to be S. Newport, S. Litchifield and S. Thompson which cause...

  12. Salmonella-infektion kompliceret med akut nyreinsufficiens

    DEFF Research Database (Denmark)

    Thøgersen, Thøger; Jensen, Jørgen Erik; Jespersen, Bente

    2003-01-01

    Acute renal failure is a known complication to Salmonella gastroenteritis, and patients with chronic renal failure or impaired host defence are at increased risk. In the two presented cases there had been a few days of gastroenteritis before the hospitalisation, but the only symptoms...... at the admission were fatigue and dyspnoea. In both cases severe uraemia had developed and the patients and their physicians did not expect the episode of gastroenteritis to be the only etiology of acute renal failure. Both patients had normal renal histology and Salmonella was grown in their faeces. Subsequently...

  13. Salmonella in Brazilian and imported pet reptiles

    OpenAIRE

    Sá,Isabel Valéria Abalem de; Solari,Claude André

    2001-01-01

    The presence of salmonellae in fecal samples or cloacal swabs of 97 pet reptiles (15 snakes, 24 lizards and 58 chelonians) was investigated. Thirty seven animals had national origin and 60 were imported. Salmonella spp was detected in 39.1% of the reptiles, being 62.5% in lizards, 53.3% in snakes and 25.8% in chelonians. Strains belonged to subspecies I (44.7%), II (10.5%), IIIa (5.2%), IIIb (21.0%) and IV (18.5%) of the enterica species, with predominance (55.3%) of subspecies usually found ...

  14. Antimicrobial resistance in Salmonella spp. recovered from patients admitted to six different hospitals in Tehran, Iran from 2007 to 2008

    DEFF Research Database (Denmark)

    Tajbakhsh, Mercedeh; Hendriksen, Rene S.; Nochi, Zahra

    2012-01-01

    were screened for the presence of Salmonella, serotyped, tested for antimicrobial susceptibility using disk diffusion and examined for the presence of relevant resistance genes and integrons by PCR. A total of 1,120 patients were screened for the presence of Salmonella. Out of 71 Salmonella isolates...... recovered, the following serovars were identified: 17 Typhi, 14 Paratyphi C, 13 Enteritidis, 11 Paratyphi B, 10 Paratyphi A and six Infantis. Most resistance was observed towards sulfamethoxazole (30%), tetracyclines (25%), nalidixic acid (22%), spectinomycin (17%), trimethoprim (15%), ampicillin (14......%) and kanamycin (14%). The tetracycline resistance genes tet(A), tet(B), and tet(G) were found in 28%, 14% and 6% of the tetracycline resistant isolates, respectively. The genes aadA, aadB, strA, strB and aphA1-Iab were present in 83%, 55%, 34%, 1% and 17% of the aminoglycoside resistant isolates, respectively...

  15. Rapid radiometric method for detection of Salmonella in foods

    International Nuclear Information System (INIS)

    Stewart, B.J.; Eyles, M.J.; Murrell, W.G.

    1980-01-01

    A radiometric method for the detection of Salmonella in foods has been developed which is based on Salmonella poly H agglutinating serum preventing Salmonella from producing 14CO2 from [14C] dulcitol. The method will detect the presence or absence of Salmonella in a product within 30 h compared to 4 to 5 days by routine culture methods. The method has been evaluated against a routine culture method using 58 samples of food. The overall agreement was 91%. Five samples negative for Salmonella by the routine method were positive by the radiometric method. These may have been false positives. However, the routine method may have failed to detect Salmonella due to the presence of large numbers of lactose-fermenting bacteria which hindered isolation of Salmonella colonies on the selective agar plates

  16. Antimicrobial resistance of fecal Salmonella spp. isolated from all phases of pig production in 20 herds in Alberta and Saskatchewan

    OpenAIRE

    Rosengren, Leigh B.; Waldner, Cheryl L.; Reid‐Smith, Richard J.; Checkley, Sylvia L.; McFall, Margaret E.; Rajíc, Andrijana

    2008-01-01

    Salmonella spp. (n = 468), isolated from the feces of sows, nursery, and grow‐finish pigs in 20 farrow‐to‐finish herds in Alberta and Saskatchewan, were tested for susceptibility to 16 antimicrobials. No resistance was identified to amikacin, amoxicillin‐clavulanic acid, ceftiofur, ceftriaxone, ciprofloxacin or nalidixic acid, and less than 1% of the isolates were resistant to cefoxitin and gentamicin. Isolates were most commonly resistant to tetracycline (35%) and sulfamethoxazole (27%). Ove...

  17. Structural characterization of the Salmonella typhimurium LT2 umu operon

    International Nuclear Information System (INIS)

    Thomas, S.M.; Crowne, H.M.; Pidsley, S.C.; Sedgwick, S.G.

    1990-01-01

    The umuDC operon of Escherichia coli encodes functions required for mutagenesis induced by radiation and a wide variety of chemicals. The closely related organism Salmonella typhimurium is markedly less mutable than E. coli, but a umu homolog has recently been identified and cloned from the LT2 subline. In this study the nucleotide sequence and structure of the S. typhimurium LT2 umu operon have been determined and its gene products have been identified so that the molecular basis of umu activity might be understood more fully. S. typhimurium LT2 umu consists of a smaller 417-base-pair (bp) umuD gene ending 2 bp upstream of a larger 1,266-bp umuC gene. The only apparent structural difference between the two operons is the lack of gene overlap. An SOS box identical to that found in E. coli is present in the promoter region upstream of umuD. The calculated molecular masses of the umuD and umuC gene products were 15.3 and 47.8 kilodaltons, respectively, which agree with figures determined by transpositional disruption and maxicell analysis. The S. typhimurium and E. coli umuD sequences were 68% homologous and encoded products with 71% amino acid identity; the umuC sequences were 71% homologous and encoded products with 83% amino acid identity. Furthermore, the potential UmuD cleavage site and associated catalytic sites could be identified. Thus the very different mutagenic responses of S. typhimurium LT2 and E. coli cannot be accounted for by gross differences in operon structure or gene products. Rather, the ability of the cloned S. typhimurium umuD gene to give stronger complementation of E. coli umuD77 mutants in the absence of a functional umuC gene suggests that Salmonella UmuC protein normally constrains UmuD protein activity

  18. Tissue dyslipidemia in salmonella-infected rats treated with amoxillin and pefloxacin

    Directory of Open Access Journals (Sweden)

    Rotimi Solomon O

    2012-11-01

    Full Text Available Abstract Background This study investigated the effects of salmonella infection and its chemotherapy on lipid metabolism in tissues of rats infected orally with Salmonella typhimurium and treated intraperitoneally with pefloxacin and amoxillin. Methods Animals were infected with Salmonella enterica serovar Typhimurium strain TA 98. After salmonellosis was confirmed, they were divided into 7 groups of 5 animals each. While one group served as infected control group, three groups were treated with amoxillin (7.14 mg/kg body weight, 8 hourly and the remaining three groups with pefloxacin (5.71mg/kg body weight, 12 hourly for 5 and 10 days respectively. Uninfected control animals received 0.1ml of vehicle. Rats were sacrificed 24h after 5 and 10 days of antibiotic treatment and 5 days after discontinuation of antibiotic treatment. Their corresponding controls were also sacrificed at the same time point. Blood and tissue lipids were then evaluated. Results Salmonella infection resulted in dyslipidemia characterised by increased concentrations of free fatty acids (FFA in plasma and erythrocyte, as well as enhanced cholesterogenesis, hypertriglyceridemia and phospholipidosis in plasma, low density lipoprotein-very low density lipoprotein (LDL-VLDL, erythrocytes, erythrocyte ghost and the organs. The antibiotics reversed the dyslipidemia but not totally. A significant correlation was observed between fecal bacterial load and plasma cholesterol (r=0.456, p Conclusion The findings of this study suggest that salmonella infection in rats and its therapy with pefloxacin and amoxillin perturb lipid metabolism and this perturbation is characterised by cholesterogenesis.

  19. Frequency, serotyping and antimicrobial resistance pattern of Salmonella from feces and lymph nodes of pigs

    Directory of Open Access Journals (Sweden)

    João B.P. Guerra Filho

    Full Text Available ABSTRACT: Salmonellosis is a foodborne disease caused by bacteria of the genus Salmonella, being pigs and pork-products potentially important for its occurrence. In recent decades, some serovars of Salmonella have shown increase of resistance to conventional antimicrobials used in human and animal therapy, with serious risks for public health. The aim of this study was to evaluate feces (n=50, mediastinal (n=50, mesenteric (n=50 and mandibular (n=50 lymph nodes obtained from slaughter houses for Salmonella spp. Positive samples were serotyped and subjected to an in vitro antimicrobial susceptibility test, including the extended-spectrum beta-lactamase (ESBL production. Salmonella species were identified in 10% (20/200 of total samples. From these, 20% (10/50 were identified in the submandibular lymph nodes, 18% (9/50 in the mesenteric lymph nodes, 2% (1/50 in feces and 0% (0/50 in the mediastinal lymph nodes. The serotypes found were Salonella Typhimurium (55%, S. enterica subsp. enterica 4,5,12: i: - (35%, S. Brandenburg and S. Derby with 5% (5% each. All strains showed resistance to at least one antimicrobial; 90% were resistant to four or more antimicrobials, and 15% were multidrug-resistant. Resistance to ciprofloxacin, tetracycline and nalidixic acid was particularly prevalent amongst the tested serovars. Here, we highlighted the impact of pigs in the epidemiological chain of salmonellosis in domestic animals and humans, as well as the high antimicrobial resistance rates of Salmonella strains, reinforcing the necessity for responsible use of antimicrobials for animals as an emergent One Health issue, and to keep these drugs for human therapy approaches.

  20. Effects of dietary alfalfa inclusion on Salmonella typhimurium populations in growing layer chicks.

    Science.gov (United States)

    Escarcha, Jacquelyn F; Callaway, Todd R; Byrd, J Allen; Miller, Dan N; Edrington, Tom S; Anderson, Robin C; Nisbet, David J

    2012-10-01

    Reducing Salmonella in poultry has been a paramount goal of the poultry industry in order to improve food safety. Inclusion of high-fiber fermentable feedstuffs in chicken diets has been shown to reduce the incidence of Salmonella colonization in laying hens, but no work has been performed in growing birds. Therefore, the present study was designed to quantify differences in artificially inoculated cecal Salmonella Typhimurium populations in growing layer chicks (n = 60 in each of two replications) fed 0%, 25%, and 50% of their diet (w/w) replaced with alfalfa meal from day (d) 7 to d14 after hatch. Alfalfa supplementation reduced cecal populations of Salmonella by 0.95 and 1.25 log10 colony-forming unit per gram in the 25% and 50% alfalfa groups compared to controls. Alfalfa feeding reduced (p < 0.05) the number of cecal- and crop-positive birds compared to controls. Increasing levels of alfalfa increased (p < 0.05) total volatile fatty acids (VFA) and the proportion of acetate in the cecum. Surprisingly, alfalfa inclusion did not negatively impact average daily gain (ADG) in birds over the 7-d feeding period. Alfalfa inclusion at 50% of the diet increased (p < 0.05) the number of bacterial genera detected in the cecum compared to controls, and also altered proportions of the microbial population by reducing Ruminococcus and increasing Clostridia populations. Results support the idea that providing a fermentable substrate can increase gastrointestinal VFA production and bacterial diversity which in turn can reduce colonization by Salmonella via natural competitive barriers. However, further studies are obviously needed to more fully understand the impact of changes made in diet or management procedures on poultry production.

  1. Radiation sensitivity of Salmonella isolates relative to resistance to ampicillin, chloramphenicol or gentamicin

    Science.gov (United States)

    Niemira, Brendan A.; Lonczynski, Kelly A.; Sommers, Christopher H.

    2006-09-01

    Antibiotic resistance of inoculated bacteria is a commonly used selective marker. Bacteria resistant to the antibiotic nalidixic acid have been shown to have an increased sensitivity to irradiation. The purpose of this research was to screen a collection of Salmonella isolates for antibiotic resistance and determine the association, if any, of antibiotic resistance with radiation sensitivity. Twenty-four clinical isolates of Salmonella were screened for native resistance to multiple concentrations of ampicillin (Amp), chloramphenicol (Chl), or gentamicin (Gm). Test concentrations were chosen based on established clinical minimum inhibitory concentration (MIC) levels, and isolates were classified as either sensitive or resistant based on their ability to grow at or above the MIC. Salmonella cultures were grown overnight at (37 °C) in antibiotic-amended tryptic soy broth (TSB). Native resistance to Gm was observed with each of the 24 isolates (100%). Eight isolates (33%) were shown to be resistant to Amp, while seven isolates (29%) were shown to be resistant to Chl. In separate experiments, Salmonella cultures were grown overnight (37 °C) in TSB, centrifuged, and the cell pellets were re-suspended in phosphate buffer. The samples were then gamma irradiated at doses up to 1.0 kGy. The D10 values (the ionizing radiation dose required to reduce the viable number of microorganisms by 90%) were determined for the 24 isolates and they ranged from 0.181 to 0.359 kGy. No correlation was found between the D10 value of the isolate and its sensitivity or resistance to each of the three antibiotics. Resistance to Amp or Chl is suggested as appropriate resistance marker for Salmonella test strains to be used in studies of irradiation.

  2. Radiation sensitivity of Salmonella isolates relative to resistance to ampicillin, chloramphenicol or gentamicin

    International Nuclear Information System (INIS)

    Niemira, Brendan A.; Lonczynski, Kelly A.; Sommers, Christopher H.

    2006-01-01

    Antibiotic resistance of inoculated bacteria is a commonly used selective marker. Bacteria resistant to the antibiotic nalidixic acid have been shown to have an increased sensitivity to irradiation. The purpose of this research was to screen a collection of Salmonella isolates for antibiotic resistance and determine the association, if any, of antibiotic resistance with radiation sensitivity. Twenty-four clinical isolates of Salmonella were screened for native resistance to multiple concentrations of ampicillin (Amp), chloramphenicol (Chl), or gentamicin (Gm). Test concentrations were chosen based on established clinical minimum inhibitory concentration (MIC) levels, and isolates were classified as either sensitive or resistant based on their ability to grow at or above the MIC. Salmonella cultures were grown overnight at (37 o C) in antibiotic-amended tryptic soy broth (TSB). Native resistance to Gm was observed with each of the 24 isolates (100%). Eight isolates (33%) were shown to be resistant to Amp, while seven isolates (29%) were shown to be resistant to Chl. In separate experiments, Salmonella cultures were grown overnight (37 o C) in TSB, centrifuged, and the cell pellets were re-suspended in phosphate buffer. The samples were then gamma irradiated at doses up to 1.0 kGy. The D 10 values (the ionizing radiation dose required to reduce the viable number of microorganisms by 90%) were determined for the 24 isolates and they ranged from 0.181 to 0.359 kGy. No correlation was found between the D 10 value of the isolate and its sensitivity or resistance to each of the three antibiotics. Resistance to Amp or Chl is suggested as appropriate resistance marker for Salmonella test strains to be used in studies of irradiation

  3. Effects of gamma radiations on some aspects of the biology of salmonella

    International Nuclear Information System (INIS)

    Ben Miloud, Najla

    2007-01-01

    This work aimed at the study of the effect of gamma radiation on certain aspects of the biology of Salmonella, few works joined this type and gamma radiations. The lethal effect of ionizing radiations was associated at other bacterial types, to an oxidative stress due to the presence of reactive spices of oxygen and leading to deteriorations of membrane cells, proteins and nucleic acids.Thus, we proceeded to an analysis of the viability of four Salmonella serovars subject to different radiation doses going from 0.5 to 2 KGy. The results showed a viability reduction dose dependent with a differential behavior, statistically significant. In order to detect possible radio induced changes at the restriction site of the enzymes XbaI and BlnI usually used for the typing of Salmonella, we carried out a DNA restriction profile analyse of the four serovars by pulsed filed gel electrophoresis. The results showed that no change appeared on the level of these restriction sites for the used enzymes following an irradiation of 2KGy. The study of the sensitivity of Salmonella to antibiotics after a gamma radiation showed that gamma radiation has increased the sensitivity of Salmonella isolates to porin associated antibiotics. Statistical analyses showed that the effect of different irradiation dose treatment on the antibiotic sensitivity is increasingly significant. The irradiation didn't induce modifications of the sensitivity to other antibiotics, probably because of their nature, of their penetration mode inside the cell or their action way. To tray to explain the differential behavior of different serovars to irradiation. We analyzed by Quantitative real time PCR (RT- PCR), the expression level of the ARNm of the genes KATN (catalase non-hemique), DNAK (protein of thermal shock), RNA polymerase as well as of the 16S rRNA. The results showed either a repression or an induction of certain genes under the effect of an irradiation of 2 KGy. (Author)

  4. Report on the seventh workshop organised by CRL-Salmonella. Ploufragan (France), 28 May 2002

    NARCIS (Netherlands)

    Korver H; Raamsdonk EC van; Henken AM; MGB

    2002-01-01

    At 28 May 2002 a workshop was organised by the Community Reference Laboratory for Salmonella (CRL-Salmonella) in Ploufragan, France. All National Reference Laboratories for Salmonella (NRLs-Salmonella) of the EU Member States, with the exception of the Greek and the Northern-Ireland NRLs-Salmonella,

  5. Arginine and vitamin E improve the immune response after a Salmonella challenge in broiler chicks.

    Science.gov (United States)

    Liu, X; Byrd, J A; Farnell, M; Ruiz-Feria, C A

    2014-04-01

    Two experiments were conducted to evaluate the effects of Arg, vitamin E (VE), and mannanoligosaccharide (MOS) on the immune response and clearance of Salmonella in broiler chickens. In each experiment, 1-d-old chicks (n = 160) were randomly distributed into 4 groups: antibiotic-free diet (negative control, CTL-), antibiotic-supplemented diet (positive control, CTL+), antibiotic free-diet plus Arg and VE (AVE), or antibiotic-free diet plus Arg, VE, and MOS (AVM). Birds were orally challenged with 10(6) cfu of a novobiocyn and nalidixic acid-resistant Salmonella enterica serovar Typhimurium strain at d 7 (experiment 1) or at d 3 (experiment 2). Heterophil- (HOB) and monocyte- (MOB) oxidative burst and lymphocyte proliferation (LPR), antibody titers, and Salmonella content in the ceca were measured at several intervals postinfection (PI). In experiment 1, both AVM and AVE decreased HOB compared with the controls 5 and 9 d PI, but increased LPR 9 d PI. In the same experiment, birds fed the AVE diet had higher MOB than birds fed CTL+ or the AVM diet at 7 d PI, whereas 9 d PI birds fed the AVM diet had the highest MOB. In experiment 2, birds fed the AVE diet had higher MOB, HOB, and LPR than birds in the other treatments 7 and 14 d PI, except at 7 d PI, when MOB was not different among treatments. Birds fed the AVM diet had the highest IgA antibody titer, and a higher IgM antibody titer than the CTL+ birds. In experiment 1, Salmonella Typhimurium content in the ceca was lower in birds fed the AVM diet compared with birds fed the CTL- diet 3 d PI, but later on (10 and 17 d PI), and in experiment 2 (7, 14, and 21 d PI), Salmonella Typhimurium concentrations were not different among treatments. Thus, Arg and VE improved immune response after a Salmonella Typhimurium challenge in young chicks, and although they did not reduce Salmonella Typhimurium concentrations in the ceca, they may improve bacterial resistance against other pathogens in commercial growing conditions.

  6. Antimicrobial Resistance Percentages of Salmonella and Shigella in Seafood Imported to Jordan: Higher Percentages and More Diverse Profiles in Shigella.

    Science.gov (United States)

    Obaidat, Mohammad M; Bani Salman, Alaa E

    2017-03-01

    This study determined the prevalence and antimicrobial resistance of human-specific ( Shigella spp.) and zoonotic ( Salmonella enterica ) foodborne pathogens in internationally traded seafood. Sixty-four Salmonella and 61 Shigella isolates were obtained from 330 imported fresh fish samples from Egypt, Yemen, and India. The pathogens were isolated on selective media, confirmed by PCR, and tested for antimicrobial resistance. Approximately 79 and 98% of the Salmonella and Shigella isolates, respectively, exhibited resistance to at least one antimicrobial, and 8 and 49% exhibited multidrug resistance (resistance to three or more antimicrobial classes). Generally, Salmonella exhibited high resistance to amoxicillin-clavulanic acid, cephalothin, streptomycin, and ampicillin; very low resistance to kanamycin, tetracycline, gentamicin, chloramphenicol, nalidixic acid, sulfamethoxazole-trimethoprim, and ciprofloxacin; and no resistance to ceftriaxone. Meanwhile, Shigella spp. exhibited high resistance to tetracycline, amoxicillin-clavulanic acid, cephalothin, streptomycin, and ampicillin; low resistance to kanamycin, nalidixic acid, sulfamethoxazole-trimethoprim, and ceftriaxone; and very low resistance to gentamicin and ciprofloxacin. Salmonella isolates exhibited 14 resistance profiles, Shigella isolates 42. This study is novel in showing that a human-specific pathogen has higher antimicrobial resistance percentages and more diverse profiles than a zoonotic pathogen. Thus, the impact of antimicrobial use in humans is as significant as, if not more significant than, it is in animals in spreading antibiotic resistance through food. This study also demonstrates that locally derived antimicrobial resistance can spread and pose a public health risk worldwide through seafood trade and that high resistance would make a possible outbreak difficult to control. So, capacity building and monitoring harvest water areas are encouraged in fish producing countries.

  7. Swiss Army Pathogen: The Salmonella Entry Toolkit

    Directory of Open Access Journals (Sweden)

    Peter J. Hume

    2017-08-01

    Full Text Available Salmonella causes disease in humans and animals ranging from mild self-limiting gastroenteritis to potentially life-threatening typhoid fever. Salmonellosis remains a considerable cause of morbidity and mortality globally, and hence imposes a huge socio-economic burden worldwide. A key property of all pathogenic Salmonella strains is the ability to invade non-phagocytic host cells. The major determinant of this invasiveness is a Type 3 Secretion System (T3SS, a molecular syringe that injects virulence effector proteins directly into target host cells. These effectors cooperatively manipulate multiple host cell signaling pathways to drive pathogen internalization. Salmonella does not only rely on these injected effectors, but also uses several other T3SS-independent mechanisms to gain entry into host cells. This review summarizes our current understanding of the methods used by Salmonella for cell invasion, with a focus on the host signaling networks that must be coordinately exploited for the pathogen to achieve its goal.

  8. Persistence of salmonella typhimurium in nopal cladodes

    Science.gov (United States)

    Fresh produce associated outbreaks have increased in the last few years. E.coli O157:H7 and Salmonella have been causative agents of infection in these outbreaks. Fresh produce is consumed raw, and in the absence of terminal kill treatment, it is imperative to understand sources of contamination o...

  9. Water Frogs, Aquariums, and Salmonella -- Oh My!

    Centers for Disease Control (CDC) Podcasts

    2009-12-09

    This CDC Kidtastics podcast discusses how people can get Salmonella from water frogs and aquariums.  Created: 12/9/2009 by National Center for Zoonotic, Vector-Borne, and Enteric Diseases (NCZVED).   Date Released: 12/9/2009.

  10. Persistence of salmonella Typhimurium in Nopal

    Science.gov (United States)

    Having documented information available on the capability of Salmonella to remain in the cladode tissue it is important to understand the role of nopal on the lifecycle of enteropathogenic bacteria in humans, as well as for management and control programs of theses pathogens in plants. Because of th...

  11. Antimicrobial susceptibility of Salmonella enterica strains isolated ...

    African Journals Online (AJOL)

    SARAH

    2015-11-30

    Nov 30, 2015 ... (n=50) and sheep intestine (n=50) were analyzed using standards microbiological method for ... handlers are still observed during food marketing ... was conducted according to ISO 6579: 2002 (E) methods ..... from local beverages (bissap, gnamakoudji) sold ... Salmonella isolated from children under five.

  12. Inhibition of Escherichia Coli, Salmonella and Staphylococcus ...

    African Journals Online (AJOL)

    Escherichia coli O157:H7, Salmonella typhimurium and Staphylococcus. aureus are of great concern to the food industry, especially in foods stored under refrigerated conditions where, unlike most food-borne pathogens are able to multiply. This investigation was conducted to study the inhibitory effect of some spice ...

  13. Thirteenth CRL-Salmonella interlaboratory comparison study on typing of Salmonella spp. : Dertiende CRL-Salmonella ringonderzoek voor de typering van Salmonella spp.

    NARCIS (Netherlands)

    Berk PA; Maas HME; de Pinna E; Mooijman KA; LZO; cib

    2010-01-01

    De Nationale Referentie Laboratoria (NRL's) van de 27 Europese lidstaten scoorden goed bij de kwaliteitscontrole op Salmonella-typering in 2008. Vier laboratoria hadden hiervoor een herkansing nodig. Daarnaast is een analyse van alle NRL's als groep uitgevoerd, waaruit bleek dat zij 97 % van de

  14. Colicinogeny in Salmonella serovars isolated in Brazil

    Directory of Open Access Journals (Sweden)

    Leila Carvalho Campos

    1988-06-01

    Full Text Available A study of colicinogeny was made in 748 strains of Salmonella (97 serovars isolated from different sources; human (291, animal (119, environmental (141, food (102 and animal feed (95. Colicin production was detected in 64 strains (8.6%, particularly isolated from foods (30.4%. Col. E1 (53 and Ia (44 were the most frequently observed, especially in S. agona for environment and food sources. Col V production was identified in 5 strains of S. typhimurium within 8 producer cultures isolated from humans. Its relationship with the sources and serovars of Salmonella are discussed.Investigou-se a produção de colicina em 748 amostras de Salmonella (97 sorovares advindas de díferentes fontes: humana (291, animal (119, ambiental (141, de alimentos (102 e rações (95. Detectaram-se 64 amostras (8,6% colicinogênicas, particularmente isoladas de alimentos (30,4%. ColE1 (53 e Ia (44 foram as mais freqüentes, especialmente no sorovar S, agona, de origem ambiental e de alimentos. Identificou-se também a produção de col V em 5 amostras de S. typhimurium dentre 8 culturas produtoras de origem humana. Discute-se a relação entre a capacidade colicinogênica e as fontes e sorovares de Salmonella.

  15. Sixteenth EURL-Salmonella interlaboratory comparison study on typing of Salmonella spp. : Zestiende EURL-Salmonella ringonderzoek voor de typering van Salmonella spp.

    NARCIS (Netherlands)

    Jacobs-Reitsma WF; Pol-Hofstad IE; Maas HME; de Pinna E; Mooijman KA; LZO; cib

    2012-01-01

    De 28 Nationale Referentie Laboratoria (NRL's) van de 27 Europese lidstaten scoorden in 2011 goed bij de kwaliteitscontrole om Salmonella te typeren. Twee laboratoria hadden hiervoor een herkansing nodig. Alle NRL's samen konden gemiddeld genomen aan 97 procent van de geteste stammen de juiste naam

  16. drug resistant strains of Salmonella enterica

    African Journals Online (AJOL)

    Conclusions: The aqueous extract of Thonningia sanguinea can provide an alternative therapy for the treatment of salmonellosis, mainly for typhoid fever caused by MDR strains of S. Typhi.The extract also inhibits S.Hadar a MDR emerging strain in Ivory Coast. Keywords: Thonningia sanguinea; Salmonella, MDR strains, ...

  17. Attachment of Salmonella spp. to pork meat

    DEFF Research Database (Denmark)

    Hansen, Trine; Riber, Leise; Löfström, Charlotta

    2011-01-01

    Five strains of Salmonella, one wildtype and four knock-out mutants (the prg, flhDC, yhjH and fliC genes) were investigated based on their probability to attach and subsequently detach from a surface of pork fillet. The attachment followed by detachment was measured and modelled for two different...

  18. Salmonella typhi time to change empiric treatment

    DEFF Research Database (Denmark)

    Gade, C.; Engberg, J.; Weis, N.

    2008-01-01

    In the present case series report we describe seven recent cases of typhoid fever. All the patients were travellers returning from Pakistan, where typhoid is endemic. Salmonella typhi isolated from the patients by blood culture were reported as intermediary susceptible to fluoroquinolones in six...

  19. Effect of Salmonella thyphymurium Infection on the ...

    African Journals Online (AJOL)

    This study was designed to investigate the effect of Salmonella thyphimurium infection on the plasma kinetics of ceftriaxone in Sokoto red goats. In a randomised two-way study, 10 healthy male goats were divided into two groups of five each, and either received a single intramuscular (IM) injection of 1g ceftriaxone only or ...

  20. Incidence and antimicrobial susceptibility pattern of salmonella ...

    African Journals Online (AJOL)

    A study was carried out to investigate the incidence of Salmonella species among 300 children using stool samples from six hospitals in the metropolitan Kano. The organisms were investigated using cultural, serological biochemical characterization and sensitivity to some antimicrobial agents. The incidence of the bacteria ...

  1. Fate of Salmonella Species and E

    African Journals Online (AJOL)

    user

    determining the growth potential of some food-borne pathogens in the juices at different holding temperatures. ... 3Institute of Pathology, Addis Ababa University P.O. Box 1176, Addis Ababa, Ethiopia ... Bacteriology laboratory, Ethiopian Health .... food poisoning caused by Salmonella .... Antiviral effect of commercial juices.

  2. Salmonella osteomyelitis by sickle cell anemia

    International Nuclear Information System (INIS)

    Rausch, H.; Tran, V.T.; Boeckmann, U.; Duesseldorf Univ.

    1985-01-01

    Case report of a 28 year old black sickle cell anemia patient with salmonella osteomyelitis of the radius. Aside from sickle cell anemia patients this skeletal complication of enteric salmonellosis is an extreme rarity. Description of the typical roentgenological features includes intracortical fissures and sequestration. (orig.) [de

  3. Effect of Antimicrobials on Salmonella Spp. Strains Isolated from Poultry Processing Plants

    Directory of Open Access Journals (Sweden)

    L Mion

    Full Text Available ABSTRACT The routine use of antimicrobials in animal production for the treatment of infections, disease prevention, or as growth promoters is a predisposing factor for the development and dissemination of antimicrobial resistance. In food industries, sanitizers are used for the control of microbial colonization, and their efficacy depends on contact time and on the dilution of the products used. The present study assessed the effect of 12 antimicrobials and four commercial sanitizers on 18 Salmonella spp. strains isolated from poultry processing plants. None of the evaluated antimicrobials was 100% effective against the tested Salmonella spp. strains; however, 94% of the isolates were susceptible to ciprofloxacin, 77% to amoxicillin + clavulanic acid and to ampicillin, and 72% to enrofloxacin, whereas 100% of the isolates were resistant to penicillin G, 16% to tetracycline, and 11% to sulfonamide. The tested Salmonella spp. strains were 100% inhibited by peracetic acid after five minutes of contact, 0.5% by quaternary ammonium after 15 minutes, and 85.7% by chlorhexidine after 15 minutes. The results indicate the importance of testing of efficacy of antimicrobials used in animal production and in public health to monitor their action and the development of resistance.

  4. Destruction of Salmonellae on poultry meat with lysozyme, EDTA, x ray, microwave, and chlorine

    International Nuclear Information System (INIS)

    Teotia, J.S.; Miller, B.F.

    1975-01-01

    Lysozyme, ethylenediaminetetracetic acid, chlorine, x-irradiation and microwaves were used in experimental attempts to eliminate Salmonella senftenberg 775W or Salmonella typhimurium from turkey drumsticks and whole carcasses. Turkey drumsticks or whole carcasses were artificially contaminated with S. senfenberg 775W or S. typhimurium in concentrations ranging between 5 x 10 5 to 8 x 10 5 viable cells per ml. of contaminating fluid. After each treatment, samples were cultured, plated, and tested according to standard methods to determine the susceptibility of Salmonella organisms to the particular treatment. A 0.1 percent solution of lysozyme eliminated the S. senftenberg 775W at 22 0 C within three hours. A 0.5 percent solution of ethylenediaminetetracetic acid failed to destroy the test organism under the same conditions. Eighty thousand rads of X-ray eliminated the test organism on turkey drumsticks but failed to remove it from whole turkey carcasses. Microwaves eliminated the S. senftenberg 775W in 150 seconds from turkey drumsticks and ten minutes from broiler chicken carcasses. Aqueous solutions containing 3400 and 2125 ppM chlorine failed to destroy the test organism on turkey drumsticks at 21 0 C. in 9 and 24 hours. None of the treatments changed the appearance of the skin or meat, except microwaves produced a partially-cooked appearance. Chlorine produced off-color drumsticks

  5. Incidence of Salmonella contamination in broiler chickens in Saskatchewan.

    Science.gov (United States)

    Bhargava, K K; O'Neil, J B; Prior, M G; Dunkelgod, K E

    1983-01-01

    The incidence of Salmonella contamination in ten Saskatchewan broiler flocks varying in size from 6 200 to 14 000 was investigated from February, 1977 to April, 1979. Prior to the initial chick placement, brooding equipment, feed, water and fresh litter samples were found to be free of Salmonellae. Samples obtained from the clean and disinfected processing plant equipment before the commencement of daily operation were negative except the isolation for Salmonella anatum from the fingers of the defeathering machine in flock 4. There was no evidence of Salmonella contamination in flocks 5, 6, 8 and 10. The incidence of Salmonella was lower when cloacal swabs were taken from day old chicks fasted for 48 hours than for the same groups of chicks when carcasses were blended in nutrient broth (flocks 7 and 9). The blending of such chicks appears to be a more critical test. The serotypes isolated from eviscerated birds were the same as those isolated from used litter samples. Salmonella saintpaul was isolated from a water sample at 53 days in flock 1 and the same serotype was recovered from the intestinal contents and skin of eviscerated birds. Salmonella typhimurium was recovered from the eviscerated birds and neck samples in flock 3. In flock 4, S. saintpaul and S. anatum were isolated from 13% of the eviscerated birds sampled. Salmonella thompson, Salmonella agona and Salmonella heidelberg were recovered from 61%, 5% and 1%, respectively, of the processed carcasses sampled in flock 7.

  6. Radiosensitization of Escherichia coli and Salmonella typhi in presence of active compounds

    International Nuclear Information System (INIS)

    Lacroix, M.; Chiasson, F.; Borsa, J.; Ouattara, B.

    2004-01-01

    The radiosensitization of Escherichia coli and Salmonella typhi in ground beef was evaluated in the presence of 18 active compounds. Medium fat ground beef (23% fat) was inoculated with E. coli or S. typhi and each active compound was added separately at various concentrations. For E. coli, the most efficient compounds were trans-cinnamaldehyde, thymol and thyme. For S. typhi, the most efficient compounds was trans-cinnamaldehyde, carvacrol and thymol. The addition of tetrasodium pyrophosphate, carvacrol and ascorbic acid had no effect on the irradiation sensitivity of E. coli. For S. typhi, only ascorbic acid had no effect

  7. Radiosensitization of Escherichia coli and Salmonella typhi in presence of active compounds

    Energy Technology Data Exchange (ETDEWEB)

    Lacroix, M. E-mail: monique.lacroix@inrs-iaf.uquebec.ca; Chiasson, F.; Borsa, J.; Ouattara, B

    2004-10-01

    The radiosensitization of Escherichia coli and Salmonella typhi in ground beef was evaluated in the presence of 18 active compounds. Medium fat ground beef (23% fat) was inoculated with E. coli or S. typhi and each active compound was added separately at various concentrations. For E. coli, the most efficient compounds were trans-cinnamaldehyde, thymol and thyme. For S. typhi, the most efficient compounds was trans-cinnamaldehyde, carvacrol and thymol. The addition of tetrasodium pyrophosphate, carvacrol and ascorbic acid had no effect on the irradiation sensitivity of E. coli. For S. typhi, only ascorbic acid had no effect.

  8. Salmonella spp. on chicken carcasses in processing plants in Poland.

    Science.gov (United States)

    Mikołajczyk, Anita; Radkowski, Mieczysław

    2002-09-01

    Chickens at selected points in the slaughter process and after slaughter on the dressing line in poultry plants were sampled and analyzed for Salmonella. These chickens came from the northeast part of Poland. The examinations were carried out in quarters I, II, III, and IV of 1999. All the birds were determined to be healthy by a veterinary inspection. Swab samples were taken from the cloaca after stunning and from the skin surface and body cavity of the whole bird after evisceration, after rinsing at the final rinse station but before chilling in the spin-chiller, and after cooling in the continuous cooling plant at the end of the production day. In 1999, 400 whole chickens were examined. The percentage of these 400 chickens from which Salmonella spp. were isolated was relatively high (23.75%; Salmonella-positive results were observed in 95 cases). Salmonella spp. were found after stunning in 6% of the chickens (6 of 100 samples), after evisceration in 24% (24 of 100), before cooling in 52% (52 of 100), and after cooling in 13% (13 of 100). These results show that Salmonella spp. were found more often at some processing points than at others. The lowest Salmonella spp. contamination rate (6%) for slaughter birds was found after stunning, and the highest contamination rate was found before chilling (52%). The serological types of Salmonella spp. isolated from whole chickens were Salmonella Enteritidis, Salmonella Typhimurium, Salmonella Saintpaul, Salmonella Agona, and Salmonella Infantis. The results of these investigations indicate that Salmonella Enteritidis is the dominant serological type in infections of slaughter chickens, as it is in many countries.

  9. Prevalence of antimicrobial resistance among Salmonella isolates from chicken in China.

    Science.gov (United States)

    Lu, Yan; Wu, Cong-Ming; Wu, Guo-Juan; Zhao, Hong-Yu; He, Tao; Cao, Xing-Yuan; Dai, Lei; Xia, Li-Ning; Qin, Shang-Shang; Shen, Jian-Zhong

    2011-01-01

    We evaluated the antimicrobial resistance of Salmonella isolated in 2008 from a chicken hatchery, chicken farms, and chicken slaughterhouses in China. A total of 311 Salmonella isolates were collected from the three sources, and two serogroups of Salmonella were detected, of which 133 (42.8%) consisted of Salmonella indiana and 178 (57.2%) of Salmonella enteritidis. The lowest percentage of S. indiana isolates was found in the chicken hatchery (4.2%), followed by the chicken farms (54.9%) and the slaughterhouses (71.4%). More than 80% of the S. indiana isolates were highly resistant to ampicillin (97.7%), amoxicillin/clavulanic acid (87.9%), cephalothin (87.9%), ceftiofur (85.7%), chloramphenicol (84.9%), florfenicol (90.9%), tetracycline (97.7%), doxycycline (98.5%), kanamycin (90.2%), and gentamicin (92.5%). About 60% of the S. indiana isolates were resistant to enrofloxacin (65.4%), norfloxacin (78.9%), and ciprofloxacin (59.4%). Of the S. indiana isolates, 4.5% were susceptible to amikacin and 5.3% to colistin. Of the S. enteritidis isolates, 73% were resistant to ampicillin, 33.1% to amoxicillin/clavulanic acid, 66.3% to tetracycline, and 65.3% to doxycycline, whereas all of these isolates were susceptible to the other drugs used in the study. The S. indiana isolates showed resistance to 16 antimicrobial agents. Strains of Salmonella (n = 108) carrying the resistance genes floR, aac(6')-Ib-cr, and bla(TEM) were most prevalent among the 133 isolates of S. indiana, at a frequency of 81.2%. The use of pulsed-field gel electrophoresis to analyze the S. indiana isolates that showed similar antimicrobial resistance patterns and carried resistance genes revealed six genotypes of these organisms. Most of these isolates had the common pulsed-field gel electrophoresis patterns found in the chicken hatchery, chicken farms, and slaughterhouses, suggesting that many multidrug-resistant isolates of S. indiana prevailed in the three sources. Some of these isolates were

  10. 76 FR 41157 - Guidance for Industry: Questions and Answers Regarding the Final Rule, Prevention of Salmonella...

    Science.gov (United States)

    2011-07-13

    ..., Prevention of Salmonella Enteritidis in Shell Eggs During Production, Storage, and Transportation... Industry: Questions and Answers Regarding the Final Rule, Prevention of Salmonella Enteritidis in Shell... Salmonella Enteritidis in Shell Eggs During Production, Storage, and Transportation'' (the final rule). The...

  11. 75 FR 18849 - Small Entity Compliance Guide: Prevention of Salmonella Enteritidis in Shell Eggs During...

    Science.gov (United States)

    2010-04-13

    ...] Small Entity Compliance Guide: Prevention of Salmonella Enteritidis in Shell Eggs During Production... ``Prevention of Salmonella Enteritidis in Shell Eggs During Production, Storage, and Transportation--Small... requiring shell egg producers to implement measures to prevent Salmonella Enteritidis (SE) from...

  12. Comparing human-Salmonella with plant-Salmonella protein-protein interaction predictions

    Directory of Open Access Journals (Sweden)

    Sylvia eSchleker

    2015-01-01

    Full Text Available Salmonellosis is the most frequent food-borne disease world-wide and can be transmitted to humans by a variety of routes, especially via animal and plant products. Salmonella bacteria are believed to use not only animal and human but also plant hosts despite their evolutionary distance. This raises the question if Salmonella employs similar mechanisms in infection of these diverse hosts. Given that most of our understanding comes from its interaction with human hosts, we investigate here to what degree knowledge of Salmonella-human interactions can be transferred to the Salmonella-plant system. Reviewed are recent publications on analysis and prediction of Salmonella-host interactomes. Putative protein-protein interactions (PPIs between Salmonella and its human and Arabidopsis hosts were retrieved utilizing purely interolog-based approaches in which predictions were inferred based on available sequence and domain information of known PPIs, and machine learning approaches that integrate a larger set of useful information from different sources. Transfer learning is an especially suitable machine learning technique to predict plant host targets from the knowledge of human host targets. A comparison of the prediction results with transcriptomic data shows a clear overlap between the host proteins predicted to be targeted by PPIs and their gene ontology enrichment in both host species and regulation of gene expression. In particular, the cellular processes Salmonella interferes with in plants and humans are catabolic processes. The details of how these processes are targeted, however, are quite different between the two organisms, as expected based on their evolutionary and habitat differences. Possible implications of this observation on evolution of host-pathogen communication are discussed.

  13. Recent Trends in Salmonella Outbreaks and Emerging Technology for Biocontrol of Salmonella Using Phages in Foods: A Review.

    Science.gov (United States)

    Oh, Jun-Hyun; Park, Mi-Kyung

    2017-12-28

    Salmonella is one of the principal causes of foodborne outbreaks. As traditional control methods have shown less efficacy against emerging Salmonella serotypes or antimicrobialresistant Salmonella , new approaches have been attempted. The use of lytic phages for the biocontrol of Salmonella in the food industry has become an attractive method owing to the many advantages offered by the use of phages as biocontrol agents. Phages are natural alternatives to traditional antimicrobial agents; they have proven effective in the control of bacterial pathogens in the food industry, which has led to the development of different phage products. The treatment with specific phages in the food industry can prevent the decay of products and the spread of bacterial diseases, and ultimately promotes safe environments for animal and plant food production, processing, and handling. After an extensive investigation of the current literature, this review focuses predominantly on the efficacy of phages for the successful control of Salmonella spp. in foods. This review also addresses the current knowledge on the pathogenic characteristics of Salmonella , the prevalence of emerging Salmonella outbreaks, the isolation and characterization of Salmonella -specific phages, the effectiveness of Salmonella -specific phages as biocontrol agents, and the prospective use of Salmonella -specific phages in the food industry.

  14. Prevalence, serovars and antimicrobial susceptibility of Salmonella spp. from wild and domestic green iguanas (Iguana iguana) in Grenada, West Indies.

    Science.gov (United States)

    Sylvester, W R B; Amadi, V; Pinckney, R; Macpherson, C N L; McKibben, J S; Bruhl-Day, R; Johnson, R; Hariharan, H

    2014-09-01

    Cloacal swabs from 62 green iguanas (Iguana iguana), including 47 wild and 15 domestic ones from five parishes of Grenada, were sampled during a 4-month period of January to April 2013 and examined by enrichment and selective culture for the presence of Salmonella spp. Fifty-five per cent of the animals were positive, and eight serovars of Salmonella were isolated. The most common serovar was Rubislaw (58.8%), a serovar found recently in many cane toads in Grenada, followed by Oranienburg (14.7%), a serovar that has been causing serious human disease outbreaks in Japan. Serovar IV:48:g,z51 :- (formerly, S. Marina) highly invasive and known for serious infections in children in the United States, constituted 11.8% of the isolates, all of them being from domestic green iguanas. Salmonella Newport, a serovar recently found in a blue land crab in Grenada, comprised 11.8% of the isolates from the green iguanas. The remaining four less frequent serovars included S. Javiana and S. Glostrup. Antimicrobial susceptibility tests conducted by a disc diffusion method against amoxicillin-clavulanic acid, ampicillin, cefotaxime, ceftazidime, ciprofloxacin, enrofloxacin, gentamicin, nalidixic acid, streptomycin, tetracycline and trimethoprim-sulfamethoxazole showed that drug resistance is minimal, with intermediate susceptibility, mainly to streptomycin, tetracycline and cefotaxime. This is the first report of isolation and antimicrobial susceptibilities of various Salmonella serovars from wild and domestic green iguanas in Grenada, West Indies. © 2013 Blackwell Verlag GmbH.

  15. Genotypic relatedness and antimicrobial resistance of Salmonella Heidelberg isolated from chickens and turkeys in the midwestern United States.

    Science.gov (United States)

    Nisar, Muhammad; Kassem, Issmat I; Rajashekara, Gireesh; Goyal, Sagar M; Lauer, Dale; Voss, Shauna; Nagaraja, Kakambi V

    2017-05-01

    Salmonella is one of the most common causes of foodborne illnesses in humans in the United States, and domestic poultry is considered an important source of this pathogen. Salmonella enterica subsp. enterica serovar Heidelberg is the fourth most commonly reported Salmonella from retail meats and food animals in the United States. We assessed the genotypes and antimicrobial resistance phenotypes of Salmonella Heidelberg isolated from various chicken and turkey hatcheries and breeder farms in the Midwest. The genotypes of 33 S. Heidelberg isolates from chickens ( n = 19) and turkeys ( n = 14) were compared using pulsed-field gel electrophoresis analysis. Cluster analysis of the fingerprints showed that the majority of the chicken isolates grouped together with 87% similarity; those from turkeys clustered with 88% similarity. Similarity between chicken and turkey isolates was also high (86%). Isolates from turkeys were generally more genetically diverse than those from chickens. Antimicrobial susceptibility analysis detected resistance to sulfisoxazole (36% of the isolates), streptomycin (33%), gentamicin (27%), tetracycline (24%), ampicillin and amoxicillin-clavulanic acid (15%), cefoxitin (12%), ceftriaxone and ceftiofur (12%), and chloramphenicol (9%). None of the isolates was resistant to azithromycin, ciprofloxacin, or nalidixic acid. Although the number of the isolates was limited in our study, we conclude that S. Heidelberg isolates from the same host generally clustered together and that a considerable number of the isolates were resistant to a number of antimicrobial agents.

  16. Prevalence and Diversity of Salmonella Serotypes in Ecuadorian Broilers at Slaughter Age.

    Directory of Open Access Journals (Sweden)

    Christian Vinueza-Burgos

    Full Text Available Salmonella is frequently found in poultry and represent an important source for human gastrointestinal infections worldwide. The aim of this study was to investigate the prevalence, genotypes and antimicrobial resistance of Salmonella serotypes in broilers from Ecuador. Caeca content from 388 at random selected broiler batches were collected in 6 slaughterhouses during 1 year and analyzed by the ISO 6579/Amd1 protocol for the isolation for Salmonella. Isolates were serotyped and genotypic variation was acceded by pulsed field gel electrophoresis. MIC values for sulfamethoxazole, gentamicin, ciprofloxacin, ampicillin, cefotaxime, ceftazidime, tetracycline, streptomycin, trimethropim, chloramphenicol, colistin, florfenicol, kanamycin and nalidixic acid were obtained. Presence of blaCTX-M, blaTEM, blaSHV and blaCMY; and mcr-1 plasmid genes was investigated in resistant strains to cefotaxime and colistin respectively. Prevalence at batch level was 16.0%. The most common serotype was S. Infantis (83.9% followed by S. Enteritidis (14.5% and S. Corvallis (1.6%. The pulsed field gel electrophoresis analysis showed that S. Corvallis, S. Enteritidis and S. Infantis isolates belonged to 1, 2 and 12 genotypes respectively. S. Infantis isolates showed high resistance rates to 12 antibiotics ranging from 57.7% (kanamycin up to 98.1% (nalidixic acid and sulfamethoxazole. All S. Enteritidis isolates showed resistance to colistin. High multiresistant patterns were found for all the serotypes. The blaCTX-M gene was present in 33 S. Infantis isolates while mcr-1 was negative in 10 colistin resistant isolates. This study provides the first set of scientific data on prevalence and multidrug-resistant Salmonella coming from commercial poultry in Ecuador.

  17. Lactobacillus bulgaricus, Lactobacillus rhamnosus and Lactobacillus paracasei Attenuate Salmonella Enteritidis, Salmonella Heidelberg and Salmonella Typhimurium Colonization and Virulence Gene Expression In Vitro.

    Science.gov (United States)

    Muyyarikkandy, Muhammed Shafeekh; Amalaradjou, Mary Anne

    2017-11-09

    Salmonella Enteritidis (SE), Salmonella Typhimurium (ST), and Salmonella Heidelberg (SH) have been responsible for numerous outbreaks associated with the consumption of poultry meat and eggs. Salmonella colonization in chicken is characterized by initial attachment to the cecal epithelial cells (CEC) followed by dissemination to the liver, spleen, and oviduct. Since cecal colonization is critical to Salmonella transmission along the food chain continuum, reducing this intestinal association could potentially decrease poultry meat and egg contamination. Hence, this study investigated the efficacy of Lactobacillus delbreuckii sub species bulgaricus (NRRL B548; LD), Lactobacillus paracasei (DUP-13076; LP), and Lactobacillus rhamnosus (NRRL B442; LR) in reducing SE, ST, and SH colonization in CEC and survival in chicken macrophages. Additionally, their effect on expression of Salmonella virulence genes essential for cecal colonization and survival in macrophages was evaluated. All three probiotics significantly reduced Salmonella adhesion and invasion in CEC and survival in chicken macrophages ( p < 0.05). Further, the probiotic treatment led to a significant reduction in Salmonella virulence gene expression ( p < 0.05). Results of the study indicate that LD, LP, and LR could potentially be used to control SE, ST, and SH colonization in chicken. However, these observations warrant further in vivo validation.

  18. Lactobacillus bulgaricus, Lactobacillus rhamnosus and Lactobacillus paracasei Attenuate Salmonella Enteritidis, Salmonella Heidelberg and Salmonella Typhimurium Colonization and Virulence Gene Expression In Vitro

    Directory of Open Access Journals (Sweden)

    Muhammed Shafeekh Muyyarikkandy

    2017-11-01

    Full Text Available Salmonella Enteritidis (SE, Salmonella Typhimurium (ST, and Salmonella Heidelberg (SH have been responsible for numerous outbreaks associated with the consumption of poultry meat and eggs. Salmonella colonization in chicken is characterized by initial attachment to the cecal epithelial cells (CEC followed by dissemination to the liver, spleen, and oviduct. Since cecal colonization is critical to Salmonella transmission along the food chain continuum, reducing this intestinal association could potentially decrease poultry meat and egg contamination. Hence, this study investigated the efficacy of Lactobacillus delbreuckii sub species bulgaricus (NRRL B548; LD, Lactobacillus paracasei (DUP-13076; LP, and Lactobacillus rhamnosus (NRRL B442; LR in reducing SE, ST, and SH colonization in CEC and survival in chicken macrophages. Additionally, their effect on expression of Salmonella virulence genes essential for cecal colonization and survival in macrophages was evaluated. All three probiotics significantly reduced Salmonella adhesion and invasion in CEC and survival in chicken macrophages (p < 0.05. Further, the probiotic treatment led to a significant reduction in Salmonella virulence gene expression (p < 0.05. Results of the study indicate that LD, LP, and LR could potentially be used to control SE, ST, and SH colonization in chicken. However, these observations warrant further in vivo validation.

  19. Conservation of Salmonella infection mechanisms in plants and animals.

    Directory of Open Access Journals (Sweden)

    Adam Schikora

    Full Text Available Salmonella virulence in animals depends on effectors injected by Type III Secretion Systems (T3SSs. In this report we demonstrate that Salmonella mutants that are unable to deliver effectors are also compromised in infection of Arabidopsis thaliana plants. Transcriptome analysis revealed that in contrast to wild type bacteria, T3SS mutants of Salmonella are compromised in suppressing highly conserved Arabidopsis genes that play a prominent role during Salmonella infection of animals. We also found that Salmonella originating from infected plants are equally virulent for human cells and mice. These results indicate a high degree of conservation in the defense and infection mechanism of animal and plant hosts during Salmonella infection.

  20. Modeling salmonella Dublin into the dairy herd simulation model Simherd

    DEFF Research Database (Denmark)

    Kudahl, Anne Braad

    2010-01-01

    Infection with Salmonella Dublin in the dairy herd and effects of the infection and relevant control measures are currently being modeled into the dairy herd simulation model called Simherd. The aim is to compare the effects of different control strategies against Salmonella Dublin on both within...... of the simulations will therefore be used for decision support in the national surveillance and eradication program against Salmonella Dublin. Basic structures of the model are programmed and will be presented at the workshop. The model is in a phase of face-validation by a group of Salmonella......-herd- prevalence and economy by simulations. The project Dublin on both within-herd- prevalence and economy by simulations. The project is a part of a larger national project "Salmonella 2007 - 2011" with the main objective to reduce the prevalence of Salmonella Dublin in Danish Dairy herds. Results...

  1. In vitro selection of RNA aptamer specific to Salmonella typhimurium.

    Science.gov (United States)

    Han, Seung Ryul; Lee, Seong-Wook

    2013-06-28

    Salmonella is a major foodborne pathogen that causes a variety of human diseases. Development of ligands directly and specifically binding to the Salmonella will be crucial for the rapid detection of, and thus for efficient protection from, the virulent bacteria. In this study, we identified a RNA aptamer-based ligand that can specifically recognize Salmonella Typhimurium through SELEX technology. To this end, we isolated and characterized an RNase-resistant RNA aptamer that bound to the OmpC protein of Salmonella Typhimurium with high specificity and affinity (Kd ~ 20 nM). Of note, the selected aptamer was found to specifically bind to Salmonella Typhimurium, but neither to Gram-positive bacteria (Staphylococcus aureus) nor to other Gram-negative bacteria (Escherichia coli O157:H7). This was evinced by aptamer-immobilized ELISA and aptamer-linked precipitation experiments. This Salmonella species-specific aptamer could be useful as a diagnostic ligand against pathogen-caused foodborne sickness.

  2. Effect of acidified drinking water on the recovery of Salmonella enteritidis from broiler crops

    Directory of Open Access Journals (Sweden)

    Avila LAF de

    2003-01-01

    Full Text Available Crop is a known source of Salmonella contamination during broiler carcass processing. The effect of drinking water acidification by lactic acid or citric acid or a combination of those with cupric sulfate and d-limonene in the reduction of Salmonella Enteritidis (SE recovered from the crop of broilers was evaluated. Treatments were administered during 8 hours of preslaughter fasting period (Experiments I and II and during the last 32 hours of preslaughter (Experiment III. It was observed that acidification reduced water intake when treatments began at preslaughter feed withdrawal, and affected the possible reducing effect of these acids on SE recovering (Experiments I and II. Water intake during preslaughter feed withdrawal was not affected when treatment began 32 hours before slaughter (Experiment III. Treatments reduced SE recovering from crop (p<0.05. In Experiment III, 0.470% of lactic acid reduced the number of recovered SE in 99%. This study suggested that the addition of organic acids in the drinking water 24 hours before beginning the preslaughter feed withdrawal might reduce crop SE colonization and might be an important strategy to reduce SE contamination of broiler products during processing.

  3. Availability of Amino Acids Extends Chronological Lifespan by Suppressing Hyper-Acidification of the Environment in Saccharomyces cerevisiae.

    Directory of Open Access Journals (Sweden)

    Yo Maruyama

    Full Text Available The chronological lifespan of Saccharomyces cerevisiae represents the duration of cell survival in the postdiauxic and stationary phases. Using a prototrophic strain derived from the standard auxotrophic laboratory strain BY4742, we showed that supplementation of non-essential amino acids to a synthetic defined (SD medium increases maximal cell growth and extends the chronological lifespan. The positive effects of amino acids can be reproduced by modulating the medium pH, indicating that amino acids contribute to chronological longevity in a cell-extrinsic manner by alleviating medium acidification. In addition, we showed that the amino acid-mediated effects on extension of chronological longevity are independent of those achieved through a reduction in the TORC1 pathway, which is mediated in a cell-intrinsic manner. Since previous studies showed that extracellular acidification causes mitochondrial dysfunction and leads to cell death, our results provide a path to premature chronological aging caused by differences in available nitrogen sources. Moreover, acidification of culture medium is generally associated with culture duration and cell density; thus, further studies are required on cell physiology of auxotrophic yeast strains during the stationary phase because an insufficient supply of essential amino acids may cause alterations in environmental conditions.

  4. Evolution of antimicrobial resistance of Salmonella enteritidis (1972–2005

    Directory of Open Access Journals (Sweden)

    Jermaine Khumalo

    2014-11-01

    Full Text Available With the extensive use of antibiotics in livestock production, surveillance revealed an increase in Salmonella resistance to the commonly used antimicrobials in veterinary and public health. This serious threat to health care is further exacerbated by the limited epidemiological information about the common zoonotic agent, Salmonella enteritidis, required to determine antibiotic therapy. The aim was to characterise the antimicrobial resistance patterns of S. enteritidis isolates across different timelines (1972–2005 with accompanying genetic changes being investigated. Thirty-seven stored S. enteritidis isolates were collected from the Central Veterinary Laboratory, Harare, with antimicrobial susceptibility determined against eight antibiotics. Plasmids were isolated to analyse any genetic variation. An overall significant increase in resistance (p < 0.05 to nalidixic acid (0% – 10%, ampicillin (14.3% – 50%, tetracycline (14.3% – 30% and erythromycin (71.4% – 100% was observed across the timeline. However, the highest rates of susceptibility were maintained for gentamicin, sulphamethoxazole-trimethoprim, kanamycin and chloramphenicol. We report an increase in multidrug resistance (MDR of 14.2% – 50% with an increase in resistotypes and plasmid profiles across the timeline. Eleven plasmid profiles were obtained in the 37 isolates studied with a minority of isolates (21.6%, 8/37 harbouring a 54 kb plasmid, commonly serovar-specific. A concerning increase in antimicrobial resistance to commonly administered drugs was observed across the timeline. The surge in MDR is of great concern and implies the need for consistent antimicrobial stewardship. No correlation was observed between the plasmid and antibiotic profiles.

  5. Salmonella isolates from wild-caught Tokay geckos (Gekko gecko) imported to the U.S. from Indonesia.

    Science.gov (United States)

    Smith, Katherine F; Yabsley, Michael J; Sanchez, Susan; Casey, Christine L; Behrens, Michael D; Hernandez, Sonia M

    2012-07-01

    Reptiles account for ∼10% of live animal shipments imported to the United States (U.S.), the majority of which are sold in the pet trade. Characterizing Salmonella shedding by imported reptiles is of value to public health, the pet industry, and veterinary medicine. Here we report results of a pilot survey of Salmonella serotypes isolated from wild-caught Indonesian Tokay geckos (Gekko gecko) imported to the U.S. Upon arrival, the geckos were individually housed until a fecal sample was acquired for Salmonella culture. The geckos were divided into three groups with variable numbers to investigate density effects. A second group was imported after 3 months and combined with the previous groups. A total of 88 Salmonella isolates were obtained from 110 geckos surveyed, representing 14 serogroups and 17 unique serotypes. Group prevalence ranged from 31-73%. A significant increase in prevalence and a change in serotype richness were detected between the time of import and 6 months later at necropsy. Six isolates (6.8%) expressed resistance to more than one antibiotic. All S. enterica subsp. enterica Adelaide isolates were resistant to nalidixic acid and sulfisoxazole, one S. enterica subsp. arizonae 61:k:z35 isolate was resistant to ampicillin and sulfisoxazole, and another 61:k:z35 isolate was resistant to streptomycin and sulfisoxazole. Forty-three additional isolates expressed resistance only to sulfisoxazole. The mechanisms for increased prevalence and apparent change in serotype richness are unknown, but could be due to stress associated with trade, transport, and captivity, increased transmission from unnaturally high densities, or contact with other species shedding Salmonella along the trade route. Future studies to differentiate the physical, social, and physiological effects of trade-related conditions on Salmonella shedding and transmission among reptiles will benefit the industry by identifying ways to reduce mortality, and safeguard the individuals

  6. Molecular detection of Salmonella spp. isolated from apparently healthy pigeon in Mymensingh, Bangladesh and their antibiotic resistance pattern

    Directory of Open Access Journals (Sweden)

    Md. Khaled Saifullah

    2016-03-01

    Full Text Available Objectives: Here we determined the prevalence of Salmonella in cloacal swabs and pharyngeal swabs of apparently healthy pigeons sold in the live bird markets and villages in and around Bangladesh Agricultural University Campus, Mymensingh, Bangladesh. Materials and methods: A total of 50 samples, comprised of cloacal swabs (n=24 and pharyngeal swabs (n=26 were collected. The samples were processed, and Salmonella was isolated through a series of conventional bacteriological techniques and biochemical tests followed by polymerase chain reaction (PCR. Results: The prevalence rate of Salmonella was found to be 37.5% (n=9/24 in cloacal swabs and 30.77% (n=8/26 in pharyngeal swabs with an overall prevalence rate of 34% (n=17/50. The prevalence rate of Salmonella pigeon varied slightly among locations; 34.62% (n=9/26 in live bird markets, and 33.33% (n=8/24 in villages. Molecular detection of 17 Salmonella isolates obtained from biochemical test was performed by genus specific PCR, where all of them amplified a region of 496-bp segment of the histidine transport operon gene. Antibiogram study revealed multi-drug resistant traits in most of the isolates tested. The highest resistance was found against Ampicillin (88.23% followed by Cephalexin (82.35%. The rate of sensitivity of the isolates to Ciprofloxacin was 100% followed by Azithromycin (82.35%, Gentamicin (76.47% and Nalidixic acid (76.47%. Conclusion: Our findings suggest that pigeons carry multi-drug resistant Salmonella that may transfer to the humans and animals. [J Adv Vet Anim Res 2016; 3(1.000: 51-55

  7. Increased colon cancer risk after severe Salmonella infection

    OpenAIRE

    Mughini-Gras, Lapo; Schaapveld, Michael; Kramers, Jolanda; Mooij, Sofie; Neefjes-Borst, E. Andra; van Pelt, Wilfrid; Neefjes, Jacques

    2018-01-01

    Background Colon cancer constitutes one of the most frequent malignancies. Previous studies showed that Salmonella manipulates host cell signaling pathways and that Salmonella Typhimurium infection facilitates colon cancer development in genetically predisposed mice. This epidemiological study examined whether severe Salmonella infection, usually acquired from contaminated food, is associated with increased colon cancer risk in humans. Methods and findings We performed a nationwide registry-b...

  8. Ludwig′s angina by Salmonella Typhi: A clinical dilemma

    Directory of Open Access Journals (Sweden)

    R K Mahajan

    2015-01-01

    Full Text Available Salmonella Typhi has rarely been associated with focal abscesses; and in literature, there is no evidence of its association with abscesses in the neck spaces. Ability of Salmonella Typhi to invade and localise in the neck spaces not only poses a diagnostic challenge but also underscores the necessity to understand the mechanisms that facilitate Salmonella Typhi to establish infections at sites completely non-traditional to the organism.

  9. Prevalence and antibiotic resistance of Salmonella Enteritidis and Salmonella Typhimurium in raw chicken meat at retail markets in Malaysia.

    Science.gov (United States)

    Thung, T Y; Mahyudin, N A; Basri, D F; Wan Mohamed Radzi, C W J; Nakaguchi, Y; Nishibuchi, M; Radu, S

    2016-08-01

    Salmonellosis is one of the major food-borne diseases in many countries. This study was carried out to determine the occurrence of Salmonella spp., Salmonella Enteritidis, and Salmonella Typhimurium in raw chicken meat from wet markets and hypermarkets in Selangor, as well as to determine the antibiotic susceptibility profile of S. Enteritidis and S. Typhimurium. The most probable number (MPN) in combination with multiplex polymerase chain reaction (mPCR) method was used to quantify the Salmonella spp., S. Enteritidis, and S. Typhimurium in the samples. The occurrence of Salmonella spp., S. Enteritidis, and S. Typhimurium in 120 chicken meat samples were 20.80%, 6.70%, and 2.50%, respectively with estimated quantity varying from retail chicken meat could be a source of multiple antimicrobial-resistance Salmonella and may constitute a public health concern in Malaysia. © 2016 Poultry Science Association Inc.

  10. Prediction of Salmonella carcass contamination by a comparative quantitative analysis of E. coli and Salmonella during pig slaughter

    DEFF Research Database (Denmark)

    Nauta, Maarten; Barfod, Kristen; Hald, Tine

    2013-01-01

    Salmonella concentrations. It is concluded that the faecal carriage of Salmonella together with the faecal contamination of carcasses, as predicted from E. coli data in the animal faeces and hygiene performance of the slaughterhouse, is not sufficient to explain carcass contamination with Salmonella. Our...... extensive data set showed that other factors than the observed faecal carriage of Salmonella by the individual animals brought to slaughter, play a more important role in the Salmonella carcass contamination of pork.......Faecal contamination of carcasses in the slaughterhouse is generally considered to be the source of Salmonella on pork. In this study the hygiene indicator Escherichia coli is used to quantify faecal contamination of carcasses and it is hypothesized that it can be used to predict the quantitative...

  11. Pathogenicity, Epidemiology and Virulence Factors of Salmonella species: A Review

    Directory of Open Access Journals (Sweden)

    Tamègnon Victorien DOUGNON

    2017-12-01

    Full Text Available Salmonella infections are major public health problems worldwide. The hereby review aimed to establish an overview on the pathogenicity, epidemiology and virulence factors of Salmonella spp. in the world. A systematic search was conducted online using the keywords ‘Salmonella’, ‘Salmonella spp.’, ‘Salmonella spp. Epidemiology’, ‘virulence factors of Salmonella spp. in the world’, ‘bacteria responsible for the contamination of meat products’, ‘non-typhoid salmonella’. These keywords were entered into databases such as PubMed and Google Scholar using mainly French language. The obtained articles were included based on the reliability of their source, the study area (usually Benin and Africa and the subject. The review revealed that Salmonella spp. is motile Gram-negative rod-shaped bacteria, of the family Enterobacteriaceae, currently counting more than 2,600 serovars. Human contamination occurs through the ingestion of contaminated water and food and can cause gastroenteritis or typhoid fever, which are two serious public health problems. A gene set constituting the pathogenicity islands determines the pathogenesis of Salmonella spp. The diagnosis is based on bacteriological, serological and molecular techniques. Salmonella infections are usually treated using antibiotics; however, emergence of antibiotic resistance in these microorganisms suggests that the anti-salmonella control should explore new sources such as medicinal plants

  12. Salmonella serotype distribution in the Dutch broiler supply chain.

    Science.gov (United States)

    van Asselt, E D; Thissen, J T N M; van der Fels-Klerx, H J

    2009-12-01

    Salmonella serotype distribution can give insight in contamination routes and persistence along a production chain. Therefore, it is important to determine not only Salmonella prevalence but also to specify the serotypes involved at the different stages of the supply chain. For this purpose, data from a national monitoring program in the Netherlands were used to estimate the serotype distribution and to determine whether this distribution differs for the available sampling points in the broiler supply chain. Data covered the period from 2002 to 2005, all slaughterhouses (n = 22), and the following 6 sampling points: departure from hatchery, arrival at the farm, departure from the farm, arrival at the slaughterhouse, departure from the slaughterhouse, and end of processing. Furthermore, retail data for 2005 were used for comparison with slaughterhouse data. The following serotypes were followed throughout the chain: Salmonella Enteritidis, Salmonella Typhimurium, Salmonella Paratyphi B var. Java (Salmonella Java), Salmonella Infantis, Salmonella Virchow, and Salmonella Mbandaka. Results showed that serotype distribution varied significantly throughout the supply chain (P supply chain up to the retail phase.

  13. Salmonella enterica Induces And Subverts The Plant Immune System

    Directory of Open Access Journals (Sweden)

    Ana Victoria Garcia

    2014-04-01

    Full Text Available Infections with Salmonella enterica belong to the most prominent causes of food poisoning and infected fruits and vegetables represent important vectors for salmonellosis. Whereas it was shown that plants raise defense responses against Salmonella, these bacteria persist and proliferate in various plant tissues. Recent reports shed light into the molecular interaction between plants and Salmonella, highlighting the defense pathways induced and the means used by the bacteria to escape the plant immune system and accomplish colonization. It was recently shown that plants detect Salmonella pathogen-associated molecular patterns (PAMPs, such as the flagellin peptide flg22, and activate hallmarks of the defense program known as PAMP-triggered immunity (PTI. Interestingly, certain Salmonella strains carry mutations in the flg22 domain triggering PTI, suggesting that a strategy of Salmonella is to escape plant detection by mutating PAMP motifs. Another strategy may rely on the type III secretion system (T3SS as T3SS mutants were found to induce stronger plant defense responses than wild type bacteria. Although Salmonella effector delivery into plant cells has not been shown, expression of Salmonella effectors in plant tissues shows that these bacteria also possess powerful means to manipulate the plant immune system. Altogether, the data gathered suggest that Salmonella triggers PTI in plants and evolved strategies to avoid or subvert plant immunity.

  14. Parotid abscess due to salmonella enteritidis: A case report.

    Science.gov (United States)

    Reyes, Cesar V; Jensen, JoAnne D

    2006-01-01

    Salmonella infection of the parotid gland is rare. An instance in a 50-year-old man of Salmonella enteritidis parotiditis initially recognized by microbial culture of a fine needle aspiration cytology material is described. The identified predisposing factor was chronic alcoholic abuse. For the infection source, a carrier state of salmonella parotitis was postulated, which progressed to focal abscess and was subsequently complicated by bacteremia and hematogenous spread to the liver, spleen and lungs. Salmonella should be included in the differential consideration of head and neck abscesses in immunocompromised individuals and treated aggressively.

  15. Prevalence of Salmonella spp. in oysters in the United States.

    Science.gov (United States)

    Brands, Danielle A; Inman, Allison E; Gerba, Charles P; Maré, C John; Billington, Stephen J; Saif, Linda A; Levine, Jay F; Joens, Lynn A

    2005-02-01

    Food-borne diseases such as salmonellosis can be attributed, in part, to the consumption of raw oysters. To determine the prevalence of Salmonella spp. in oysters, oysters harvested from 36 U.S. bays (12 each from the West, East, and Gulf coasts in the summer of 2002, and 12 bays, four per coast, in the winter of 2002-2003) were tested. Salmonella was isolated from oysters from each coast of the United States, and 7.4% of all oysters tested contained Salmonella. Isolation tended to be bay specific, with some bays having a high prevalence of Salmonella, while other bays had none. Differences in the percentage of oysters from which Salmonella was isolated were observed between the summer and winter months, with winter numbers much lower probably due to a variety of weather-related events. The vast majority (78/101) of Salmonella isolates from oysters were Salmonella enterica serovar Newport, a major human pathogen, confirming the human health hazard of raw oyster consumption. Contrary to previous findings, no relationship was found between the isolation of fecal coliforms and Salmonella from oysters, indicating a necessity for specific monitoring for Salmonella and other pathogens rather than the current reliance on fecal coliform testing.

  16. Salmonella enterica induces and subverts the plant immune system

    KAUST Repository

    García, Ana V.

    2014-04-04

    Infections with Salmonella enterica belong to the most prominent causes of food poisoning and infected fruits and vegetables represent important vectors for salmonellosis. Although it was shown that plants raise defense responses against Salmonella, these bacteria persist and proliferate in various plant tissues. Recent reports shed light into the molecular interaction between plants and Salmonella, highlighting the defense pathways induced and the means used by the bacteria to escape the plant immune system and accomplish colonization. It was recently shown that plants detect Salmonella pathogen-associated molecular patterns (PAMPs), such as the flagellin peptide flg22, and activate hallmarks of the defense program known as PAMP-triggered immunity (PTI). Interestingly, certain Salmonella strains carry mutations in the flg22 domain triggering PTI, suggesting that a strategy of Salmonella is to escape plant detection by mutating PAMP motifs. Another strategy may rely on the type III secretion system (T3SS) as T3SS mutants were found to induce stronger plant defense responses than wild type bacteria. Although Salmonella effector delivery into plant cells has not been shown, expression of Salmonella effectors in plant tissues shows that these bacteria also possess powerful means to manipulate the plant immune system. Altogether, these data suggest that Salmonella triggers PTI in plants and evolved strategies to avoid or subvert plant immunity. 2014 Garca and Hirt.

  17. Salmonella in Wastes Produced at Commercial Poultry Farms1

    Science.gov (United States)

    Kraft, D. J.; Olechowski-Gerhardt, Carolyn; Berkowitz, J.; Finstein, M. S.

    1969-01-01

    Composite samples of freshly voided excreta from 91 poultry houses were tested qualitatively for Salmonella; 26 (29%) were positive. The houses were located on 36 farms, 18 of which (50%) yielded one or more positive samples. In a separate, quantitative study, Salmonella densities ranged from less than 1 to over 34,000 per g of excreta (dry weight). High densities were noted in waste from cage houses, but not in waste from floor houses (litter or wire floors). Salmonella-shedding chickens were located in only one small area of the row of cages examined in detail. A total of 15 Salmonella serotypes were identified during the study. PMID:5370457

  18. Salmonella in wastes produced at commercial poultry farms.

    Science.gov (United States)

    Kraft, D J; Olechowski-Gerhardt, C; Berkowitz, J; Finstein, M S

    1969-11-01

    Composite samples of freshly voided excreta from 91 poultry houses were tested qualitatively for Salmonella; 26 (29%) were positive. The houses were located on 36 farms, 18 of which (50%) yielded one or more positive samples. In a separate, quantitative study, Salmonella densities ranged from less than 1 to over 34,000 per g of excreta (dry weight). High densities were noted in waste from cage houses, but not in waste from floor houses (litter or wire floors). Salmonella-shedding chickens were located in only one small area of the row of cages examined in detail. A total of 15 Salmonella serotypes were identified during the study.

  19. Salmonella outbreak among railway and airline passengers.

    Science.gov (United States)

    Hatakka, M

    1992-01-01

    A widespread outbreak by Salmonella infantis, infecting a total of 226 people, occurred in Finland at the beginning of August 1986. Of those infected, 107 were railway passengers, 91 were airline passengers and 28 were employed in a food processing establishment. The outbreak among the railway passengers was caused by egg sandwiches, the airline passengers were infected by a meal served on board and the catering employees by the breakfast served in the establishment. The outbreak was caused by food prepared in the establishment's kitchen. The employees' breakfasts had probably been contaminated by an employee who was a symptom-free Salmonella infantis carrier, and a number of the employees subsequently became infected, leading to widespread contamination of the food prepared in the establishment. The spread of the outbreak was further influenced by a heatwave at the time and by shortcomings in the cold storage facilities. The kitchen's hygiene supervision and the quality control of its output were reorganized after the outbreak.

  20. Whole Genome Epidemiological Typing of Salmonella

    DEFF Research Database (Denmark)

    Leekitcharoenphon, Pimlapas

    available Salmonella enterica genomes (accessed in April 2011). A consensus tree based on variation of the core genes gives better resolution than 16S rRNA and MLST that rarely provide separation between closely related strains. The performance of the pan-genome tree which is based on the presence....../absence of all genes across genomes, is similar to the consensus tree but with higher branching confidence value. The core genes can be divided into two categories: a few highly variable genes and a larger set of conserved core genes, with low variance. These core genes are useful for investigating molecular...... evolution and remain useful as candidate genes for bacterial genome typing-even if they cannot be expected to differentiate highly clonal isolates e.g. outbreak cases of Salmonella [I]. To achieve successful ‘real-time’ monitoring and identification of outbreaks, rapid and reliable sub-typing is essential...

  1. Salmonella Dublin kan give store tab

    DEFF Research Database (Denmark)

    Nielsen, Torben Dahl; Nielsen, Liza Rosenbaum; Kudahl, Anne Margrethe Braad

    2012-01-01

    Store besætninger lider størst økonomisk tab ved infektion med Salmonella Dublin. Selv i en veldrevet besætning kan tabet løbe op i mellem 1,3 og 3,3 millioner kr. over en tiårs periode. Ved uhensigtsmæssige hygiejne- og managementrutiner kan tabet nemt blive meget højere.......Store besætninger lider størst økonomisk tab ved infektion med Salmonella Dublin. Selv i en veldrevet besætning kan tabet løbe op i mellem 1,3 og 3,3 millioner kr. over en tiårs periode. Ved uhensigtsmæssige hygiejne- og managementrutiner kan tabet nemt blive meget højere....

  2. Psoralen photomutagenic specificity in Salmonella typhimurium

    International Nuclear Information System (INIS)

    Koch, W.H.

    1986-01-01

    The cytotoxic and mutagenic specificity of two therapeutically employed psoralens was examined in several Ames Salmonella typhimurium strains with near ultraviolet light activation. Photomutagenic activity of 8-methoxypsoralen (8MOP) and 4,5',8-trimethylpsoralen (TMP) was found to be sequence-specific, and additionally was dependent on the level of DNA-repair proficiency. Phototoxicity was essentially identical in hisC3076, hisD3052 and hisG46 strains; uvrB - excision-repair-deficient bacteria were considerably more susceptible to lethal effects than wild-type parental strains. Finally, the data show that psoralens are potent frameshift photomutagens in Salmonella hisC3076 strains and demonstrate the potential utility of these strains in evaluating photomutagenic and phototoxic activity of new furocoumarin derivatives. (Auth.)

  3. Organoid and Enteroid Modeling of Salmonella Infection

    Directory of Open Access Journals (Sweden)

    Yuebang Yin

    2018-04-01

    Full Text Available Salmonella are Gram-negative rod-shaped facultative anaerobic bacteria that are comprised of over 2,000 serovars. They cause gastroenteritis (salmonellosis with headache, abdominal pain and diarrhea clinical symptoms. Salmonellosis brings a heavy burden for the public health in both developing and developed countries. Antibiotics are usually effective in treating the infected patients with severe gastroenteritis, although antibiotic resistance is on the rise. Understanding the molecular mechanisms of Salmonella infection is vital to combat the disease. In vitro immortalized 2-D cell lines, ex vivo tissues/organs and several animal models have been successfully utilized to study Salmonella infections. Although these infection models have contributed to uncovering the molecular virulence mechanisms, some intrinsic shortcomings have limited their wider applications. Notably, cell lines only contain a single cell type, which cannot reproduce some of the hallmarks of natural infections. While ex vivo tissues/organs alleviate some of these concerns, they are more difficult to maintain, in particular for long term experiments. In addition, non-human animal models are known to reflect only part of the human disease process. Enteroids and induced intestinal organoids are emerging as effective infection models due to their closeness in mimicking the infected tissues/organs. Induced intestinal organoids are derived from iPSCs and contain mesenchymal cells whereas enteroids are derive from intestinal stem cells and are comprised of epithelial cells only. Both enteroids and induced intestinal organoids mimic the villus and crypt domains comparable to the architectures of the in vivo intestine. We review here that enteroids and induced intestinal organoids are emerging as desired infection models to study bacterial-host interactions of Salmonella.

  4. Salmonella serotypes and their antimicrobial susceptibility in apparently healthy dogs in Addis Ababa, Ethiopia.

    Science.gov (United States)

    Kiflu, Bitsu; Alemayehu, Haile; Abdurahaman, Mukarim; Negash, Yohannes; Eguale, Tadesse

    2017-05-19

    The close bond between pet animals and family members poses risk of infection with zoonotic bacterial pathogens such as Salmonella. No data is available on occurrence of Salmonella in dogs in Ethiopia. The aim of this study was therefore to determine the prevalence, serotype distribution and antimicrobial resistance of Salmonella from feces of apparently healthy dogs in Addis Ababa, Ethiopia. Of the total 360 dogs examined, 42 (11.7%; 95% Confidence limit of 8.5%-15.4%) were positive for Salmonella. Fourteen serotypes were detected and the predominant ones were S. Bronx (n = 7; 16.7%), S. Newport (n = 6; 14.3%), followed by S. Typhimurium, S. Indiana, S. Kentucky, S. Saintpaul and S. Virchow (n = 4; 9.5%) each. Salmonella infection status was significantly associated with history of symptom of diarrhea during the past 60 days (OR = 3.78; CI = 1.76-8.13; p = 0). Highest resistance rates were found for oxytetracycline (59.5%), neomycin (50%), streptomycin (38.1%), cephalothin (33.3%), doxycycline (30.9%), ampicillin (30.9%) and amoxicillin + clavulanic acid (26.2%). Thirty eight (90.5%) of the isolates were resistant or intermediately resistant to at least one of the 16 antimicrobials tested. Resistance to two or more antimicrobials was detected in 30 (71.4%) of the isolates. Resistance to three or more antimicrobials was detected in 19 (45.2%) of the isolates. This study demonstrated high carriage rate of Salmonella serotypes known for causing human salmonellosis and large proportion of them were resistant to antimicrobials used in public and veterinary medicine for management of various bacterial infections, suggesting the possible risk of infection of human population in close contact with these dogs by drug resistant pathogens. Therefore, it is vital to work on raising public awareness on zoonotic canine diseases prevention measures and good hygienic practices.

  5. Microbiological quality and antimicrobial resistance characterization of Salmonella spp. in fresh milk value chains in Ghana.

    Science.gov (United States)

    Parry-Hanson Kunadu, Angela; Holmes, Mark; Miller, Eric L; Grant, Andrew J

    2018-07-20

    Consumer perception of poor hygiene of fresh milk products is a major barrier to promotion of milk consumption as an intervention to alleviate the burden of malnutrition in Ghana. Fresh milk is retailed raw, boiled, or processed into unfermented cheese and spontaneously fermented products in unlicensed outlets. In this study, we have determined microbiological quality of informally retailed fresh milk products and characterized the genomic diversity and antimicrobial resistance (AMR) patterns of non-typhoidal Salmonella (NTS) in implicated products. A total of 159 common dairy products were purchased from five traditional milk markets in Accra. Samples were analysed for concentrations of aerobic bacteria, total and fecal coliforms, Escherichia coli, staphylococci, lactic acid bacteria and yeast and moulds. The presence of Salmonella, E. coli O157:H7, Listeria monocytogenes and Staphylococcus aureus were determined. AMR of Salmonella against 18 antibiotics was experimentally determined. Genome sequencing of 19 Salmonella isolates allowed determination of serovars, antigenic profiles, prediction of AMR genes in silico and inference of phylogenetic relatedness between strains. Raw and heat-treated milk did not differ significantly in overall bacterial quality (P = 0.851). E. coli O157:H7 and Staphylococcus aureus were present in 34.3% and 12.9% of dairy products respectively. Multidrug resistant (MDR) Salmonella enterica serovars Muenster and Legon were identified in 11.8% and 5.9% of unfermented cheese samples respectively. Pan genome analysis revealed a total of 3712 core genes. All Salmonella strains were resistant to Trimethoprim/Sulfamethoxazole, Cefoxitin, Cefuroxime Axetil and Cefuroxime. Resistance to Chloramphenicol (18%) and Ciprofloxacin (100%), which are first line antibiotics used in treatment of NTS bacteremia in Ghana, was evident. AMR was attributed to presence and/or mutations in the following genes: golS, sdiA for cephalosporins, aac(6')-Iy, ant

  6. Survival and transmission of Salmonella enterica serovar typhimurium in an outdoor organic pig farming environment

    DEFF Research Database (Denmark)

    Jensen, Annette Nygaard; Dalsgaard, Anders; Stockmarr, Anders

    2006-01-01

    It was investigated how organic rearing conditions influence the Salmonella enterica infection dynamics in pigs and whether Salmonella persists in the paddock environment. Pigs inoculated with S. enterica serovar Typhimurium were grouped with Salmonella-negative tracer pigs. Bacteriological...... the seroprevalence. Salmonella persisted in the paddock environment, as Salmonella was isolated from 46% of soil and water samples (n = 294). After removal of pigs, Salmonella was found in soil samples for up to. 5 weeks and in shelter huts during the entire test period (7 weeks). Subsequent introduction...... of Salmonella-negative pigs into four naturally Salmonella-contaminated paddocks caused Salmonella infections of pigs in two paddocks. In one of these paddocks, all tracer pigs (n = 10) became infected, coinciding with a previous high Salmonella infection rate and high Salmonella excretion level. Our results...

  7. Highly efficient residue-selective labeling with isotope-labeled Ile, Leu, and Val using a new auxotrophic E. coli strain

    International Nuclear Information System (INIS)

    Miyanoiri, Yohei; Ishida, Yojiro; Takeda, Mitsuhiro; Terauchi, Tsutomu; Inouye, Masayori; Kainosho, Masatsune

    2016-01-01

    We recently developed a practical protocol for preparing proteins bearing stereo-selectively 13 C-methyl labeled leucines and valines, instead of the commonly used 13 C-methyl labeled precursors for these amino acids, by E. coli cellular expression. Using this protocol, proteins with any combinations of isotope-labeled or unlabeled Leu and Val residues were prepared, including some that could not be prepared by the precursor methods. However, there is still room for improvement in the labeling efficiencies for Val residues, using the methods with labeled precursors or Val itself. This is due to the fact that the biosynthesis of Val could not be sufficiently suppressed, even by the addition of large amounts of Val or its precursors. In this study, we completely solved this problem by using a mutant strain derived from E. coli BL21(DE3), in which the metabolic pathways depending on two enzymes, dihydroxy acid dehydratase and β-isopropylmalate dehydrogenase, are completely aborted by deleting the ilvD and leuB genes, which respectively encode these enzymes. The ΔilvD E. coli mutant terminates the conversion from α,β-dihydroxyisovalerate to α-ketoisovalerate, and the conversion from α,β-dihydroxy-α-methylvalerate to α-keto-β-methylvalerate, which produce the preceding precursors for Val and Ile, respectively. By the further deletion of the leuB gene, the conversion from Val to Leu was also fully terminated. Taking advantage of the double-deletion mutant, ΔilvDΔleuB E. coli BL21(DE3), an efficient and residue-selective labeling method with various isotope-labeled Ile, Leu, and Val residues was established.

  8. Highly efficient residue-selective labeling with isotope-labeled Ile, Leu, and Val using a new auxotrophic E. coli strain

    Energy Technology Data Exchange (ETDEWEB)

    Miyanoiri, Yohei [Nagoya University, Structural Biology Research Center, Graduate School of Science (Japan); Ishida, Yojiro [Rutgers University-Robert Wood Johnson Medical School, Center for Advanced Biotechnology and Medicine (United States); Takeda, Mitsuhiro [Nagoya University, Structural Biology Research Center, Graduate School of Science (Japan); Terauchi, Tsutomu [Tokyo Metropolitan University, Graduate School of Science and Engineering (Japan); Inouye, Masayori [Rutgers University-Robert Wood Johnson Medical School, Center for Advanced Biotechnology and Medicine (United States); Kainosho, Masatsune, E-mail: kainosho@tmu.ac.jp [Nagoya University, Structural Biology Research Center, Graduate School of Science (Japan)

    2016-06-15

    We recently developed a practical protocol for preparing proteins bearing stereo-selectively {sup 13}C-methyl labeled leucines and valines, instead of the commonly used {sup 13}C-methyl labeled precursors for these amino acids, by E. coli cellular expression. Using this protocol, proteins with any combinations of isotope-labeled or unlabeled Leu and Val residues were prepared, including some that could not be prepared by the precursor methods. However, there is still room for improvement in the labeling efficiencies for Val residues, using the methods with labeled precursors or Val itself. This is due to the fact that the biosynthesis of Val could not be sufficiently suppressed, even by the addition of large amounts of Val or its precursors. In this study, we completely solved this problem by using a mutant strain derived from E. coli BL21(DE3), in which the metabolic pathways depending on two enzymes, dihydroxy acid dehydratase and β-isopropylmalate dehydrogenase, are completely aborted by deleting the ilvD and leuB genes, which respectively encode these enzymes. The ΔilvD E. coli mutant terminates the conversion from α,β-dihydroxyisovalerate to α-ketoisovalerate, and the conversion from α,β-dihydroxy-α-methylvalerate to α-keto-β-methylvalerate, which produce the preceding precursors for Val and Ile, respectively. By the further deletion of the leuB gene, the conversion from Val to Leu was also fully terminated. Taking advantage of the double-deletion mutant, ΔilvDΔleuB E. coli BL21(DE3), an efficient and residue-selective labeling method with various isotope-labeled Ile, Leu, and Val residues was established.

  9. Quinolone Resistance among Salmonella enterica from Cattle, Broilers and Swine in Denmark

    DEFF Research Database (Denmark)

    Wiuff, C.; Baggesen, Dorte Lau; Madsen, M.

    2000-01-01

    This study was conducted to determine the susceptibility to nalidixic acid and fluoroquinolones of Salmonella Dublin, S. Enteritidis, and S. Typhimurium isolates from cattle, broilers, and pigs over time in Denmark and to characterise the gyrA, gyrB, and parC genes in quinolone-resistant isolates...... that quinolone-resistant isolates have emerged in recent years among food-producing animals, especially among S. Enteritidis from broilers in Denmark, and that the resistance mainly is associated with mutations in gyrA.......This study was conducted to determine the susceptibility to nalidixic acid and fluoroquinolones of Salmonella Dublin, S. Enteritidis, and S. Typhimurium isolates from cattle, broilers, and pigs over time in Denmark and to characterise the gyrA, gyrB, and parC genes in quinolone-resistant isolates...... to quinolones. A single (1.1%) S. Typhimurium isolate from 1995 and three (5.9%) from 1998 were resistant to nalidixic acid. Six (9.0%) S. Dublin isolates from 1996, four (4.2%) from 1997, and one (1.7%) from 1998 were resistant to nalidixic acid. Resistance was not observed among isolates from cattle in 1999...

  10. Stable Isotope Labeling by Amino Acids in Cell Culture (SILAC) Applied to Quantitative Proteomics of Bacillus subtilis

    DEFF Research Database (Denmark)

    Soufi, Boumediene; Kumar, C.; Gnad, F.

    2010-01-01

    We applied stable isotope labeling by amino acids in cell culture (SILAC) to large-scale quantitative proteomics analyses of the model bacterium Bacillus subtilis in two physiological conditions: growth on succinate and growth under phosphate starvation. Using a B. subtilis strain auxotrophic...... of the most comprehensive quantitative proteomics studies in bacteria, covering more than 75% of the B. subtilis genes expressed in the log phase of growth. Furthermore, we detect and quantify dynamics of 35 Ser/Thr/Tyr phosphorylation sites under growth on succinate, and 10 phosphorylation sites under...

  11. Study of Salmonella Typhimurium infection in laying hens

    Directory of Open Access Journals (Sweden)

    Kapil eChousalkar

    2016-02-01

    Full Text Available Members of Salmonella enterica are frequently involved in egg and egg product related human food poisoning outbreaks worldwide. In Australia, Salmonella Typhimurium is frequently involved in egg and egg product related foodborne illness and Salmonella Mbandaka has also been found to be a contaminant of the layer farm environment. The ability possessed by Salmonella Enteritidis to colonise reproductive organs and contaminate developing eggs has been well described. However, there are few studies investigating this ability for Salmonella Typhimurium. The hypothesis of this study was that the Salmonella Typhimurium can colonise the gut for a prolonged period of time and that horizontal infection through feces is the main route of egg contamination. At 14 weeks of age hens were orally infected with either S. Typhimurium PT 9 or S. Typhimurium PT 9 and Salmonella Mbandaka. Salmonella shedding in feces and eggs was monitored for 15 weeks post infection. Egg shell surface and internal contents of eggs laid by infected hens were cultured independently for detection of Salmonella spp. The mean Salmonella load in feces ranged from 1.54 to 63.35 and 0.31 to 98.38 most probable number/g (MPN/g in the S. Typhimurium and S. Typhimurium + S. Mbandaka group respectively. No correlation was found between mean fecal Salmonella load and frequency of egg shell contamination. Egg shell contamination was higher in S. Typhimurium + S. Mbandaka infected group (7.2% Typhimurium, 14.1% Mbandaka compared to birds infected with S. Typhimurium (5.66% however, co-infection had no significant impact on egg contamination by S. Typhimurium. Throughout the study Salmonella was not recovered from internal contents of eggs laid by hens. Salmonella was isolated from different segments of oviduct of hens from both the groups, however pathology was not observed on microscopic examination. This study investigated Salmonella shedding for up to 15 weeks p.i which is a longer period of

  12. Cross contamination of turkey carcasses by Salmonella species during defeathering.

    Science.gov (United States)

    Nde, C W; McEvoy, J M; Sherwood, J S; Logue, C M

    2007-01-01

    Salmonella present on the feathers of live birds could be a source of contamination to carcass skin during defeathering. In this study, the possibility of transfer of Salmonella from the feathers of live turkeys to carcass tissue during the defeathering process at a commercial turkey processing plant was investigated. The contribution of scald water and the fingers of the picker machines to cross contamination were also examined. Over 4 visits, swab samples were collected from 174 randomly selected tagged birds before and after defeathering. Two swab samples from the fingers of the picker machines and a sample of scald water were also collected during each visit. Detection of Salmonella was carried out following standard cultural and identification methods. The DNA fingerprints obtained from pulsed field gel electrophoresis of Salmonella serotypes isolated before and after defeathering, from scald water, and from the fingers of the picker machines were compared to trace cross contamination routes. Salmonella prevalence was similar before and after defeathering during visits 2 and 3 and significantly increased after defeathering during visits 1 and 4. Over the 4 visits, all Salmonella subtypes obtained after defeathering were also isolated before defeathering. The results of this study suggest that Salmonella was transferred from the feathers to carcass skin during each visit. On each visit, the Salmonella subtypes isolated from the fingers of the picker machines were similar to subtypes isolated before and after defeathering, indicating that the fingers facilitate carcass cross contamination during defeathering. Salmonella isolated from scald water during visit 4 was related to isolates obtained before and after defeathering, suggesting that scald water is also a vehicle for cross contamination during defeathering. By using molecular subtyping, this study demonstrated the relationship between Salmonella present on the feathers of live turkeys and carcass skin after

  13. Survival of Salmonella during baking of peanut butter cookies.

    Science.gov (United States)

    Lathrop, Amanda A; Taylor, Tiffany; Schnepf, James

    2014-04-01

    Peanuts and peanut-based products have been the source of recent Salmonella outbreaks worldwide. Because peanut butter is commonly used as an ingredient in baked goods, such as cookies, the potential risk of Salmonella remaining in these products after baking needs to be assessed. This research examines the potential hazard of Salmonella in peanut butter cookies when it is introduced via the peanut-derived ingredient. The survival of Salmonella during the baking of peanut butter cookies was determined. Commercial, creamy-style peanut butter was artificially inoculated with a five-strain Salmonella cocktail at a target concentration of 10(8) CFU/g. The inoculated peanut butter was then used to prepare peanut butter cookie dough following a standard recipe. Cookies were baked at 350 °F (177 °C) and were sampled after 10, 11, 12, 13, 14, and 15 min. Temperature profiles of the oven and cookies were monitored during baking. The water activity and pH of the inoculated and uninoculated peanut butter, raw dough, and baked cookies were measured. Immediately after baking, cookies were cooled, and the survival of Salmonella was determined by direct plating or enrichment. After baking cookies for 10 min, the minimum reduction of Salmonella observed was 4.8 log. In cookies baked for 13 and 14 min, Salmonella was only detectable by enrichment reflecting a Salmonella reduction in the range of 5.2 to 6.2 log. Cookies baked for 15 min had no detectable Salmonella. Results of this study showed that proper baking will reduce Salmonella in peanut butter cookies by 5 log or more.

  14. Diversity of Salmonella isolates from central Florida surface waters.

    Science.gov (United States)

    McEgan, Rachel; Chandler, Jeffrey C; Goodridge, Lawrence D; Danyluk, Michelle D

    2014-11-01

    Identification of Salmonella serotypes is important for understanding the environmental diversity of the genus Salmonella. This study evaluates the diversity of Salmonella isolates recovered from 165 of 202 Central Florida surface water samples and investigates whether the serotype of the environmental Salmonella isolates can be predicted by a previously published multiplex PCR assay (S. Kim, J. G. Frye, J. Hu, P. J. Fedorka-Cray, R. Gautom, and D. S. Boyle, J. Clin. Microbiol. 44:3608-3615, 2006, http://dx.doi.org/10.1128/JCM.00701-06). Multiplex PCR was performed on 562 Salmonella isolates (as many as 36 isolates per water sample) to predict serotypes. Kauffmann-White serogrouping was used to confirm multiplex PCR pattern groupings before isolates were serotyped, analyzed by pulsed-field gel electrophoresis, and assayed for antimicrobial susceptibility. In 41.2% of the Salmonella-positive water samples, all Salmonella isolates had identical multiplex PCR patterns; in the remaining 58.8%, two or more multiplex PCR patterns were identified. Within each sample, isolates with matching multiplex PCR patterns had matching serogroups. The multiplex patterns of 495 isolates (88.1%) did not match any previously reported pattern. The remaining 68 isolates matched reported patterns but did not match the serotypes for those patterns. The use of the multiplex PCR allowed the number of isolates requiring further analysis to be reduced to 223. Thirty-three Salmonella enterica serotypes were identified; the most frequent included serotypes Muenchen, Rubislaw, Anatum, Gaminara, and IV_50:z4,z23:-. A majority (141/223) of Salmonella isolates clustered into one genotypic group. Salmonella isolates in Central Florida surface waters are serotypically, genotypically, and phenotypically (in terms of antimicrobial susceptibility) diverse. While isolates could be grouped as different or potentially the same using multiplex PCR, the multiplex PCR pattern did not predict the Salmonella

  15. The SPR detection of Salmonella enteritidis in food using aptamers as recongnition elements

    Science.gov (United States)

    Di, W. T.; Du, X. W.; Pan, M. F.; Wang, J. P.

    2017-09-01

    In this experiment, a fast, accurate, non-destructive, unmarked and simple-operation detection method for Salmonella enteritidis in food was established by the BI-3000 plasma resonance biosensor (SPR). This article establishes a method of using nucleic acid aptamer as immune recognition element in SPR which can be employed to detect Salmonella enteritidis in food for the first time. The experimental conditions were screened and the experimental scheme was validated and applied. The best flow rate was 5μL/min, the best concentration of the aptamers was 180mM, and the best regenerating solution was the 20mM NaOH. This method had almost no cross-reactivity. Besides, we established a standard curve of Salmonella enteritidis and SPR signal, with the detection limit of 2 cfu/mL. Finally, we tested the samples of chicken, pork, shrimp and fish purchased from supermarkets. The method has the advantages of short time, low detection limit and easy operation, which can be used for a large number of food samples.

  16. A Real-Time PCR Detection of Genus Salmonella in Meat and Milk Samples

    Directory of Open Access Journals (Sweden)

    Jaroslav Pochop

    2013-05-01

    Full Text Available The aim of this study was follow the contamination of ready to eat milk and meat products with Salmonella spp. by using the Step One real-time PCR. Classical microbiological methods for detection of food-borne bacteria involve the use of pre-enrichment and/or specific enrichment, followed by the isolation of the bacteria in solid media and a final confirmation by biochemical and/or serological tests. We used the PrepSEQ Rapid Spin Sample Preparation Kit for isolation of DNA and SensiFAST SYBR Hi-ROX Kit for the real-time PCR performance. In the investigated samples without incubation we could detect strain of Salmonella sp. in five out of twenty three samples (swabs. This Step One real-time PCR assay is extremely useful for any laboratory in possession of a real-time PCR. It is a fast, reproducible, simple, specific and sensitive way to detect nucleic acids, which could be used in clinical diagnostic tests in the future. Our results indicated that the Step One real-time PCR assay developed in this study could sensitively detect Salmonella spp. in ready to eat food.

  17. Tackling the issue of environmental survival of live Salmonella Typhimurium vaccines: deletion of the lon gene.

    Science.gov (United States)

    Leyman, Bregje; Boyen, Filip; Van Parys, Alexander; Verbrugghe, Elin; Haesebrouck, Freddy; Pasmans, Frank

    2012-12-01

    Vaccination is an important measure to control Salmonella contamination in the meat production chain. A previous study showed that both the ΔrfaJ and ΔrfaL strains are suitable markers and allow serological differentiation of infected and vaccinated animals. The aim of this study was to verify whether deletion of the lon gene in a Salmonella Typhimurium ΔrfaJ marker strain resulted in decreased environmental survival. Our results indicate that deletion of the lon gene in the ΔrfaJ strain did not affect invasiveness in IPEC-J2 cells and resulted in an increased susceptibility to UV, disinfectants (such as hydrogen peroxide and tosylchloramide sodium) and citric acid. Immunization of pigs with inactivated ΔrfaJ or ΔlonΔrfaJ vaccines allowed differentiation of infected and vaccinated pigs. Furthermore, deletion of the lon gene did not reduce the protection conferred by live wild type or ΔrfaJ vaccines against subsequent challenge with a virulent Salmonella Typhimurium strain in BALB/c mice. Based on our results in mice, we conclude that deletion of lon in ΔrfaJ contributes to environmental safety of the ΔrfaJ DIVA strain. Copyright © 2012 Elsevier Ltd. All rights reserved.

  18. Antibiotic resistance determinants and genetic analysis of Salmonella enterica isolated from food in Morocco.

    Science.gov (United States)

    Murgia, Manuela; Bouchrif, Brahim; Timinouni, Mohammed; Al-Qahtani, Ahmed; Al-Ahdal, Mohammed N; Cappuccinelli, Pietro; Rubino, Salvatore; Paglietti, Bianca

    2015-12-23

    Antimicrobial-resistant non-typhoidal Salmonella (NTS) are an important cause of infection in Africa, but there is a lack of information on their molecular mechanisms of resistance and epidemiology. This study contributes to fill this gap through the characterization by pulsed-field gel electrophoresis (PFGE), multilocus sequence typing (MLST), plasmid profiling and analysis of antibiotic-resistance determinants of 94 Salmonella enterica strains isolated from food in Morocco. PFGE revealed considerable heterogeneity among the strains, showing 32 pulsotypes. MLST of strains representative of the different serovars evidenced 13 sequence types (STs), three of which were newly identified (ST1694, ST1768 and ST1818) and nine not previously reported in Morocco. Thirty-four strains harbored from one to four plasmids, of IncI1 group in S. Mbandaka, IncFIIA in S. Typhimurium, IncL/M in S. Hadar and S. Blockley. For the first time in Morocco an intact Salmonella Genomic Island 1 (SGI1) carrying the resistance genes aadA2, floR, tetG, blaPSE-1 and sul1 was detected in S. Typhimurium DT104. In serovar Hadar resistance to ampicillin, tetracycline and streptomycin was associated to blaTEM-1, tetA and strA genes respectively, whereas one mutation in gyrA (Asp87Asn) and one in parC (Thr54Ser) genes conferred resistance to nalidixic acid. These findings improve the information on foodborne Salmonella in Morocco, evidencing the presence of MDR strains potentially dangerous to humans, and provide useful data for future studies. Copyright © 2015 Elsevier B.V. All rights reserved.

  19. Antimicrobials for reduction of Salmonella contamination in uncooked, surface-browned breaded chicken products.

    Science.gov (United States)

    Moschonas, Galatios; Geornaras, Ifigenia; Stopforth, Jarret D; Wach, Damien; Woerner, Dale R; Belk, Keith E; Smith, Gary C; Sofos, John N

    2012-06-01

    Surface-browned but uncooked frozen breaded chicken products have been associated with salmonellosis outbreaks due to inadequate or no cooking of the products before consumption. This study was conducted to evaluate the effect of three antimicrobials against Salmonella during manufacture of a surface-browned, uncooked frozen breaded chicken meat product. Fresh chicken breast meat portions (5 by 5 by 5 cm) were inoculated (4 to 5 log CFU/g) with Salmonella and mixed with caprylic acid (CAA; 0.5 and 1.0%), carvacrol (CAR; 0.3 and 0.5%), ε-polylysine (POL; 0.125 and 0.25%), or distilled water (control). Sodium chloride (1.2%) and sodium tripolyphosphate (0.3%) were added to all treatments, and the mixtures were ground (5% total moisture enhancement level) and formed into portions (9 by 5 by 3 cm). The products were breaded and surface browned by baking in an oven (208°C for 15 min) or deep frying in vegetable oil (190°C for 15 s), packaged in polyethylene bags, and stored at -20°C for 7 days. Total reductions of inoculated Salmonella in untreated control oven- or fryer-browned products after frozen storage were 1.2 and 0.8 log CFU/g, respectively. In comparison, treatment with CAA, CAR, or POL reduced initial pathogen counts by 3.3 to >4.5, 4.1 to >4.7, and 1.1 to 1.6 log CFU/g, respectively, regardless of the antimicrobial concentration and browning method. Treatment with 1.0% CAA (oven browned) or 0.5% CAR (oven or fryer browned) reduced Salmonella to nondetectable levels (chicken products.

  20. Multiplex TaqMan® detection of pathogenic and multi-drug resistant Salmonella.

    Science.gov (United States)

    Singh, Prashant; Mustapha, Azlin

    2013-09-02

    Overuse of antibiotics in the medical and animal industries is one of the major causes for the development of multi-drug-resistant (MDR) food pathogens that are often difficult to treat. In the past few years, higher incidences of outbreaks caused by MDR Salmonella have been increasingly documented. The objective of this study was to develop a rapid multiplex real-time polymerase chain reaction (PCR) assay for simultaneous detection of pathogenic and MDR Salmonella spp. A multiplex TaqMan®real-time PCR was designed by targeting the invasin virulence gene (invA), and four commonly found antibiotic resistance genes, viz. ampicillin, chloramphenicol, streptomycin and tetracycline. To avoid false negative results and to increase the reliability of the assay, an internal amplification control (IAC) was added which was detected using a locked nucleic acid (LNA) probe. In serially diluted (5 ng-50 fg) DNA samples, the assay was able to detect 100 genomic equivalents of Salmonella, while in a multiplex format, the sensitivity was 1000 genomic equivalents. The assay performed equally well on artificially contaminated samples of beef trim, ground beef of different fat contents (73:27, 80:20, 85:15 and 93:7), chicken rinse, ground chicken, ground turkey, egg, spinach and tomato. While the detection limit for un-enriched inoculated food samples was 10(4) CFU/g, this was improved to 10 CFU/g after a 12-h enrichment in buffered peptone water, with 100% reproducibility. The multiplex real-time assay developed in this study can be used as a valuable tool to detect MDR virulent Salmonella, thus enhancing the safety of food. © 2013.

  1. Genetic characterisation of multidrug-resistant Salmonella enterica serotypes isolated from poultry in Cairo, Egypt

    Directory of Open Access Journals (Sweden)

    Mohammed Abdel-Maksoud

    2015-05-01

    Full Text Available Background: Food-borne diseases pose serious health problems, affecting public health and economic development worldwide. Methods: Salmonella was isolated from samples of chicken parts, skin samples of whole chicken carcasses, raw egg yolks, eggshells and chicken faeces. Resulting isolates were characterised by serogrouping, serotyping, antimicrobial susceptibility testing and detection of extended-spectrum β-lactamase (ESBL production. Antibiotic resistance genes and integrons were identified by polymerase chain reaction (PCR. Results: The detection rates of Salmonella were 60%, 64% and 62% in chicken parts, skin, and faeces, respectively, whereas the egg yolks and eggshells were uniformly negative. Salmonella Kentucky and S. Enteritidis serotypes comprised 43.6% and 2.6% of the isolates, respectively, whilst S. Typhimurium was absent. Variable resistance rates were observed against 16 antibiotics; 97% were resistant to sulfamethoxazole, 96% to nalidixic acid and tetracycline and 76% to ampicillin. Multidrug resistance was detected in 82% (64/78 of the isolates and ESBL production was detected in 8% (6/78. The β-lactamase blaTEM-1 gene was detected in 57.6% and blaSHV-1 in 6.8% of the isolates, whilst the blaOXA gene was absent. The sul1gene was detected in 97.3% and the sul2 gene in 5.3% of the isolates. Sixty-four of the 78 isolates (82% were positive for the integrase gene (int I from class 1 integrons, whilst int II was absent. Conclusion: This study reveals the presence of an alarming number of multidrug-resistant Salmonella isolates in the local poultry markets in Cairo. The high levels of drug resistance suggest an emerging problem that could impact negatively on efforts to prevent and treat poultry and poultry-transmitted human diseases in Egypt.

  2. Survival of Salmonella enterica in Freshwater and Sediments and Transmission by the Aquatic Midge Chironomus tentans (Chironomidae: Diptera)

    Science.gov (United States)

    Moore, Barry C.; Martinez, Edward; Gay, John M.; Rice, Daniel H.

    2003-01-01

    Survival of a nalidixic acid-resistant strain of Salmonella enterica serovar Typhimurium mr-DT-104 in water and sediments was tested using artificially contaminated aquaria. Water samples remained culture positive for salmonella for up to 54 days. Sediment samples were culture positive up to 119 days. In addition, potential mechanisms for spreading salmonella in the environments by chironomid larvae and adults were tested. We evaluated the acquisition of mr-DT-104 by chironomids from contaminated aquatic sediments and subsequent spread to uncontaminated sediments. Larval chironomids raised in contaminated sediments became culture positive, and the bacteria were carried over to adults after emergence. Contamination of clean sediments by chironomid larvae was not demonstrated. These findings clearly suggest that mr-DT-104 serovar organisms can survive in aquatic sediments for at least several months. Uptake of salmonellae by chironomid larvae and adults suggests that they are possible vectors of mr-DT-104 in both aquatic and terrestrial environments, although the role of larval defecation in movement of bacteria to new sediments was not demonstrated. PMID:12902242

  3. [The gentic principles for the design of live Salmonella vaccines].

    Science.gov (United States)

    Petrovskaia, V G; Marakusha, B I; Bondarenko, V M

    1996-01-01

    The presently known methods of obtaining Salmonella vaccine strains are characterized, their advantages and drawbacks are noted. Great importance of the genetic safety of Salmonella attenuated strains to be controlled is emphasized, taking into account that they are also used as carrier strains for obtaining hybrid and gene-engineering (vector) vaccines carrying immunogenicity factors of other species of pathogenic microorganisms.

  4. The occurrence and epidemiology of Salmonella in European pig slaughterhouses

    DEFF Research Database (Denmark)

    Hald, Tine; Wingstrand, Anne; Swanenburg, M.

    2003-01-01

    from 12 slaughterhouses in five European countries. Isolates were characterized by serotyping, phage typing and antimicrobial susceptibility. In one country, no Salmonella was found. Salmonella was isolated from 5.3% of 3485 samples of pork and from 13.8% of 3573 environmental samples from the seven...

  5. An atypical presentation of salmonella typhi - A case report

    Directory of Open Access Journals (Sweden)

    Jayakumar K

    2003-01-01

    Full Text Available Breast abscess due to Salmonella typhi is an extremely rare occurrence. A lady with a lump in the left breast was diagnosed to have a fibroadenoma and was subjected to a surgical procedure. She was found to have an abscess due to Salmonella typhi as confirmed by conventional bacteriological methods. She was treated with ciprofloxacin and responded favourably.

  6. Characterization of Salmonella enterica Ituri isolated from diseased ...

    African Journals Online (AJOL)

    User

    2013-04-17

    Apr 17, 2013 ... Salmonella enterica Ituri is an uncommon serotype associated with poultry disease. One of the serotype isolated from a poultry disease in Nigeria was characterized by serotyping and screening for the presence of Salmonella genomic island 1(SGI1) as a possible factor responsible for its involvement.

  7. Survival of Salmonella spp. In Waste Egg Wash Water

    Science.gov (United States)

    The survival of salmonellae under various environmental conditions has been subject of numerous research studies. Due to low densities of these organisms in natural samples, laboratory or clinical cultures were used to ensure that the initial density of salmonellae was sufficien...

  8. Using molecular techniques for rapid detection of Salmonella ...

    African Journals Online (AJOL)

    PRECIOUS

    2010-02-01

    Feb 1, 2010 ... A total of 152 samples of chicken and chicken products ... detection of Salmonella species in the collected field samples ... that 16 million new cases of typhoid fever occur each ... vative methods for the rapid identification of Salmonella ... saved for the PCR-Non Selective test (PCR-NS) and 1 ml of the.

  9. Prevalence of salmonella in captive reptiles from Croatia

    DEFF Research Database (Denmark)

    Lukac, Maja; Pedersen, Karl; Prukner-Radovcic, Estella

    2015-01-01

    from 200 apparently healthy reptiles were tested for Salmonella excretions by bacteriologic culture and serotyping. These 200 individual reptiles included 31 lizards, 79 chelonians, and 90 snakes belonging to private owners or housed at the Zagreb Zoo, Croatia. Salmonella was detected in a total of 13...

  10. Food contamination with salmonella and human health in Kinshasa ...

    African Journals Online (AJOL)

    SARAH

    2015-10-31

    Oct 31, 2015 ... Objectives: The objective of this study was to assess the level of salmonella contamination of fish and meat from public markets, meat from ... Material and sampling: Seventy-two samples of fresh fish, 120 samples of meat (beef, ..... prevalence and number of. Salmonella in sausages and their destruction.

  11. Nontyphoidal Salmonella: An Occupational Hazard for Clinical Laboratory Workers

    OpenAIRE

    Barker, Anna; Duster, Megan; Van Hoof, Sarah; Safdar, Nasia

    2015-01-01

    Laboratory-acquired infections due to nontyphoidal Salmonella are rare. Yet, recent outbreaks in microbiology teaching laboratories show that these species are still an appreciable occupational hazard for laboratory employees. This article presents two cases of nontyphoidal Salmonella that occurred at the authors' institution—an infected patient and a clinical laboratory worker who acquired the infection by handling this patient's specimens.

  12. Salmonella enterica induces and subverts the plant immune system

    KAUST Repository

    Garcí a, Ana V.; Hirt, Heribert

    2014-01-01

    ). Interestingly, certain Salmonella strains carry mutations in the flg22 domain triggering PTI, suggesting that a strategy of Salmonella is to escape plant detection by mutating PAMP motifs. Another strategy may rely on the type III secretion system (T3SS) as T3SS

  13. Detection and isolation of salmonella in broiler chickens around the ...

    African Journals Online (AJOL)

    Detection and isolation of salmonella in broiler chickens around the slaughter time. ES Soliman, E Taha, WS Abdella, MA Sobieh, PG Reddy. Abstract. Crop contents may serve as important sources of Salmonella carcass contamination within processing plants. This study, evaluated the effect of feed withdrawal before the ...

  14. Diagnosis of Salmonella Enteritidis Infection in Broiler Chickens ...

    African Journals Online (AJOL)

    Diagnosis of Salmonella Enteritidis Infection in Broiler Chickens Using Elisa. ES Soliman, E Taha, WS Abdella, C KilPatrick, AN Wise, MAA Sobieh, PG Reddy. Abstract. The program for the eradication of Salmonella Enteritidis from chickens was based on bacteriological examination of breeding flocks. There is a great need ...

  15. Isolation of Salmonella and Shigella species from house flies ...

    African Journals Online (AJOL)

    Salmonella and Shigella species were isolated from House flies (Musca domestica L.) from various sampling sites using selective media. Out of 34 pooled samples Shigella species were isolated in all (100%) of the samples while Salmonella species were isolated in 21 (61.7%) of the samples. The flies pooled from the ...

  16. Characterization of Salmonella enterica Ituri isolated from diseased ...

    African Journals Online (AJOL)

    Salmonella enterica Ituri is an uncommon serotype associated with poultry disease. One of the serotype isolated from a poultry disease in Nigeria was characterized by serotyping and screening for the presence of Salmonella genomic island 1(SGI1) as a possible factor responsible for its involvement in a poultry disease ...

  17. Effect of Carvacrol on Salmonella Saintpaul Biofilms on Stainless ...

    African Journals Online (AJOL)

    Purpose: To evaluate the effect of carvacrol against Salmonella Saintpaul biofilms on stainless steel surface. Methods: The effects of carvacrol on planktonic cells were evaluated by determining the minimum inhibitory concentration and minimal bactericidal concentration. The action of carvacrol on Salmonella Saintpaul ...

  18. Molecular and biochemical diagnosis of Salmonella in wastewater ...

    African Journals Online (AJOL)

    This study aimed to employ biochemical and molecular assays to detect and diagnose Salmonella in wastewater. For this reason, two water samples were collected from Alexandria wastewater treatment plant (S1) and septic tank of a hospital at Alexandria governorate (S2). Selective culture media specific for Salmonella ...

  19. Effects of challenge dose on faecal shedding of Salmonella ...

    African Journals Online (AJOL)

    Experimental infection of chickens with Salmonella enteritidis is often achieved by oral inoculation of live bacteria to caged chickens. Less information is available on influence of amount of Salmonella a chicken is exposed to during infection on the proportion that is eventually eliminated in faeces. This study evaluated the ...

  20. Prevalence of Salmonella on Sheep Carcasses Slaughtered at ...

    African Journals Online (AJOL)

    ... indicated that Salmonella is a common problem in slaughtered sheep carcasses in Adama municipal abattoir. Therefore, Sources of pathogens in food animals need to be investigated and a further study of pathogens in the food chain is recommended. Keywords: Adama Carcass Ethiopia Prevalence Salmonella Sheep.

  1. Multidrug resistant Salmonellae isolated from blood culture samples ...

    African Journals Online (AJOL)

    This study investigates the prevalence of R-plasmids in Salmonella sp. isolated from blood samples of suspected typhoid patients in Warri, Nigeria. A total of 136 blood samples were collected between May and December,2009 and screened for the presence of Salmonellae using standard blood culture techniques of which ...

  2. Serological prevalence and associated risk factors of Salmonella ...

    African Journals Online (AJOL)

    ... to identify risk factors associated with Salmonella infections in chickens. The overall sero-prevalence established using serum plate agglutination test was 16.7% (98/588). Using a univariate logistic analysis, factors significantly associated with Salmonella infections at p < 0.05 were presence of other birds in poultry farms ...

  3. Nontyphoidal Salmonella Septic arthritis of the elbow in a healthy ...

    African Journals Online (AJOL)

    A case of rarely encountered nontyphoidal Salmonella septic arthritis of the elbow in an infant with no preexisting disease is reported. Salmonella etiology was not suspected in this case, and the diagnosis was made only after bacterial isolation. Aspiration of the infected joint with radiological guidance initially failed to give a ...

  4. Antimicrobial Drug Resistance of Salmonella enterica Serovar Typhi in Asia and Molecular Mechanism of Reduced Susceptibility to the Fluoroquinolones▿

    OpenAIRE

    Chau, Tran Thuy; Campbell, James Ian; Galindo, Claudia M.; Van Minh Hoang, Nguyen; Diep, To Song; Nga, Tran Thu Thi; Van Vinh Chau, Nguyen; Tuan, Phung Quoc; Page, Anne Laure; Ochiai, R. Leon; Schultsz, Constance; Wain, John; Bhutta, Zulfiqar A.; Parry, Christopher M.; Bhattacharya, Sujit K.

    2007-01-01

    This study describes the pattern and extent of drug resistance in 1,774 strains of Salmonella enterica serovar Typhi isolated across Asia between 1993 and 2005 and characterizes the molecular mechanisms underlying the reduced susceptibilities to fluoroquinolones of these strains. For 1,393 serovar Typhi strains collected in southern Vietnam, the proportion of multidrug resistance has remained high since 1993 (50% in 2004) and there was a dramatic increase in nalidixic acid resistance between ...

  5. PCR-RFLP Analysis of a fliC Gene Fragment in Avian Salmonella Isolates

    Directory of Open Access Journals (Sweden)

    Zohreh Ebrahimvandi

    2014-07-01

    Full Text Available Background: Salmonella are a genus of zoonotic bacteria of worldwide economic and health importance. Members of Salmonella enterica subspecies enterica are mainly associated with warm-blooded vertebrates and are usually transmitted by ingestion of food or watercontaminated by infected feces. Objectives: The aim of this study was to apply a PCR-RFLP method based on the fliC gene to identify the serotypes of Salmonella isolates from Karaj, Iran. Materials and Methods: A total of 30 Salmonella isolates were serotyped by specific antisera. For the PCR-RFLP method based on the fliC gene, extracted DNA was used as the template for amplifying the fliC gene (1500 bp using specific primers. PCR products were subjected to digestion using HhaI restriction endonuclease. Results: This study determined 30 serotypes as Salmonella durban (56.6%, Salmonella uno (23.3%, Salmonella enteritidis (3.3%, Salmonella tinda (3.3%, Salmonella mjimweme (3.3%, Salmonella Thompson (3.3%, Salmonella sIIO8 (3.3 % and Salmonella sIIO7 (3.3%. Observations indicated that HhaI is able to discriminate Salmonella tinda and Salmonella thompson, yet Salmonella enteritidis, Salmonella durban and Salmonella mjimweme had the same pattern with this enzyme. Also Salmonella sIIO8, Salmonella sIIO7 and Salmonella uno showed the same pattern. Thus, regarding the size and the number of resulting fragments from this enzyme, four patterns were obtained for HhaI. Conclusion: A large number of Salmonella serotypes need to be analyzed by the PCR-RFLP method and different enzymes must be used to give reliable results.

  6. Effects of propolis from Brazil and Bulgaria on Salmonella serovars

    Directory of Open Access Journals (Sweden)

    R. O. Orsi

    2007-01-01

    Full Text Available Propolis shows biological properties such as antibacterial action. This bee product has a complex chemical composition, which depends on the local flora where it is produced. Salmonella serovars are responsible for human diseases that range from localized gastroenteritis to systemic infections. The aim of the present study was to investigate the susceptibility of Salmonella strains, isolated from food and infectious processes, to the antibacterial action of Brazilian and Bulgarian propolis, as well as to determine the behavior of these bacteria, according to the incubation period, in medium plus propolis. Dilution of ethanolic extract of propolis in agar was the used method. Brazilian and Bulgarian propolis showed an antibacterial action against all Salmonella serovars. The minimal inhibitory concentrations (MIC of propolis were similar, although they were collected in different geographic regions. Salmonella typhimurium, isolated from human infection, was more resistant to propolis than Salmonella enteritidis.

  7. Molecular Confirmation of Salmonella typhimuriumin Poultry from Kathmandu Valley

    Directory of Open Access Journals (Sweden)

    Sanjeev Kumar Adhikari

    2018-05-01

    Full Text Available A prevalence study was carried to isolate Salmonella typhimurium from blood (n= 50 and gut samples (n=100 of poultry in Kathmandu valley during early 2016. Salmonella typhimurium bacteria isolated in the selective media were biochemically confirmed based on Bergey’s Manual. Two sets of oligonucleotide primers-the genus specific 16S rRNA and the organism specific invA were employed for molecular level confirmation by the Polymerase Chain Reaction (PCR assay. The amplified fragments in 1% agarose gel observed at 406bp and 285bp, respectively confirmed the isolates to be Salmonella typhimurium. Of 150 samples tested, Salmonella typhimurium were isolated from 49 samples, among which nine were from blood (18% and forty from the gut (40%. The present result indicated an alarmingly high level of Salmonella typhimurium, which can result inzoonotic infection in humans owing to increased contact with poultry and consumption of poultry products in the Kathmandu valley.

  8. Evaluation of different analysis and identification methods for Salmonella detection in surface drinking water sources

    International Nuclear Information System (INIS)

    Hsu, Bing-Mu; Huang, Kuan-Hao; Huang, Shih-Wei; Tseng, Kuo-Chih; Su, Ming-Jen; Lin, Wei-Chen; Ji, Dar-Der; Shih, Feng-Cheng; Chen, Jyh-Larng; Kao, Po-Min

    2011-01-01

    The standard method for detecting Salmonella generally analyzes food or fecal samples. Salmonella often occur in relatively low concentrations in environmental waters. Therefore, some form of concentration and proliferation may be needed. This study compares three Salmonella analysis methods and develops a new Salmonella detection procedure for use in environmental water samples. The new procedure for Salmonella detection include water concentration, nutrient broth enrichment, selection of Salmonella containing broth by PCR, isolation of Salmonella strains by selective culture plates, detection of possible Salmonella isolate by PCR, and biochemical testing. Serological assay and pulsed-field gel electrophoresis (PFGE) can be used to identify Salmonella serotype and genotype, respectively. This study analyzed 116 raw water samples taken from 18 water plants and belonging to 5 watersheds. Of these 116, 10 water samples (8.6%) taken from 7 water plants and belonging to 4 watersheds were positive for a Salmonella-specific polymerase chain reaction targeting the invA gene. Guided by serological assay results, this study identified 7 cultured Salmonella isolates as Salmonella enterica serovar: Alnaby, Enteritidis, Houten, Montevideo, Newport, Paratyphi B var. Java, and Victoria. These seven Salmonella serovars were identified in clinical cases for the same geographical areas, but only one of them was 100% homologous with clinical cases in the PFGE pattern. - Research highlights: → A new Salmonella detecting procedure for environmental water is developed. → Salmonella isolates are identified by serological assay and PFGE. → A total of seven Salmonella serovars is isolated from environmental water.

  9. Evaluation of different analysis and identification methods for Salmonella detection in surface drinking water sources

    Energy Technology Data Exchange (ETDEWEB)

    Hsu, Bing-Mu, E-mail: bmhsu@ccu.edu.tw [Department of Earth and Environmental Sciences, National Chung Cheng University, Chiayi, Taiwan, ROC (China); Huang, Kuan-Hao; Huang, Shih-Wei [Department of Earth and Environmental Sciences, National Chung Cheng University, Chiayi, Taiwan, ROC (China); Tseng, Kuo-Chih [Department of Internal Medicine, Buddhist Dalin Tzu Chi General Hospital, Chiayi, Taiwan, ROC (China); Su, Ming-Jen [Department of Clinical Pathology, Buddhist Dalin Tzu Chi General Hospital, Chiayi, Taiwan, ROC (China); Lin, Wei-Chen; Ji, Dar-Der [Research and Diagnostic Center, Centers for Disease Control, Taipei, Taiwan, ROC (China); Shih, Feng-Cheng; Chen, Jyh-Larng [Department of Environmental Engineering and Health, Yuanpei University of Science and Technology, HsinChu, Taiwan, ROC (China); Kao, Po-Min [Department of Earth and Environmental Sciences, National Chung Cheng University, Chiayi, Taiwan, ROC (China)

    2011-09-15

    The standard method for detecting Salmonella generally analyzes food or fecal samples. Salmonella often occur in relatively low concentrations in environmental waters. Therefore, some form of concentration and proliferation may be needed. This study compares three Salmonella analysis methods and develops a new Salmonella detection procedure for use in environmental water samples. The new procedure for Salmonella detection include water concentration, nutrient broth enrichment, selection of Salmonella containing broth by PCR, isolation of Salmonella strains by selective culture plates, detection of possible Salmonella isolate by PCR, and biochemical testing. Serological assay and pulsed-field gel electrophoresis (PFGE) can be used to identify Salmonella serotype and genotype, respectively. This study analyzed 116 raw water samples taken from 18 water plants and belonging to 5 watersheds. Of these 116, 10 water samples (8.6%) taken from 7 water plants and belonging to 4 watersheds were positive for a Salmonella-specific polymerase chain reaction targeting the invA gene. Guided by serological assay results, this study identified 7 cultured Salmonella isolates as Salmonella enterica serovar: Alnaby, Enteritidis, Houten, Montevideo, Newport, Paratyphi B var. Java, and Victoria. These seven Salmonella serovars were identified in clinical cases for the same geographical areas, but only one of them was 100% homologous with clinical cases in the PFGE pattern. - Research highlights: {yields} A new Salmonella detecting procedure for environmental water is developed. {yields} Salmonella isolates are identified by serological assay and PFGE. {yields} A total of seven Salmonella serovars is isolated from environmental water.

  10. The eleventh CRL-Salmonella workshop, 9 May 2006, Saint Malo, France

    NARCIS (Netherlands)

    Mooijman KA; MGB

    2006-01-01

    De elfde workshop georganiseerd door het Communautair Referentie Laboratorium voor Salmonella (CRL-Salmonella) werd gehouden op 9 mei 2006 in Saint Malo, Frankrijk. Deelnemers waren vertegenwoordigers van de nationale Referentie Laboratoria voor Salmonella (NRLs-Salmonella) van de lidstaten van de

  11. A naturally occurring single nucleotide polymorphism in the Salmonella SPI-2 type III effector srfH/sseI controls early extraintestinal dissemination.

    Directory of Open Access Journals (Sweden)

    Joshua M Thornbrough

    Full Text Available CD18 expressing phagocytes associated with the gastro-intestinal (GI epithelium can shuttle Salmonella directly into the bloodstream within a few minutes following microbial ingestion. We have previously demonstrated that Salmonella controls the CD18 pathway to deeper tissue, manipulating the migratory properties of infected cells as an unappreciated component of its pathogenesis. We have observed that one type III effector, SrfH (also called SseI that Salmonella secretes into infected phagocytes manipulates the host protein TRIP6 to stimulate their migration. Paradoxically, SrfH was shown in another study to subvert a different host protein, IQGAP1, in a manner that inhibits the productive motility of such cells, perhaps to avoid interactions with T cells. Here, we resolve the discrepancy. We report that one naturally occurring allele of srfH promotes the migration of infected phagocytes into the bloodstream, while another naturally occurring allele that differs by only a single nucleotide polymorphism (SNP does not. This SNP determines if the protein contains an aspartic acid or a glycine residue at position 103 and may determine if SrfH binds TRIP6. SrfH Gly103 is a rare allele, but is present in the highly invasive strain Salmonella enterica serovar Typhimurium UK-1 (stands for universal killer. It is also present in the genome of the only sequenced strain belonging to the emerging pandemic Salmonella enterica serovar 4, [5],12,i:-, which is frequently associated with septicemia. Finally, we present evidence that suggests that Gifsy-2, the bacteriophage upon which srfH resides, is present in a clinical isolate of the human-specific pathogen, Salmonella enterica serovar Typhi. These observations may have interesting implications for our understanding of Salmonella pathogenesis.

  12. EURL-Salmonella 8th interlaboratory comparison study Food 2016 : Detection of Salmonella in minced chicken meat

    NARCIS (Netherlands)

    Kuijpers AFA; Mooijman KA; VDL; Z&O

    2018-01-01

    In 2016, it was shown that all 34 National Reference Laboratories (NRLs), 30 of which are located in the European Union, were able to detect high and low levels of Salmonella in minced chicken meat. Three NRLs reported Salmonella in one 'blank' minced meat sample. This was probably caused by the

  13. Antibiotic resistance, integrons and Salmonella genomic island 1 among non-typhoidal Salmonella serovars in The Netherlands.

    NARCIS (Netherlands)

    Vo, An T T; Duijkeren, Engeline van; Fluit, Ad C; Wannet, Wim J B; Verbruggen, Anjo J; Maas, Henny M E; Gaastra, Wim

    2006-01-01

    The objective of this study was to investigate the antimicrobial resistance patterns, integron characteristics and gene cassettes as well as the presence of Salmonella genomic island 1 (SGI1) in non-typhoidal Salmonella (NTS) isolates from human and animal origin. Epidemiologically unrelated Dutch

  14. Fate of Salmonella throughout Production and Refrigerated Storage of Tahini.

    Science.gov (United States)

    Zhang, Yangjunna; Keller, Susanne E; Grasso-Kelley, Elizabeth M

    2017-06-01

    Tahini, a low-moisture food that is made from sesame seeds, has been implicated in outbreaks of salmonellosis. In this study, the fate of Salmonella was determined through an entire process for the manufacture of tahini, including a 24-h seed soaking period before roasting, subsequent grinding, and storage at refrigeration temperature. Salmonella populations increased by more than 3 log CFU/g during a 24-h soaking period, reaching more than 7 log CFU/g. Survival of Salmonella during roasting at three temperatures, 95, 110, and 130°C, was assessed using seeds on which Salmonella was grown. Salmonella survival was impacted both by temperature and the water activity (a w ) at the beginning of the roasting period. When roasted at 130°C with a high initial a w (≥0.90) and starting Salmonella populations of ∼8.5 log CFU/g, populations quickly decreased below detection limits within the first 10 min. However, when the seeds were reduced to an a w of 0.45 before roasting at the same temperature, 3.5 log CFU/g remained on the seeds after 60 min. In subsequent storage studies, seeds were roasted at 130°C for 15 min before processing into tahini. For the storage studies, tahini was inoculated using two methods. The first method used seeds on which Salmonella was first grown before roasting. In the second method, Salmonella was inoculated into the tahini after manufacture. All tahini was stored for 119 days at 4°C. No change in Salmonella populations was recorded for tahini throughout the entire 119 days regardless of the inoculation method used. These combined results indicate the critical importance of a w during a roasting step during tahini manufacture. Salmonella that survive roasting will likely remain viable throughout the normal shelf life of tahini.

  15. Salmonella infection and carriage in reptiles in a zoological collection.

    Science.gov (United States)

    Clancy, Meredith M; Davis, Meghan; Valitutto, Marc T; Nelson, Kenrad; Sykes, John M

    2016-05-01

    OBJECTIVE To identify important subspecies and serovars of Salmonella enterica in a captive reptile population and clinically relevant risk factors for and signs of illness in Salmonella-positive reptiles. DESIGN Retrospective cross-sectional study. ANIMALS 11 crocodilians (4 samples), 78 snakes (91 samples), 59 lizards (57 samples), and 34 chelonians (23 samples) at the Bronx Zoo from 2000 through 2012. PROCEDURES Data pertaining to various types of biological samples obtained from reptiles with positive Salmonella culture results and the reptiles themselves were analyzed to determine period prevalence of and risk factors for various Salmonella-related outcomes. RESULTS Serovar distribution differences were identified for sample type, reptile phylogenetic family, and reptile origin and health. Salmonella enterica subsp enterica was the most common subspecies in Salmonella cultures (78/175 [45%]), identified across all reptilian taxa. Salmonella enterica subsp diarizonae was also common (42/175 [24%]) and was recovered almost exclusively from snakes (n = 33), many of which had been clinically ill (17). Clinically ill reptiles provided 37% (64) of Salmonella cultures. Factors associated with an increased risk of illness in reptiles with a positive culture result were carnivorous diet and prior confiscation. Snakes had a higher risk of illness than other reptile groups, whereas lizards had a lower risk. Bony changes, dermatitis, and anorexia were the most common clinical signs. CONCLUSIONS AND CLINICAL RELEVANCE This study provided new information on Salmonella infection or carriage and associated clinical disease in reptiles. Associations identified between serovars or subspecies and reptile groups or clinical disease can guide management of Salmonella-positive captive reptiles.

  16. [Rapid methods for the genus Salmonella bacteria detection in food and raw materials].

    Science.gov (United States)

    Sokolov, D M; Sokolov, M S

    2013-01-01

    The article considers sanitary and epidemiological aspects and the impact of Salmonella food poisoning in Russia and abroad. The main characteristics of the agent (Salmonella enterica subsp. Enteritidis) are summarized. The main sources of human Salmonella infection are products of poultry and livestock (poultry, eggs, dairy products, meat products, etc.). Standard methods of identifying the causative agent, rapid (alternative) methods of analysis of Salmonella using differential diagnostic medium (MSRV, Salmosyst, XLT4-agar, agar-Rambach et al.), rapid tests Singlepath-Salmonella and PCR (food proof Salmonella) in real time were stated. Rapid tests provide is a substantial (at 24-48 h) reducing the time to identify Salmonella.

  17. Persistence of fluoroquinolone-resistant Salmonella enterica serovar Kentucky from poultry and poultry sources in Nigeria

    DEFF Research Database (Denmark)

    Raufu, Ibrahim A.; Fashae, Kayode; Ameh, James A.

    2014-01-01

    Introduction: This study investigated the antimicrobial resistance and clonality of Salmonella enterica serotype Kentucky in poultry and poultry sources in Nigeria, and compared the isolates with the clone of S. Kentucky STI98-X1 CIPR using (PFGE) and (MIC). Methodology: Fecal samples from chickens...... and poultry sources (litter, water, rodent and lizard fecal samples) were collected from fourteen (14) poultry farms in 2007, 2010 and 2011 and were analyzed for S. Kentucky. Results and conclusions: Six percent of the samples were positive for S. Kentucky - all resistant to nalidixic acid and ciprofloxacin...

  18. Administration of acidified drinking water to finishing pigs in order to prevent Salmonella infections.

    Science.gov (United States)

    van der Wolf, P J; van Schie, F W; Elbers, A R; Engel, B; van der Heijden, H M; Hunneman, W A; Tielen, M J

    2001-07-01

    The aim of the study was to test whether acidified drinking water, with two millilitres of an acid mixture per litre, was able to reduce the number of Salmonella infections in finishing pig herds. In each compartment, half of the pens were supplied with acidified water and the other pens served as negative control. In three herds the required dose was not applied to the pigs as a result of various practical problems. In another herd, all pigs remained seronegative throughout the study. Analysis of the remaining three herds showed a large and significant treatment effect in one herd (Pdrinking nipples as a result of fungal growth in the pipelines.

  19. Effect of Pulsed Electric Field on Membrane Lipids and Oxidative Injury of Salmonella typhimurium.

    Science.gov (United States)

    Yun, Ou; Zeng, Xin-An; Brennan, Charles S; Han, Zhong

    2016-08-22

    Salmonella typhimurium cells were subjected to pulsed electric field (PEF) treatment at 25 kV/cm for 0-4 ms to investigate the effect of PEF on the cytoplasmic membrane lipids and oxidative injury of cells. Results indicated that PEF treatment induced a decrease of membrane fluidity of Salmonella typhimurium (S. typhimuriumi), possibly due to the alterations of fatty acid biosynthesis-associated gene expressions (down-regulation of cfa and fabA gene expressions and the up-regulation of fabD gene expression), which, in turn, modified the composition of membrane lipid (decrease in the content ratio of unsaturated fatty acids to saturated fatty acids). In addition, oxidative injury induced by PEF treatment was associated with an increase in the content of malondialdehyde. The up-regulation of cytochrome bo oxidase gene expressions (cyoA, cyoB, and cyoC) indicated that membrane damage was induced by PEF treatment, which was related to the repairing mechanism of alleviating the oxidative injury caused by PEF treatment. Based on these results, we achieved better understanding of microbial injury induced by PEF, suggesting that micro-organisms tend to decrease membrane fluidity in response to PEF treatment and, thus, a greater membrane fluidity might improve the efficiency of PEF treatment to inactivate micro-organisms.

  20. Salmonella typhi time to change empiric treatment

    DEFF Research Database (Denmark)

    Gade, C.; Engberg, J.; Weis, N.

    2008-01-01

    In the present case series report we describe seven recent cases of typhoid fever. All the patients were travellers returning from Pakistan, where typhoid is endemic. Salmonella typhi isolated from the patients by blood culture were reported as intermediary susceptible to fluoroquinolones in six...... out of seven cases. We recommend that empiric treatment of suspected cases of typhoid fever includes a third generation cephalosporin such as ceftriaxon. Furthermore, the present report stresses the importance of typhoid vaccination of travellers to areas where typhoid is endemic Udgivelsesdato: 2008/9/29...

  1. Salmonella Urinary Tract Infection Heralding Thoracic Mycotic Aneurysm: Case Report as Medical Apology

    Science.gov (United States)

    White, Jennifer L.; Golfus, Gabriel R.; Sadosty, Annie T.

    2017-01-01

    We report a case as a patient apology as a means of teaching other physicians about a unique presentation of a rare disease. Salmonella species are unusually isolated organisms in urine. In the case described, appreciation for the rarity of Salmonella species in the urine facilitated recognition of a serious disseminated Salmonella infection. Physicians should consider disseminated Salmonella infection, as was found in a patient with an aortic mycotic an eurysm, after isolation of Salmonella in urine despite an initially benign clinical presentation.

  2. An amino acid depleted cell-free protein synthesis system for the incorporation of non-canonical amino acid analogs into proteins.

    Science.gov (United States)

    Singh-Blom, Amrita; Hughes, Randall A; Ellington, Andrew D

    2014-05-20

    Residue-specific incorporation of non-canonical amino acids into proteins is usually performed in vivo using amino acid auxotrophic strains and replacing the natural amino acid with an unnatural amino acid analog. Herein, we present an efficient amino acid depleted cell-free protein synthesis system that can be used to study residue-specific replacement of a natural amino acid by an unnatural amino acid analog. This system combines a simple methodology and high protein expression titers with a high-efficiency analog substitution into a target protein. To demonstrate the productivity and efficacy of a cell-free synthesis system for residue-specific incorporation of unnatural amino acids in vitro, we use this system to show that 5-fluorotryptophan and 6-fluorotryptophan substituted streptavidin retain the ability to bind biotin despite protein-wide replacement of a natural amino acid for the amino acid analog. We envisage this amino acid depleted cell-free synthesis system being an economical and convenient format for the high-throughput screening of a myriad of amino acid analogs with a variety of protein targets for the study and functional characterization of proteins substituted with unnatural amino acids when compared to the currently employed in vivo methodologies. Copyright © 2014 Elsevier B.V. All rights reserved.

  3. Behavior of Salmonella spp. and natural microbiota on fresh-cut dragon fruits at different storage temperatures.

    Science.gov (United States)

    Sim, Hui Li; Hong, Yoon-Ki; Yoon, Won Byong; Yuk, Hyun-Gyun

    2013-01-01

    The aim of this study was to determine survival or growth of unadapted, acid-adapted and cold-stressed Salmonella spp., and natural microbiota on fresh-cut dragon fruits at different storage temperatures. Dragon fruits were sliced and spot inoculated with five-strain cocktail of Salmonella spp. at two inoculum levels (2.5 or 5.5 log CFU/g). Inoculated fruits were stored at 28°C for 48h and at 4°C and 12°C for 96 h. Salmonella population significantly increased by 2.4 to 3.0 log CFU/g at low inoculum level, whereas the numbers increased by 0.4 to 0.7 log CFU/g at the high inoculum level on fruits held at 28°C for 48h. Only unadapted and acid-adapted cells grew with 0.7 to 0.9log increase at the low inoculum level at 12°C for 96h. No significant growth was observed at both inoculum levels during storage at 4°C. Overall, acid, starved and cold adaptation of Salmonella spp. did not show significant difference in survival or growth on fresh-cut dragon fruits during storage compared to unadapted control cells. For natural microbiota on the fruit, mesophilic bacterial counts reached to 5-log CFU/g at 28 and 12°C by 9.9 and 52.9h. Similar with Salmonella spp. there was no growth of natural microbiota at 4°C. These results showed that Salmonella spp. could grow on fresh-cut dragon fruits under inappropriate storage conditions, indicating that fresh-cut dragon fruits could be a potential vehicle for salmonellosis. Thus, this study suggests that fresh-cut dragon fruits should be stored at 4°C to ensure the safety as well as to extend the shelf life of fresh-cut dragon fruits. Copyright © 2012 Elsevier B.V. All rights reserved.

  4. A FRET-based DNA biosensor tracks OmpR-dependent acidification of Salmonella during macrophage infection.

    Directory of Open Access Journals (Sweden)

    Smarajit Chakraborty

    2015-04-01

    Full Text Available In bacteria, one paradigm for signal transduction is the two-component regulatory system, consisting of a sensor kinase (usually a membrane protein and a response regulator (usually a DNA binding protein. The EnvZ/OmpR two-component system responds to osmotic stress and regulates expression of outer membrane proteins. In Salmonella, EnvZ/OmpR also controls expression of another two-component system SsrA/B, which is located on Salmonella Pathogenicity Island (SPI 2. SPI-2 encodes a type III secretion system, which functions as a nanomachine to inject bacterial effector proteins into eukaryotic cells. During the intracellular phase of infection, Salmonella switches from assembling type III secretion system structural components to secreting effectors into the macrophage cytoplasm, enabling Salmonella to replicate in the phagocytic vacuole. Major questions remain regarding how bacteria survive the acidified vacuole and how acidification affects bacterial secretion. We previously reported that EnvZ sensed cytoplasmic signals rather than extracellular ones, as intracellular osmolytes altered the dynamics of a 17-amino-acid region flanking the phosphorylated histidine. We reasoned that the Salmonella cytoplasm might acidify in the macrophage vacuole to activate OmpR-dependent transcription of SPI-2 genes. To address these questions, we employed a DNA-based FRET biosensor ("I-switch" to measure bacterial cytoplasmic pH and immunofluorescence to monitor effector secretion during infection. Surprisingly, we observed a rapid drop in bacterial cytoplasmic pH upon phagocytosis that was not predicted by current models. Cytoplasmic acidification was completely dependent on the OmpR response regulator, but did not require known OmpR-regulated genes such as ompC, ompF, or ssaC (SPI-2. Microarray analysis highlighted the cadC/BA operon, and additional experiments confirmed that it was repressed by OmpR. Acidification was blocked in the ompR null background in a

  5. Incidence and growth of Salmonella enterica on the peel and pulp of avocado (Persea americana) and custard apple (Annona squamosa).

    Science.gov (United States)

    Rezende, Ana Carolina B; Crucello, Juliana; Moreira, Rafael C; Silva, Beatriz S; Sant'Ana, Anderson S

    2016-10-17

    The aim of this study was to assess the incidence and to estimate the growth kinetic parameters (maximum growth rate, μ; lag time, λ; and maximum population, κ) of Salmonella on the peel and pulp of avocado (Perseaamericana var. americana) and custard apple (Annona squamosa L.) as affected by temperature (10-30°C). The incidence of Salmonella was assessed on the peel and pulp of the fruits (n=200 of each fruit), separately, totalizing 800 analyses. Only three samples of custard apple pulp were positive for Salmonella enterica and the three isolates recovered belonged to serotype S. Typhimurium. Salmonella was not recovered from avocado and custard apple peels and from avocado pulp. Generally, the substrate (pulp or peel) of growth did not affect μ values of S. enterica (p>0.05). Very similar μ values were found for S. enterica inoculated in custard apple and avocado. S. enterica presented the highest λ in the peel of the fruits. The growth of S. enterica resulted in larger λ in custard apple in comparison to avocado. For example, the λ of S. enterica in the pulp of custard apple and avocado were 47.0±0.78h and 10.0±3.78h, respectively. The lowest values of κ were obtained at the lower storage temperature conditions (10°C). For instance, κ values of 3.7±0.06log CFU/g and 2.9±0.03log CFU/g were obtained from the growth of S. enterica in avocado and custard apple pulps at 10°C (pavocado led to a κ value of 6.5±0.25log CFU/g, while in the peel led to a κ value of 4.6±0.23log CFU/g (pavocado comprises a better substrate than custard apple for the growth of S. enterica. The square root model fitted to the data obtained in this study and to the growth data available in the literature for other tropical low acid fruits indicated high variability in μ and λ of Salmonella. The results obtained in this study show that whole low acid tropical fruits can harbor Salmonella, and that this foodborne pathogen can not only survive but also grow both on the

  6. Test results of Salmonella typing by the NRLs-Salmonella in the Member States of the EU and the EnterNet Laboratories - Collaborative study VI on typing of Salmonella

    NARCIS (Netherlands)

    Korver H; Raes M; Maas HME; Ward LR; Wannet WJB; Henken AM; PHLS-Colindale/London; MGB; LIS

    2002-01-01

    Test results of Salmonella sero- and phage typing and antimicrobial susceptibility testing by the National Reference Laboratories for Salmonella in the Member States of the European Union and the EnterNet Laboratories: Collaborative study VI (2001) for Salmonella. The sixth collaborative typing

  7. Salmonella bacteraemia among healthcare workers and their dependents

    International Nuclear Information System (INIS)

    Raza, A.; Sultan, F.; Mahboob, A.; Nazeer, S. H.; Nizammudin, S.

    2014-01-01

    Objectives: To determine the incidence and resistance pattern of Salmonella infection in healthcare workers and their dependents. Methods: The retrospective analysis was conducted at Shaukat Khanum Memorial Cancer Hospital and Research Centre, Lahore, and comprised records of employees and their dependents with bacteraemia from January 2007 to December 2011. Person-years were calculated using data from the human resources department. SPSS 19 was used for statistical analyses. Results: Of the total 2532 records available, 82(3.23%) patients were identified with Salmonella bacteraemia. Of them, 34(41.5%) patients were in age group 1-10, 15(18.3%) in 11-20, 26(31.7%) in 21-30, and 7(8.5%) were above 30 years. Besides, 48(58.5%) were males. Salmonella typhi was found in 44(53.7%) patients, Salmonella paratyphi A in 35(42.7%) and Salmonella species in 3(3.7%) patients. The yearly incidence of Salmonella infection in the study population ranged from 206 to 596 per 100000 person-years. Ciprofloxacin resistance was noted to be 56 (68.2%) followed by Ampicillin 29 (35.3%) and Co-trimoxazole 24 (29.2%). No strains were resistant to Cefiximeor Ceftriaxone. Conclusion: The yearly incidence of Salmonella bacteraemia ranged from 200 to 600 per 100000 person years. There was significant quinolone resistance among the isolates. (author)

  8. A single-tube screen for Salmonella and Shigella.

    Science.gov (United States)

    Procop, Gary W; Wallace, Jacqueline D; Tuohy, Marion J; Lasalvia, Margret M; Addison, Rachel M; Reller, L Barth

    2008-08-01

    Salmonella and Shigella species are routinely sought in stool specimens submitted for culture. It is a common practice to screen lactose-negative colonies by using triple sugar iron agar, lysine iron agar, and Christensen urea agar to determine if further identification is necessary. We designed and evaluated a novel combination of media, which are layered in a single tube, for screening isolates suspected to possibly represent Salmonella or Shigella. We tested this media combination with 106 Salmonella, 56 Shigella, and 56 other gram-negative bacilli. All Salmonella and Shigella isolates tested were appropriately characterized as possible Salmonella or Shigella by using an algorithm developed for use with this media combination. Similarly, 53 (95%) of 56 other gram-negative bacilli were appropriately screened as non -Salmonella and non -Shigella isolates. This unique media combination provides the most important biochemical reactions needed to screen for Salmonella and Shigella in a single-tube format, which decreases labor by two thirds (ie, 1 tube is inoculated vs 3).

  9. Salmonella serovar spectrum associated with reptiles in Poland

    Directory of Open Access Journals (Sweden)

    Tomasz Piasecki

    2014-01-01

    Full Text Available This study aimed to evaluate the incidence of Salmonella isolates from a wide variety of reptiles in Poland. A total of 374 faecal samples from chelonians, lizards and snakes were collected between 2009 and 2012. The nested, two-step PCR and multiplex PCR were performed to access the incidence and to characterize Salmonella isolates. Salmonella strains were found in 122 of 374 samples (32.6%. Among the different reptilian species, Salmonella strains were found in 58 samples from lizards (38.9%, 31 samples from snakes (28.7% and 33 samples from chelonians (28.2%. Of the total of 122 strains, 72 belonged to the species Salmonella enterica subsp. enterica, 20 to the species S. enterica subs. salamae or S. enterica subs. houtanae. The incidence of S. enterica subs. diarizonae and S. enterica subs. indica was low, constituting less than 3.5% of the examined population. The findings show that reptiles can be considered as a reservoir for Salmonella and hence could pose a zoonotic hazard. In addition, multiplex PCR assay is a rapid, specific and easy-to-perform method and might be applied for rapid screening of large numbers of Salmonella samples.

  10. Salmonella detection in a microfluidic channel using orbiting magnetic beads

    Science.gov (United States)

    Ballard, Matt; Mills, Zachary; Owen, Drew; Hanasoge, Srinivas; Hesketh, Peter; Alexeev, Alexander

    2015-03-01

    We use three-dimensional simulations to model the detection of salmonella in a complex fluid sample in a microfluidic channel. Salmonella is captured using magnetic microbeads orbiting around soft ferromagnetic discs at the microchannel bottom subjected to a rotating external magnetic field. Numerical simulations are used to model the dynamics of salmonella and microbeads throughout the detection process. We examine the effect of the channel geometry on the salmonella capture, and the forces applied to the salmonella as it is dragged through the fluid after capture. Our findings guide the design of a lab-on-a-chip device to be used for detection of salmonella in food samples in a way that ensures that salmonella captured by orbiting microbeads are preserved until they can be extracted from the system for testing, and are not washed away by the fluid flow or damaged due to the experience of excessive stresses. Such a device is needed to detect bacteria at the food source and prevention of consumption of contaminated food, and also can be used for the detection of a variety of biomaterials of interest from complex fluid samples. Support from USDA and NSF is gratefully acknowledged.

  11. Elimination of salmonella from fermented pork by gamma irradiation

    International Nuclear Information System (INIS)

    Noochpramul, K.; Loaharanu, P.

    1974-01-01

    A fermented pork product, locally known as ''Nham'', is usually contaminated with salmonella and occasionally with Trichinella spiralis and Taenea solium. This product is always eaten raw as cooking destroys its delicate flavour. A survey made on the MPN of salmonella revealed that much less than 100 salmonella was found in one gram of the product. Nham was inoculated with S. derby, S. anatum, S. newport, or S. paratyphi B, the most common serotypes of salmonella found in this product, at 10 6 , 10 4 , or 10 2 per gram. The inoculated product was irradiated by the gamma beam-650 Co-60 irradiator at 0, 0.1, 0.2, 0.3 or 0.4 Mrad. Dosage at 0.4 Mrad eliminated salmonella as much as 10 6 per g; 0.3 Mrad eliminated 10 6 /g of S. newport and S. paratyphi B and 10 4 /g of S. derby and S. anatum; and 0.2 Mrad eliminated 10 2 /g of all serotypes of salmonella in the product. No changes in the organoleptic properties of irradiated Nham was found when irradiated at 0.3 Mrad or less. Dosage at 0.2 Mrad appeared to be sufficient for commercial irradiation of Nham for the elimination of salmonella

  12. O:2-CRM(197) conjugates against Salmonella Paratyphi A.

    Science.gov (United States)

    Micoli, Francesca; Rondini, Simona; Gavini, Massimiliano; Lanzilao, Luisa; Medaglini, Donata; Saul, Allan; Martin, Laura B

    2012-01-01

    Enteric fevers remain a common and serious disease, affecting mainly children and adolescents in developing countries. Salmonella enterica serovar Typhi was believed to cause most enteric fever episodes, but several recent reports have shown an increasing incidence of S. Paratyphi A, encouraging the development of a bivalent vaccine to protect against both serovars, especially considering that at present there is no vaccine against S. Paratyphi A. The O-specific polysaccharide (O:2) of S. Paratyphi A is a protective antigen and clinical data have previously demonstrated the potential of using O:2 conjugate vaccines. Here we describe a new conjugation chemistry to link O:2 and the carrier protein CRM(197), using the terminus 3-deoxy-D-manno-octulosonic acid (KDO), thus leaving the O:2 chain unmodified. The new conjugates were tested in mice and compared with other O:2-antigen conjugates, synthesized adopting previously described methods that use CRM(197) as carrier protein. The newly developed conjugation chemistry yielded immunogenic conjugates with strong serum bactericidal activity against S. Paratyphi A.

  13. O:2-CRM(197 conjugates against Salmonella Paratyphi A.

    Directory of Open Access Journals (Sweden)

    Francesca Micoli

    Full Text Available Enteric fevers remain a common and serious disease, affecting mainly children and adolescents in developing countries. Salmonella enterica serovar Typhi was believed to cause most enteric fever episodes, but several recent reports have shown an increasing incidence of S. Paratyphi A, encouraging the development of a bivalent vaccine to protect against both serovars, especially considering that at present there is no vaccine against S. Paratyphi A. The O-specific polysaccharide (O:2 of S. Paratyphi A is a protective antigen and clinical data have previously demonstrated the potential of using O:2 conjugate vaccines. Here we describe a new conjugation chemistry to link O:2 and the carrier protein CRM(197, using the terminus 3-deoxy-D-manno-octulosonic acid (KDO, thus leaving the O:2 chain unmodified. The new conjugates were tested in mice and compared with other O:2-antigen conjugates, synthesized adopting previously described methods that use CRM(197 as carrier protein. The newly developed conjugation chemistry yielded immunogenic conjugates with strong serum bactericidal activity against S. Paratyphi A.

  14. Vaccination against Salmonella Infection: the Mucosal Way.

    Science.gov (United States)

    Gayet, Rémi; Bioley, Gilles; Rochereau, Nicolas; Paul, Stéphane; Corthésy, Blaise

    2017-09-01

    Salmonella enterica subspecies enterica includes several serovars infecting both humans and other animals and leading to typhoid fever or gastroenteritis. The high prevalence of associated morbidity and mortality, together with an increased emergence of multidrug-resistant strains, is a current global health issue that has prompted the development of vaccination strategies that confer protection against most serovars. Currently available systemic vaccine approaches have major limitations, including a reduced effectiveness in young children and a lack of cross-protection among different strains. Having studied host-pathogen interactions, microbiologists and immunologists argue in favor of topical gastrointestinal administration for improvement in vaccine efficacy. Here, recent advances in this field are summarized, including mechanisms of bacterial uptake at the intestinal epithelium, the assessment of protective host immunity, and improved animal models that closely mimic infection in humans. The pros and cons of existing vaccines are presented, along with recent progress made with novel formulations. Finally, new candidate antigens and their relevance in the refined design of anti- Salmonella vaccines are discussed, along with antigen vectorization strategies such as nanoparticles or secretory immunoglobulins, with a focus on potentiating mucosal vaccine efficacy. Copyright © 2017 American Society for Microbiology.

  15. Population structure of Salmonella investigated by amplified fragment length polymorphism

    DEFF Research Database (Denmark)

    Torpdahl, M.; Ahrens, Peter

    2004-01-01

    Aims: This study was undertaken to investigate the usefulness of amplified fragment length polymorphism (AFLP) in determining the population structure of Salmonella. Methods and Results: A total of 89 strains were subjected to AFLP analysis using the enzymes BglII and BspDI, a combination...... that is novel in Salmonella. Both species S. bongori and S. enterica and all subsp. of S. enterica were represented with emphasis on S. enterica subsp. enterica using a local strain collection and strains from the Salmonella Reference Collection B (SARB). The amplified fragments were used in a band...

  16. Epidemiology and control measures for Salmonella in pigs and pork

    DEFF Research Database (Denmark)

    Wong, Danilo Lo Fo; Hald, Tine; Wolf, P. J. van der

    2002-01-01

    at the abattoir and during lairage, exposing negative pigs to Salmonella. Positive pigs carry Salmonella on the skin, in the gastro-intestinal system or in the mouth. The (cross-)contamination of carcasses is basically a matter of redistributing the Salmonella bacteria from the positive pigs during the various...... slaughter processes. Although the manufacturing and retail levels of pork production depend on the quality of raw materials that are delivered, they share the responsibility for the quality and safety of the end products reaching the consumer. At this level and onwards, the three main factors which...

  17. Prevalence of Salmonella spp. in Oysters in the United States

    OpenAIRE

    Brands, Danielle A.; Inman, Allison E.; Gerba, Charles P.; Maré, C. John; Billington, Stephen J.; Saif, Linda A.; Levine, Jay F.; Joens, Lynn A.

    2005-01-01

    Food-borne diseases such as salmonellosis can be attributed, in part, to the consumption of raw oysters. To determine the prevalence of Salmonella spp. in oysters, oysters harvested from 36 U.S. bays (12 each from the West, East, and Gulf coasts in the summer of 2002, and 12 bays, four per coast, in the winter of 2002-2003) were tested. Salmonella was isolated from oysters from each coast of the United States, and 7.4% of all oysters tested contained Salmonella. Isolation tended to be bay spe...

  18. Salmonella contamination of hatching and table eggs: a comparison.

    OpenAIRE

    Poppe, C; Duncan, C L; Mazzocco, A

    1998-01-01

    This study determined and compared Salmonella contamination rates of pools of surplus, early and culled hatching eggs from layer and broiler breeder flocks, and of pools of early and regular table eggs from layer flocks. Each pool contained 6 eggs. Five methods were used for the isolation of Salmonella. Nine of 126 pools of culled layer hatching eggs, 2 of 126 pools of surplus layer hatching eggs, and one of 126 pools of early layer hatching eggs were contaminated with Salmonella. All 126 poo...

  19. Test results of Salmonella sero- and phage typing by the National Reference Laboratories in the Member States of the European Union

    NARCIS (Netherlands)

    Raes M; Ward LR; Maas HME; Wannet WJB; Henken AM; MGB; PHLS/LEP; LIS

    2001-01-01

    Het vijfde Salmonella typerings ringonderzoek is georganiseerd door het Communautair Referentie Laboratorium voor Salmonella (CRL-Salmonella, Bilthoven) in samenwerking met de Public Health Laboratory Services (PHLS, Londen). Alle 17 Nationale Referentie Laboratoria voor Salmonella

  20. Effect of lime juice on Vibrio parahaemolyticus and Salmonella enterica inactivation during the preparation of the raw fish dish ceviche.

    Science.gov (United States)

    Mathurand, Prateek; Schaffner, Donald W

    2013-06-01

    Ceviche is a raw fish dish common in Peru and other Latin American counties. The most characteristic feature of ceviche is the use of lime juice for marinating or "cooking" the raw fish. Confirmed cases of cholera in Peru, New Jersey, and Florida have been associated with ceviche. Although the effect of organic acids on pathogenic bacteria has been well characterized, few data exist on the effect of these acids in seafood systems. The objective of the study was to evaluate the effects of lime juice marination on pathogens likely to be present in ceviche. Tilapia (Oreochromis niloticus) fillet pieces were inoculated with Vibrio parahaemolyticus and Salmonella enterica (>7 log CFU/g) and incubated at 25 and 4°C for 30 or 120 min in the presence of fresh lime juice at concentrations typical for the preparation of ceviche. Similar levels of cells were also inoculated into fresh lime juice without tilapia. Surviving cells were enumerated on selective (xylose lysine Tergitol 4 and thiosulfate-bile-citrate-sucrose) and nonselective (tryptic soy agar) media. V. parahaemolyticus levels were reduced to below detection limits (∼5-log reduction) under all conditions studied. Salmonella strains on tilapia were much more resistant to inactivation and were only slightly reduced (∼1- to 2-log reduction). Salmonella and V. parahaemolyticus inoculated directly into lime juice without tilapia were all reduced to below detection limits (∼5-log reduction). A typical ceviche recipe reduces V. parahaemolyticus risk significantly but is less effective for control of S. enterica.

  1. Sobrevivência e perfil de resistência a antimicrobianos de Salmonella sp. isoladas em um sistema de tratamento de dejetos de suínos Survival and resistance patterns of Salmonella sp. isolated in a pig slurry treatment plant

    Directory of Open Access Journals (Sweden)

    Verônica Schmidt

    2003-10-01

    Full Text Available No presente estudo, foi avaliada a sobrevivência de Salmonella sp., presente em dejetos suínos, durante tratamento em um sistema de separação física e lagoas de estabilização ligadas em série. Nas amostras de Salmonella sp. isoladas foi determinado o perfil de resistência pelo método de difusão em ágar, usando 14 antimicrobianos. Das 20 coletas realizadas, foi possível isolar Salmonella sp. em 13 coletas no ponto correspondente ao início do sistema de tratamento e em apenas uma no ponto final do mesmo. Amostras de Salmonella sp. isoladas (161/163 pertenciam ao sorotipo Typhimurium e demonstraram resistência contra sulfonamida (100%, tetraciclina (99,4%, estreptomicina (90,1%, sulfa/trimetoprima (84,5%, ácido nalidíxico (77,6%, ampicilina (76,4%, cloranfenicol (29,2%, cefaclor (25,5%, tobramicina (13,7%, gentamicina (6,2%, amoxacilina/ácido clavulânico (5%, neomicina (5% e amicacina (3,7%. A maioria (94,5% das amostras isoladas foram resistente a 4 ou mais antimicrobianos e apresentaram grande variabilidade nos perfis de resistência. O nível de resistência e a variabilidade dos perfis mantiveram-se em nível semelhante ao longo do sistema.The survival of Salmonella sp. in pig slurry submitted to treatment in successive stabilization ponds on a pig-breeding farm was investigated. Furthermore, the isolated Salmonella strains were tested for their resistance against 14 antibiotics, using the agar diffusion method. Of a total of 20 samples taken from different points in the stabilization ponds system, 13 were positive for Salmonella sp. in the beginning and only one at the end of the system. Most of the isolated Salmonella strains (161/163 belonged to sorovar Typhimurium. These strains were resistant to sulfonamide (100%, tetracycline (9.4%, sulfamethoxazole/trimethoprin (84.5%, ampicillin (76.4%, cloramphenicol (29.2%, streptomycin (90.1%, nalidixic acid (77.6%, tobramycin (13.7%, neomycin (5%, amikacin (3.7%, cefaclor (25

  2. Effectiveness of superheated steam for inactivation of Escherichia coli O157:H7, Salmonella Typhimurium, Salmonella Enteritidis phage type 30, and Listeria monocytogenes on almonds and pistachios.

    Science.gov (United States)

    Ban, Ga-Hee; Kang, Dong-Hyun

    2016-03-02

    This study was undertaken to evaluate the effectiveness of superheated steam (SHS) on the inactivation of Escherichia coli O157:H7, Salmonella Typhimurium, Salmonella Enteritidis phage type (PT) 30 and Listeria monocytogenes on almonds and in-shell pistachios and to determine the effect of superheated steam heating on quality by measuring color and texture changes. Almonds and in-shell pistachios inoculated with four foodborne pathogens were treated with saturated steam (SS) at 100 °C and SHS at 125, 150, 175, and 200 °C for various times. Exposure of almonds and pistachios to SHS for 15 or 30s at 200 °C achieved >5l og reductions among all tested pathogens without causing significant changes in color values or texture parameters (P>0.05). For both almonds and pistachios, acid and peroxide values (PV) following SS and SHS treatment for up to 15s and 30s, respectively, were within the acceptable range (PV<1.0 meq/kg). These results show that thermal application of 200 °C SHS treatment for 15s and 30s did not affect the quality of almonds and pistachios, respectively. Therefore, SHS treatment is a very promising alternative technology for the tree nuts industry by improving inactivation of foodborne pathogens on almonds and pistachios while simultaneously reducing processing time. Copyright © 2016 Elsevier B.V. All rights reserved.

  3. Resuscitation of the viable but non-culturable state of Salmonella enterica serovar Oranienburg by recombinant resuscitation-promoting factor derived from Salmonella Typhimurium strain LT2.

    Science.gov (United States)

    Panutdaporn, N; Kawamoto, K; Asakura, H; Makino, S-I

    2006-02-15

    A gene encoding the resuscitation-promoting factor (Rpf) from Salmonella Typhimurium LT2 was cloned and characterized. The amino acid sequence encoded by S. Typhimurium LT2 rpf gene shares 24.2% homology with Micrococcus luteus Rpf, which is secreted by growing cells, and required to resuscitate from viable but non-culturable (VNC) state. The S. Typhimurium LT2 rpf gene is 696 bp long, and shared a conserved segment with Salmonella enterica serovar Oranienburg (99.4%). Recombinant Rpf (rRpf) proteins of S. Typhimurium LT2 after expression in E. coli BL21 harboring the pET15-b plasmid was approximately 25 kDa. Since S. Oranienburg cells are relatively quick to enter the VNC state just after incubating in the presence of 7% NaCl at 37 degrees C for 3 days, we evaluated the biological effect of rRpf by using S. Oranienburg VNC cells. The rRpf not only promoted proliferation but also induced resuscitation of VNC cells to the culturable state in a dose-dependent manner. Therefore, rRpf may be useful for detection of bacterial contaminants present in the VNC form in food samples and the environment.

  4. Test results of serotyping Salmonella strains in the Member States of the European Union (A collaborative study amongst the National Reference Laboratories for Salmonella)

    NARCIS (Netherlands)

    Voogt N; Maas HME; Leeuwen WJ van; Henken AM; MGB

    1997-01-01

    Het Communautair Referentie Laboratorium (CRL) voor Salmonella heeft een ringonderzoek voor de serotypering van Salmonella georganiseerd. De Nationale Referentie Laboratoria (NRLs) voor Salmonella uit 14 van de 15 lidstaten van de Europese Unie deden aan het onderzoek mee. Het doel was te

  5. The transcriptional programme of Salmonella enterica serovar Typhimurium reveals a key role for tryptophan metabolism in biofilms.

    LENUS (Irish Health Repository)

    Hamilton, Shea

    2009-12-11

    Abstract Background Biofilm formation enhances the capacity of pathogenic Salmonella bacteria to survive stresses that are commonly encountered within food processing and during host infection. The persistence of Salmonella within the food chain has become a major health concern, as biofilms can serve as a reservoir for the contamination of food products. While the molecular mechanisms required for the survival of bacteria on surfaces are not fully understood, transcriptional studies of other bacteria have demonstrated that biofilm growth triggers the expression of specific sets of genes, compared with planktonic cells. Until now, most gene expression studies of Salmonella have focused on the effect of infection-relevant stressors on virulence or the comparison of mutant and wild-type bacteria. However little is known about the physiological responses taking place inside a Salmonella biofilm. Results We have determined the transcriptomic and proteomic profiles of biofilms of Salmonella enterica serovar Typhimurium. We discovered that 124 detectable proteins were differentially expressed in the biofilm compared with planktonic cells, and that 10% of the S. Typhimurium genome (433 genes) showed a 2-fold or more change in the biofilm compared with planktonic cells. The genes that were significantly up-regulated implicated certain cellular processes in biofilm development including amino acid metabolism, cell motility, global regulation and tolerance to stress. We found that the most highly down-regulated genes in the biofilm were located on Salmonella Pathogenicity Island 2 (SPI2), and that a functional SPI2 secretion system regulator (ssrA) was required for S. Typhimurium biofilm formation. We identified STM0341 as a gene of unknown function that was needed for biofilm growth. Genes involved in tryptophan (trp) biosynthesis and transport were up-regulated in the biofilm. Deletion of trpE led to decreased bacterial attachment and this biofilm defect was restored by

  6. Study of the role of efflux pump in ciprofloxacin resistance in Salmonella enterica serotype Typhi

    Directory of Open Access Journals (Sweden)

    V Sharma

    2013-01-01

    Full Text Available Purpose: There are increasing reports on failure of clinical response to ciprofloxacin in typhoid fever despite the strain being sensitive to drug in in-vitro using standard guidelines and showing mutations in DNA gyrase. But this increased MIC and clinical failures with ciprofloxacin are not always co-related with mutations presently identified in gyrA and parC genes. This shows that there may be other mechanisms such as an active drug efflux pump responsible as has been shown in other Enterobacteriaceae. This study was carried out to determine the role of efflux pump in Salmonella Typhi isolates. Materials and Methods : Total 25 already characterized nalidixic acid sensitive and nalidixic acid resistant S. Typhi strains with different range of ciprofloxacin MIC were included to study the role of efflux pump in the presence of CCCP (efflux pump inhibitor. For genotypic characterization, the entire acrR gene was sequenced to confirm the presence of any mutation in the gene. Results: The MIC of ciprofloxacin remained same in the presence and absence of CCCP in the studied strains and no significant mutations were found in the acrR gene in any of the isolates studied. Conclusions: No role of efflux pump in ciprofloxacin resistance was found in strains studied. There is a need to explore further mechanism of ciprofloxacin resistance in Salmonella Typhi.

  7. Third-Generation Cephalosporin-Resistant Non-Typhoidal Salmonella Isolated from Human Feces in Japan.

    Science.gov (United States)

    Saito, Satomi; Koori, Yoshio; Ohsaki, Yusuke; Osaka, Shunsuke; Oana, Kozue; Nagano, Yukiko; Arakawa, Yoshichika; Nagano, Noriyuki

    2017-05-24

    β-lactamase genes were detected and characterized from 10 non-typhoidal Salmonella (NTS) clinical isolates resistant to third-generation cephalosporins collected between 2012 and 2014 in Japan. Five strains showed cefotaxime minimum inhibitory concentration (MIC) ≥ 64 μg/ml and positive clavulanic acid inhibition results. The bla CTX-M-2 was detected in 3 strains (serotypes Stanley and Muenchen), whereas bla TEM-52 (serotype Manhattan) and bla SHV-12 (serotype Infantis) were each found in 1 strain. bla CMY-2 was detected in the remaining 5 strains (serotypes Infantis, Rissen, Newport, and Saintpaul) with cefotaxime MICs of 4-32 μg/ml and positive cloxacillin- and 3-aminophenylboronic acid- based inhibition tests. ISEcp1 was located upstream of the bla CMY-2 in 4 strains and of the bla CTX-M-2 in 1 strain. Incompatibility (Inc)A/C, IncP, and IncI1 plasmids were present in the strains harboring bla CMY-2 , which were detected predominantly in this study. Acquisition of resistance to third-generation cephalosporins by invasive NTS may limit therapeutic options for severe systemic infections and causing serious public health problems. Though such resistant clinical isolates are still rare in Salmonella species in Japan, our findings reveal the presence of cephem-resistant NTS in food handlers, thus emphasizing the necessity of more systematic nationwide investigations.

  8. Antimicrobial susceptibility and internalization of Salmonella Typhimurium in vacuum-tumbled marinated beef products.

    Science.gov (United States)

    Pokharel, S; Brooks, J C; Martin, J N; Brashears, M M

    2016-12-01

    As the incidence of multidrug resistance (MDR) Salmonella enterica serotype Typhimurium is increasing, data regarding the antimicrobial interventions and pathogen internalization in marinated meat products are important. This study evaluated the antimicrobial intervention and internalization of Salm. Typhimurium in marinated beef sirloin steaks. Beef bottom sirloin flaps (IMPS #185A; USDA Select) inoculated (10 8  log 10  CFU ml -1 ) with Salm. Typhimurium were sprayed (lactic acid (4%) and buffered vinegar (2%)) prior to vacuum-tumbled marination (0·35% sodium chloride and 0·45% sodium tripolyphosphate) for 30 min. Pathogen presence after antimicrobial spray, vacuum-tumbled marination, and translocation was determined by direct plating on Xylose Lysine Deoxycholate (XLD) agar with tryptic soy agar (TSA) overlay. The data imply varied internalization and antimicrobial susceptibility pattern of Salm. Typhimurium in marinated meat. Lactic acid (4%) spray (P internalization and potential survival of Salmonella spp. in marinated beef products is a major concern. These results highlight the internalization of pathogens in vacuum-tumbled meat products and emphasize the importance of considering these products as nonintact. Similarly, these data confirm the efficacy and utility of interventions prior to vacuum-tumbled marination. Further research is needed to identify additional strategies to mitigate internalization and translocation of pathogens into vacuum-marinated meat products. © 2016 The Society for Applied Microbiology.

  9. Effects of chemical and physical mutagens on the frequency of a large genetic duplication in Salmonella typhimurium. I

    International Nuclear Information System (INIS)

    Hoffman, G.R.; Morgan, R.W.

    1978-01-01

    In Salmonella typhimurium a simple selection has been described to detect bacteria that are merodiploid for almost one-third of the chromosome. The selective procedure is based upon improved utilization of L-malate as the sole carbon source in merodiploid strains. The spontaneous frequency of the duplication in haploid strains is approximately 10 -4 per cell plated. Following the exposure of a haploid strain to mutagenic agents, there is a dose-dependent increase in the duplication frequency above the spontaneous level. In this paper the authors describe the induction of genetic duplications in Salmonella typhimurium by X-rays, ultraviolet light (UV), ethyl methanesulfonate (EMS), nitrous acid, and the azaacridine half mustard, ICR-372. (Auth.)

  10. Analysis of the intestinal microbiota of oligo-saccharide fed mice exhibiting reduced resistance to Salmonella infection

    DEFF Research Database (Denmark)

    Petersen, Anne; Bergström, Anders; Andersen, Jens Bo

    2010-01-01

    recently demonstrated a reduced resistance to Salmonella infection in mice fed diets containing fructo-oligosaccharides (FOS) or xylo-oligosaccharides (XOS). In the present study, faecal and caecal samples from the same mice were analysed in order to study microbial changes potentially explaining...... the observed effects on the pathogenesis of Salmonella. Denaturing gradient gel electrophoresis revealed that the microbiota in faecal samples from mice fed FOS or XOS were different from faecal samples collected before the feeding trial as well as from faecal profiles generated from control animals...... of short-chain fatty acids was recorded. In conclusion, diets supplemented with FOS or XOS induced a number of microbial changes in the faecal microbiota of mice. The observed effects of XOS were qualitatively similar to those of FOS, but the most prominent bifidogenic effect was seen for XOS. An increased...

  11. Multiple antigens of Yersinia pestis delivered by live recombinant attenuated Salmonella vaccine strains elicit protective immunity against plague.

    Science.gov (United States)

    Sanapala, Shilpa; Rahav, Hannah; Patel, Hetal; Sun, Wei; Curtiss, Roy

    2016-05-05

    Based on our improved novel Salmonella vaccine delivery platform, we optimized the recombinant attenuated Salmonella typhimurium vaccine (RASV) χ12094 to deliver multiple Yersinia pestis antigens. These included LcrV196 (amino acids, 131-326), Psn encoded on pYA5383 and F1 encoded in the chromosome, their synthesis did not cause adverse effects on bacterial growth. Oral immunization with χ12094(pYA5383) simultaneously stimulated high antibody titers to LcrV, Psn and F1 in mice and presented complete protection against both subcutaneous (s.c.) and intranasal (i.n.) challenges with high lethal doses of Y. pestis CO92. Moreover, no deaths or other disease symptoms were observed in SCID mice orally immunized with χ12094(pYA5383) over a 60-day period. Therefore, the trivalent S. typhimurium-based live vaccine shows promise for a next-generation plague vaccine. Copyright © 2016 Elsevier Ltd. All rights reserved.

  12. Effect of organic acids on biofilm formation and quorum signaling of pathogens from fresh fruits and vegetables.

    Science.gov (United States)

    Amrutha, Balagopal; Sundar, Kothandapani; Shetty, Prathapkumar Halady

    2017-10-01

    Organic acids are known to be used as food preservatives due to their antimicrobial potential. This study evaluated the ability of three organic acids, namely, acetic acid, citric acid and lactic acid to manage E. coli and Salmonella sp. from fresh fruits and vegetables. Effect of these organic acids on biofilm forming ability and anti-quorum potential was also investigated. The effect of organic acids on inactivation of E. coli and Salmonella sp. on the surface of a selected vegetable (cucumber) was determined. The minimum inhibitory concentration of the organic acids were found to be 1.5, 2 and 0.2% in E. coli while it was observed to be 1, 1.5 and 1% in Salmonella sp. for acetic, citric and lactic acids respectively. Maximum inhibition of biofilm formation was recorded at 39.13% with lactic acid in E. coli and a minimum of 22.53% with citric acid in Salmonella sp. EPS production was affected in E. coli with lactic acid showing reduction by 13.42% while citric acid and acetic acid exhibited only 6.25% and 10.89% respectively. Swimming and swarming patterns in E. coli was notably affected by both acetic and lactic acids. Lactic and acetic acids showed higher anti-quorum sensing (QS) potential when compared to citric acid. 2% lactic acid showed a maximum inhibition of violacein production by 37.7%. Organic acids can therefore be used as potential quorum quenching agents in food industry. 2% lactic acid treatment on cucumber demonstrated that it was effective in inactivating E. coli and Salmonella sp. There was 1 log reduction in microbial count over a period of 6 days after the lactic acid treatment. Thus, organic acids can act as effective potential sanitizers in reducing the microbial load associated with fresh fruits and vegetables. Copyright © 2017 Elsevier Ltd. All rights reserved.

  13. Changes in thermo-tolerance and survival under simulated gastrointestinal conditions of Salmonella Enteritidis PT4 and Salmonella Typhimurium PT4 in chicken breast meat after exposure to sequential stresses.

    Science.gov (United States)

    Melo, Adma Nadja Ferreira de; Souza, Geany Targino de; Schaffner, Donald; Oliveira, Tereza C Moreira de; Maciel, Janeeyre Ferreira; Souza, Evandro Leite de; Magnani, Marciane

    2017-06-19

    This study assessed changes in thermo-tolerance and capability to survive to simulated gastrointestinal conditions of Salmonella Enteritidis PT4 and Salmonella Typhimurium PT4 inoculated in chicken breast meat following exposure to stresses (cold, acid and osmotic) commonly imposed during food processing. The effects of the stress imposed by exposure to oregano (Origanum vulgare L.) essential oil (OVEO) on thermo-tolerance were also assessed. After exposure to cold stress (5°C for 5h) in chicken breast meat the test strains were sequentially exposed to the different stressing substances (lactic acid, NaCl or OVEO) at sub-lethal amounts, which were defined considering previously determined minimum inhibitory concentrations, and finally to thermal treatment (55°C for 30min). Resistant cells from distinct sequential treatments were exposed to simulated gastrointestinal conditions. The exposure to cold stress did not result in increased tolerance to acid stress (lactic acid: 5 and 2.5μL/g) for both strains. Cells of S. Typhimurium PT4 and S. Enteritidis PT4 previously exposed to acid stress showed higher (pthermo-tolerance in both strains. The cells that survived the sequential stress exposure (resistant) showed higher tolerance (pthermo-tolerance and enhance the survival under gastrointestinal conditions of S. Enteritidis PT4 and S. Typhimurium PT4. Copyright © 2017 Elsevier B.V. All rights reserved.

  14. Epidemiological Investigation of Salmonella enterica Serovar Kedougou in Thailand

    DEFF Research Database (Denmark)

    Pornruangwong, Srirat; Hendriksen, Rene S.; Pulsrikarn, Chaiwat

    2011-01-01

    with Salmonella Kedougou isolates of human origin from United States and of animal origin from the United Kingdom. Methods: Data from 13,976 Salmonella infections of which 253 were Salmonella Kedougou collected in Thailand between 2002 and 2008 were analyzed by logistic regression. Antimicrobial susceptibility...... association, whereas the majority of the animal isolates from United Kingdom clustered separately. Conclusions: This study reveals Salmonella Kedougou as a major cause of human infections in northern Thailand especially during the hot period and suggests a global spread probably due to travel. The clonal...... types causing infections in humans differed from those observed in animals in United Kingdom, which suggests the absence of an epidemiological link and could suggest differences in virulence. The high frequency of antimicrobial resistance, including emergence of resistance to fluoroquinolones and third...

  15. Salmonellae carrier status of food vendors in Kumasi, Ghana | Feglo ...

    African Journals Online (AJOL)

    230 females of 28 males) healthy food vendors for Salmonella typhi, and S. paratyphi A, B, and C, using stool culture, the widal test, and standard microbiological identification methods. Main outcome measures: Prevalence of chronic typhoidal ...

  16. Salmonella Source Attribution in Japan by a Microbiological Subtyping Approach

    DEFF Research Database (Denmark)

    Toyofuku, Hajime; Pires, Sara Monteiro; Hald, Tine

    2011-01-01

    In order to estimate the number of human Salmonella infections attributable to each of major animal-food source, and help identifying the best Salmonella intervention strategies, a microbial subtyping approach for source attribution was applied. We adapted a Bayesian model that attributes illnesses......-food sources, subtype-related factors, and source-related factors. National-surveillance serotyping data from 1998 to 2007 were applied to the model. Results suggested that the relative contribution of the sources to salmonellosis varied during the 10 year period, and that eggs are the most important source...... to specific sources and allows for the estimation of the differences in the ability of Salmonella subtypes and food types to result in reported salmonellosis. The number of human cases caused by different Salmonella subtypes is estimated as a function of the prevalence of these subtypes in the animal...

  17. Prevalence of Salmonella among waterfowl along the Texas Gulf coast.

    Science.gov (United States)

    Grigar, M K; Cummings, K J; Rankin, S C

    2017-12-01

    Migratory waterfowl may play a role in the ecology and transmission of zoonotic pathogens, given their ability to travel long distances and their use of varied habitats. Our objectives were to estimate the prevalence of Salmonella among waterfowl along the Texas Gulf coast and to characterize the isolates. Faecal samples were collected from hunter-harvested waterfowl at four wildlife management areas from September through November, 2016. Standard bacteriologic culture methods were used to isolate Salmonella from samples, and isolates were characterized by serotyping and anti-microbial susceptibility testing. The apparent prevalence of faecal Salmonella shedding was 0.5% (2/375). Serotypes identified were Thompson and Braenderup, and both isolates were susceptible to all anti-microbial agents tested. Although faecal contamination of agricultural fields or surface waters could serve as a potential source of zoonotic Salmonella transmission, waterfowl along the Gulf coast during the fall hunting season appear to pose minimal risk. © 2017 Blackwell Verlag GmbH.

  18. New paradigms for Salmonella source attribution based on microbial subtyping.

    NARCIS (Netherlands)

    Mughini-Gras, Lapo; Franz, Eelco; van Pelt, Wilfrid

    Microbial subtyping is the most common approach for Salmonella source attribution. Typically, attributions are computed using frequency-matching models like the Dutch and Danish models based on phenotyping data (serotyping, phage-typing, and antimicrobial resistance profiling). Herewith, we

  19. Effect of Carvacrol on Salmonella Saintpaul Biofilms on Stainless ...

    African Journals Online (AJOL)

    2025 ... carvacrol on S. saintpaul biofilms on stainless steel surface was evaluated on ... cultures S. saintpaul at 35 ºC were diluted 1:100 .... characteristics of biofilm formation that occur in .... aureus and Salmonella enterica serovar Typhmurium.

  20. Ionizing Radiation for the Elimination of Salmonellae from Frozen Meat

    International Nuclear Information System (INIS)

    Ley, F.J.

    1968-01-01

    The radiation resistance in frozen meat of a number of different serotypes of Salmonella has been examined. A dose of 0.65 Mrad achieves a 10 6 reduction in the numbers of the most resistant types and this dose has been shown to be effective in eliminating salmonellae from naturally contaminated meat. Some results are outlined which show that (a) Salmonella resistance is higher in frozen meat than in unfrozen meat, (b) pre-irradiation growth of the organisms in meat does not influence resistance, (c) salmonellae surviving irradiation grow at a slower rate than unirradiated organisms and appear to be unchanged in serological properties or phage type. Reference is made to wholesomeness tests carried out on irradiated meat and to the current situation on legislation in the United Kingdom controlling the irradiation of food. The identification of irradiated food is also mentioned. (author)

  1. Characterization of a Multidrug Resistant Salmonella Enterica Give

    African Journals Online (AJOL)

    Dr Olaleye

    more than 535 cases of laboratory-confirmed Salmonella infections ... Serotyping of the isolate: The isolate was sub cultured into. TSA agar and ... Electrophoresis unit (Life Technologies). Determination of .... raw minced meat. (Girardin et al.

  2. Forty Years of Salmonella enterica Dublin in People

    Centers for Disease Control (CDC) Podcasts

    2017-10-05

    Dr. Reid Harvey, a CDC epidemiologist, discusses Salmonella enterica Dublin in People.  Created: 10/5/2017 by National Center for Emerging and Zoonotic Infectious Diseases (NCEZID).   Date Released: 10/5/2017.

  3. Molecular detection of salmonella species from selected vegetables ...

    African Journals Online (AJOL)

    Molecular detection of salmonella species from selected vegetables sold in a north-central ... African Journal of Clinical and Experimental Microbiology ... of the pure isolates testing positive as being pathogenic after biochemical analysis.

  4. Tips to Reduce Your Risk of Salmonella from Eggs

    Science.gov (United States)

    ... eggs. Eat or refrigerate eggs and foods containing eggs promptly after cooking. Do not keep eggs or foods made with ... water can pull bacteria into the egg. Refrigerate eggs after collection. Cook eggs thoroughly. Raw and undercooked eggs contain Salmonella ...

  5. A retrospective study on salmonella infection in Danish broiler flocks

    DEFF Research Database (Denmark)

    Angen, Øystein; Skov, M. N.; Chriél, Mariann

    1996-01-01

    -year period from 1992 to 1993 in Denmark. The AM database contains information collected by the ante-mortem veterinarians, from the slaughterhouses, and from the salmonella examinations carried out at the National Veterinary Laboratory. The epidemiological unit was the individual broiler flock....... The salmonella status of the flock was determined by examining the caecal tonsils from 16 3-week-old chickens from each flock. This procedure would detect a salmonella-infected flock, with a probability above 95%, if the prevalence is above 20%. Furthermore, the structure and quality of the collected data have...... been evaluated. Fourteen variables were selected for analysis by multivariable logistic regression. An increased risk of salmonella infection in the broiler Becks was associated with the biggest hatcheries and feedmill, with an increasing number of houses on the farm, if the preceding flock...

  6. Biological effect of plutonium 239 on Salmonella typhimurium

    International Nuclear Information System (INIS)

    Gafieva, Z.A.; Chudin, V.A.

    1988-01-01

    Salmonella typhimurium cells were exposed in a 239 Pu citrate solution. Cell death and induction of gene mutations were an exponential fucntion of γ-radiation dose. LD 37 was 34.8 Gy; mutation doubling dose, 19 Gy

  7. Factors influencing Salmonella carcass prevalence in Danish pig abattoirs

    DEFF Research Database (Denmark)

    Freitas de Matos Baptista, Filipa; Dahl, J.; Nielsen, Liza Rosenbaum

    2010-01-01

    The Danish Salmonella Surveillance-and-Control Programme in finisher pigs includes both herd and carcass surveillance. Herd surveillance consists of serological testing of meat-juice samples and classification of herds into three Salmonella seroprevalence levels. At the abattoirs, carcass swabs...... from five pigs are collected daily and analysed as a pooled sample to evaluate the Salmonella carcass prevalence. This study aimed to investigate factors associated with Salmonella carcass prevalence in Denmark. A total of 20,196 pooled carcass swabs collected in 23 Danish abattoirs were included...... in the analysis. A multilevel logistic regression model was used taking into account the two-level data structure (abattoir, carcass pool) and adjusting the parameter estimates to the random variation at the abattoir level. Study results indicated that carcass contamination was mainly influenced...

  8. Study of Salmonella typhimurium mutagenicity assay of (E ...

    African Journals Online (AJOL)

    Study of Salmonella typhimurium mutagenicity assay of (E)-piplartine by the Ames test. AA Morandim-Giannetti, F Cotinguiba, LO Regasini, MC Frigieri, EA Varanda, A Coqueiro, MJ Kato, VS Bolzani, M Furlan ...

  9. THE GENOTOXICITY OF AMBIENT OUTDOOR AIR, A REVIEW: SALMONELLA MUTAGENICITY

    Science.gov (United States)

    The genotoxicity of ambient outdoor air, a review: Salmonella mutagenicityAbstractMutagens in urban air pollution come from anthropogenic sources (especially combustion sources) and are products of airborne chemical reactions. Bacterial mutation tests have been used ...

  10. Monitoring bacteriolytic therapy of salmonella typhimurium with optical imaging system

    International Nuclear Information System (INIS)

    Kim, Sun A; Min, Jung Joon; Moon, Sung Min; Kim, Hyun Ju; Kim, Sung Mi; Song, Ho Cheon; Choy, Hyon E.; Bom, Hee Seung

    2005-01-01

    Systemically administrated Salmonella has been studied for targeting tumor and developed as an anticancer agent. In Salmonella, because msbB gene plays role in the terminal myristoylation of lipid A and induces tumor necrosis factor a (TNF-a) -mediated septic shock, Salmonella msbB mutant strain is safe and useful for tumor-targeting therapy. Here we report that Salmonella msbB mutant strain induce onco lysis after intravenous injection in tumor bearing mice. The CT26 mouse colon cancer cells were stably transfected with firefly luciferase gene and subcutaneously implantated in Balb/C mice. After establishing subcutaneous tumor mass, we intravenously injected 1x108 cfu Salmonella msbB mutant strain or MG1655 E coli strain. Not only tumor size but also total photon flux from the tumor mass were monitored. everyday and compared among experimental groups (No treatment, Salmonella treatment, E. coli MG1655 treatment group). After intraperitoneal injection of D-Iuciferin (3 mg/animal), in vivo optical imaging for firefly luciferase was performed using cooled CCD camera. Imaging signal from Salmonella injected group were significantly lower than that of no treatment or E. coli treatment group on day 2 after injection. On day 4 after injection, imaging signal of salmonella-injected group was 43.8 or 20.7 times lower than that of no treatment or E. coli treatment group, respectively (no treatment: 2.78E+07 p/s/cm 2 /sr, Salmonella treatment: 6.35E+05 p/s/cm 2 /sr, E. coli treatment: 1.29E+07 p/s/cm 2 /sr, P<0.05). However. when we injected E. coli MG1655 into tumor bearing mice, the intensity of imaging signal was not different from no treatment group. These findings suggest that Salmonella msbB mutant strain retains its tumor-targeting properties and have therapeutical effect. Bioluminescent tumor bearing animal model was useful for assessing tumor viability after bacteriolytic therapy using Salmonella

  11. An Electrochemical DNA Biosensor for the Detection of Salmonella Using Polymeric Films and Electrochemical Labels

    Science.gov (United States)

    Diaz Serrano, Madeline

    Waterborne and foodborne diseases are one of the principal public health problems worldwide. Microorganisms are the major agents of foodborne illness: pathogens such as Salmonella, Campylobacter jejuni and Escherichia coli, and parasites such as cryptosporidium. The most popular methods to detect Salmonella are based on culture and colony counting methods, ELISA, Gel electrophoresis and the polymerase chain reaction. Conventional detection methods are laborious and time-consuming, allowing for portions of the food to be distributed, marketed, sold and eaten before the analysis is done and the problem even detected. By these reasons, the rapid, easy and portable detection of foodborne organisms will facilitate the disease treatment. Our particular interest is to develop a nucleic acid biosensor (NAB) for the detection of pathogenic microorganisms in food and water samples. In this research, we report on the development of a NAB prototype using a polymer modified electrode surface together with sequences of different lengths for the OmpC gene from Salmonella as probes and Ferrocene-labeled target (Fc-ssDNA), Ferrocene-labeled tri(ethylene glycol) (Fc-PEG) and Ruthenium-Ferrocene (Ru-Fe) bimetallic complex as an electrochemical labels. We have optimized several PS films and anchored nucleic acid sequences with different lengths at gold and carbon surfaces. Non contact mode AFM and XPS were used to monitor each step of the NAB preparation, from polymer modification to oligos hybridization (conventional design). The hybridization reaction was followed electrochemically using a Fc-ssDNA and Fc-PEG in solution taking advantage of the morphological changes generated upon hybridization. We observed a small current at the potential for the Fe oxidation without signal amplification at +296 mV vs. Ag/AgCl for the Fc-ssDNA strategy and a small current at +524 mV for the Fc-PEG strategy. The immobilization, hybridization and signal amplification of Biotin- OmpC Salmonella genes

  12. Rupture of popliteal arterial aneurysm due to salmonella infection

    International Nuclear Information System (INIS)

    Kim, Dong Hun; Oh, Hyung Woo; Kim, Dong Hyun; Byun, Joo Nam

    2006-01-01

    We report here on a case of popliteal aneurysm and rupture that occurred over a 10-day period and this was all secondary to salmonella infection. Computed tomography (CT) angiography of the extremity that was performed before and after aneurysmal rupture showed the aneurysm's rapid evolution to rupture over a short period of time. We also review the pathogenesis, clinical presentation, diagnostic approach and management of salmonella aneurysms

  13. Relationship between aerobic bacteria, salmonellae and Campylobacter on broiler carcasses.

    Science.gov (United States)

    Cason, J A; Bailey, J S; Stern, N J; Whittemore, A D; Cox, N A

    1997-07-01

    Broiler carcasses were removed from commercial processing lines immediately after defeathering, before chilling, and after chilling to determine whether any relationship exists between aerobic bacteria and the human enteropathogens salmonellae and Campylobacter. In two experiments, a whole carcass rinse procedure was used to sample 30 carcasses after defeathering, 90 carcasses before chilling, and 90 carcasses after chilling, for a total of 210 different carcasses. Aerobic bacteria and Campylobacter spp. were enumerated and the incidence of salmonellae was determined. Salmonellae and Campylobacter incidences were 20 and 94%, respectively, for all carcasses sampled. After picking, neither salmonellae-positive nor Campylobacter-positive carcasses had mean aerobic most probable number (MPN) values that were different from carcasses negative for those organisms. Immediately before chilling, aerobic and Campylobacter counts were 7.12 and 5.33 log10 cfu per carcass, respectively. Immersion chilling reduced aerobic counts by approximately 1.8 log and Campylobacter by 1.5 log, with no change in salmonellae-positive carcasses. There was no difference in aerobic or Campylobacter counts between carcasses that were positive or negative for salmonellae at any of the sampling locations, nor was any correlation found between levels of aerobic organisms and Campylobacter. Carcasses with aerobic counts above the mean or more than one standard deviation above the mean also failed to show any correlation. Discriminant analysis indicated error rates as high as 50% when numbers of aerobic bacteria were used to predict incidence of salmonellae or Campylobacter on individual carcasses. Aerobic bacteria are not suitable as index organisms for salmonellae or Campylobacter on broiler carcasses.

  14. Post-operative Salmonella surgical site infection in a dog.

    Science.gov (United States)

    Kent, Marc; Boozer, Lindsay; Glass, Eric N; Sanchez, Susan; Platt, Simon R; Freeman, Lisa M

    2017-09-01

    Following decompressive surgery for degenerative lumbosacral stenosis, a 6-year-old German shepherd dog developed a subcutaneous infection at the surgical site and discospondylitis at the lumbosacral intervertebral disc. Salmonella enterica subsp. enterica, serotype Dublin was recovered from the surgical site. Salmonella of a different serovar was isolated from a sample of the raw meat-based diet that the owner fed the dog.

  15. Inactivation of Salmonella and Listeria in ground chicken breast meat during thermal processing.

    Science.gov (United States)

    Murphy, R Y; Marks, B P; Johnson, E R; Johnson, M G

    1999-09-01

    Thermal inactivation of six Salmonella spp. and Listeria innocua was evaluated in ground chicken breast and liquid medium. Survival of Salmonella and Listeria was affected by the medium composition. Under the same thermal process condition, significantly more Salmonella and Listeria survived in chicken breast meat than in 0.1% peptone-agar solution. The thermal lethality of six tested Salmonella spp. was additive in chicken meat. Survival of Listeria in chicken meat during thermal processing was not affected by the presence of the six Salmonella spp. Sample size and shape affected the inactivation of Salmonella and Listeria in chicken meat during thermal processing.

  16. Salmonella tel-el-kebir and terrapins.

    LENUS (Irish Health Repository)

    Lynch, M

    2012-02-03

    OBJECTIVES: An outbreak of Salmonella tel-el-kebir occurring over a 6-month period is described in this report. This is the first outbreak of S. tel-el-kebir in the reported literature. METHODS: S. tel-el-kebir was isolated from human faecal samples using conventional laboratory methods. RESULTS: Eight patients had S. tel-el-kebir isolated from faeces. All patients were owners of, or in close contact with, pet terrapins. The terrapins were purchased in the same pet shop, where they were imported from America. The epidemiological link with these pets was confirmed, as S. tel-el-kebir was isolated from cloacal swabs from the terrapins, and from terrapin water. Molecular biology studies using DNA amplification fingerprinting (DAF) gave identical fingerprint patterns for all human and terrapin isolates. CONCLUSIONS: Salmonellosis associated with exotic pets is a re-emerging disease in the 1990s, and measures to reduce this are discussed.

  17. An unusual sequel to imported Salmonella zanzibar.

    Science.gov (United States)

    Johnston, W S; Munro, D; Reilly, W J; Sharp, J C

    1981-12-01

    In August, 1980 a rare serotype S. zanzibar was isolated in the North of Scotland from a man home on leave from Malaysia, whence he returned in November having been bacteriologically negative 2 months previously. In December however, S. zanzibar was isolated from a bulk milk sample taken at a nearby dairy farm. No illness occurred among milking cows which had been brought inside from pasture in mid-October. Since 1972 a variety of different salmonella serotypes had been identified in cattle, milk and other samples at this farm, with seagulls being implicated as the vector transmitting infection from the sewage of a local town on to farmland and an adjacent loch. Although water from this source has not been used in recent years for drinking by cattle, it is utilized for washing floors within the dairy premises. Since 1979, following an outbreak affecting consumers, all milk produced at the farm has been pasteurized.

  18. Isolation of Salmonellae from Foods Samples

    Science.gov (United States)

    Taylor, Welton I.; Silliker, John H.

    1961-01-01

    A comparison of various methods of enhancing frequency of Salmonella isolations revealed that inoculation of a second enrichment broth, with culture from the first, was no improvement over the single direct enrichment method. It was inferior to centrifugation. Selenite was observed to produce more positive isolations at 48 hr than at 24. No change occurred in tetrathionate. Reconstitution of dried albumen with water produced a significant increase in isolations over direct inoculation of enrichment broth in the case of tetrathionate but not selenite broth. Pre-enrichment in lactose broth before inoculation of enrichment media was vastly superior to reconstitution in water for both enrichment broths. A comparison of results obtained using dulcitol, mannitol, lactose and carbohydrate-free purple broths in pre-enrichment indicated that the carbohydrate added was immaterial. PMID:13920002

  19. Experimental Salmonella typhimurium infections in rats. I

    DEFF Research Database (Denmark)

    Hougen, H P; Jensen, E T; Klausen, B

    1989-01-01

    The course of experimentally induced Salmonella typhimurium infection was studied in three groups of inbred LEW rats: homozygous +/+, athymic rnu/rnu and isogeneic thymus-grafted rnu/rnu rats. In the first experiment the animals were inoculated intraperitoneally with 10(8) bacteria and all animals...... became severely septicemic and died within a week of inoculation, irrespective of presence or absence of thymus. In the second experiment the animals were inoculated with 10(6) bacteria, and both euthymic and thymus-grafted animals responded with high titres of anti bacterial antibodies while these were...... very low in the athymic nude animals. Polyclonal antibody production was only observed in the euthymic animals and only regarding IgG. Athymic rats were not able to clear the infection, while the thymus-grafted animals reacted like euthymic rats: Very few animals housed the bacteria four weeks after...

  20. Serovars of Salmonella from captive reptiles

    DEFF Research Database (Denmark)

    Pedersen, Karl; Lassen-Nielsen, Anne Marie; Nordentoft, Steen

    2009-01-01

    The distribution on serovars of 60 Salmonella isolates from reptiles kept in captivity in Denmark during the period 1995–2006 was investigated. The isolates were all recovered from clinical specimens submitted to the National Veterinary Institute. A majority of the samples were from reptiles...... in zoological gardens or similar, while a minor number was from reptiles kept in private homes. A total of 43 serovars were detected, most of them being what is usually called exotic serotypes, and many not having a trivial name, while a few isolates belonged to well-known human pathogenic serovars, such as S....... Enteritidis, S. Typhimurium, S. Bovismorbificans. One isolate was rough and two were non-typeable. Isolates from turtles belonged to the subspecies enterica, while many isolates from both sauria and snakes belonged to other subspecies. The findings underline the potential zoonotic risk by handling reptiles...