| engineered salmonella allows real-time heterologous gene expression monitoring within infected zebrafish embryos. | microbial host-pathogen interactions have been traditionally well studied at genetic and physiological levels, but cell-resolution analyses have been particularly scarce. this has been especially remarkable for intracellular parasites for two major reasons: first, the inherent loss of bacteria traceability once infects its hosts; second and more important, the limited availability of genetic tools that allow a tight regulated expression of bacterial virulence genes once inside the host tissues. ... | 2011 | 22178780 |
| survival and heat resistance of salmonella enterica and escherichia coli o157:h7 in peanut butter. | significant differences (p < 0.05) were found between the survival rates of salmonella enterica and escherichia coli o157:h7 in peanut butter with different formulations and water activity. high carbohydrate content in peanut butter and low incubation temperature resulted in higher levels of bacterial survival during storage but lower levels of bacterial resistance to heat treatment. | 2011 | 21965404 |
| evolution of salmonella nomenclature: a critical note. | salmonellae are widely distributed but nomenclaturally controversial pathogens of both humans and animals. despite elaborate studies, much still remain to be discovered about these organisms. although salmonella nomenclature has proved to be rather complex, in 2005, salmonella enterica finally gained official approval as the type species of the genus salmonella. in addition, one other species has been approved and recognised in the genus salmonella, namely, salmonella bongori. new serovars (sero ... | 2011 | 22052214 |
| developing next generation antimicrobials by intercepting ai-2 mediated quorum sensing. | bacteria have been evolving antibiotic resistance since their discovery in the early twentieth century. most new antibiotics are derivatives of older generations and there are now bacteria that are virtually resistant to almost all antibiotics. this poses a global threat to human health and has been classified as a clinical "super-challenge", which has necessitated research into new antimicrobials that inhibit bacterial virulence while minimizing selective pressures that lead to the emergence of ... | 2011 | 22112397 |
| screening, phylogenetic analysis and antibiotic sensitivity pattern of salmonella enterica serovar typhi isolates from typhoid asymptomatic carriers. | to isolate the salmonella enterica serovar typhi (s. typhi) from asymptomatic typhoid carriers in the local population. to assess the antibiotic sensitivity and resistant pattern of s. typhi isolates against viable antibiotics and phylogenetic analysis of s. typhi isolates on the basis of 16s rdna gene. | 2011 | 22014730 |
| the stepone real-time polymerase chain reaction detection of salmonella sp., salmonella enterica ser. typhimurium and enteritidis in milk and meat. | the aim of this study was to follow contamination of ready to eat milk and meat products with salmonella spp. by using the stepone real-time polymerase chain reaction (pcr). classical microbiological methods for detection of foodborne bacteria involve the use of pre-enrichment and/or specific enrichment, following isolation of bacteria in solid media and the final confirmation by biochemical and/or serological tests. we used the prepseq rapid spin sample preparation kit for isolation of dna and ... | 2011 | 21879831 |
| evaluation of an immunochromatographic assay for rapid detection of salmonella enterica serovars typhimurium and enteritidis. | an immunochromatographic assay was developed to detect salmonella enterica serovars typhimurium and enteritidis in a single strip. the assay was constructed in the form of a sandwich, using 2 specific anti-s. typhimurium and anti-s. enteritidis antibodies immobilized on a nitrocellulose membrane at separated test lines, while the other specific antibody to salmonella spp. was conjugated with gold nanoparticles. the test strips can immediately detect s. typhimurium and s. enteritidis specifically ... | 2011 | 21908327 |
| death receptor 3 is essential for generating optimal protective cd4(+) t-cell immunity against salmonella. | the tnf receptor superfamily member death receptor 3 (dr3) exacerbates th2 and th17-mediated inflammatory and autoimmune conditions, yet no role in host defence has been reported. here we examined the role of dr3 during infection with salmonella enterica serovar typhimurium. infection resulted in protracted expression of the dr3 ligand tl1a but not the related tnf superfamily proteins ox40l or cd30l. tl1a expression was localized to splenic f4/80(+) macrophages where s. enterica typhimurium rep ... | 2011 | 22120936 |
| identification of tumor-specific salmonella typhimurium promoters and their regulatory logic. | conventional cancer therapies are often limited in effectiveness and exhibit strong side effects. therefore, alternative therapeutic strategies are demanded. the employment of tumor-colonizing bacteria that exert anticancer effects is such a novel approach that attracts increasing attention. for instance, salmonella enterica serovar typhimurium has been used in many animal tumor models as well as in first clinical studies. these bacteria exhibit inherent tumoricidal effects. in addition, they ca ... | 2011 | 22140114 |
| leaching of cryptosporidium parvum oocysts, escherichia coli, and a salmonella enterica serovar typhimurium bacteriophage through intact soil cores following surface application and injection of slurry. | increasing amounts of livestock manure are being applied to agricultural soil, but it is unknown to what extent this may be associated with contamination of aquatic recipients and groundwater if microorganisms are transported through the soil under natural weather conditions. the objective of this study was therefore to evaluate how injection and surface application of pig slurry on intact sandy clay loam soil cores influenced the leaching of salmonella enterica serovar typhimurium bacteriophage ... | 2011 | 21948848 |
| direct feeding of microencapsulated bacteriophages to reduce salmonella colonization in pigs. | salmonella shedding often increases in pigs after transportation and/or lairage. we previously showed that administering anti-salmonella bacteriophages to pigs by gavage significantly reduced salmonella colonization when the pigs were exposed to a salmonella-contaminated holding pen. here we tested whether a microencapsulated phage cocktail would remain effective if the treatment was administered to pigs in the feed. pigs (n=21) were randomly placed into three groups: feed, gavage, and control. ... | 2011 | 21854261 |
| integrating global regulatory input into the salmonella pathogenicity island 1 type iii secretion system. | salmonella enterica serovar typhimurium uses the salmonella pathogenicity island 1 (spi1) type iii secretion system to induce inflammatory diarrhea and bacterial uptake into intestinal epithelial cells. the expression of hila, encoding the transcriptional activator of the spi1 structural genes, is directly controlled by three arac-like regulators, hild, hilc, and rtsa, each of which can activate the hild, hilc, rtsa, and hila genes, forming a complex feed-forward regulatory loop. a large number ... | 2011 | 22021388 |
| salmonella enterica in swine production: assessing the association between amplified fragment length polymorphism and epidemiological units of concern. | the aims of this study were to determine the ability of amplified fragment length polymorphism (aflp) to differentiate salmonella isolates from different units of swine production and to demonstrate the relatedness of salmonella between farms and abattoirs by aflp. twenty-four farms in the midwestern united states were visited four times from 2006 to 2009. at each farm or abattoir visit, 30 fecal samples or 30 mesenteric lymph nodes were collected, respectively. a total of 220 salmonella isolate ... | 2011 | 21948822 |
| comparative proteomic analysis of salmonella enterica serovars enteritidis, typhimurium and gallinarum. | salmonella enterica includes several related serovars which have different host ranges and cause diseases of different severities. however, their pathogenic potential is unknown, and it is not clear what mechanisms are activated or inhibited during adaptation to a specific host environment. some proteins are involved in the mechanism of pathogenicity at a molecular level and provide the functional aspects that create the diverse phenotypes. to compare proteomic analyses of the total proteins of ... | 2011 | 21997235 |
| fate of pathogens in a simulated bioreduction system for livestock carcasses. | the eu animal by-products regulations generated the need for novel methods of storage and disposal of dead livestock. bioreduction prior to rendering or incineration has been proposed as a practical and potentially cost-effective method; however, its biosecurity characteristics need to be elucidated. to address this, salmonella enterica (serovars senftenberg and poona), enterococcus faecalis, campylobacter jejuni, campylobacter coli and a lux-marked strain of escherichia coli o157 were inoculate ... | 2011 | 22119516 |
| the role of rama on the development of ciprofloxacin resistance in salmonella enterica serovar typhimurium. | active efflux pump is a primary fluoroquinolone resistant mechanism of clinical isolates of salmonella enterica serovar typhimurium. rama is an essential element in producing multidrug resistant (mdr) s. enterica serovar typhimurium. the aim of the present study was to elucidate the roles of rama on the development of ciprofloxacin, the first choice for the treatment of salmonellosis, resistance in s. enterica serovar typhimurium. spontaneous mutants were selected via several passages of s. ente ... | 2011 | 21858134 |
| methodologies for salmonella enterica subsp. enterica subtyping: gold standards and alternatives. | for more than 80 years, subtyping of salmonella enterica has been routinely performed by serotyping, a method in which surface antigens are identified based on agglutination reactions with specific antibodies. the serotyping scheme, which is continuously updated as new serovars are discovered, has generated over time a data set of the utmost significance, allowing long-term epidemiological surveillance of salmonella in the food chain and in public health control. conceptually, serotyping provide ... | 2011 | 21856826 |
| typhoid fever: "you can't hit what you can't see" | the host restricts dissemination of invasive enteric pathogens, such as non-typhoidal salmonella serovars, by mounting acute inflammatory responses characterized by the recruitment of neutrophils. however, some enteric pathogens, such as salmonella enterica serovar typhi (s. typhi), can bypass these defenses and cause an invasive bloodstream infection known as typhoid fever. recent studies on virulence mechanisms of s. typhi suggest that tight regulation of virulence gene expression during the t ... | 2012 | 22156762 |
| use of multilocus variable-number tandem repeat analysis in molecular subtyping of salmonella enterica serovar typhi isolates. | we evaluated 11 variable number tandem repeat (vntr) markers for the epidemiological investigation of salmonella enterica serovar typhi (s. typhi) infection and compared the results to those obtained by pfge. pfge, using one or two restriction enzymes (xbai and blni), was insufficient to differentiate between some isolates that were epidemiologically unlinked. multilocus variable-number tandem repeat analysis (mlva)-8, based on analysis of the eight most variable vntrs, displayed a high level of ... | 2011 | 21997873 |
| innate immune control of salmonella enterica serovar typhimurium: mechanisms contributing to combating systemic salmonella infection. | infections with salmonella enterica serovars remain a serious problem worldwide. while serovar typhi causes significant morbidity and mortality that is restricted to humans, serovar typhimurium causes gastroenteritidis in humans and can also infect other animals. as mice with the susceptible nramp1 locus get systemic infection with serovar typhimurium, murine infection models using this serovar have been widely used to decipher the immune mechanisms required to survive systemic salmonella infect ... | 2011 | 21912097 |
| Extended-spectrum ß-lactamases in German isolates belonging to the emerging monophasic Salmonella enterica subsp. enterica serovar Typhimurium 4,[5],12:i:- European clone. | | 2011 | 22058374 |
| gaussia princeps luciferase as a reporter for transcriptional activity, protein secretion, and protein-protein interactions in salmonella enterica serovar typhimurium. | gaussia princeps luciferase (gluc) is widely used as a reporter in eukaryotes, but data about its applicability in bacteria are very limited. here we show that a codon-optimized gluc gene can be efficiently expressed in salmonella enterica serovar typhimurium. to test different gluc variants as transcriptional reporters, we used the siia promoter of salmonella pathogenicity island 4 (spi-4) driving expression of either an episomal or a chromosomally integrated gluc gene. most reliable results we ... | 2012 | 22020521 |
| expansion of tfh-like cells during chronic salmonella exposure mediates the generation of autoimmune hypergammaglobulinemia in myd88-deficient mice. | the role of tlr signaling in linking the innate and adaptive immune systems has been a controversial issue that remains to be solved. here, we determined whether myd88-dependent tlr signals are required for the generation of b-cell responses during chronic salmonella infection. oral administration of recombinant attenuated salmonella enterica serovar typhimurium vaccine (rasv) strain in myd88(-/-) mice resulted in chronic infection. infection was accompanied by enlarged germinal centers and hyp ... | 2011 | 22105301 |
| transcriptional regulation of sdia by camp-receptor protein, leuo, and environmental signals in salmonella enterica serovar typhimurium. | the sdia gene encodes for a luxr-type transcription factor, which is active when bound to n-acyl homoserine lactones (ahls). because salmonella enterica serovar typhimurium does not produce ahls, sdia senses signals produced by other organisms. sdia is not expressed constitutively, and response is limited to conditions in which elevated expression occurs, but little is known about the regulation of sdia expression. here we map the sdia promoter and define several regulators that directly or in ... | 2011 | 22149171 |
| evaluation of salmonella movement through the gut of the lesser mealworm, alphitobius diaperinus (coleoptera: tenebrionidae). | abstract aims: the lesser mealworm, alphitobius diaperinus is an important poultry pest prevalent during production that is capable of vectoring pathogens. this study was undertaken to determine the gut transit time of salmonella for biosecurity risk analysis of pathogen dispersal into the environment. methods: adult and larval a. diaperinus were exposed to two concentrations of a fluorescently labeled salmonella enterica for 15, 30, and 60 min time periods then externally disinfected to evalu ... | 2011 | 22022817 |
| a whole-genome single nucleotide polymorphism-based approach to trace and identify outbreaks linked to a common salmonella enterica subsp. enterica serovar montevideo pulsed-field gel electrophoresis type. | in this study, we report a whole-genome single nucleotide polymorphism (snp)-based evolutionary approach to study the epidemiology of a multistate outbreak of salmonella enterica subsp. enterica serovar montevideo. this outbreak included 272 cases that occurred in 44 states between july 2009 and april 2010. a case-control study linked the consumption of salami made with contaminated black and red pepper to the outbreak. we sequenced, on the solid system, 47 isolates with xbai pfge pattern jixx01 ... | 2011 | 22003026 |
| protective effect by bacillus smithii tbmi12 spores of salmonella serotype enteritidis in mice. | avoiding food-borne diseases by competitive exclusion agents is a proactive strategy. in the current paper, we report the use of bacillus smithii tbmi12 spores as potential competitive exclusion agents. one group of mice was predosed for three successive days with 10(8) colony forming units of b. smithii tbmi12 spores followed by inoculation with 10(6) colony forming units of wild-type salmonella enterica serotype enteritidis cells. microbial plate counts of the animals' livers and spleens showe ... | 2010 | 21840796 |
| use of an avirulent live salmonella choleraesuis vaccine to reduce the prevalence of salmonella carrier pigs at slaughter. | this study evaluated the use of an avirulent live salmonella choleraesuis vaccine to reduce the seroprevalence and number of salmonella carrier pigs at slaughter. seven batches of 500 pigs were included in each of the two study groups: the vaccinated group (vg) that was orally vaccinated and the control group (cg) that received a placebo on the first day of life. the groups were managed in a three-site system and followed up from birth to slaughter. blood samples (n=378) were collected from each ... | 2011 | 21949083 |
| complete genome sequence of salmonella bacteriophage spn3us. | salmonella bacteriophage spn3us was isolated from a chicken fecal sample. it is a virulent phage belonging to the myoviridae family and showing effective inhibition of salmonella enterica and a few escherichia coli o157:h7 strains. here we announce the completely sequenced first genome of a salmonella phage using flagella as receptors. it is the largest genome among salmonella phages sequenced to date, and major findings from its annotation are described. | 2011 | 22106383 |
| chicken feet bacteriological quality at 4 steps of technological processing. | the production of chicken feet is primarily intended for foreign markets, and there is still no specific legislation in brazil that determines the quality standard of these products. the bacteriological quality of chicken feet was evaluated as a product for human consumption at different steps of the technological processes. eighty broiler feet from 20 lots at 4 steps of processing were collected for quantitative analysis, total count of aerobic mesophilic bacteria, and determining the most prob ... | 2011 | 22080026 |
| Trichinella spiralis: intranasal immunization with attenuated Salmonella enterica carrying a gp43 antigen-derived 30mer epitope elicits protection in BALB/c mice. | Trichinellosis is a public health problem and is considered an emergent/re-emergent disease in various countries. The etiological agent of trichinellosis is the nematode Trichinella, which infects domestic animals such as pigs and horses, as well as wild animals and humans. A veterinary vaccine could be an option to control the disease in domestic animals. Although several vaccine candidates have shown promising results, a vaccine against trichinellosis remains unavailable to date. Attenuated Sa ... | 2011 | 21907709 |
| characterization of a vii-like phage specific to escherichia coli o157:h7. | phage vb_ecom_cba120 (cba120), isolated against escherichia coli o157:h7 from a cattle feedlot, is morphologically very similar to the classic phage vii of salmonella enterica serovar typhi. until recently, little was known genetically or physiologically about the vii-like phages, and none targeting e. coli have been described in the literature. the genome of cba120 has been fully sequenced and is highly similar to those of both vii and the shigella phage ag3. the core set of structural and repl ... | 2011 | 21899740 |
| Genetic response of Salmonella enterica serotype Enteritidis to thioridazine rendering the organism resistant to the agent. | Thioridazine (TZ)-induced accumulation of the universal efflux pump substrate ethidium bromide and its subsequent efflux by Salmonella strains with various degrees of overexpressed efflux pumps takes place automatically at pH 7.4, is independent of a metabolic source, is not affected by a proton ionophore and is precluded by palmitic acid. Salmonella enterica serotype Enteritidis cultured in medium containing increasing concentrations of TZ does not grow during the first 6-8h, after which time i ... | 2012 | 21982147 |
| Production of a conjugate vaccine for Salmonella enterica serovar Typhi from Citrobacter Vi. | A conjugate vaccine for Salmonella enterica serovar Typhi was produced by chemically linking Vi, purified from Citrobacter, to the non-toxic mutant diphtheria toxin CRM(197) via an adipic dihydrazide spacer using N-(3-Dimethylaminopropyl)-N'-ethylcarbodiimide coupling chemistry. The polysaccharide purification process was developed based on Vi precipitation from culture supernatant with cetyl trimethylammonium bromide (CTAB), solubilization of the CTA-polysaccharide salt with ethanol followed by ... | 2011 | 22172503 |
| Antimicrobial resistance and class I integrons in Salmonella enterica isolates from wild boars and Bísaro pigs. | The antibiotic resistance phenotype and genotype and the integron type were characterized in 58 Salmonella enterica isolates recovered from Bísaro pigs and wild boars (20 S. Typhimurium, 17 S. Rissen, 14 S. Enteritidis and 7 S. Havana). Most S. Typhimurium isolates (15/20 of Bísaro pigs and wild boars) showed ampicillin, chloramphenicol, streptomycin, tetracycline, sulfonamide, and amoxicillin-clavulanic acid resistances. Of the 17 S. Rissen isolates of both origins, 13 were resistant to ampicil ... | 2011 | 22015698 |
| salmonella enterica in pinnipeds, chile. | | 2011 | 22172111 |
| diversity of salmonella enterica serovar derby isolated from pig, pork and humans in germany. | salmonella enterica serovar derby (s. derby) is one of the most prevalent serovars in pigs in europe and in the u.s. and ranks among the 10 most frequently isolated serovars in humans. therefore, a set of 82 epidemiologically unrelated s. derby strains isolated between 2006 and 2008 from pigs, pork and humans in germany was selected and investigated in respect to the transmission of clonal groups of the serovar along the food chain. various phenotypic and genotypic methods were applied and the p ... | 2011 | 21917347 |
| Involvement of red blood cells in the regulation of leukotriene synthesis in polymorphonuclear leucocytes upon interaction with Salmonella Typhimurium. | Leukotriene (LT) B4 is the primary eicosanoid product of polymorphonuclear leucocytes (PMNLs). We studied LT synthesis in PMNLs upon interaction with Salmonella enterica serovar Typhimurium. Human PMNLs exposed to Salmonella produced LTs; mostly LTB4 and ?-hydroxy-LTB4. Opsonization with normal serum increased the capacity of S. Typhimurium to induce LT synthesis in PMNLs. Addition of red blood cells (RBCs) alone did not activate LT synthesis in PMNLs but did further increase the Salmonella-indu ... | 2011 | 21851422 |
| TBK1 mediates crosstalk between the innate immune response and autophagy. | The autophagic pathway participates in many physiological and pathophysiological processes. Autophagy plays an important role, as part of the innate immune response, in the first line of defense against intruding pathogens. Recognition of pathogens by the autophagic machinery is mainly mediated by autophagic adaptors, proteins that simultaneously interact with specific cargos and components of the autophagic machinery. However, the exact mechanisms and signaling pathways regulating this step are ... | 2011 | 21868362 |
| Study of the chemical composition and antimicrobial activities of ethanolic extracts from roots of Scutellaria baicalensis Georgi. | Scutellaria baicalensis Georgi (SBG), commonly named Huangqin, showed strong in vitro antimicrobial effects. However, limited research is available to systematically evaluate the effects of extraction methods on the phytochemical composition of SBG and its associated antimicrobial effects. In addition, limited studies have tested SBG as a natural antimicrobial agent on fresh produce such as tomatoes. In the current study, powered roots of SBG were extracted with 60, 80, and 100% ethanol, and th ... | 2011 | 21866919 |
| Identification of transferable DHA-1 type AmpC beta-lactamases and two mutations in quinolone resistance-determining regions in Salmonella enterica Thompson. | Human illnesses caused by Salmonella species often require antibiotic treatment, and antibiotic resistance for Salmonella species is conferred through multiple mechanisms. Salmonella enterica Thompson, a pathogen commonly infecting poultry, causes human infection following food-borne transmission, and mechanisms of antibiotic resistance for this pathogen have not been well characterized. We isolated Salmonella enterica Thompson (Salmonella enterica Thompson NC24) from the stool of a 3-year-old p ... | 2011 | 22096136 |
| characterization of salmonella enterica serovar stanley isolates; a serovar endemic to asia and associated with travel. | salmonella enterica serovar stanley (s. stanley) is a common serovar in southeast asia; and was in the years 2002-2007, the second most common serovar implicated in human salmonellosis in thailand. in contrast, this serovar is relatively uncommon in europe.the objective of this study was to characterize a collection of s. stanley strains isolated from thai (n=62), danish (n=39) and french patients (n=24) to gain a broader understanding of the genetic diversity, population dynamics, and susceptib ... | 2011 | 22205822 |
| phenotype, virulence and immunogenicity of edwardsiella ictaluri cyclic adenosine 3',5'-monophosphate receptor protein (crp) mutants in catfish host. | edwardsiella ictaluri is an enterobacteriaceae that causes lethal enteric septicemia in catfish. being a mucosal facultative intracellular pathogen, this bacterium is an excellent candidate to develop immersion-oral live attenuated vaccines for the catfish aquaculture industry. deletion of the cyclic 3',5'-adenosine monophosphate (camp) receptor protein (crp) gene in several enterobacteriaceae has been utilized in live attenuated vaccines for mammals and birds. here we characterize the crp gene ... | 2011 | 22015784 |
| Prevalence of Salmonella enterica and the hygienic indicator Escherichia coli in raw meat at markets in Ouagadougou, Burkina Faso. | This study investigated the hygienic status and prevalence of Salmonella and Escherichia coli in retail meat sold at open markets in Ouagadougou, Burkina Faso. A total of 150 samples of beef meat (n = 45), beef intestine (n = 45), mutton (n = 30), and chicken (n = 30) were collected from four local markets for investigation. The prevalence of Salmonella enterica subsp. enterica was 9.3%, and six serotypes, all previously unreported in Burkina Faso, were identified: Derby, Tilene, Hato, Bredeney, ... | 2011 | 21902926 |
| Description of a 2,683-Base-Pair Plasmid Containing qnrD in Two Providencia rettgeri Isolates. | qnr genes are plasmid-mediated quinolone resistance genes mainly harbored on large conjugative multiresistant plasmids. The qnrD gene was recently observed in Salmonella enterica on a small nonconjugative plasmid (p2007057). We describe two strains of Providencia rettgeri harboring qnrD on nonconjugative plasmids. The plasmids were 99% identical, with 2,683 bp and four open reading frames, including qnrD, but exhibited only 53% identity with the plasmid found in S. enterica. | 2012 | 21986831 |
| Breast Abscess in a Man Due to Salmonella enterica Serotype Enteritidis. | Nontyphoidal salmonellae can cause breast infection only exceptionally. A case of breast abscess in a 70-year-old man due to Salmonella enterica serotype Enteritidis (Salmonella Enteritidis) is reported. The infection was successfully treated with a combination of surgical and antibiotic treatment. | 2012 | 22031702 |
| Bacterial rejuvenation: lag phase is a distinct growth phase that prepares bacteria for exponential growth and involves transient metal accumulation. | Lag phase represents the earliest and most poorly understood stage of the bacterial growth cycle. We developed a reproducible experimental system and conducted functional genomic and physiological analyses of a 2 hour lag phase in Salmonella enterica serovar Typhimurium. Adaptation began within four minutes of inoculation into fresh LB media, with the transient expression of genes involved in phosphate uptake. The main lag phase transcriptional programme initiated at twenty minutes with the up-r ... | 2011 | 22139505 |
| meta-analytic approach to the accurate prediction of secreted virulence effectors in gram-negative bacteria. | many pathogens use a type iii secretion system to translocate virulence proteins (called effectors) in order to adapt to the host environment. to date, many prediction tools for effector identification have been developed. however, these tools are insufficiently accurate for producing a list of putative effectors that can be applied directly for labor-intensive experimental verification. this also suggests that important features of effectors have yet to be fully characterized. | 2011 | 22078363 |
| characterization of class i integrons among salmonella enterica serovar enteritidis isolated from humans and poultry. | a total of 84 salmonella enterica serovar enteritidis (s. enteritidis) isolates, 42 of human and 42 of poultry origin, were characterized for antimicrobial resistance patterns and class i integrons. among them, 58 (69%) s. enteritidis were multidrug-resistant (mdr) and showed resistance to two or more antibiotic classes. by pcr assays and dna sequencing, 50 (59.5%) s. enteritidis isolates were found to carry class i integrons. amplification of internal variable regions of class i integrons revea ... | 2011 | 22066813 |
| Deletion of yncD gene in Salmonella enterica subsp. enterica serovar Typhi leads to attenuation in mouse model. | TonB-dependent transporters (TBDTs) are bacterial outer membrane proteins that usually involve in uptake of certain key nutrients, for example, iron. In the genome of Salmonella enterica subsp. enterica serovar Typhi, yncD gene encodes a putative TBDT and was identified as an in vivo induced antigen recently. In the present study, a yncD-deleted mutant was constructed to evaluate the role of the yncD gene in virulence. Our results showed that the mutant is attenuated to a mouse model by intraper ... | 2011 | 22150228 |
| Differential gene expression of antimicrobial peptides ß defensins in the gastrointestinal tract of Salmonella serovar Pullorum infected broiler chickens. | Salmonella enterica serovar Pullorum causes substantial mortality in chicks as well as results in persistent infection and vertical transmission in layer birds. An effective innate immune response in the early stages of infection could reduce bacterial colonization and mortality in chicks and persistency of infection in later stages. ß Defensins (AvBDs) are now considered as one of the key components of innate immunity in avian species. In the present study, we quantified the mRNA expression lev ... | 2011 | 22170093 |
| Use of bioinformatic SNP predictions in differentially expressed genes to find SNPs associated with Salmonella colonization in swine. | Asymptomatic Salmonella-carrier pigs present a major problem in preharvest food safety, with a recent survey indicating >50% of swine herds in the United States have Salmonella-positive animals. Salmonella-carrier pigs serve as a reservoir for contamination of neighbouring pigs, abattoir pens and pork products. In addition, fresh produce as well as water can be contaminated with Salmonella from manure used as fertilizer. Control of Salmonella at the farm level could be through genetic improvemen ... | 2011 | 21906181 |
| change in antimicrobial resistance pattern in salmonella enterica serovar typhimurium isolates detected in a beef cattle farm. | multidrug-resistant salmonella enterica serovar typhimurium (s. typhimurium) isolates with four different antimicrobial resistance patterns obtained from a beef cattle farm were characterized to determine their clonality. macrorestriction analysis of genomic dna revealed that these four isolates are closely related to each other and can be classified as a newly emerged pulsed-field gel electrophoresis type among cattle: cluster vii. three of the four isolates showed resistance to extended-spectr ... | 2011 | 21869573 |
| hydrogen-stimulated carbon acquisition and conservation in salmonella enterica serovar typhimurium. | salmonella enterica serovar typhimurium can utilize molecular hydrogen for growth and amino acid transport during anaerobic growth. via microarray we identified h(2) gas-affected gene expression changes in salmonella. the addition of h(2) caused altered expression of 597 genes, of which 176 genes were upregulated and 421 were downregulated. the significantly h(2)-upregulated genes include those that encode proteins involved in the transport of iron, manganese, amino acids, nucleosides, and sugar ... | 2011 | 21856852 |
| [surveillance of nalidixic acid-resistant and extended-spectrum beta-lactamase-producing salmonella spp. isolated from human feces]. | nalidixic acid (na)-resistant and extended-spectrum beta-lactamase (esbl)-producing salmonella sp. isolates from human specimens are associated with clinical failure or delayed response in subjects treated with fluoroquinolone or third-generation cephalosporins. we studied drug susceptibility in 604 salmonella enterica isolates from human feces in 2007. of these, 39 (6.5%) were resistat to na. of these, 46% were resistant to two or more drugs and 2% susceptible to na were resistant to multiple d ... | 2011 | 21861438 |
| increased persistence of salmonella enterica serovar typhi in the presence of acanthamoeba castellanii. | salmonella enterica serovar typhi (s. typhi) is the etiological agent of the systemic disease typhoid fever. transmission occurs via ingestion of contaminated food or water. s. typhi is specific to humans, and no animal or environmental reservoirs are known. as the free-living amoeba acanthamoeba castellanii is an environmental host for many pathogenic bacteria, this study investigates interactions between s. typhi and a. castellanii by using cocultures. growth of both organisms was estimated by ... | 2011 | 21926221 |
| salmonella persistence and transmission strategies. | host-adapted strains of salmonella enterica cause systemic infections and have the ability to persist systemically for long periods of time and pose significant public-health problems. multidrug-resistant salmonella enteric serovar typhi (s. typhi) and non-typhoidal salmonella (nts) are on the increase, and are often associated with hiv infection. chronically infected hosts are often asymptomatic and transmit disease to naïve hosts via fecal shedding of bacteria, thereby serving as a critical re ... | 2011 | 22137596 |
| multi-locus variable-number tandem repeat profiling of salmonella enterica serovar typhi isolates from blood cultures and gallbladder specimens from makassar, south-sulawesi, indonesia. | 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 complicate disease prevention and control. | 2011 | 21949819 |
| expansion of paneth cell population in response to enteric salmonella enterica serovar typhimurium infection. | paneth cells residing at the base of the small intestinal crypts contribute to the mucosal intestinal first line defense by secreting granules filled with antimicrobial polypeptides including lysozyme. these cells derive from the columnar intestinal stem cell located at position 0 and the transit amplifying cell located at position +4 in the crypts. we have previously shown that salmonella enterica serovar typhimurium (st), a leading cause of gastrointestinal infections in humans, effects an ove ... | 2012 | 22006567 |
| salmonella enterica as a vaccine carrier. | salmonella enterica is an invasive, facultative intracellular gastrointestinal pathogen causing human diseases such as gastroenteritis and typhoid fever. virulence-attenuated strains of this pathogen have interesting capacities for the generation of live vaccines. attenuated live typhoidal and nontyphoidal salmonella strains can be used for vaccination against salmonella infections and to target tumor tissue. such strains may also serve as live carriers for the development of vaccination strateg ... | 2012 | 22191450 |
| interaction of concanavalin a with bacterial lipopolysaccharides in agarose gel. | binding of fluorescein isothiocyanate-labeled concanavalin a to a series of molecular species of lipopolysaccharide (lps), purified from pathogenic bacteria, was studied via agarose gel precipitation experiments and the results were compared with available structural data.the lps species could be divided into cona-reactive and non-reactive ones. reactivity resided in the o-specific chain of lps, and binding to the lipid a or core moieties of lps could not be demonstrated by the present methods. ... | 2011 | 21983321 |
| cell-associated flagella enhance the protection conferred by mucosally-administered attenuated salmonella paratyphi a vaccines. | antibiotic-resistant salmonella enterica serovar paratyphi a, the agent of paratyphoid a fever, poses an emerging public health dilemma in endemic areas of asia and among travelers, as there is no licensed vaccine. integral to our efforts to develop a s. paratyphi a vaccine, we addressed the role of flagella as a potential protective antigen by comparing cell-associated flagella with exported flagellin subunits expressed by attenuated strains. | 2011 | 22069504 |
| evidence of significant synergism between antibiotics and the antipsychotic, antimicrobial drug flupenthixol. | previously, the antipsychotic, non-antibiotic compound flupenthixol dihydrochloride (fp) was shown to exhibit distinct in vitro antibacterial activity against gram-positive and gram-negative bacteria and to significantly protect swiss albino mice challenged with a known mouse virulent salmonella. the present study was designed to ascertain whether this drug could efficiently augment the action of an antibiotic or a non-antibiotic when tested in combination. a total of 12 bacterial strains belong ... | 2011 | 21997771 |
| enterobacterial common antigen mutants of salmonella enterica serovar typhimurium establish a persistent infection and provide protection against subsequent lethal challenge. | infection with salmonella spp. is a significant source of disease globally. a substantial proportion of these infections are caused by salmonella enterica serovar typhimurium. here, we characterize the role of the enterobacterial common antigen (eca), a surface glycolipid ubiquitous among enteric bacteria, in s. typhimurium pathogenesis. construction of a defined mutation in the udp-n-acetylglucosamine-1-phosphate transferase gene, weca, in two clinically relevant strains of s. typhimurium, tml ... | 2012 | 22025511 |
| competition and resilience between founder and introduced bacteria in the caenorhabditis elegans gut. | the microbial communities that reside within the intestinal tract in vertebrates are complex and dynamic. in this report, we establish the utility of c. elegans as a model system for identifying the factors that contribute to bacterial persistence and for host control of gut luminal populations. we found that for n2 worms grown on mixed lawns of bacteria, salmonella substantially out-competed e. coli even when e. coli was initially present at 100-fold higher concentrations. to address whether in ... | 2011 | 22184417 |
| in vivo expression of salmonella enterica serotype typhi genes in the blood of patients with typhoid fever in bangladesh. | salmonella enterica serotype typhi is the cause of typhoid fever. it is a human-restricted pathogen, and few data exist on s. typhi gene expression in humans. | 2011 | 22180799 |
| The TCA cycle is not required for selection or survival of multidrug-resistant Salmonella. | OBJECTIVES: The initial aim of this study was to use a systems biology approach to analyse a ciprofloxacin-selected multidrug-resistant (MDR) Salmonella enterica serotype Typhimurium, L664. METHODS: The whole genome sequence and transcriptome of L664 were analysed. Site-directed mutagenesis to recreate each mutation was carried out, followed by phenotypic characterization and mutation frequency analysis. As a mutation in the TCA cycle was detected we tested the controversial hypothesis regarding ... | 2011 | 22186876 |
| An outbreak of Salmonella enterica serotype Choleraesuis in goitered gazelle (Gazella subgutrosa subgutrosa) and a Malayan tapir (Tapirus indicus). | An outbreak of Salmonella enterica serotype Choleraesuis enteritis occurred in two juvenile goitered gazelles and an adult Malayan tapir over a period of 5 wk at the Minnesota Zoo. Diagnosis was made postmortem on one gazelle and one tapir, and a second gazelle was diagnosed via fecal culture. The death of the tapir was attributed to S. enterica serovar Choleraesuis septicemia, while salmonellosis was considered to be a contributing factor besides ostertagiasis for the death of one goitered gaze ... | 2011 | 22204065 |
| Deletion of glucose-inhibited division (gidA) gene alters the morphological and replication characteristics of Salmonella enterica Serovar typhimurium. | Salmonella is an important food-borne pathogen that continues to plague the United States food industry. Characterization of bacterial factors involved in food-borne illnesses could help develop new ways to control salmonellosis. We have previously shown that deletion of glucose-inhibited division gene (gidA) significantly altered the virulence potential of Salmonella in both in vitro and in vivo models of infection. Most importantly, the gidA mutant cells displayed a filamentous morphology comp ... | 2011 | 22109813 |
| Salmonella bongori provides insights into the evolution of the Salmonellae. | The genus Salmonella contains two species, S. bongori and S. enterica. Compared to the well-studied S. enterica there is a marked lack of information regarding the genetic makeup and diversity of S. bongori. S. bongori has been found predominantly associated with cold-blooded animals, but it can infect humans. To define the phylogeny of this species, and compare it to S. enterica, we have sequenced 28 isolates representing most of the known diversity of S. bongori. This cross-species analysis al ... | 2011 | 21876672 |
| temperature-sensitive mutants of rnase e in salmonella enterica. | rnase e has an important role in mrna turnover and stable rna processing, although the reason for its essentiality is unknown. we isolated conditional mutants of rnase e to provide genetic tools to probe its essential function. in salmonella enterica serovar typhimurium, an extreme slow-growth phenotype caused by mutant ef-tu (gln125arg, tufa499) can be rescued by mutants of rnase e that have reduced activity. we exploited this phenotype to select mutations in rnase e and screened these for temp ... | 2011 | 21949072 |
| Handheld device for real-time, quantitative, LAMP-based detection of Salmonella enterica using assimilating probes. | A simple handheld instrument was designed to enable real-time detection of the LAMP reaction in a standard PCR tube using newly described assimilating probes as sequence-specific reporter molecules. The system was validated using DNA isolated from Salmonella enterica, demonstrating accurate temperature control with little power and little overshoot of setpoint temperatures, with rapid and accurate detection often in less than 30 min and within 20 min for reactions with high (>10(5)) genome copy ... | 2011 | 21982643 |
| binding of the ramr repressor to wild-type and mutated promoters of the rama gene involved in efflux-mediated multidrug resistance in salmonella enterica serovar typhimurium. | the transcriptional activator rama is involved in multidrug resistance (mdr) by increasing expression of the acrab-tolc rnd-type efflux system in several pathogenic enterobacteriaceae. in salmonella enterica serovar typhimurium (s. typhimurium), rama expression is negatively regulated at the local level by ramr, a transcriptional repressor of the tetr family. we here studied the dna-binding activity of the ramr repressor with the rama promoter (p(rama)). as determined by high-resolution footprin ... | 2011 | 22123696 |
| decreased transport restores growth of a salmonella enterica apbc mutant on tricarballylate. | mutants of salmonella enterica lacking apbc have nutritional and biochemical properties indicative of defects in iron-sulfur ([fe-s]) cluster metabolism. an apbc mutant is unable to grow on tricarballylate as a carbon source. based on the ability of apbc to transfer an [fe-s] cluster to an apoprotein, this defect was attributed to poor loading of the [fe-s] cluster-containing tcub enzyme. consistent with these observations, a previous study showed that overexpression of iscu, which encodes an [f ... | 2011 | 22101844 |
| Influence of prior growth conditions, pressure treatment parameters, and recovery conditions on the inactivation and recovery of Listeria monocytogenes, Escherichia coli, and Salmonella Typhimurium in turkey meat. | The relatively high prevalence of Listeria monocytogenes, Escherichia coli O157:H7, and Salmonella enterica serovar Typhimurium in various food products is of great concern to the food industry. The objective of this study was to determine the pressure-inactivation of the pathogens in a representative food model as affected by prior growth temperature, physiological age of the culture, pressure level and treatment temperature. The effect of post-treatment conditions (incubation temperature and g ... | 2011 | 22169000 |
| Salmonella enterica serovar Typhimurium and Enteritidis infection of pigs and cytokine signalling in palatine tonsils. | Pigs are considered as one of the major sources of zoonotic strains of Salmonella enterica for humans. Out of many S. enterica serovars, S. Typhimurium dominates in pigs, however, in several countries in Central Europe, S. Enteritidis is also quite frequent in pig herds. In this study we therefore compared the colonisation of pigs with S. Typhimurium and S. Enteritidis. We found that 3 weeks after infection S. Enteritidis 147 colonised the intestinal tract in higher quantities but was shed in fa ... | 2011 | 22019291 |
| distinct peripheral blood rna responses to salmonella in pigs differing in salmonella shedding levels: intersection of ifng, tlr and mirna pathways. | transcriptomic analysis of the response to bacterial pathogens has been reported for several species, yet few studies have investigated the transcriptional differences in whole blood in subjects that differ in their disease response phenotypes. salmonella species infect many vertebrate species, and pigs colonized with salmonella enterica serovar typhimurium (st) are usually asymptomatic, making detection of these salmonella-carrier pigs difficult. the variable fecal shedding of salmonella is an ... | 2011 | 22174891 |
| nanostructured silver vanadate as a promising antibacterial additive to water-based paints. | in this article, we report the use of nanostructured silver vanadate as a promising antibacterial additive to water-based paints that has potential for applications in bathrooms, kitchens, and hospital environments. this hybrid nanomaterial was prepared by a simple and fast precipitation reaction involving silver nitrate and ammonium vanadate, dismissing the hydrothermal treatment. the preparation involved using ag vanadate nanowires (β-agvo(3)) with diameters ranging from 20 to 60 nm and decora ... | 2011 | 22197722 |
| Genome sequencing reveals diversification of virulence factor content and possible host adaptation in distinct subpopulations of Salmonella enterica. | Divergence of bacterial populations into distinct subpopulations is often the result of ecological isolation. While some studies have suggested the existence of Salmonella enterica subsp. enterica subclades, evidence for these subdivisions has been ambiguous. Here we used a comparative genomics approach to define the population structure of Salmonella enterica subsp. enterica, and identify clade-specific genes that may be the result of ecological specialization. | 2011 | 21859443 |
| Empiric antimicrobial therapy and infectious diarrhea. Do we need local guidelines? | In the management of acute diarrhea, administration of antibiotics may be indicated. Appropriate antimicrobial therapy can shorten illness, reduce morbidity and can be life-saving in invasive infections. Emergence of microbial strains resistant to commonly used antibiotics means that treatment failures may become common. Because of changing patterns of resistance, knowledge of recent local patterns of susceptibility can guide the initial choice of antibiotics. | 2011 | 21925045 |
| Genetic analysis of the pnp-deaD genetic region reveals membrane lipoprotein NlpI as an independent participant in cold acclimatization of Salmonella enterica serovar Typhimurium. | The cold acclimatization response in many bacterial species is a tightly regulated process, which ensures the correct folding of macromolecules. In enterobacteria, this response is in part dependent on polynucleotide phosphorylase, which is encoded by the gene pnp. Based on transcriptional analysis of the pnp locus of Salmonella enterica serovar Typhimurium, we show that pnp and the adjacent membrane lipoprotein nlpI gene form an operon with both genes contributing independently to the cold accl ... | 2011 | 22092862 |
| prevalence of salmonella in fecal samples of western grey kangaroos (macropus fuliginosus). | this is the first extensive study of the prevalence of naturally acquired salmonella infection in wild-caught kangaroos in australia. given the close association between kangaroos, livestock, and humans and the growing popularity of kangaroo meat, it is important to identify epidemiologic factors associated with infection in these marsupials in order to minimize the risk of salmonella transmission. the overall prevalence of fecal salmonella in 645 western grey kangaroos (macropus fuliginosus) sa ... | 2011 | 22102658 |
| Phenotypic and Genotypic Characterization of Salmonella enterica Recovered from Poultry Meat in Tunisia and Identification of New Genetic Traits. | Abstract Thirty-seven Salmonella enterica isolates obtained from poultry meat in Tunisia were included in this study for characterization of antibiotic resistance mechanisms. High percentages of resistance were detected to ampicillin, sulfonamides, tetracycline, nalidixic acid, and streptomycin (32.4%-89.2%), and lower percentages to amoxicillin-clavulanic acid, kanamycin, amikacin, trimethoprim-sulfamethoxazol, and chloramphenicol (2.7%-18.9%). All strains showed susceptibility to ceftazidime ... | 2011 | 21919733 |
| antibiotic control of tumor-colonizing salmonella enterica serovar typhimurium. | systemic administration of salmonella enterica serovar typhimurium (s. typhimurium) into tumor-bearing mice results in preferential colonization of tumors and causes shrinkage and sometimes complete tumor clearance. however, in spite of these beneficial antitumor effects, the systemic administration of a bacterial pathogen raises serious safety concerns as well. addressing those concerns, here, we demonstrate that tumor-colonizing salmonella can be readily controlled by systemic administration o ... | 2011 | 21987828 |
| Complete sequencing of the bla(NDM-1)-positive IncA/C plasmid from Escherichia coli ST38 isolate suggests a possible origin from plant pathogens. | The complete sequence of the plasmid pNDM-1_Dok01 carrying New Delhi metallo-ß-lactamase (NDM-1) was determined by whole genome shotgun sequencing using Escherichia coli strain NDM-1_Dok01 (multilocus sequence typing type: ST38) and the transconjugant E. coli DH10B. The plasmid is an IncA/C incompatibility type composed of 225 predicted coding sequences in 195.5 kb and partially shares a sequence with bla(CMY-2)-positive IncA/C plasmids such as E. coli AR060302 pAR060302 (166.5 kb) and Salmonell ... | 2011 | 21966500 |
| bacteremia and antimicrobial drug resistance over time, ghana. | bacterial distribution and antimicrobial drug resistance were monitored in patients with bacterial bloodstream infections in rural hospitals in ghana. in 2001-2002 and in 2009, salmonella enterica serovar typhi was the most prevalent pathogen. although most s. enterica serovar typhi isolates were chloramphenicol resistant, all isolates tested were susceptible to ciprofloxacin. | 2011 | 22000360 |
| The ERM protein, ezrin, regulates neutrophil transmigration by modulating the apical localization of MRP2 in response to the SipA effector protein during Salmonella Typhimurium infection. | In human disease induced by Salmonella enterica serovar Typhimurium (S. Typhimurium), transepithelial migration of neutrophils rapidly follows attachment of the bacteria to the epithelial apical membrane. We have previously shown that during S. Typhimurium infection the multidrug resistance-associated protein 2 (MRP2) is highly expressed at the apical surface of the intestinal epithelia, and that it functions as an efflux pump for the potent neutrophil chemoattractant hepoxilin A(3) . However, t ... | 2011 | 21899702 |
| reveal salmonella enteritidis test for detection of salmonella enteritidis in shell eggs and environmental samples. | reveal salmonella enteritidis (se) is a lateral flow-based immunodiagnostic assay used for rapid detection of salmonella enterica serovar enteritidis from pooled shell eggs and environmental samples. this assay uses highly specific antibodies to accurately detect s. enteritidis. studies were conducted to compare the performance of this test against reference procedures for detection of s. enteritidis from both pooled shell eggs and environmental samples. pooled shell eggs were inoculated with lo ... | 2011 | 21919347 |
| both the unique and repeat regions of the porphyromonas gingivalis hemagglutin a are involved in adhesion and invasion of host cells. | porphyromonas gingivalis is one of the major etiologic agents of adult periodontitis and has been associated with cardiovascular diseases. it expresses multiple hemagglutinins that are significant virulence factors and play an important role in bacterial attachment and invasion of host cells. the objective of this study was to determine the impact of p. gingivalis hemagglutinin a (haga) on the attachment to and invasion of human coronary artery endothelial cells (hcaec) and gingival epithelial c ... | 2011 | 22100486 |
| Host response transcriptional profiling reveals extracellular components and ABC (ATP-binding cassette) transporters gene enrichment in typhoid fever-infected Nigerian children. | Salmonella enterica serovar Typhi (S. Typhi) is a human-specific pathogen that causes typhoid fever, and remains a global health problem especially in developing countries. Its pathogenesis is complex and host response is poorly understood. In Africa, typhoid fever can be a major cause of morbidity in young infected children. The onset of the illness is insidious and clinical diagnosis is often unreliable. Gold standard blood culture diagnostic services are limited, thus rapid, sensitive, and af ... | 2011 | 21914192 |
| biophysical investigations into the interactions of endotoxins with bile acids. | the interaction of selected endotoxin preparations (lipid a from erwinia carotovora and lps re and ra from salmonella enterica sv. minnesota strains r595 and r60, respectively) with selected bile acids was investigated biophysically. endotoxin aggregates were analyzed for their gel-to-liquid crystalline phase behavior, the type of their aggregates, the conformation of particular functional groups, and their zeta potential in the absence and presence of the bile acids by applying fourier-transfor ... | 2011 | 21954318 |
| complex c-di-gmp signaling networks mediate transition between virulence properties and biofilm formation in salmonella enterica serovar typhimurium. | upon salmonella enterica serovar typhimurium infection of the gut, an early line of defense is the gastrointestinal epithelium which senses the pathogen and intrusion along the epithelial barrier is one of the first events towards disease. recently, we showed that high intracellular amounts of the secondary messenger c-di-gmp in s. typhimurium inhibited invasion and abolished induction of a pro-inflammatory immune response in the colonic epithelial cell line ht-29 suggesting regulation of transi ... | 2011 | 22164276 |
| genetic relationships of phage types and single nucleotide polymorphism typing of salmonella enterica serovar typhimurium. | salmonella enterica serovar typhimurium is one of the leading causes of gastroenteritis in humans. phage typing has been used for epidemiological surveillance of typhimurium for over four decades. however, knowledge of the evolutionary relationships between phage types is very limited. in this study, we used single nucleotide polymorphisms (snps) as molecular markers to determine the relationships between common typhimurium phage types. forty-four snps including 24 identified in a previous study ... | 2011 | 22205813 |
| investigation of salmonella enterica in sardinian slaughter pigs: prevalence, serotype and genotype characterization. | in order to improve the knowledge about the presence of salmonella in pork meat in sardinia (italy), the prevalence and the sources of salmonella at 5 pig slaughterhouses (slaughtered pigs and environment) were investigated and the isolates were characterised. a total of 462 samples were collected, 425 from pigs at slaughter and 41 from the slaughterhouse environment. salmonella was isolated from 26/85 (30.5%) mesenteric lymph nodes, 14/85 (16.4%) colon contents, and from 12/85 (14.1%) carcasses ... | 2011 | 21940060 |
| Role of antigens and virulence factors of Salmonella enterica serovar Typhi in its pathogenesis. | Salmonella enterica serovar Typhi (S. Typhi), the aetiologic agent of typhoid fever, is a human restricted pathogen. The molecular mechanism of Salmonella pathogenicity is complex. The investigations of the molecular mechanisms of Salmonella virulence factors have shown that pathogenic Salmonella spp. are distinguished from their non-pathogenic relatives by the presence of specific pathogenicity genes, often organized in so-called pathogenicity islands (PIs). The type III secretion system (T3SS) ... | 2011 | 21945101 |
| Thiosulfate Reduction in Salmonella enterica Is Driven by the Proton Motive Force. | Thiosulfate respiration in Salmonella enterica serovar Typhimurium is catalyzed by the membrane-bound enzyme thiosulfate reductase. Experiments with quinone biosynthesis mutants show that menaquinol is the sole electron donor to thiosulfate reductase. However, the reduction of thiosulfate by menaquinol is highly endergonic under standard conditions (?E°' = -328 mV). Thiosulfate reductase activity was found to depend on the proton motive force (PMF) across the cytoplasmic membrane. A structural m ... | 2012 | 22081391 |
| Isolation and Characterization of small qnrS1-carrying plasmids from imported seafood isolates of Salmonella enterica that are highly similar to plasmids of clinical isolates. | Dissemination of plasmid-mediated quinolone resistance among pathogenic bacteria is a concern for public health due to decreased sensitivity to fluoroquinolones and increased potentials to develop high fluoroquinolone resistance. Two qnrS1-positive isolates of Salmonella enterica, Corvallis (468) and Typhimurium (484) from imported seafood (Thailand and Vietnam) were tested for quinolone sensitivity using disk agar diffusion and the Sensititre(®) system. The presence of qnr genes, qnr-carrying ... | 2011 | 22151215 |
| evasion of host immunity by virulent salmonella: implications for vaccine design. | dendritic cells (dcs) are professional antigen presenting cells (apcs) capable of linking innate and adaptive immunity during infection. after recognition of pathogen-associated molecular patterns (pamps), dcs can engulf, process and present bacteria-derived antigens on mhc molecules to t cells. because of the key role that dcs play on the initiation of innate and adaptive immunity, alterations in their function could render the host susceptible to bacterial dissemination. consistent with this n ... | 2011 | 22172071 |
| antimicrobial activity of apple, hibiscus, olive, and hydrogen peroxide formulations against salmonella enterica on organic leafy greens. | salmonella enterica is one of the most common bacterial pathogens implicated in foodborne outbreaks involving fresh produce in the last decade. in an effort to discover natural antimicrobials for use on fresh produce, the objective of the present study was to evaluate the effectiveness of different antimicrobial plant extract-concentrate formulations on four types of organic leafy greens inoculated with s. enterica serovar newport. the leafy greens tested included organic romaine and iceberg le ... | 2011 | 22004815 |
| characterization and comparative genomic analysis of a novel bacteriophage, sfp10, simultaneously inhibiting both salmonella enterica and escherichia coli o157:h7. | salmonella enterica and escherichia coli o157:h7 are major food-borne pathogens causing serious illness. phage sfp10, which revealed effective infection of both s. enterica and e. coli o157:h7, was isolated and characterized. sfp10 contains a 158-kb double-stranded dna genome belonging to the vi01 phage-like family myoviridae. in vitro adsorption assays showed that the adsorption constant rates to both salmonella enterica serovar typhimurium and e. coli o157:h7 were 2.50 × 10(-8) ml/min and 1.91 ... | 2012 | 22020516 |