| salmonella in healthy pigs: prevalence, serotype diversity and antimicrobial resistance observed during 1998-1999 and 2004-2005 in japan. | to determine prevalence, serotype diversity and antimicrobial resistance of salmonella in healthy pigs, faecal samples from 6771 pigs on 73 farms collected during 1998-1999 and 2004-2005 were examined. salmonella isolates were serotyped and tested for susceptibility to 22 antimicrobials: benzylpenicillin, ampicillin, amoxicillin, cefazolin, cephaloridine, gentamicin, kanamycin, streptomycin, fradiomycin, colistin, tetracycline, chlortetracycline, oxytetracycline, chloramphenicol, thiamphenicol, ... | 2008 | 17961277 |
| comparison of salmonella enterica subspecies enterica serovar typhimurium isolates from dairy cattle and humans using in vitro assays of virulence. | salmonella enterica subspecies enterica serovar typhimurium (salmonella typhimurium) can infect and cause disease in a wide range of host species however there have been suggestions that this serovar may have genes involved with host range or specificity [tsolis, r.m., townsend, s.m., miao, e.a., miller, s.i., ficht, t.a., adams, l.g., baumler, a.j., 1999. identification of a putative s. enterica serotype typhimurium host range factor with homology to ipah and yopm by signature-tagged mutagenesi ... | 2008 | 17964087 |
| functional characterization of chicken tlr5 reveals species-specific recognition of flagellin. | mammalian toll-like receptor 5 (tlr5) senses flagellin of several bacterial species and activates the innate immune system. the avian tlr repertoire exhibits considerable functional diversity compared to mammalian tlrs and evidence of a functional tlr5 in the avian species is lacking. in the present study we cloned and successfully expressed chicken tlr5 (chtlr5) in hela cells, as indicated by laser confocal microscopy. infection of chtlr5 transfected cells with salmonella enterica serovar enter ... | 2008 | 17964652 |
| detection of salmonella enterica subpopulations by phenotype microarray antibiotic resistance patterns. | three strains of salmonella enterica serotype enteritidis were compared to salmonella enterica serotype heidelberg, salmonella enterica serotype newport, and salmonella enterica serovar typhimurium for growth in the presence of 240 antibiotics arranged within a commercial high-throughput phenotype microarray. the results show that antibiotic resistances were different for subpopulations of serotype enteritidis separated only by genetic drift. | 2007 | 17965201 |
| common epitopes in lps of different enterobacteriaceae are associated with an immune response against escherichia coli o157 in bovine serum samples. | epidemiological studies in both humans and animals conducted in mexico have shown that the isolation frequency of escherichia coli o157 : h7 is low. in a previous study, igg antibodies against e. coli o157, o7 and o116 lps were found in serum samples from children and adults with no previous history of e. coli o157 : h7 infection. the present study was designed to determine whether a similar immune response against e. coli o157 : h7 and other antigenically related bacteria was present in bovine ... | 2007 | 17965343 |
| molecular epidemiology of community-acquired invasive non-typhoidal salmonella among children aged 2 29 months in rural gambia and discovery of a new serovar, salmonella enterica dingiri. | sixty-two invasive non-typhoidal salmonella (nts) isolates from children aged 2-29 months in rural gambia were examined for serovar prevalence and antimicrobial susceptibility, and characterized using multilocus sequence typing (mlst) of seven genes, aroc, dnan, hemd, hisd, pure, suca and thra. salmonella enterica serovar enteritidis was the most common serovar (80.6 %), followed by s. enterica serovar typhimurium (8.0 %). thirty-three per cent of the isolates were resistant to all eight antimic ... | 2007 | 17965348 |
| in vitro activity of azithromycin, newer quinolones and cephalosporins in ciprofloxacin-resistant salmonella causing enteric fever. | the therapeutic alternatives available for use against ciprofloxacin-resistant enteric fever isolates in an endemic area are limited. the antibiotics currently available are the quinolones, third-generation cephalosporins and conventional first-line drugs. in this study, the mics of various newer drugs were determined for 31 ciprofloxacin-resistant enteric fever isolates (26 salmonella enterica serovar typhi and 5 s. enterica serovar paratyphi a). mics for ciprofloxacin, ofloxacin, gatifloxacin, ... | 2007 | 17965350 |
| oral vaccination with salmonella enterica as a cruzipain-dna delivery system confers protective immunity against trypanosoma cruzi. | to stimulate both local and systemic immune responses against trypanosoma cruzi, salmonella enterica serovar typhimurium aroa was exploited as a dna delivery system for cruzipain (scz). in a murine model we compared scz alone (gi) or coadministered with salmonella carrying a plasmid encoding granulocyte-macrophage colony-stimulating factor (gii), as well as protocols in which scz priming was followed by boosting with recombinant cruzipain (rcz) admixed with either cpg-odn (giii) or malp-2, a syn ... | 2008 | 17967857 |
| host transmission of salmonella enterica serovar typhimurium is controlled by virulence factors and indigenous intestinal microbiota. | transmission is an essential stage of a pathogen's life cycle and remains poorly understood. we describe here a model in which persistently infected 129x1/svj mice provide a natural model of salmonella enterica serovar typhimurium transmission. in this model only a subset of the infected mice, termed supershedders, shed high levels (>10(8) cfu/g) of salmonella serovar typhimurium in their feces and, as a result, rapidly transmit infection. while most salmonella serovar typhimurium-infected mice ... | 2008 | 17967858 |
| antimicrobial resistance genes associated with salmonella enterica serovar newport isolates from food animals. | salmonella enterica serotype newport is an important cause of salmonellosis, with strains increasingly being resistant to multiple antimicrobial agents. the increase is associated with the acquisition of multiple resistance genes. this study characterizes the genetic basis of resistance of serotype newport isolates collected from veterinary sources by pcr and dna sequencing analysis. | 2008 | 17967918 |
| pathogens on aspirin: promising research and therapeutic applications. | | 2007 | 17971779 |
| translational genomics to develop a salmonella enterica serovar paratyphi a multiplex polymerase chain reaction assay. | the use of pathogen genome sequence data for the control and management of infections remains an ongoing challenge. we describe a broadly applicable, web-enabled approach that can be used to develop bacteria-specific polymerase chain reaction (pcr) assays. salmonella enterica paratyphi a has emerged as a major cause of enteric fever in asia. culture-based diagnosis is slow and frequently negative in patients with suspected typhoid and paratyphoid fever, potentially compromising patient managemen ... | 2007 | 17975028 |
| a conserved toll-like receptor is required for caenorhabditis elegans innate immunity. | pathogen recognition through toll-like receptors (tlrs) is crucial in order to mount an appropriate immune response against microorganisms. on the basis of a lack of evidence indicating that caenorhabditis elegans uses tlrs to elicit an immune response and on the absence of genes encoding rel-like transcription factors in its genome, it is believed that tlr-mediated immunity arose after coelomates split from pseudocoelomates and acoelomates. here, we show that c. elegans tol-1(nr2033) mutants ar ... | 2008 | 17975555 |
| a linear plasmid truncation induces unidirectional flagellar phase change in h:z66 positive salmonella typhi. | the process by which bacteria regulate flagellar expression is known as phase variation and in salmonella enterica this process permits the expression of one of two flagellin genes, flic or fljb, at any one time. salmonella typhi (s. typhi) is normally not capable of phase variation of flagellar antigen expression as isolates only harbour the flic gene (h:d) and lacks an equivalent fljb locus. however, some s. typhi isolates, exclusively from indonesia, harbour an fljb equivalent encoded on line ... | 2007 | 17976161 |
| development of a new water sterilization device with a 365 nm uv-led. | ultraviolet (uv) irradiation is an effective disinfection method. in sterilization equipment, a low-pressure mercury lamp emitting an effective germicidal uvc (254 nm) is used as the light source. however, the lamp, which contains mercury, must be disposed of at the end of its lifetime or following damage due to physical shock or vibration. we investigated the suitability of an ultraviolet light-emitting diode at an output wavelength of 365 nm (uva-led) as a sterilization device, comparing with ... | 2007 | 17978842 |
| a female-specific pentraxin, croctin, bridges pattern recognition receptors to bacterial phosphoethanolamine. | pathogen recognition and binding are crucial functions of innate immunity. it has been observed that the short pentraxin superfamily including c-reactive protein (crp) and serum amyloid p component are pathogen pattern recognition receptors (prr) in the plasma. we isolated and characterized a novel and distinctive pentraxin from the plasma of horseshoe crab, carcinoscorpius rotundicauda, henceforth named croctin, which binds to bacteria via phosphoethanolamine (pe), a chemical component present ... | 2007 | 17979155 |
| the leucine-responsive regulatory protein, lrp, activates transcription of the fim operon in salmonella enterica serovar typhimurium via the fimz regulatory gene. | the fim operon of salmonella enterica serovar typhimurium encodes type 1 fimbriae. the expression of fim is controlled in response to environmental signals through a complex regulatory cascade involving the proteins fimw, fimy, and fimz and a genetic locus, fimu, that encodes a rare arginine trna. we discovered that a knockout mutation in lrp, the gene that codes for the leucine-responsive regulatory protein (lrp), inhibited fim transcription. the loss of fim gene expression was accompanied by a ... | 2008 | 17981960 |
| one pathway can incorporate either adenine or dimethylbenzimidazole as an alpha-axial ligand of b12 cofactors in salmonella enterica. | corrinoid (vitamin b12-like) cofactors contain various alpha-axial ligands, including 5,6-dimethylbenzimidazole (dmb) or adenine. the bacterium salmonella enterica produces the corrin ring only under anaerobic conditions, but it can form "complete" corrinoids aerobically by importing an "incomplete" corrinoid, such as cobinamide (cbi), and adding appropriate alpha- and beta-axial ligands. under aerobic conditions, s. enterica performs the corrinoid-dependent degradation of ethanolamine if given ... | 2008 | 17981976 |
| evidence of lethal and sublethal injury in food-borne bacterial pathogens exposed to high-intensity pulsed-plasma gas discharges. | to apply scanning electron microscopy, image analysis and a fluorescent viability stain to assess lethal and sublethal injury in food-borne bacteria exposed to pulsed-plasma gas discharges (ppgd). | 2008 | 17983430 |
| membrane dynamics and spatial distribution of salmonella-containing vacuoles. | salmonella enterica are facultative intracellular bacteria that cause intestinal and systemic diseases, and replicate within host cells in a membrane-bound compartment, the salmonella-containing vacuole. intravacuolar bacterial replication depends on spatiotemporal regulated interactions with host cell vesicular compartments. recent studies have shown that type iii secretion effector proteins control both the vacuolar membrane dynamics and intracellular positioning of bacterial vacuoles. the fun ... | 2007 | 17983751 |
| salmonella infection of afferent lymph dendritic cells. | the interactions of salmonella enterica subspecies i serotype abortusovis (s. abortusovis) with ovine afferent lymph dendritic cells (aldcs) were investigated for their ability to deliver maedi visna virus (mvv) gag p25 antigens to aldcs purified from afferent lymph. salmonellae were found to enter aldc populations by a process of cell invasion, as confirmed by electron and confocal microscopy. this led to phenotypical changes in aldc populations, as defined by cd1b and cd14 expression. no diffe ... | 2008 | 17986631 |
| the role of roof rats ( rattus rattus) in the spread of salmonella enteritidis and s. infantis contamination in layer farms in eastern japan. | the prevalence of salmonella in four layer farms in eastern japan was investigated between 2004 and 2006 to determine the role of roof rats (rattus rattus) in the epizootology of salmonella enterica subsp. enterica serovar enteritidis (s. enteritidis). persistent s. enteritidis and s. infantis contamination of the environment and pooled egg samples were detected in three out of four layer farms. a total of 113 (13.3%) and 158 (18.6%) out of 851 rats examined were positive for s. enteritidis and ... | 2008 | 17988423 |
| effect of fixed or changing temperatures during prolonged storage on the growth of salmonella enterica serovar enteritidis inoculated artificially into shell eggs. | the fate of salmonella enterica serovar enteritidis (se) in whole, unbroken eggs was monitored during storage at fixed or changing temperatures after inoculation with 20-47 c.f.u. of se. eggs stored at 10 degrees c and 20 degrees c showed little or no bacterial growth over 6 weeks, while egg storage at 30 degrees c increased the percentage of the eggs that contained >10(6) c.f.u. after 3 weeks. egg storage at 20 degrees c for 5 days followed by 10 degrees c caused only a few eggs with >10(6) c.f ... | 2008 | 17988424 |
| salmonella typhimurium infection associated with raw milk and cheese consumption--pennsylvania, 2007. | in february 2007, the pennsylvania department of health received reports, through routine electronic laboratory disease reporting, of two persons with recent laboratory-confirmed infections with salmonella enterica serotype typhimurium. both persons had reported drinking raw (unpasteurized) milk from the same york county, pennsylvania, dairy (dairy a). s. typhimurium isolates from these persons had pulsed-field gel electrophoresis (pfge) patterns that were indistinguishable by use of the xbai re ... | 2007 | 17989645 |
| an easter outbreak of salmonella typhimurium dt 104a associated with traditional pork salami in italy. | salmonella enterica is a common cause of gastrointestinal illness in italy. s. typhimurium accounts for approximately 40% of isolates, and most of these strains belong to the phage type dt104. we describe the investigation of an outbreak of s. typhimurium dt104a, a subtype never observed before in italy, which occurred in rome during spring 2004.we conducted a matched case control study between 24 july and 9 september 2004. controls were matched for age and area of residence. each case had betwe ... | 2007 | 17991384 |
| outbreaks of monophasic salmonella enterica serovar 4,[5],12:i:- in luxembourg, 2006. | a monophasic salmonella enterica serovar 4,[5],12:i:- phage type dt193 emerged as the dominant serovar in luxembourg in 2006, when it caused two major outbreaks involving 133 laboratory-confirmed human cases, 24 hospitalisations, and one death. the outbreak strain had an uncommon pulsed-field gel electrophoresis pattern stymxb.0031 and antibiotic resistance profile assut. a high proportion of cases were clustered in institutions for the elderly and in day-care centers. strains identical to the o ... | 2007 | 17991400 |
| prevalence and characterization of salmonella enterica serovar weltevreden from imported seafood. | during 2001-2005, 210 salmonella enterica strains were isolated from seafood samples imported into us. strains of s. enterica serovar weltevreden were the most predominantly found among the 64 different serovars isolated. a total of 37 salmonella weltevreden isolates were characterized by pulsed-field gel electrophoresis (pfge), plasmid profiles and antibiotic susceptibility to assess genetic diversity. our results showed a low frequency of antibiotic resistance; 35 of the 37 isolates were sensi ... | 2008 | 17993374 |
| fur regulates expression of the salmonella pathogenicity island 1 type iii secretion system through hild. | the invasion of intestinal epithelial cells by salmonella enterica serovar typhimurium is mediated by a type iii secretion system (t3ss) encoded on salmonella pathogenicity island 1 (spi1). expression of the spi1 t3ss is tightly regulated by the combined action of hilc, hild, and rtsa, three arac family members that can independently activate hila, which encodes the direct regulator of the spi1 structural genes. expression of hilc, hild, and rtsa is controlled by a number of regulators that resp ... | 2008 | 17993530 |
| protective efficacy of live salmonella gallinarum 9r vaccine in commercial layer flocks. | salmonella enterica serovar gallinarum (s. gallinarum) is the causative agent of fowl typhoid, a severe systemic disease of chickens that results in high mortality. in this study we re-evaluated the ability of live s. gallinarum 9r vaccine to protect from wild-type s. gallinarum challenge. in laboratory trials, there was a significant difference between the vaccinated and unvaccinated control groups in mortality and the re-isolation rate of the challenge strain from the tissues (p<0.05). in fiel ... | 2007 | 17994329 |
| phenolic acids from plant foods can increase or decrease the mutation frequency to antibiotic resistance. | phenolic compounds are ubiquitous in plant foods, and they have been reported to have multiple biological effects. this study investigates the ability of derivatives of hydroxybenzoic and hydroxycinnamic acids to influence the development of ciprofloxacin resistance in the antibiotic-sensitive strain salmonella enterica subsp. enterica serovar typhimurium. we have found that cinnamic acid and its hydroxy derivatives increase the frequency of mutations leading to ciprofloxacin resistance in compa ... | 2007 | 17994694 |
| safety of typhim vi vaccine in a postmarketing observational study. | typhoid fever is endemic in many parts of the world. in the united states, nearly three quarters of all cases are contracted by persons who traveled to regions with endemic disease. typhim vi, a vaccine containing the purified cell surface vi polysaccharide of the salmonella enterica serovar typhi, was developed to provide protection against typhoid fever. we present the results of the largest safety study of this vi vaccine to date. | 2007 | 17995534 |
| recipes for antimicrobial wine marinades against bacillus cereus, escherichia coli o157:h7, listeria monocytogenes, and salmonella enterica. | we have evaluated bactericidal activities against bacillus cereus, escherichia coli o157:h7, listeria monocytogenes, and salmonella enterica of several antimicrobial wine recipes, each consisting of red or white wine extracts of oregano leaves with added garlic juice and oregano oil. dose-response plots were used to determine the percentage of the recipes that resulted in a 50% decrease in colony-forming units (cfu) at 60 min (ba(50)). studies designed to optimize antibacterial activities of the ... | 2007 | 17995688 |
| inhibition of foodborne pathogens by native microflora recovered from fresh peeled baby carrot and propagated in cultures. | the inhibitory effect of fresh peeled baby carrot and associated microflora on the viability and growth of listeria monocytogenes, yersinia enterocolitica, salmonella enterica, escherichia coli o157:h7, and pseudomonas marginalis was investigated. the population of viable l. monocytogenes was reduced by more than 2 logs following the dipping of sliced baby carrots in the bacterial suspension for 2 min. however, other pathogens subjected to the same treatment showed no reduction in the population ... | 2007 | 17995781 |
| effect of molecular weight, type of chitosan, and chitosan solution ph on the shelf-life and quality of coated eggs. | effects of the molecular weight and type of chitosans and ph of chitosan solution on antibacterial activity against salmonella enterica enteritidis and on internal quality of chitosan-coated eggs were evaluated during 4 wk of storage at 25 degrees c. two types of chitosans were studied: alpha-chitosans with 4 different molecular weights (mw = 282, 440, 746, and 1110 kda) and beta-chitosan (mw = 577 kda). the alpha-chitosan with 282 kda exhibited stronger bactericidal effects than did other alpha ... | 2007 | 17995896 |
| the role of the qsec quorum-sensing sensor kinase in colonization and norepinephrine-enhanced motility of salmonella enterica serovar typhimurium. | transcriptional analysis of salmonella enterica serovar typhimurium (s. typhimurium) in the presence of the mammalian hormone norepinephrine revealed up-regulation of genes in the flagellar and chemotaxis regulon. motility assays confirmed enhanced motility of wild-type s. typhimurium in the presence of norepinephrine that could be blocked by the alpha-adrenergic antagonist, phentolamine. furthermore, a mutation in the qsec gene, encoding the sensor kinase of the two-component qsebc quorum-sensi ... | 2008 | 17997077 |
| immunological responses against salmonella enterica serovar typhimurium braun lipoprotein and lipid a mutant strains in swiss-webster mice: potential use as live-attenuated vaccines. | we generated and characterized salmonella enterica serovar typhimurium mutants that were deleted for the genes encoding braun lipoprotein (lpp) alone or in conjunction with the msbb gene, which codes for an enzyme required for the acylation of the lipid a moiety of lipopolysaccharide. two copies of the lpp gene, designated as lppa and lppb, exist on the chromosome of s. typhimurium. these mutants were highly attenuated in a mouse infection model and induced minimal histopathological changes in m ... | 2008 | 17997275 |
| a structural study of gdp-4-keto-6-deoxy-d-mannose-3-dehydratase: caught in the act of geminal diamine formation. | di- and trideoxysugars are an important class of carbohydrates synthesized by certain plants, fungi, and bacteria. colitose, for example, is a 3,6-dideoxysugar found in the o-antigens of gram-negative bacteria such as escherichia coli, salmonella enterica, yersinia pseudotuberculosis, and vibrio cholerae, among others. these types of dideoxysugars are thought to serve as antigenic determinants and to play key roles in bacterial defense and survival. four enzymes are required for the biochemical ... | 2007 | 17997582 |
| fitness and dissemination of disinfectant-selected multiple-antibiotic-resistant (mar) strains of salmonella enterica serovar typhimurium in chickens. | the aims of this study were to determine whether strains of salmonella enterica serovar typhimurium which had acquired low-level multiple antibiotic resistance (mar) through repeated exposure to farm disinfectants were able to colonize and transmit between chicks as easily as the parent strain and, if such strains were less susceptible to fluoroquinolones, would high-level resistance be selected after fluoroquinolone treatment. | 2008 | 17999979 |
| sipc multimerization promotes actin nucleation and contributes to salmonella-induced inflammation. | actin nucleation is the rate-limiting step in actin assembly and is regulated by actin-binding proteins and signal transduction molecules. salmonella enterica serovar typhimurium exploits actin dynamics by reorganizing the host actin cytoskeleton to facilitate its own uptake. sipc is a salmonella actin-binding protein that nucleates actin filament formation in vitro. the molecular mechanism by which sipc nucleates actin is not known. we show here that sipc(199-409) forms multimers to promote act ... | 2007 | 18005098 |
| salmonella spi1 effector sipa persists after entry and cooperates with a spi2 effector to regulate phagosome maturation and intracellular replication. | salmonellae employ two type iii secretion systems (t3sss), spi1 and spi2, to deliver virulence effectors into mammalian cells. spi1 effectors, including actin-binding sipa, trigger initial bacterial uptake, whereas spi2 effectors promote subsequent replication within customized salmonella-containing vacuoles (scvs). scvs sequester actin filaments and subvert microtubule-dependent motors to migrate to the perinuclear region. we demonstrate that sipa delivery continues after salmonella internaliza ... | 2007 | 18005682 |
| type iii secretion effectors of the ipah family are e3 ubiquitin ligases. | many bacteria pathogenic for plants or animals, including shigella spp., which is responsible for shigellosis in humans, use a type iii secretion apparatus to inject effector proteins into host cells. effectors alter cell signaling and host responses induced upon infection; however, their precise biochemical activities have been elucidated in very few cases. utilizing saccharomyces cerevisiae as a surrogate host, we show that the shigella effector ipah9.8 interrupts pheromone response signaling ... | 2007 | 18005683 |
| interference with the quorum sensing systems of salmonella enterica serovar typhimurium: possibilities and implications. | | 2007 | 18018856 |
| emerging trends in enteric fever in nepal: 9124 cases confirmed by blood culture 1993-2003. | this was a retrospective study in an urban hospital in kathmandu, nepal to determine the changing burden of salmonella septicaemia, the proportion of salmonella paratyphi a, and the emergence of drug-resistant organisms. the participants were outpatients and inpatients over the period 1993-2003, and the main outcome measures were blood culture isolates and antibiotic sensitivity testing. the results showed that of 82467 blood cultures performed, a bacterium was isolated from 12252. salmonella ac ... | 2008 | 18023462 |
| cloning, expression and characterization of heat shock protein 60 (groel) of salmonella enterica serovar typhi and its role in protective immunity against lethal salmonella infection in mice. | heat shock proteins (hsps) represent dominant antigens in numerous microbial infections, suggesting a potential use of pathogen-derived hsps for vaccination. the present study evaluates the immunogenicity and protective efficacy of groel (hsp60) of salmonella enterica serovar typhi against lethal challenge by s. typhi ty2 and salmonella enterica serovar typhimurium in mice. the groel gene was cloned and expressed in escherichia coli bl21 and purified by affinity chromatography. immunization of m ... | 2008 | 18024219 |
| luxs affects flagellar phase variation independently of quorum sensing in salmonella enterica serovar typhimurium. | luxs catalyzes the synthesis of the quorum-sensing signaling molecule autoinducer 2. we show that in salmonella enterica serovar typhimurium, deletion of the luxs gene polarizes flagellar phase variation toward the more immunogenic phase 1 flagellin. this phenotype is complementable by luxs in trans but is independent of quorum-sensing signals. | 2008 | 18024511 |
| salmonella enterica burden in harvest-ready cattle populations from the southern high plains of the united states. | our objectives were to quantify the salmonella enterica burdens in harvest-ready cattle and to identify specific at-risk populations of cattle most likely to harbor multiply resistant s. enterica. hide swabs were collected in abattoirs from three cohorts of cattle (feedlot origin cattle that had achieved desirable harvest characteristics and dairy- and beef-type cows harvested because of poor productivity). feces were collected from two cohorts housed in feedlots (cattle that had achieved desira ... | 2008 | 18024678 |
| influence of gastric acid on susceptibility to infection with ingested bacterial pathogens. | despite the widely held belief that gastric acid serves as a barrier to bacterial pathogens, there are almost no experimental data to support this hypothesis. we have developed a mouse model to quantify the effectiveness of gastric acid in mediating resistance to infection with ingested bacteria. mice that were constitutively hypochlorhydric due to a mutation in a gastric h(+)/k(+)-atpase (proton pump) gene were infected with yersinia enterocolitica, salmonella enterica serovar typhimurium, citr ... | 2008 | 18025100 |
| variable number tandem repeat typing of bacteria. | analysis of bacterial genomes revealed a high percentage of dna consisting of repeats, in which dna motifs existed in multiple copies. study of these dna motifs has resulted in the development of variable number tandem repeat (vntr) or multilocus variant-repeat analysis (mlva) assays, which have shown to be valuable bacterial typing methods, especially in relation to disease outbreaks. the vntr-based assay is based on direct pcr amplification of a specific locus, which is well defined. the range ... | 2007 | 18025706 |
| salmonellae interplay with host cells. | salmonellae are important causes of enteric diseases in all vertebrates. characterization of the molecular mechanisms that underpin the interactions of salmonellae with their animal hosts has advanced greatly over the past decade, mainly through the study of salmonella enterica serovar typhimurium in tissue culture and animal models of infection. knowledge of these bacterial processes and host responses has painted a dynamic and complex picture of the interaction between salmonellae and animal c ... | 2008 | 18026123 |
| in vitro effect of subinhibitory concentrations of antibiotics on biofilm formation by clinical strains of salmonella enterica serovar typhimurium isolated in slovakia. | in this study, we examined the biofilm formation of 75 salmonella enterica serovar typhimurium (salm. typhimurium) human clinical isolates and the effect of subinhibitory concentrations (sub-mics) of gentamicin, ciprofloxacin and cefotaxime on biofilm formation and exopolysaccharides (eps) production. | 2008 | 18028358 |
| improved diagnosis specificity in bone and joint infections using molecular techniques. | the microbiological diagnosis of osteoarticular infections currently relies on microbiological cultures, to specifically target treatment. however, these conventional methods sometimes lack of sensitivity and of specificity to establish definitive diagnosis. this study was conducted to determine whether molecular method could improve bacterial bone and joint infection diagnosis. | 2007 | 18029022 |
| molting in salmonella enteritidis-challenged laying hens fed alfalfa crumbles. iii. blood plasma metabolite response. | the objective of this study was to examine an alfalfa crumble diet as an alternative molt diet and compare the physiological response of hens to the responses of feed-deprived molted hens. hens >50 wk old were placed into 6 treatment groups (12 hens per group in trial 1 and 10 hens per group in trial 2): nonmolted salmonella enterica serovar enteritidis positive (ff+), nonmolted salmonella enteritidis negative (ff-), feed withdrawal salmonella enteritidis positive (fw+), fw salmonella enteritidi ... | 2007 | 18029794 |
| molting in salmonella enteritidis-challenged laying hens fed alfalfa crumbles. iv. immune and stress protein response. | immunological responses of molting hens either infected or not infected with salmonella enterica serovar enteritidis were compared in 2 trials with single comb white leghorn hens >50 wk old. the hens were placed into 6 treatment groups with 12 hens per group: nonmolted salmonella enteritidis positive (ff+), non-molted salmonella enteritidis negative (ff-), feed withdrawal salmonella enteritidis positive (fw+), fw salmonella enteritidis negative (fw-), alfalfa salmonella enteritidis positive (alc ... | 2007 | 18029795 |
| identification of prophages in bacterial genomes by dinucleotide relative abundance difference. | prophages are integrated viral forms in bacterial genomes that have been found to contribute to interstrain genetic variability. many virulence-associated genes are reported to be prophage encoded. present computational methods to detect prophages are either by identifying possible essential proteins such as integrases or by an extension of this technique, which involves identifying a region containing proteins similar to those occurring in prophages. these methods suffer due to the problem of l ... | 2007 | 18030328 |
| during infection of epithelial cells salmonella enterica serovar typhimurium undergoes a time-dependent transcriptional adaptation that results in simultaneous expression of three type 3 secretion systems. | the biogenesis of the salmonella-containing vacuole within mammalian cells has been intensively studied over recent years. however, the ability of salmonella to sense and adapt to the intracellular environment of different types of host cells has received much less attention. to address this issue, we report the transcriptome of salmonella enterica serovar typhimurium sl1344 within epithelial cells and show comparisons with salmonella gene expression inside macrophages. we report that s. typhimu ... | 2008 | 18031307 |
| an outbreak of salmonella enterica serovar othmarschen at a funeral service in guri-si, south korea. | | 2007 | 18032851 |
| decontamination of escherichia coli o157:h7 and salmonella enterica on blueberries using ozone and pulsed uv-light. | efficacy of gaseous ozone, aqueous ozone, and pulsed uv-light was evaluated for the purpose of decontaminating blueberries artificially contaminated with either escherichia coli o157:h7 or salmonella. blueberries were exposed to 4 different gaseous ozone treatments: continuous ozone exposure, pressurized ozone exposure, and 2 combined treatments. maximum reductions of salmonella and e. coli o157:h7 after 64-min pressurized or 64-min continuous exposure were 3.0 and 2.2 log(10) cfu/g, respectivel ... | 2007 | 18034733 |
| the vi-capsule prevents toll-like receptor 4 recognition of salmonella. | the viab locus enables salmonella enterica serotype typhi to reduce toll-like receptor (tlr) dependent cytokine production in tissue culture models. this dna region contains genes involved in the regulation (tvia), biosynthesis (tvibcde) and export (vexabcde) of the vi capsule. expression of the vi capsule in s. typhimurium, but not expression of the tvia regulatory protein, reduced tumour necrosis factor-alpha (tnf-alpha) and il-6 production by murine bone-marrow derived macrophages. production ... | 2008 | 18034866 |
| microbiological differences between cull cattle slaughtered at an abattoir and cull cattle slaughtered on farms. | tissue samples from 27 casualty adult dairy cattle slaughtered on farms and 32 'normal' cull dairy cattle were analysed microbiologically for total viable counts (tvc), enterobacteriaceae, escherichia coli o157, salmonella enterica and campylobacter species. overall the counts of enterobacteriaceae and tvc were higher in the animals slaughtered on farms, particularly in the spleen. one 'normal' animal yielded e coli o157, and one yielded campylobacter jejuni, and eight of the cattle slaughtered ... | 2007 | 18037694 |
| peptide mimotopes of complex carbohydrates in salmonella enterica serovar typhi which react with both carbohydrate-specific monoclonal antibody and polyclonal sera from typhoid patients. | polyclonal sera from typhoid patients and a monoclonal antibody, mab atvi, which recognizes the capsular polysaccharide vi antigen (vicps), were used to select for peptides that mimic the vicps by using a phage-displayed random 12-mer peptide library. two major common mimotopes selected from the library carried the amino acid sequences tshhdshglhrv and enhspvniahkl. enzyme-linked immunosorbent assays (elisas) showed that these peptides carry mimotopes to vicps. phage clones that contained the 12 ... | 2007 | 18037781 |
| modulation of horizontally acquired genes by the hha-ydgt proteins in salmonella enterica serovar typhimurium. | we describe a transcriptomic study of the effect of hha and ydgt mutations in salmonella enterica serovar typhimurium. a large number of genes showing altered expression are located in at-rich horizontally acquired dna sequences. many of these genes have also been reported to be targets for h-ns. as hha and ydgt interact with h-ns, our findings strongly suggest that hha and/or ydgt must form complexes with h-ns when they silence these dna regions. | 2008 | 18039769 |
| in vitro activity of cefpodoxime, an expanded-spectrum cephalosporin, against salmonella enterica serotype typhi. | | 2008 | 18039924 |
| evidence for neuromodulation of enteropathogen invasion in the intestinal mucosa. | the extensively innervated intestinal mucosa encompasses a vast surface exposed to an array of potentially infectious microorganisms. we investigated the role of enteric nerves in modulating intracellular internalization of a multidrug-resistant salmonella typhimurium dt104 field isolate in mucosa-submucosa sheets from the porcine ileum, a biomedical model for the human intestine. the effects of transmural electrical stimulation and drugs on intracellular internalization of salmonella over 90 mi ... | 2007 | 18040851 |
| occurrence of qace/qacedelta1 genes and their correlation with class 1 integrons in salmonella enterica isolates from poultry and swine. | in this study, a total of 122 salmonella enterica isolates from poultry and swine were assessed for susceptibility to clinically important antibiotics and to benzalkonium chloride (bkc). all isolates were examined for the presence of the antiseptic resistance genes qace and qacedelta1 and intl1 (class 1 integrase). the intl1-positive strains were further investigated for the presence of the 3' conserved region. the results demonstrated widespread distribution of qacedelta1 (27%) but no isolate w ... | 2007 | 18041302 |
| the use of bulk tank milk samples to monitor trends in antimicrobial resistance on dairy farms. | the routine monitoring of bacteria obtained from bulk tank milk (btm) may be an important tool for detecting farm-level trends in antimicrobial resistance on dairy farms. this study describes and compares antimicrobial susceptibility patterns of salmonella enterica subspecies enterica (salmonella) and escherichia coli recovered from dairy btm. btm from more than 400 dairies in a dairy-intense region of california were sampled eight times at 2- to 3-month intervals over a 29-month period. from sa ... | 2007 | 18041950 |
| longitudinal study of a clonal, subclinical outbreak of salmonella enterica subsp. enterica serovar cerro in a u.s. dairy herd. | salmonellae are a major group of foodborne pathogens known to affect both humans and animals. dairy cattle are a known reservoir of these bacteria and human salmonella infections have been associated with the consumption of improperly processed or contaminated dairy products. many of the over 2500 known serotypes of salmonella are known to infect cattle, resulting in asymptomatic to fatal salmonellosis. this study describes the course of a salmonella outbreak and subsequent endemic infection on ... | 2007 | 18041954 |
| parenteral long-acting amoxicillin reduces intestinal bacterial community diversity in piglets even 5 weeks after the administration. | we investigated the long-term effects of a single intramuscular administration of amoxicillin (15 mg kg(-1)) 1 day after birth, on piglet intestinal microbiota. animals received no creep feed before weaning on day 28 of age. for the next 11 days, the piglets received a wheat-barley-based diet. colon digesta samples were collected on day 39 and subjected to denaturing gradient gel electrophoresis (dgge) of pcr-amplified 16s rrna gene fragments. dgge fingerprint diversity indices differed between ... | 2007 | 18043627 |
| the geomicrobiology of gold. | microorganisms capable of actively solubilizing and precipitating gold appear to play a larger role in the biogeochemical cycling of gold than previously believed. recent research suggests that bacteria and archaea are involved in every step of the biogeochemical cycle of gold, from the formation of primary mineralization in hydrothermal and deep subsurface systems to its solubilization, dispersion and re-concentration as secondary gold under surface conditions. enzymatically catalysed precipita ... | 2007 | 18043665 |
| differential interaction of salmonella enterica serovars with lettuce cultivars and plant-microbe factors influencing the colonization efficiency. | the availability of knowledge of the route of infection and critical plant and microbe factors influencing the colonization efficiency of plants by human pathogenic bacteria is essential for the design of preventive strategies to maintain safe food. this research describes the differential interaction of human pathogenic salmonella enterica with commercially available lettuce cultivars. the prevalence and degree of endophytic colonization of axenically grown lettuce by the s. enterica serovars r ... | 2007 | 18043669 |
| determination of 5-log reduction times for food pathogens in acidified cucumbers during storage at 10 and 25 degrees c. | outbreaks of acid-resistant foodborne pathogens in acid foods with ph values below 4.0, including apple cider and orange juice, have raised concerns about the safety of acidified vegetable products. for acidified vegetable products with ph values between 3.3 and 4.6, previous research has demonstrated that thermal treatments are needed to achieve a 5-log reduction in the numbers of escherichia coli o157:h7, listeria monocytogenes, or salmonella enterica. for some acidified vegetable products wit ... | 2007 | 18044448 |
| antimicrobial activity of flavonoids extracted from bergamot (citrus bergamia risso) peel, a byproduct of the essential oil industry. | to evaluate the antimicrobial properties of flavonoid-rich fractions derived from bergamot peel, a byproduct from the citrus fruit processing industry and the influence of enzymatic deglycosylation on their activity against different bacteria and yeast. | 2007 | 18045389 |
| a rapid monitoring assay for the detection of salmonella spp. and salmonella senftenberg strain w775 in composts. | the composting process needs to be validated for its hygienic status in order to ensure that it is free of pathogens. generally, this is evaluated through temperature monitoring, or additionally through active inoculation and monitoring of indicator organisms. we aimed to develop a monitoring method for the heat-resistant indicator organism salmonella enterica ssp. enterica serovar senftenberg strain w775 for detection in composting biowastes. | 2007 | 18045394 |
| innate immunity to intraphagosomal pathogens is mediated by interferon regulatory factor 8 (irf-8) that stimulates the expression of macrophage-specific nramp1 through antagonizing repression by c-myc. | macrophages are a central arm of innate immune defense against intracellular pathogens. they internalize microbes into phagosomes where the invaders are being killed by oxygen and nitrogen reactive species. despite this battery of antimicrobial molecules, some are able to thrive within the phagosome thus termed intraphagosomal pathogens among which are salmonella, leishmania, and mycobacteria. in mice, a single dominant gene termed nramp1/slc11a1 controls innate resistance to such pathogens. thi ... | 2008 | 18045875 |
| protein expression diversity amongst serovars of salmonella enterica. | salmonella enterica is one of the most extensively studied bacterial species in terms of physiology, genetics, cell culture and development. as a very diverse group, the serovars of s. enterica display a spectrum of host specificities ranging from a broad host range to strictly host-adapted variants. this study utilized a classic proteomic approach combining 2d gel electrophoresis and mass spectrometry for the comparative analysis of the proteomes of serovars typhimurium, enteritidis, choleraesu ... | 2007 | 18048932 |
| a response surface model based on absorbance data for the growth rates of salmonella enterica serovar typhimurium as a function of temperature, nacl, and ph. | response surface model was developed for predicting the growth rates of salmonella enterica sv. typhimurium in tryptic soy broth (tsb) medium as a function of combined effects of temperature, ph, and nacl. the tsb containing six different concentrations of nacl (0, 2, 4, 6, 8, and 10%) was adjusted to an initial of six different ph levels (ph 4, 5, 6, 7, 8, 9, and 10) and incubated at 10 or 20 degrees c. in all experimental variables, the primary growth curves were well (r2 = 0.900 to 0.996) fit ... | 2007 | 18051277 |
| antibacterial activity of thonningia sanguinea against some multi-drug resistant strains of salmonella enterica. | the emergence of strains of s.enterica with multiple drug resistance (mdr) is of great concern worldwide.the extracts of flowers of thonningia sanguinea are used in traditional medicine in ivory coast to treat diarrhoeal diseases including salmonellosis. previous studies had shown inhibition of the mdr strain salmonella enteritidis lysotype 6. | 2007 | 18052869 |
| [about a patient with nalidixic-acid-resistant salmonella enterica serotype typhi infection. therapeutic management]. | | 2007 | 18053478 |
| antimicrobial resistance in salmonella enterica serovar typhimurium from human and animal sources in italy. | salmonella typhimurium strains isolated in italy in the period 2002-2004 from human and animal sources were examined for their antimicrobial susceptibility. resistance to tetracycline (t, 73.6%), sulfonamides (su, 73.3%), ampicillin (a, 67.6%), streptomycin (s, 65.4%) and chloramphenicol (c, 32.3%) were frequently observed. resistance to ciprofloxacin was only observed in a swine strain, but most human strains resistant to nalidixic acid showed reduced susceptibility to that drug (mic > or = 0.1 ... | 2008 | 18054179 |
| identification of novel plasmid-mediated extended-spectrum beta-lactamase ctx-m-57 in salmonella enterica serovar typhimurium. | | 2008 | 18054206 |
| donor-strand exchange in chaperone-assisted pilus assembly revealed in atomic detail by molecular dynamics. | adhesive multi-subunit fibres are assembled on the surface of many pathogenic bacteria via the chaperone-usher pathway. in the periplasm, a chaperone donates a beta-strand to a pilus subunit to complement its incomplete immunoglobulin-like fold. at the outer membrane, this is replaced with a beta-strand formed from the n-terminal extension (nte) of an incoming pilus subunit by a donor-strand exchange (dse) mechanism. this reaction has previously been shown to proceed via a concerted mechanism, i ... | 2008 | 18054959 |
| regulation of the yjjq-bglj operon, encoding luxr-type transcription factors, and the divergent yjjp gene by h-ns and leuo. | the yjjq and bglj genes encode luxr-type transcription factors conserved in several enterobacterial species. yjjq is a potential virulence factor in avian pathogenic escherichia coli. bglj counteracts the silencing of the bgl (beta-glucoside) operon by h-ns in e. coli k-12. here we show that yjjq and bglj form an operon carried by e. coli k-12, whose expression is repressed by the histone-like nucleoid structuring (h-ns) protein. the lysr-type transcription factor leuo counteracts this repressio ... | 2008 | 18055596 |
| changes of multi-drug resistance pattern in salmonella enterica subspecies enterica serovar typhimurium isolates from food-producing animals in japan. | a total of 153 isolates of salmonella typhimurium derived from food-producing animals in japan between 2002 and 2005 were investigated for antimicrobial resistance and phage types related to definitive phage type 104 (dt104). the predominant resistance type was resistance to ampicillin, dihydrostreptomycin, kanamycin, and oxytetracycline in bovine (45.2%, 48/104) and resistance to dihydrostreptomycin and oxytetracycline in porcine isolates (58.7%, 27/48). dt104-related phage type was found in 32 ... | 2007 | 18057843 |
| structure of phage p22 cell envelope-penetrating needle. | bacteriophage p22 infects salmonella enterica by injecting its genetic material through the cell envelope. during infection, a specialized tail needle, gp26, is injected into the host, likely piercing a hole in the host cell envelope. the 2.1-a crystal structure of gp26 reveals a 240-a elongated protein fiber formed by two trimeric coiled-coil domains interrupted by a triple beta-helix. the n terminus of gp26 plugs the portal protein channel, retaining the genetic material inside the virion. the ... | 2007 | 18059287 |
| growth and genetic responses of salmonella typhimurium to ph-shifts in an anaerobic continuous culture. | salmonella infection of chickens that leads to potential human foodborne salmonellosis continues to be a concern. changes in the ph of poultry gastrointestinal tract could influence salmonella growth and virulence response. in the current study, growth responses of a chicken isolate salmonella enterica serovar typhimurium (st) to three incremental ph-shifts (6.17-7.35) in continuous cultures (cc) were evaluated. the expression of rpos and hila was determined by real time-polymerase chain reactio ... | 2008 | 18061487 |
| requirement of fur for the full induction of dps expression in salmonella enterica serovar typhimurium. | the dps protein, which is overexpressed in harsh environments, is known to play a critical role in the protection of dna against oxidative stresses. in this study, the roles of fur in the expression of the dps gene in salmonella and the protection mechanisms against oxidative stress in salmonella cells preexposed to iron-stress were investigated. two putative fur boxes were predicted within the promoter region o f th e s. typhimurium dps gene . the profile of dps expression performed by the lacz ... | 2007 | 18062222 |
| extended spectrum beta-lactamase shv-12-producing salmonella from poultry. | salmonella strains isolated from poultry and poultry products over the period 2005-2006 have been investigated in order to ascertain the presence of extended spectrum cephalosporins (esc) resistance. twelve (esc)-resistant isolates (n=1 s. enteritidis, n=1 s. braenderup and n=10 s. livingstone) were characterized as shv-12-positive. the multi-drug resistant s. livingstone shv-12-producing isolates, untypeable by pulsed-field gel electrophoresis (pfge), showed a clonal relationship by random ampl ... | 2008 | 18063489 |
| manipulation of rab gtpase function by intracellular bacterial pathogens. | intracellular bacterial pathogens have evolved highly specialized mechanisms to enter and survive within their eukaryotic hosts. in order to do this, bacterial pathogens need to avoid host cell degradation and obtain nutrients and biosynthetic precursors, as well as evade detection by the host immune system. to create an intracellular niche that is favorable for replication, some intracellular pathogens inhibit the maturation of the phagosome or exit the endocytic pathway by modifying the identi ... | 2007 | 18063721 |
| reactive oxygen species are the major antibacterials against salmonella typhimurium purine auxotrophs in the phagosome of raw 264.7 cells. | intramacrophage survival appears to be a pathogenic trait common to salmonellae and definition of the metabolic requirements of salmonella within macrophages might provide opportunities for novel therapeutic interventions. we show that loss of purg function in salmonella enterica serovar typhimurium sl1344 leads to death of the bacterium in raw264.7 cells, which was due to unavailability of purine nucleotides but not thiamine in the phagosome of raw264.7 cells. phagosomal escape of purg mutant r ... | 2008 | 18067606 |
| translating innate response into long-lasting antibody response by the intrinsic antigen-adjuvant properties of papaya mosaic virus. | identifying the properties of a molecule involved in the efficient activation of the innate and adaptive immune responses that lead to long-lasting immunity is crucial for vaccine and adjuvant development. here we show that the papaya mosaic virus (papmv) is recognized by the immune system as a pathogen-associated molecular pattern (pamp) and as an antigen in mice (pamptigen). a single immunization of papmv without added adjuvant efficiently induced both cellular and specific long-lasting antibo ... | 2008 | 18070030 |
| survival and growth of salmonella enteritidis pt 30 in almond orchard soils. | to evaluate factors potentially contributing to the long-term persistence of salmonella enterica serovar enteritidis phage type (pt) 30 in an almond orchard. | 2008 | 18070039 |
| broad-spectrum in vitro antibacterial activities of clay minerals against antibiotic-susceptible and antibiotic-resistant bacterial pathogens. | the capacity to properly address the worldwide incidence of infectious diseases lies in the ability to detect, prevent and effectively treat these infections. therefore, identifying and analysing inhibitory agents are worthwhile endeavours in an era when few new classes of effective antimicrobials have been developed. the use of geological nanomaterials to heal skin infections has been evident since the earliest recorded history, and specific clay minerals may prove valuable in the treatment of ... | 2008 | 18070832 |
| characterization of antarctic psychrotrophic bacteria with antibacterial activities against terrestrial microorganisms. | five-hundreds and eighty bacterial strains, isolated from various antarctic marine sources and locations, were screened for antimicrobial activity against terrestrial microorganisms. twenty-two antarctic isolates (3.8%), mainly retrieved from the water column at terra nova bay (ross sea), expressed antagonistic activity against one to three indicator organisms. escherichia coli and proteus mirabilis resulted as the more susceptible, followed by micrococcus luteus and bacillus subtilis. none of t ... | 2007 | 18072250 |
| foodborne zoonoses due to meat: a quantitative approach for a comparative risk assessment applied to pig slaughtering in europe. | foodborne zoonoses have a major health impact in industrialised countries. new european food safety regulations were issued to apply risk analysis to the food chain. the severity of foodborne zoonoses and the exposure of humans to biological hazards transmitted by food must be assessed. for meat, inspection at the slaughterhouse is historically the main means of control to protect consumers. however, the levels of detection of biological hazards during meat inspection have not been established i ... | 2008 | 18073088 |
| prevalence and characterization of multidrug-resistant (type acssut) salmonella enterica serovar typhimurium strains in isolates from four gosling farms and a hatchery farm. | salmonella enterica serovar typhimurium strains of phage types dt104 and u302 are often resistant to ampicillin, chloramphenicol, streptomycin, sulfonamides, and tetracycline (the acssut resistance type) and are major zoonotic pathogens. increased consumption of goose meat may enhance the risk of transferring s. enterica serovar typhimurium and other enteric pathogens from geese to human due to the consumption of meats from infected geese or improper preparation of meats. therefore, we character ... | 2008 | 18077649 |
| structure of the receptor-binding protein of bacteriophage det7: a podoviral tail spike in a myovirus. | a new salmonella enterica phage, det7, was isolated from sewage and shown by electron microscopy to belong to the myoviridae morphogroup of bacteriophages. det7 contains a 75-kda protein with 50% overall sequence identity to the tail spike endorhamnosidase of podovirus p22. adsorption of myoviruses to their bacterial hosts is normally mediated by long and short tail fibers attached to a contractile tail, whereas podoviruses do not contain fibers but attach to host cells through stubby tail spike ... | 2008 | 18077713 |
| pseudo-b12 joins the cofactor family. | | 2008 | 18083805 |
| phenotypic and proteomic characterization of multiply antibiotic-resistant variants of salmonella enterica serovar typhimurium selected following exposure to disinfectants. | in previous work, salmonella enterica serovar typhimurium strain sl1344 was exposed to sublethal concentrations of three widely used farm disinfectants in daily serial passages for 7 days in an attempt to investigate possible links between the use of disinfectants and antimicrobial resistance. stable variants oxcr1, qacfgr2, and topr2 were obtained following treatment with an oxidizing compound blend, a quaternary ammonium disinfectant containing formaldehyde and glutaraldehyde, and a tar acid-b ... | 2008 | 18083849 |
| cancer immunotherapy based on recombinant salmonella enterica serovar typhimurium aroa strains secreting prostate-specific antigen and cholera toxin subunit b. | prostate cancer is the most common malignant tumor in men and is normally associated with increased serum levels of prostate-specific antigen (psa). therefore, psa is one potential target for a prostate cancer vaccine. in this study we analyzed the functionality of new bacterial psa vaccines, expressed and secreted via the hemolysin (hlya) secretion system of escherichia coli, the prototype of type i secretion systems (t1ss) using an attenuated salmonella enterica serovar typhimurium aroa strain ... | 2008 | 18084243 |
| structural basis for the catalytic mechanism of phosphothreonine lyase. | salmonella spvc belongs to a new enzyme family designated phosphothreonine lyases that irreversibly inactivate mitogen-activated protein kinases. the crystal structure of spvc reported here reveals that the two phosphorylated residues in the substrate peptide predominantly mediate its recognition by spvc. substrate-induced conformational changes in spvc sequester the phosphothreonine in a completely solvent-free environment, preventing the hydrolysis of the phosphate group and facilitating the e ... | 2008 | 18084305 |
| hemophagocytic macrophages harbor salmonella enterica during persistent infection. | salmonella enterica subspecies can establish persistent, systemic infections in mammals, including human typhoid fever. persistent s. enterica disease is characterized by an initial acute infection that develops into an asymptomatic chronic infection. during both the acute and persistent stages, the bacteria generally reside within professional phagocytes, usually macrophages. it is unclear how salmonellae can survive within macrophages, cells that evolved, in part, to destroy pathogens. evidenc ... | 2007 | 18085823 |